US2679352A - Rotary pump - Google Patents

Description

May 25, I954 H. P. VANCE 2,679,352

ROTARY PUMP Filed Jan. 14, 1954 3 Sheets-Sheet l INVENTOR HAROLD P. VANCE BY M HIS ATTORNEY H. P. VANCE May 25, 1954 ROTARY PUMP 5 Sheets-Sheet 2 Filed Jan. 14, 1954 FIG.7

F.IG.6

HIS ATTORNEY May 25, 1954 H. P. VANCE 2,679,352

ROTARY PUMP Filed Jan. 14, 1954 5 Sheets-Sheet 3 INVENTOR.

'HAROLD P. VANCE Hi5 ATTORNEY Patented May 25, 1954 ROTARY PUMP Harold P. Vance, Ripley, N. Y., assignor to General Electric Company, a corporation of New York Application January 14, 1954, Serial No. 404,026

2 Claims.

My invention relates to pumps and more particularly to pumps of the rotary type.

It is an object of my invention to provide an improved rotary pump having an increased efficiency.

It is a more specific object of my invention to provide an improved ball pump of the type disclosed in the Patent 2,611,534 to Kirkpatrick, including provision for preventing leakage from the high pressure side of the pump to the intake thereof.

In carrying my invention into effect I utilize the basic pump structure disclosed in the Kirkpatrick patent. This structure includes a spherical rotor rotating within a spherical hous ing, the rotor being provided with two intersecting grooves each of which has a piston segment positioned therein. The pumping action is accomplished by means of the action of these piston segments upon fluid fed into the grooves from recesses positioned in the spherical surface of the housing member. In accordance with my invention, I have incorporated in this basic structure means for preventing leakage from the hi h pressure side to the intake thereof, which leakage occursv in the basic structure at one posi tion of the piston segments unless check valves or the like are provided. This means comprises a novel and improved arrangement of the intake recesses into two diametrically opposite pairs thereof, each of which pairs cooperates with a different one of the grooves. The two recesses of each pair are transversely disposed on opposite sides of a plane extending between the ends of the piston segments and perpendicular to the axis of the rotor thereby causing the recesses in each pair to communicate alternately with the cooperating groove thereof. Further the transverse spacing between the recesses of. each pair of intake recesses is such that the communication between the intake recesses and the grooves is broken when the ends of the piston segments are in the regions of the intersection of the grooves. By the breaking of the communication between the intake recesses and the grooves, the communication between the discharge recesses and the intake recess is also broken and thereby leakage flow between the high pressure side and the intake is prevented at that position of the piston segments wherein it could possibly occur in the basic structure.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and method of operation may best be understood by reference to the following description taken in conjunction with the accompanying drawings in which:

Fig. 1 is a view, partially broken away, of a refrigerating unit including a compressor embodying my invention;

Fig. 2 is an enlarged view of the rotor of the compressor showing the piston segments 'in one position thereof;

Fig. 3 is a view similar to Fig. 2 showing the piston segments in another position thereof;

Fig. 4 is an enlarged plan view, partially broken away, of the compressor shown in Fig. 1, and illustrating the piston segments in still another position thereof;

Fig. 5 is another view of the rotor showing? the piston segments in a still different position thereof; and

Figs. 6-9 are developed views of the rotor and its associated parts in positions of the rotor corresponding to those shown in Figs. 2-5 respectively.

In the following description my new and improved pump is described in connection with. its application as a compressor in a refrigerating apparatus, but it will be apparent that it may be utilized in many other applications where pumpof fluid is required. Referring now to Fig. 1', I have shown therein a hermetically sealed. case I within which is mounted a compressor 2. The compressor is positioned within the housing by rings 3 and d which fit grooves in the case I and engage opposite faces of the compressor 2. The compressor is driven in any suitable manner as by an electric motor (not shown) incorporated within the case I and connected to the compressor through the drive shaft 5. Compressed. refrigerant is discharged from the compressor through conduits 6 and 1 into a common conduit 8 from which it is circulated through the refrigerating. system (not shown). vaporized refrigerant is returned from the refrigerating system through a conduit 9 which discharges the refrigerant into the interior of the case I. vaporized refrigerant within the case I is taken into the compressor through intake conduits 0 and I l the open ends of which are positioned above the level IQ of any liquid refrigerant or oil within the case I.

