The field relates generally to scroll compressors, and more particularly, to scroll compressors including a subassembly that facilitates installing compressor components (e.g., scrolls, bearing housing, driveshaft) within the compressor as a single unit and aligning the compressor components in the compressor.
Scroll compressors compress refrigerant using a non-orbiting scroll member and an orbiting scroll member that cooperate to form sealed pockets therebetween. During operation of the scroll compressor, motion of the orbiting scroll member relative to the non-orbiting scroll member continuously changes the volume of the sealed pockets to compress refrigerant within.
Scroll compressors typically include one or more bearings which support rotation of a driveshaft and a drive bearing for transmitting rotational motion of the driveshaft to the orbiting motion of the scroll member. The drive bearing is housed in a main bearing housing and provided between a drive coupling of the orbiting scroll member and an eccentric body of the driveshaft. The drive bearing enables the eccentric body to rotate, applying a driving force to the drive coupling, such that the orbiting scroll member will orbit relative to the non-orbiting scroll member to effect compression of a fluid.
During operation, mis-alignment between the main bearing housing and the orbiting and non-orbiting scroll members may create the opportunity for the driveshaft to deflect under applied loads, which may lead to wear of compressor components (e.g., bearings). As demand increases for efficient and reliable operation of the compressor to ensure that the climate-control system in which the compressor is installed is capable of effectively and efficiently providing a cooling and/or heating effect on demand, the tolerances for mis-alignment between the main bearing housing and the scroll members continue to shrink. Furthermore, there is ongoing demand for ways to reduce the opportunity of wear on components, such as bearing assemblies, of the scroll compressor and increase the longevity of the compressor and the climate-control system. Accordingly, a need exists for an improved alignment structure that facilitates reducing the opportunity for mis-alignment between the main bearing housing and scroll members within the scroll compressor.
This background section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
One aspect is a compressor that includes a compressor housing and a compression subassembly installed in the compressor housing. The compressor housing includes a shell defining a first chamber and an end cap defining a second chamber. The compression subassembly includes a support plate positioned in the compressor housing between the shell and the end cap, a non-orbiting scroll attached to the support plate and extending from the support plate into the first chamber, a main bearing housing positioned in the first chamber and attached to the non-orbiting scroll, and an orbiting scroll positioned between the non-orbiting scroll and the main bearing housing. The support plate separates the first chamber and the second chamber and the compression subassembly is supported in the compressor housing by the support plate.
Another aspect is a compression subassembly installable as a single unit in a compressor housing. The compression subassembly includes a support plate for supporting the compression subassembly in the compressor housing. The support plate includes an annular body, a central opening defined in the annular body, and an inner circumferential surface circumscribing the central opening. The compression subassembly also includes a non-orbiting scroll attached to the support plate. The non-orbiting scroll includes a raised portion extending into the central opening of the support plate, the raised portion defining a raised circumferential surface. The raised circumferential surface and the inner circumferential surface of the support plate are in sealing engagement. The compression subassembly also includes a main bearing housing attached to the non-orbiting scroll and an orbiting scroll positioned between the non-orbiting scroll and the main bearing housing.
Another aspect is a method of assembling a compressor. The method includes assembling a compression subassembly by attaching a non-orbiting scroll to a support plate, positioning an orbiting scroll on a surface of a main bearing housing, and attaching the main bearing housing to the non-orbiting scroll such that the orbiting scroll is positioned between the non-orbiting scroll and the main bearing housing. The method also includes installing the compression subassembly as a single unit in a first chamber defined by a shell of a compressor housing by positioning the support plate on the shell such that the compression subassembly is supported in the first chamber by the support plate, positioning an end cap of the compressor housing on the shell such that a second chamber is defined between the end cap and the shell, where the second chamber is separated from the first chamber by the support plate, and attaching the support plate and the end cap to the shell.
Various refinements exist of the features noted in relation to the above-mentioned aspects. Further features may also be incorporated in the above-mentioned aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to any of the illustrated embodiments may be incorporated into any of the above-described aspects, alone or in any combination.
The following figures illustrate various aspects of the disclosure.
Corresponding reference numerals indicate corresponding parts throughout the drawings.
