CN116792314A

CN116792314A - Scroll compressor having a rotor with a rotor shaft having a rotor shaft with a

Info

Publication number: CN116792314A
Application number: CN202210259043.6A
Authority: CN
Inventors: 杨春; 吴凌云; 郭伟平
Original assignee: Emerson Climate Technologies Suzhou Co Ltd
Current assignee: Copeland Suzhou Co Ltd
Priority date: 2022-03-16
Filing date: 2022-03-16
Publication date: 2023-09-22

Abstract

The application relates to a scroll compressor, comprising: an intake joint through which a working fluid is sucked from outside the scroll compressor to inside the scroll compressor; a compression mechanism configured to compress a working fluid sucked into the scroll compressor; a main bearing housing including a wall portion defining a recess in which lubricant is collected, the wall portion being provided with a discharge hole adapted to discharge the lubricant in the recess to an outside of the main bearing housing; and a drive shaft supported by the main bearing housing and driving the compression mechanism, the compressor further comprising a lubricant adjustment device provided at the discharge hole and configured to be selectively in an open position allowing lubricant to be discharged and a closed position preventing lubricant from being discharged based on a magnitude of an impact of a flow of working fluid sucked into the inside of the scroll compressor via the intake joint according to a change in a rotational speed of the drive shaft. The application provides a compressor capable of automatically adjusting oil circulation rate to improve performance and reliability.

Description

Scroll compressor having a rotor with a rotor shaft having a rotor shaft with a

Technical Field

The present application relates to a scroll compressor.

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

Scroll compressors typically include a compression mechanism consisting of a fixed scroll member and an orbiting scroll member. In order to ensure proper operation of the compression mechanism, the non-orbiting scroll member and the orbiting scroll member need to be properly lubricated. During operation of the compressor, lubricant supplied to various moving parts in the compressor is thrown out and splashed to form droplets or mist. These lubricant droplets or mist will mix in the working fluid (or refrigerant) drawn in from the intake fitting. These working fluids mixed with lubricant droplets are then drawn into the compression pockets between the non-orbiting and orbiting scroll members to effect lubrication, sealing and cooling of the interiors of these scroll members. This lubrication between the orbiting and non-orbiting scroll members is commonly referred to as oil mist lubrication. In addition, these working fluids mixed with lubricant droplets also achieve lubrication and sealing of the contact surfaces of other components such as cross-slip rings, floating seals, etc.

However, under certain conditions, such oil mist lubrication does not provide sufficient lubricant to the orbiting and non-orbiting scroll members, which increases wear of the orbiting and non-orbiting scroll members and may affect the sealing therebetween, resulting in reduced overall compressor performance.

In the related art, a discharge hole is formed in a wall portion of the main bearing housing to facilitate outflow of lubricant in a recess portion of the main bearing housing, and part of the lubricant that has flowed out is mixed into refrigerant from the intake joint to participate in a compression cycle to enhance lubrication of components in the housing to some extent, and the remaining lubricant is returned to the bottom oil sump.

However, the compressor having the above-described configuration, particularly the inverter compressor, has the following drawbacks: at low rotational speeds, the compressor pumps less oil (e.g., lubricant/oil) so that the recess of the main bearing housing is less lubricant and thus less lubricant flows out of the main bearing housing, the oil circulation rate is small, resulting in insufficient lubrication and part wear, and reduced reliability; at high rotational speeds, the compressor pumps more oil, so that the lubricant in the recess of the main bearing housing and thus the lubricant flowing out of the main bearing housing is more, the intake belt oil quantity is large, the oil circulation rate is large, resulting in reduced performance.

The prior art compressors have oil circulation well below target values at low speeds and well above target values at high speeds. There is therefore a need for lubrication of compressors as follows: at low speeds it is desirable to increase oil circulation to achieve target oil circulation, increase lubrication, and reduce part wear; at high speeds it is desirable to reduce the oil circulation to achieve target oil circulation values, improving system performance.