As shown in more detail in Fig. 4 the shaft 5 for driving the compressor is supported within a bearing 13. The bearing is itself mountedv by means of the compressor housing M which. includes two complementary parts l5 and It. The inner surface of each of the housing parts- 15 and is is curved so that when the two parts are assembled a spherical surface, forming a spherical chamber, is provided within the interior of the housing. In the form shown the housing parts are of such width that the ends of the sphere formed by the inner surfaces thereof are truncated. However, if desired, the housing could be enlarged and the inner surfaces of the" parts It and 16 continued to provide a substantially complete sphere. The housing parts l5 and [6 are held in sealing engagement by devices such as screws I! which pass through the upper housing part I5 and are arranged in threaded engagement with the lower housing part 16.

A rotor I8 is provided within the housing, the rotor being driven by the shaft 5. The outer surface of this rotor is curved to provide a generally spherical surface having the same radius of curvature as the inner surface of the housing so as to rotate smoothly in engagement therewith. In the form shown, the rotor also is truncated providing fiat faces 19 and H311. An arcuate ring 20 which fits within a groove 2! in the housing and engages the face lSa of the rotor may be employed to assist in resisting oscillation of the axis of rotation of the rotor, although reliance for this purpose may be placed entirely on bearing l3.

The rotor is provided with two circumferential grooves 22 and 23. each other at diametrically opposite points of the rotor, one said such intersection being indicated at 24 and the other at 24a (see Figs. 6-9). These grooves are inclined at equal angles with respect to a plane perpendicular to the axis of rotation of the rotor and extending through the two points 24 and 24a of intersection of the grooves 22 and 23. In order to effect pumping of fluid. a piston segment 25 is positioned within the groove 22 and a similar piston segment 26 is positioned within the groove 23. The outer spherical surfaces 21 and 28 respectively of the piston segments 25 and 25 are in line with the spherical surface of the rotor 18 and hence are in engagement with the spherical surface provided by the interior of housing l4. Each of the piston segments is in the form of a semi-circular or half-annular section extending on a great circle of the rotor I8 substantially half the circumference thereof.

To effect pumping of fluid by the compressor, it is necessary to restrain the piston segments 25 and 26 against rotation with the rotor while permitting lateral oscillation of the segments during such rotation of the rotor. complished by providing a pin or projection on each of the said piston segments pivotally engaging a slide or block which is slidably positioned within a transverse slot or recess in the housing l4. Thus in the drawing one such slide or block 29 is shown pivotally connected by a pin 30 to the piston segment 26. It will be understood that exactly the same construction is employed at the diametrically opposite point for pivotally connecting the slide or block 3| to the piston segment 25. As shown the slides 29 and 3| respectively are slidably positioned for transverse movement, i. e. movement generally transverse of the piston segments, within elongated recesses 32 and 33 formed in the housing adjacent rotor 18.

The pumping is accomplished in the structure herein disclosed in the same manner as in the basic pump structure disclosed in the Kirkpatrick Patent 2,611,534. However, in accordance with my invention I have provided means which prevent leakage from the high-pressure side of the pump to the intake. This leakage preventing means comprises a new and improved system for introducing the fluid to be pumped into the grooves. Specifically it comprises two pair of diametrically opposite recesses. One pair of these recesses is shown in Figs. 2-5 whereas the other pair may be seen by referring to the developed views 6-9. The pair viewable in Figs.

These grooves intersect This is ac- 2-5 includes the recesses 34 and 35 whereas the diametrically opposite pair shown in the developed views comprises the inlet recesses 38 and 31. The one pair of these recesses, i. e. 34 and 35, are connected to intake conduit H and the diametrically opposite pair 36 and 31 are connected to the intake conduit in. This connection of the intake conduit to the recesses thus provides intake ports for the compressor, and consequently these recesses will hereinafter be denominated inlet recesses. The one pair 34 and 35 is positioned to cooperate with the groove 22 and the other pair 36 and 31 is positioned to cooperate with the groove 23.

