US3447476A

US3447476A - Rotary fluid device

Info

Publication number: US3447476A
Application number: US641246A
Authority: US
Inventors: Edward L Farris
Original assignee: EDWARD L FARRIS
Current assignee: EDWARD L FARRIS
Priority date: 1967-05-25
Filing date: 1967-05-25
Publication date: 1969-06-03
Anticipated expiration: 1986-06-03

Description

June 3, 1969 E. L. FARRIS 3,447,476

ROTARY FLUID DEVICE Fild May 25, 1967 EDWARD L. fZ/P/P/S June 3, 969 E. L. FARRIS 3,447,476

ROTARY FLUID DEVICE Filed May 25, 1967 Sheet 2 of 2 ,yi; (awn A TTO/PA/EY United States Patent 3,447,476 ROTARY FLUID DEVICE Edward L. Farris, Baldwin Park, Calif. (12251 Bluebell Ave., Garden Grove, Calif. 92640) Filed May 25, 1967, Ser. No. 641,246 Int. Cl. F04c 1/04, 21/08 US. Cl. 103136 8 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to fluid pressure devices. More particularly, the invention relates to a radial vane type rotary fluid pump and motor device characterized by novel rolling ball sealing vanes.

Rotary fluid motors and pumps of the class to which this invention pertains are well known in the art. Generally speaking, such a rotary fluid pressure device comprises a rotor member and a stator member which are mutually supported for turning of the rotor on an exis of rotation relative to the stator. One member, i.e. the outer member, has a sealed casing containing the other, inner member, whereby the members have confronting circumferential surfaces. Extending radially between the members are a number of uniformly circumferentially spaced sealing vanes which are carried by one member, for radial extension and retraction relative thereto, and are retained in fluid sealing relation to the confronting circumferential surface of the other member. In most rotary fluid motors and pumps of this kind, for example, the outer casing member forms the stator, and the inner member carries the radial sealing vanes and forms the rotor. The inner and outer members and the sealing vanes define a number of working fluid chambers between the adjacent vanes and uniformly circumferentially spaced about the axis of relative rotation of the members.

The radial distance between the rotation axis of the members and the inner circumferential wall of the outer casing member varies progressively around the axis in such a way that during rotation of the rotor, each working chamber undergoes alternate expansion and contraction. The casing is provided with fluid ports which open to the interior of the casing for successive communication with the working chambers during their expansion and contraction modes, respectively. Pump operation of such a fluid pressure device is accomplished by driving the rotor from an external power source. Motor operation is accomplished by supplying high pressure working fluid to the appropriate fluid port of the device.

A major disadvantage of the existing rotary fluid pumps and motors of the character described resides in the relatively high frictional losses which occur during their operation. These fractional losses result from the fact that the sealing vanes employed in the existing pumps and motors commonly comprise plates, or the like, which are urged into fluid sealing relation with and slide along coacting sealing surfaces. In addition to undesirable friction loss, of course, such sliding vane action produces excessive Wear and shortens service life.

It is a general object of this invention to provide an improved radial vane-type rotary fluid pump and motor which avoids the above-noted and other disadvantages of the existing fluid pumps and motors of this kind.

A more specific object of the invention is to provide an improved radial vane-type fluid pump and motor wherein the sealing vanes comprise spherical rollers or balls which undergo a rolling motion along their mating sealing surface, during relative rotation of the rotor and stator, in such a way as to minimize friction loss and wear and maximize operating efliciency.

A further object of the invention is to provide a rolling ball vane rotary fluid pump and motor of the character described which is relatively simple in construction, reliable in operation, and otherwise ideally suited to its intended purposes.

Other objects, advantages, and features of the invention will become readily evident as the description proceeds.

With these and such other objects in view, the invention consists in the construction, arrangement, and combination of the various parts of the invention, whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims, and illustrated in the accompanying drawings.

