Patent Application
20120183422
The present invention relates to a compressor. More particularly, the invention is directed to a compressor including an electric motor and a retainer for maintaining a position of a stator of the electric motor.
Presently known hybrid vehicles utilize a combination of an electric drive motor and an internal combustion engine to power and propel the vehicle. Typically, the hybrid vehicles use an electric air conditioning compressor including a compression mechanism such as a scroll compression mechanism, for example, driven by an electric motor. The electric motor and the compression mechanism are mounted within a housing of the compressor. Packaging of the electric motor and the compression mechanism within the housing requires satisfying numerous design constraints such as weight, size, noise and vibration control, manufacturability, serviceability, and electric isolation. Current electric compressor designs satisfy only a few of the constraints.
The electric motor typically includes two primary components: a stator and a rotor. The stator is typically retained in the housing of the compressor by press-fitting the stator in the housing, attaching the stator to the housing fasteners, or capturing the stator by compressing the housing after installing the stator within the housing. The interface between the housing and the stator requires an accurate angular and axial positioning of the stator, a retention of the stator at low and high temperatures, a minimum stress on laminations of the stator, and an ease of assembly and serviceability.
It would be desirable to develop an electric compressor including a retainer for maintaining a position of a stator of the electric motor which facilitates a satisfaction of the design constraints of the packaging of the compressor and the requirements of the interface between the housing and the stator.
In concordance and agreement with the present invention, an electric compressor including a retainer for maintaining a position of a stator of the electric motor which facilitates a satisfaction of the design constraints of the packaging of the compressor and the requirements of the interface between the housing and the stator, has surprisingly been discovered.
In one embodiment, the compressor comprises: a hollow housing; a compression mechanism disposed in the housing, the compression mechanism receiving a fluid therein to be compressed; an electric motor removably disposed in the housing, the electric motor including a stator and a rotor coupled to the compression mechanism for facilitating a movement of the compression mechanism, wherein the movement of the compression mechanism causes a compression of the fluid therein; and a retainer removably disposed between the stator and the housing, the retainer configured to maintain a position of the stator within the housing and to dampen a noise and a vibration produced by the electric motor.
In another embodiment, the compressor comprises: a hollow housing; a compression mechanism disposed in the housing, the compression mechanism receiving a fluid therein to be compressed; an electric motor removably disposed in the housing, the electric motor including a stator surrounding a rotor, the rotor coupled to the compression mechanism for facilitating a movement of the compression mechanism, wherein the movement of the compression mechanism causes a compression of the fluid therein; and an elastic retainer removably disposed between the stator and the housing, the retainer configured to maintain a position of the stator within the housing and to dampen a noise and a vibration produced by the electric motor.
In another embodiment, the compressor comprises: a hollow housing; a compression mechanism disposed in the housing, the compression mechanism receiving a fluid therein to be compressed; an electric motor removably disposed in the housing, the electric motor including a rotor surrounding a stator, the rotor coupled to the compression mechanism for facilitating a movement of the compression mechanism, wherein the movement of the compression mechanism causes a compression of the fluid therein; and a retainer disposed between the stator and the housing, the retainer configured to maintain a position of the stator within the housing and to dampen a noise and a vibration produced by the electric motor.
The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiment when considered in the light of the accompanying drawings in which:
The following detailed description and appended drawings describe and illustrate an exemplary embodiment of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.
The compressor housing 12 comprises cylindrical portions 20a, 20b, 20c, a first end portion 22, and second end portion 24. An open side 26 of the first end portion 22 is releaseably and hermetically connected to an open side 28 of the cylindrical portion 20c. An open side 32 of the second end portion 24 is releaseably and hermetically connected to an open side 34 of cylindrical portion 20a. It is understood that the cylindrical portions 20a, 20b, 20c and the end portions 22, 24 can be connected by any means as desired such as adhesives, pins, clips, and the like, for example. A cavity 36 formed by the connected portions 24, 20a of the compressor housing 12 houses the electric circuit 18 therein. The electric circuit 18 is electrically connected with an external electric power source (not shown) via a terminal 38 disposed on the compressor housing 12.
