US3730433A - Improvements in and relating to the coating of articles - Google Patents

Improvements in and relating to the coating of articles Download PDF

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US3730433A
US3730433A US00153019A US3730433DA US3730433A US 3730433 A US3730433 A US 3730433A US 00153019 A US00153019 A US 00153019A US 3730433D A US3730433D A US 3730433DA US 3730433 A US3730433 A US 3730433A
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reciprocator
fluidic
output
coating device
movement
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US00153019A
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J Scharfenberger
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Ransburg Corp
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Ransburg Corp
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05BSPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B13/00Machines or plants for applying liquids or other fluent materials to surfaces of objects or other work by spraying, not covered by groups B05B1/00 - B05B11/00
    • B05B13/02Means for supporting work; Arrangement or mounting of spray heads; Adaptation or arrangement of means for feeding work
    • B05B13/04Means for supporting work; Arrangement or mounting of spray heads; Adaptation or arrangement of means for feeding work the spray heads being moved during spraying operation
    • B05B13/0463Installation or apparatus for applying liquid or other fluent material to moving work of indefinite length
    • B05B13/0468Installation or apparatus for applying liquid or other fluent material to moving work of indefinite length with reciprocating or oscillating spray heads
    • B05B13/0473Installation or apparatus for applying liquid or other fluent material to moving work of indefinite length with reciprocating or oscillating spray heads with spray heads reciprocating along a straight line
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05BSPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B5/00Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
    • B05B5/08Plant for applying liquids or other fluent materials to objects
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05BSPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B13/00Machines or plants for applying liquids or other fluent materials to surfaces of objects or other work by spraying, not covered by groups B05B1/00 - B05B11/00
    • B05B13/02Means for supporting work; Arrangement or mounting of spray heads; Adaptation or arrangement of means for feeding work
    • B05B13/04Means for supporting work; Arrangement or mounting of spray heads; Adaptation or arrangement of means for feeding work the spray heads being moved during spraying operation
    • B05B13/0447Installation or apparatus for applying liquid or other fluent material to conveyed separate articles

Definitions

  • the present invention relates to an apparatus for and a method of controlling the spray emission time and the direction of movement of a spray emitting device. More particularly, the invention relates to an electrostatic spray coating system including an apparatus for and a method of controlling the spray emission time and the direction of movement of the spray emitting device.
  • Electrostatic charging and deposition of coating materials has become an accepted method by which articles of manufacture are coated in several industries. Electrostatic spray coating of articles with a coating material lowersvthe cost of finishing the articles by, among other things, reducing the amount of overspray of the coating material. In addition, electrostatic spraying of an article with a coating material tends to result in a substantially uniform deposit of the coating material upon the surface or surfaces of the article thereby providing the article with an improved finish. Furthermore, the method of electrostatically charging and depositing of coating materials is particularly advantageous in coating articles having irregular contours since, generally, employment of extraordinary procedures are not necessary to ensure a deposit of the coating material in the area of the irregular contour.
  • a device for electrostatically charging and depositing liquid coating materials such as paint, non-liquid coating materials such as powder and the like upon an article generally includes a high voltage, low current DC (direct current) power supply and a means for dispensing and charging the coating material.
  • the device may cause electrostatic atomization in the case of liquid coating materials, charging and depositing of liquid and non-liquid coating materials upon the article or the device may cause charging and depositing of the liquid and non-liquid particles of coating material upon the article.
  • a liquid coating material may be suitably atomized by electrical means, by mechanical means such as centrifugal force, hydraulic pressure, air pressure, combinations thereof and the like.
  • suitable suspension means such as a hook-shaped member may be used to suspend the article from a conveyor.
  • the conveyor is used to transport the article past the electrostatic spray device during application of the coating material thereto.
  • the hook-shaped member is usually connected to ground through the conveyor.
  • the particles of coating material dispensed by the electrostatic spray device carry an electrical charge of such a character that particles of the coating material are drawn toward and deposited upon the article carried by the hook-shaped member.
  • the article is maintained at a spray attracting potential, usually ground potential, by its connection to the hook-shaped member. Maintaining the article at about ground potential during deposition of the charged particles discharges substantially all of the charge carried by the deposited particles of coating material.
  • the effective coverage area of the spray emitted by the electrostatic spray device may be increased by repetitive or reciprocatory movement of the spray device in a direction transverse to the path of movement of the article.
  • a reciprocator having an adjustable stroke length reduces production time loss by eliminating the possiblity of having a reciprocating stroke length of 6 feet to coat a 3 foot article when a reciprocatory stroke length of about 4 feet will do nicely.
  • a problem generally associated with a reciprocating spray emitting device is that the reciprocator is unable to substantially immediately reverse its direction of movement during either its upstroke or its downstroke without experiencing a potentially harmful stress and strain of its components.
  • the speed of the reciprocator is gradually slowed to' a stop position, the direction of movement of the reciprocator is reversed and then the speed thereof is increased.
  • the variable speed of the movement of the reciprocator at about its stroke limits at a substantially constant delivery rate of coating material to the spray 1 emitting device affects the amount of coating material deposited on the article.
  • the coating material deposited upon the top and bottom edge areas tends to be excessive.
  • the excessive coating material deposited at the top and bottom edges may run or sag thereby providing an undesirable finish.
  • the reciprocator is programmed in such a manner as to cause the spray emitting device to travel past the upper and lower edges of the article during slow down and reversal of the direction of move ment of the reciprocator in an attempt to minimize excessively coating the edge areas of the article, some coating material is sprayed past the edges of the article, which results in overspray, and hence, may result in a waste of coating material.
  • liquid coating material which includes an aliphatic petroleum naptha solvent such as hexane and which is about 1.25 volume percent hexane in air at about one atmosphere of pressure requires about 0.25 millijoules of energy to be ignited. It should be recognized that the amount of energy required to ignite solvents, particulate coating material and the like may vary with, among other things, the type of solvent, the type of coating material and the like used during the application of the coating material to the article. Accordingly, it is a desideratum to provide a control system for the reciprocating spray emitting device which includes a minimum number of electrical components.
  • the invention provides an apparatus and a method which controls the emission time and the direction of movement of a spray emitting.
  • the invention provides a remote spray control apparatus which is adapted to resolve intricate spray triggering logic functions utilizing coinponents having relatively few moving parts, fast response time, low power consumption and the like. Adjustment of the spray emission time is accurately controlled since the apparatus receives signals from the reciprocator carrying the spray emitting means and, therefore, monitors the actual reversing points of the spray emitting means.
  • the present invention may also be used to control the emission time and the direction of movement of a spray emitting means of a non-electrostatic spray coating system. Further, it is contemplated that the present invention may be used with both liquid and non-liquid coating systems.
  • FIG. 1 is a view of an apparatus, with sections cutaway, which controls the emission time and the direction of movement of a spray emitting means or device;
  • FIG. 2 is a partial schematic view of the present invention
  • FIG. 3 is a cross sectional view of an H-shaped block
  • FIG. 4 is a front view of the present invention.
  • an apparatus for controlling the spray emission time and the direction of movement of a spray emitting means or spraying device is indictated by the reference numeral 10.
  • the spraying device is indicated by reference numeral 11 and the hydraulic reciprocator for the spraying device is indicated by reference numeral 12.
  • the apparatus includes a switch 13, a first fluidic trigger means 14 and a second fluidic trigger means 15 all carried by a suitable support means comprising spaced apart plates 16 and 17.