In these drawings:

FIGURE 1 is a side elevation of a rolling ball vane type rotary fluid pump and motor device according to the invention;

FIGURE 2 is an enlarged section taken on lone 22 in FIGURE 1;

FIGURE 3 is a section taken on line 3-3 in FIG- URE 2;

FIGURE 4 is a section through a modified rotary fluid pump and motor device according to the invention;

FIGURE 5 is a section through a further modified pump and motor device according to the invention;

FIGURE 6 is a section taken on line 6-6 in FIG- URE 5; and

FIGURE 7 is an interior view of onehalf of the casing of the pump and motor device illustrated in FIGURES 5 and 6.

In general terms, the invention provides a rotary fluid pump and motor device, represented in FIGURES 1 through 3 by the fluid pump and motor device 10, including an outer member 12 having a sealed casing 14. Within the casing 14 is an inner member 16 which is supported on the casing for relative rotation of the members on an axis 'of rotation 18. One of the members, in this instance the outer casing member 12, is formed, within the casing, with a generally tubular circumferential track 20 of substantially uniform and generally semicircular transverse cross section. Track 20 opens radially, along one side, toward the other, inner member 16 and is bounded along its opposite side by a circularly curved wall 22. Track 20 as a longitudinal centerline 24, and the track boundary wall 22 has a substantially constant radius of curvature about the centerline 24, along the entire length of the track.

The other member of the rotary fluid pump and motor 10, ie the inner member 16, is formed with a number of radial bores 26 which have substantially the same radius as and open axially to the track 20 in the outer casing member 14. Slidably fitted in the bores 26 are a number of spherical rollers or balls 28 which function as and will be hereinafter referred to as sealing vanes, or simply vanes. The ball vanes 28 project axially from their respective containing bores 26 into the track 20 and into rolling, fluid sealing contact with the track boundary wall 22. As will appear presently, means are provided for retaining the ball vanes 28 in the track 20, whereby the vanes undergo rolling motion along the track during relative movement of the

members

12 and 16.

The outer member 12, inner member 16, and ball vanes 28 define a number of fluid chambers 30 between the adjacent vanes and uniformly circumferentially spaced about the inner member. The radial distance from the rotation axis 18 to the centerline 24 of the channel 20 varies progressively along the channel, in such manner that during the relative rotation of the

members

12 and 16, the ball vanes 28 undergo radial extension and retraction in their respective retaining bores 26, and each fluid chamber 30 undergoes alternate expansion and contraction. The casing 14 of the outer member 12 is provided with

fluid ports

32 and 34 which open to the interior of the casing for successive communication with the chambers 30 during their expansion and contraction modes; that is to say, port 32 communicates with the chambers bearing their expansion mode and port 34 communicates with the chambers during their contraction modes. The arrangement of the present fluid pressure device is such that the latter is operative as a pump when the

members

12, 16 are driven in relative rotation by an external power source and as fluid motor when high pressure working fluid is supplied to the port 32 of the pump.

Referring now in greater detail to the rotary fluid pump and motor of the invention which has been selected for illustration in FIGURES 1 through 3, the outer member 12 forms the stator and the inner member 16 forms the rotor of the device. The stator casing 14 is split, in a parting plane 36, into two mating halves 14a, 14b which are bolted to one another or otherwise joined. The two casing halves are sealed to one another with the aid of a gasket or other suitable sealing means (not shown). Rotor 16 of the fluid pressure device 10 has a generally flat disc-shaped body 38 with parallel side faces 40 disposed in fluid sealing relation to the side walls 42 of the casing 14. Rotor 38 is coaxially fixed to a shaft 44 which extends through and is rotatably supported in bosses 46 on the casing side walls. Suitable sealing means (not shown) are provided for sealing the shaft to the casing.

In the illustrated fluid motor and pump device 10, the outer stator casing 14 contains the tubular channel 20, and the inner rotor 16 contains the ball,vane bores 26. Thus, the interior of the casing 14 has a central region 48 which contains the rotor body 38 and is parametrically surrounded by the ohannel 20. This channel opens radially along its inner side to the central casing region 48. As shown best in FIGURE 2, the peripheral edge of the rotor body 38 projects radially into the channel through its open side. It is significant to note here that the axial thickness of the rotor body is slightly less than the diameter of the channel and the outer circumferential edge of the body is rounded to a radius which is substantially the same as the radius of curvature of the channel boundary wall 22. It will be recalled that the diameter of the ball vane bores 26 in the rotor 16 and the diameter of the ball vanes 28 contained in these bores is substantially the same as the diameter of the channel boundary wall 22 in the transverse cross section.

