US2018119A - By-pass valve for liquid dispensers - Google Patents

Description

Oct.22, 1935. w. H. D. BROUSEQ 2,018,119

BY-PASS VALVE FOR LIQUID DISPENSERS Filed Nov. 22, 1935 I "Mentor: VWl/iamllflBrouse.

Patented a. 22, 1935 UNlTED :STATE BY-rAss'vALvE FOR LIQUID msrsnssps William H. D. Brouse, Toronto, Ontario, Canada,

assignor to- Service Station Equipment Compally-Limited, Toronto, Ontario, Canada Application November 22, 1933, Serial 'N... 699,149

9 Claims- (01. 103-42) The principal objects of this invention are, to eiIect a saving in the installation of liquid dispensing pumps by providing a device which will require less power to operate the pump by the elimination of back pressures when the discharge from the pump is closed. a

The principal features of the invention consist in the provision of a by-pass valve in a circulatory portion of a liquid dispensing system whereby the flow of the liquid through the pipes is utilized to effect the positive closing of the bypass valve when the liquid is being dispensed and to efiect the positive opening of the valve to permit the unrestricted flow oi liquid through the by-pass with'the consequent relief of stress on the pumping unit when the discharge is closed.

In the accompanying drawing, Figure l is a diagram illustrating the piping arrangement of a liquid dispensing unit equipped with my improved by-pass device.

Figure 2 is an enlarged longitudinal mid-sectional view through the by-pass valve.

Figure 3 is an enlarged longitudinal mid-sectional view of one of the inspirator nozzles used in co-operation with the by-pass valve.

In the dispensing of liquids and particularly that of gasoline, the direct discharge type of pump is being extensively used, that is, the type wherein the liquid is drawn from a supply tank by a suitable pump and is discharged through a meter to the dispensing nozzle.

Ordinarily upon the closing 01' the dispensing nozzle the full pressure of the pump is exerted against a by-pass valve which is normally spring loaded to resist the 'Iull head pressure of discharge and the motor is required to lift such valve against such resistance until the operation of the pump is arrested. The shock'pf this sudden back pressure is extremely severe upon the motor operating the pump and consequently requires a very heavy unit. I

In the arrangement herein shown a by-pass valve is provided, the body I of which is formed with an inlet 2 and an outlet 3 between which is arranged a passage 4 closed by a valve 5.

The valve 5 is provided with a hollow cylindrical portion 6 which extends upwardly into a cylindrical cavity 1 formed in a plug 8 threaded into the top end of the valve.

A coil compression spring 9 is arranged within the hollow extension 6 to hold the valve down wardly to its seat.

The pressure of the spring 9 may be regulated by an adjustable block it threaded in the upper.

; threaded end oi the cavity 1 in the plug 8,

The upper end of the cavity 1 is closed by a cap screw i I.

A stem I2 is secured centrally inthe lower end of the valve 5 and extends through a central circular opening i3 in a partition wall I4 s arranged in the valve body below the inlet 2, s and slidably mounted upon the lower reduced end l5 of said stem is a piston member I 6 provided with a sleeve II, the upper end of which abuts the shoulder I 8 at the upper end of the 10 reduced portion of the stem.-

The piston it operates within a cylindrical cavity is arranged below the partition i4 and when the valve 5 is closed, said piston is held with its sleeve i'l engaging the shoulder It by a light coil compression spring encircling the spindle below the piston and engaging a washer 2i secured in-an adjustable position by a nut 22 threaded on the spindle.

An opening 23 is provided in the wall of the 2 cylindrical cavity is communicating with the inner end thereof above the piston Hi, the outer end of which is threaded to receive a pipe 2% and an opening 25 is connected with the lower end of the cylinder and communicates with the pipe 5 26. y

The valve is operated under the influence of changes of pressure due to the application or a suction effected through either of the pipes 243 or 26. When suction is applied to the pipe 24 the piston I6 is caused to move, upwardly lifting the valve 6 from its seat against thepressure oi the spring '9 and a free flow of liquid from the inlet 2 to the outlet 8 oi the by-pass valve 5 is provided. 5

When suction is applied to the cylindrical cav ity below the piston it through the pipe 26 and its communicating opening the valve 5 is drawn downwardly against the pressure oi the liquidflow between the inlet and outlet and against w the pressure of the bottom spring 20, so that the flow through the by-pass is arrested. 1

In order to accomplish this manipulation of the valve it is oi course necessary to provide suit== able suction. means whichare incidental to the flow of liquid through the system.