Referring to
The compressor 100 includes an inlet fitting 110 attached to the compressor housing 102 at an inlet opening (not shown) through which working fluid (e.g., refrigerant) enters the at least one sealed cavity formed by the compressor housing 102. In the example compressor 100, the working fluid enters into a first chamber 112 (
The motor assembly 122 (shown schematically in
The driveshaft 128 is rotatably supported within a first bearing housing assembly 206 and second bearing housing assembly 130. The first bearing housing assembly 206 and the second bearing housing assembly 130 are axially displaced and located on opposite sides of the motor assembly 122. The first bearing housing assembly 206 is located proximate the first end 118 of the shell 104 and the second bearing housing assembly 130 is located proximate the second end 120 of the shell 104 (e.g., within the base 108). The driveshaft 128 extends through the first bearing housing assembly 206 and includes an eccentric body 132 extending axially beyond the first bearing housing assembly 206.
The first bearing housing assembly 206 includes a primary bearing 134 (shown in
The compression subassembly 200 is installed in the compressor housing 102. Still referring to
The first bearing housing assembly 206 includes the primary bearing 134 and a main bearing housing 208. The main bearing housing 208 has a generally disk-shaped body 210 that includes a central bore 212 extending between a first annular pocket 214 and a second annular pocket 216. The first annular pocket 214 faces the motor assembly 122 and houses the primary bearing 134. The second annular pocket 216 is axially displaced from the first annular pocket 214 and faces the compression mechanism 204. The second annular pocket 216 is circumscribed by a thrust bearing surface 218 that supports the compression mechanism 204. The main bearing housing 208 also includes sleeve guides or bushings 220 that extend axially from a radial outer portion of the body 210 toward the compression mechanism 204. The bushings 220 define apertures 221 that receive fasteners 222 (e.g., screws or bolts), shown in
The compression mechanism 204 includes an orbiting scroll 226 and a non-orbiting scroll 228. The orbiting scroll 226 includes a generally disk-shaped orbiting plate 230 defining opposing radial surfaces. An orbiting spiral wrap 232 extends axially from one of the radial surfaces of the orbiting plate 230, and the radial surface opposite the orbiting spiral wrap 232 defines a thrust surface 234 that engages the thrust bearing surface 218 of the main bearing housing 208 which supports the orbiting scroll 226. A cylindrical hub 236 extends axially from the thrust surface 234 and is received within the second annular pocket 216 of the main bearing housing 208. The cylindrical hub 236 is aligned with the central bore 212 of the main bearing housing 208. A radial surface 237 defined at an end of the cylindrical hub 236 may be supported by a second thrust bearing surface 239 defined in the second annular pocket 216 and circumscribing the central bore 212. A drive bushing (not shown) may be disposed in the cylindrical hub 236, and receives the eccentric body 132 of the driveshaft 128 that extends through the central bore 212 of the main bearing housing 208. The eccentric body 132 drivingly engages the drive bushing in the cylindrical hub 236 of the orbiting scroll 226, and facilitates transmitting rotational motion of the driveshaft 128 to orbiting motion of the orbiting scroll 226 relative to the main bearing housing 208 and/or the non-orbiting scroll 228. The annular pocket 216 is sized and shaped to enable orbiting movement of the cylindrical hub 236 therein. The bushings 220 of the main body housing 208 are located radially outward from the orbiting plate 230 so as not to limit or prevent orbiting motion of the orbiting scroll 226. The coupling 224 (e.g., an Oldham coupling) may be engaged with the orbiting scroll 226 and the main bearing housing 208 and/or the non-orbiting scroll 228 to limit or prevent relative rotation therebetween.
The non-orbiting scroll 228 includes a non-orbiting body 238 defining opposing radial surfaces 241, 243 and a circumferential edge extending between the radial surfaces 241, 243. A non-orbiting spiral wrap 240 is defined in one of the radial surfaces 241 of the body 238 and faces the orbiting spiral wrap 232. The non-orbiting scroll 228 also includes a raised portion 245 extending axially from the other one of the radial surfaces 243 of the non-orbiting body 238. The raised portion 245 defines an outer radial surface 242 of the non-orbiting scroll 228 raised relative to the radial surface 243 of the body 238. The radial surface 243 of the body 238 may also be referred to as a lower radial surface 243, relative to the outer radial surface 242. The outer radial surface 242 faces the second chamber 116 defined by the end cap 106.
