US3359916A - Fluid control structure - Google Patents

Description

1967 J, B. HOUSTON ETAL 3,35 ,916

FLUID CONTROL STRUCTURE 2 Sheets-Sheet 2 Filed Oct. 24, 1965 71 Jan 7x04 United States Patent 3,359,916 FLUID CONTROL STRUCTURE Joe B. Houston, 2267 Roscomare Road, Los Angeles, Calif. 90024, and Harvey H. Davis, 4145 Lynd Ave., Arcadia, Calif. 91006 Filed Oct. 24, 1965, Ser. No. 504,468 Claims. (Cl. 103-152) ABSTRACT OF THE DISCLOSURE A collapsible-duct pump incorporating structure to collapse an intake section of the duct initially so that the remainder of the duct can be collapsed by air pressure to force pumpage from the outlet without backflow. Incompressible fluid about the duct reduces the required airflow and various arrangements are disclosed for cycling the pump. Pluralities of the pumps are shown both in series and parallel arrangements.

The present invention relates to a fluid control system for controlling the movement of a fluid, a slurry of relatively high viscosity, or even a somewhat solid materia It has become rather widespread practice in the building industry to place concrete by forcing it through a duct to a desired location while it is in a slurry or somewhat fluid state. This technique is particularly useful in transporting concrete to the upper floors of a multi-story building. However, difliculties in using the technique sometimes stem from the pump or other actuator employed to move the slurry. For example, prior pumps for use in this application conventionally employ drive mechanisms which develop considerable inertia. As a result, if for some reason the flow duct becomes obstructed or blocked before the drive mechanism can be stopped, it may apply intolerable pressure to the slurry. Upon such an occurrence, the duct may break propelling concrete slurry and aggregate with dangerous force.

Another aspect of prior pumps or actuator mechanisms for moving concrete slurries is their requirement for considerable capacity for developing high pressures. As a result, these structures have generally been quite expensive to manufacture, use and maintain. Furthermore, the high fluid pressures and mechanical forces of prior pumps have often prevented their use for placing lightweight concrete in which the aggregate would break down or become water impregnated under such forces. These forces sometimes also tend to impair the final quality of regular or rock-aggregate concrete.

One other aspect of prior pumps for use in moving concrete has been the abrading effect of aggregate materials on components of the pump that actually engage the concrete. That is, prior pumps have normally been subject to considerable wear resulting from direct mechanical force applied to abrasive aggregates.

In view of these considerations, a need exists for an improved pump or fluid control structure which may be employed to move, and to control the movement of high viscosity liquids as concrete, various slurries and other fluids or semi-fluids. Another specific exemplary application for a pump valve or fluid control structure which has relatively few moving parts and essentially no solid moving parts which contact the controlled fluid is for controlling the flow of corrosive fluids.

It is therefore a general object of the present invention to provide an improved fluid control structure as may be embodied for example in a valve or a pump, for overcoming the objections of various structures of the prior art as considered above.

Another object of the present invention is to provide an improved invention pump, wherein relatively few moving parts are provided, and which is useful for pumping generally diflicult substances as concrete and corrosive fluids.

Still another object of the present invention is to provide an improved concrete pump which can be relatively inexpensively manufactured and maintained, which is economical in use, and reliable in operation.

Still one other object of the present invention is to provide an improved concrete pump, the operation of which avoids impacting abrasive aggregates against wear surfaces under direct mechanical force.

A further object of the present invention is to provide an improved basic fluid control structure as may be variously embodied to move and control the movement of fluids, semi-fluids and even semi-solids; the transportation of which have in the past presented a considerable problem.

In accordance with these objects, the objective structure hereof includes a flexible or deformable duct which is adapted to be connected to a source of pumpage and which is contained within a closed housing which incorporates means for varying the fluid pressure within the space between the duct and the housing whereby to control the I movement of or actually move the pumpage.

