CA2476741A1

CA2476741A1 - Compact rotary compressor

Info

Publication number: CA2476741A1
Application number: CA002476741A
Authority: CA
Inventors: Nelik I. Dreiman; Rick L. Bunch
Original assignee: Individual
Current assignee: Tecumseh Products Co
Priority date: 2003-08-07
Filing date: 2004-08-05
Publication date: 2005-02-07
Also published as: JP2005054803A; US20050031465A1

Abstract

A compact rotary compressor having a motor with a stator and a rotor wherein the rotor includes an integrally formed part defining an internal compression chamber and an integrally formed vane extending radially inwardly within the compression chamber. A roller is rotatably mounted and eccentrically disposed within the compression chamber with the vane being engaged with the roller whereby rotation of the rotor also rotates the roller. The rotor and roller may each be mounted on a stationary shaft. End plates located on the opposite axial ends of the rotor seal the compression chamber and one of the ends plates may be rotatably mounted on a stationary support structure. One of the end plates may also include a discharge valve assembly and noise attenuation chamber as part of a discharge fluid line providing communication between the compression chamber and a passageway located within the stationary shaft.

Description

COMPACT ROTARY COMPRESSOR
BACKGROUND OF THE INVENTION
1. Field of the Invention.
[0001] The present invention relates to a rotary compressor having a compact design wherein the compression chamber is defined by the rotor of the motor driving the compressor.

2. Description of the Related Art, [0002] Rotary compressors typically include a housing in which a motor and a compression mechanism are mounted being operably connected by a drive shaft. Rotary type compression mechanisms typically include a roller disposed about an eccentric portion of a shaft. The roller is located in a cylinder block that defines a cylindrical compression space. At least one vane extends between the roller and the outer wall of the comprf;ssion chamber to divide the compression chamber into a plurality of compression pockets. The roller is eccentrically located within the compression chamber and, as the shaft rotates, the compression pockets become progressively smaller thereby compressing a refrigerant or other fluid disposed therein. Oftentimes, the vane is biased into contact with either the wall of the compression chamber or the roller by a spring. Other configurations of rotary compressors are also known.
SUMMARY OF THE INVENTION

[0003] The present invention provides a compact rotary compressor in which the rotor of the motor includes a single integral part that also defines an internal compression chamber and includes an integrally formed vane extending radially inwardly into the compression chamber.

[0004] The present invention comprises, in one form thereof, a rotary compressor for compressing a fluid that includes a motor having a stator and a rotor. The rotor includes ar integrally formed part defining an internal compression chamber and an integrally formed vane extending radially inwardly within the compression chamber. A roller is rotatably mounted and eccentrically disposed within the compression chamber. The vane is engaged with the roller wherein rotation of the rotor rotates the roller and thereby compresses the fluid within the compression chamber.

[0005] The integrally formed rotor part may also include a radially outer surface having a plurality of permanent magnets mounted thereon. Further, the roller may define a recess having a bushing mounted therein, wherein the bushing defines a radially extending slot with the vane being slidably disposed within the slot. The roller may be mounted on a stationary shaft wherein the shaft defines an internal passageway in fluid communication with the compression chamber.

[0006] The compressor may also include first and second end plates disposed at opposite axial ends of the compression chamber. At least one of the end plates may define a fluid passageway providing fluid communication between the internal passageway of the shaft and the compression chamber. The shaft extends through one of the end plates. In some embodiments, the shaft may extend through only one of the end plates and with the other end plate being rotatably mounted on a stationary support structure. The stator circumscribes the rotor, the compression chamber disposed therein and the first and second end plates.

[0007] One of the end plates disposed at an end of the compression chamber may define a discharge fluid line having a discharge valve cavity in fluid communication with the compression chamber and a discharge valve member disposed within the discharge valve cavity and controlling fluid flow from the compression chamber through the discharge valve cavity. The end plate may also further define a noise attenuation chamber in fluid communication with the discharge fluid line.