Disclosure of Invention

The application aims to provide a compressor which can automatically adjust the oil circulation rate through a lubricant adjusting device to improve the system performance and reliability.

According to an aspect of an embodiment of the present application, there is provided a scroll compressor including: an intake joint through which a working fluid is sucked from the outside of the scroll compressor to the inside of the scroll compressor; a compression mechanism configured to compress a working fluid sucked into an interior of the scroll compressor; a main bearing housing including a wall portion defining a recess capable of accumulating lubricant, and provided with a discharge hole adapted to discharge the lubricant in the recess to an outside of the main bearing housing; and a drive shaft supported by the main bearing housing and for driving the compression mechanism, the scroll compressor further including a lubricant adjustment device provided at the discharge hole, and configured to be selectively in an open position allowing lubricant to be discharged and a closed position preventing lubricant from being discharged, according to a change in a rotational speed of the drive shaft, based on a magnitude of an impact of a flow of working fluid sucked into an inside of the scroll compressor via the intake joint.

Advantageously, the lubricant regulating device comprises a movable valve member for selectively opening and closing the outer port of the discharge orifice, and a resilient member arranged in the discharge orifice to exert a resilient force on the valve member against the impact of the working fluid flow.

Advantageously, the discharge hole comprises an inner section of smaller diameter and an outer section of larger diameter so as to form a step, the elastic member being arranged in the outer section and abutting against the step.

Advantageously, the lubricant adjustment device further comprises an end cap adapted to guide the movement of the valve member and/or to define the outermost position of the valve member.

Advantageously, the end cap comprises a bottom wall arranged facing the air intake joint and a circumferential wall arranged to extend from the bottom wall towards the discharge hole, and the end cap comprises a first through hole provided on the circumferential wall and a second through hole provided on the bottom wall.

Advantageously, the first through hole is a plurality of elongated holes uniformly arranged around the circumferential wall, extending in the direction of movement of the valve member, and the second through hole is a single circular hole arranged at the centre of the bottom wall.

Advantageously, an outer periphery of the circumferential wall is fixed to the wall portion of the main bearing housing such that the end cap surrounds the outer port of the discharge bore.

Advantageously, the valve member is a valve plate and the elastic member is a coil spring, one end of which is fixed in the discharge hole and the other end of which is fixed to the valve plate.

Advantageously, the drain hole is positioned below the lubricant level in the recess.

Advantageously, the discharge orifice is positioned such that the central axis of the discharge orifice is higher than the central axis of the air intake fitting.

Advantageously, the compression mechanism is lubricated solely by the lubricant carried by the working fluid.

By adopting the application, the vortex compressor comprising the lubricant adjusting device can automatically adjust the oil content of the air inlet joint along with the change of the rotation speed of the driving shaft, thereby improving the system performance and reliability of the compressor.

Drawings

The features and advantages of one or more embodiments of the present application will become more readily apparent from the following description with reference to the accompanying drawings, in which:

fig. 1 is a partial longitudinal sectional view of a scroll compressor according to an exemplary embodiment of the present application, showing a part of a compression mechanism and a discharge hole on a main bearing housing.

Fig. 2 is a partial longitudinal cross-sectional view of a scroll compressor according to an exemplary embodiment of the present application showing a lubricant adjustment device and the lubricant adjustment device in an open position.

Fig. 3 is an enlarged view of a portion of fig. 2 showing a lubricant adjusting device.

Fig. 4 is a partial longitudinal cross-sectional view of a scroll compressor according to an exemplary embodiment of the present application showing a lubricant adjustment device and the lubricant adjustment device in a closed position.

Fig. 5 is a partial enlarged view of fig. 4 showing the lubricant adjusting device.

Fig. 6 is a perspective view of components of a lubricant adjusting device of a scroll compressor according to an exemplary embodiment of the present application.

Detailed Description

The following description of various embodiments of the application is merely exemplary in nature and is in no way intended to limit the application, its application, or uses. The same reference numerals are used to denote the same parts throughout the various drawings, and thus the construction of the same parts will not be repeated.

