US3162324A

US3162324A - Pneumatic dispenser

Info

Publication number: US3162324A
Application number: US154178A
Authority: US
Inventors: Roy W Houser
Original assignee: Robertshaw Controls Co
Current assignee: Robertshaw Controls Co
Priority date: 1961-11-22
Filing date: 1961-11-22
Publication date: 1964-12-22
Anticipated expiration: 1981-12-22

Description

22, 1964 R. w. HOUSER 3,162,324

PNEUMATIC DISPENSER Filed Nov. 22. 1961 3 Sheets-Sheet 1 WASHER IN VEN TOR. ROY WALTER HOUSER BY 7/624, Emm "v fi jr- A TTORNE Y Dec. 22, 1964 R. w. HOUSER 3,162,324

PNEUMATIC DISPENSER Filed Nov. 22, 1961 5 Sheets-Sheet 2 I l8 Q sag 1. Villa!!! 1.] I l/ INVENTOR. ROY WALTER HOUSER A TTORN E Y5.

Dec; 22, 1964 R. w. HOUSER 3,162,324

PNEUMATIC DISPENSER Filed Nov. 22. 1961 3 Sheets-Sheet 3 8 INVEN TOR. ROY WALTER HOUSER 2718 1475; AM, smk

A TTORNE Y9.

United States Patent ()flfice 3,162,324 Patented Dec. 22, 1964 Delaware Filed Nov. 22, 1961, Ser. No. 154,178 9 Claims. (CI. 222--18) This invention relates to devices for dispensing a predetermined quant-ity of material, and is particularly concerned with a device for adding a selected amount of fluid detergent or other material to the wash or rinse water in an automatic washing machine during the operating cycle of the washing machine.

The invention is directed to a device for use in conjunction with a container or reservoir of fluid detergent or the like having an inlet through which a quantity of air can be admitted to displace a like quantity of detergent through an outlet connected to the tub of the washing machine. The pneumatic dispenser of this invention pumps a selected quantity of air into the reservoir to displace the desired amount of detergent from the container.

It is, therefore, an object of this invention to displace a selected quantity of material from a container by pumping any desired amount of air into the container.

Another object is to pump a selected quantity of air into a liquid container to dispense a predetermined quantity of the liquid from the container.

Another object is to automatically actuate a pump a selected number of cycles to pump a particular quantity of air into a container of liquid material to displace a like quantity of the material from the container.

The objects are attained by the provision of a hollow casing having a pump chamber and a motor chamber formed in its interior by a flexible diaphragm. Inlet and outlet passages controlled by check valves are provided in the pump chamber. Suction is intermittently applied to the motor chamber to cause the diaphragm to reciprocate in the casing and draw air through the inlet upon expansion of the pump chamber, and expel the air through the outlet when the diaphragm moves to contract the pump chamber. For controlling the pressure in the motor chamber, a pivoted valve alternately closes a vent port and a vacuum port upon each cycle of movement of the diaphragm. Interacting cam elements control the position of the valve and a torsion spring connected with the stem of one of the cams provide the force to actuate the device. Rotation of the stem from a neutral off position in which the spring is unstressed, causes the spring to provide a biasing force on the cam to actuate the valve. The amount of rotation of the stem from its neutral position determines the number of cycles of movement of the diaphragm.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a diagrammatic view illustrating the dispenser connected with a container of liquid detergent;

FIG. 2 is a sectional View of the dispenser with the pump chamber contracted;

FIG. 3 is a view taken on line 3-3 of FIGURE 2;

FIG. 4 is a view taken on line 44 of FIGURE 2;

FIG. 5 is a View taken on line 5-5 of FIGURE 2;

FIG. 6 is a sectional view similar to FIGURE 2 but showing the pump chamber expanded;

FIG. 7 is a view taken on line 7-7 of FIGURE 6;

FIG. 8 is a view taken on line 8-8 of FIGURE 6; and

FIG. 9 is an exploded perspective view of some of the internal parts of the dispenser.

Referring to FIGURES 2 and 6 of the drawings, the dispenser comprises a hollow casing 10 formed from a pair of

casing members

12 and 14 having a diaphragm 16 disposed therebetween.

Casing members

12 and 14 are joined together at their periphery by screws 18 with the peripheral edge of diaphragm 16 clamped between the casing members to provide a seal.