[0008] The present invention comprises, in another form thereof, a rotary compressor for compressing a fluid that includes a housing and a motor mounted in the housing. The motor has a stator and a rotor with the stator circumscribing the rotor. The rotor defines a rotational axis and includes an integrally formed part defining an internal compression chamber and an integrally formed vane extending radially inwardly within said compression chamber.
Opposite axial ends of the rotor define first and second rotor faces respectively. A first end plate is secured to the first rotor face and a second end plate is secured to the second rotor face. A stationary shaft is mounted in the housing and extends through at least one of the end plates and is at least partially disposed within the compression chamber. A
roller is rotatably mounted on the shaft eccentric wherein the roller is rotatable about an axis spaced from the rotational axis of the rotor. The vane is engaged with the roller wherein rotation of the rotor rotates the roller on the shaft and thereby compresses the fluid within the compression chamber.

[0009] An advantage of the present invention is that it provides a compact rotary compressor having relatively high reliability with reduced vibrations and noise.
BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above mentioned and other features and objects of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
Figure 1 is a sectional view of a compact rotary compressor in accordance with the present invention.
Figure 2 is an enlarged fragmentary view of the indicated portion of Figure 1:
Figure 3 is a sectional view of the compression mechanism of the compressor of Figure 1 showing a first position.
Figure 4 is a sectional view of the compression mechanism of the compressor of Figure 1 showing a second position.
Figure 5 is a top plan view of the inner plate of the compressor.
Figure 6 is a sectional view of the inner plate of Figure S taken along line 6-6.

[0011] Corresponding reference characters indicate corresponding parts throughout the several views. Although the exemplification set out herein illustrates an embodiment of the invention, in one form, the embodiment disclosed below is not intended to be exhaustive or to be construed as limiting the scope of the invention to the precise form disclosed.
DESCRIPTION OF THE PRESENT INVENTION

[0012] Referring now to the drawings and particularly to Figure l, there is shown a compact rotary compressor 10. Compressor 10 has hermetically sealed housing 12 including base 14 and body portion 16 which are hermetically sealed by welding, brazing, or the like at location 18. The size of base 14 is greater than the diameter of cylindrical body portion 16 to provide flange 20 having apertures 22 therein for mounting compressor 10.
Compressor 10 is illustrated as being in a substantially horizontal orientation however, compressors in accordance with the present invention may also be vertically orientated.

[0013] Compressor l0,includes electric motor 24 having stator 26. and rotor 28 which defines a portion of compression mechanism 30 provided for compressing refrigerant from a _3_ low pressure to a higher pressure for use in a refrigeration system, for example. Stator 26, having coil assembly 32, is rigidly mounted and circumscribes rotor 28.
Extending through rotor 28 is stationary shaft 34 which is fixedly mounted at end 36 in aperture 38 centrally formed in body portion 16 of housing 12 by welding, brazing, or the like (Figures 1 arid 2).
In the illustrated embodiment, weld 40 secures shaft 34 to housing 12.

[0014) Refernng to Figures 3 and 4, a plurality of pockets 41 are formed in the outer radial surface of rotor 28 in which permanent magnets 42 are mounted by any suitable method including the use of adhesives, for example. Rotor 28 is circumscribed by lamination stack 44 of stator 26 (Figure 1) and, during operation of compressor 10, stator 26 generates a rotating electromagnetic field to rotationally drive rotor 28 having permanent magnets 42 mounted thereon. Rotor 28 also defines an internal compression chamber 52. In the illustrated embodiment, rotor 28 is integrally formed from a solid metal material such as steel, powder metal, ductile iron, or the like in the general shape of an annular ring. The rotor may be manufactured using any suitable method including electric discharge machining (EDM). By using a solid integral part to form rotor 28, no lining is required for internal compression chamber 52 and the rotor may also include an intel,~ral vane 54 that extends radially inwardly within compression chamber 52 to engage roller 50 as discussed in greater detail below.

[0015) Stationary shaft 34 is formed from any suitable metal material including steel, powder metal, ductile iron, or the like by any conventional method including machining, for example. Referring to Figure l, an eccentric portion 48 is integrally formed on shaft 34 and is located within compression chamber 52 defined by rotor 28. Roller 50 forms a part of compression mechanism 30 and is rotatably mounted on eccentric 48. Referring to Figures 3 and 4, vane 54 is integrally formed with rotor 28 and extends radially inwardly from the inner radial surface of rotor 28 that defines compression chamber 52. Vane 54 engages roller 50 and, together with roller 50 divides compression chamber 52 into variable-volume, crescent shaped compression pockets 56.