In the embodiment shown, the compression mechanism 14 includes a fixed scroll 40 and a moveable scroll 42. The fixed scroll 40 includes an end plate 44 and a spiral element 46 extending laterally outwardly from the end plate 44. The moveable scroll 42 includes an end plate 48 and a spiral element 50 extending laterally outwardly from the end plate 48. The spiral element 46 of the fixed scroll 40 cooperates with the spiral element 50 of moveable scroll 42, which is angularly and radially offset therefrom, to form a plurality of sealed fluid pockets 43.
The end plate 44 of the fixed scroll 40 and the first end portion 22 of the compressor housing 12 define a discharge chamber 52 therebetween. A valved outlet port 54 axially formed through the end plate 44 of the fixed scroll 40 fluidly connects the discharge chamber 52 to a central fluid pocket 56 defined by the scrolls 40, 42. A discharge port (not shown) is formed in the first end portion 22 of the compressor housing 12. The discharge port fluidly connects the discharge chamber 52 to an inlet of another component (not shown) such as a condenser of a heating, ventilating, and air conditioning system, for example.
As illustrated, the moveable scroll 42 is mechanically coupled to the electric motor 16 by a rotatable driveshaft 60. A rotation preventing mechanism 61 is disposed between the cylindrical portion 20b of the compressor housing 12 and a face of the end plate 48 of the moveable scroll 42 opposite the spiral element 50. The rotation preventing mechanism 62 includes a ring-shaped member 104 having a central opening 105 formed therein and a plurality of bearing members 106. During a rotational movement of the driveshaft 60, the moveable scroll 42 is caused to revolve. As the moveable scroll 42 revolves, the bearing members 106 cooperate with the ring-shaped member 104 to militate against a rotational movement of the moveable scroll 42 and facilitate an orbital movement thereof.
A first end 62 of the driveshaft 60 is supported by a bearing 63 seated adjacent an annular shoulder 64 formed in an inner surface of the cylindrical portion 20b of the compressor housing 12. A second end 65 of the driveshaft 60 is disposed in a first cavity 66 formed by an annular hub 67. The annular hub 67 extends laterally outwardly from an interior wall 68 of the cylindrical portion 20a of the compressor housing 12. An end portion 96 of the annular hub 67 includes an inner annular shoulder 69 and an outer annular shoulder 97 formed therein. A bearing 70 for supporting the driveshaft 60 in the first cavity 66 is seated adjacent the inner annular shoulder 69 of the end portion 96 of the annular hub 67.
The driveshaft 60 includes an axial bore 71 extending therethrough. The axial bore 71 fluidly connects a second cavity 73 formed in the compressor housing 12 to the first cavity 66. An aperture 72 formed in the annular hub 67 fluidly connects the first cavity 66 to a suction chamber 74. The suction chamber 74 shown is formed by the interior wall 68 and an outer peripheral wall 76 of the cylindrical portion 20a of the compressor housing 12. A suction port 78 is formed in the outer peripheral wall 76 of the cylindrical portion 20a of the compressor housing 12. The suction port 76 fluidly connects the suction chamber 74 to an outlet of another component (not shown) such as an evaporator of a heating, ventilating, and air conditioning system, for example.
The electric motor 16 includes a rotor 80 and a stator 82. In the embodiment shown, the rotor 80 is generally campanular shaped having a substantially closed end 83 and a substantially open end 85. The closed end 83 includes an aperture 84 formed therein and a neck portion 87 circumscribing and drivingly connected to the driveshaft 60. The open end 85 of the rotor 80 receives the stator 82 therein, wherein an outer peripheral surface 86 of the stator 82 is surrounded by the rotor 80. An air gap 88 is formed between the rotor 80 and the outer peripheral surface 86 of the stator 82 to permit rotational movement of the rotor 80 around the stator 82. Windings 89 of the stator 82 are in electrical communication with the electric circuit 18 via a wiring harness (not shown) extending outwardly from a coil end of the stator 82 adjacent the open end 85 of the rotor 80.