  • the switch 13 and the first fluidic trigger means 14 cooperate to control the length of time spray emission occurs from the spraying device 11.
  • the second fluidic trigger means 15 controls the direction of movement of the reciprocator 12.
  • the switch 13 includes an arcuately displaceable vane 18 and a generally U-shaped block 19 having a plurality of input ducts 20 and 21 and output ducts 22 and 23 provided therein.
  • the input duct 20 is aligned with output duct 22 so that a fluid flow from a suitable fluid source (not shown) may flow to output duct 22 through a suitable conduit (not shown) connected to the fluid source and the input duct 20.
  • the input duct 21 is similarly aligned with output duct 23.
  • the input duct 21 is connected to the fluid source (not shown) by a fluid conduit (not shown).
  • the vane 18 is arcuately displaceable within recess 26 of the U-shaped block 19 so as to be in an interference path with the fluid flow from the fluid source to either output ducts 22 or 23; that is, the vane substantially prevents fluid flow from the fluid source to either output duct 22 or duct 23.
  • the vane does not possess sufficient breadth to simultaneously prevent fluid flow to both output duct 22 and duct 23.
  • a suitable low friction slip clutch 24 is carried by the rear plate 17 of the apparatus 10.
  • the friction clutch 24 is coupled to and driven by rotatable shaft 27.
  • Shaft 27 has one extremity thereof fixedly connected to a suitable driven means such as gear 60 as shown in FIG. 2.
  • the opposite extremity of the shaft 27 is used to drive the slip clutch 24.
  • the output of the slip clutch 24 is suitably connected to vane 18 so as to arcuately displace the vane. Displacement of shaft 27 causes a displacement of vane 18 through clutch 24.
  • the slip clutch 24 is fabricated from materials having the proper characteristics for absorbing frictional energy during slippage and for dissipating heat developed during slippage.
  • the driven means, gear 60, connected to shaft 27 is rotatably driven by reciprocator 12 which displaces the spray emitting device 11.
  • Rotational displacement of shaft 27 in the clockwise direction by suitable movement of the reciprocator 12 causes a clockwise arcuate displacement of vane 18.
  • Vane 18 is displaced in a clockwise direction by the reciprocator 12 acting through the driven means, shaft 27 and the slip clutch 24.
  • stop 29, carried in recess 26 of the U-shaped block 19 displacement of the vane in the clockwise direction ceases; however, shaft 27 continues to be displaced in the clockwise direction as long as its associated driven means is rotatably displaced in the clockwise direction by movement of the reciprocator 12.
  • the clutch slips that is, shaft 27 continues to be displaced in the clockwise direction while vane 18 is retained in a stationary position due to its engagement with stop 29.
  • vane 18 is in an interference path with the fluid flow from input duct 20 to its cooperatively associated output duct 22, that is, a fluid flow is prevented between input duct 20 and output duct 22 from the fluid source.
  • a fluid flow from the fluid source through the input duct 21 to the output duct 23 occurs since said flow is not impeded by the vane 18.
  • Vane 18 Displacement of shaft 27 in the counterclockwise direction results when the reciprocator 12 reverses its direction of movement.
  • Vane 18 is displaced in a counterclockwise direction by shaft 27 acting through the slip clutch 24.
  • a suitable stop (not shown) carried in recess 26 in substantially the same manner as is stop 29, further displacement of the vane ceases.
  • the clutch 24 slips as the shaft 27 continues to be displaced in the counterclockwise direction.
  • the vane 18, while engaged with stop (not shown) effectively prevents fluid flow from input duct 21 to its cooperatively associated output duct 23. However, a fluid flow from the input duct to the output duct 22 flows since the vane 18 is no longer in a position to prevent such a fluid flow.
  • the switch 13 which includes vane 18 and the U-shaped block 19 having its input and output ducts, is responsive to a change in direction of the reciprocator to thereby terminate a fluid flow from the fluid source (not shown) to one of but not both of the output ducts; that is, a fluid flow from the fluid source always appears at one or another of the output ducts.
  • the first triggering means14 includes a plurality of substantially H-shaped fluid blocks 31, 32, 33 and 34 spaced about aperture 35 in front plate 16 and about disc 36.
  • the l-l-shaped fluid blocks 31, 32, 33 and 34 each include input and output ducts which fall within the plane of aperture 37 upon alignment of the aperture with a pair of ducts.
  • the fluid input duct to each of the fluid blocks 31 and 34 is connected to the output duct 22 of the U-shaped block 19 by a suitable fluid conduit.
  • the input ducts of fluid blocks 32 and 33 are connected to the output duct 23 of U-shaped block 19 by any suitable fluid conduit. It is seen that any fluid flow from the fluid source present at the output duct 22 or 23 of the U-shaped block 19 is caused to flow to the input ducts of H-shaped fluid blocks 32 and 33 or 31 and 34 respectively.
  • Each of the H-shaped blocks 31, 32, 33 and 34 are attached to the front plate 16 of the support means by any suitable releasable fastening means such as a bolt 61, as shown in FIG. 3, which engages with the front plate 16.
  • the fastening means may be released and the block adjustably displaced to any desired position about the periphery of aperture 35 formed in the front plate 16.
  • the first triggering means 14 also includes a displaceable or movable apertured member 36.
  • the apertured member 36 may be an apertured disc generally positioned within the aperture 35 formed in the front plate 16.
  • the member 36 includes a plurality of apertures 37 and 38 formed therein.
  • Member 36 is supported by rotatable shaft 39 suitablyjournaled in rear plate 17.
  • a suitable drive means such as a gear 62, as shown in FIG. 2, is fixedly connected to an extremity of the shaft 39 opposite to the extremity to which member 36 is attached.
  • Member 36 is driven by the gear 62 through shaft 39.
  • the gear 62, connected to shaft 39 is driven by gear 60, connected to shaft 27, through any suitable coupling or linking means such as chain 63.
  • An idler sprocket 64 rotatably journaled in rear plate 17, may be used to provide the chain 63 with the proper tension.
  • gear 60 would be smaller in diameter than gear 62.
  • the gear reduction is selected based on, for example, the desired maximum reciprocator stroke length.
  • aperture 37 is aligned with one of the ducts in H-shaped blocks 31, 32, 33 or 34 thereby allowing fluid flow from the fluid source (not shown) to flow from the input duct of that H-shaped block to the output duct of that H- shaped block.
  • the aperture 37 of the member 36 is of such length that it can be aligned with the input and output ducts of only one of the H-shaped blocks. The member 36, therefore, prevents any fluid flow to the remaining l-l-shaped blades from the fluid source from flowing to the output duct of those H-shaped blocks.
  • the position of the H-shaped blocks 31, 32, 33 and 34 along the periphery of the member 36 corresponds to the point during reciprocation of the spray device 1 1 at which it is desired to cause the device to receive a fluidic signal which causes the device to either emit or terminate emission of coating material as the case may be.
  • a fluid flow at the output duct of either l-I-shaped block 31 or 33 transmitted to the device 11 would cause the device to emit coating material.
  • a fluid flow at the output duct of either H- shaped block 32 or 34 transmitted to the device 11 would cause the device to terminate emission of a coatirig material.
  • Fluidic OR gate 44 is connected to the output ducts of the H-shaped blocks 32 and 34 through a suitable conduit.
  • the output ducts of the l-l-shaped blocks 31 and 33 are connectedto fluidic OR gate 45 through a suitable conduit.
  • the fluid OR gates 44 and 45 function to provide an output signal as long as a fluid signal appears at the input thereto.
