Patent Application
20240318652
The field relates generally to systems and methods for driveshaft assemblies and compressors, and more particularly, to shaft-through driveshaft assemblies including an unloader assembly for use in compressors.
Scroll compressors compress refrigerant using a scroll assembly including 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 the driveshaft assemblies and a drive bearing for transmitting rotational motion of the driveshaft to the orbiting motion of the scroll member. The drive bearing is provided between a drive coupling of an 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, the driveshaft is typically exposed to a variety of loads resulting from driving the orbiting scroll, rotations of counterweights, rotor torque, and bearing reaction forces. These loads may cause deflection of the driveshaft. The magnitude of driveshaft deflection may be dependent on the rotational speed and the operating condition of the compressor. Driveshaft deflection, under these applied loads, may lead to bearing wear and/or compressor failure.
Efficient and reliable operation of the compressor is desirable 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. Furthermore, reducing wear on components, such as bearing assemblies, of the scroll compressor may increase the longevity of the compressor and the climate-control system.
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.
In one aspect, a compressor includes a shell and a scroll assembly disposed within the shell. The scroll assembly includes a non-orbiting scroll connected to the shell and including a first opening, and an orbiting scroll including a spiral wrap and a second opening including a drive bearing disposed therein, wherein the drive bearing is axial aligned with the spiral wrap. The compressor includes a driveshaft including a driveshaft body and an eccentric body. The eccentric body is disposed within the second opening and drivingly engaged with the orbiting scroll. The compressor includes a primary bearing disposed within the first opening of the non-orbiting scroll and an unloader rotationally connected to the driveshaft body and rotationally supported with the primary bearing. In another aspect, a compressor includes a shell and a scroll assembly disposed within the shell. The scroll assembly includes a non-orbiting scroll connected to the shell and including a first opening, and an orbiting scroll including a spiral wrap and a second opening including a drive bearing disposed therein, wherein the drive bearing is axial aligned with the spiral wrap. The compressor includes a driveshaft including a driveshaft body and an eccentric body. The eccentric body is disposed within the second opening and drivingly engaged with the orbiting scroll. The compressor includes a primary bearing connected to the shell and axially displaced from the non-orbiting scroll and an unloader rotationally connected to the driveshaft body and rotationally supported with the primary bearing.
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 characters indicate corresponding parts throughout the drawings.
Referring to
The compressor 100 may include various drive assemblies A-L, shown in
The driveshaft 132 includes a driveshaft body 134 and an eccentric body 136 that may be offset from the driveshaft body 134. The driveshaft body 134 and the eccentric body 136 are both generally cylindrical in shape. The driveshaft body 134 includes a longitudinal axis extending in an axial direction between a first end portion and a second end portion that is axially spaced from the first end portion. In some embodiments, the eccentric body 136 extends from the first end of the driveshaft body 134. In other embodiments, the eccentric body 136 is positioned axially between the first end and the second end of the driveshaft body 134.
The compressor 100 may include at least one of a primary bearing 150 and/or a secondary bearing 152 that rotationally supports the driveshaft 132. The primary bearing 150 and/or the secondary bearing 152 may be rolling element bearings having an inner ring, an outer ring spaced radially outward from the inner ring, and a plurality of balls or rollers disposed between the inner ring and the outer ring. The inner ring includes an inner surface, e.g., a bearing surface, defining a bearing opening. Alternatively, in some embodiments, the primary bearing 150 and/or secondary bearing 152 are journal bearings, having the bearing surface defining the bearing opening. The primary bearing 150 and/or the secondary bearing 152 may rotationally support the driveshaft 132. If the primary bearing 150 and/or the secondary bearing 152 are rolling element bearings, the driveshaft 132 rotates with the inner ring. Alternatively, if the primary bearing 150 and/or the secondary bearing 152 are journal bearings, the driveshaft 132 rotates within the bearing opening and relative to the stationary bearing inner surface. The primary bearing 150 and/or the secondary bearing 152 may be any suitable bearing type.