The stator 82 is removeably positioned on the annular hub 67 of the cylindrical portion 20a of the compressor housing 12. As illustrated in
The retainer 100 is configured to maintain the axial and radial position of the stator 82 within the compressor housing 12 without requiring additional assembly means or processes such as fasteners, a press-fitting process, a compression of the compressor housing 12 process, and the like, for example. The retainer 100 is also configured to permit the electric motor 16 to be easily installed in the compressor housing 12, removed from the compressor housing 12, or replaced by another electric motor. The retainer 100 can be any retainer as desired such as a tolerance ring, a bushing, a sleeve, and the like, for example. It is understood that the retainer 100 can be integrally formed with the annular hub 67 of the compressor housing 12 if desired. The retainer 100 can be tuned to dampen noise and vibration frequencies produced by the electric motor 16. The retainer 100 shown is tuned by modifying physical properties of the retainer 100 such as a material composition, a thickness, a width, and a shape and configuration thereof, for example. It is understood that the annular hub 67 can also be tuned to dampen noise and vibration frequencies of the electric motor 16 such as by modifying physical properties of the annular hub 67 such as a diameter thereof, for example.
During operation of the compressor 10, a fluid such as a refrigerant gas, for example, flows from an external fluid source through the suction port 78 into the suction chamber 74 of the compressor 10. A first portion of the fluid in the suction chamber 74 flows through the aperture 72 formed in the annular hub 67 into the first cavity 66. The first portion of the fluid then flows from the first cavity 66 into and through the bore 71 of the driveshaft 60 into the second cavity 73. A second portion of the fluid in the suction chamber 74 flows through the aperture 72 formed in the annular hub 67 into the first cavity 66. From the first cavity 66, the second portion of the fluid flows through the bearing 70 and the stator 82, and through the aperture 84 of the closed end 83 of the rotor 80. After flowing through the aperture 84, the second portion of the fluid then flows through the bearing 63 and into the second cavity 73. A third portion of the fluid in the suction chamber 74 flows around an outside of the electric motor 16 through the bearing 63 and into the second cavity 73. All portions of the fluid in the second cavity 73 then flow through the rotation preventing mechanism 161 via the central opening 105 of the ring-shaped member 104, and into the outer sealed fluid pockets 43 of the compression mechanism 14. Once in the sealed fluid pockets 43, the fluid undergoes a resultant volume reduction and compression, and is caused to flow towards the central fluid pocket 56. Finally, the compressed fluid is discharged through the outlet port 54 into the discharge chamber 52. The fluid then flows from the discharge chamber 52 through the discharge port to an external component.
The compressor housing 112 comprises a cylindrical portion 120, a first end portion 122, and second end portion 124. An open side 126 of the first end portion 122 is releaseably and hermetically connected to a first open side 128 of the cylindrical portion 120. An open side 132 of the second end portion 124 is releaseably and hermetically connected to a second open side 134 of the cylindrical portion 120. It is understood that the cylindrical portion 120 and the end portions 122, 124 can be connected by any means as desired such as adhesives, pins, clips, and the like, for example. A terminal 138 for controlling and providing electrical communication to the electric motor 116 is disposed in the second end portion 124 of the compressor housing 112. The terminal 138 is in electrical communication with an external electric power source (not shown).
In the embodiment shown, the compression mechanism 114 includes a fixed scroll 140 and a moveable scroll 142. The fixed scroll 140 includes a spiral element 146 extending laterally outwardly therefrom. The moveable scroll 142 includes an end plate 148 and a spiral element 150 extending laterally outwardly from the end plate 148. The spiral element 146 of the fixed scroll 140 cooperates with the spiral element 150 of moveable scroll 142, which is angularly and radially offset therefrom, to form a plurality of sealed fluid pockets 143.
The fixed scroll 140 and the first end portion 122 of the compressor housing 112 define a discharge chamber 152 therebetween. A valved outlet port (not shown) axially formed through the fixed scroll 140 fluidly connects the discharge chamber 152 to a central fluid pocket (not shown) defined by the scrolls 140, 142. A discharge port (not shown) is formed in the first end portion 122 of the compressor housing 112. The discharge port fluidly connects the discharge chamber 152 to an inlet of another component (not shown) such as a condenser of a heating, ventilating, and air conditioning system, for example.
As illustrated, the moveable scroll 142 is mechanically coupled to the electric motor 116 by a rotatable driveshaft 160. A rotation preventing mechanism 161 is disposed between the cylindrical portion 120 of the compressor housing 112 and a face of the end plate 148 of the moveable scroll 142 opposite the spiral element 150. The rotation preventing mechanism 161 includes a ring-shaped member 204 having a central opening 205 formed therein and a plurality of bearing members 206. During a rotational movement of the driveshaft 160, the moveable scroll 142 is caused to revolve. As the moveable scroll 142 revolves, the bearing members 206 cooperate with the ring-shaped member 204 to militate against a rotational movement of the moveable scroll 142 and facilitate an orbital movement thereof.