In the arrangement vherein shown the liquid supply tank 2? is connected by a pipe 28 to the pump as which is oi. any suitable design and motor operated. so

The discharge pipe 30 from the pump leads to a suitable metering device 3| and from thence the fluid is directed through a flexible hose and control nozzle 82.

Intermediate oi the length of the pipe 30 i pro- 5% vide a venturi tube 33 which has a short restricted passage 34 at the inlet and leading to an elongated divergent passage 35 and anpopening 33 arranged at the throat is connected by the pipe 26 to the lower end of the by-pass cylinder.

A branch pipe 31 isconnected to the pipe 33 between the pump 23 and the Venturi pipe or tube 33 and leads to the inlet opening 2 of the by-pass valve. Within this branch pipe is arranged a Venturi tube 38 similar-to the venturi tube 33 and the throat thereof is connected by the pipe 21 to the upper opening of the cylinder of the by-pass valve.

A branch pipe 39 connects the outlet 3 of the by-pass valve with the supply pipe 23 leading from lifted from its seat and a circulatory flow is commenced in the looped pipe structure containing the by-pass valve. The moment that the flow of liquid commences a suction is established in the Venturi tube 33 which is conducted through the pipe 24 to the upper end of the cylinder cavity IQ of the by-pass valve and pulls upwardly on the piston l6 overcoming the resistance of the valve spring and holding the valve open so that the liquid flows freely through the by-pass valve and return branch 39 to the tank.

It will be understood that the application of suction from the Venturi tube 33 to the upper side of the piston it causes the sleeve I'I thereof topositive pressure influence on the underside of the piston it which will greatly assist in the initial opening of the by-pass valve 3. The load upon the pump is thus relieved practically instantaneously and the combined suction on the piston and the pressure of the liquid against the underside of the valve and piston lift the valve against the pressm'e of the spring 3 which may be adjusted in the manner described.

Immediately upon the opening of the discharge nozzle 32 pressure in the pipe 31 is immediately relieved and suction through the pipe 24 is discontinued while concurrently the ilow of liquid through the venturi tube 33 creates a suction through the pipe 23 which communicates with the lower end of the cylinder cavity and draws downwardly upon the piston against the spring 23 for a certain distance before the pressure exerted is sufficient to eil'ect the closing of the valve 5 against the pump pressure. This cushioning of the valve will prevent hammering and will ensure be understood that the valve may be spring loaded to resist the pressure of the discharge flow and a single venturi used to hold the valve open to relieve the motor of back pressure when the discharge is closed.

What I claim as my invention is:

1. In a liquid dispensing equipment having a motor operated pump and a by-pass for connecting the discharge and intake of the pump, and a spring-closed valve in said by-pass directly acted upon by the pressure of the pumped liquid to open the valve against the closing pressure of the-spring and thereby permit the flow of liquid through the by-pass from the pump discharge back to the pump intake, the combination therewith of pressure responsive means co-operatively associated with the valve, and means co-operating with the flow of liquidthrough said by-pass and connected with said pressure responsive means to impart an operating pressure influence thereto and eilective only after said valve has opened for assisting the opening movement of said valve.v v 1 2. In a liquid dispensing equipment having a motor operated pump and a by-pass connecting the discharge and intake of the pump, and a valve arranged in said by-pass to permit the flow of liquid from the pump discharge back to the intake, the combination therewith of suction creating means incorporated in the discharge from the pump, and displaceable means having a cushioned operative connection with said valve and displaced by said suction means for influencing said valve in accordance with the flow of liquid through the discharge.