[0016) Referring to Figures 3 and 4, in order to allow for the relative sliding movement between vane 54 which extends radially inwardly from cylinder block portion 46 of rotor 2 and roller 50, roller 50 is provided with cylindrical aperture 58 extending longitudinally through roller 50 adjacent the outer periphery thereof and defining an opening in the outer radial surface of roller 50. Guide bushing 60 is mounted in aperture 58 and has a longitudinally extending slot 62 formed therein to slidably receive vane 54 such that as rotor 28 rotates, vane 54 reciprocatingly slides within slot 62 as roller 50 rotates on eccentric portion 48 and moves toward and away from the compression chamber wall adjacent vane 54. Bushing 60 may also rotate within aperture 58 to allow for change in angular position of vane 54 with respect to aperture 58 as rotor 24 and roller 50 are rotated.
Similarly, aperture 58 has a radially outer opening that is sufficiently larget,to allow for this relative angular movement of vane 54 during operation of the compressor. In the illustrated embodiment, bushing 60 is a two piece bushing, however, alternative embodiments may employ a single piece bushing wherein an interconnecting web of material extends between the two halves of the bushing through a portion of space 130 and is sufficiently thin to avoid interfering with the reciprocation of vane 54 within slot 62.

[0017] Guide bushing 60 is made from a material with suitable antifriction properties. In the illustrated embodiment, bushing 60 is formed using Vespel SP-21, a material commercially available from E.I. du Pont de Nemours and Company, and which facililtates the reduction of frictional losses caused by sliding movement of vane 54 in slot 62 and relative oscillating movement of bushing 60 within aperture 58 of roller 50.
The use of a guide bushing 60 from a material with good antifriction properties facilitates the reduction of wear of the surfaces of roller 50, vane 54, and guide bushing 60 that are in moving contact to thereby improve the longevity and reliability of the compressor.

[0018] As discussed above, vane 54 is integrally formed with the cylinder block portion 46 of rotor 28 and the use of bushing 60 together with such an integrally funned vane, eliminates the need for a vane spring to press the vane against the roller. The use of bushing 60 to slidably receive vane 54 instead of a spring biased vane, may also reduce the frictional resistance to created by the vane during operation of the compressor. The relatively minimal frictional losses caused by vane 54 facilitates the minimization of power losses due to friction. The use of an integral vane that is slidably received within bushing 60 also facilitates the reduction of refrigerant vapor leakage across the burner formed by vane 54 between a relatively high pressure compression pocket to a relatively low pressure compression pocket during operation of the compressor. The reduced frictional losses and refrigerant leakage facilitate the efficient and reliable operation of the compressor. The use of an integral vane 54 also facilitates the reduction of parts needed to manufacture compressor 10 thereby simplifying and facilitating the cost efficient manufacture of compressor 10.

[0019] Referring to Figures 1, 5, and 6, compression mechanism 30 also includes inner plate 64 is located in adjacent contact with upper axial end surface 66 of rotor 28 to partially define and seal compression chamber 52. As shown in Figures 5 and 6, a plurality of fluid passages are formed in inner plate 64 to define a portion of the discharge line which is further described below. Inner plate 64 is provided with central aperture 68 through which shaft 34 extends. Positioned in adjacent contact with the opposite surface of inner plate 64 is outer plate 70 also having a central aperture 72 through which shaft 34 extends.
Together plates 64 and 70 define a first end plate assembly. Although the illustrated embodiment employs two plates, i.e., plates 64, 70 to define the first end plate, the first end plate is not limited to a two piece construction. Second end plate 74 is positioned in adjacent contact with the lower axial end surface 76 of rotor 28 and partially defines and seals compression chamber 52.
Cylindrical protrusion 78 extends outwardly from the lower surface of plate 74 and is received in upstanding member 80. Second end plate is rotatably mounted on the stationary support defined by member 80 via bearing 88. A thrust bearing 89 is also located between member 80 and second plate 74. The first end plate, i.e., inner plate 64 and outer plate 70, rotor 28 and second plate 74 are secured together to define compression chamber 52. In the illustrated embodiment, a plurality of bolts extend through apertures in outer plate 70, inner plate 64, rotor 28, and second end plate 74 to secure these components to one another.
Alternative embodiments may employ alternative methods of securing these components together such as welding.

