Leonard J. Keller KROV Steam Engine : simple, superior design uses saturated steam rather than superheated; articles & patents

US3883277
Rotary vane device with improved seals
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Abstract
An eccentric rotor vane device that may be employed as pumps, blowers (or compressors), engines, or motors, characterized by an improved seal structure; in addition to conventional main chamber; first and second ports communicating with the main chamber; a plurality of annularly related radial vanes, independently pivotal and rotatable about a vane axis within the main chamber; a rotor that is eccentrically mounted with respect to the main chamber; a power delivery shaft connected with the rotor. The improved seal means, in specific embodiments, comprises a plurality of cylindrical rollers that serve as vane guides intermediate each pair of adjacent vanes. The cylindrical rollers adjacent each face of each respective vane engages its lateral face such that a satisfactory seal is made as the roller traverses radially inwardly and outwardly along the lateral face of the vane. Thus, the plurality of rollers serve as at least a part of a piston as well as an interdigitating means for effecting a change in volume of a subchamber defined intermediate the respective vanes, rollers, and interior wall in the main chamber. Also disclosed are improved vane structures for maintaining more nearly perfect seals for long service life.

1. Field of the Invention

This invention relates to an improvement in eccentric rotor, concentric vane devices that may be employed as pumps for pumping incompressible fluids, blowers for compressing and pumping compressible fluids, as engines powered by internal combustion of a fuel using either spark ignition cycle or the diesel cycle, or as motors powered by compressible or partially incompressible fluids.

2. Description of the Prior Art

Eccentric rotor, concentric vane devices have been known at least since the middle of the 19th century; U.S. Pat. Nos. 43,744 and 83,186 being granted, respectively, in 1864 and 1868 on rotary steam engines. Subsequently, there has been at least eighteen different United States patents issued on similar structures for one or more of the uses delineated hereinbefore. Yet, not a single one of the patented devices, insofar as I am aware, has achieved widespread commercial use. The failure to be widely useful is generally conceded to be due to lack of having a satisfactory seal between the vanes and the vane follower, or vane guide, portion of the rotor that interdigitates the vanes. The seal means attempted before my invention have either allowed too much leakage to be practical or have imposed too much frictional resistance to movement to allow the machines sufficient mechanical efficiency to be practical. The early attempts; the intermediate attempts, such as exemplified by U.S. Pat. No. 2,129,431; and very recent attempts, such as delineated in U.S. Pat. No. 3,572,985, employed semi-cylindrical seal members slidably engaging each side of planar vanes as they slid radially inwardly and outwardly along the vanes. Other patents, such as U.S. Pat. No. 2,022,209, described employing a seal having a knife-like edge that engaged planar vanes, attempting to seal as it moved radially inwardly and outwardly along the vanes. None effected the desired satisfactory seal. In my U.S. Pat. No. 3,748,068, I delineated an improved seal structure that solved the problems of the prior art; including the art cited in that patent. With experience in different embodiments, alternative seal structures have been found to be equally efficacious and provide unobvious advantages over the prior art. For example, it has been found desirable to provide independent rolling friction intermediate respective rollers contiguous respective vane faces for effecting a low frictional drag and long life.

Accordingly, it is an object of this invention to provide an eccentric rotor vane device that obviates the disadvantages of the prior art structure.

Specifically, it is an object of this invention to provide an eccentric rotor vane device having an improved seal between the interdigitating portion of the rotor and adjacent vanes throughout the full 360 ( DEG) of rotation of the rotor such that the interdigitating portion can operate as a piston, as well as a vane guide and employ rolling friction intermediate a roller contiguous each adjacent face of each vane; regardless of whether the rotor vane device is being employed as a pump, blower, engine or motor.

It is also an object of this invention to provide a rotor vane device having the same advantages as delineated in U.S. Pat. No. 3,748,068 and still provide the foregoing objects.

These and other objects will become apparent from the descriptive matter hereinafter, particularly when taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cross sectional view from the side of one embodiment of this invention.

