US 2549620 A
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PUMPING MECHANISM Filed May 28, 1945 /n/l/ENTOR:
Patented Apr. 17, 1951 PUMPING MECHANISM Orville Mitchell, Dallas, Tex., assignor to John E. Mitchell Company, Dallas, Tex., a corporation of Missouri Application May 2s, 1945, serian No. 596,307
The present invention relates to 'a pumping mechanism. More particularly, it relates to a liquid piston pumping mechanism anda system in which it is used. Y
It is an object of the inventionto provide a liquid cylinder pumping system having multiple cylinders, one operating for pumping purposes while the other is on a suction stroke.
It is a particular object of the invention to Y provide a liquid piston pump having multiple pistons, one of which is on the compression stroke while the vother is on the suction stroke, and both of which use the same body of liquid which is, under control, transferred from one cylinder to the other and back again. Hence, it is a further object of the invention to provide the control aforesaid for the transfer of the liquid forming the piston from one cylinder to the other, and, at the same time, to transfer control of the compression drum from one cylinder tothe other.
' It is a further object to provide the foregoing pumping system under control of a single motive means.
It is a further object to provide theA foregoing with a single motor operating in a single direction, or with a reversible motor, as is desired.
It is a' further object of the invention to provide a pump having very high volumetric erliciency, particularly through the elimination or reduction of waste space between the piston means and the exhaust valve. A further object is to provide increased valve efficiency, particularly by the reduction in the frequency of operation required of the controlvvalves.
A further object is to provide increased heat efficiency and low cost of installation and construction.
In the drawings:
Fig. l is an elevation',A partly in section, of a system as described;
' Fig. 2 is a wiring diagram of the same;
Fig. 3 is a fragmentary view showing the use of adiferent type of pump; and
Fig. 4 is a wiring diagram for use with the 3 Claims. (Cl. 230-91) automatic valve 20, such as a solenoid valve. Fromthe valve 20, another'line 2| leads to a. T 22. From -this T 22, a pipe 23 leads into the bottom of the so-called liquid cylinder, or containerII. From the T 22, there also leads a line 24 extending to another automatic solenoid valve 25, which is connected by a pipe 26 to a T 21. From the T 21, a line 28 is connected to the suction inlet of the pump IU. The foregoing forms one-half of the pipe network between the pump and the two liquid cylinders.
The connections for the liquid cylinder I2 are similar. From the T I8 connected with the pump outlet I1 another line 29 leads to a solenoid valve 30 that is connected by a pipe 3I to a T 32. From the T 32, a pipe 33 leads into the bottom of the liquid cylinder I2. Also, from the T 32, a pipe 34 leads to another automatic valve 35 that is connected by a pipe v36 with the inlet T 21.
A liquid supply 38, with a suitable valve, leads into the cylinder I I to insure an adequate supply of liquid at all times.
The outlet sides of thetwo liquid. cylinders II and I2 are likewise similar. The liquid cylinder II has an outlet pipe that connects into a T 4I. This T is connected with a suction line. To this end, it is connected directly to a suction check valve 42, into which an air supply line 43 leads. The other side of the T 4I is connected by a pipe 44 into a liquid chamber l45 of the control device I3. The chamber 45 is connected by a valve seat-containing port 46, with a cell 41 directly above the chamber 45. The chamber 41 has an outlet pipe 48 that leads to a check valve 49. The other side of the check valve is connected by a pipe directly into the air receiver I4.
The chamber 45 receives a combination float and valve member 5I that is supported on a stem 52 that passes through the port 46. The stem 52 is attached to a exible diaphragm 53 sealing ofi" the top of the cell 41. The top end of the stem 52 lis attached by a slot to one arm 54 of a bfurcated rocker arm member, generally designated at 55. This rocker arm is pivoted at 56 for its support.
The other liquid cylinder is connected byr a pipe 60 into a T 6I.. This T is in similar manner connected through a suction check valve 62 with an air line 63. The other end of the T 6I is connected by a pipe 64 with a second chamber 65 within the control I3. The chamber 65 is connected through a valve seat-containing port 66 with a cell 61 directly above the chamber 65,'
This cell is connected by a pipe 68 into a check Valve 99, from which a pipe 'I9 leads into the air receiver I4.
The chamber 65 receives a combination float and valve 'lI that is supported on a stem 'I2 that passes through the port 96. The stem is attached to a flexible diaphragm f3 that seals off the top of the cell 91. The top end of the stem 'I2 is attached by a slot to a second arm 'a' 4 of the rocker arm 55. The rocker arm 55 has a middle arm 'fl to which one end of an over-center, snap-action spring 'i8 is secured. Its other end is attached in line below the pivot 65, to the valve casing.