[0020] Compression assembly 30 is rotatably mounted on shaft 34 by a plurality of bearings 82, 84, and 86 which are press-fit into the apertures defined by outer plate 70 and inner plate 64, and the inner diameter of roller 50, respectively. Bearing 88 is press-fit onto protrusion 78 to rotatably support second end plate 74 by rotatably mounting protrusion 78 in upstanding member 80. When the compressor is operating and rotor 28 is rotated, bearings 82, 84, 86, and 88 rotatably support compression assembly 30 as it is rotatably driven about stationary shaft 34. As best seen in Figures l, 3 and 4, bearings 82, 84 and 88 which rotatably support rotor 24 and the first and second end plates enclosing compression chamber 52 are centered on rotor axis 24a and bearing 86 rotatably supporting xoller 50 is centered o:.
roller axis 50a defined by eccentric portion 48 of shaft 34. Axes 24a and SOa are spaced apart whereby roller 50 will form a line, or area, of contact with the inner radial surface of rotor 24 that defines compression chamber 52 that progressively travels along the circumference of the inner radial surface of rotor 24 as rotor 24 and roller 50 rotate about their respective axes.

The relative rotation of rotor 24 and compression chamber 52 and roller 50 with respect to shaft 34 and axes 24a and SOa defines compression pockets for compressing refrigerant in a manner typical for rotary compressors that is well known in the art.

[0021] Bearings 82, 84, 86, 88 and 89 may be formed from a polyamide material having relatively low coefficients of static and kinetic friction such as Vespel SP-21. Another beneficial characteristic associated with polyamide is that it derr~onstrates thermal stability over a relatively broad temperature range. For example, polyamide bushings may be capable of withstanding a bearing pressure of approximately 300,000 lb ft/inz and a contact temperature of 740°F. For the optimum performance of the bushings and to avoid overheating, bushings 82, 84, 86 and 88 advantageously have a length to inside diameter ratio of no more than 3:2.

[0022] Compressor 10 as described above utilizes a bushing 60 and bearings 82, 84, 86 and 88 that do not require lubrication. While the above-described embodiment is equipped with self lubricating bushings and bearings, alternative embodiments may utilize alternative bushings and bearings, e.g., needle or ball-type bearings and a conventional oil sump and pump for supplying lubricating oil to the bearings.

[0023] 'Assembly of compressor 10 may advantageously include first assembling compression assembly 30. Initially, roller 50, having guide bushing 60 press fit therein is located in compression space 52 such that vane 54 engages slot 62 and rotor 28 is positioned in abutting contact with second end plate 74. Bushing 86 is press fit within cylindrical aperture 58 of roller 50 and shaft 34 is inserted within bushing 86 to thereby rotationally engage roller 50 and shaft 34. Inner plate 64 and outer plate 70, having the respective bearings 82 and 84 assembled therev~rith, are then positioned on shaft 34 and fasteners are used to secure the compression chamber components together. Also mounted to shaft 34 is compression kit 89 (Figures 1 and 2) which is provided to secure the relative position of compression mechanism 30 with respect to housing 12 and stator 26. Compression kit 89 axially biases compression mechanism 30 towards upstanding member 80:
Compression kit 89 is shown in Figure 2 and includes wave spring 90 which applies pressure to steel washer 92 facing upper surface 94 of bearing 82. Retaining ring 96 is located on the opposite side of wave spring 90 and has a radially inner portion 97 that engages annular groove 99 formed in shaft 34. Suitable wave springs are commercially available from the Smalley Steel Ring Company located in Lake Zurich, Illinois. The assembled compression mechanism 30 is then mounted in housing body portion 16 with end 36 of shaft 34 extending through aperture 38.
_7_ Shaft 34 is secured to body portion 16 of housing 12 with weld 40. Also located in housing body portion 16 is inlet 98 through which suction pressure refrigerant enters motor cavity 100. Stator 26 is shrink fitted into housing body portion 16 and is electrically coupled via wire 102 to terminal assembly 104 also mounted in the housing body portion 16.
Compression mechanism 30 is positioned within housing body portion 16 such that rotor 28 is aligned with stator 26. The assembled compression mechanism and housing body portion is then mounted to housing base 14 with bearing 88 mounted on protrusion 78 being received in upstanding portion 80. Housing body portion 16 is then welded to housing base 14 at seam 18. By positioning compression chamber 52 within rotor 24 and circumscribing rotor 24, compression chamber 52 and end plates 64, 70 and 74 with stator 26 the overall assembled axial extending length of compressor 10 is relatively limited and thereby provides a compact overall design that facilitates. the flexible positioning of the compressor.

