US2171687A - Liquid dispensing apparatus - Google Patents

Description

Sept. 5,1939. w. H. DE LANCEY LIQUID DISPENSING APPARATUS Filed Feb. 24, 1938 2 Sheets-Sheet l fl In -u H INVENTOR pEZAA/Cs w- Q 77M ATTORNEYS sep1 939;" I j w. H. DE LANCEY 2,171,687

LIQUID DISPENS ING APPARATUS Filed Feb. 24, 1958 2 Sheets-Sheet 2 INVENTOR v BIYMSREEN 1'71 pa l/M65) ATTORNEYS Patented Sept. 5, 1939 UNITED STATES PATENT OFFICE LIQUID DISPENSING APPARATUS sachusetts Application February 24, 1938, Serial No. 192,236

8 Claims.

This invention relates to an improved dispensing apparatus which is especially useful at gasoline filling stations. The whole apparatus is sometimes referred to as a gasoline pump but dispensing apparatus generally comprise in addition to the pump element other devices, for example in present-day apparatus, an air separator, a meter, .a visible indicator, a flexible hose, a dispensing nozzle at the end of the hose, and other details. In my Patent No. 1,870,900, dated August 9, 1932, I have shown an apparatus having an expansion chamber connected to the suction side of the pump.

According to one feature of the present improvements I provide an expansion chamber on the suction side of the pump and an air separator on the discharge side of the pump. These devices are arranged for a particular mode of operation in the apparatus which will be disclosed in connection with the accompanying drawings.

Fig. 1 is a diagrammatic layout of the elements in the apparatus and one indicating generally their relative vertical positions, all for easier observation than can be had in an assembled commercial form; and

Fig. 2 is a side view of a dispensing pump apparatus assembled in a commercial form of stand such as mounted outdoors at filling stations.

In the apparatus arrangement of Fig. 1, the expansion chamber 1 and the air separator chamber l2 are put in the apparatus at the same level but on opposite sides of the pump 4. Each chamber has a vent from the top to the atmosphere. Vent 8 of chamber I may be open to the chamber, but vent 20 of chamber I2 is automatically valve controlled at the chamber by float l9 so as to be open or closed according to conditions. The bottom inlet 9 to chamber 1 is also automatically valve controlled by float I so asto be open or closed according to conditions.

Afew examples under different conditions will disclose the principles of operation. When the underground storage tank I is suppliedwith gasoline and the apparatus is otherwise empty and pump 4 is operated by an electric motor, the operation will be as follows. The pump will start to suck gasoline through check valve 5 which permits up but not down flow. Air in the pipes 2 and 3 will be discharged through the pump into chamber l2 until the liquid which follows the air is discharged into chamber 12. During this operation bottom opening 9 of chamber 1 is kept closed by the weight of float valve Ill. But the top opening I! of chamber I2 is kept open by the weight of valve I8 and its float l9. Consequent- 1y air does not enter from the vent 8 of chamber 1 on the suction side but air does leave through the vent 20 of chamber l2' on the discharge side of the pump. The small chamber 30 at bottom of vent 20 has a float 3| with a valve 32 to give an 6 emergency closure for vent 20 when and if liquid passes through opening I! by leaking past valve l8. This is only an emergency provision. The secondary valve 32 in the separator is normally inert and does not close vent 20 in the usual 10 working of the apparatus. The primary valve l8 of the separator chamber l2 as stated is in position to ,keep vent 20 open. It stays open until the air of chamber [2 is displaced by liquid and the liquid level rises high enough, whichis preferably close to the top as indicated, to lift float l9 and thus cause valve l8 to close the small opening I! to vent 20. Thus, a lot of air in the system gets out of vent as the liquid is first pumped to fill the apparatus. The liquid is thus 20 pumped to substantially fill chamber I2 and the liquid must leave from the bottom of this chamber and proceed by the pipe connections indicated to fill the meter l5, visible flow indicator 23, flexible hose 24, until it leaves the apparatus through dispensing valve 25. The latter may be held open by handle 26, against its spring closing f means, and until the whole system is primed an full of liquid as intended.

After the above priming operation the apparatus is ready for the usual dispensing operations. In each of these it is desired to provide for the passage of liquid through the meter without enough air in the liquid to affect the quantity measurement. The air separator is for this purpose but the air separator construction and arrangement in the apparatus also have other purposes.

It will be appreciated that during the whole life of the gasoline pump apparatus thereare an enormous number of separate starting and stopping operations. An average delivery of the pump may require for example a steady pumping operation of about one and one-half minutes. When the delivery is running at full capacity 'a. modem pump will deliver about five gallons in twenty seconds. But the motor is turned on to run the pump before full delivery begins; it continues to run when there are momentary interruptions in the delivery; and the motor runs a little while after delivery ends and before the hose is hung up and the motor shut off.