Diaphragm 16 divides the interior of the casing into a pump chamber 20 and a motor chamber 22. Provided in the rigid wall of the pump chamber 20 formed by casing member 12 is an outlet port 24 and an inlet port 26. Internally threaded

bosses

28 and 30 on the outer wall of casing member 12 adjacent outlet port 24 and inlet port 26, respectively, receive

fittings

32 and 34, each having a passage for fluid. Compressed between fitting 32 and the wall of casing member 12 is a gasket portion 38 (see FIG. 3) of a resilient flap valve 36. Fitting 32 forms a conical chamber 33 with casing member 12 to permit flap valve 36 to open outwardly with respect to pump chamber 20, or to the left as viewed in FIGURE 2. As illustrated in FIGURE 3, fiap valve 36 is larger in diameter than outlet port 24 which prevents the valve from opening into the pump chamber when the pump chamber is expanded as illustrated in FIGURE 6. Compressed between fitting 34 and easing member 12 is a second flap valve 37 having a gasket portion 39. Valve 37 is identical in construction to valve 36, however, inlet port 26 is larger in diameter than flap valve 37 so that valve 37 can open into chamber 20 upon expansion of the pump chamber. Accordingly, as diaphragm 16 moves to the right (the position illustrated in FIGURE 6) to expand pump chamber 20, fluid is drawn through inlet 26 with outlet 24 remaining closed; and as the diaphragm returns to the left (the position illustrated in FIGURE 2) to contract pump chamber 20, inlet port 26 is closed and outlet port 24 opens permitting the air to be expelled from the pump chamber.

Positioned in motor chamber 22 is a stop plate 46 having a side wall 48 extending from its periphery with a flange 50 formed at the peripheral edge of side Wall 48. Stop plate 46 is provided at its center with a flanged aperture 52. Formed in stop plate 46 is a plurality of abutments or stops 54 (see FIGURES 5 and 7) which are disposed in a circle about the stop plate 46.

Positioned against diaphragm 16 and motor chamber 22 is a back plate 56 with a raised aperture projection 58 formed at its center. Flange 50 of stop plate 46 and diaphragm plate 56 form seats for a compression spring 60, which biases diaphragm 16 to the left as viewed in FIGURE 2 to contract pump chamber 20, with the diaphragm positioned against the inner wall of casing member 12. Pump chamber 20 is shown expanded against spring 60 in FIGURE 6.

Casing member 14 is provided with a central opening 62 formed by flange 64. Flange 64 projects inwardly from a raised shoulder 66. Projecting from shoulder 66 is a cylindrical wall 68 providing a cavity 70. Mounted in motor chamber 22 is a valve actuating cam member 72 having a hollow stem 74 which projects through opening 62. Cam member 72 may be of plastic material, however the specific material is not critical to the operation of the device. Member 72 is provided with the rectangular cavities 84 of cam member 72. Lugs 88v can shiftflaterally within cavities 84 along the diameter of face 82, but maintain the ratchet spring 86 in a rotatably' fixed relationship with cam member 72. Accordingly, rotation of cam member '72 causes rotation of ratchet spring 86. Projecting from ratchet spring 86 is a pair of diametrically opposed stop tabs or lugs 90 and 92 which, as illustrated in FIGURES 5 and 7, are alternately engageable with one of the protuberances or stops 54 on stop plate 46. Centrally disposed in ratchet spring 86 is an aperture 94 which is provided with inwardly projecting

tabs

96 and 98 for a purpose to be described below.

Received in the raised portion 58 of diaphragm plate 56 is a hemispherical pivot rnember100 having a stem 102 projecting through the aperture of raised portion 58. Stem 102 is press-fitted into a recess 104 of a control cam 106 which projects through apertures 52 of stop plate 46, and is slidably received in the hollow stem 74 of valve actuating cam 72. Control cam 106 is preferably cylindricalsin shape and is provided with oppositely disposed slots 108 and 110. Slot 108 has an inclined end wall 112, and slot 110 is provided with an inclined end wall 114. As illustrated more clearly in FIGURES 5 and 7,

tabs

96 and 98 of ratchet member 86 are received respectively in slots 108 and 110.

