US3229862A - Liquid dispensing apparatus - Google Patents

Description

Jan. 18, 1966 c DAWSON 3,229,862

LIQUID DISPENELING APPARATUS Original Filed March 9, 1962 5 Sheets-Sheet l Jan. 18, 1966 J. c. DAWSON 3,229,862

LIQUID DISPENSING APPARATUS Original Filed March 9, 1962 5 Sh -S ee 2 FIGS. F164.

Jan. 18, 1966 J. c. DAWSON LIQUID DISPENSING APPARATUS 5 Sheets-Sheet 5 Original Filed March 9, 1962 Ill! United States Patent 3,229,862 LIQUID DISPENSING APPARATUS Joseph Carl Dawson, St. Louis, Mo. (93 Ford Lane, Hazelwood, Mo. 63142) Original application Mar. 9, 1962, Ser. No. 178,731, now Patent No. 3,187,956, dated June 8, 1965. Divided and this application Jan. 8, 1965, Ser. No. 424,279

18 Claims. (Cl. 222318) This is a division of my copending application, Serial No. 178,731, filed March 9, 1962, now Patent No. 3,187,- 956 of June 8, 1965.

This invention relates to liquid dispensing apparatus, and more particularly to apparatus for dispensing measured dosages of a liquid fumigant or the like.

The invention involves improvements upon the apparatus shown in my U.S. Patent Re. 25,172, reissued May 15, 1962. In the apparatus shown in said patent, there is provided a vertical measuring cylinder having an inlet at its lower end and an outlet at its upper end. Liquid under pressure is supplied to the inlet. The cylinder has a valve seat at its upper end, and contains a valve member adapted to sink to the lower end of the cylinder. A delivery hose extends from the outlet and has a manually operable delivery valve at its end. A by-pass having a restriction therein is provided around the cylinder. When the delivery valve is opened, pressure causes the valve member to rise and force liquid out through the delivery hose, the valve member ultimately engaging the valve seat to cut off delivery from the cylinder. On closing the delivery valve, pressure is equalized above and below the valve member via the by-pass, and the valve member sinks back to the lower end of the cylinder. If the delivery valve should not be closed immediately upon seating of the valve member against the valve seat, some liquid may leak on by through the by-pass, and increase the dosage of liquid delivered. In some instances, this may be undesirable, and accordingly, one of the objects of this invention is the provision of an apparatus of the class described which provides for pressure equalization in such manner as to avoid the possibility of delivery of an overdose. Also, in the apparatus shown in said patent, in which return of the valve member is by gravity, an upright arrangement of the measuring cylinder is in order, and return of the valve member may be slower than desired. Accordingly, a further object of the invention is the provision of apparatus of the class described in which the valve member is positively returned, rather than returned by gravity, which tends to speed up the return and enables the measuring cylinder to be mounted in any desired position, such as in horizontal position. Such a positive return type of device may be used in apparatus with a by-pass such as shown in said patent, if the possibility of a slight overdose is not critical, or may be used in the improved system of this invention which provides for pressure equalization in such manner as to avoid the possibility of an overdose. Still another object of the invention is the provision of means for adjusting the apparatus to deliver different dosages. Other objects and features will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which several of various possible embodiments of the invention are illustrated,

FIG. 1 is a view in elevation of a liquid dispensing apparatus of this invention;

FIG. 2 is an enlarged fragment of FIG. 1, with parts broken away and shown in section, showing details of a delivery valve;

FIG. 3 is an enlarged fragment of FIG. 1, with parts broken away and shown in section, showing details of a measuring cylinder;

FIG. 4 is a view showing a modification;

FIG. 5 is a view in elevation of an alternative embodirnent;

FIG. 6 is an enlarged section taken on line 6-6 of FIG. 5 showing the measuring cylinder arrangement of FIG. 5;

FIG. 7 is an enlarged partial section showing the measuring cylinder of FIG. 6 used in the FIG. 1 apparatus; and

FIG. 8 is a view showing a modification providing for adjustment to deliver difierent dosages.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to FIG. 1 of the drawings, a liquid dispensing apparatus of this invention is shown to comprise a portable support generally designated 1 comprising a base 3, upstanding legs 5, a brace 7, and a carrying handle 9 extending between the upper ends of the legs 5. Mounted between legs 5 are a pressurized gas (air) supply tank 11 and a tank 13 which may be filled with liquid fumigant. The tanks 11 and 13 are adapted to be held between legs 5 by metal straps 15. Mounted on the base 3 of the support is an assembly designated in its entirety by the reference character 17 and including a vertical measuring cylinder 19, and an air chamber 21 having its lower end in communication with the lower end of the cylinder 19.