These and other objects hereof will be apparent to one skilled in the art from a consideration of the following, in conjunction with the appended drawings, wherein:

FIGURE 1 is a perspective view of a concrete delivery structure incorporating the principles of the present invention;

FIGURE 2 is a sectional view taken along line 2-2 of FIGURE 1;

FIGURE 3 is a central horizontal section taken through FIGURE 2;

FIGURE 4 is a sectional diagrammatic view of a structure in accordance with the present invention;

FIGURE 5 is a fragmentary view similar to FIGURE 4, showing the components in another operating relationship;

FIGURE 6 is a view similar to FIGURE 5 showing the components in still another operating relationship;

FIGURE 7 is a sectional diagrammatic view of another structure in accordance with the present invention;

FIGURE 8 is a sectional diagrammatic view of still another structure in accordance with the present invention; and

FIGURE 9 is a sectional diagrammatic view of still another structure in accordance with the present invention.

Refer-ring initially to FIGURE 1, there is shown a delivery structure 10 for placing concrete in a building 12. More specifically, a tower 14 supports a hopper 16 at various heights and provides a bucket elevator for delivering concrete to the hopper. Concrete placed in the hopper 16 passes through an outlet 18 which is directly connected to a pump 20 that functions to deliver the concrete at a desired location within the building 12 through a hose 22. The pump 20 is pneumatically powered through an air line which is adapted to be connected to a source of air under pressure. In operaiton, air passing from the line 24 into the pump 20 is controlled by a cycling system- 26 as will now be considered in greater detail to further explain the structure of the system with reference to FIGURES 4, 5 and 6.

Referring initially to FIGURE 4, a bucket 30 of an elevator as shown in FIGURE 1, is illustrated in a dumping posiiton and also shown in phantom in a position immediately before the dumping position. Concrete 31 is delivered by the bucket 30 into a hopper 32, the lower end 34 of which is reduced in section and connected through a connector 35 to a rigid ingress duct or tube 36.

The lower end 34 of the hopper 32 contains a fixed blowby safety device or shield 38 in the form of a circular, concave-convex rigid structure for bleeding ofi air in the event of a component failure.

The pump intake tube 36 is sealed telescopically into a closed shell or housing 40 which may be of somewhat elongate cylindrical form and made of metal or other rigid material, capable of confining substantial pressure. An outlet tube 42 incorporating a reducing cone is sealed in the opposed end of the housing 40, also extending therein. The internal extensions 44 and 46 of the tubes 36 and 42 respectively then receive a cylindrical diaphragm, or flexible duct 48 which is rigidly fixed to extend the full length of the housing 40.

The duct 48 may comprise a rubber hose, reinforced with synthetic fabric as nylon for example, to provide adequate flexibility for collapse, and good wear characteristics with relatively little fatigue deterioration. The concentric placement of the duct 48 within the housing 40 provides a chamber 49 between these members which contains oil 50 or other incompressible fluid.

In the operation of the structure as shown in FIGURE 4, concrete 31 flows into the duct 48 from the hopper 32 and is then exhausted from the duct by its collapse under pressure to force the concrete through the exhaust tube 42 and a hose 52. To cycle the pressurization of the chamber 49, a probe head 54 senses the operating phase of the duct 48. When the duct 48 is collapsed, the chamber 49 is opened to relieve the pressure therein and allow concrete 31 to gravity flow into the duct 48. Then when the duct 48 is filled with concrete, the chamber 49 is pressurized, collapsing the duct 48 to move the concrete.

Considering the control structure in greater detail, the probe head 54 is carried on an elongate rod shaft 60 which passes in sealed relationship through the housing 40 to engage a movable contact 62 of a switch 64. The contact 62 is electrically coupled to a source of potential and mechanically connected to a compression spring 66 which is fixed so as to urge the probe head 54 into the housing 40, acting through the movable contact 62.

The movable contact 62 operates in cooperation with a fixed contact 68 that is connected to a time-delay circuit 70, which may comprise a time delay relay, the operation of which lags that of the control switch 64, as well-known in the prior art. That is the time-delay circuit 70 applies electrical control signals from the switch 64 to a solenoid valve control 72 in time delayed relationship to the signals from the switch 64.

The solenoid valve control 72 actuates a two-way valve 74 which is shown in its residual or quiescent position,

connecting an air channel 78 of the housing 40, to an exhaust outlet 80. Upon energization of the solenoid valve control 72, the valve 74 is revolved in a clockwise direction to connect the air channel 78 to an intake 82, adapted to be connected to a source of air under pressure.