The improved features of construction of expansion chamber and air separator chamber and their cooperative functions in the apparatus have pump (known forms of pump when idle permit a sufficient back flow for my purpose) and to the lowpressure side. The liquid cannot drain back to the storage tank I, being stopped by check valve 5. But it'can by my arrangement force its way ,past the bottom closure of expansion chamber I. It can enter that chamber and lift float I0 to keep inlet 9 free. Consequently the liquid levels off in chambers I and I2. The level in chamber I2 will be much lower now than it can be when the pump is operating. The vent 20 at the top of chamber I2 will now be open, as

} well as vent 8 of chamber I. The pump 4 is at the bottom, with connections to two upstanding legs, one on the suction and one on the discharge side, with equal liquid levels to balance the pressure on the two sides of the pump and both bodies of liquid in the upstanding legs vented to the atmosphere. Now, when the motor again starts the pump, the initial work to be done is very small. There is already a positive head on the pump inlet equal to that on the outlet side. The pump starts work from this balanced condition to progressively raise the level in chamber I2. This level rises against atmospheric pressure, there being no possibility of air or liquid pressure other than due to gravity in chamber I2 until the float I9 is lifted to close vent opening N. Then the system on the discharge side is substantially full and substantial pressure builds up. But before the pressure resisting the pump can start to build up beyond the diiference of level between low pressure leg ;(2' and chamber 1) and the high pressure leg (II and chamber I2) which at the start is zero, the pump has had time to get going under ideal starting conditions. And this permits the use of a motor with a very low starting torque.

There'are other advantages in the leveling off of liquid levels in chambers I and I2 during the idle periods of the apparatus. The liquid on the discharge side of the pump is at about fifteen pounds pressure when the pump is stopped in the ordinarycase. My arrangement provides for a back pressure flow to relief at atmosphericpressure. The float I9 needs very little back fiow of liquid through the pump to fall, and establish atmospheric pressure on the discharge side of the pump. This is an advantage. The arrangement invites and establishes a condition of equilibrium without air under plus or minus pressure on any part of the liquid during the rest period. It might seem that chamber I2 being below the highest point of the full system'would drain that which is shown slightly higher,.as the sight indicator 23 is. But with valve 25 closed, there need be no substantial drainage, and I have provided check valve 50 to insure against drainage, except to relieve excessive pressure. I prefer to locate chamber I2 close to the pump level and some of the other parts are conveniently higher in the pump stand.

When pumping starts after the liquid has been leveled off in chambers I and I2, the construction indicated will close valve 9 when the liquid is a little below one-third of float I0. Thus, while I is empty when the apparatus first starts, it contains some liquid after the first leveling off operation.

The operation for separating air from gasoline in tank I2 will be readily understood by those skilled in the art. During the pumping operation liquid enters from the bottom on'the left of screen I3. The general flow is to the top and down at the right of I3 and through cylindrical screen I6 and out at the bottom to pipe I4 and meter I5. Air, if it is in the gasoline, will under these conditions separate and collect at the top of the chamber. When enough is collected to displace liquid sufficiently to lower float I9, valve I8 is opened and the air pops out opening II. The liquid level rises quickly and lifts fioat I9 to close opening I1 and liquid does not leave through 11. It is important to see that liquid does not get through opening I'I. So I prefer to make float I9 of cork which will avoid losing the floating function. If valve I8 springs a leak, the time it can leak is small on account of the small time operation of the pump. And I have provided as before described chamber 30 and emergency float 3| of cork, valve 32, and the small opening indicated to vent pipe 20. It is usual to carry such vent pipes as 20 and 8 (and 6 for the storage tank) to an outlet point as high as the very top of the apparatus. It will be seen that by increasing the diameter of vent 20 I can provide an additional safeguard, beyond these already described, against squirting gasoline through the vent 29 to the atmosphere from the high pressure side of the pump. The small leakage that may occur through the bottom closures for vent 20 is.

not enough to get out at the top of 20. And as soon as the pump stops, any leakage will have a free drain back to the chamber I2 when float I9 lowers upon stopping the pump, as the float always will lower. I have deliberately provided for a very much larger air volume in chamber I2 when the pump is idle as compared to when it is running. The idea is to have the chamber I2 full when the .pump is working, except for that amount of air space necessary for the air separating function of the chamber. In fact if no air needs to be separated because the gasoline is already free of air, chamber I2 may be absolutely full. are under pressure for the gasoline to absorb the air. So under some conditions when no air is being separated, no air will be in chamber I2. But as soon as the pump stops, a large volume of air is taken in through the vent20.