Pressure tank 11 is connected to the fumigant tank 13 by piping 23 in which is located a pressure regulator 25 and pressure gauge 27, and a hose 29 extending from the regulator to the upper end of the fumigant tank. Cutotfs are provided as indicated at 31 and 33. The pressure tank is adapted to be pressurized by closing the valve 31 and connecting a supply hose (not shown) which is connected to a suitable pressurizing source (also not shown) to an inlet nipple 35. Nipple 35 includes a check valve adapted to open under pressure in the supply hose.

The measuring cylinder 19 comprises a tube 37 having an upper end head 39 and a lower end head 41. The lower end head 41 has an upwardly extending nipple 43 (FIG. 3) projecting upwardly into the tube, and has a passage 45 for flow of liquid upward through the nipple into the tube. Attached to the lower end head 41 is the stem of a T 47. A short length of pipe 48 extends from one side of the T 47 and has a T 49 secured to one end thereof. The stem of T 49 is threaded in the lower end of the air chamber 21. The other end of T 49 is connected to the lower end of fumigant tank 13 by a pipe 50, an elbow 51 and a pipe 52. A by-pass hose 53 (which may be a plastic hose such as polyethylene hose) is secured at one end thereof to the other side of the T 47. The other end of by-pass hose 53 is secured to a manually operable delivery valve 55 which will be hereinafter described.

The upper end head 39 of the tube 37 is formed with an annular shoulder 57 which constitutes a valve seat. An elbow 59 is connected to the upper end head 39. A delivery hose 61 (which may be a plastic hose such as a polyethylene hose) extends from the elbow 59 to the manually operable delivery valve 55.

A valve member generally designated 63 is vertically movable in tube 37 of cylinder 19. This valve member 63 may be similar to that shown in US. Patent Re. 25,172, comprising a weight 65 (a body of lead, for example), having at its upper end two vertically spaced horizontal discs 67 and 69 which may be made of plastic such as polyethylene. The upper disc 67 is a valve disc engageable with shoulder or seat 57 to cut off flow from the upper end of the cylinder 19 to the delivery hose 61.

The lower disc 69 serves as a piston whereby the valve member 63 is adapted to rise in the cylinder from an initial position in the lower end of the cylinder (FIG. 3) in response to a pressure drop in the cylinder above the valve member 63. Both discs have a relatively loose fit in the cylinder so that the valve member 63, without undue impedance, is adapted to sink to the lower end of the cylinder, under the gravity bias of its weight upon equalization of pressure above and below the valve member 63. This is because in this embodiment the weight of the volume of the liquid in the cylinder displaced by the valve member (which ismade of lead, for example) is less than the weight of the valve member. Accordingly, the weight of the volume of the liquid in the cylinder displaced by the valve member is such in relation to the weight of the valve member that the valve member tends to move toward the inlet end of the cylinder. At the lower end of the weight 65 is an inverted cup 71 which covers nipple 43 when the valve member 63 is at the lower end of the cylinder 19.

The manually operable delivery valve 55 (FIG. 2) comprises a valve body 73 threaded into a handle 75. Valve 55 is provided with a transfer port 77, a bypass port 79 and a delivery outlet 81. A passage 83 is provided in valve body 73 and is counterbored at 85. Threaded into the counterbore 85 is a cup-shaped fitting 87 in which a manually operable button 89 is slideably mounted. A valve member 91 has a stem 93 threaded into the lower end of button 89. The fitting 87 is pro vided with ports 95 which communicate with a port 97 in the valve body 73. Port 97 is connected to the delivery outlet 81. The valve member 91 is biased toward a seat 99 on the bottom of the fitting 87 by a spring 101 extending between the button 89 and the upper surface of the bottom of the cup-shaped fitting 87. A second valve member 105 is mounted in passage 83. Valve member 105 is biased by a spring 107 towards a seat 109 surrounding the bypass port 79. The valve member 105 is adapted to be held against seat 109 by the valve member 91 when the button 89 is pushed downwardly as viewed in FIG. 2.