As noted earlier, and as clearly shown in FIGURE 3, the radial distance from the rotation axis 18 of the rotor 16 to the centerline 24 of the stator channel 20 varies progressively around the channel. As a consequence, the fluid working chambers 30 between adjacent ball vanes 28 undergo alternate expansion and contraction, and the vanes themselves undergo relative extension and retraction relative to the rotor body 38, during rotation of the rotor. Thus, in the particular fluid pressure device illustrated,

each working chamber undergoes an expansion stroke or mode during rotation from A to B and a contraction stroke or mode during rotation from B to C in FIGURE 3. During rotation from C back to A, the working chambers of the illustrated device remain in their fully contracted, minimum volume condition. This is due to the fact that the radial distance from the rotor axis 18 to the stator channel centerline 24 remains constant at its minimum value in the region between C and A.

It is evident, of course, that operation of the present fluid pressure device as both a pump and a motor requires the ball vanes 28 to remain within and move along the stator casing channel 20, in fluid sealing relation to the channel boundary wall 22, during rotation of the rotor 16. To this end, the angular extent of the channel boundary wall, in transverse section and about its centerline 24, is slightly in excess of Also, the side faces 40 of the rotor body 38 are formed with radial slots 50 aligned with the ball vane bores in the rotor and through which the ball vanes 28 in the bores project axially of the rotor into contact with opposite sides of the channel wall, as shown best in FIGURE 2. Thus, the ball vanes are captivated or caged in the channel 20 for rolling movement along the channel and against inward radial movement from the channel through its inner openside. To further aid in retaining the ball vanes in fluid sealing relation with the channel boundary wall 22, the inned ends of thhe ball vane bores 26 communicate via passages 52 with body 38. Successive inward movement of the rotor vanes 28 in their respective bores 26, therefore, displaces fluid from these bores into the other ball vane bores to urge the ball vanes 28 in the latter bores outwardly into fluid sealing relation with the channel boundary Wall 22.

During operation of the fluid pressure device 10 as a pump, the rotor shaft 44 is coupled to a power source for driving the pump rotor 16 in either direction in FIGURE 3. Assuming clockwise rotation of the rotor in FIGURE 3, it is evident that working fluid will be drawn through the casing port 32 into the expanding working chambers 30 in the region A-B, and working fluid will be expelled from the contracting working chambers in the region B-C through the casing port 34. Driving of the rotor in the opposite direction will effect a reverse pumping action. It is significant to note that within the lower, constant radial distance portions C-A of the casing channel 20, the rounded peripheral edge of the rotor body 38 is disposed in close proximity to the channel boundary wall 22 to provide the working chambers 30 with minimum volume within this region. It is for this reason that the edge of the rotor body is rounded to the same radius of curvature as the channel boundary wall.

Operation of the fluid pressure device 10 as a fluid motor is accomplished by connecting one of the

fluid ports

32, 34 to a source of high pressure working fluid and the other port to a low pressure fluid receiver. Under these conditions, the high pressure fluid entering each expanding working chamber 30 exerts a torque on the rotor 16 for driving the rotor in a direction to cause further expansion of the chamber until the latter eventually communicates with the low pressure port. The working fluid is then exhausted from the chamber during its subsequent contraction.

The modified fluid pressure device 10a of FIGURE 4 is identical to the fluid pressure device 10 just described, except that the lower constant radial distance portion C-A of the ball vane channel 20 in the device 10 is replaced, in the fluid pressure device 10a, by a lower channel portion, the radial distance of which from the rotor axis 18 varies in the same manner as does the channel in the upper channel portion A-C. Also, the fluid pressure device 10a has

additional fluid ports

32a, 34a opening to the lower channel portion so as to communicate successively with the working fluid chambers 30a in the lower channel portion during the expansion and contraction modes of the chambers which occur in the lower channel portion.