The non-orbiting spiral wrap 240 engages, or meshes, the orbiting spiral wrap 232 of the orbiting scroll 226, defining a series of fluid pockets. Orbiting motion of the orbiting scroll 226 translates to movement of the fluid pockets defined by the spiral wraps 232 and 240, whereby the fluid pockets decrease in volume to compress working fluid in the fluid pockets. During a compression cycle of the compression mechanism 204, the fluid pockets defined by the spiral wraps 232 and 240 decrease in volume as orbiting motion of the orbiting scroll 226 translates to movement of the fluid pockets from a radially outer position (at a suction pressure) to a radially intermediate position (at an intermediate pressure) to a radially inner position (at a discharge pressure).
The non-orbiting scroll 228 includes at least one discharge port 244 extending from the spiral wrap 240, through the non-orbiting body 238 and the raised portion 245, to the outer radial surface 242. Each discharge port 244 is in communication with one of the fluid pockets defined by the spiral wraps 232 and 240 at the radially inner position and allows compressed working fluid (e.g., refrigerant) at the discharge pressure to flow into the second chamber 116 (e.g., a discharge chamber). The non-orbiting scroll 228 also includes at least one intermediate port 246 extending from the spiral wrap 240, through the non-orbiting body 238 and the raised portion 245, to the outer radial surface 242. Each intermediate port 246 is located radially outward from the at least one discharge port 244 and allows communication with one of the fluid pockets defined by the spiral wraps 232 and 240 at the radially intermediate position and/or the radially outer position from the outer radial surface 242. Flow of the working fluid through the intermediate ports 246 from a respective fluid pocket into the second chamber 116 may be regulated by a valve assembly (not shown) located at the outer radial surface 242. For example, a check valve (e.g., a reed valve) may be located at the outer radial surface 242 adjacent an intermediate port 246 to selectively permit or restrict flow of working fluid into the second chamber 116. Additionally and/or alternatively, one or more of the intermediate port(s) 246 may be a sensor port for receiving a sensor (e.g., a temperature sensor or a pressure sensor) for monitoring an operating parameter (e.g., temperature or pressure) within the respective fluid pocket during operation of the compression mechanism 204.
The non-orbiting scroll 228 is positioned over the orbiting scroll 226 and attached to the main bearing housing 208 such that the orbiting scroll 226 is moveably positioned between the non-orbiting scroll 228 and the main bearing housing 208. The orbiting scroll 226 is allowed to move radially between the non-orbiting scroll 228 and the main bearing housing 208, that is, in orbiting motion transmitted by the rotation driveshaft 128. The orbiting scroll 226 may also move axially, or “float,” between the non-orbiting scroll 228 and the main bearing housing 208 during a compression cycle of the compression mechanism 204 to selectively enable or prevent the flow of working fluid at discharge pressure into the first chamber 112 (e.g., a suction chamber) and facilitate balancing pressure in response to a high discharge-to-suction pressure ratio in the compressor 100. For example, the orbiting plate 230 of the orbiting scroll 226 may define a bleed port (not shown) that enables working fluid to flow from one or more fluid pockets of the compression mechanism 204 into a volume of the first chamber 112 defined between the main bearing housing 208 and the orbiting scroll 226. This working fluid may be at a greater pressure (e.g., at intermediate pressure) than the first chamber 112 (e.g., suction pressure), and a pressure differential that exists between the intermediate pressure working fluid and suction pressure in the first chamber 112 may exert a net axial biasing force on the orbiting plate 230, urging the orbiting scroll 226 toward the non-orbiting scroll 228. When the pressure differential dissipates, the axial biasing force on the orbiting scroll 226 ceases and the orbiting scroll 226 moves axially away from the non-orbiting scroll 228. In examples where the orbiting scroll 226 floats between non-orbiting scroll 228 and the main bearing housing 208, the non-orbiting scroll 228 may be fixed within the compressor housing 102 (e.g., by attachment to the support plate 202) such that axial movement of the non-orbiting scroll 228 is limited or inhibited.
