US2373449A - Pump - Google Patents

Description

April 10, 1945. E. K. BENEDEK 2,373,449

PUMP

' Filed Dec. 12, 1940 3 Sheets-Sheet, 3

s1 v 59 so /a I 0) INVENTOR ELEK K. ups/5054c ATTORNIEY- atented p Eleh 1K. Benedek, Cleveland, Ohio, assignor to The Cleveland Pneumatic liool Qompany, Qleveland, Ohio, a corporation oi Ohio Application December 1%1940, SeriaLNo. 369,852

' 7 Claims. (or. 103-161) tenance of closer tolerances and resulting in a construction particularly adapted for high production with maximum degree of accuracy.

- Another object of this invention is to arrange and dispose such reactance rings in a manner eliminating their possible misalignment and providing for them adequate bearing means enabling their free rotation.

Another object of this invention. is to provide such a pump with a-n'ovel output controlling mechanism depending for its operation upon bearing in a position corresponding to that of the power unit in Fig. 3. r Fig. 6 is a view similar to Fig. 5, but illustrating the bearing 'in a position corresponding to that of the power unit ,in Fig. 4.

Referring to the drawings, l illustrates a substantially cylindrical housing provided at one end with an integral suspension flange ii apertured as at I2 to accommodate stay bolts through which the housing may be secured to any suitable driving motor (not shown). The apertured portion of the flange H is spaced from the housing to accommodate the usual nuts cooperating with the stay bolts for securing the housing in position. The other end of the housing It is closed by an end plate or cover I3 secured in position by cap screws I4, which cover is provided with an enlarged center bore l5 having pressed therein a cylindrical pintle I6 which extends therefrom pressure variation of the fluid supp ied by the 7 pump.

Another object of this invention is the produc- 1 tion of a pump equipped with a simple and eflicient valvular mechanism and a system of inlet and outlet ports so proportioned and arranged as to enable a free flow of fluid assuring complete filling and discharge of the pump cylinders irrespective of the length of stroke of the pump pistons.

Another object of this invention is to provide-a flexible connection between the driving shaft and the driven parts of the pump, thereby preventing the driven parts from being subjected to undue stresses resulting from a misaligned drive shaft relative to such parts.

Other objects and advantages more or less ancillary to theforegoing reside in the specific construction and aggroupment of the elements peculiar to this structure, as will become apparent from a more complete examination of this specification.

In the drawings Fig. 1 is a longitudinal sectional view of a pump embodying the invention.

Fig. 2 is a cross sectional view taken in a plane indicated by line 2-2-in Fig. l.

Fig. 3 is a cross sectional view talien in a plane indicated by line 3--3 in Fig. 1 and illustrating the power unit in one operative position.

relative to the rotor.

intemally'into the housing I0 and is maintained against movement relative thereto by any suitable means such as a weld II between the pintle and the cover I3. I

Rotatabiy mounted on the pintle I6 and consequently in the housing Ill, there is arotor 88 having two hubs I8 and I8" extending therefrom in opposite directions and closely fitted for rotation on the pintle I6. The hub l8 has its outer end reduced to form a shafted portion I9 journaled within an antifriction bearing 20 mounted in the flange II against axial movement relative thereto. To prevent axial movement of the rotor I8', the bearing 20 has one of its sides resting against an annular shoulder 2| ending-the shafted portion- I9, while the other side engages aspring clip 22 integrally mounted on the shafted portion" I9. An end plate 23, mounted within a counter boreid of the flange I I, holds the bear. ing 20 in position and carries a wiper 25 active on the outer end portion of the rotor shaft I9 located within the plate 23.

The reduced portion I9 of the rotor I8 is'provided with a-flat bottom bore 26 accommodating the cylindrical head 21 of a driving shaft 28, the head being slightly smaller than the bore to permit slight lateral movement of the shaft As shown, the shaft 28 protrudes from the housing where it is provided with driving teeth 29 through which the shaft may be operatively connected with any suitable driving motor (not shown) The shaft 28 is also provided with a bore 30 forming. close to the the rotor l'8'by a cap screw 33. Due to the resiliency of the spring 32, driving shaft 28 will be free to move laterally relative to the'rotor ill to enable slight misalignment of the shaft relative to the motor without transmitting undue lateral thrusts to the rotor I8. The driving connection between the rotor I8 and the shaft 28 is shown to include two relatively small pins 34 partly carried by the rotor and partly by the shaft and calculating to transmit rotation to the rotor'under a normal condition, but capable of being sheared ofl when the rotor is subjected to an accidental load which would otherwise submit the motor connected to the driving shaft to a damaging load. 7

Intermediate its ends, the rotor I8 is provided with a double row of seven equally spaced radially extending cylinders 35, each having a cylindrical bore 36 extending axially therethrough. As shown, the inner end of each cylinder bore 36 'is somewhat reduced to form a fluid passage 31,

the purpose of which will be explained later. Each'icylinder 35 of one row is parallel to and longitudinally spaced from the juxtaposed corresponding cylinder of the other row to form a set of two cylinders united by a longitudinally extending reinforcing fin 38.