It will now be understood, therefore, that in the modifled fluid pressure device 10a, each working chamber 30a undergoes two expansion strokes or modes and two contraction strokes or modes during each revolution of the rotor 16a, and the device produces elfective working strokes of the chambers throughout a full 360 of rotation of the rotor. Operation of the modified fluid pressure device as a pump is accomplished by driving the rotor 16a from an external power source, as before. Fluid is then drawn into the pump through one pair of diametrically

opposed ports

32a or 34a and is expelled through the other ports. Operation of the device as a motor is accomplished by communicating the corresponding

ports

32a or 34a to a high pressure fluid source and the remaining ports to a low pressure fluid receiver. If desired, the corresponding ports, i.e. the two ports 32a and the two ports 34a, may be interconnected by piping, in the manner illustrated in FIGURE 4, to effectively provide the device with a single fluid inlet and a single fluid outlet.

The modified fluid pressure device 10b of FIGURES through 7 is a fluid pump which differs from the earlier fluid pressure devices in that the rotor body 38b of the pump 10b has passages 52b which communicate the inner ends of the ball vane bores 26b with the adjacent Working chambers 3012, as shown, so that reciprocating motion of the ball vanes 28b in their respective bores produces a pumping action in addition to that produced by expansion and contraction of the working chambers. In addition, the inner casing channel b in the pump 10b is circular, rather than elliptical as in the earlier embodiments of the invention, and is eccentrically disposed relative to the rotor axis 18b. Finally, the casing 14b of the pump 10b has internal circumferential grooves 54b which provide communication between the pump ports 32!), 34b and the Working chambers b during expansion of the chambers from and subsequent contraction of these chambers to their minimum volume condition.

It will now be understood that the rotary fluid pump 1% of the invention produces, in effect, a compound pumping action involving the primary pumping action resulting from expansion and contraction of the working chambers 30b and a secondary pumping action resulting from extension and contraction of the ball vanes 28b in their respective containing rotor bores 2611. A major advantage of all the disclosed forms of the present fluid pressure device, of course, resides in the fact that the

ball vanes

28, 28a or 28b, as the case may be, undergo rolling movement, rather than sliding movement, along the interior surfaces of the outer casing 12. As a consequence, frictional losses and wear are reduced to an absolute minimum and the operating efficiency of the device is maximized.

It is now evident, therefore, that the invention herein described and illustrated is fully capable of attaining the several objects and advantages preliminarily set forth.

Although specific embodiments of the present invention have been illustrated and described herein, it will be understood that the same are merely exemplary of presently preferred embodiments capable of attaining the objects and advantages hereinbefore mentioned, and that the invention is not limited thereto; variations Will be readily apparent to those versed in the art, and the invention is entitled to the broadest interpretation Within the terms of the appended claims.

What is claimed is:

1. A rotary fluid pump and motor device comprising:

an outer member having a sealed casing,

an inner member supported in said casing for relative rotation of said members on an axis of rotation, one of said members having within said casing a circumferentially extending channel of generally semicircular transverse cross section opening radially along one side toward the other member and bounded along its opposite side by a circularly curved wall,

said channel having a longitudinal centerline disposed in a transverse plane of said axis and said boundary wall having a substantially constant radius of curvature about said centerline along the entire length of said channel, said other member having a number of generally uniformly circumferentially spaced radial bores of substantially the same diameter as said channel,

spherical ball vanes slidably fitted in said bores, respectively, and projecting axially from said bores into said channel and into rolling fluid sealing contact with said channel boundary wall,

the circumferential extent of said channel boundary Wall about and in a transverse plane of said centerline being slightly greater than whereby said vanes are caged in and undergo relative rolling movement along said channel during relative rotation of said members,

said members and vanes defining a number of fluid chambers between the adjacent vanes, respectively, and circumferentially spaced about said inner member, and the radial distance from said axis to said centerline varying progressively about said channel in such manner that during relative rotation of said members, each chamber undergoes alternate expansion and contraction, and

said casing having first and second fluid ports opening to the interior of said casing for communication with said chambers during their expansion and contraction modes, respectively, whereby said device is operative as a pump by driving said members in relative rotation and as a motor by supplying high pressure working fluid to one fluid port.