Mounted on the inner wall of casing member 14 by screw 116 is a curved valve-lever 118 (FIGURES 4, 8 and 9); Formed on the inner edge of valve lever 118 is a, cylindrical cam follower 120. Cam follower 120 is biased into continuous engagementwithcam surface .76 of valve actuating cam 72 by spring 122 which is mounted on screw 116 and is biased into engagement with follower 120 by its engagement with a projection 124 formed on casing member 14.

Formed inthe wall of easing member 14 is an exhaust or atmosphere-port 128 and a vacuum port 130 (see FIG URES 4 and 8). Mounted on the free end of valve lever 118 is a valve element 132 which is provided with a machined flat surface which cooperates with the inner wall of easing member 14 toalternately seal vacuum port 130 and exhaust port 1-28. With reference to FIGURE 8, when cam follower. 120 is positioned in a depression 80, valve element 132 covers vacuum port 130. When cam follower 120 is positioned on the outer periphery of a projection 78 (FIGURE 4), valve element 132 seals exhaust port 128 and uncovers vacuum port 130.

With the mechanism described thus far, and with' vacuum port 130 connected with a source of vacuum 74 is provided with a keyway 133 and a notch 135 which receives cooperating projections on knob 134 to fixedly mount the stem and control knob against relative rotation. Cylindrical wall 68iis provided with a slot 136 for receiving one end 138 of a torsion spring 140. Torsion spring 140 has its other end 142 fixedly mounted in the plastic material of stem 174. Disposed between torsion spring 140 and shoulder 66 is a resilient sealing washer 144 and a spring seat washer .146. Clockwise rotation of control knob 134 Winds up torsion spring 140 which produces a biasing force on stem 74 tending to return valve actuating cam 72 to its original or neutral position.

Operation In FIGURE 1, the dispenser 10 is shown connected to a container of liquid detergent or the like. Container 40 has an inlet which is connected with a conduit 42 and an outlet 44 which is positioned over the tub of a washing machine. Conduit 42 is connected to outlet fitting 32 so thateach time air is pumped from chamber 20 through conduit 42, a certain quantity of detergent is dispensed from outlet 44' into the washer tub. Control knob 134 is positioned to cooperate with indicia on a control panel 148. Vacuum port 130 is'connected by'means of a conpressure, rotation of valve actuating cam 72 will cause i valve element 132 to reciprocate between

ports

130 and 128 to alternately subject motor chamber 22 to vacuum and atmospheric pressure. is uncovered, motor chamber 22 is subjected to atmospheric pressure and spring moves diaphragm -16 to the left to contractpump chamber 20, the position illustrated in FIGURE 2, since the pressures in chambers '20 and 22 are equal with inlet 26 of the pump'chamber being connected to atmosphere. When atmosphere port "128 is closed by valve element 132, motor chamber 22 is subjected tosvacuum pressure through port 130 which urges diaphragm 16 to the right to expand the pump chamber and draw air through inlet 26. As diaphragm 16 alter- 134 is fixedly mounted on the outer end of stem 74. Stem When atmosphere port 128 duit 150 to a source of vacuum.

In its neutral, or zero position withspring 140 unstressed, cam follower 120 is positioned in one of the grooves of cam surface 76 (see FIGURE 8). In this position, valve 132 covers vacuum port 130 and chamber 22 is exposed to atmospheric pressure through port 128.

When the washing machine is to be operated, the housewife selects the amount of detergent to be added to the wash water by rotating knob 134 in a clockwise direction by an amount corresponding to the desired quantity of detergent; This is facilitated by the markings on the control panel and cooperating markings on knob 134. For example, each number on the control panel 148 may correspond to some unit such as a tablespoon or a cup of detergent, so that when knob 134 is' rotated'to the numeral 3,. dispenserlt) will cause 3 units of detergent to be added. Rotation of knob 134 to the desired setting causes spring 140 to store energy tending to rotate valve actuating cam 72 in a counter-clockwise direction, and also causes cam'follower'120 tomove to the position illustrated in'FIGURE 4 where it is positioned'against one of the peaks 78 ofcam surface 76. This in turn moves valve 132 away from vacuum port 130 to its position closing atmospheric port 128. After the initial setting by the operator, cam member 72 is prevented from rotating by the engagement of stop tab 92 of ratchet spring 86 with a protuberance 54a onstop plate '46 (see FIG- URE 5). The resiliency of ratchet spring 86 permits tabs and 92 to override stops 54 when the operator rotates control knob'134, but when the knob is released, the force exerted by spring 140 is not sufficient to cause tab 92 to override the stops. v

After the initial setting by the operator, the parts are in the positions illustrated in FIGURES 2, .4,'and 5, and remain in this position until a certain point in the wash cycle is reached as determined by'thewashing machine controls (not shown), at'which point a vacuum signal is applied to port through conduit 150.