A delivery nozzle 114 is threaded into delivery outlet 81. The bypass hose 53 is connected to the bypass port 79 by a fitting 111. The delivery hose 61 is connected to the transfer port 77 by a fitting 113.

Assuming the pressure tank to be pressurized and the valves 31 and 33 open, operation is as follows:

Liquid under pressure is supplied to bypass hose 53.

This pressurized liquid forces the valve member 105 in the delivery valve 55 upwardly as viewed in FIG. 2 against the .bias of spring 107. The liquid in bypass hose 53 passes through passage 83 and back through port 77 and delivery hose 61 to prime the apparatus. After the pressure on both sides of the valve member 105 is equalized spring 107 will force it toward engagement with seat 109.

When the button 89 is manually pushed downwardly as viewed in FIG. 2, communication is established between the transfer port 77 and the delivery outlet 81 and the valve member 91 is moved down toward valve member 105 to hold the latter against seat 109 whereby communication is blocked between ports 77 and 79. With transfer port 77 and outlet 81 .in communication, the pressure in the delivery hose 61 is released, and there is a pressure drop in the cylinder 19 above the valve member 63, which at this time is at the lower end of the cylinder 19 with cup 71 covering nipple 43. Accordingly, the valve member 63 is driven upwardly by the pressure below it and rises to the upper end of the cylinder 19. As it rises, it forces liquid out the upper end of the cylinder 19, through the delivery hose 61 and delivery valve 55 to deliver a measured dose of liquid through the nozzle 114 of the delivery valve 55. Upon rising to the upper end of the cylinder 19, the valve disc 67 engages the seat 57 to cut off delivery of any liquid through the delivery hose 61. As long as button 89 is held down, port 79 is blocked so that no liquid can pass from bypass hose 53 to the nozzle. ency for the operator immediately to release the button upon cut-off of delivery through hose 61.

Upon release of the button 89, valve member 91 closes on seat 99 and valve member is released. Pressure from the bypass hose 53 forces the valve member 105 upwardly as viewed in FIG. 2 to establish communication between the ports 79 and 77. The liquid flows from the bypass hose 53 through the valve 55 and delivery line 61 to the upward end of the cylinder 19, and the pressure above and below the valve member 63 equalizes, whereupon the valve member 63 sinks to the lower end of the cylinder, 19. When it reaches the lower end of the cylinder, the apparatus is ready for the next operation.

With liquid under pressure in the pipe 50, a supply of compressed air is maintained in the air chamber 21 above the liquid in the chamber. This chamber being close to the cylinder 19, the compressed air therein'is effective on opening the delivery valve 55 for application of pressure to the liquid at the lower end of the cylinder 19 to offset the inertia of liquid and the loss of head, if any, in the pipe 50, elbow 51 and pipe 52 from the liquid fumigant tank 13. The air chamber may not be essential when the fumigant tank 13 is located close to the cylinder 19 as in the embodiment shown in FIG. 1, but would be particularly useful in a case where the piping or a connecting hose between the fumigant tank and the cylinder 19 is of such length or is of such character as to cause substantial loss of head.

FIG. 4 shows a measuring cylinder arrangement which may replace the measuring cylinder 19 shown in ;FIG. 3. The measuring cylinder 19 in FIG. 4 is inverted or reversed so that the nipple 43 extends downwardly into the tube from the end head 41 and the seat 57 is at the lower end of the cylinder. The T 47 is connected to the end head 41 and is connected on one side to the pipe 48 and on the other side to the bypass hose 53. The elbow 59, which is at the lower end of the cylinder in the embodiment shown in FIG. 4, is connected to the delivery hose 61. Instead of a weighted valve member 63,

a floating valve member 115 is employed. That is, the weight of the liquid displaced by the valve member 115 is greater than the weight of the valve member so that the valve member 115 will rise upon equalization of pres.- sure on both sides thereof. Accordingly, the weight of the volume of the liquid in the cylinder displaced by the valve member 115 is such in relation to the weight of the valve member that the valve member 115 tends to move (rise) toward the inlet end of the cylinder.