Considering the operation of the system in greater detail, reference will now be made to FIGURES and 6, along with FIGURE 4. The similar components and elements in all these figures are identical by like reference numerals. Referring first to FIGURE 4, in the stage-ofoperation illustrated the duct 48 has filled with concrete 31 flowing under gravity force from the hopper 32. The probe head 54 is urged outward by the expanded or open shape of the duct 48 so that the switch 64 is closed applying a control signal to the time-delay circuit 70; however, that circuit is depicted in a state of delaying the application of the control signal to actuate the solenoid valve control 72.

At the expiration of the delay period illustrated in FIGURE 4 as explained above, the solenoid valve control actuates the valve 74 by imparting a quarter-revolution clockwise movement to the valve as shown in FIGURE 5. It is to be noted that the control structure as illustrated dashed line in FIGURES 5 and 6.

With the valve 74 actuated as shown in FIGURE 5, air under pressure enters the housing 40 through the channel 78 to pressurize the chamber 49. The pressure in the chamber 49 is applied somewhat uniformly to the flexible duct 48; however, in view of the static head of the concrete contained in the duct 48, that member collapse initially at a pinch 80, near the top of the duct. That is, as the static head along the length of the duct 48 is lowest near the top, collapse initially occurs near the top.

The pinch 80 as shown in FIGURE 5 becomes a valve to prevent back flow into the tube 36, and also forms the leading edge of the pump in action. That is, as the chamber 49 is pressurized, the duct 48 continues to collapse along its length extending the pinch 80 (FIGURE 5) to a collapse 82 (FIGURE 6) and thereby expelling concrete through the tube 42.

At the conclusion of the exhaust action, as depicted in FIGURE 6, the probe head 54 moved inward with the collapse of the duct 48, thereby allowing the contact 62 to withdraw from the contact 68. As a result, after a brief time delay incurred by the circuit 70, the solenoid valve control is de-energized, allowing the valve 74 to return the position as shown in FIGURE 4 connecting the chamber 49, to the exhaust channel 80. Therefore, the chamber 49 is relieved allowing concrete 31 to re-filled the duct 48 so the cycle can be repeated. In this manner, the system cycles and recycles, pumping concrete from the hopper 32 out through the tube 42 for placement through pipes, hoses, conduits or other passages at the desired placement location.

It is to be noted, that in the operation of the system as shown, the volume of pressurized air or other gas which is spent in a cycle of operation is limited somewhat as the actual volume of concrete that is actually displaced. That is as the oil 50 substantially fills the void of the chamber 4? when the duct 48 is loaded, the space developed in the chamber 49 is substantially limited by the volume of concrete that is displaced. Of course, this arrangement obtains a considerable improvement in operating efliciency.

It is readily apparent that the basic structure hereof may take a wide variety of different forms one rather specific design of which has been found effective and is shown in detail in FIGURES 2 and 3. In this design, the outlet 18 (FIGURE 1) from the hopper 16 is connected to a rigid intake duct (FIGURE 2) entering the pump structure. An external flange 102 is welded onto the duct 100 and is aflixed by bolts to a clamp ring 104, with the end 106 of a flexible pump sleeve 108 therebe-tween. The sleeve 108 is similar to the flexible duct as previously described and may comprise an elongate cylinder of neoprene rubber reinforced with steel mesh and nylon. In the design, the sleeve is approximately ten inches in diameter and some eight feel in length; however, it is stressed that these dimensions are, of Course, merely illustrative.

The duct 100 bearing the sleeve 108 extends into a chamber defined by a pair of elongate mating channels -112 (FIGURE 3) which are somewhat concave-convex in section. These channels are mated together to define an elongate cylindrical chamber 114 with parallel opposed elongate tapered slots 116 and 118 extending along the length thereof. structurally the two channels may be formed of steel and are held in mated relationship by four exterior braces 120 (FIGURE 2). The braces 120 comprising steel for example are Welded to the channels 112 which are in turn welded to the ring 104 (FIGURE 2) at the upper end thereof. The lower ends of the channels 112 are welded to a ring 122 which is in turn alfixed by bolts 124 to a flange 126 which is welded to an exit duct or tube 130. The tube 130 receives the lower end of the sleeve 108, molded thereon over annular ridges 132, and is connected to a hose or tubing 22 (FIGURE 1) through which concrete is delivered.