As shown in the diagram the two recesses of each pair of intake recesses are transversely disposed on opposite sides of a plane extending between the intersection of the grooves and perpendicular to the axis of the rotor. This causes the two recesses of each of the pairs to communicate alternately with the cooperating groove thereof. The transverse spacing between the recesses of each pair, as for example between recesses 34 and 35, is however, such that the communication between the intake recesses and housing 14 adjacent rotor 18 two elongated transverse recesses 33 and 39. These elongated recesses 33 and 39 are connected respectively to the discharge conduits 6 and 1, and will hereinafter be referred to as the discharge recesses. t will be noted that each of these discharge recesses 38 and 39 is positioned adjacent one of the pairs of intake recesses. Thus the discharge recess 38 is positioned adjacent intake recesses 34 and 35 and the discharge recess 39 is positioned adjacent the intake recesses 36 and 31. Further these respectively adjacent inlet and discharge recesses are so positioned in the housing that the respectively adjacent ends of the piston segments lie in the area between the adjacent inlet and discharge recesses. In other words, the one ends of piston segments 25 and 26 lie between inlet recesses 34 and 35 and discharge recess 38 whereas their other ends lie between the inlet recesses 36 and 31 and the discharge recess 39. More simply it may be said that the adjacent intake and discharge recesses are circumferentially spaced on opposite sides of the cross-over points of the piston segments. The cross-over points as used in this specification indicate the positions of the intersections 24 and 24a of the grooves 22 and 23 when the ends of the piston segments are positioned therein. Such a position is shown in Fig. 4 and also occurs when the rotor is rotated therefrom.

The pumping is accomplished in my new and improved structure herein disclosed in the same manner as in the basic pump structure shown in the Kirkpatrick Patent 2,611,534, and the pumping action may be clearly understood by reference to that patent. However, as mentioned above my new and improved inlet means prevent leakage from the high-pressure side of the pump to the intake thereof, and in order to explain the manner in which, my improved means so operate, I have shown the rotor 18 in four different positions thereof in Figs. 2-5 and the corresponding developed, views; 6-9. In each or the figures the rotor is shown as. positioned4'5" from. its position in. the prior figure. Thus, in Fig: 2; the rotor is shown at its posiiton 90 before reaching one. of the cross-over points, in. Fig. 3 at a position 45 before that cross-over point, in Fig. i. at the cross-over point and in Fig; 5. at 45 after the cross-over point; For convenience in description and, for clarity the intake recesses 35,35, 36, and 311 and thedischarge recesses 38 and 39 have been superimposed in dotted lines onthe: rotor in the various figures.

As illustrated, the rotation of the rotor ass a. lateral shifting of the piston segments and also a rotational movement of the rotor with respect i to the piston segments since the segments are restrained against rotation by the blocks 29 and 31. Each additional rotational increment of the rotor thus causes the shifting of, the parts to a new position. As explained in the Kirkpatrick patentthe result of this action is: that each of the piston segments simultaneously sheets. a pumping of fluid from one of, the grooves and blocks the other groove so as to act as a barrier against which the other piston segment efiects compression of fluid. Further, each segment divides the groove in which the other segment is positioned intotwo portions, into one of. which fluid is. taken and from the other of which fluid is discharged during the relative movement. of the segments a caused by rotation of the rotor.

This. pumping action. may be understood by reference to the various figures starting with Fig. 2 whereinthepiston. segment blocks the groove 23 as shown. at 40 and the piston segment 26 blocks the groove 22' as indicated at 4|. In that position the inlet recess communicates with the portion of groove 22 lying between blocking face. ll and the end 42 of segment 25, and similarly the discharge recess 38 communicates with the portion of the groove 23 lying between the blocking face and the end 33 of piston segmentZS. During the movement from the position shown in Fig. 2 to that shown in Fig. 3- the distance between the end 42 of the piston segment 25 and the blocking face or side 41 of the piston segment 26 increases and fluid is therefore drawn into this portion of the groove 22. through the inlet conduit H and the inlet recess 35. Simultaneously the groove 23 has moved relative to the piston segment 25 which is positioned within the groove 22 so that the length of the portion of the groove 23 between end 43 of piston segment 26 and the blocking face or side dd of the piston segment 25 is decreasing. This results in a compression of fluid in this portion of the groove 23 and discharge of the fiuid through the recess 38 and the conduit 6.