As vacuum pressure is admitted to chamber 22 through port 130, diaphragm 16 moves to the right to the position shown in FIGURE 6 causing air to be drawn into pump chamber 20 through inlet port 26. Cylindrical control cam 106 is carried to the'right with diaphragm 16, and tab 96 of ratchet spring 86 slides along groove 108 until it engages the inclined wall 112 of groove 108, "whereupon ratchet spring 86 is carnmed upwardly as viewed in FIGURES 2 and 6 ,by inclined surface 112 until stop tab 92 is disengaged from projection 54a, and stop tab 90 is moved mtoithe path of a projection 54b (FIGURE 7). When tab 92 disengages stop 54a, ratchet spring 86, valve actuating cam 72, and cylindrical control cam 1% all rotate due to the biasing force of spring 140 until stop tab 90 engages projection 54!; on stop plate 46 as shown in FIGURE 7. When stop 90 engages protuberance 54b, cam follower 120 comes to rest in a groove 80 in cam surface 76 causing valve 132 to move to its position covering vacuum port 130 and subjecting chamber 22 to atmospheric pressure through port 128. At this point, the parts are in the positions illustrated in FIGURES 6, 7 and 8.

As soon as port 128 is uncovered by valve 132, the pressures in chambers and 22 are equalized, and spring causes diaphragm 16 to move to the left to contract pump chamber 20 and expel the air in pump chamber 20 through outlet port 24 to container 40. As diaphragm 16 moves to the left, carrying with it cylindrical control cam 14%, the inwardly projecting tab 98 of ratchet spring 36 slides in groove until it engages inclined surface 114 whereupon ratchet spring 86 is cammed downwardly causing stop tab 90 to be disengaged from projection 54b and moving stop tab 92 into the path of a projection 540 (FIGURE 7), permitting

member

72, 86 and 106 to rotate until stop tab 92 engages projection 54c as shown by the broken line in FIGURE 7. When stop tab 92 engages protuberance 54c, the parts are in the positions illustrated in FIGURES 2, 4 and 7, with vacuum port uncovered by valve 132 to again subject motor chamber 22 to vacuum pressure.

The above described cycle of operation is repeated until torsion spring returns the parts to the neutral position. With each cycle of expansion and contraction of the pump chamber, a quantity of detergent is dispensed from container 40 corresponding to the amount of air expelled from pump chamber 20. Therefore, by selecting the number of cycles of pump operation, the desired amount of detergent is automatically added to the wash water at the appropriate stage of the wash cycle.

While a specific example of the invention has been described for purposes of illustration, it will be understood by those skilled in the art that various modifications can be made without departing from the scope of the invention as defined by the appended claims.

What is claimed is:

1. A pneumatic dispenser comprising;

a hollow casing,

a diaphragm dividing the interior of the easing into a pump chamber and a motor chamber,

means biasing said diaphragm to contract said pump chamber,

a valve in said motor chamber having a first position subjecting said motor chamber to a pressure less than the pressure in the pump chamber to expand the pump chamber, and a second position to subject the chambers to equal pressures to contract the pump chamber,

valve actuating means operable in response to contraction and expansion of the pump chamber to actuate the valve to said first and second positions, respectively,

and means for setting said valve actuating means in a selected starting position with said valve in said first position, said valve actuating means thereafter alternately moving said valve between said positions a selected number of cycles with the valve coming to rest in said second position.

2. A pneumatic dispenser comprising;

a hollow casing,

a diaphragm dividing the interior of the casing into a pump chamber and a motor chamber and being movable in response to differential pressures between said chambers to expand said pump chamber,

means biasing said diaphragm to contract said pump chamber,

valve means in said motor chamber movable between a first position in which said motor chamber is sub- 6 jected to a pressure less than the pressure in the pump chamber to cause said diaphragm to expand said pump chamber against said biasing means, and a second position in which the pressures in said chambers are equal, each cycle of movement of said valve means causing said diaphragm to move through one cycle to expand and contract said pump chamber,

a valve operating cam rotatably mounted in said motor chamber and operative upon rotation to alternately move said valve means between said first and second positions,

stop means engageable by said valve operating cam to prevent rotation of said valve operating cam,

and a control cam connected to said diaphragm,

said valve operating cam being alternately movable into andout of engagement with said stop means by said control cam upon each cycle of movement of said diaphragm permitting limited rotation of said valve operating cam to move said valve means between said positions.