The construction shown in FIG. 5 includes the same support 1 pressure tank 11 fumigant tank 13 and the connections between pressure tank 11 and fumigant tank 13. The lower end of the fumigant tank 13 is connected to a horizontal measuring cylinder 117 by an elbow 119.

As shown, a bypass 121 is provided for the cylinder 117. In the bypass 121 there is an adjustable valve 123. This,

may be a conventional needle valve, for example.

The cylinder 117 comprises a tube 125 having an inlet end 127 and an outlet end 129. A peripheral flange 131 is provided internally of tube 125 adjacent to but spaced inward from the inlet end 127. A nipple 133 is threaded into the outlet end 129 of the tube 125 and extends toward the inlet end 127 of the tube. The inner end of this nipple constitutes a valve seat 135. The outer end of the nipple 133 is connected to one side of a T 137. The other side of the T 137 is connected to a delivery hose 139. By-pa-ss valve 123 has one end secured to an elbow 141 and its other end connected to the inlet end 127 of the cylinder 117 by a conduit 143. The other Consequently, there is no particular urgend of elbow 141 is connected to the stem of T 137 to complete the by-pass 121.

A cup-shaped valve member generally designated 145 is movable in the tube 125 of cylinder 117. Valve member 145 is biased toward the inlet end of the cylinder 117 by a spring 147 extending between the bottom of the cup-shaped valve member 145 and the outlet end of the cylinder 117. Spring 147 surrounds the nipple 133. The location of the annular flange 131 prevents the valve member 145 from cutting ofi the by-pass 121. The open end of the valve member 145 is adapted to be seated on flange 131 by spring 147 upon equalization of pressure on both sides of the valve member. Valve member 145 is adapted to be moved toward the outlet end 129 of the cylinder from an initial position at the inlet end of the cylinder (illustrated in FIG. 6) in response to a pressure drop on the outlet side of the valve member 145. A hole 149 is provided in the valve member wall so that the valve member 145, without undue impedance, is adapted to move to the inlet end 127 of the cylinder under the bias of the springs 147 upon equalization of pressure on both sides of the valve member 145. 7 At the outer end of the delivery hose 139 is a manually operable delivery valve 151 (which may be the same as shown in Us. Patent Re. 25,172) having a delivery nozzle 153 and a manually operable lever 155 for opening it. The delivery valve includes a check valve 157 adapted to open in the direction indicated by the arrow in FIG. 5 under the pressure in the delivery hose when the delivery valve is opened.

Operation of the embodiment shown in FIGS. 5 and 6 is as follows:

The pressure at the inlet end of the cylinder 117 is preferably regulated to be, for example, about fifty to seventy-five pounds per square inch. When such pressure is employed, the check valve 157 is one that is adapted to open under about 10 lbs. per sq. inch pressure in the delivery hose line 139. The by-pass valve 123 is opened wide to allow liquid to flow freely through the by-pass 121 to the delivery hose 139 to prime the apparatus. Then the by-pass valve 123 is turned down to provide a restriction in the by-pass 121 such as to effecta pressure drop in cylinder 17 on the outlet side thereof whenever the manually operable delivery valve 151 is operated.

Thus, when the delivery valve 151 is operated, the pressure in the delivery hose 139 is released, and there is a pressure drop in the cylinder 117 on the outlet side of the valve member 145, which at this time is at the inlet end of the cylinder with the open end of the valve member 145 engaging the flange 131. The restriction provided in the by-pass 121 by valve 123 is sutficiently small to preclude such flow of liquid through the by-pass as would materially reduce this pressure drop. Accordingly, the valve member 145 is driven toward the outlet end of the cylinder 117 by the pressure on the inlet side of the valve member and moves to the outlet end of the cylinder 117. As it moves, it forces liquid out of the outlet end of the cylinder 117 and through the delivery hose 139 to deliver a measured dose of liquid through the nozzle 153 of the delivery valve 151. Upon moving to the outlet end of the cylinder 117, the bottom of the cup-shaped valve member 145 engages the seat 135 to cut off delivery (except for the small amount that may leak through the restriction in the by-pass provided by the valve 123). Upon such cutoff, the pressure in delivery hose 139 drops below that required to maintain check valve 157 open, and this check valve closes to keep the delivery hose primed, even though the operator should not at once releasethe lever 155 of the delivery valve 151 to allow it to close. However, the cut-off is readily sensed by'feel so that an alert operator may immediately release the lever 155 to close the delivery valve 151. 1 With the delivery valve 151 closed, pressure from the elbow 119 bleeds through the restriction in by-pass 121 provided by valve 123, and the pressure on the inlet and outlet sides of the valve member equalizes, whereupon the valve member 145 is moved to the inlet end of the cylinder 117 by the spring 147. When the open end of the valve member 145 reaches the flange 131, the apparatus is ready for the next operation.

