US2671402A - Rotary pump - Google Patents

Description

C. L. PELHAM ROTARY PUMP March 9, 1954 5 Sheets-Sheet 1 Filed April 5, 1948 1 53 INVENTOR.

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Filed April 5, 1948 March 9, 1954 Q L, PELHAM 2,671,402

ROTARY PUMP 5 Sheets-Sheet I5 "I ll/1%.

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INVENTOR.

a? ATTU RN EYS March 9, 1954 c. L. PELHAM ROTARY PUMP Filed April 5. 1948 5 Sheets-Sheet 4 a I I ATTEI RN EYS C. L. PELHAM ROTARY PUMP March 9, 1954 5 Sheets-Sheet 5 Filed April 5, 1948 INVENTOR 0 mm 6 4. pk /Wm BY M 6m P60.

ATTORNEY! Patented Mar. 9, 1954 UNITED STATES TENT OFFICE ROTARY PUMP Charles L. Pelham, Los Angeles, Calif.

Application April 5, 1948, Serial No. 19,110

1 Claim. 1.

his. nventi n r at t a r ary u ha s, r l af v aut m all as ar o t c l r in regular sequence, not, apart of its cycle, when a reversing gear is linked to a mechanical device mov n in u h se ue 0. a will a d; means is provided for controlling the flow pressure, in accordance with the characteristics and volume th l i wn, rou h t.-

The pump embodying the invention is adapted fo u e with. my newer a s n ylinder covered by my pending application Serial No. 12,491, filed March 2, 1948, now abandoned, or when the power transmission cylinder is used with my multiple sickle mower covered by my pending application Serial No. 12,492, also filed March 2, 1943, now Patent No. 2,603,052, issued July 15, 1952.

The pump is intended primarily for power transmission with a liquid propellant at moderate speed, as will be later described, claimed and illustrated in the accompanying drawings in which:

Figure 1 is a top plan view of an embodiment of the invention;

Figure 2 is a side elevational view thereof;

Figure 3 is a horizontal, sectional view of Figure 2- with the device arranged for dual intake and compression;

Figure 4 is a sectional view on the line 44 of Figure 3 Figure 5 is a sectional view on the line 5-5 of Fi e Figure 6 is a sectional view on the line 6-6 of i ur 3;

Figure 7 is a sectional view on the line 1-! of Figure 6;

Figure 8 is a detailed, elevational view of the pressure control with its barrel in section; Figure 9 is a sectional view on the line 9-9 of Figure 3;

Figure 10 is a sectional view on the line l--|0 of Figure 3;

Figure 11 is a sectional view on the. line I l-l l of Figure 3;

Figure 1 2 is a sectional view on the line I2l2 of Figure 3;

Figure 13 is a detailed, sectional view on the line l3|3 of Figure 3;

Figure 14 is a detailed, sectional view of one of the interruptors;

Figure 15. is a detailed, elevational view of the keeper er; the n srru tc hown n, F r

i hts, 16 is a. s et qhal n w he n ite-J 6 Qt F g r F g re 17 is an, elevati n l. ew Q the ha r o valv s at he righ h ad. en Q he dev ct Figure 13 is a sectional view on the line l8-.-=| 8= of Figure 17;

Figure 19 is an elevational view of the pair of valves at the left hand end of the device;

Figure 20 is a sectional view on the line 20--20 of Figure 19;

Figure 21 is a detailed perspective view ofa portion of the coacting edges of the vane and interrupter shown in Figure 14;

Figure 22 is a horizontal, sectional viewsimilar to Figure 3, with the device arranged for single intake and compression;

Figure 23 is a diagrammatic view of the device showing the direction of flow in accordance with the arrows; and

Figure 24 is a similar view showing the; opposite direction of flow in accordance with the arrows.

Referring more in detail to the drawings, the pump embodying the invention comprises a base I which, by bolts 2, is aflixed to a power take-101i housing 2' of a power source 3', as shown in Figure 2, and a shaft 3 is connected to the power source 3' by spline fittings or similar construc-.- tion. The shaft 3 is keyed to a cam 4 by keys 4 and the shaft 3. rotates cam 4 in a casing 5, which is integral with base I. Cam t is. made in two sections, an inner core which is fixed to shaft 3;, and an outer shell 6 which, in turn, rotates about the core, eliminating scraping friction against the inner wall of the casing 5.. The, core of the cam 4 is made narrower than the casing 51,. so, that the clearance between a cover I, which is secured by bolt I to the casing 5, and a bearing housing I 3 on the cover 1, as well as the clearance around the bearing below the cam 4 and the clearance between the casing 5, and; the, cam may be kept full of lubricant. The, previously men: tioned clearances communicate, with the clear: ance between the core of the cam 4 and its, outer shell 6-. Thus end play in shaft 3 is not trans-.- mitted through cam t to the casing 5, or-the cover I. For the purpose of lubrication, the; shaft; 3 is ro id h. arr su e u ri at on, d ct 3!, whic communicate w h. a rece s. n he bearing it, for lubricating and tor leakage bale ancing.