[0024] The compact arrangement provided by the present invention allows the axial length of the compressor to be reduced to approximately the same axial length of the stator 26.

[0025] During compressor operation, electrical current supplied to stator 26 via terminal assembly 104 creates a magnetic flux which in turn causes rotation of rotor 28. The rotation of rotor 28 drives the rotation of roller 50 about drive shaft 34 through vane 54 which is integrally formed with rotor 28 and engaged with roller 50. Referring to Figures 3 and 4, as rotor 28 and roller ~0 rotate, vane 54 slides within slot 62 in bushing 60 and the crescent shaped compression pockets 56 defined within compression chamber 52 become progressively smaller as they approach discharge port 140. After passing discharge port 140, compression pockets 56 enlarge and refrigerant is drawn into the compression pockets 56 through a suction port (not shown).

[0026] The refrigerant flows through a pathway best seen in Figures l, 5, and 6. The pathway is partially defined by a plurality of passages located in inner plate 64 and provides for the intake and discharge of refrigerant fluid by compression mechanism 30.
Relatively low pressure refrigerant vapor, i.e., suction pressure refrigerant, is introduced into the motor cavity 100 through inlet 98. Thus, compressor 10 is a low side compressor in which motor cavity 100 is filled with suction pressure refrigerant. The suction pressure refrigerant is at a lower temperature than the compressed refrigerant and facilitates the cooling of the motor.
The present invention is not limited to low side compressors, however, and alternative embodiments may employ a variety of configurations including high side compressor designs wherein the motor cavity is filled with discharge pressure refrigerant.
_g_ [0027] In the illustrated embodiment, the refrigerant passes through a suction port (not shown) in inner plate 64 and is introduced into a relatively large compression pocket 56 defined within compression chamber 52. The suction port is located in inner plate 64 such that discharge valve 106 and the suction poxt are in communication with separate compression pockets 56 throughout an entire 360 degree rotation of rotor 28 and roller 50 about shaft 34. After refrigerant is drawn into a compression pocket 56, rotation of rotor 28 and roller 50 about shaft 34 causes the progressive reduction in size of the compression pocket and the compression of the refrigerant vapor disposed therein, when the compression pocket is in fluid communication with discharge valve assembly 106 and the pressure within the compression pocket is sufficient to open the discharge valve assembly 106, compressed refrigerant is discharged from compression chamber 52 through discharge port 140 and the discharge valve assembly 106 disposed within discharge valve cavity 12 formed in plate 64 as best seen with reference to Figures 1, 5 and 6.