3. A pneumatic dispenser as defined in claim 2 including;

spring means on said casing biasing said valve operating cam to a neutral position with said valve means in the second position,

and an operating knob connected with said valve operating cam to rotate said valve operating cam against the bias of said spring to a selected position with said valve means in its first position, said diaphragm thereafter expanding and contracting said pump chamber a selected number of cycles until said valve operating cam returns to its neutral position.

4. A pneumatic dispenser comprising;

a hollow casing,

a diphnagm dividing the interior of the easing into a pump chamber and a motor chamber and being movable in response to differential pressure between said chambers to expand said pump chamber,

means biasing said diaphragm toward a position contracting said pump chamber when the pressure in said chambers are equal,

valve means in said motor chamber movable between a first position in which the pressure in said motor chamber is less than the pressure in said pump chamber causing the diaphragm to expand the pump chamber, and a second position in which the pressures in said chambers are equal, each cycle of movement of said valve means between said first and second positions causing one cycle of movement of said diaphragm to expand and contract said pump chamber,

a valve operating cam rotatably mounted in the motor chamber and operative upon rotation to move said valve member alternately between said first and second positions,

a control cam connected to said diaphragm and operative to move said valve operating cam into and out of engagement with said stop means upon each cycle of movement of said diaphragm permitting limited rotation of said valve operating cam and moving said valve means through one cycle between said positions,

and means for rotating said valve operating cam to a selected starting position in which said valve means is in said first position, said diaphragm thereafter expanding and contracting said pump chamber a selected number of cycles, said valve means thereafter coming to rest in said second position.

5. A pneumatic dispenser comprising;

a hollow casing,

a diaphragm dividing the interior of the easing into a pump chamber and a motor chamber and being 7 movable in response to differential pressures between said chambers to expand and contract said pump chamber,

means biasing said diaphragm to contract the pump chamber, valve means in said motor chamber movable between a first position to subject said motor chamber to a pressure less than the pressure in the pump chamber .and a second position to subject the chambers to equal pressures,

a valve operating cam rotatably mounted in said motor chamber operative upon rotation to move said valve means alternately between said positions.

and a control cam interconnecting said diaphragm and said valve operating cam,

a spring biasing the valve operating camto a neutral position with the valve in the second position,

a plurality of a'butrnents, v

ratchet means mounted for rotation with'said valve operating cam and normally engaging one of, said abutments preventing rotation of said valve operating cam, i

said ratchet means being movable out of engagement with said one abutment by said control cam upon expansion of said pump chamber and into engagement with another of said abutments by said control cam upon contraction of said pump chamber permitting limited rotation of said rotatable cam with each cycle of movement of said diaphragm,

and a manually operable control knob on said hollow stem for rotating said valve operating cam against" the bias of said spring a selected number of revolutions to move said valve means to said first position,

said diaphragm expanding and contracting said pump chamber a selected number of cycles until said spring returns said valve operating cam and 'said valve means to the neutral position.

6. A pneumatic dispenser comprising;

a hollow casing, I I

a diaphragm dividing the interior of the easing into a pump chamber and a motor chamber and being movable between said chambers to expand and contract said pump chamber,

means biasing said diaphragm to contract said pump chamber, g a

an atmosphere port and a vacuum port in said motor chamber,

a valve insaid motor chamber movable between a m first position closing said atmospheric port 'to' subject said motor chamber to vacuum pressure and a second position closing said vacuum port to sub-' ject said motor chamber to atmospheric pressure causing said diaphragm to expand and contract said pump chamber to expel fluid therefrom, a valve operating cam rotatably mounted in the motor chamber operative upon rotation to alternately move said valve between its first and second positions,

said valve operating cam having a hollow stem projecting through the wall of the motor chamber to the exterior of the casing, V

a spring biasing said valve operating oath to a neutral position with the valve in its second position,

an apertured stop plate in the motor chamber having a plurality of circumferentially spaced stop members thereon,

a ratchet member mounted on said valve operating carn' engageable with ,said stop members to prevent rotation of said valve operating cam,

a control cam slidable in said hollow stem and connected to the diaphragm, said ratchet member being movable by said control a cam into and out of engagement with said'stop members upon expansion and contraction of said pump 8, chamber by said diaphragm to permit said valve operating cam to rotate between saidzstop members and move said valve between said first and second positions,

and an operating knob on said hollow stem for rotating said valve operating cam to a selected position with the valve in its first position, said diaphragm thereafter expanding and contracting said pump chamber to dispense a selected amount of fluid through said pump chamber until said spring returns said valve, operating cam to its neutralposition.