The housing, 1 is provided wit an, nlet. passa e I5 and an inlet passage 5|, for other substances orlight oil at high pressures, or a lubricating oil of higher viscosity which is placed a plunger t d h m r d i a ine connec ed either to n e It or nle 51 and t the tea sen ng t h ch h s he qnh ctich a s 8 a d 9 a n n contac ith the slee e 5 h the n 4 by mean h n es c i= i l and u. Springs it are i serted bet l- 12."

and inlet I5 respectively to engage the rear edge of the vanes 8 and 9 to urge the followers I and II into constant contact with the sleeve 6. The spring I2 in the bore I2 which engages the vane 9 is held in place by a plug I4, and the other spring I2 in the inlet I5 which engages the vane 8 is held in place by a stop and gage fitting I5. The followers I0 and II are pivotally connected or hinged to the vanes 8 and 9 respectively and these connections are made so that the followers I0 and II pivot only through about 60 degrees and. are in pivotal contact with the vanes, minimizing the slippage of fluid and placing little load on the hinge pins 8 and 9' respectively.

The sleeve 6 and vanes 8 and 9 divide the housing 5 into chambers 26 and 21 respectively. Ported rotary valves I1 and I8 are mounted in the housing 5 at the periphery of the chamber 26 and the ports in the valves I1 and I 8 communicate with the chamber 26 as will be later described. Ported rotary valves I6 and I9 are mounted in the housing 5 at the periphery of the chamber 21 and the ports in the valves I6 and I9 communicate with the chamber 21 as will be later described. As the cam rotates and the valves are in communication with their respective chambers the flow will be reversed, as shown in Figs. 23 and 24 respectively.

When valves I6 and I8 are connected to opposite ends of a. cylinder A of slightly smaller displacement travel than the pump, containing a piston P and connecting rod to a mechanical device, as shown in Figs. 23 and 24, the piston is made to reciprocate at the rate of speed at which the pump is driven. The difference in displacement is to allow for unavoidable slippage in both pump and cylinder.

Vanes 8 and 9 are shown set 01f from 180 degrees to compensate for the smaller displacement of the connecting rod end of such a cylinder and so drive said piston and mechanical device an equal distance in each direction.

"Set-off shown in these figures is 6 degrees, but may be any angle the job requires, including no degrees. Thus a pump of this type may be used to rotate a mechanical device back and forth.

In Figs. 23 and 24, it will be seen that valves I6 and I1 are connected by a duct 29 which communicates with a pressure area 58. A poppet valve 51 being positioned between the pressure area 58 and a pressure area 52 to control the passage of fluid between the areas. Thus any excess fluid which does pass through the duct 29 is diverted through the pressure areas 52 and 58 respectively. Valve I6 may be ported through tubing 61' which is connected to one end of the cylinder A. Valve I8 may be ported through tubing 61 to the opposite end of the cylinder A.

With the system full of fluid the sequence of flow in connection with the vanes 8 and 9 and valves I6, I1, I8 and I9, as pointed out above, and with the cam 4 in the position as shown in Figs. 3 and 23 and the cycle of rotation being in a counter-clock direction is as shown in Figs. 23 and 24 wherein cam 4 will force the flow of fluid in chamber 26 against the cam 4 and vane 9 and outward through valve I8 and tubing 61 to cylinder A. Further movement of the cam 4 away from valve I8 causes the flow of fluid to be out of chamber 26 into chamber 21 ahead of vane 9 the return flow from cylinder A being inwardly through tubing 61' to return to the chamber 21 through valve I6 behind cam 4. Therefore as cam 4 passes each follower. the flow behind the cam will increase until the pressure of the flow behind the cam builds up against each vane. Thus as the fluid enters the chamber 27 through valve IE, it will flow in back of cam 4 out of valve I9 into by-pass 20,,thence through valve I1 into chamber 26 behind cam 4. As cam 4 passes vane 9, flow in chamber 21 is forced against vane 8 then the flow in chamber 21 will be ahead of cam 4 outwardly through valve I6 and tubing 61 into cylinder A. Then outwardly of cylinder A, through tubing 61 and inwardly through valve I9 and then through valve I1, by-pass 20 and valve I9 to be deposited behind cam 4 in chamber 21 as in Fig. 24. In Figs. 23 and 24 the valves I1 and I9 are shown connected by the by-pass 29 and in Fig. 3 and in Fig. 23 the flow is outwardly of valve I9 and inwardly of valve I1. In Fig. 24 the flow being reversed, the flow is outwardly of valve I1 and inwardly of valve I9. In other words, as the cam rotates and the pressure of the flow builds up behind the respective vanes the flow will change from inwardly through the valve to outwardly through the same valve.