[0028] The discharge valve assembly includes a valve seat body 142 defining discharge port 140 in fluid communication with compression chamber 52 and a spherical valve member 144 biased into engagement with a valve seat defined by body 142 by spring 146 to thereby seal the discharge port. A retaining ring 148 secures spring 146 within valve seat body 142.
When the fluid pressure within the discharge pocket 56 that is in fluid communication with the discharge port 140 exceeds the pressure necessary to overcome the biasing force of spring 146, the valve will be forced open and refrigerant will be discharged from compression chamber 52 through discharge port 140. The discharged refrigerant is then communicated through discharge cavity 112 to fluid channel 110. Fluid channel 110 defines a passageway to the circular channel forming discharge muffler 108. Discharge muffler 108, and passages 110 and 120, are defined by recesses in inner plate 64 and the sealing engagement of outer plate 70 with inner plate 64 as best seen in Figure 1. Muffler 108 has two branches 116 and 118 (Figure 5) each leading to channel 120 which is in continuous fluid communication with peripheral groove 122 (Figure 1) on shaft 34. Groove 122 is, in turn, in fluid communication with one or more radial channels 124 formed in shaft 34. As best seen in Figure 1, radial channel 124 communicates discharged refrigerant to passage 126 extending longitudinally through shaft 34 toward discharge fitting 128. The compressed refrigerant is discharged from compressor 10 through discharge fitting 128 to a system that utilizes compressed fluid such as a refrigeration system or heat pump system.

[0029] The configuration of discharge muffler passage 108 helps to control noise and reduces the flow velocity. By providing a greater cross sectional area than the discharge port and channel 110, passage 108 reduces the flow velocity of the discharged fluid which facilitates the reduction of noise. Additionally, during operation of the illustrated compressor, compressed refrigerant vapors are discharged through valve 106 on a periodic basis as the individual compression pockets 56 reach the necessary pressure to open valve 106. The periodic discharge of vapors through valve 106 may create a pressure wave within the discharged vapors. By splitting the discharge flow into two separate channels, i.e., branches 116 and 118, which then meet before the compressed fluid enters radial channel 120, the pressure waves present in the two separate channels meet and, if they are out of phase, at least partially destructively interfere with each other, thereby reducing the amplitude of the pressure wave and the vibrations and resulting noise that may be created thereby. By altering the respective lengths of branches 116 and 118 the wavelength of the pressure waves subject to the most destructive interference can also be altered. In the illustrated embodiment, channel 120 is located diametrically opposite channel 110 and branches 116 and 118 have similar lengths, however, in alternative embodiments, it may be advantageous to locate channel 120 such that branches 116 and 118 have unequal lengths to enhance the destructive interference of pressure waves having a selected wavelength.
Dashed lines in Figure 5 illustrate an alternative location 120a for a channel providing communication between passage 108 and groove 122 that defines branches having unequal lengths. As described above, passage 108 acts as a noise attenuation chamber by both reducing the velocity of the discharged refrigerant conveyed therethrough and by promoting the destructive interference of the pressure waves conveyed by the discharged refrigerant.

[0030] Referring to Figures 3 and 4, the radial slot 62 in roller 50 has a small space 130 located between the distal end 132 of vane 54 and the surface of the roller 50 opposite distal end 132. As vane 54 reciprocates within slot 62, the volume of space 130 is alternatively reduced and expanded. If space 130 is well sealed and without an outlet, the vapor within space 130 would be compressed as vane 54 moves further into slot 62 and expanded as vane 54 move radially ouwardly within slot 62 thereby performing work on the gas located it space 130 without obtaining any benefit therefrom and degrading the efficiency of compressor 10. If space 130 is not well sealed with respect to the compression pockets 56 located on opposite sides of vane 54, as vane 54 moves radially outwardly within slot 62, vapor from the relatively high pressure adjacent compression pocket might be drawn into space 130 and then expelled to the relatively low pressure adjacent compression pocket as vane 54 subsequently moves further into slot 62 thereby leading to the reexpansion of the vapor, loss of volumetric efficiency and a possible increase in undesirable noise.

[0031] To inhibit the loss of efficiency and reverse flow as a result of the interaction of vane 54 and slot 62, bushing 60 engages opposite sides of vane 54 and a communication passage 134 (Figures 1, 5, and 6) is formed in the inner plate 64 to connect space 130 with the discharge muffler passage 108. Thus, as vane 54 moves further into slot 62, vapors within space 130 may be communicated to passage 108 and, as vane 54 moves radially outwardly within slot 62, vapor at discharge pressure may be communicated to space 130 through passage 134.

[0032] While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles.