FIG. 2 is a partial cross sectional view from the side showing a sleeve serving as an internal wall in the main chamber, rotor, vanes, vane guides, and the respective seals therebetween in accordance with another embodiment of this invention.

FIG. 3 is a partial cross sectional view from the side showing a sleeve, rotor, vanes, vane guides, and the respective seals therebetween in accordance with another embodiment of this invention.

FIG. 4 is a partial cross sectional view from the side showing a sleeve, rotor, vanes, vane guides and the respective seals therebetween in accordance with still another embodiment of this invention.

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DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIG. 1, there is illustrated one embodiment of this invention in the form of a motor 11, or eccentric rotor, concentric vane motor device. The motor 11 comprises a stator 13; a rotor, or rotor assembly, 15; and a vane assembly 17. The motor 11 is described in detail in my copending patent application entitled "Rotor Vane Motor Device", Ser. No. 227,393, filed Feb. 18, 1972, now Pat. No. 3,797,975; and the descriptive matter contained therein is embodied by reference herein for complete description of the construction and operation of the motor. In that application, the motor described was a variable torque, vairable power motor employing the improved seals described in my aforementioned U.S. Pat. No. 3,748,068; and having improved torque and power control means. The descriptive matter of U.S. Pat. No. 3,748,068 is also incorporated herein by reference. In view of the aforementioned U.S. Pat. No. 3,748,068 and the patent application Ser. No. 227,393, now U.S. Pat. No. 3,797,975, the following abbreviated description is believed adequate and is afforded merely for the convenience of the reader to prevent having to refer to the delineated patent and patent application.

The stator 13 includes a main body member 19 having a base or mounting bracket 21. The main body member 19 has peripherally disposed circular flanges (not shown) for affixing cap members at each side of the motor 11, or each end of a main chamber. A longitudinal cylindrical cavity 23 is formed in the inner face of the main body member 19 and includes a main chamber. An inlet port 25 is formed in the inner face of the main body member 19 and extends from the medial top, or 0 DEG, position thereof for about 50 DEG clockwise. The inlet port 25 has its leading and trailing edges 27 and 29 extending longitudinally for the full length of the main body member 19 for providing maximum flow area. The inlet port 25 communicates via passageway 31 in main body member 19 with a collar 33 to facilitate connecting an inlet of motor 11 with a high pressure source of working fluid, as described in detail in Ser. No. 227,393, now U.S. Pat. No. 3,797,975. Similarly formed in the inner face of the main body member 19 is an exhaust, or discharge, port 35. The discharge port 35 has a leading edge 37 that extends longitudinally of the longitudinal cylindrical cavity 23 and main body member 19, and that is spaced about 25 DEG peripherally thereof from the trailing edge 29 of the inlet port 25. The discharge port 35 also has a trailing edge 39 that extends longitudinally of the longitudinal cylindrical cavity 23 and trails the leading edge 37 by approximately 90 DEG. The discharge port 35 communicates via passageway 41 in the main body member 19 with a collar 43 to facilitate connection with a low pressure receiver, as described in the aforementioned Ser. No. 227,393 now U.S. Pat. No. 3,797,975.

The pair of cap members at each side of the main body member 19 and their attachments thereto is described in detail in Ser. No. 227,393, now U.S. Pat. No. 3,797,975. Similarly described therein, are the mechanical accessories enabling rotation of the rotor and its shaft. The described accessories include; for example, the coaxial bearing sleeves that are integrally formed with the cap members; the thrust plate that is secured to the bearing sleeve by cap screws with a seal therebetween; the coaxial collar that is secured by cap screws to the outer end of the bearing sleeve and disposed about the rotor shaft extending therethrough; together with the respective shaft seals and bearings.

As described in the above referenced Ser. No. 227,393, now U.S. Pat. No. 3,797,975, the end caps also define exhaust or discharge chambers disposed longitudinally exteriorly of the openings in respective annular plates 49 disposed annularly about the rotor assembly 15, the latter being described in more detail hereinafter. The annularly disposed plates 49, as illustrated, have a plurality of discharge apertures 85 for discharging the fluid. The respective annularly disposed plates 49 may be rotated by suitable pinion gear or the like (not shown) to advance or retard the second set of discharge apertures 85 for further refinement in torque control, similarly as described in Ser. No. 227,393, now U.S. Pat. No. 3,797,975.