Reciprocably mounted within each cylinder bore 36, there'is a piston 39 formed with a T- shaped head 40. Surrounding the two rows of pistons 38, there are two reactance rings 4! and 42, the former or inner ring 4| being coaxially mounted within the latter or outer ring 42. The inner ring 4! hasits-peripheral wall machined to form a perfect seven sided polygon, while the outer ring 42 is internally shaped to correspond to the peripheral shape of the inner ring. The interior of'the outer ring is larger than the exterior of the inner ring to provide each side of the polygon with two perfectly parallel walls there is a band 58 provided with two diametrically opposed blocks 58 having end walls forming two parallel sliding surfaces 50 mounted between and for slidable engagement with two corresponding pads 60 protruding internally from the wall of the housing Ill. Disposed at right angles from.

able by removing or adding shims 64 between the head of the plug and the housing l0. Diametrically opposed to each compression spring 82, the housing I0 is also provided with a radially extending threaded bore 65 having mounted therein a small casing 86. This casing extends partway into the housing 10 and is provided with a cylindrical bore 81 opening through its inner end and having slidably mounted thereina preswall provided with two diametrically'opposed threaded bores 12 each adapted to receive a pipe bushing 13 through which conduits l4 and it are connected to the cover it. The conduit 16 opens into a chamber 16 provided in the cover l3 while the conduit 15 opens-into a similar chamber ll also provided in the cover. As shown in Fig. 2,

the chamber I6 is in constant communication with the pintle-l6 through a gap or opening It while the chamber ll is similarly in constant 40 communication with the pintle it through a gap forming thrust faces 44 and 46 each perfectly normal to the longitudinal center axis of its adjacent cylinder bore 88 formed within the rotor IS. The thrust faces 44 and 45 of each side of the polygon are spaced from each other to form a slot or opening 43 of a width capable of accommodating the T-shaped heads 40 oi the pistons 39, which heads are closely fittedvbetween the thrust faces 44-45 for slidable movement therebetween. Each thrust face 44 is provided with an elongated opening 46 through which the piston 39 passes.

The two reactance rings 41 and 42 are mounted between and carried by two supporting rings 41 and 48, which have their inner side walls each formed with a perfectly circular shallow groove 49 within which the reactance rings are closely fitted, thereby assuring perfect coaxial alignment of the rings. A plurality of cap screws II rigidly secure the outer reactance ring 42 to the supporting rings 41 and 48, while the inner reactance ring 4| is similarly secured to the supporting rings by cap screws 82. The supporting rings 41 and 48 are each provided with a hub I8 Journaled within a bearing 54, which bearing has its inner side wall resting against an annular step Surrounding and iitted on each 1E diametrically opposed to the gap 18. The chambers 18 and H are located within a vertical plane wherein the pintle I6 is provided with two diametrically opposed slots 80 and Bi forming between them a bridge 82, the slot 80 opening in the chamber i6 through the gap 18 while the slot 8| opens in the chamber 71 through the gap 19. Within the vertical planes passing through the two rows of pistons 89, the pintle i8 is provided with diametrically opposed slots 83 and 84 corresponding to the slots 80 and 8| respectively and also forming between them abridge 85. Fig. 3 which is taken through the vertical plane indicated by line 3-8 in Fig. 1 clearly shows the slots 83 and 84 and bridge 85 and it is to be understood that the rotor and pintle construction within the vertical plane passing through the other row of pistons shown in Fig. 1, is identical to that shown in Fig. 3. The pintle slot 80 1am constant communication with its slots 83 through two passages 88 extending longitudinally in the pintle i8, while the slot BI is similarly connected to the slots 84 through two longitudinal passages 81. In practice, the passages 86 and 8'! are drilled from the outer end of the pintle l8 and subsequently closed at that end by any suitable a means such as plugs 88.