The compressor 100 may include a first scroll side 154 and a second scroll side 156, axially displaced from the first scroll side 154, defined on either side of the scroll assembly 120. The first scroll side 154 is generally near the end cap 106 and the second scroll side 156 is generally near the motor assembly 126. The compressor 100 may also include a first motor side 158 and an opposing second motor side 159 axially displaced from the first motor side 158.
The orbiting scroll 122 includes a plate 160 including a spiral wrap 162 extending therefrom. The plate 160 defines an orbiting scroll opening 164 that is sized and shaped to receive a drive bearing 166 therein. The orbiting scroll opening 164 may be disposed generally in a center of plate 160 and spiral wrap 162. The drive bearing 166 may be in axial alignment with the spiral wrap 162. The eccentric body 136, of the driveshaft 132, is drivingly engaged to the drive bearing 166. The eccentric body 136 extends into, and/or through, the orbiting scroll opening 164 defined in the orbiting scroll 122. The rotational motion of the driveshaft 132 is transformed into the orbiting motion of the orbiting scroll 122 through the eccentric body 136 and the drive bearing 166. The non-orbiting scroll 124 includes a plate 168 and a spiral wrap 170 extending axially from the plate 168. The non-orbiting scroll 124 defines a non-orbiting scroll opening 172 that is generally aligned with the primary and/or secondary bearings 150 and 152. The non-orbiting scroll 124 may also include a hub, extending on an opposite side of the plate 168 from the spiral wrap 170. The hub may, at least partially, define the non-orbiting scroll opening 172. The primary bearing 150 or the secondary bearing 152 may be disposed within the non-orbiting scroll opening 172 of the non-orbiting scroll 124 when a bearing is used in the non-orbiting scroll.
The spiral wrap 170 may engage, mesh, with the spiral wrap 162 of the orbiting scroll 122 thereby creating a series of moving fluid pockets. The fluid pockets defined by the spiral wraps 162, 170 may decrease in volume as they move from a radially outer position (e.g., suction pocket at a suction pressure) to a radially inner position (e.g., discharge pocket at a discharge pressure that is higher than the suction pressure) throughout a compression cycle. The plates 160, 168 may include a discharge passage in communication with at least one of the fluid pockets at the radially inner position and allows compressed working fluid, such as refrigerant or a mixture of refrigerant and lubricant (at or near the discharge pressure) to flow therethrough.
The compressor 100 may further include an upper housing 186. The upper housing 186 may be connected to at least one of the compressor housing 102, e.g., the shell 104, and/or the non-orbiting scroll 124. The compressor 100 may also include a lower bearing bracket 188 connected to the compressor housing 102, e.g., the shell 104. The upper housing 186, the lower bearing bracket 188, and/or the non-orbiting scroll 124 may support at least one of the primary and/or the secondary bearings 150, 152, as described herein. For example, the upper housing 186 may define an upper opening 190 and the lower bearing bracket 188 may defined a lower opening 192. The primary bearing 150 or the secondary bearing 152, may be disposed, at least partially within either of the upper opening 190 and/or the lower opening 192. The upper opening 190 and/or the lower opening 192 may define the bearing surface. For example, at least one of the upper opening 190 and the lower opening 192 may be a journal bearing. The upper housing 186 may be arranged on either the first scroll side 154, see drive assemblies D, E, G, H, I, K, and L (
The compressor 100 may be referred to as a “shaft-through” scroll compressor. In the “shaft-through” scroll compressor 100 described herein, the drive bearing 166 is located in a horizontal plane that is aligned with the spiral wrap 162 of the orbiting scroll 122. For example, the drive bearing 166 is at least partially axially aligned with the spiral wrap 162. See drive assemblies A-L (