A first end 162 of the driveshaft 160 is supported by a bearing 163 seated adjacent an annular shoulder 164 formed in an inner surface of the cylindrical portion 120 of the compressor housing 112. A second end 165 of the driveshaft 160 is disposed in a first cavity 166 formed by an annular hub 167. The annular hub 167 extends laterally outwardly from an end wall 168 of the second end portion 124 of the compressor housing 112. The annular hub 167 includes an inner annular shoulder 169 formed therein. A bearing 170 seated adjacent the inner annular shoulder 169 of the annular hub 167 supports the driveshaft 160 in the first cavity 166.
The driveshaft 160 includes an axial bore 171 extending therethrough. The axial bore 171 fluidly connects a second cavity 173 formed in the cylindrical portion 120 to the first cavity 166. An aperture 172 formed in the annular hub 167 fluidly connects the first cavity 166 to a suction chamber 174. The suction chamber 174 shown is formed by the end wall 168 and an outer peripheral wall 176 of the second end portion 124 of the compressor housing 112. A suction port 178 is formed in the outer peripheral wall 176 of the second end portion 124 of the compressor housing 112. The suction port 178 fluidly connects the suction chamber 174 to an outlet of another component (not shown) such as an evaporator of a heating, ventilating, and air conditioning system, for example.
The electric motor 116 includes a rotor 180 and a stator 182. In the embodiment shown, the rotor 180 is generally annular shaped circumscribing and drivingly connected to the driveshaft 160. The rotor 180 is received in a central passage of the annular-shaped stator 182, wherein the stator 182 surrounds an outer peripheral surface of the rotor 180. An air gap 188 is formed between the rotor 180 and the stator 182 to permit rotational movement of the rotor 180 within the central passage of the stator 182. Windings 189 of the stator 182 are in electrical communication with the terminal 138 via a wiring harness (not shown) extending outwardly from a coil end of the stator 182.
The stator 182 is removeably positioned between a shoulder 190 formed in an inner peripheral surface 192 of the second end portion 124 of the compressor housing 112 and an annular shoulder 194 formed in the open side 134 of the cylindrical portion 120 of the compressor housing 112. As illustrated in
As shown in
The retainer 200 is configured to maintain the axial and radial position of the stator 182 within the compressor housing 112 without requiring additional assembly means or processes such as fasteners, a press-fitting process, a compression of the compressor housing 112 process, and the like, for example. The retainer 200 is also configured to permit the electric motor 116 to be easily installed in the compressor housing 112, removed from the compressor housing 112, or replaced by another electric motor. The retainer 200 can be any retainer as desired such as a bushing, a sleeve, and the like, for example. It is understood that the retainer 200 can be integrally formed with the second end portion 124 of the compressor housing 112 if desired. The retainer 200 can be tuned to dampen noise and vibration frequencies produced by the electric motor 116. The retainer 200 shown is tuned by modifying physical properties of the retainer 200 such as a material composition, a thickness, a width, and a shape and configuration thereof, for example.
During operation of the compressor 100, a fluid such as a refrigerant gas, for example, flows from an external fluid source through the suction port 178 into the suction chamber 174 of the compressor 110. A first portion of the fluid flows through the aperture 172 formed in the annular hub 167 into the first cavity 166. The first portion of the fluid then flows from the first cavity 166 into and through the bore 171 of the driveshaft 160 into the second cavity 173. A second portion of the fluid in the suction chamber 174 flows through the central passage of the stator 182 and around the rotor 180 of the electric motor 116. The second portion of the fluid in the central passage of the stator 182 then flows through the bearing 163 and into the second cavity 173. Both of the portions of the fluid in the second cavity 173 then flow through the rotation preventing mechanism 161 via the central opening 205 of the ring-shaped member 204, and into the outer sealed fluid pockets 143 of the compression mechanism 114. Once in the sealed fluid pockets 143, the fluid undergoes a resultant volume reduction and compression, and is caused to flow towards the central fluid pocket. Finally, the compressed fluid is discharged through the outlet port into the discharge chamber 152. The fluid then flows from the discharge chamber 152 through the discharge port to an external component.
From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, make various changes and modifications to the invention to adapt it to various usages and conditions.