  • Fucidic flip-flop 46 is any suitable lock-on or memory type fluidic device.
  • the flip-flop 46 has one input duct connected to the output duct of fluidic OR gate 44 and the other input duct connected to the output duct of fluidic OR gate 45 through suitable fluid conduits.
  • fluidic flip-flop 46 The operation of fluidic flip-flop 46 is similar to that well known in the fluidic art; therefore, the operation of a fluidic flp-flop will not be discussed here since the invention is not thought to reside in the flip-flop, per se.
  • the power stream (not shown) fed to the flip-flop can be switched to the desired output duct of the flip-flop and thereby used to appropriately signal the spray device 1 l suitably connected to the output duct of flip-flop 46.
  • the power stream provided to the flip-flop 46 remains locked-on the desired output until an opposite control pulse is introduced thereto of sufficient magnitude to cause the power stream to switch to the remaining output duct thereby appropriately signaling thespray device 11.
  • the flip-flop 46 is, therefore, a memory device.
  • the output of the flip-flop 46 may be amplified by any suitable fluidic amplifier (not shown) and transmitted to spray device 1 1.
  • an output flowing from one output duct of the flip-flop 46 is used to cause the spray device 11 to be actuated whereas an output flowing from the other output duct is used to cause the spray device to be deactuated.
  • a fluid flow present at the output ducts of H-shaped blocks 31 or 33 could cause the flip-flop 46 to assume such a state that the spray emission device 11 is signaled to initiate spraying whereas a fluid flow at the output ducts of H-shaped blocks 32 or 34 could cause flip-flop 46 to assume such a state that the spray emission device is signaled to terminate spraying.
  • the H-shaped blocks are so spaced about the periphery of the member 36 as to correspond to the points at which the spray emission device is to initiate or terminate spraying as the case may be. It should be noted that the H-shaped blocks 31, 32, 33 and 34 may be moved about the periphery of member 36 so as to correspond to the points during reciprocation when spraying is to be initiated or terminated.
  • the first trigger means 14 includes a plurality of fluid output ducts and input ducts which are connected to the output ducts of switch 13.
  • the switch 13 and the first trigger means 14 are used to control the length of time spray emission occurs from the spraying device 11.
  • Second trigger means 15 includes a plurality of substantially H-shaped fluid blocks 48 and 49 spaced about the periphery of member 36.
  • the H-shaped fluid blocks 48 and 49 each include input and output ducts which fall within the plane of aperture 38 when aperture 38 is aligned therewith.
  • the fluid input to the blocks 48 and 49 is supplied by a suitable fluid source (not shown) through any suitable conduit (not shown). It is seen that a fluid flow is present at the input orifices of l-l-shaped blocks 48 and 49 under all operating conditions of the apparatus 10.
  • the H-shaped blocks 48 and 49 are releasably attached to the front plate 16 by any suitable fastening means such as a bolt 61 which engages with the front plate 16.
  • the fastening means may be released and the block displaced to any desired position about the periphery of aperture 35 formed in front plate 16.
  • the H-shaped blocks 48 and 49 are spaced from each other in such a manner as to correspond to the maximum desired limits of the upstroke and downstroke of the reciprocator 12.
  • the arcuate distance separating the blocks 48 and 49 corresponds to a desired stroke distance of the reciprocator 12.
  • the arcuate distance represents a reciprocator distance reduced by a factor determined by the relationship between the circumferences ofthe gears used to drive shaft.
  • the second trigger means 15 also includes the displaceable or movable apertured member 36.
  • Aperture 38, formed in the member 36, is shown as being displaced about 180 from aperture 37. Alignment of aperture 38 of member 36 with the input and output ducts of either blocks 48 and 49 permits fluid to flow from the fluid source through the input duct to the output duct of that block, when the aperture 38 is aligned with the input and output ducts of that block. Assuming that the position of block 48 corresponds to the maximum desired upstroke distance which the reciprocator 12 travels, the alignment of the aperture 38 with the input duct and the output duct of block 48 causes a fluid flow to be transmitted to memory or lock-on flip-flop 50.
  • Flip-flop 50 is similar in construction and function to flip-flop 46.
  • the output of the flip-flop 50 may be amplified by any suitable fluidic amplifier (not shown) and transmitted to the reciprocator 12 through a suitable conduit.
  • the signal emitted by the flip-flop 50 initiated by receipt of a signal from block 48 causes the reciprocator l2'to commence its downstroke.
  • the l-l-shaped block 49 carried by the front plate 16 is used to apply an appropriate signal to the reciprocator 12 through the flip-flop 50 to cause the reciprocator to terminate its downstroke and commence its upstroke.
  • the physical posi-' tion of blocks 48 and 49 are of inverted polarity to each of their respective functions in order to provide appropriate polarization of the functions of blocks 31, 32, 33 and 34. It is seen that the length of the reciprocator stroke may be altered by displacing the H-shaped blocks 48 and 49 about the arcuate line of travel of aperture 38 without having to terminate the coating operation to effect such an alteration.
  • the H-shaped blocks 31, 32, 33 and 34 are appropriately placed about the periphery of aperture 35 so as to signal the spray device 11 to either emit or terminate emission of coating material depending on the position of the spray device with respect to the article thereby accurately controlling the amount of coating material deposited on the top and bottom edges of article 54.
  • the apparatus 10 in the manner described permits excellent control of lead and lag of the fluidic signals provided to the spray device 11.
  • the use of the low friction clutch provides the apparatus with long mechanical life.
  • the vane 18, the U-shaped block 19, and the l-l-shaped blocks 31, 32, 33 and 34 cooperate with the apertured member 36 to provide an efficient means of maintaining control of a reciprocating spray device and of spray triggering.
  • the apparatus 10 is fabricated from lightweight materials and has few moving parts. The apparatus 10 requires low mechanical forces for operation therefore, the apparatus has extended the life and reduced mechanical failure.
  • the movement of the vane 18 is controlled by the reciprocator 12 thereby permitting rapid inversion or arming of the spray device 11. Therefore, less time is spent in recycling the spray device 11 as the reciprocator reaches its upstroke and downstroke limits. The time wasted overstroking the article is minimized and precise control of paint lead lag time is accomplished resulting in a coating material savings and increased production.
  • the spraying device 11 may be any suitable spraying device such as an electrostatic spraying device.
  • a suitable electrostatic spraying device is shown in US. Pat. No. 3,169,882.
  • a suitable high voltage direct current supply 52 is connected to the electrostatic spraying device.
  • the direct current power supply 52 is capable of supplying up to about 90,000 volts direct current t the spraying device 11.
  • the spraying device 11 may be mounted for vertical reciprocation by hydraulic reciprocator 12 along the dotted line path shown in FIG. 1.
  • a suitable conveyor 51 is provided with movable conductive hook means 53 for carrying and transporting a plurality of articles 54 to be coated.
  • the conveyor 51 and the hook means 53 are electrically grounded. It is seen that the articles 54 are grounded by virtue of being connected to ground through hook means 53 and conveyor 51.
  • An apparatus for controlling the spray emission time of a spray device and the direction of movement of a reciprocator moving the spray device comprising means for controlling the spray emission time of the spray device including a fluidic switch adapted to be actuated by a change in the direction of movement of the reciprocator and a first fluidic trigger means having an input coupledto the switch and an output coupled to the spray device, the first trigger means providing a fluidic output signal to the spray device in response to actuation of the switch which triggers the spray device to an actuated or de-actuated state thereby controlling the length of time spray emission occurs from the spray device; and means for controlling the direction of movement of the reciprocator including a second fluidic trigger means responsive to and controlling the distance traveled by the reciprocator, the second trigger means providing a fluidic output signal to the reciprocator upon the reciprocator traveling a determined distance, the output signal of the second trigger means transmitted to the reciprocator causing the reciprocator to reverse its direction of movement.