As shown clearly by the developed views 6 an:

7 this same action is simultaneously occurring on the other side of the housing. Fluid is being taken into the portion of groove 23 lying on the other side of piston segment 25 through the inlet recess 3'! and is being discharged from the other portion of recess 22 through discharge recess 39. Thus each groove includes a portion increasing size into which fiuid is being taken and a portion decreasing in size from which fluid is being discharged.

This discharging action continues progressively until the cross-over point shown in Fig. 4: is reached. However, in accordance with my invention the intake recesses are so positioned that as the rotor continues to move from the position shown in Fig. 3 to the cross-over position shown in Fig. 4",. the communication between the: inlet recesses 35. and 31' and the. grooves 22 and. 231 respectively-is broken... In other words sometime before the rotor reaches the cross-over position the communication between the grooves 22 and 23 and the intake. of thepump. is broken. Hence, even. though the; discharge conduit is still connected to the grooves at the cross-over point;

through the discharge recesses 38 and 39, reverse flow between it and the intake cannot'take place.

As shown by Figs. 5' and 9, the communication is not again established between the intake. recesses and the groove until the rotor has rotated a considerable degree past the cross-over point. Thus, in Figs. 5 and 9 wherein the rotor is shown at past the cross-over point, the inlet recesses are still not in communication with the grooves. This insures that the ends 43 and M respectively of segments 26 and 25 will have. passed beyond the intersections 24 and 24a and again block communication between the two grooves before the inlet ports are again open. It should be understood, however, that the spacing of the inlet recesses need not necessarily be exactly the same as those illustrated nor need the recesses be exactly of the same size as those illustrated. Some variation in both spacing and size maybe had without departing from my invention. Obviously, the inlet ports could be opened somewhat sooner or somewhat later than those illustrated and yet still be closed duringthe cross-over period of the segments. The two recesses of each pair should, however, be spaced apart a distance somewhat greater than the width of the intersections 24 and 24a, and should be'spaced on opposite sides of a plane extending between the intersections and perpendicular to the axis of the rotor, such spacing or positioning being necessary to insure both closing of the recesses during the cross-over periods and proper communication with the grooves during the pumping action.

As the rotation of. the rotor continues, communication will be established between intake recess. 34 and the portion of the groove 22 lying between end 42 of segment 25 and the face 45 of segment. 26, and between intake recess 35 and the portion of the groove 23 lying between end 46 of segment 26 and the face 47 of segment 25 (shown in Fig. 9). This allows the entry of fluid, and fluid will continue to be drawn into these portions of the grooves until conimunication at the inlet ports is again broken somewhat before the cross-over point spaced from Fig. 4 is reached.. Since my pairs of spaced intake ports are positioned. diametrically opposite from each other and since the cross-over points. are 180 apart, the result is that the intake ports are shut off at the second cross-over point just as they are at the first illustrated in Fig. 4. This, ofcourse, prevents leakage-between the discharge and the intake just as in the same manner as in Fig. 4'. During the half rotation between the position shown in Fig. 4 and the position spaced 180 therefrom,,fiuid will of course be discharged from the progressively decreasing portions. of the grooves filled during, the previous. half rotation and. now in, communication with the discharge recesses.

Incidentally, it. should be realized, as shown by the exploded views, that the fluid admitted through recesses. 34, and 35 into groove 22 is always discharged at recess 39 whereas that admitted through recesses 36 and 31 into groove 23 is always discharged at recess 38. No matter which half rotation the rotor is in relative to Fig. 4. the pumping action occurs between the remote intake and discharge recesses and not between the adjacent thereof.