The rocker arm 55 also. operates a switch. To this end, the arm 54 carries avcontact lBI `that -is adapted to make with a xed contact 82. Likewise, the other arm l4 carries a contact 33 that is adapted to close with a Xed contact 84.
A typical wiring diagram is shown in Fig. 2, for use with a motor for a unidirectional pump, which will be assumed is in constant operation. Of course, it will be normally provided with a master switch control, or the like.
In Fig. 2, the power lines are shown at 86 and 81. The power line S5 is connected to the rocker arm 55, and thereby to the two contacts 8l and 83 thereof. Needless to say, the contacts are suitably insulated to prevent electrical grounding.
The contact 9i is adapted to close with the contact 82, which latter is connected by an electrical lead S8 to a terminal 89. The terminal 89 is connected by a line 99 to the coil of the valve 2U, the other kend of which is connected by a line 9| to a terminal 92. The terminal 92 is connected by a line 93 to a terminal 94.
The terminal 99 is also connected by a line 95 through the coil of the valve 35, from whence it is Aconnected by a line Si? to a terminal 91. The terminal 97 is connected by a line 98 to the terminal 94, which is connected to the other power line 81.
The contact 93 of the rocker arm 55 is adapted to close with a xed contact 84. This latter is connected by a line 99 to a terminal YIllil. The terminal Ill@ is connected by a line lill into the coil of the valve 99, from which it is connected by a coil |92 to the terminal 92.
Another line |94 leads from the terminal |90 into the coil of the valve 25, from which a line IE5 leads to the terminal 97.
In Fig. 3, a reversible motor is used operating a reversible pump. The reversible motor is shown at I I5 and is connected by a belt to the reversible pump I i6. This pump is connected by a line I I'I into the liquid cylinder II, and by a line VII8 into the cylinder I2. The connections for this compressor are shown in Fig. 4. The rocker arm 55, in this case, is actuated by the same control mechanism I3. However, the contact 82 is connected by a line 29 into the forward windings of the motor I I5, and the contact 84 is connected by a line I2I into the reverse windings of the motor. The lead 9'! is also connected as a common into the motor.
Operation An amount of operating liquid, such as water, is introduced through the inlet line 38 into the two liquid cylinders II and I2. The preferable amount will be somewhat more than enough to fill one of the two cylinders, as will appear.
In Fig. l, the motor for the pump I0 is operating to pump through the left cylinder II and to apply suction through the other cylinder I2. It
has almost finished its stroke. The motor of the pump I9 is operating. It will also be seen that the rocker arm 55 is in position to close the two contacts 9I and 82 and to maintain the contacts 93 and 94 open. Thus power is introduced from the power line S3 through the contact 82, the line 89, to the junction 89, from whence it divides, by the line 99 through the valve 20, the line 9i, the junction 92, the -line 93 and the junction 94 t-o the other power line 8l. At the division point 89, it also is connected through the line 95, the valve the junction 91, and the line 98, to the junction 94 and the other power line 81. By this means, the ftwo valves 20 and 35 are opened.
When these -two valves are opened, and the other two valves 39 and 25 are deenergized and hence closed, the suction line 2S of the pump I0 will be connected to the right hand liquid cylinder l2 through the pipe 33, the T 32, the pipe 34, the valve 35, the pipe 36 and the T 2l. The pipe 95E will be blocked off by the=closed valve 30 and the pipe 29 will beblockedfoif by the closed valve 25. The high pressure outlet line of the pump i9 will be connected by the pipe I1 to the T I8, and thence through the pipe I9 and the open valve 29, the pipe 2l, the T 22, and the pipe 23 into thepressure liquid cylinder I I. The closure of the valves 25 and 3U prevents backflo-w or parasitic flow through both the pressure and the suction lines.
The water will then be forced upwardly into the cylinder Il and suction -will -be applied t0 the cylinder I2 as 'the water is drawn therefrom. The, suction draws air inrfrom the Vinlet 93 through the check .valve 52 to the T 6I, Yand thence by the pipe into the cylinder I2. At this time, and in the position shown, the liquid cylinder I-I has been illed vand the water has been -forced out through the pipe 4 9 ,and the T 4I. The check valve 42 prevents passage of this water back into the air inlet line 43, so that it is forced out through the pipe 44 into the chamber 45 of the control I9.