  • the switch includes at least two fluid input ducts and at least two fluid output ducts and a vane interposed between the input ducts and the output ducts, the vane adapted to be responsive to a change in direction of movement of the reciprocator thereby terminating fluid flow to one of the fluid output ducts and causing fluid flow to appear at the otheroutput duct.
  • the apparatus as claimed in claim 2 further including a clutch connected to the vane, the clutch displacing the vane in response to a change in the direction of movement of the reciprocator.
  • An apparatus for controlling the emission time of a coating device and the direction of movement of a reciprocator moving the coating device comprising means for controlling the emission time of the coating device including a fluidic switch adapted to be actuated by a change in the direction of movement of the reciprocator and a first fluidic trigger means having an input coupled to the switch and an output coupled to the coating device, the first trigger means providing a fluidic output signal to the coating device in response to actuation of the switch which triggers the coating device to an actuated or de-actuated state thereby controlling the length of time emission occurs from the coating device; and means for controlling .the direction of movement of the reciprocator including a second fluidic trigger means responsive to and controlling the distance traveled by the reciprocator, the second trigger means providing a fluidic output signal to the reciprocator upon the reciprocator traveling a determined distance, the output signal of the second trigger means transmitted to the reciprocator causing the reciprocator to reverse its direction of movement.
  • the first fluidic trigger means includes a displaceable member and fluid input and output ducts, the input ducts connected to the fluidic switch, the displaceable member interrupting the fluid flow from at least one of the input ducts to at least one of the output ducts in response to the position of the reciprocator, the fluid flow at the output duct controlling the length of time emission occurs from the coating means.
  • the first fluidic trigger means includes a fluidic flip-flop connected between the output of at least one of the adjustable ducts and the reciprocator.
  • the second fluidic trigger means includes a displaceable member and fluid input and output ducts, the displaceable member interrupting the fluid flow from the input duct to the output duct in response to the position of the reciprocator, fluid flow at the output duct caus: ing the reciprocator to reverse its direction of movement.
  • the second fluidic trigger means includes a fluidic flip-flop connected between the output of at least one of the adjustable ducts and the reciprocator.
  • An apparatus for controlling the emission time of a coating device and the direction of movement of means for moving the coating device comprising means for controlling the emission time of the coating device including fluidic switch means adapted to be actuated by a change in the direction of movement of the means for moving the coating device and a first fluidic trigger means having an input coupled to the switch means and an output coupled to the coating device, the first trigger means providing a fluidic output signal to the coating device in response to actuation of the switch means for triggering the coating device to an actuated or de-actuated state to control the length of time emission occurs from the coating device; and means for controlling the direction of movement of the means for moving the coating device including a second fluidic trigger means responsive to and controlling the distance traveled by the means for moving the coating device, the second trigger means providing a fluidic output signal to the means for moving the coating device upon the means for moving the coating device traveling a determined distance, the output signal of the second trigger means transmitted to the means for moving the coating device causing the means for moving the coating device to reverse its direction of

Abstract

A fluidic apparatus for and a method of controlling the spray emission time and the direction of movement of a reciprocating spray emitting device of a spray coating system.

Description

, mted States atent n 1 1 1 Scharfenberger 1 1 ay 1, 1973 [54] IMPROVEMENTS IN AND RELATING 3,592,387 7/1971 Pilottetal ..239/186 TO THE COATING 0F ARTICLES 3,621,815 11/1971 Walberg ..239/15 3,274,860 9/1966 Gauthier et a]... ....239/l86X I to J e Scharfenberger, Indlanap- 3,219,276 11/1965 Norris ..239/186 olis,Ind 2,728,238 12 1955 Paasche..... ....239/186 3,022,011 21962 H ..239186 [73] Asslgnfle: ,Electm'coatmg Corp" 3,027,095 3i1962 Pza e e he ..239l86 Ind1anapol1s, Ind. [22] Filed: June 14, 1971 Primary Examiner-Lloyd L. King Attorney- Merrill N. Johnson, Harry E. Downer and [21] Appl. No.. 153,019 David H Badger Related US. Application Data 57 ABSTRACT [63] Continuation of Ser. No. 879,440, Nov. 24, 1969,
abandone A fluidic apparatus for and a method of controlling the spray emission time and the direction of move- 52 us. 01 ..239/15 ment of a reciprocating p y emitting device of a ,[5 1] Int. Cl. ..B05b 5/00, F23d 1 l/28 p y coating y [58] Field of Search "239/186, 15 11 Claims 4 Drawing Figures [56] References Cited UNITED STATES PATENTS 3, 93,658 7/1968 on ..239/l86X PATENTEDMAY 1 1913 N VE/VTOR JA ME 5 A. SCHARFENBERGEF PATENTEUMY m 3,730,433
SHEET 2 BF 2 ,TO FLUlD o SOURCE v RECIPROCATOR 6O 64 63 2 -TO POWER STREAM T0 44 POWER STREAM 5O INVENTOR JAMES A. SCHARFENBERGER IMPROVEMENTS IN AND RELATING TO THE COATING OF ARTICLES This is a continuation of application Ser. No. 879,440, filed Nov. 24, 1969, now abandoned.
The present invention relates to an apparatus for and a method of controlling the spray emission time and the direction of movement of a spray emitting device. More particularly, the invention relates to an electrostatic spray coating system including an apparatus for and a method of controlling the spray emission time and the direction of movement of the spray emitting device.
Electrostatic charging and deposition of coating materials has become an accepted method by which articles of manufacture are coated in several industries. Electrostatic spray coating of articles with a coating material lowersvthe cost of finishing the articles by, among other things, reducing the amount of overspray of the coating material. In addition, electrostatic spraying of an article with a coating material tends to result in a substantially uniform deposit of the coating material upon the surface or surfaces of the article thereby providing the article with an improved finish. Furthermore, the method of electrostatically charging and depositing of coating materials is particularly advantageous in coating articles having irregular contours since, generally, employment of extraordinary procedures are not necessary to ensure a deposit of the coating material in the area of the irregular contour.
A device for electrostatically charging and depositing liquid coating materials such as paint, non-liquid coating materials such as powder and the like upon an article generally includes a high voltage, low current DC (direct current) power supply and a means for dispensing and charging the coating material. The device may cause electrostatic atomization in the case of liquid coating materials, charging and depositing of liquid and non-liquid coating materials upon the article or the device may cause charging and depositing of the liquid and non-liquid particles of coating material upon the article. Where a liquid coating material is used to coat an article, it may be suitably atomized by electrical means, by mechanical means such as centrifugal force, hydraulic pressure, air pressure, combinations thereof and the like.
'A suitable suspension means such as a hook-shaped member may be used to suspend the article from a conveyor. The conveyor is used to transport the article past the electrostatic spray device during application of the coating material thereto. The hook-shaped member is usually connected to ground through the conveyor.
The particles of coating material dispensed by the electrostatic spray device carry an electrical charge of such a character that particles of the coating material are drawn toward and deposited upon the article carried by the hook-shaped member. Generally, the article is maintained at a spray attracting potential, usually ground potential, by its connection to the hook-shaped member. Maintaining the article at about ground potential during deposition of the charged particles discharges substantially all of the charge carried by the deposited particles of coating material.