The rotor assembly 15 includes a pair of opposite and mating circular plates 45 at each end. The plates 45 engage, or proximate, the circular apertures 47 in the annularly disposed plates 49. If desired, bearing materials can be provided at the interface between the respective circular plates 45 and the inner walls of the apertures 47. The follower means, such as the vane guides 51, are retained intermediate the oppositely disposed faces of the circular plates 45 at each end of the rotor 15. The vane guides 51 serve as both pistons and means for interdigitating the vanes, thereby effecting a change in volume of subchambers 53 intermediate the respective adjacent vanes as the rotor assembly and the vanes are rotated within the main chamber. Each subchamber 53 is defined by a pair of confronting vane faces on its sides, a vane guide 51 and an interior surface 55 of a torque control sleeve 57 at its radially inner and outer boundaries, and the annular plates 49 at its ends. Each subchamber 53 varies from a minimum volume at the outermost, or 0 DEG, position of the vane guide 51 to a maximum at the innermost, or 180 DEG, position of the vane guide 51. The vane guide 51 traverses inwardly and outwardly radially along the adjacent vanes to effect the improved seal that makes practical this invention, as described later hereinafter in more detail with respect to the vanes and the vane assembly.

Each of the illustrated follower means comprises a vane guide 51 that extends longitudinally along the rotor with vane engaging surface contiguous the lateral face of the vane. As illustrated, each vane guide comprises a plurality of cylindrical rollers 59 that are rotatably mounted on a shaft 61. Rotation of each cylindrical roller 59 is facilitated by suitable bearing means, such as insert 63. As illustrated and described in U.S. Pat. No. 3,748,068, each shaft 61 is fixed between shoulders (not shown) of the circular plates 45 by cap screws penetrating through apertures in the circular plates.

As indicated hereinbefore and as described in U.S. Pat. No. 3,748,068, a power shaft 65 is affixed to and extends coaxially from the circular plates 45 to the respective roller bearings in the bearing sleeves in the respective ends (all not shown). As indicated, the shaft 65 of motor 11 is journalled within coaxial collars and shaft seals and extends outwardly to deliver, as by way of suitable coupling means, power to using apparatus. If the device 11 is being employed as a pump or blower, the shaft delivers power to the rotor 15.

The respective coupling means may be any of the conventional coupling means, including but not limited to linear in-line couplers, gear reducing couplers, or properly sized sheaves and endless member drives; such as belts or chains. As in conventional practice, one end of the coupling means will be connected with the shaft; as by key and slot combination, or splines (not shown).

A second shaft also extends coaxially from the opposite circular plate 45 and is journalled for rotational movement in its roller bearings in bearing sleeves to provide additional support for the rotor assembly 15.

As described in Ser. No. 227,393, now U.S. Pat. No. 3,797,975, each of the shafts 65 has a male threaded portion that threadedly engages a tapped aperture in respective circular plates 45 when the shafts are threaded into tapped apertures, respective shoulders are pulled into tight engagement with the exterior of the respective circular plates 45 to form a strong connections therebetween. The threads are formed such that they are not loosened in normal rotation. Respective sets of roller thrust bearings are provided intermediate the exterior of the respective circular plates 45 and the adjacent end caps (not shown). If desired, thrust bearings may be counter sunk to keep the clearance intermediate the plates to a minimum. Preferably, aircraft type roller bearings are employed as thrust bearings, although other bearings may be employed as appropriate to the use of the device, or motor 11. Bearings provide improved structure and should not be omitted casually.

The rotor assembly 15 is eccentrically disposed within the longitudinal cavity 23, and its power shaft 65 is eccentric with respect to the central axis of the longitudinal cavity 23.