After a relatively small additional quantity -of water, beyond that shown in Fig. 1, is forced into the chamber 45, it will floatthe oat 5I., which will be moved upwardly in the chamber. This upward movement -will rock the rocker arm 55 and will finally throw the spring I8 over center, which will lower the iloat 'II and `will quickly draw the oat 5I up into the Valve seat 45, sealing ilow therefrom. It is., of course, understood that the float 'II at the same time opens the valve seat 66.
. The upward movement .of the-liquid in the liquid cylinder II and -nally in the chamber I3 forces air above .the liquid column out past the ioat 5I, through the port 46 and out into the cell 4l, out the line 48, past the check valve 49, and by the pipe 59 into the receiver I4. This flow is obstructed when the rocker arm y55 shifts over as' aforesaid to close the float 5I into the seat 46 and to` open the iloat l! in the seat 93.
When the rocker arm 55 4thus shifts over center, closing the float valve 5I and opening the oat valve l l, it also shifts the circuits, as shown in Fig. 2. It opens the contacts 8i and 82, thereby breaking the circuits to the valve coils 2D Iand 35, so that these two valves close. At the same time, however, it closes ythe contacts 83 and 84,. When these two contacts are thus closed, the power from the line 8 6 flows through them and thence, by way of the line 99, to the junction |90. From the latter, it flows through the line IBI through the coil .ofthe valve 30, and by the Vline 5. |02 to the junction 92, thence by the line 93 to the junction 94 and the other power line 81. It also iiows from the previously mentioned junction through the line |04 to the coil of the valve 25, and thence by way of the line It to the ljunction 9T, and by the line 98 to the junction .94 in the other power line.
As a result of this shift of the rocker arm 55, the two valves 20 and 35 are released to closed position as aforesaid, but the two valves 30 and 25 are opened. This reverses the flow of the water although the pump continues to run in the same direction. The piunp inlet 28 is now connected to draw water from the liquid cylinder I I through the pipe 23, the T 22, the pipe 24, the open valve 25, and the pipe 26. The Vclosure of the valve 35 cuts the other liquid cylinder I2 from this suction line, and, of course, the parasitic suction line is cut off by the closure of the valve 20. The high pressure line I'I from the pump I!! is now connected -through the valve 3U andthe pipe 3| to the T 32 and the pipe 33, to dischargej water into the liquid cylinder I2. The closure of the valve 2B prevents the Vflow of this water into the cylinder II.
The foregoing disposition of the network thereby effects a withdrawal of the water from the cylinder I I and its pressure discharge into the liquid cylinder I2. As the level rises within the liquid cylinder I2, the air that was drawn in during the previous suction stroke is now forced up through the pipe 60, the T 6I, the pipe 64, the chamber 65, past the port 66, into the cell 51, and thence past the check valve 69 and into the receiver I4. Likewise, the lowering of the level of the water within the liquid cylinder II draws in additional air through the air line 43, past the check valve 42, and by the pipe 40 into the cylinder. At this time, the closure of the check valve 49 within the line 50 and the closure of the iioat valve I prevents suction of air from the receiver I4.
When the modification of Figs. 3 and 4 is used, with a reversible motor, it is not necessary to have the pipe network shown in Fig. 1. It is necessary only to have a line from the pump tol each of the two liquid cylinders II and I2, these two lines being shown at Ill and IIS in Fig. 3. The control I3 is the same as before. However, when the float is in the position shown in Figs. 1 and 4, closing the contacts 8| and 82, the power is introduced from the line 86 through the contacts 8I and 82, and by the line I2 to the forward winding of the motor II5, and thence to the other power line 81. This drives the motor in its forward direction and will pump the liquid into the cylinder II by way of the pipe II'I, at the same time drawing the liquid from the liquid cylinder I2 through the pipe I I8. When the control I3 shifts, it opens the contacts 8! and 82, deenergizing the forward windings of the motor I I5, and it closes the contacts 83 and 84 to energize the reverse winding of this motor. This latter circuit passes from the power line 86 through the contacts 83 and 84, the line I2 I, to the motor II5, and thence to the power line 8'I. This reversal changes the direction of the water fiow within the system, withdrawing water from the cylinder I I through the pipe I I'I, and discharging it under pressure through the pipe IIB into the liquid cylinder I2.