7. A pneumatic dispenser comprising;

a pair of chambers separated by a pressure responsive wall movable in response to pressure ditferentials between the chambers,

valve actuating means movable between a neutral position and a selected oneof a plurality of starting positions, 7

valve means in one of said chambers movable between a first position to cause said one chamber to contract and the other chamber to expand, and a second position causing said one chamber to expand and the other chamber to contract,

said valve means being operably engaged with said valve actuating means and held in said first position by said valve actuating means in its neutral position and actuated to said second position upon movement of valve actuating means to its selected starting position,

said valve actuating means being operable to shift said valve means between said first and second positions a selected number of cycles dependent upon the starting position of the valve actuating means upon return movement of the valve actuating means from the starting position to the neutral position.

8. A pneumatic dispenser comprising;

a pair'of chambers separated by a pressure responsive wall movable to expand and contract the chambers,

valve actuating means movable between a neutral position and a starting position,

means operative upon movement of the valve actuating means from its neutral position to its starting position to urge the valve actuating means to return to the neutral position,

valve means in one of said chambers movable between a first position causing said one chamber to contract and the other chamber to expand, and a second position causing said one chamber to expand and the other chamber to contract,

said valve being held in said first position by said valve actuating means in its neutral position, and actuated to said second position by move- 'ment of the valve actuatingmeans from the neutral to starting position, and thereafter being a returned to the first position by return movement of the valve actuating means from the starting position to the neutral position,

9. A pneumatic dispenser comprising;

a pair of chambers separated by a pressure responsive movable wall,

a ring of circumferentially spaced stop members in one of said chambers,

actuating means mounted inisaid one chamber for rotation relative to said ring of stop members,

stop lug means carried by said actuating means engageable with said stop members to restrain said actuating means against rotation,

valve means in said onechamber movable by rotation of said valve actuating means between a first position causing said one chamber to contract and the other chamber toexpand, and a second position causing said one chamber to expand and said other chamber to contract,

9 1G and control means interconnecting said movable Wall stop members to actuate said valve between said and said actuating means operable upon expansion first Second Positionsof said other chamber to release said stop lug mean References Cited in the file of this patent from one of the stop members and shift it into the 5 UNITED STATES PATENTS path of another of said stop members, 1,219,938 r Hamilton Man 20 1917 said valve actuating means rotating between said 1,912,203 Hueber et a1 May 30, 1933

Claims

1. A PNEUMATIC DISPENSER COMPRISING; A HOLLOW CASING, A DIAPHRAGM DIVIDING THE INTERIOR OF THE CASING INTO A PUMP CHAMBER AND A MOTOR CHAMBER, MEANS BIASING SAID DIAPHRAGM TO CONTRACT SAID PUMP CHAMBER, A VALVE IN SAID MOTOR CHAMBER HAVING A FIRST POSITION SUBJECTING SAID MOTOR CHAMBER TO A PRESSURE LESS THAN THE PRESSURE IN THE PUMP CHAMBER TO EXPAND THE PUMP CHAMBER, AND A SECOND POSITION TO SUBJECT THE CHAMBERS TO EQUAL PRESSURES TO CONTRACT THE PUMP CHAMBER, VALVE ACTUATING MEANS OPERABLE IN RESPONSE TO CONTRACTION AND EXPANSION OF THE PUMP CHAMBER TO ACTUATE THE VALVE TO SAID FIRST AND SECOND POSITIONS, RESPECTIVELY, AND MEANS FOR SETTING SAID VALVE ACTUATING MEANS IN A SELECTED STARTING POSITION WITH SAID VALVE IN SAID FIRST POSITION, SAID VALVE ACTUATING MEANS THEREAFTER ALTER-