The vane assembly 17 is located in a vane assembly cavity 67 that is defined by the sleeve 57 concentrically within the longitudinal cavity 23. The vane assembly 17 includes a floating axle pin, or shaft, 69 that is substantially coaxial with the longitudinal cavity 23 and extends between the circular plates 45 of the rotor assembly 15. A plurality of vanes 71 extend radially outwardly from the axial pin 69 and are individually pivotal thereon. As illustrated, each vane is provided with a curved end plate 73 of substantially the same radius of curvature as the inner surface 55 of the sleeve 57. The curved end face 73 of each vane is in substantial sliding engagement with the sleeve 57 such that it forms a satisfactory seal for confining the fluid in the respective subchambers 53 on either side thereof. The seals intermediate the vanes 71 and the sleeve 57 have not been particularly critical because the differential pressure between adjacent subchambers 53 is not inordinately high and because the centrifugal force on the vanes 71 tends to retain sufficient sealing engagement between the respective vane ends 73 and sleeve 57. Any type of seal appropriate to the vane ends 73 may be employed, as described in the aforementioned Ser. No. 227,393 now U.S. Pat. No. 3,797,975 and U.S. Pat. No. 3,748,068. The radially exterior end 73 of the respective vanes may be formed as desired to minimize the volume in the subchamber defined between the radially outermost ends of adjacent vanes. For example, the vanes 71 may have arcuate intruding shoulders to more closely fit the respective plurality of cylindrical rollers 59 of the rotor assembly 15 to reduce the volume to near zero.

As described in detail in Ser. No. 227,393 now U.S. Pat. No. 3,797,975, each of the vanes 71 has integrally formed with the inner radial end thereof at least one annular knuckle 75 that conformingly engages the axle pin 69. The knucles 75 of respective vanes 71 are axially offset relative to each other along the axle pin 69 and are stacked on the axle pin with their confronting faces in sliding engagement to permit the relative interdigitating, or rocking, of the vanes 71 about the axle pin 69. It will be appreciated that; as specifically illustrated in the aforementioned U.S. Pat. No. 3,748,068; the vane central knuckle is twice as wide as ordinary and disposed intermediate the adjacent knuckles on either side. If desired, the vanes may have the respective knuckles disposed at one-half of the axle pin 69 plus the thickness of one knuckle and intermesh such that the use of the wide central knuckle is obviated. Any other method of supporting the vanes that will allow the interdigitating thereof may be employed. Since the vanes are accelerated and decelerated during rotation, however, symmetrical arrangement of the knuckles with respect to a transverse plane through the vane's center is preferable.

The respective vanes 71 have lateral faces 77 that are concaved inwardly toward the central plane of the vane such that the respective followers, or vane guides, 51 are maintained in substantially uniform sealing engagement with the vane lateral faces 77 as the vane guides 51 traverse radially inwardly and outwardly therealong during rotation of the rotor assembly 15. By substantially uniform sealing engagement is meant an engagement such that a satisfactory seal is maintained intermediate the respective vane guides 51 and the vanes 71 so that the vane guides 51 can serve as pistons as well as interdigitating means as they traverse radially inwardly and outwardly along the respective vanes 71.

As is well recognized, what is satisfactory sealing engagement will vary depending upon the application, or use; which determines several pertinent factors. These factors include the size of the unit, the differential pressure across a vane guide 51 from the subchamber to the interior of the rotor assembly 15, the total pressure of the fluid being handled in the subchamber and the efficiency desired. To illustrate, I have found that as much as 0.010 inch clearance may be tolerated between the vane guides 51 and the vane lateral faces 77 with large motors such as may be employed with low pressure steam. For example, with low pressure steam that may be emitted from geothermal wells, the motor device may have dimensions as large as 30 inches in length by 36 inches in diameter; or larger, if used on individual steam wells. On the other hand, when employing the motor with a low entrophy fluid flowing therethrough, I have found it preferable that a clearance of less than 0.005 inch; for example, about 0.001-0.003 inch; be employed between the surfaces of the vane guides 51 and the vane lateral faces 77. Lighter motors may be only about 4 inches in length and 6 inches in diameter, yet develope enough power to operate a small automobile.