If positive cut-ofl? is desired, the cylinder 117 and springreturned valve member 145 such as shown in FIG. 6 may be incorporated in the FIG. 1 embodiment in place of the cylinder 19 and gravity-returned valve member 63 shown in FIGS. 1 and 3. FIG. 7 illustrates the cylinder 117 and valve member 145 as they would appear when so substituted in the FIG. 1 embodiment. An elbow 159 connects the fumigant tank 13 to the inlet end of the cylinder 117. By-ipass hose 53 is connected between the inlet end of the cylinder 117 and the inlet port 79 of the manually operable delivery valve 55. The delivery hose 61 is connected between the outlet end of cylinder 117 and the inlet port 77 of the delivery valve 55. In operation, the FIG. 7 embodiment functions in substantially the same manneras the embodiments shown in FIGS. 1-4. Upon pushing button 89 downwardly the inlet port 77 is placed in communication with the delivery port 81 so as to effect a pressure drop on the outlet side of the valve member 145. Accordingly, the pressure on the inlet side of the valve member 145 forces the valve member toward the outlet end of the cylinder 117 against the return bias of spring 147. When valve member 145 engages seat 135, delivery through the delivery hose 61 is cut off. When the button 89 is released, the inlet ports 77 and 79 are placed in communication to equalize the pressure on both sides of the valve member 145, whereupon the valve member is returned by spring 147 toward and into engagement with the flange 131.

It will be seen that in each of the embodiments shown in FIGS. 3, 4 and 7 the valve member is biased toward the inlet end of the cylinder when the pressure on both sides of the valve member is substantially equalized and the valve member moves towards the outlet end of the cylinder in response to a pressure dnop on the outlet side of the valve member.

FIG. 8 shows another possible modification providing for adjustment to vary the amount :of liquid delivered. Here a measuring cylinder 19 such as shown in FIGS. 1 and 3 is provided. A valve member 145 such as shown in FIG. 6 may be used, with or without a spring such as shown at 147 in FIGS. 6 and 7. Instead of using a T at the inlet end of the cylinder, there is used a cross fitting 171. One arm of this fitting is coupled to the inlet end of the cylinder. A packing gland 173 is threaded in the end of the opposite arm of the fitting, and a stop rod 172 extends slidably through the gland. This rod has a handle 175 at its outer end, and reaches axially through nipple 43 into the cylinder 19 (with space around the rod for flow of liquid). The valve member 145 is engageable with the inner end of the rod to determine the retracted position of the valve member, and by loosening the gland, sliding the rod in or out and tightening the gland, the stroke of the valve member 145 may be varied to vary the dosage delivered on a pressure stroke of the valve member 145., In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. Apparatus for dispensing measured charges of a liquid, comprising a measuringcylinder having an inlet at one end and an outlet at its other end, a line connected to the cylinder inlet for supplying liquid under pressure to the cylinder, said cylinder having a valve seat at its outlet' end, arelatively loosely fitting valve member movable in said cylinder, said valve member being adapted to move toward the inlet end of the cylinder on equalization of pressure on both sides of the valve member and to move toward the outlet end of the cylinder in response to a pressure drop on the outlet side of the valve member thereby to force a measured charge of liquid through the cylinder outlet, said valve member being engageable with the valve seat at the outlet end of the cylinder so as to cut off flow from the cylinder, a delivery valve having. an inlet port and an outlet port, a valve element operatively mounted in said delivery valve for optionally establishing communication between the inlet and outlet ports thereof, a conduit interposed between the cylinder outlet and the. inlet port of the delivery valve, a bypass valve means having a first port in communication with the inlet port of the delivery valve, and a second port in communication with the inlet of the cylinder, said bypass valve means being adapted to substantially interrupt communication between said first and second ports thereof when said delivery valve establishes communication between its inlet and outlet ports.