By the foregoing means, it will be seen that air is at all times being compressed into the receiver I4, from one or the other of the two liquid cylinders Il and I2. The liquid pump of this type has generated by the compression of the air may vflow into the water and be dissipated thereby. Great volumetric efciency can be obtained because the piston, being liquid, can flow right up against the valves, and no mechanical clearance is required at the end of the piston strokes to accommodate the valve operation. Where the average air compressor operates with a volumetric efficiency of about seventy percent, the present pump can attain as high as ninety-nine percent volumetric efiiciency. The latter, in the present system, is controlled by the ratio of the size of the liquid cylinder and the clearance between the water piston and the valve.
The frequency of operation of the valves in the liquid system here presented is very much less than that required of a mechanical type of pump. This fact, along with other factors that will be obvious, reduces the wear on the valves very substantially.
Furthermore, there is a great reduction in cost in the liquid pump system. All of the equipment used herein consists of a simple pump with plain tanks, simple valves, and ordinary piping, with a reversing control that is free of complications. It is inexpensive to operate and simple'to install.
What is claimed is:
1. In a gas compressing system of the liquid piston type, a pair of relatively large liquid containers, a pair of relatively small oat chambers, one connected with the top of each liquid container, a gas outlet from the top of each float chamber, the float chambers being thereby connected in series with their respective liquid cons tainers, valve means adjacent the float chambers permitting gas flow only outwardly from the chambers through the gas outlets, a unidirectional gas inflow conduit for admitting gas into each liquid container, a float device in each chamber, means to transfer a quantity of liquid alternately from one liquid container and its float chamber, to the other liquidcontainer and its float chamber, such liquid rising in each float chamber until it lifts the float device therein, means responsive to elevation of each float device to reverse the travel of the liquid, and cause it to be withdrawn from such float chamber and liquid container until it fills the otherliquid container and float chamber, there'being means to maintain the float device so elevated, in elevated position until the liquid rises in the other iioat chamber and elevates the other float device therein.
2. In a gas compressing system of the liquid piston type, a pair of relatively large liquid containers, a pair of relatively small float chambers, one connected with the top of each liquid container, a gas outlet from the top of each float chamber, the float chambers being thereby connected in series with their respective liquid containers, valve means permitting gas flow only outwardly from the chambers through the gas outlets, a unidirectional gas inflow conduit for admitting gas into each liquid container, a oat device in each chamber, means to vtransfer a quantity of liquid alternately from one liquid container and its float chamber, to the other liquid container and its loat chamber, such liquid rising in each float chamber until it lifts the float device therein, means responsive to elevation of each oat device to reverse the travel of the liquid, and cause it to be withdrawn from such oat chamber and liquid container until it lls the other liquid container and oat chamber,
there being means 4'to maintain the .iioat device so elevated, in elevated position .until the liquid rises'in the other iloat chamber and elevates the othertoatdevicetherein, the unidirectional gas inow conduits being connected into the system betweenthe maximum liquid level `in the float chambers, and the tops `of the liquid containers.
3. In a gas compressing system ofthe liquid piston type, a pair of relatively large liquid containers, a pair'of relativelysmall oat chambers, one.. connected with the top offe'ach .liquid container, Ya gas outlet `from the top of each float chamber, the float chambers being `thereby connected in Yseries with their respective liquid containers, valve means 'permitting gasfiovv only outwardly from the chambers through the gas outlets, a unidirectional gas inflow 'conduit for admittingpgas into .each liquid container, .a float device'in Yeach chamber, means to vtransfer a quantity 'of liquid alternately from `one liquid container and its oat chamber, to the Vother liquid container and its float chamber, such liquid rising in `each oat chamber until it lifts the .oat device therein, means responsive to elevation vof each iloat device to reverse the travel 8 of the liquidi-and 'causei itto be Withdraivnfrom such oat 4chamber-and liquidcontaineruntil-it llsithe other liquid lcontainer and float chamber, there ,being .means to maintain the oat device so elevated, in elevated positionA until theliqu'id rises in the other iioat chamber and .elevates the other oat device therein, each iloat device having Ya valve portion, anda valve seat in the outlet from- `each float'chamber, that is closed `:by said valve portion Whentheifioat .is elevated "as aforesaid.
, REFERENCES CITED The -followingreferences are of record in the ile of this patent:
YUNITED vS'IA'I'ES PATENTS Number Name Date 261,560 .Mayrhofer July 25, 1882 402,517 Fitzpatrick .Ap1'. 30, 1889 6945885 OConnell Mar. 4, 1902 1,766,998 Jacocks June 24,1930 41,902,961 La Bour Mar. 28,1933