I believe the arrangement for air separation will avoid loss of highly volatile constituents from the gasoline because they vaporize less when kept under pressure and except for momentary venting operations tending to lower pressure, there is pressure in chamber I2 acting to hold such constituents from vaporizing while the pump is operating. The venting operations during pumping will by my arrangement never release the whole body of liquid in chamber I2 to atmospheric pressure and the chamber I2 has only one liquidoutlet, that to the meter I5. I point out that screen I6 is of a known character of screen to assist in separating air and screen I3 may be of the same kind.

In the normal operation of releasing the air from chamber I2 during pumping I wish to emphasize the following operation and function attained by the constitution of the apparatus.

There is a tendency when gasoline and air Valve I8 does not close until liquid nearly fills 7s the chamber. This is a condition during pumping and there can be very little air space in the chamber during pumping. The pumping pressure compresses any air in the space after valve l8 closes, so there is only a thin layer under pres-. sure, the liquid level quickly rising above that required to close valve l8 at the start. Then as air is separated, it is under pressure. Its volume increases while its pressure is substantially constant in acting to displace the liquid level and drop float l9 enough to open valve l8 for an air release operation. When valve I8 is opened, the small volume of air being under pressure will make the air release a very rapid step. That is to say it pops out, lowers the air pressure of a small volume of air at the top very rapidly, and this gives the very large volume of liquid a quick up movement, tending to equalize the pressure, but up movement of the liquid closes valve l8 and the cycle starts over again. The result is that valve 18 is opened only momentarily, and the condition in chamber I2 is almost as if it were never opened as far as the pressure in the large body of liquid is concerned, and this gives a desirable efiect. t

A prior art example of an air separator chamber on the discharge side of the pump is found in patents to Mulligan, Nos. 1,119,979 and 1,119,980 of December 8, 1914. I believe my air separator per se as well as its combination with the other elements of the apparatus is a definite and highly useful improvement over such specified prior art disclosures and, within its field as herein disclosed, an improvement over any others of which I, am aware.

It will be appreciated that my arrangement of apparatus lends itself to the following desired operations when the pump is idle under heat conditions which expand the gasoline. As now known, it is desirable to keep the system generally full of liquid from storage tank I all the way to remote dispensing valve 25, and to permit enough back pressure flow through all devices (valve 50 is of a known kind of check valve that will permit back flow when the pressure on the high side exceeds a certain amount-about fifteen pounds in the desired case) in the line to avoid expanding gasoline causing leaks or bursting any part of the apparatus. And expansion tanks are known to take the swollen or expanded volume. In my arrangement there is a very quick relief for expanded volume of gasoline by heat. Both suction and discharge sides are constantly vented to the atmospheric pressure during idle periods. And by substantially increasing the air volume in the chamber 12 in each such period, such chamber is converted to a volume expansion chamber for such periods. Thus, there is one on each side of the pump and without any necessary by-pass pipes or valves for the relief of both sides. The pump used may be of the kind indicated in my prior patent. In such a pump if pressure on the discharge side tends to get higher than desired during the pump operation there is a pressure opening by-pass valve to lead enough gasoline back to the suction side to relieve the pressure.

Now that the principles of operations under difierent conditions and the diagrammatic laythe pump as well as chambers and i2. Vents 8 and 20 preferably go to the top of the pump stand 35. The pump motor, not shown in Fig. 1, is indicated at M in Fig. 2. The meter l5 is,below chambers 1 and I2 and has a shaft 36 to operate the register R. It will be understood that valve 25 during idle periods is hung up on a stand hook as indicated, and that the operating circuits and usual switch controls, such as rod H, for operating a dispensing apparatus are all implied from what is known, and without detail description.

I point out the various features of my invention and claim them as follows:

1. In a liquid dispensing apparatus, a pump having a suction pipe for drawing liquid from below the pump level, a delivery conduit, a normally closed valve controlling the outlet of said conduit, an expansion chamber connected at the bottom to the suction side of the pump, a second chamber connected at the bottom to the discharge side of the pump, both of said chambers having storage capacity located at the same level which is at or above the pump level, a vent to the atof a kind to permit back pressure flow through it when idle, and connected to the pump, an

electric motor of sufficiently low starting torque to-take advantage of a-leveling off or back flow of stored liquid in the apparatus from the second chamber 0n the discharge side to the expansion chamber on the suction side of the pump during idle periods of the pump when the liquid pressure is balanced with an equal head of liquid on both sides of the pump preparatory to easy starting conditions for the pump.

2. The construction of the foregoing claim in which the automatic valve for the vent opening at the top of the chamber on the discharge side of the pump is controlled by a float so as to open the vent whenever enough air is separated from liquid during operation of the pump to lower the liquid level in that chamber and thus lower the float'for opening the said valve.