Where the article to be coated is of such configuration that the entire article cannot be properly coated by a stationary spray emitting device, the effective coverage area of the spray emitted by the electrostatic spray device may be increased by repetitive or reciprocatory movement of the spray device in a direction transverse to the path of movement of the article.
When using a reciprocating spray emitting device to increase the effective coverage area of the spray, it is desirable to be able to alter the length of the stroke of the reciprocator associated with the spray emitting device without having to terminate the coating operation to effect such an alteration. For example, it may be desirable to alter the length of stroke of the reciprocator from 6 feet to 4 feet and vice-versa in order to properly coat intermittent batches of 5 foot and 3 foot articles'carried by the conveyor into coating relation with the spray emitting device without interrupting the coating operation or shutting down the conveyor line. A reciprocator having an adjustable stroke length reduces production time loss by eliminating the possiblity of having a reciprocating stroke length of 6 feet to coat a 3 foot article when a reciprocatory stroke length of about 4 feet will do nicely.
A problem generally associated with a reciprocating spray emitting device is that the reciprocator is unable to substantially immediately reverse its direction of movement during either its upstroke or its downstroke without experiencing a potentially harmful stress and strain of its components. In order to reduce the stress and strain experienced by the reciprocator to a tolerable degree during reversal of its direction of movement, the speed of the reciprocator is gradually slowed to' a stop position, the direction of movement of the reciprocator is reversed and then the speed thereof is increased. The variable speed of the movement of the reciprocator at about its stroke limits at a substantially constant delivery rate of coating material to the spray 1 emitting device affects the amount of coating material deposited on the article. If the periphery of the spray is caused to travel only to the top and bottom edge areas of the article, the coating material deposited upon the top and bottom edge areas tends to be excessive. The excessive coating material deposited at the top and bottom edges may run or sag thereby providing an undesirable finish. If the reciprocator is programmed in such a manner as to cause the spray emitting device to travel past the upper and lower edges of the article during slow down and reversal of the direction of move ment of the reciprocator in an attempt to minimize excessively coating the edge areas of the article, some coating material is sprayed past the edges of the article, which results in overspray, and hence, may result in a waste of coating material.
Another aspect which should be considered when operating a paint spray emitting device is that most commercial paints include a volatile solvent which may ignite when sparking, a disruptive discharge and the like occurs in the vicinity of the solvent. For example, liquid coating material which includes an aliphatic petroleum naptha solvent such as hexane and which is about 1.25 volume percent hexane in air at about one atmosphere of pressure requires about 0.25 millijoules of energy to be ignited. It should be recognized that the amount of energy required to ignite solvents, particulate coating material and the like may vary with, among other things, the type of solvent, the type of coating material and the like used during the application of the coating material to the article. Accordingly, it is a desideratum to provide a control system for the reciprocating spray emitting device which includes a minimum number of electrical components.
Therefore, it is an object of the present invention to provide an apparatus and a method for overcoming the abovementioned problems. The invention provides an apparatus and a method which controls the emission time and the direction of movement of a spray emitting.
means of an electrostatic spray coating system to minimize waste of the coating material and provide a quality finish. Also, the invention provides a remote spray control apparatus which is adapted to resolve intricate spray triggering logic functions utilizing coinponents having relatively few moving parts, fast response time, low power consumption and the like. Adjustment of the spray emission time is accurately controlled since the apparatus receives signals from the reciprocator carrying the spray emitting means and, therefore, monitors the actual reversing points of the spray emitting means.
It is contemplated that the present invention may also be used to control the emission time and the direction of movement of a spray emitting means of a non-electrostatic spray coating system. Further, it is contemplated that the present invention may be used with both liquid and non-liquid coating systems.
With the aforementioned objects enumerated, other objects will be apparent from reading the following description and the appended claims.
In the drawing:
FIG. 1 is a view of an apparatus, with sections cutaway, which controls the emission time and the direction of movement of a spray emitting means or device;
FIG. 2 is a partial schematic view of the present invention;
FIG. 3is a cross sectional view of an H-shaped block; and
FIG. 4 is a front view of the present invention.
Referring now to the several FIGURES of the drawing and in particular to FIG. 1, an apparatus for controlling the spray emission time and the direction of movement ofa spray emitting means or spraying device is indictated by the reference numeral 10. The spraying device is indicated by reference numeral 11 and the hydraulic reciprocator for the spraying device is indicated by reference numeral 12. The apparatus includes a switch 13, a first fluidic trigger means 14 and a second fluidic trigger means 15 all carried by a suitable support means comprising spaced apart plates 16 and 17. The switch 13 and the first fluidic trigger means 14 cooperate to control the length of time spray emission occurs from the spraying device 11. The second fluidic trigger means 15 controls the direction of movement of the reciprocator 12.
The switch 13 includes an arcuately displaceable vane 18 and a generally U-shaped block 19 having a plurality of input ducts 20 and 21 and output ducts 22 and 23 provided therein. The input duct 20 is aligned with output duct 22 so that a fluid flow from a suitable fluid source (not shown) may flow to output duct 22 through a suitable conduit (not shown) connected to the fluid source and the input duct 20. The input duct 21 is similarly aligned with output duct 23. The input duct 21 is connected to the fluid source (not shown) by a fluid conduit (not shown).
The vane 18 is arcuately displaceable within recess 26 of the U-shaped block 19 so as to be in an interference path with the fluid flow from the fluid source to either output ducts 22 or 23; that is, the vane substantially prevents fluid flow from the fluid source to either output duct 22 or duct 23. However, the vane does not possess sufficient breadth to simultaneously prevent fluid flow to both output duct 22 and duct 23.
A suitable low friction slip clutch 24 is carried by the rear plate 17 of the apparatus 10. The friction clutch 24 is coupled to and driven by rotatable shaft 27. Shaft 27 has one extremity thereof fixedly connected to a suitable driven means such as gear 60 as shown in FIG. 2. The opposite extremity of the shaft 27 is used to drive the slip clutch 24. The output of the slip clutch 24 is suitably connected to vane 18 so as to arcuately displace the vane. Displacement of shaft 27 causes a displacement of vane 18 through clutch 24. The slip clutch 24 is fabricated from materials having the proper characteristics for absorbing frictional energy during slippage and for dissipating heat developed during slippage.
The driven means, gear 60, connected to shaft 27 is rotatably driven by reciprocator 12 which displaces the spray emitting device 11. Rotational displacement of shaft 27 in the clockwise direction by suitable movement of the reciprocator 12 causes a clockwise arcuate displacement of vane 18. Vane 18 is displaced in a clockwise direction by the reciprocator 12 acting through the driven means, shaft 27 and the slip clutch 24. Upon engagement of the vane 18 with stop 29, carried in recess 26 of the U-shaped block 19, displacement of the vane in the clockwise direction ceases; however, shaft 27 continues to be displaced in the clockwise direction as long as its associated driven means is rotatably displaced in the clockwise direction by movement of the reciprocator 12. The clutch slips, that is, shaft 27 continues to be displaced in the clockwise direction while vane 18 is retained in a stationary position due to its engagement with stop 29. During engagement with stop 29, vane 18 is in an interference path with the fluid flow from input duct 20 to its cooperatively associated output duct 22, that is, a fluid flow is prevented between input duct 20 and output duct 22 from the fluid source. However, a fluid flow from the fluid source through the input duct 21 to the output duct 23 occurs since said flow is not impeded by the vane 18.