The improved seal means of this invention, as described hereinbelow, makes practical the eccentric rotor, concentric vane motor of this invention, that has all of the advantages of the invention of U.S. Pat. No. 3,748,068 and the aforementioned Ser. No. 227,393 now U.S. Pat. No. 3,797,975. This improved seal preferably employs a plurality that is an even number of cylindrical rollers 59 intermediate each pair of adjacent vanes 71. By this structure, each of the rollers 59 engages respective lateral faces 77 of the vane contiguous therewith, as well as engage the surface of any adjacent cylindrical roller 59 with rolling friction. Thus, reduced friction is effected for more efficient operation. Moreover, there is substantially no wear and the wear is evenly apportioned, because of the rolling interconnection between contiguous surfaces, the rolling of contiguous surfaces being in the same direction, or compatible rather than opposite, for still less friction. Consequently, the improved seal means is durable and trouble-free, the cylindrical rollers rolling along the vane faces and in contact with each other.

As noted in U.S. Pat. No. 3,748,068 and Ser. No. 227,393 now U.S. Pat. No. 3,797,975, I have attempted to delineate, through mathematical experts and computer computations, the exact definition of the concavity of the lateral faces 77 but have not been successful to date. The concavity can be delineated graphically, employing a scale that is larger than actual size. I have developed an empirical formula by trigonometry which is close also. In practice, I have found exact mathematical delineation to be unnecessary. Instead, I employ a grinding jig with grinding rollers to duplicate the physical relationships and dimensions employed in a particular motor device 11. Specifically, the grinding of the vane faces is effected by repeatedly moving the vanes and sized grinding rollers through 360 DEG as the vanes are moved by the rotor assembly 15, with increasing distances of eccentricity up to the eccentricity actually employed in the motor device 11. By increasing distances of eccentrically is meant the increasing moving apart, with successive revolutions, of the shaft of the vane axle pin 69 and the axis of the shaft of the grinder rollers that is equivalent to the axis of the shaft of the rotor assembly 15, as described in Ser. No. 227,393 now U.S. Pat. No. 3,797,975. In this way, I get exact initial engagement and do not have to worry about the clearance. Once a particular vane contour, or concavity, has been established for a particular motor, it may be reproduced by conventional methods of copying.

In the above referenced Ser. No. 227,393 now U.S. Pat. No. 3,797,975, there was described an integral adjusting flow through and torque control means for controlling torque output of the motor 11 so that it could be operated without requiring a throttle and the throttle-caused losses in efficiency. That does not comprise a part of this invention, per se, and need not be described in detail herein. It is sufficient to note that the flow through and torque control means comprises the torque control sleeve 57, delineated hereinbefore, that is conformingly disposed interiorly of the longitudinal cylindrical cavity 23. The torque sleeve 57 mates with and telescopes within the cavity 23 and rotatably and slidably engages the inside face of the cavity to permit angular adjustment of the torque control sleeve 57. The torque control sleeve has at least an inlet aperture in the form of a first set of longitudinally extending slots 79. The inlet slots 79 communicate between the interior of the vane assembly cavity 67 and the inlet port 25. It is sufficient to note in the abbreviated description herein that advancing of the torque control sleeve by suitable gear 81 will increase the effective flow area through the inlet apertures until the inlet aperture is at a maximum. On the other hand, the torque control sleeve 57 may be retarded or rotated in a second direction opposite the first direction to decrease the effective flow area of the inlet aperture and inlet port. The degree of retardation may be sufficient to completely close off the inlet port or to effect a reduced flow of fluid through the motor. The respective means for controlling the gear 87 is described in detail in Ser. No. 227,393 now U.S. Pat. No. 3,797,975 and is not shown or described herein.

Also, the use of discharge slots 83 to control the discharge independently for reducing losses from over expansion or under expansion of a working fluid flowing through the motor 11 was described in detail in Ser. No. 227,393 now U.S. Pat. No. 3,797,975.