The word flow is used because in this sequence the fluid does not actually circulate through the system. With the ratio shown between the displacement of the pump and the size ofthe inlet-outlet tubing the fluid actually moves only about one foot in each direction when the pump reverses automatically.

Secured to the housing 5 is an arcuate shaped rack 23 which is adapted to be engaged by the hour glass worm 2| which is journalled in the frame 22 flxed to the base I, as shown in Fig. 5. The worm 2| is provided with a knurled nut 24 for the rotation thereof and a clamp nut in the frame 22 when turned will prevent the worm from turning once it has been manually rotated.

When it is desired to time the oscillation or reciprocation of the piston P with some other function of a machine such is accomplished by the rotation of the worm 2I and the subsequent rotation of the rack 23.

The manual control is more or less illustrative of the invention as any mechanical means now in general use may be used to rotate the worm 2 I. When the worm 2| is used, the tubing 61 and 61' must be flexible adjacent the pump.

The vane 8 on the lower edge is provided with a notch 8" and the vane 9 on its lower edge is provided with a notch 9". An interruptor 3| extends at right angles to the vane 6 and is mounted in housing 5 so that the notch 49 in the interruptor may engage the notch 8 in the vane 8. An interruptor 32 similar in structure to the interruptor 3| extends at right angles to the vane 9 and is similarly provided with a notch therein that may engage the notch 9" of the vane 9.

The valves are each provided with eccentric mounting pins 33 and the pins 33 engage in spaced slots 33' in each interruptor so that the pins 33 of valves I6 and I1 engage in the slots 33' in the interruptor 3| and the pins 33 of valves I3 and I9 engage in the slots 33' in the interruptor 32. The interruptors will stop a van and rotate the pair of valves controlled by each in opposite directions. The stem of each interruptor is journalled in a hard packing and stop 35 and a cover plate 36 isprovided for each interruptor to cover the recess in the housing 5 in which the interruptor is positioned. Screws 31 retain the plates on the housing. A soft packing gland 38 is provided for each'interruptor and aspring 34=fo1-each interruptor-reta-instheiine terruptor-inreleasedpositiom A spring loaded key 39 is. adapted-tofenga each interruptorby means of a notch in the interruptor and when the interruptoris thus engaged, its release will be delayed; until the key 39 is I struclrby cam 4 during its revolution causing the release pressure. on the interruptor. This prevents the vane'movi-ng acros the pump chamber. The vane- 8 slides. through the notch. in the interruptor when the interrupter has been released as in Fig. 9: In Fig; 14 the interruptoris shown in engagedpositionand the keys- 3$iare urged into position intothe notch inthe interruptors by means of-small springs 39 Either interrupter 3! or interruptor 32 is: simply pressed inwardly toward thepump when it is desired to interrupt automatic reversal; and the members are released in order toterminate this interruption. The valves donot cause reverse]; but theyinterrupt it. The pump will reverse automatically with the valves removed;

The automatic" reversal functions inherently as the rotating cam t passes vanes 8- and 9 in turn. As shown in. Figure 3, the fiow in chamber 26' is against vane 51 and outwardly throughvalve I 8, continuing through tubing 61. The return flowis inwardly through valve [6 to chamber 21 behind cam 4. As cam 4 progresses, the vane 3 drops. toward the center of the pump and agradually increasing portion of return flow in chamber 2 1 exits. through valve 19 to by-pass 26 then to valve l1 and into chamber 25 behind cam i. As the cam i. approaches a position opposite that shown in Figure 3, the flow in chamber 21- comes against vane 8 and; outwardly through valve iii; The return flow comes inwardly through valve l8 to chamber 25 behind earn a, and as cam. iprogresses past vane 9, a gradually increasing portion of return flow. in chamber 25. exits. through valve E1 to by-pass 29, then tovalve i9 and: into chamber 2?. behind cam i. The by-pass 29 serves. to permit fluid to enter pump from the system behind the cam t,

regardless. of its position. It is noted that valves.

i5 and it are closed to. ducts 29; andtfi and open. to. pump. chambers when the pump reverses automatically.