Tapped into the conduit 14 by a suitable connection 89, there is a by-pass pipe 90 connected to the two pipes 10 by a T connection 9| In practice, the pump is fastened to a driving unit, such as a motor of any suitable type, by

bolts (not shown) extending through the holes I! 1 of the suspension flange H, while the shaft 28 is connected to the motor shaft through the drivaaraeea ing teeth as. From the shaft 28 rotation is transmitted to the rotor l8 through thedriving pins 3%. Due to the flexible connection between undue lateral thrust to the rotor or other parts of the pump. a

Normally, the bearings 54, or more particularly the whole eccentric unit which includes the reactance rings d ll2, the supporting rings 4l--49, the bearings 54 and bands 58, being acted upon by the compression springs 92 will maintain the plungers 68 at the inner end of their strokes within the casings 66, in which instance the outer end of each plunger protrudes slightly from its casing for engagement with its bearing M or more particularly with the band 59 fitted over the bearing. In this position of the plungers 68, the entire eccentric unit is located in extreme eccentric position relative to the rotary axis of the rotor l9. Assuming now-that the rotor l8 through the shaft 28 and driving pins 34 is rotated in a clockwise direction in Figs. 3 and,5, which rotation is of course transmitted to the pistons 39 carried by the rotor and from the pistons to the reactance rings 4| and 42 through the close fit of the piston heads 40 between the two thrust faces 44 and 45. The heads of the pistons 39 being thus mounted for rotation 'within a path eccentric relative to the center axis of 3?, thereby gradually filling the inner portion of the bores preparatory to the expulsion of the fluid therefrom. 'As each piston bore reaches the twelve o'clock position, its corresponding passage 31 will be closed by the bridge 95, the width of which is somewhat greater than the diameter of the passage 3'8, thereby preventing escape of the fluid from the cylinder bores into the slots' gradually be pushed inwardly, thereb causing the fluid previously sucked or drawn into the cylinderbores' 36 to be expelled therefrom by the pistons into the pintle's slots 83 through the passages 3'l, and from the slots 83 into. the outlet conduit H via the passages 36, slot 89, gap l9 and chamber 76. As each piston reaches the six oclock position, the passage 31 of its respective cylinder bore 36 will. be closed by the bridge'tfi to prevent possible communication of the slots 83 and 84 over the bridge 95.

From. the foregoing description, it will be understood that the suction strokes of the pistons 39 ar accomplished through the action of the inner reactance ring 3 I, or more particularly the action of its thrust faces 44 on the crossheads of the pistons." The inner ring thus is subjected to forces .applied in a radially inward direction at regularly spaced points. This load tends to compress or contract the ring. The compresthe rotor I3, will upon rotation of the rotor l8 I have axial reciprocation imparted thereto relative to the cylindrical bores 36 of the rotor 88, while the heads 99' of the pistons 39, due to the eccentricity between the 'axes of rotation of the rotor l8 and the reactance rings M and'M, will actually slide back and forth between the thrust faces' id and 65, the elongated opening 69 through the thrust faces M enabling this back and forth slidable or tangential movement between the inner reactance ring t! and the pistons 39. The degree of reciprocation of the pistons 39 or the length of their strokes within the cylinder bores 36 is oficourse governed by the extent of separation or eccentricity between the-rotary axes of the rotor l8 and that of'the reactance rings. In the present construction, the pintles bridges 82 and 85 are parallel to the surfaces 5901 the blocks either of the rings the load applied to any one of its polygonal faces, whether compression inthe c'ase'of the inner ring or tension in the case of the outer one, is transmittedto the adjacent parts of the ring. In otherwordsthe load, before it is transmitted to the supports for the reactance rings, is absorbed by compression or tension stresses applied lengthwise of the ring. It will be noted also that two reactance rings may be used to operate a plurality of sets of pistons, i

as herein illustrated, with no increase in the 59 slidably engaging the pads 69 which form guiding means for the reactance rings relative to the pintle l6. In other words, the longitudinal axes of the bridges 82 and 85 coincide with the sliding axis of the reactance rings 41 and 42, and

155 s since in Fig. 3 the axis of rotation of the react 'number of manufacturing operations so far as the reactance rings are concerned.

- In practice, the outlet conduit M is generally I connected to a reservoir or tank from which pressure fluid may be drawn for operating any fluid actuated mechanism such as a landing gear retracting mechanism, hydraulic engine or the like. From the outlet conduit 74, the fluid is also supplied to the plungers 38 within the casings 66 through the by-pass conduit 90, the T connection 9!, pipes it and ports ll, thereb subjecting the plungers to the action of the fluid pressure which gradually increases as the delivery of the quently of the pistons 39in a clockwise direction in'Fig. 3; the pistons'rotating from the six to the twelve o'clock position will gradually be moved out of their respective cylinder bores 36. In practice, the inlet conduit 15 has fluid supplied therewill be drawn into the cylinder bores 39 in conthe bearings 5B, the supporting rings 31 and 48 and consequently the reactance rings dl and 42 into concentric position with the rotor it. In other words, the fluid pressure active on the plungers 68 will overcome the effort of the compression springs 62 for shifting the reactance rings 4| and 42 into concentric position with the rotor I 8. During this'shift of the reactance rings.

nectlon with the slots 84 through the passages since their common axis of rotation is gradually moved closer to the axis of rotation of the rotor II. the length of the strokes of the pistons 39 will also gradually be reduced, thereby gradually re- 7 Q ducing the output of the pump. When the axis of rotation of the reactance rings and rotor flnally coincide, the pistons 39 will rotate with the rotor l8 around the pintle IS without having reciprocation imparted thereto, thereby preventing further supply of fluid to the tank even though the pump or more particularly its rotor I8 is still rotated through the drive shaft 28.