Claims

1. A rotary compressor for compressing a fluid comprising:
a motor having a stator and a rotor;
wherein said rotor includes an integrally formed part defining an internal compression chamber and an integrally formed vane extending radially inwardly within said compression chamber; and a roller rotatably mounted and eccentrically disposed within said compression chamber, said vane engaged with said roller wherein rotation of said rotor rotates said roller and thereby compresses the fluid within said compression chamber.

2. The rotary compressor of claim 1 wherein said integrally formed part includes a radially outer surface having a plurality of permanent magnets mounted thereon.

3. The rotary compressor of claim 1 wherein said roller defines a recess having a bushing mounted therein, said bushing defining a radially extending slot, said pane being slidably disposed within said slot.

4. The rotary compressor of claim 1 further comprising first and second end plates disposed at opposite axial ends of said compression chamber.

5. The rotary compressor of claim 1 wherein said roller is mounted on a stationary shaft, said shaft defining an internal passageway in fluid communication with said compression chamber.

6. The rotary compressor of claim 5 wherein at least one of said end plates defines a fluid passageway providing fluid communication between said internal passageway of said shaft and said compression chamber.

7. The rotary compressor of claim 1 further comprising first and second end plates disposed at opposite ends of said compression chamber and wherein said roller is mounted on a stationary shaft, said shaft extending through at least one of said end plates.

8. The rotary compressor of claim 7 wherein said shaft extends through only said first end plate and said second end plate is rotatably mounted on a stationary support structure.

9. The rotary compressor of claim 1 further comprising first and second end plates disposed at opposite ends of said compression chamber and wherein said stator circumscribes said rotor, said compression chamber disposed therein and said first and second end plates.

10. The rotary compressor of claim 1 further comprising at least one end plate disposed at an end of said compression chamber, said at least one end plate defining a discharge fluid line having a discharge valve cavity in fluid communication with said compression chamber; said at least one end plate including a discharge valve member disposed within said discharge valve cavity and controlling fluid flow from said compression chamber through said discharge valve cavity.

11. The rotary compressor of claim 10 wherein said end plate further defines a noise attenuation chamber in fluid communication with said discharge fluid line.

12. A rotary compressor for compressing a fluid comprising:
a housing;
a motor mounted in said housing, said motor having a stator and a rotor, said stator circumscribing said rotor, said rotor defining a rotational axis and including an integrally formed part defining an internal compression chamber and an integrally formed vane extending radially inwardly within said compression chamber, opposite axial ends of said rotor defining first and second rotor faces respectively;
a first end plate secured to said first rotor face;
a second end plate secured to said second rotor face;
a stationary drive shaft mounted in said housing and extending through at least one of said end plates and at least partially disposed within said compression chamber; and a roller rotatably mounted on said drive shaft wherein said roller is rotatable about an axis spaced from the rotational axis of said rotor, said vane engaged with said roller wherein rotation of said rotor rotates said roller and thereby compresses the fluid within said compression chamber.

13. The rotary compressor of claim I2 wherein said integrally formed part includes a radially outer surface having a plurality of permanent magnets mounted thereon.

14. The rotary compressor of claim 12 wherein said roller defines a recess having a bushing mounted therein, said bushing defining a radially extending slot, said vane being slidably disposed within said slot.

15. The rotary compressor of claim 12 wherein said shaft defines an internal passageway in fluid communication with said compression chamber.

16. The rotary compressor of claim 15 wherein at least one of said end plates defines a fluid passageway providing fluid communication between said internal passageway of said shaft and said compression chamber.

17. The rotary compressor of claim 12 wherein said shaft extends through only said first end plate and said second end plate is rotatably mounted on a stationary support structure.

18. The rotary compressor of claim 12 wherein said stator circumscribes said compression chamber disposed within said rotor and said first and second end plates.

19. The rotary compressor of claim 12 wherein said first end plate defines a discharge fluid line having a discharge valve cavity in fluid communication with said compression chamber; said first end plate including a discharge valve member disposed within said discharge valve cavity and controlling fluid flow from said compression chamber through said discharge valve cavity.

20. The rotary compressor of claim 19 wherein said first end plate further defines a noise attenuation chamber in fluid communication with said discharge fluid line.