2. Apparatus as set forth in claim 1 including a spring biasing said valve member in said cylinder toward the inlet end of the cylinder.

3. Apparatus as set forth in claim 1 wherein said cylinder has an upper end and a lower end, the weight of the volume of the liquid in the cylinder displaced by the valve member therein being such in relation to the Weight of the valve member that the valve member tends to move toward the inlet end of the cylinder.

4. Apparatus as set forth in claim 1 further comprising means extending into said cylinder from its inlet end engageable by said valve member for determining a retracted position of said valve member-and axially adjustable relative to the cylinder for varying the stroke of said valve member.

5. Apparatus for dispensing measured dosages of a liquid, such as liquid fumigant, comprising a cylinder having an inlet at one end and an outlet at its other end, a line for supplying liquid under pressure to the cylinder having a connection to the cylinder inlet, said cylinder having a valve seat at its outlet end, a movable valve member in the cylinder, said valve member being adapted to move toward the inlet end of the cylinder on equalization of pressure on both sides of the valve member, said valve member being adapted to move toward the outlet end of the cylinder in response to a pressure drop on the outlet side of the valve member and force liquid out through the cylinder outlet, said valve member, upon moving to-the outlet end of the cylinder, being engageable with said valve seat to cut oil flow from said outlet end of the cylinder, a manually operable delivery valve having first and second ports and an outlet, a delivery hose connected between the cylinder outlet and said-first port, a by-pass hose connected between the cylinder inlet and said second port, said delivery valve having valve means movable between a delivery position wherein the second port is blocked and said first port is connected to the de' livery valve outlet to effect a pressure drop in the cylinder on the outlet side of said valve member whereupon the valve member moves toward the outlet end of the cylinder to force a measured dose of liquid through the cylinder outlet, the delivery hose andthe delivery valve outlet, and a by-pass position wherein said deliveryvalve outlet is closed and said ports are in communication with one i another to provide for equalization of pressure on both sides of said valve member after the latter has moved into engagement with said valve seat, whereupon the valve member moves to the inlet end of the cylinder. 2

6. Apparatus as set forth in claim 5 including a spring biasing said valve member in said cylinder toward the inlet end of the cylinder.

7. Apparatus as set forth in claim 5 wherein said cylinder has an upper end and a lower end, the weight of the volume of the liquid in the cylinder displaced by the valve livery valve means comprises a first delivery valve member biased toward a first position wherein communication is blocked between said first port and said delivery valve outlet and manually movable to a second position wherein communication is established between said first port and said delivery valve outlet, and a second delivery valve member adapted to be biased by the pressure of the liquid in said by-pass hose toward an open position wherein communication is established between said ports and adapted to be held by said first delivery valve member in i a closed position wherein communication is blocked between said ports when the first delivery valve member is in its second position.

10. Apparatus as set forth in claim 9 including a spring biasing said valve member in said cylinder toward the inlet end of the cylinder.

11. Apparatus as set forth in claim 9 wherein said cylinder has an upper end and a lower end, the weight of the volume of the liquid in the cylinder displaced by the valve member therein being such in relation to the weight of the valve member that the valve member tends to move toward the inlet end of the cylinder.

12. Apparatus for dispensing measured dosagesof a liquid, comprising a cylinder having an inlet at one end and an outlet at its other end, a line for supplying liquid under pressure to the cylinder having a connection to the cylinder inlet, said cylinder having a valve seat at its outlet end, a movable valve member in the cylinder, said valve member being adapted to move toward the inlet end of the cylinder on equalization of pressure on both sides of the valve member, said valve member being adapted to move toward the outlet end of the cylinder in response to a pressure drop on the outlet side of the valve member and force liquid out through the cylinder outlet, said valve member, upon moving to the outlet end of the cylinder, being engageable with said valve seat to cut oil flow from said outlet end of the cylindena delivery valve having first and second ports and an outlet, a connection between.

the cylinder outlet and said first port, a bypass connection between the cylinder inlet and said second port,said delivery valve having valve means movable between a delivery position wherein the second port is blocked and said first port is connected to the delivery valve 'out let to effect a pressure drop in the cylinder on the out-. let side of said valve member whereupon the valve member moves toward the outlet end of the cylinder to force a measured dose of' liquid through the cylinder .out let, the connection between the cylinder inlet and the delivery valve outlet, and a bypass position wherein said delivery valve outlet is closed and said ports are in communication with one another to provide for equalization of pressure on both sides of said valve member after the latter has moved into engagement with said valve seat, whereupon the valve member moves to the inlet end of the cylinder.