2. A fluid pressure device according to claim 1 wherein:

said outer member contains said channel and said inner member contains said bores and carries said ball vanes.

3. A rotary fluid pump and motor device comprising:

an outer member having a sealed casing,

an inner member supported in said casing for relative rotation of said members on an axis of rotation,

one of said members having within said casing a circumferentially extending channel of generally semicircular transferse cross section opening radially along one side toward the other member and bounded along its opposite side by a circularly curved wall,

said channel having a longitudinal centerline disposed in a transverse plane of said axis and said boundry wall 'having a substantially constant radius of curvature about said centerline along the entire length of said channel,

said other member having a number of generally uniformly circumferentially spaced radial bores of substantially the same diameter as said channel,

spherical ball vanes slidably fitted in said bores, re-

spectively, and projecting axially from said bores into said channel and into rolling fluid sealing contact with said channel boundary wall,

the angular extent of said channel boundary Wall about and in a transverse point of said centerline being slightly in excess of 180,

said other member projecting radially through the open side of said channel and having axially presented end faces with radial slots opening to said bores, respectively, through which said ball vanes protrude into contact with said channel boundary wall, whereby said ball vanes are caged by said channel for endwise movement along and against radial movement from said channel,

4. A fluid pressure device according to claim 3 including:

passage means communicating the closed ends of said bores, whereby working fluid displaced from certain of said bores in response to inward movement of the ball vanes therethrough is effective to urge the remaining ball vanes outwardly and to fluid sealing relation to said channel boundary wall.

5. A fluid pressure device according to claim 3 including:

passage means communicating the closed ends of each bore to an adjacent fluid chamber, whereby said fluid pressure device is operative as a fluid pump with a compound pumping action involving expansion and contraction of said working chambers and extension and retraction of said ball vanes in their respective bores.

6. A rotary fluid pump and motor device comprising:

an outer member having a sealed casing,

one of said members having within said casing a circumferentially extending channel of generally semicircular transverse cross section opening radially along one side toward the other member and bounded along its opposite side by a circularly curved wall,

said channel having a longitudinal centerline disposed in a transverse plane of said axis and said boundary wall having a substantially constant radius of curvature about said centerline along the entire length of said channel,

means for retaining said ball vanes in said channel,

whereby said vanes undergo relative rolling movement along said channel during relative rotation of said members,

said members and vanes defining a number of fluid chambers between the adjacent vanes, respectively, and circumferentially spaced about said inner member, and the radial distance from said axis to said centerline varying progressively about said channel in such manner that during relative rotation of said members, each chamber undergoes alternate expansion and contraction,

said casing having first and second fluid ports opening to the interior of said casing for communication with said chambers during their expansion and contraction modes, respectively, whereby said device is operative as a pump by driving said members in relative rotation and as a motor by supplying high pressure working fluid to one fluid port,

said outer member comprising a stator containing said channel, and said inner member comprising a rotor containing said bores and carrying said ball vanes,

the angular extent of said channel boundary wall about and in a plane transverse to said channel centerline being slightly in excess of and said rotor having axially presented end faces disposed in fluid sealing relation to side walls of said casing and radial slots opening through said faces into said bores, respectively, through which said ball vanes protrude into contact with said channel boundary wall, whereby said ball vanes are caged by said channel for enwise movement along and against radial inward movement from said channel, and

the periphery of said rotor projecting into said channel through open side thereof, and the outer peripheral edge of said rotor being rounded to a radius approximating the radius of curvature of said channel.

7. A fluid pressure device according to claim 6 wherein:

said casing is split into two mating halves along a parting plane normal to said axis and containing said channel centerline.

8. A fluid pressure device according to claim 7 wherein:

said rotor end faces are generally flat and disposed in planes normal to said axis,

said casing has inner planar sealing surfaces disposed in fluid sealing relation to said rotor end faces, and

the diameter of said channel is slightly greater than the axial spacing between said sealing surfaces.

References Cited UNITED STATES PATENTS 888,838 5/1908 Muller. 1,580,162 4/ 1926 Peterson. 1,965,872 7/1934 Webb et a1. 2,241,607 5/1941 Long.

JAMES W. WESTHAVER, Primary Examiner.