It should be noted however that only one intake recess of each pair thereof communicates with its cooperating groove during each half-revolution of the rotor. Thus, during the half revolution following Fig. 4 it is the intake recesses 34 and 36 which are in communication with the grooves 22 and 23 whereas in the prior half-revolution partially described above, it is the intake recesses 35 and 3'! which are in communication with the grooves. In other words, the two intake recesses in each of the two diametrically opposed pairs of intake recesses communicate alternately with the cooperating groove thereof. Specifically the two recesses 3 and 35 communicate alternately with groove 22 and the other two recesses 36 and 31 communicate alternately with groove 23. As mentioned above, however, in accordance with my invention, the transverse spacing between the two recesses of each pair is such that the communication between the intake recesses and the grooves is completely broken when the ends of the piston segments are in the regions of the intersections of the grooves. In other words, communication with the intake conduit is broken during the cross-over periods of the piston segments and this prevents leakage flow between the discharge recesses and the intake recesses. At all other positions of the rotor a positive pumping action is taking place and there is then, of course, no leakage problem.

Thus, it may be seen that through my invention I have provided an improved ball type pump in which leakage between the high-pressure discharge and the intake is effectively prevented. Through the use of my diametrically opposite, spaced pairs of intake recesses communication between the intake conduit and the grooves is completely broken during cross-over of the piston segments, whereby there cannot possibly be any leakage flow between the discharge and the intake of the pump.

Now, in accordance with the patent statutes, I have described what at present is considered to be the preferred embodiment of my invention. However, it should be obvious to those skilled in the art that various changes and modifications may be made therein without departing from my invent-ion, and I, therefore, aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. A pump comprising a housing having a spherical chamber therein, a rotor positioned within said chamber and having a spherical surface arranged to engage the surface of said chamber, said rotor having a pair of circumferential grooves formed in the spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semi-circular piston segment positioned in each of said grooves, said housing having two elongated diametrically opposite discharge recesses and two diametrically opposite pairs of intake recesses formed in said surface of said spherical chamber adjacent said spherical surface of said rotor, each pair of intake recesses being positioned adjacent one of said discharge recesses, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, said means maintaining the respectively adjacent ends of said piston segments in the areas between the adjacent of said discharge and inlet recesses, said discharge recesses extending transversely with respect to said grooves and each of said discharge recesses communicating with a different one of said grooves, each of said pairs of intake recesses cooperating with a different one of said grooves, and the two recesses of each pair of intake recesses being transversely disposed on opposite sides of a plane extending between the intersections of said grooves and perpendicular to the axis of said rotor to cause the two recesses of each pair to communicate alternately with the cooperating groove thereof, the transverse spacing between said recesses of each pair of intake recesses being effective to break the communication between said intake recesses and said grooves when the ends of said segments are in the regions of the intersections of said grooves thereby to prevent leakage flow between said discharge recesses and said intake recesses.

2. A pump comprising a housing having a spherical chamber therein, a rotor within said chamber, said rotor having a truncated spherical surface adapted to engage the surface of said chamber, said rotor having its axis of rotation perpendicular to the faces of the truncated portions thereof, said rotor having a pair of circumferential grooves formed in the spherical surface thereof, said grooves intersecting each other at two diametrically opposite points, a semi-circular piston segment positioned in each of said grooves, said housing having two elongated diametrically opposite discharge recesses and two diametrically opposite pairs of intake recesses formed in said surface of said spherical chamber adjacent said spherical surface of said rotor, each pair of intake recesses being positioned adjacent one of said discharge recesses, means for maintaining said piston segments against rotation with said rotor while permitting lateral oscillation of said segments, said means maintaining the respectively adjacent ends of said piston segments in the areas between the adjacent of said discharge and inlet recesses, said discharge recesses extending transversely with respect to said grooves and each of said discharge recesses communicating with a different one of said grooves, each of said pairs of intake recesses cooperating with a different one of said grooves, and the two recesses of each pair of intake recesses being transversely disposed on opposite sides of a plane extending between the intersections of said grooves and perpendicular to the axis of said rotor to cause the two recesses of each pair to communicate alternately with the cooperating groove thereof, the transverse spacing between said recesses of each pair of intake recesses being effective to break the communica tion between said intake recesses and said grooves when the ends of said segments are in the regions of the intersections of said grooves thereby to prevent leakage fiow between said discharge recesses and said intake recesses.

References Cited in the file of this patent UNITED STATES PATENTS Number

Images