As the fluidpressure within the tank supplied by the outlet conduit H decreases, the fluid pressure active on the plungers 68 will decrease equally, thereby enablingthe compression springs. 62'

to again shift the reactance rings ll and 42 into i .will by adjusting the degree of compression of which is here rendered possible;

tlon or removal 'of shims 84 the moving parts of the pump tly filling the housing I with liquid rut; e" tsuch as oil. Upon rotation of the supporting rings 41 and 48 and the re tance rings 4| and 42, lubricant stored within the housing Ill will be dashed to the several bearings and moving parts of the pump to afford positive and efficient lubrication thereof.- Although the foregoing descrip on is necessarcylindrical inner surface, said reactance rings being disposed between said supporting rings withtheir cylindrical surfacesbearing against the radially outer and inner Walls of said grooves, and means for securing the reactance rings to the supporting rings to constitute a rigid connection between the supporting rings, said reactance rings having facing polygonal surfaces equal in number to said cylinders, and said pistons having crossheads bearing against said polygonal surfaces.

4. In a rotary piston pump, a rotor having a plurality of radially arranged cylinders open at their outer ends, pistons in said cylinders, an eccentric unit revoluble about an axis parallel to the axis of said rotor, reactance means carried by said unit for reciprocating the pistons, two bearings for said eccentric unit spaced lengthwise of the pump axis, said bearings being independentl ly movable toward or away from the axis of said ily of a detailed character, in o'rd "to completely set forth the invention, it is to derstood that the specific terminology is not-intended to be restrictive or confining and it isto-beiurther understood that various rearrangements of parts and modifications of structural detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.

I claim:

1. In a rotary piston pump, a rotor having a plurality of radially arranged cylinders open at their outer ends, pistons in said cylinders, an eccentric unitcomprlsing supporting means revoluble about an axis parallel with but eccentric to the axis of said rotor, a one-piece outer reactance ring and a one-piece inner reactance ring both carried by said supporting means, said rings having facing polygonal surfaces equal in number to said cylinders, and said pistons having crossheads bearing against said polygonal surfaces.

2. In a rotary piston pump, a rotor having a plurality of radially arranged cylinders open at their outer ends, pistons in said cylinders, an

eccentric unit comprising supporting means revoluble about an axis parallel with but eccentric to the axis of said rotor, said supporting means comprising a pair of supporting rings, a onepiece outer reactance ring and a one-piece inner reactance ring disposed between said supporting rings and forming exclusivemeans for rigidly connecting said supporting rings, said reactance rings having facing polygonal surfaces equal in number to said cylinders, and said pistons having crossheads bearing against said polygonal surfaces.

' 3. In a rotary piston pump, a rotor having a plurality or radially arranged cylinders open at rotor, and adjusting means for exerting equalized fluid pressure upon said bearings for moving them in a given direction.

5. In a rotary piston pump, a housing, a rotor mounted therein having a plurality of radially arranged cylinders open at their outer ends, pie-- tons in said cylinders, an eccentric unit revoluble about an axis parallel to the axis of said rotor, reactance means carried by said unit for reciprocating the pistons, two ball bearings for said eccentric unit spaced lengthwise of the pump axis, a steel band surrounding and gripping the outer race of each of said bearings, and coacting guide means on said housing and on each of said steel bands for controlling the direction of movement their outer ends, pistons in said cylinders, an,

of said bearings during the adjustment of the ble pistons in said cylinders, an elongated eccentric unit surrounding said rotor for rotation therewith and connected to said pistons for imparting reciprocation thereto upon its rotation on an axis parallelly spaced from the rotary axis of said rotor, bearing means for the longitudinal ends of said unit, guiding means for said hear ing means enabling movement of said unit into variable distance of its rotary axis from that of said rotor, resilient supporting means for said bearing means, and distance controlling means between the rotary axes of said rotor and unit including a pair of fluid actuated elements concurrently active on said bearing means for maintaining said axes in parallel relation.

'7. In an apparatus of the class described, the combination of a housing having a rotor extending longitudinally therein and a fluid tight seal carried by the housing inoperative engagement with one end portion of the rotor, a blind bore within said one'end portion of the rotor, a'rotor driving memberin said bore, resilient fastening means between said rotor and-member enabling limited rockingmovement or the latter relative to the former, and a rotation transmitting connection between said rotor and member.

ELEK K. BENEDEK.

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