3. In a liquid dispensing apparatus a pump which permits back flow when idle and having a. suction line and a discharge line in the form of legs, extending above the pump, each leg having a substantial storage capacity with a vent to the atmosphere at the top and the whole discharge line located so that it is capable of draining toward the pump, a float controlled valve in each leg, one to close the vent on the discharge leg by rising liquid level in that leg, and one to open the storage space in the suction leg upon rising liquid and to close it on falling liquid level in that leg, the former of the two valves being located at the top and the latter at the bottom of the storage spaces in said legs, whereby when the pump stops the liquid level levels ofi in the two legs for substantial liquid. storage on both sides of the pump at the same level for easy pump starting, and in addition a suction line connected to and extending below the leg on the suction side of the pump to withdraw liquid from a low level storage tank having means to prevent a drain-back to the latter tank.

the upper part of the suction pipe, avented 4. In a dispensing apparatus a low level storage tank, a suction pipe extending up from the tank, a check valve in the pipe to prevent back flow to the tank, a pump connected to the upper part of the suction pipe, an expansion chamber above the pump and having its bottom part connected by a branch to the suction pipe between the pump and check valve, a vent from the top of the expansion chamber, a gravity valve in the chamber at the bottom including a, float to shut ofi connection between the expansion chamber and suction pipe except upon suflicient back pressure flow in the suction pipe to lift said valve, the float of said valve holding it open when more than a predetermined amount of liquid is in the expansion chamber, a discharge pipe connected to the pump, an air separator chamber, connected near its lower end to the discharge line and at the level of the expansion chamber, a vent at the top of the air separator, a float controlled air release valve for such vent, all constructed and arranged on the high speed operation of the pump to maintain said expansion chamber at least partially empty and to maintain liquid under pump pressure in the air separator chamber, but in idle periods of the pumpto maintain the same liquid level in the two chambers on opposite sides of the pump with both vented tothe atmosphere.

5. In a dispensing apparatus for the purpose described a low level tank, a suction pipe extending up from the tank, a check valve in the pipe to prevent back flow to the tank, a pump connected-to the upper part of the suction pipe, :anexpansion chamber above the. pump and having its bottom part connected by a branch to the suction pipe between the pump and check valve, a vent from the top of the expansion chamber, a gravity valve'in the chamber at the bottom including a fioat to shut off connection between the expansion chamber and suction pipe except .upon sufficient back pressure flow in the suction pipe to lift .said valve, the float of said valve holding it open when liquid is in the expansion chamber, a second chamber connected to receive liquid from the discharge side of the pump and also .to empty into said side and positioned high enough above the pump to insure a drain-back through the pump to maintain liquid in the expansion chamber between periods of pump operation, and a valve controlled vent at the top of said second chamber automatically operable to open as the drain-back to the expansion chamber starts.

6. A dispensing apparatus comprising a low level storage tank, a suction pipe extending up from the tank, a check valvein the pipe to prevent back flow to the tank, a pump connected to expansion chamber above the pump and having its bottom part connected to a branch of the suction pipe between the pump and check valve, a float controlled gravity valve in the chamber for the bottom connection, a discharge pipe extending from the pump, an air separator chamber, a meter, a flexible hose, and a spring closed dispensing-valve at the end of the hose all arranged along the discharge pipe in the order named, a vent in the top of the air separator chamber, said chamber being at the same level as the expansion chamber, a float valve arranged to open said vent by the weight of the valve and close it by the lifting of chambered liquid on the float, the whole apparatus between said check valve and a point in the system beyond the liquid outlet of the air separator being arranged to permit an equalizing pressure action between such valves which will cause liquid storage at atmospheric pressure at equal levels in both chambers to admit downward liquid flow'out of said tank into said pipe and to stop of! air flow between the vented upper tank and said pipe when the pump is operating, a delivery line connected to the discharge side of the pump, an automatic closing valve at the end of said line, and a pressure tank in said delivery line at substantially the same level as the upper one of said two storage 'tanks, the pressure tank having a vent opening and a float valve therefor at the upper part, all constructed and arranged for the pressure tank to drain back through the pump to the upper storage tank until their liquid levels are equal when the pump is idle'and for the pump when it starts to operate to first take liquid from the upper storage tank, raise the level in the pressure tank and close its vent and proceed with pumping operations from the supply in the lower storage tank.

8. The structure of the foregoing claim in com binatlon with means in the pressure tank to separate air for intermittently displacing the liquid level in such tank sufficiently to operate the float valve for air release.

WARREN H. DE LANCEY.

Images