Displacement of shaft 27 in the counterclockwise direction results when the reciprocator 12 reverses its direction of movement. Vane 18 is displaced in a counterclockwise direction by shaft 27 acting through the slip clutch 24. Upon engagement of the vane 18 with a suitable stop (not shown) carried in recess 26 in substantially the same manner as is stop 29, further displacement of the vane ceases. While vane 18 is restrained from further counterclockwise displacement, the clutch 24 slips as the shaft 27 continues to be displaced in the counterclockwise direction. The vane 18, while engaged with stop (not shown) effectively prevents fluid flow from input duct 21 to its cooperatively associated output duct 23. However, a fluid flow from the input duct to the output duct 22 flows since the vane 18 is no longer in a position to prevent such a fluid flow.
It is seen that the switch 13, which includes vane 18 and the U-shaped block 19 having its input and output ducts, is responsive to a change in direction of the reciprocator to thereby terminate a fluid flow from the fluid source (not shown) to one of but not both of the output ducts; that is, a fluid flow from the fluid source always appears at one or another of the output ducts.
The first triggering means14 includes a plurality of substantially H-shaped fluid blocks 31, 32, 33 and 34 spaced about aperture 35 in front plate 16 and about disc 36. The l-l-shaped fluid blocks 31, 32, 33 and 34 each include input and output ducts which fall within the plane of aperture 37 upon alignment of the aperture with a pair of ducts. The fluid input duct to each of the fluid blocks 31 and 34 is connected to the output duct 22 of the U-shaped block 19 by a suitable fluid conduit. The input ducts of fluid blocks 32 and 33 are connected to the output duct 23 of U-shaped block 19 by any suitable fluid conduit. It is seen that any fluid flow from the fluid source present at the output duct 22 or 23 of the U-shaped block 19 is caused to flow to the input ducts of H-shaped fluid blocks 32 and 33 or 31 and 34 respectively..
Each of the H-shaped blocks 31, 32, 33 and 34 are attached to the front plate 16 of the support means by any suitable releasable fastening means such as a bolt 61, as shown in FIG. 3, which engages with the front plate 16. The fastening means may be released and the block adjustably displaced to any desired position about the periphery of aperture 35 formed in the front plate 16. i v
The first triggering means 14 also includes a displaceable or movable apertured member 36. The apertured member 36 may be an apertured disc generally positioned within the aperture 35 formed in the front plate 16. The member 36 includes a plurality of apertures 37 and 38 formed therein. Member 36 is supported by rotatable shaft 39 suitablyjournaled in rear plate 17. A suitable drive means such as a gear 62, as shown in FIG. 2, is fixedly connected to an extremity of the shaft 39 opposite to the extremity to which member 36 is attached. Member 36 is driven by the gear 62 through shaft 39. The gear 62, connected to shaft 39, is driven by gear 60, connected to shaft 27, through any suitable coupling or linking means such as chain 63. It is seen that if the gear 60 carried by shaft 27 is driven in the clockwise direction by the reciprocator, the gear 62 carried by shaft 39 is also driven in the clockwise direction and vice-versa. The shaft 39 and hence the member 36 are also driven in the clockwise direction and vice-versa. Thus, it is seen that an arcuate displacement of gear carried by shaft 39 by the gear carried by shaft 27 through the chain causes an arcuate displacement of member 36.
An idler sprocket 64, rotatably journaled in rear plate 17, may be used to provide the chain 63 with the proper tension. Generally, gear 60 would be smaller in diameter than gear 62. Such a relationship provides a suitable gear reduction so that member 36 is in concert with the movement of spray emitting device 11. The gear reduction is selected based on, for example, the desired maximum reciprocator stroke length.
Upon suitable displacement of member 36, aperture 37 is aligned with one of the ducts in H-shaped blocks 31, 32, 33 or 34 thereby allowing fluid flow from the fluid source (not shown) to flow from the input duct of that H-shaped block to the output duct of that H- shaped block. The aperture 37 of the member 36 is of such length that it can be aligned with the input and output ducts of only one of the H-shaped blocks. The member 36, therefore, prevents any fluid flow to the remaining l-l-shaped blades from the fluid source from flowing to the output duct of those H-shaped blocks.
The position of the H-shaped blocks 31, 32, 33 and 34 along the periphery of the member 36 corresponds to the point during reciprocation of the spray device 1 1 at which it is desired to cause the device to receive a fluidic signal which causes the device to either emit or terminate emission of coating material as the case may be. For example, a fluid flow at the output duct of either l-I-shaped block 31 or 33 transmitted to the device 11 would cause the device to emit coating material. A fluid flow at the output duct of either H- shaped block 32 or 34 transmitted to the device 11 would cause the device to terminate emission of a coatirig material.
It is seen that in order for a fluid to flow from the fluid source to the spray device 1 1 two conditions must be satisfied. One condition which must be satisfied is .that vane 18 should be in such a position as to allow a fluid flow from the input duct to the output duct of the U-shaped block 19. Another condition which must be satisfied is that aperture 37 must be aligned with the input duct and the output duct of the appropriate 1-!- shaped block 31, 32, 33 or 34 before the fluid from the fluid source can flow to the spray device 11. If neither one of the conditions is satisfied, a fluid pulse from the fluid source is not transmitted to the spray device 1 1.
Fluidic OR gate 44 is connected to the output ducts of the H-shaped blocks 32 and 34 through a suitable conduit. The output ducts of the l-l-shaped blocks 31 and 33 are connectedto fluidic OR gate 45 through a suitable conduit. The fluid OR gates 44 and 45 function to provide an output signal as long as a fluid signal appears at the input thereto.
F luidic flip-flop 46 is any suitable lock-on or memory type fluidic device. The flip-flop 46 has one input duct connected to the output duct of fluidic OR gate 44 and the other input duct connected to the output duct of fluidic OR gate 45 through suitable fluid conduits.
The operation of fluidic flip-flop 46 is similar to that well known in the fluidic art; therefore, the operation of a fluidic flp-flop will not be discussed here since the invention is not thought to reside in the flip-flop, per se.
By the introduction of control pulses emitted by either of the OR gates 44 or 45 to the flip-flop 46, the power stream (not shown) fed to the flip-flop can be switched to the desired output duct of the flip-flop and thereby used to appropriately signal the spray device 1 l suitably connected to the output duct of flip-flop 46. The power stream provided to the flip-flop 46 remains locked-on the desired output until an opposite control pulse is introduced thereto of sufficient magnitude to cause the power stream to switch to the remaining output duct thereby appropriately signaling thespray device 11. The flip-flop 46 is, therefore, a memory device.
If desired, the output of the flip-flop 46 may be amplified by any suitable fluidic amplifier (not shown) and transmitted to spray device 1 1.
Generally, an output flowing from one output duct of the flip-flop 46 is used to cause the spray device 11 to be actuated whereas an output flowing from the other output duct is used to cause the spray device to be deactuated. For example, a fluid flow present at the output ducts of H-shaped blocks 31 or 33 could cause the flip-flop 46 to assume such a state that the spray emission device 11 is signaled to initiate spraying whereas a fluid flow at the output ducts of H-shaped blocks 32 or 34 could cause flip-flop 46 to assume such a state that the spray emission device is signaled to terminate spraying.