In operation, a fluid will enter through the inlet passageway 31 and inlet port 25, entering into the respective subchambers 53 at their minimum volume position near the top. The point of entry may be controlled by the torque control sleeve 57. The fluid is preferably an expansible fluid that will do work as it expands to effect rotation of the respective vanes and act against the respective vane guides, or plurality rollers 59, serving as a piston. This forces rotation of the rotor assembly and the work output shaft as the fluid expands to the maximum position near the bottom. Shortly past the bottom, the fluid will be vented through a second set of discharge apertures 85 in the annularly disposed plates 49, or through the discharge slots 83 and discharge port 35, depending upon which are set earlier by the respective torque control means. Thus, as each subchamber is rotated, the fluid contained therein is allowed to do work and deliver power from the motor 11 before the fluid is begun to be discharged in its fully expanded condition directly to the pressure existing in the discharge passageway 41, without any throttle control losses. The respective sealing surfaces on the respective plurality of rollers 59 remain contiguous and in sealing engagement with a rolling action to minimize friction and wear.

Another embodiment of this invention is illustrated in FIG. 2. Therein, only a portion of the torque control sleeve 57 is illustrated since the environment is the same as described hereinbefore with respect to FIG. 1. As illustrated in FIG. 2, each respective vane guide 51 comprises two cylindrical rollers 59A and 59B that are affixed by their respective shafts 61 to the circular plates 45, similarly as described hereinbefore. As illustrated in FIG. 2, however, the respective plurality of rollers 59A and 59B are not contiguous each other, but are contiguous an intermediate member 87. Specifically, the respective cylindrical rollers 59A and 59B engage the respective seals 89 and 91 that are sealingly engaged in recesses in the coextensive and longitudinally extending intermediate member 87. Expressed otherwise, the intermediate member 87 extends coextensive with the respective rollers 59A and 59B longitudinally of the rotor assembly 15 and is sealingly affixed to the circular plates 45, similarly as are the shafts 61 of the rollers.

As illustrated, the respective vanes 71 have their vane lateral faces 77 contoured to maintain the desired sealing engagement with the surfaces of the respective rollers 59A and 59B, as described hereinbefore with respect to the lateral faces 77 of the vanes 71. Otherwise, the structure of the vanes, with their axle pin 69; the vane assembly 17; the rotor assembly 15; the main body member 19 and the respective inlet and discharge ports 25 and 35 are the same and the operation is the same as described with respect to the embodiment of FIG. 1.

Thus, it can be seen that in the embodiment of FIG. 2, the respective rollers 59A and 59B engage their respective contiguous vane lateral faces 77 with a rolling action as the vane guides 51 move radially inwardly and outwardly along the vanes 71. This rolling action attains the desired lowered friction and reduced wear, similarly as described hereinbefore with respect to the embodiment of FIG. 1. If desired, the intermediate memberr 87 may have a plurality of roller bearings for sealingly engaging the rolling surface of the respective cylindrical rollers 59A and 59B, instead of or in addition to the respective seals 89 and 91.

Still another embodiment of the invention is illustrated in FIGS. 3 and 4. In FIG. 3, the same embodiment about the torque sleeve 57 is employed as described with respect to FIG. 1. Similarly, the same cylindrical rollers 59 are employed as the vane guides 51, as described with respect to FIG. 1. In the embodiments of FIGS. 3 and 4, however, each vane 71 comprises first and second members 93 and 95 that are biased toward their respective contiguous rollers 59 for maintaining the satisfactory sealing engagement therewith. Respective first and second members may comprise simply a bifurcated end of an integral vane in which the physical properties of the material of which the vane is made biases the first and second members toward their respective rollers 59. As illustrated, however, the second member 95 is pivotally mounted such that its radially outermost end is biased away from the radially outermost end of the first member 93. The pivotal mounting may comprise simply a quasi-cylindrical head 97 that is embedded in a suitable slot 99 in the main body of the vane, with or without an inherent bias being effected. On the other hand, one or both of the first and second members may be sealingly mounted on a fulcrum shaft if desired. Sealing of the quasi-cylindrical head in a conforming slot 99 is more easily effected. It is apparent, however, that the use of a vane 71 having a bifurcated end forming the first and second members 93 and 95 automatically effects sealing and overcomes the problem with sealing, although it is relatively expensive to form the slot intermediate the bifurcated members.