The compressor 100 also includes an unloader 200 that is rotationally supported by at least one of the primary bearing 150 or the secondary bearing 152. Alternatively, in some embodiments, the unloader 200 may be rotationally supported by the drive bearing 166. The unloader 200 is disposed within the bearing opening and if the unloader 200 is rotationally supported by a roller bearing, the unloader 200 rotates along with the inner ring, alternatively, if the unloader 200 is rotationally supported by a journal bearing, the unloader 200 rotates relative to the bearing surface. The driveshaft 132, e.g., the driveshaft body 134, may include a recess 194, and at least a portion of the unloader 200 may be at least partially disposed within the recess 194. The unloader 200 provides compliance, between the driveshaft 132 and at least one of the primary bearing 150, the secondary bearing 152, and/or the drive bearing 166. The unloader 200 may provide compliance in a direction perpendicular, e.g., radially and/or tangentially, relative to the longitudinal axis of the driveshaft 132. In some embodiments, the unloader 200 may generally be in the shape of a cylindrical segment, having an outer surface 206, generally a cylindrical surface, and a flank surface 204 that is generally planar. See
Alternatively, in some embodiments, the unloader 200 may be generally annular in shape defining an unloader opening. See
The compressor 100, including drive assemblies A-L, shown in
The unloader 200 may be rotationally supported by the secondary bearing 152. See drive assemblies F and H (
The compressor 100 includes a coupling 202, such as an Oldham coupling, engaged with the orbiting scroll 122 and at least one of the non-orbiting scroll 124, the upper housing 186, and/or the compressor housing 102 to prevent relative rotation therebetween. In drive assemblies A-L (
The compressor 100 may include at least one of a first counterweight 210 and/or a second counterweight 212. The first and second counterweights 210, 212 are connected to the driveshaft 132, e.g., the driveshaft body 134 and/or the rotor 130, such that rotations of the driveshaft 132 rotates the first and second counterweights 210, 212. The axial position of the first and second counterweights 210, 212, e.g., relative to the scroll assembly 120, may be different for the various drive assemblies A-L (
The compressor 100 may include both of the first and second counterweights 210, 212. The first counterweight 210 and the second counterweight 212 may be positioned, axially, on opposing scroll sides 154, 156 of the scroll assembly 120. See drive assemblies B-D (
In some embodiments, the first and second counterweights 210, 212 may both rotationally connected to a portion of driveshaft 132 that is disposed on the second scroll side 156 of the scroll assembly 120. See drive assembly A, E, I, J, K, and L (
The compressor 100 further includes one or more a first seal 216, e.g., an intermediate cavity pressure (ICP) seal, which may be disposed between the upper housing 186 and the orbiting scroll 122. See drive assemblies A-L (
The first and second seals 216, 218 may be ring shaped, and the first and second seals 216, 218 may be arranged concentrically. In some embodiments, the first seal 216 may be disposed between the upper housing 186 and the non-orbiting scroll 124 and the second seal 218 is disposed between the orbiting scroll 122 and the non-orbiting scroll 124. The various combination of seal configuration enables optimized axial balancing improving compressor efficiency. The compressor 100 may also include a lid 222, that covers at least one of the orbiting scroll opening 164 or the non-orbiting scroll opening 172. See drive assemblies I and J (
The upper housing 186 may be disposed on the first scroll side 154 of the scroll assembly 120 and the lower bearing bracket 188 is disposed on the second scroll side 156 of the scroll assembly 120. See drive assemblies D, E, I, K, and L (
The secondary bearing 152 may be supported by the lower bearing bracket 188. See drive assemblies A, B, D, E, I, J, K, and L (
Embodiments of the systems and methods of the present disclosure achieve superior results as compared to prior systems and methods. In particular, the compressor including both an unloader and a shaft-through scroll design in which the drive bearing is axially aligned with the spiral wrap of the orbiting scroll, have known benefits over other compressors. For example, the shaft-through scroll design may have a reduced bending moment on the driveshaft as compared to non-shaft-through scroll designs. In addition, the unloader provides driveshaft compliance to unload forces on the driveshaft caused by driveshaft deflections and control scroll flank contact forces independent of compressor speed. Accordingly, the shaft-through scroll design combined with the unloader, has improved scroll flank wear behavior and reduced scroll flank friction while maintaining tight flank-to-flank sealing compared to other known compressors. In addition, the shaft-through scroll compressors minimize a tipping moment of the orbiting scroll resulting in improved compressor balance and efficiency as friction is reduced between the thrust surfaces of the scrolls. Further, embodiments of the shaft-through scroll compressors have reduced noise levels.
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.