The H-shaped blocks are so spaced about the periphery of the member 36 as to correspond to the points at which the spray emission device is to initiate or terminate spraying as the case may be. It should be noted that the H-shaped blocks 31, 32, 33 and 34 may be moved about the periphery of member 36 so as to correspond to the points during reciprocation when spraying is to be initiated or terminated.
It is seen that the first trigger means 14 includes a plurality of fluid output ducts and input ducts which are connected to the output ducts of switch 13. The switch 13 and the first trigger means 14 are used to control the length of time spray emission occurs from the spraying device 11.
Second trigger means 15 includes a plurality of substantially H-shaped fluid blocks 48 and 49 spaced about the periphery of member 36. The H-shaped fluid blocks 48 and 49 each include input and output ducts which fall within the plane of aperture 38 when aperture 38 is aligned therewith. The fluid input to the blocks 48 and 49 is supplied by a suitable fluid source (not shown) through any suitable conduit (not shown). It is seen that a fluid flow is present at the input orifices of l-l-shaped blocks 48 and 49 under all operating conditions of the apparatus 10.
The H-shaped blocks 48 and 49 are releasably attached to the front plate 16 by any suitable fastening means such as a bolt 61 which engages with the front plate 16. The fastening means may be released and the block displaced to any desired position about the periphery of aperture 35 formed in front plate 16. The H-shaped blocks 48 and 49 are spaced from each other in such a manner as to correspond to the maximum desired limits of the upstroke and downstroke of the reciprocator 12. The arcuate distance separating the blocks 48 and 49 corresponds to a desired stroke distance of the reciprocator 12. The arcuate distance represents a reciprocator distance reduced by a factor determined by the relationship between the circumferences ofthe gears used to drive shaft.
The second trigger means 15 also includes the displaceable or movable apertured member 36. Aperture 38, formed in the member 36, is shown as being displaced about 180 from aperture 37. Alignment of aperture 38 of member 36 with the input and output ducts of either blocks 48 and 49 permits fluid to flow from the fluid source through the input duct to the output duct of that block, when the aperture 38 is aligned with the input and output ducts of that block. Assuming that the position of block 48 corresponds to the maximum desired upstroke distance which the reciprocator 12 travels, the alignment of the aperture 38 with the input duct and the output duct of block 48 causes a fluid flow to be transmitted to memory or lock-on flip-flop 50.
Flip-flop 50 is similar in construction and function to flip-flop 46. The output of the flip-flop 50 may be amplified by any suitable fluidic amplifier (not shown) and transmitted to the reciprocator 12 through a suitable conduit. The signal emitted by the flip-flop 50 initiated by receipt of a signal from block 48 causes the reciprocator l2'to commence its downstroke.
The l-l-shaped block 49 carried by the front plate 16 is used to apply an appropriate signal to the reciprocator 12 through the flip-flop 50 to cause the reciprocator to terminate its downstroke and commence its upstroke. It should be appreciated that the physical posi-' tion of blocks 48 and 49 are of inverted polarity to each of their respective functions in order to provide appropriate polarization of the functions of blocks 31, 32, 33 and 34. It is seen that the length of the reciprocator stroke may be altered by displacing the H-shaped blocks 48 and 49 about the arcuate line of travel of aperture 38 without having to terminate the coating operation to effect such an alteration.
The H-shaped blocks 31, 32, 33 and 34 are appropriately placed about the periphery of aperture 35 so as to signal the spray device 11 to either emit or terminate emission of coating material depending on the position of the spray device with respect to the article thereby accurately controlling the amount of coating material deposited on the top and bottom edges of article 54.
Using the apparatus 10 in the manner described permits excellent control of lead and lag of the fluidic signals provided to the spray device 11. The use of the low friction clutch provides the apparatus with long mechanical life. The vane 18, the U-shaped block 19, and the l-l-shaped blocks 31, 32, 33 and 34 cooperate with the apertured member 36 to provide an efficient means of maintaining control of a reciprocating spray device and of spray triggering. The apparatus 10 is fabricated from lightweight materials and has few moving parts. The apparatus 10 requires low mechanical forces for operation therefore, the apparatus has extended the life and reduced mechanical failure.
The movement of the vane 18 is controlled by the reciprocator 12 thereby permitting rapid inversion or arming of the spray device 11. Therefore, less time is spent in recycling the spray device 11 as the reciprocator reaches its upstroke and downstroke limits. The time wasted overstroking the article is minimized and precise control of paint lead lag time is accomplished resulting in a coating material savings and increased production.
The spraying device 11 may be any suitable spraying device such as an electrostatic spraying device. A suitable electrostatic spraying device is shown in US. Pat. No. 3,169,882. A suitable high voltage direct current supply 52 is connected to the electrostatic spraying device. The direct current power supply 52 is capable of supplying up to about 90,000 volts direct current t the spraying device 11.
The spraying device 11 may be mounted for vertical reciprocation by hydraulic reciprocator 12 along the dotted line path shown in FIG. 1.
A suitable conveyor 51 is provided with movable conductive hook means 53 for carrying and transporting a plurality of articles 54 to be coated. The conveyor 51 and the hook means 53 are electrically grounded. It is seen that the articles 54 are grounded by virtue of being connected to ground through hook means 53 and conveyor 51.
The present invention is not intended to be limited by the disclosure herein, changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention. Such modifications are considered to be within the purview and scope of the present invention and appended claims.
I claim:
1. An apparatus for controlling the spray emission time of a spray device and the direction of movement of a reciprocator moving the spray device, the apparatus comprising means for controlling the spray emission time of the spray device including a fluidic switch adapted to be actuated by a change in the direction of movement of the reciprocator and a first fluidic trigger means having an input coupledto the switch and an output coupled to the spray device, the first trigger means providing a fluidic output signal to the spray device in response to actuation of the switch which triggers the spray device to an actuated or de-actuated state thereby controlling the length of time spray emission occurs from the spray device; and means for controlling the direction of movement of the reciprocator including a second fluidic trigger means responsive to and controlling the distance traveled by the reciprocator, the second trigger means providing a fluidic output signal to the reciprocator upon the reciprocator traveling a determined distance, the output signal of the second trigger means transmitted to the reciprocator causing the reciprocator to reverse its direction of movement.
2. The apparatus as claimed in claim 1, wherein the switch includes at least two fluid input ducts and at least two fluid output ducts and a vane interposed between the input ducts and the output ducts, the vane adapted to be responsive to a change in direction of movement of the reciprocator thereby terminating fluid flow to one of the fluid output ducts and causing fluid flow to appear at the otheroutput duct.
3. The apparatus as claimed in claim 2 further including a clutch connected to the vane, the clutch displacing the vane in response to a change in the direction of movement of the reciprocator.
4. An apparatus for controlling the emission time of a coating device and the direction of movement of a reciprocator moving the coating device, the apparatus comprising means for controlling the emission time of the coating device including a fluidic switch adapted to be actuated by a change in the direction of movement of the reciprocator and a first fluidic trigger means having an input coupled to the switch and an output coupled to the coating device, the first trigger means providing a fluidic output signal to the coating device in response to actuation of the switch which triggers the coating device to an actuated or de-actuated state thereby controlling the length of time emission occurs from the coating device; and means for controlling .the direction of movement of the reciprocator including a second fluidic trigger means responsive to and controlling the distance traveled by the reciprocator, the second trigger means providing a fluidic output signal to the reciprocator upon the reciprocator traveling a determined distance, the output signal of the second trigger means transmitted to the reciprocator causing the reciprocator to reverse its direction of movement.