13. Apparatus as set forth in claim 12 including a spring biasing said valve member in said cylinder toward the inlet end of the cylinder.

14. Apparatus as set forth in claim 12 wherein said cylinder has an upper end and a lower end, the weight of the volume of the liquid in the cylinder displaced by the valve member therein being such in relation to the weight of the valve member that the valve member tends to move toward the inlet end of the cylinder.

15. Apparatus as set forth in claim 12 further comprising means extending into said cylinder from its inlet and engageable by said valve member for determining a retracted position of said valve member and axially adjustable relative to the cylinder for varying the stroke of said valve member.

16. Apparatus as set forth in claim 12 wherein said delivery valve means comprises a first delivery valve member biased toward a first position wherein communication is blocked between said first port and said delivery valve outlet and mechanically movable to a second position wherein communication is established between said first port and said delivery valve outlet, and a second delivery valve member adapted to be biased by the pressure of the liquid in said by-pass hose toward an open position wherein communication is established between said ports and adapted to be held by said first delivery valve member in a closed position wherein communication is blocked between said ports when [the first delivery valve member is in its second position.

17. Apparatus as set forth in claim 16 including a spring biasing said valve member in said cylinder toward the inlet end of the cylinder.

18. Apparatus as set forth in claim 16 wherein said cylinder has an upper end and a lower end, the weight of the volume of the liquid in the cylinder displaced by the valve member therein being such in relation to the weight of the valve member that the valve member tends to move toward the inlet end of the cylinder.

References Cited by the Examiner UNITED STATES PATENTS 2,705,094 3/1955 Howell 222-335 2,755,979 7/ 1956 Lawson et a1 222250 X 2,814,422 11/ 1957 Mercier 222-335 3,095,125 6/1963 Bundy 222-335 LOUIS J. DEMBO, Primary Examiner.

HADDS S. LANE, Examiner.

Claims (1)

1. APPARATUS FOR DISPENSING MEASURED CHARGES OF A LIQUID, COMPRISING A MEASURING CYLINDER HAVING AN INLET AT ONE END AND AN OUTLET AT ITS OTHER END, A LINE CONNECTED TO THE CYLINDER INLET FOR SUPPLYING LIQUID UNDER PRESSURE TO THE CYLINDER, SAID CYLINDER HAVING A VALVE MEMBER MOVOUTLET END, A RELATIVELY LOOSELY FITTING VALVE MEMBER MOVABLE IN SAID CYLINDER, SAID VALVE MEMBER BEING ADAPTED TO MOVE TOWARD THE INLET END OF THE CYLINDER ON EQUALIZATION OF PRESSURE ON BOTH SIDES OF THE VALVE MEMBER AND TO MOVE TOWARD THE OUTLET END OF THE CYLINDER IN RESPONSE TO A PRESSURE DROP ON THE OUTLET SIDE OF THE VALVE MEMBER THEREBY TO FORCE A MEASURED CHARGE OF LIQUID THROUGH THE CYLINDER OUTLET, SAID VALVE MEMBER BEING ENGAGEABLE WITH THE VALVE SEAT AT THE OUTLET END OF THE CYLINDER SO AS TO CUT OFF FLOW FROM THE CYLINDER, A DELIVERY VALVE HAVING AN INLET PORT AND AN OUTLET PORT, A VALVE ELEMENT OPERATIVELY MOUNTED IN SAID DELIVERY VALVE FOR OPTIONALLY ESTABLISHING COMMUNICATION BETWEEN THE INLET AND OUTLET PORTS THEREOF, A CONDUIT INTERPOSED BETWEEN THE CYLINDER OUTLET AND THE INLET PORT OF THE DELIVERY VALVE, A BYPASS VALVE MEANS HAV-

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