3. In a liquid dispensing equipment having a motor operated pump and a by-pass connecting the discharge and intake of the pump and a valve arranged in said by-pass to permit the flowof liquid from the pump discharge back to the intake, the combination therewith of a cylinder associated with the casing of said valve having an opening therein, a spindle extending fromthe valve axially of said cylinder, a piston operating in said cylinder and slidably associated with said spindle, a suction creating device arranged in the discharge from the pump, a pipe leading from said suction creating device to, the opening in said cylinder to effect the axial shifting of said piston through the flow of liquid through said suction creating device, stop means for limiting the sliding movement of the piston on the spindle in one direction, and resilient cushioning means resiliently opposing the sliding of the piston on the spindle in the reverse direction.

4. In a liquid dispensing equipment havinga motor operated pump and a by-pass connecting the discharge and intake of the pump and a valve arranged in said by-pass to permit the flow of liquid from the pump discharge .back to the-intake, the combination therewith of a cylinder associated with the casing of said valve having openings at the top and bottom, a piston operating in said cylinder connected with the valve, a suction creating device arranged in the by-pass between the pump and the valve intake, a pipe connecting said suction device with one of the openings in said cylinder to effect the lifting of the valve, a suction creating device arranged in the disc e from the pump beyond the by-pass connection, and a pipe leading from the latter suction creating device to the other opening in said cylinder to urge the valve closed through the new of liquid through the latter suction creating device.

supply and a dispensing discharge and a. by-pass connecting the discharge side of the pump with its intake, of a Venturi tube arranged in the by-pass, a valve arranged in said by-pass between said venturi and the pump intake, a piston operatively connected with the bypass valve, a cylinder enclosing said piston, a pipe leading from the throat of said venturi and connected with said cylinder at one side of said piston, and suction creating means arranged in the pump discharge and connected with said cylinder on the other side of said piston and creating a suction in the cylinder on the said other side of said piston in accordance with the flow oi liquid through the dispensing discharge.

6. In a liquid dispensing apparatus, the combination with a pump connected with the liquid supply and a dispensing discharge and a by-pass connecting the discharge side of the pump with its intake, of a venturi tube arranged in the discharge between the pump and the dispensing end, a Venturi tube arranged in the by-pass, a by-pass valve arranged in said by-pass between the latter venturi and the pump intake, a piston operatively connected with the by-pass valve, a cylinder enclosing said piston, a pipe leading from the throat of one of said venturi tubes and connected with said cylinder at one side of said piston, and a pipe leading from the throat of the other oi said Venturi tubes and connected with said cylinder at the other side of said piston.

7. In a liquid dispensing apparatus, a pump connected witha liquid supply and having a controlled discharge, a venturi arranged in said controlled discharge, a by-pass arranged between said pump and said venturi and connected to the pump intake and having a venturi therein, a valve casing arranged in said by-pass between the venturi therein and the pump intake, a spring loaded valve in said valve casing closing the passage therethrough, a cylinder arranged in said valve casing in alignment with said valve, a spindle extending from said valve into said cylinder, a piston slidably'mounted on said spindle and operating in said cylinder, a cushioning spring mounted on said spindle and engaging the outward side of said piston, a pipe 5 connected with the lower end of said cylinder and leading to the throat of the venturi in the pump discharge, and a pipe connected with the upper end of said cylinder and. leading to the throat of the venturi in the by-pass. 1o

8. In a liquid dispensing equipment the combination of a motor driven pump, a dispensing conduit connected with the pump discharge and periodically opened to release the pumped liquid therefrom and thereafter closed to cut oil Iur- 15 ther flow therefrom, a by-pass conduit extending between the pump discharge and intake, a valve controlling the flow of liquid through the by-pass and automatically closed during the release of fluid from said discharge, and means an automatically controlling said by-pass valve in accordance with the difference in velocity flow of liquid in said dispensing conduit and by-pass.

9. In a liquid dispensing equipment the combination of a motor driven pump, a dispensing conduit connected with the pump discharge and periodically opened to release the pumped liquid therefrom and thereafter closed to cut off turther flow therefrom, a by-pass conduit extending between the pump discharge and intake, a valve in said by-pass spring held closed against the dispensing pressure of said pump only when said. dispensing conduit is open to discharge the pumped liquid and adapted to be forced open by the pumped liquid against the spring pressure immediately on the closing of the dispensing discharge to by-pass the undispensed liquid, and means imparting respectively opening and closing influences to said by-pass valve in acpassed or dispensed liquid.

' H. D. BROUSE.

Images