When a. vane is interrupted, such as vane 8,

and valves i 6 and: I1 are closed tothe pump, flow is diverted through duct 2 51 to. by-pass 2i Basically, the purpose of the automatic, reversal is. to translate rotary motion for reciprocal motion or its variants rapidly and more precisely than. is possible through the. combination of: convene. tional rotary gear pumps and reciprocating panels.

Here again manual control is. shown, but theinterruptors; may be connected to. movable mechanical devices and actuated by their move-.

ment in desired sequence by any number of; de-. vices now; in. eneral, use: (Hydraulic or pneumatic columns, electric relays, trip rods, etc).

It is noted that the advancementv of the cam 4 into the chamber 2:? while it is-still; expelling fluid from the chamber 26 does not oppose re turn flow in, the chamber 21 because the biz-pass 258 allows it to egress to the chamber 26 behind the cam 6'; and the pump is so, designed that there is no. appreciable change in displacement, and volume changes in the fluid due to variations in temperature and/or pressure ar both minimized and absorbed by pressure controls later to be described.

A removable barrel Al is fitted into the cover 1- above. the Pressure Space 53;. A. plunger. 4%

moves within the barrel 4| andthe plunger.- is;

- Projections. 2:6: on; the spring compressor engage grooves 45'. his the barrel st for the length. of: travel or the compressor-Afr only. They prevent the compressor 65: from rotatinginthe barrel 51' when a differential screw 4:83. is rotated;

- in. the spring compressor cs, advancing or retractingit, as shown-.inFig. 6.

The differential: screw 43: is. inserted through. a. removable cover 49 and the threads in the-coveri-9. inlwhichn the screw. AB-turns are: oircoarser pitch than those. in the spring compressor 45, so that. when a. hand; wheel 5'8: which is. affixed. to the; upper end of a screw: 48 is rotated; its leverageand its precision of adjustment are increased because the plunger 42 travels a distance e ual only: to. the differencev in: pitch. between the threads. in. th compressor 45 and those in the cover-49;

The advancement or retraction. of the hand wheel 50 increases or decreases the pressure Gff the fluid in the pressure space 52. The diiierem.

tial screw 48 prevents the spring 43 from coming near enough to the cover-A91 tointerfere with the function of thelslip rods Masai; and the plunger; s2 is. domed as at llg" adjacent the screw 48- to. permit the spring 41 to. compress. at the lower endof'travel' of the: plunger 42 A gage attached: to fitting 5;! communicates with the pressurespace 52: by which pressure in said space may be noted. Thus the valves I16 and t8; (moving-ahead of the cam 4:) are connectedtothe valves l1 and [9 (moving behind cam 4) via poppet valves 59, 60 and poppet valve 5:1, and with. resistance in the tubing 61: leading to. a mechanical device, such as cylinder A, Figs. 23: and 24', higher than the pressure in the space 52; fluid is looped; firom highto low side or the; cam 43 without; leaving pump.

When the hand wheel: 51!? has been advanced to establish compression, then the resistance of:

' the driven mechanism forces. the flow to be di-.

verted into the space 52' through the valve Ell on 60-, respectively; depending on which direction the flow is beingrouted by vanes. 8- and 94. The regulation of valve 5!? by/means. or an. adjusting screw as controls the resistance on the fluid as itflows out of chamber 52* and therefore is. a factor on the pressure. required to maintain valve 59 or 60 open to. flow; Up to. that prose. sure, fluid flows to the, driven mechanism. The

- flow through valve 51: becomes. the difference be.

tween the capacity or the-pumpand the require-. ment-topropel a driven mechanism. at the speed desired; Thus:v fluid entering space 29 through space- 58; creates a resistance to the return flow from the driven mechanism, subjectto adjustment or the adjusting screw 53 which contacts spring 54. A plunger 55 is inserted between the spring 54 and a spring 56 and is afilxed to valve 51. Thus the valve 51, located between pressure space 52 and pressure space 58 is maintained in a closed position by the spring 56 plus any pressure on plunger 55.

Due to the difference in area of the valve 51 and the plunger 55, a lower unit pressure in the space 58 than in the space 52 maintains the valve closed when pressure is static. The difference in unit pressure in the spaces 52 and 58 required to open or close valve 51 is variable by means of the adjusting screw 53 which uses the spring 54 to alter the relative tension of the springs 54 and 56 against the plunger 55, see Fig. 6.