In the operation of the structure as shown in FIG;

URES 2 and 3 air is received under pressure through an intake 134 (FIGURE 2) and the state of the operating cycle is sensed by a probe structure 138 for control purposes as previously described. In view of this structural description of the design embodiment of FIGURES 1, 2, and 3, the detailed operation thereof will now be to exhaust the concrete therein out of the tube 130. Asthe sleeve 108 collapses, it assumes a configuration as,

shown by the phantom sleeve 108a (FIGURE 2). It is to be noted, that the collapsed sleeve 108, at the upper end thereof engages rings 142 and a ball 144 held spaced apart by brackets 146 that are afiixed t the duct 100 asby welding to define a somewhat conical shape for internal support. The arrangement of this structure is also shown in the upper section of FIGURE 3 taken through.

the duct 100 above the flange 102. The lower section of FIGURE 2 is taken from a central location in the pump.

The existing concrete from the sleeve 108 is moved toward the desired delivery location and when the evacuation is complete another cycle is initiated by concrete flowing to refill the sleeve 108. It is to be noted that in the operation of the system, the pressures applied to the concrete never exceed the regulated pressure of the ap-' plied air. Furthermore, the concrete is not subjected to mechanical shock forces as by pistons or the like. Still further, the flexible sleeve, gland or pump duct in the system is not mechanically driven, with the result that extended period of trouble-free operation can be expected.

In some instances, it may be desirable to operate a.

form of the structure hereof with the collapsible sleeve or duct positioned horizontally, to move pumpage having some initial head. In such an instance, additional structure may be provided to form the initial pinch at the desired location. That is, as there 'is no substantial static head differential along the length of the horizontal sleeve, structure is provided to form the pinch at the desired location as shown in FIGURE 8.

The structure shown is generally similar to that of FIG- URE 4 and like elements bear the same reference numerals. The additional elements comprise a pair of opposed pneumatic rams 150 and 152 that are connected to the pump air intake 78. The ram 150 includes a pneumatic actuator 154 for driving a pinch plunger 156. Similarly, the ram 152 includes an actuator 158 for driving a pinch plunger 160.

Operation of the embodiment of FIGURE 8 is substantially similar the embodiment of FIGURE 4. However, when the chamber 49 is pressurized through the intake 78, the actuators 154 and 158 are also pressurized to ex,- tend the opposed pinch plungers 156 and 160 respectively, whereby to form the initial collapse or pinch 162 in the duct 48. After the pinch 162 is so formed, it provides a valve to prevent back flow and the remainder of the duct 48 can be collapsed to move the concrete or other contained pumpage. Additional strength may be built into the duct 48 at the locationof the pinch 162, if desired.

The probe rod 60 senses the conclusion of the pump cycle to relieve the pressure in the chamber 49 as described above. Thereupon, the pinch plungers 156 and 160 are also released permitting pumpage to be forced into the duct 48 during the next cycle.

The embodiment of FIGURE 8, as well as other embodiments hereof can be variously incorporated in fluid control systems. For example, it may be desirable to provide many individual pumps along an extended flow path as shown in FIGURE 9. In that structure, a pair of pilot pumps control a series of interconnected pumps to drive pumpage along a considerable flow path. Of course, the displacement between the individual pumps will depend on the nature of the pumpage and the basic design considerations of the system; however, for purposes of illustration only, the pumps in FIGURE 9 are shown contiguous.

The individual pump structures of FIGURE 9 may be similar to those as described above and are designated P1, P2, P3, P4, P5, P6 and P7 in accordance with their position in the interconnected series. The pumps P1 and P2 are pilot pumps to which all the other pumps are slave operated. This is, all the odd numbered pumps operate in phase with the pump P1, while the even numbered pumps are slaved to the pump P2. Specifically, the pump P1 includes a probe structure extending from a control valve 172 which is adapted to be connected to a source of air under pressure and provides an outlet through a line channel 174 to an actuator 176 that is connected to one end of a spool valve 178. In a similar arrangement a probe structure 180 controls a valve 182 which regulates air flow through a line-indicated channel 184 to an actuator 186 that is connected to the spool valve 17 8 in opposition to the actuator 176. Various forms of well-known actuators may 'be employed as the actuators 176 and 186 which exert a force in accordance with applied pressure. One specific form of such actuator may be simply a piston operating in an orificed cylinder.