The bushings 220 of the main bearing housing 208 engage a flange 248 of the non-orbiting scroll 228 that extends radially outward from the circumferential edge of the non-orbiting body 238 proximate the non-orbiting spiral wrap 240. The flange 248 may be a unitary structure that has a continuous circumferential extent along the circumferential edge of the non-orbiting body 238, or the flange 248 may be discontinuous and formed by two or more discrete flange members. In some examples, the flange 248 is formed by multiple radially extending ears that each correspond to and engage one of the bushings 220 of the main bearing housing 208. The flange 248 may define a diameter that may be approximately equal to the inner diameter D4 (
The flange 248 of the non-orbiting scroll 228 includes holes 249 extending axially through the flange 248. As shown in
The non-orbiting scroll 228 is attached to the support plate 202 which separates the first chamber 112 (e.g., a suction chamber) from the second chamber 116 (e.g., a discharge chamber). The support plate 202 supports the compression subassembly 200 within the compressor housing 102. The support plate 202 is positioned in the compressor housing 102 between the end cap 106 and the shell 104, as shown in
The annular body 250 and the shell 104 also cooperatively seal the first chamber 112 from the second chamber 116 by the attachment between the annular body 250 and the shell 104. In the illustrated embodiment, the annular body 250 of the support plate 202 is solid and does not include openings through which working fluid can flow. As such, the annular body 250 separates the first chamber 112 from the second chamber 116 and maintains a pressure differential between the second chamber 116 and the first chamber 112, which may be suitable in low-side compressor applications (e.g., where the first chamber 112 is a suction chamber and the second chamber 116 is a discharge chamber). In other examples, such as where the compressor 100 is a high-side compressor, the working fluid in the first chamber 112 and the second chamber 116 may be at a same pressure (e.g., discharge pressure), and the annular body 250 may include pass-through features (e.g., holes) that allow working fluid to flow though the annular body between the first chamber 112 and the second chamber 116.
The raised portion 245 of the non-orbiting scroll 228 extends into the central opening 252 defined in the annular body 250 of the support plate 202. The outer radial surface 242 defined by the raised portion 245 is accessible via the central opening 252. As such, the at least one intermediate port 246 in communication with the fluid pockets of the compression mechanism 204 may be accessible through the central opening 252. Advantageously, the intermediate port(s) 246, which, as described above, may be a sensor port and/or may be associated with a valve assembly (e.g., a reed valve) for regulating flow of working fluid therethrough, are accessible without having to remove the support plate 202 and/or otherwise disassemble the compression subassembly 200.
With additional reference to
As shown in
Still referring to
When the compression subassembly 200 is installed in the compressor housing 102, the stop surface 282 of the first flange member 274 is seated on a rim 138 of the shell 104 located at the first end 118. The stop surface 282 and the rim 138 may be shaped (e.g., machined) to provide complementing surfaces (e.g., complementing flat surfaces). The complementing surfaces of the rim 138 and stop surface 282 may facilitate balancing the support plate 202 on the rim 138 and centering the compression subassembly 200 within the compressor housing 102. The stop surface 282 facilitates locating the support plate 202 on the shell 104 and the first flange member 274 enables the support plate 202 to be attached to the rim of the shell 104. The stop surface 282 also facilitates controlling the depth into the shell 104 that the support plate 202 extends, as well as overall alignment of the compression subassembly 200. The first flange member 274 may be attached to the shell 104 using any suitable means to join components. For example, the first flange member 274 may be welded to the shell 104. The connection (e.g., a welded connection) between the first flange member 274 and the shell 104 may suitably create a seal that facilitates limiting or preventing working fluid from leaking between the second chamber 116 and the first chamber 112.
As shown in
When the compression subassembly 200 is installed in the compressor housing 102, the second flange member 276 is received by the rim 138 of the shell 104. The second flange member 276 facilitates centering the support plate 202 on the shell 104. The outer diameter D1 of the second flange member 276 proximate the second radial surface 256 may be approximately equal to an inner diameter D4 of the shell 104 such that the second flange member 276 is press-fit within the shell 104, which may enable the support plate 202 to be more easily centered on the shell 104 for aligning the compression subassembly 200 within the compressor housing 102. The chamfered outer edge 286 at the leading end 284 of the second flange member 276, which provides the reduced outer diameter D2 of the second flange member 276 at the leading end 284, may facilitate piloting the second flange member 276 into the shell 104 before the second flange member 276 engages the shell 104 by press-fit at the outer diameter D1 proximate the second radial surface 256.