5. The apparatus as claimed in claim 4, wherein the first fluidic trigger means includes a displaceable member and fluid input and output ducts, the input ducts connected to the fluidic switch, the displaceable member interrupting the fluid flow from at least one of the input ducts to at least one of the output ducts in response to the position of the reciprocator, the fluid flow at the output duct controlling the length of time emission occurs from the coating means.
6. The apparatus as claimed in claim 5, wherein the fluid input and output ducts are adjustable with respect to the displaceable member.
7. The apparatus as claimed in claim 6, wherein the first fluidic trigger means includes a fluidic flip-flop connected between the output of at least one of the adjustable ducts and the reciprocator.
8. The apparatus as claimed in claim 5, wherein the second fluidic trigger means includes a displaceable member and fluid input and output ducts, the displaceable member interrupting the fluid flow from the input duct to the output duct in response to the position of the reciprocator, fluid flow at the output duct caus: ing the reciprocator to reverse its direction of movement.
9. The apparatus as claimed in claim 8, wherein the fluid input and output ducts are adjustable with respect to the displaceable member.
10. The apparatus as claimed in claim 9, wherein the second fluidic trigger means includes a fluidic flip-flop connected between the output of at least one of the adjustable ducts and the reciprocator.
l 1. An apparatus for controlling the emission time of a coating device and the direction of movement of means for moving the coating device, the apparatus comprising means for controlling the emission time of the coating device including fluidic switch means adapted to be actuated by a change in the direction of movement of the means for moving the coating device and a first fluidic trigger means having an input coupled to the switch means and an output coupled to the coating device, the first trigger means providing a fluidic output signal to the coating device in response to actuation of the switch means for triggering the coating device to an actuated or de-actuated state to control the length of time emission occurs from the coating device; and means for controlling the direction of movement of the means for moving the coating device including a second fluidic trigger means responsive to and controlling the distance traveled by the means for moving the coating device, the second trigger means providing a fluidic output signal to the means for moving the coating device upon the means for moving the coating device traveling a determined distance, the output signal of the second trigger means transmitted to the means for moving the coating device causing the means for moving the coating device to reverse its direction of movement.

Claims (11)

1. An apparatus for controlling the spray emission time of a spray device and the direction of movement of a reciprocator moving the spray device, the apparatus comprising means for controlling the spray emission time of the spray device including a fluidic switch adapted to be actuated by a change in the direction of movement of the reciprocator and a first fluidic trigger means having an input coupled to the switch and an output coupled to the spray device, the first trigger means providing a fluidic output signal to the spray device in response to actuation of the switch which triggers the spray device to an actuated or de-actuated state thereby controlling the length of time spray emission occurs from the spray device; and means for controlling the direction of movement of the reciprocator including a second fluidic trigger means responsive to and controlling the distance traveled by the reciprocator, the second trigger means providing a fluidic output signal to the reciprocator upon the reciprocator traveling a determined distance, the output signal of the second trigger means transmitted to the reciprocator causing the reciprocator to reverse its direction of movement.
2. The apparatus as claimed in claim 1, wherein the switch includes at least two fluid input ducts and at least two fluid output ducts and a vane interposed between the input ducts and the output ducts, the vane adapted to be responsive to a change in direction of movement of the reciprocator thereby terminating fluid flow to one of the fluid output ducts and causing fluid flow to appear at the other output duct.
3. The apparatus as claimed in claim 2 further including a clutch connected to the vane, the clutch displacing the vane in response to a change in the direction of movement of the reciprocator.
4. An apparatus for controlling the emission time of a coating device and the direction of movement of a reciprocator moving the coating device, the apparatus comprising means for controlling the emission time of the coating device including a fluidic switch adapted to be actuated by a change in the direction of movement of the reciprocator and a first fluidic trigger means having an input coupled to the switch and an output coupled to the coating device, the first trigger means providing a fluidic output signal to the coating device in response to actuation of the switch which triggers the coating device to an actuated or de-actuated state thereby controlling the length of time emission occurs from the coating device; and means for controlling the direction of movement of the reciprocator including a second fluidic trigger means responsive to and controlling the distance traveled by the reciprocator, the second trigger means providing a fluidic output signal to the reciprocator upon the reciprocator traveling a determined distance, the output signal of the second trigger means transmitted to the reciprocator causing the reciprocator to reverse its direction of movement.
5. The apparatus as claimed in claim 4, wherein the first fluidic trigger means includes a displaceable member and fluid input and output ducts, the input ducts connected to the fluidic switch, the displaceable member interrupting the fluid flow from at least one of the input ducts to at least one of the output ducts in response to the position of the reciprocator, the fluid flow at the ouTput duct controlling the length of time emission occurs from the coating means.
6. The apparatus as claimed in claim 5, wherein the fluid input and output ducts are adjustable with respect to the displaceable member.
7. The apparatus as claimed in claim 6, wherein the first fluidic trigger means includes a fluidic flip-flop connected between the output of at least one of the adjustable ducts and the reciprocator.
8. The apparatus as claimed in claim 5, wherein the second fluidic trigger means includes a displaceable member and fluid input and output ducts, the displaceable member interrupting the fluid flow from the input duct to the output duct in response to the position of the reciprocator, fluid flow at the output duct causing the reciprocator to reverse its direction of movement.
9. The apparatus as claimed in claim 8, wherein the fluid input and output ducts are adjustable with respect to the displaceable member.
10. The apparatus as claimed in claim 9, wherein the second fluidic trigger means includes a fluidic flip-flop connected between the output of at least one of the adjustable ducts and the reciprocator.
11. An apparatus for controlling the emission time of a coating device and the direction of movement of means for moving the coating device, the apparatus comprising means for controlling the emission time of the coating device including fluidic switch means adapted to be actuated by a change in the direction of movement of the means for moving the coating device and a first fluidic trigger means having an input coupled to the switch means and an output coupled to the coating device, the first trigger means providing a fluidic output signal to the coating device in response to actuation of the switch means for triggering the coating device to an actuated or de-actuated state to control the length of time emission occurs from the coating device; and means for controlling the direction of movement of the means for moving the coating device including a second fluidic trigger means responsive to and controlling the distance traveled by the means for moving the coating device, the second trigger means providing a fluidic output signal to the means for moving the coating device upon the means for moving the coating device traveling a determined distance, the output signal of the second trigger means transmitted to the means for moving the coating device causing the means for moving the coating device to reverse its direction of movement.
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US5482556A (en) * 1990-10-09 1996-01-09 Nordson Corporation Apparatus for mounting and moving coating dispensers
US20020192360A1 (en) * 2001-04-24 2002-12-19 3M Innovative Properties Company Electrostatic spray coating apparatus and method
US6579574B2 (en) * 2001-04-24 2003-06-17 3M Innovative Properties Company Variable electrostatic spray coating apparatus and method

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Publication number Priority date Publication date Assignee Title
US5482556A (en) * 1990-10-09 1996-01-09 Nordson Corporation Apparatus for mounting and moving coating dispensers
US20020192360A1 (en) * 2001-04-24 2002-12-19 3M Innovative Properties Company Electrostatic spray coating apparatus and method
US6579574B2 (en) * 2001-04-24 2003-06-17 3M Innovative Properties Company Variable electrostatic spray coating apparatus and method
US20040185180A1 (en) * 2001-04-24 2004-09-23 3M Innovative Properties Company Electrostatic spray coating apparatus and method
US6969540B2 (en) 2001-04-24 2005-11-29 3M Innovative Properties Company Electrostatic spray coating apparatus and method

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