In the operation of the system of FIGURE 9, the series of pumps is connected to a source of pumpage through a duct 190. An initial priming or charging may be necessary to load the first pump P1 in the series; however, some static head sulfcient to move the pumpage through the duct 190 into the first pump P1 is assumed. Upon the pump P1 becoming filled with pumpage, the probe structure 170 opens the valve 172 thereby developing increased force by the actuator 176 urging the spool valve 178 to the left. At this time, the pump P2 is substantially empty so that the valve 182 is essentially closed with the result that the actuator 186 exerts little force urging the spool valve 178 to the right.

The differential in forces applied to the spool valve 178 by the actuators 176 and 186 causes the spool valve to move to the left connecting the ducts 190 to a pressure duct 192, through the spool valve chamber 194. With the spool valve 178 in the left position, the ducts 196' are connected to the discharge line 198 through the spool valve chamber 194.

Upon pressurization of the ducts 190, all the odd-numbered pumps P1, P3, and so on are pressurized to move pumpage into the next following even-numbered pumps. This movement continues until the probe structure 170 senses that the pump P1 is substantially purged and the probe structure 180 senses the pump P2 is substantially full. Thereupon, the actuators 176 and 186 develop sufficient force differential to overcome the static inertia of the system and displace the spool valve 176- to the right, in the position shown. Thereupon, the pressure duct 192 is connected to the ducts 196 to pressurize all the evennumbered pumps, while the odd-numbered pumps are relieved. In this manner, the system is pneumatically controllled to move pumpage, as over very great distances. Of course, it is to be appreciated that the actual control in various systems hereof may readily be electrical, hydraulic, pneumatic, mechanical or other. The basic principle being simply the synchronization of the pressurization and relief of the pump apparatus in coordination with the flow of the pumpage.

In some applications of the system hereof it may be desirable to gang several individual pumps for seqeun-tial operation so as to assure a uniform and constant flow of pumpage. One example of such a structure is shown in FIGURE 7, including two pumps 202 and 204 substantially as disclosed in FIGURE 4. The operation of these pumps in alternating sequence is accomplished by a spool valve structure 206 controlled by probe structures 208 and 210 acting through an electrical system 212.

In the stage of operation in which the structure of FIG- URE 7 is depicted, the pump 202 is purged and the pump 204 is full; the control system has not altered the cycle to start purging the pump 204. This reversal occurs when an alternating electrical timer 214 provides a control voltage to a switch 216 to energize a solenoid 218, which shifts the position of a spool valve 220, from left to right through a pivot arm 222.

The electrical timer 214 may comprise any of the wide variety of electronic or electromechanical timers and serves to sequence the operation of the system by alternately providing power to the switches 216 and 218. A change in the state of the timer, however, does not reverse the cycle of the system unless the switches 216 and 218 are set by the probes 208 and 210 to indicate the proper state of the pumps for a reversal. This state is shown in FIGURE 7, as the pump 202 is purged. Therefore, when the spool valve 220 moves to the right, the air passage 224 of the pump is connected through the spool valve chamber 226 to a pressure line 228. Simultaneously, the air passage 230 of the pump 202 is similarly connected to a relief passage 232. As a result, the pump 204 moves pumpage through a duct 240 and past a flipper valve 242 into a common channel 244. The valve 242 avoids possible back flow of the pumpage into the pump 202.

When the pump 204 is purged, the probe 210 closes the switch 218. This action will then energize a solenoid 246, providing the electrical timer 214 is energizing the switch 218. That is, the timer 214 affords a delay control to regulate the pace of operation so as to assure adequate time for each of the pumps to function.

Upon energization of the solenoid 246, the spool valve 220 is returned to the position in which it is shown thereby pressurizing the pump 202 from the line 228 to force pumpage out of the duct 250, and relieving the pump 204 through a relief passage 252. Thus, the cycle recurs.