Referring again to
In the compression subassembly 300 of
In the compression subassembly 400 of
Still referring to
Referring to
Once the compression subassembly is assembled 502, the compression subassembly may be installed 504 in a first chamber of the compressor housing 102 as a pre-assembled, single unit. For example, the compression subassembly may be installed 504 in the first chamber 112 defined by the shell 104 of the compressor housing 102. Installing 504 the compression subassembly in the compressor housing may include inserting the main bearing housing 208, the orbiting scroll 226, and the non-orbiting scroll 228 into the first chamber 112 and positioning the support plate 202 on the shell 104. The compression subassembly is supported in the first chamber 112 by the support plate 202. For example, the compression subassembly may be suspended from or “hang” from the support plate 202, which is centered and fixedly positioned on the shell 104 to facilitate aligning the compression subassembly within the shell 104. The driveshaft 128 may optionally be inserted into the first chamber 112 and supported by the support plate 202 if the driveshaft 128 is assembled 502 as part of the compression subassembly.
As described above with reference to
With the compression subassembly installed 504 in the first chamber 112, an end cap (e.g., the end cap 106) of the compressor housing 102 may be positioned 506 on the shell 104 such that a second chamber (e.g., the second chamber 116) is defined between the end cap 106 and the shell 104. The support plate 202 is positioned between the end cap 106 and the shell 104 and separates the first chamber and the second chamber. The support plate 202 and the end cap 106 may then be attached 508 to the shell 104, separately or in a single attaching operation. For example, the support plate 202 and the end cap 106 may be attached 508 to the shell 104 by welding, separately or in a single welding operation. Alternatively, one or both the support plate 202 and the end cap 106 may be attached 508 to the rim 138 by another suitable attaching means (e.g., bolts).
When the compressor is assembled by the method 500, including the compression assembly installed 504 in the compressor housing, the main bearing housing 208 and/or the non-orbiting scroll 228 may be press-fit against the shell 104 or may be radially displaced from the shell. Press-fit between the main bearing housing 208 and/or the non-orbiting scroll 228 may not be required for installing 504 the compression subassembly and supporting the compression subassembly within the compressor housing because the support plate 202 attached to the shell 104 facilitates centering and supporting the compression subassembly within the shell 104. Gaps that exist between the shell 104 and the main bearing housing 208 and/or the non-orbiting scroll 228 installed 504 in the compressor housing 102 may result in the fluid cavity 272 being at the same pressure as the first chamber 112 (e.g., suction pressure). Suitably, the seals created by the attachment of the non-orbiting scroll 228 to the support plate 202 and the attachment of the support plate 202 to the shell 104 facilitate limiting or preventing working fluid from flowing directly between the fluid cavity 272 and the second chamber 116, which may be at a different pressure than the fluid cavity (e.g., discharge pressure).
Embodiments described achieve superior results as compared to prior compressors. In particular, the compression subassemblies described herein facilitate installing and aligning compressor components (e.g., scrolls, bearings, driveshaft) within a compressor housing. Example compression subassemblies include a support plate attached to a non-orbiting scroll that is in turn attached to a main bearing housing with an orbiting scroll positioned therebetween. The support plate separates chambers of the compressor housing that may be at different pressures and creates fluid-tight seals to limit or prevent working fluid from leaking between the chambers. The attachment between the support plate and the non-orbiting scroll allows for the compression subassembly to be assembled and installed in the compressor housing as a single unit. A compression subassembly may be suspended from, or “hang,” within the compressor housing from the support plate, and the support plate includes stop and/or locating features for positioning and centering the support plate on a shell of the compressor housing to provide superior alignment of the compression subassembly therein. In at least some known compressors, the compressor components are installed separately and the compressor housing is used as a primary datum point for the separate connections between the compressor components. Each successive connection between compressor components in these known compressors increases tolerance stack and the opportunity for mis-alignment between compressor components. The example compression subassemblies described provide improvements over known compressors by providing an alignment structure for multiple compressor components that relies only on a single connection point between the support plate and the compressor housing for aligning the components, thus facilitating reducing or eliminating the opportunity for alignment errors.
When introducing elements of the present disclosure or the embodiment(s) thereof, the articles “a”, “an”, “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” “containing,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. The use of terms indicating a particular orientation (e.g., “top,” “bottom,” “side,” etc.) is for convenience of description and does not require any particular orientation of the item described.
As various changes could be made in the above constructions and methods without departing from the scope of the disclosure, it is intended that all matter contained in the above description and shown in the accompanying drawing(s) shall be interpreted as illustrative and not in a limiting sense.