In the embodiment of FIG. 3, the first and second members have a spring member 101 seated in respective recesses 103 and biasing the radially outermost ends of the respective vanes 71 toward their respective contiguous rollers 59.

In the embodiment of FIG. 4, the space intermediate the respective first and second members 93 and 95 is filled with a compressible material for effecting the biasing of the radially outermost ends of the vanes 71 toward their respective contiguous rollers 59. As illustrated, the compressible material is the compressible fluid that is being flowed through the motor 11, FIG. 1. If desired, the compressible material may be a resilient material such as the elastomeric materials like rubber. The elastomeric material should be resistant to the fluid being flowed through the motor. For example, the synthetic rubbers like Neoprene or Buna N, may be employed satisfactorily.

The embodiments of FIGS. 3 and 4 operate similarly as described hereinbefore with respect to the embodiments of FIGS. 1 and 2. It is noteworthy, however, that good sealing contact is made because of the flexibility and the biasing of the bifurcated first and second members toward their respective contiguous rollers 59. The resulting compressive force exerted on the contiguous rollers 59 also assists in maintaining sealing contact between the respective surfaces of the rollers as wear develops between the respective shafts and inserts 61 and 63.

The operation of the motor 11 as a pump or air compressor is described in the hereinbefore referenced U.S. Pat. No. 3,748,068 and that descriptive matter need not be repeated herein.

The materials of construction ordinarily employed in this art may be employed herein and no exotic new materials are necessary. The structural strength and the wearing properties of the materials that interface together will be chosen appropriate to the application. For example, in certain applications it may be possible to employ plastics to reduce the friction as they interface with adjacent metallic components. In general, we have been working with the most deleterious types of materials, such as steam, and have employed noncorrodable metals in those surfaces in contact with such materials, or fluids.

It is noteworthy that when the device is employed as an air compressor, or blower, similarly as described in U.S. Pat. No. 3,748,068, it has many advantages that are not found in the ordinary blowers. For example, in centrifugal blower embodiments, there is no problem of balancing; since the rotor assembly 15 may be run with up to several pounds out-of-balance mass in the larger sizes. This is in contrast to only a few ounces, or less of imbalance that is tolerable in conventional blowers. For example, I have designed a large diameter unit to serve as a centrifugal blower that will deliver up to five million standard cubic feet per minute of air for use in magneto hydrodynamics applications. There is no conventional blower that can presently supply this amount of air. The use of rolling friction with the improved plurality of cylindrical rollers enables employing large size units without intolerable friction.

From the foregoing, it can be seen that a highly efficient positive displacement device is provided that finally achieves all of the advantages heretofore known but not practically achieveable because of the difficulty with seals intermediate the rotor assembly and the vanes. Specifically, this invention provides a rotor vane device that achieves the objects delineated hereinbefore and obviates the disadvantages of the prior art devices. Its size and weight are unbelieveably more compact and lighter than conventional air compressors. The use of roller vane guides, with the attendant rolling friction, effects a long-wearing, trouble-free seal that is an important advance in the technology to improve our ecology. The rotor vane device also makes practical an essentially nonpolluting engine that may be used as an expander in an external combustion Rankine cycle system.

Moreover, as disclosed in U.S. Pat. No. 3,748,068, the large changes in volume of the subchambers allow unusually large variation in compression ratios when the rotor vane device is employed as an engine.

Also, the numerous advantages of the motor 11 are described in the above reference Ser. No. 227,393 now U.S. Pat. No. 3,797,975. These numerous and lengthy advantages are not repeated herein, although this invention also provides these same advantages over the art prior to the above described Ser. No. 227,393 now U.S. Pat. No. 3,797,975.

A wide variety of other embodiments employing the basic improved seal are feasible. Only a few of the different embodiments are implicit and explicit in the descriptive matter hereinbefore. It would be virtually impossible to catalogue all of the embodiments. Hence, although this invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of this invention.