In the various exemplary embodiments as described herein certain features are manifest. Specifically, it can be appreciated that the system is effective to control any of a wide variety of substance or pumpage, either by pumping the substance or by controlling the flow thereof as a valve action. Of course the latter structure may be pressure regulated to accomplish a nicety of control. Furthermore the simplicity of the system is an indication of its durability, ease of use and economy of manufacture. Of course, various other features and structural embodiments have been considered above and others will be readily apparent to one skilled in the art; however, the scope hereof is not to be accordingly limited but shall be interpreted in accordance with the claims set forth below.

What is claimed is: 1. A pump for forcefully displacing pumpage, between an intake and an outlet during cyclic loading and exhausting operations, comprising:

a housing means defining a closed chamber; a flexible duct member positioned in said chamber whereby to receive pumpage from said intake;

cyclic-operating means for initially collapsing one portion of said duct within said chamber, contiguous to said intake where-by to initiate an exhaust flow from said duct member; and

cylic-operating means for varying the fluid pressure within said housing whereby to provide a fluid pressure to alternately collapse and release the major other portion of said flexible duct whereby to force said pumpage out of said outlet.

2. A system according to claim 1 wherein said means for initially collapsing one portion of said duct comprises:

:a vertical mounting stlucture for said flexible duct whereby to develop a static head of said pumpage along said duct, which head is reduced contiguous to said intake.

3. A system according to claim 1 wherein said means 'for initially collapsing one portion of said duct comprlses:

an actuator means to engagingly collapse said one portion of said flexible duct.

4. A system according to claim 1 wherein said means for varying the pressure in said housing includes probe means to sense the state of collapse of said flexible .tube.

5. A system according to claim 4 wherein said flexible duct comprises 'a cylindrical member having one end connected to said input and the other end connected to said 'output, and further including a quantity of incompressible fluid contained between said housing and said flexible duct member.

6. A system comprising a plurality of structures as defined in claim 1, and including control means for said means for varying the pressure thereof, said control means :for alternately sequencing the operation of said means for varying the pressure.

7. A system according to claim 6 wherein said control means comprises a pneumatic structure for alternately supplying air under pressure to said structures.

8. A system according to claim 1 wherein said flexible duct comprises a cylindrical member having one end raflixed to said input and one end aflixed to said outlet, and wherein said means for varying the pressure includes means for sensing the state of collapse of said duct and means controlled thereby to supply air under pressure to said housing means.

9. A system according to claim 8 further including: a hopper connected to said intake and adapted to receive said pumpage; and blow out shield means fixed between said hopper and said intake to restrict the flow therebetween.

10. A system comprising a plurality of structures as defined in claim 9, and including control means for said means for varying the pressure thereof, said control means for alternately sequencing the operation of said means for varying the pressure.

References Cited- UNITED STATES PATENTS 2,412,397 12/1941 Harper 103148 2,478,568 8/1949 Coe 103-44 2,626,569 1/1953 Knudsen 103152 X 2,760,436 8/1956 Von Seggern 103-44 3,007,416 11/1961 Chilcls 103-148 X 3,048,121 8/1962 Sheesley 103152 3,250,226 5/1966 Voelker 103152 ROBERT M. WALKER, Primary Examiner.

Claims (1)

1. A PUMP FOR FORCEFULLY DISPLACING PUMPAGE, BETWEEN AN INTAKE AND AN OUTLET DURING CYCLIC LOADING AND EXHAUSTING OPERATIONS, COMPRISING: A HOUSING MEANS DEFINING A CLOSED CHAMBER; A FLEXIBLE DUCT MEMBER POSITIONED IN SAID CHAMBER WHEREBY TO RECEIVE PUMPAGE FROM SAID INTAKE; CYCLIC-OPERATING MEANS FOR INITIALLY COLLAPSING ONE PORTION OF SAID DUCT WITHIN SAID CHAMBER, CONTIGUOUS TO SAID INTAKE WHEREBY TO INITIATE AN EXHAUST FLOW FROM SAID DUCT MEMBER; AND CYLIC-OPERATING MEANS FOR VARYING THE FLUID PRESSURE WITHIN SAID HOUSING WHEREBY TO PROVIDE A FLUID PRESSURE TO ALTERNATELY COLLAPSE AND RELEASE THE MAJOR OTHER PORTION OF SAID FLEXIBLE DUCT WHEREBY TO FORCE SAID PUMPAGE OUT OF SAID OUTLET.

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