When cam 4 is in motion, its tendency is to lower the pressure of the return flow entering the pump. Since valves I1 and I9 are connected by the pressure spaces 29 and and the by-pass 20 to the pressure space 58, the lowering of the pressure is reflected through the valve 5! which opens to meet this deficiency, in turn lowering the pressure in the space 52. This allows the valve 59 or 60 to open to reestablish pressure in the space 52, thus maintaining preadjusted differences in pressure between the spaces 52 and 58.

This sequence actually occurs more rapidly than the movement of the plunger can open and close the valve 51 as the plunger works between the springs 54 and 56. Thus the valve 51 fluctuates providing varying degrees of flow when the spaces 52 and 58 are out of equilibrium.

Springs 63 adjusted by adjusting screws BI and 62 permit inertia loads in a driven device to be overcome rapidly or gradually upon reversal. The valve is connected to the valve I8 by a pressure space via a pipe 66. The valve 59 is connected directly to the valve I6 via a pressure space 64. The valves I6 and I8 are open to the pressure spaces 64 and 65 when they are open to the pump chamber, closed to them when they are closed to the pump chamber. The adjusting screws and spring cases 6| and 62 have removable ends to permit assembly of valves, and have breather holes. There is a removable plug immediately above the valve 51 to permit insertion and removal of the valve and its seat. The adjusting screw 53 has a breather as has the cover 49.

With the pump aflixed to a power source as in Figure 2, and with the system full of fluid and the rotation in the same direction; but with valves I6 and I1 closed to pump and vane 9 interrupted as shown in Figure 22, and the pump connected to opposite ends of a cylinder whose displacement is X times that of the pump, or to a rotor to be driven indefinitely in one direction, the sequence of flow is as follows: With the flow ahead of the cam 4, the flow is forced against vane 9 and outward through valve I8 to a cylinder or rotor, then returns through valve I6 which is now open to duct 29 whence flow passes to valve H, bypass 20 and valve I9 to be deposited behind cam 4 as previously described, except that with only vane 9 following cam 4, as in Fig. 22 the pump now has only one chamber.

The flow will continue in this direction as long as fluid can be fed into the pump from the system, or until interrupted by interrupting vane 9, when the fluid neither enters nor leaves pump as when both vanes are interrupted, all valve ports are closed to the pump. To reverse release vane 9, when valves I6 and I! are open to the 7 pump, valve I6 closes to duct 29, valve I8 opened 8 to duct 30 when vane 9 was interrupted, making valve I6 the outlet and valve I8 the inlet-flow reversing through by-pass 20. Valve I! is open to duct 29 and valve I9 is open to duct 30 at all times. Valves I1 and I9 are alike and valves I6 and I8 are alike.

There has thus been provided a pump and a regular which, using a piston having slidable vanes, will, in operation, increase the initial pressure from multiple sources and, by reducing this increased pressure to a greater extent than the pre-adjusted pressure reduction ratio, to maintain a preadjusted difference in pressure.

Thus this system of flow of fluid by providing a relatively constant actual impelling pressure and not permitting the fluid to expand to atmospheric pressure, minimizes heat generation by alternate compression and expansion of the fluid. Also by maintaining the fluid in the system under a predetermined minimum pressure, the system uses or consumes less power in its operation.

Although the invention was primarily designed to be used with my co-pending applications before noted, it may also be used for other purposes. It may be used with gaseous propellants at high speeds by maintaining closer tolerances in manufacture, or for heat exchanging or straight transfer work.

It is believed that from the foregoing description, the manner of operation and the construction of the pump will be apparent to those skilled in the art, and it is to be understood that changes in the minor details of construction, arrangement and combination of parts may be resorted to, provided they fall within the spirit of the invention and the scope of the appended claim.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

A rotary pump comprising a casing having a fiuid therein, a base on said casing for mounting said casing to a power take ofi housing, a shaft in said casing, a cam on said shaft, an outer shell loosely mounted on said cam, vanes slidably mounted in said casing and said vanes engaging said shell at an end thereof and extending in opposite directions from said shell, said vanes providing a plurality of chambers in said casing, a plurality of inlet-outlet valves communicating with said chambers and providing an inlet and outlet for each chamber and the casing, said valves being rotatable and positioned on opposite sides of said vanes for permitting the free flow of fluid into and out of said chambers to change the pump from a reversal flow type to a steady output type, eccentric pins secured to the bottom edge of said valves, means for engaging said pins for rotating said valves and said last means is adapted to engage and stop said vanes during the operation of said valves.

CHARLES L. PELI-IAM.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 75,811 Talpey Mar. 24, 1868 1,983,997 Rolaff Dec. 11, 1934 1,996,620 Ketterer Apr. 2, 1935 2,340,196 Magrum et al Jan. 25, 1944

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