The general construction and operation principle of the scroll compressor will be described first with reference to fig. 1. As shown in fig. 1, a scroll compressor 100 (hereinafter, also sometimes referred to as a compressor) generally includes a housing 110, a top cover provided at one end of the housing 110, a bottom cover provided at the other end of the housing 110, and a partition provided between the top cover and the housing 110 to partition an inner space of the compressor into a high pressure side and a low pressure side. The space between the diaphragm and the top cover forms the high pressure side, while the space between the diaphragm, the housing 110, and the bottom cover forms the low pressure side. An intake joint 118 for sucking in fluid is provided on the low pressure side, and an exhaust joint for discharging compressed fluid is provided on the high pressure side. The housing 110 is provided therein with a motor composed of a stator and a rotor. A drive shaft 130 is provided in the rotor to drive a compression mechanism composed of a fixed scroll member and an orbiting scroll member 160. Orbiting scroll member 160 includes an end plate 164, a hub 162 formed on one side of the end plate, and spiral vanes 166 formed on the other side of the end plate. The fixed scroll includes an end plate, a spiral vane formed on one side of the end plate, and a discharge port formed at a substantially central position of the end plate. A series of compression chambers are formed between the spiral vane of the fixed scroll and the spiral vane 166 of the movable scroll 160, the volumes of which gradually decrease from the radially outer side to the radially inner side. Wherein the radially outermost compression chamber is at suction pressure and the radially innermost compression chamber is at discharge pressure. The intermediate compression chamber is between suction and discharge pressures and is therefore also referred to as the intermediate pressure chamber.

One side of orbiting scroll member 160 is supported by thrust plate 141 on main bearing housing 140 and one end of drive shaft 130 is supported by a main bearing disposed in main bearing housing 140. An eccentric crank pin 132 is provided at one end of the drive shaft 130, and an unloading bushing 142 is provided between the eccentric crank pin 132 and a hub 162 of the orbiting scroll 160. By the driving of the motor, the orbiting scroll member 160 will orbit (i.e., the central axis of the orbiting scroll member 160 will orbit the central axis of the orbiting scroll member, but the orbiting scroll member 160 will not itself orbit the central axis of itself) in translation with respect to the non-orbiting scroll member to effect compression of the fluid. The translational rotation is achieved by an oldham ring disposed between the fixed scroll member and the movable scroll member 160. The fluid compressed by the fixed scroll member and the movable scroll member is discharged to the high pressure side through the discharge port.

The lubrication process of each component in the compressor will be described below with reference to the accompanying drawings. In the example of the vertical scroll compressor shown in fig. 1, lubricant is stored in the bottom of the compressor housing. Accordingly, a passage extending substantially in the axial direction thereof, that is, a center hole formed at the lower end of the driving shaft 130 and an eccentric hole (not shown) extending upward from the center hole to the end surface of the eccentric crankpin 132, are formed in the driving shaft 130. The ends of the central bore are immersed in or otherwise supplied with lubricant at the bottom of the compressor housing. In one example, a lubricant supply, such as an oil pump or a fork, may be provided in or near the central bore. During operation of the compressor, one end of the center hole is supplied with lubricant by the lubricant supply device, and the lubricant entering the center hole is pumped or thrown into the eccentric hole by centrifugal force during rotation of the driving shaft 130 and flows up the eccentric hole up to the end face of the eccentric crank pin 132. The lubricant discharged from the end surface of the eccentric crankpin 132 flows down along the gap between the unloading bushing 142 and the eccentric crankpin 132 and the gap between the unloading bushing 142 and the boss 162 into the recess 146 of the main bearing housing 140. A portion of the lubricant that collects in recess 146 flows downward through the main bearing, is agitated by hub 162, moves upward to the underside of end plate 164 of orbiting scroll member 160 and spreads over the thrust surface between orbiting scroll member 160 and thrust plate 141 as orbiting scroll member 160 translates.

During operation of the compressor, lubricant supplied to various moving parts in the compressor is thrown out and splashed to form droplets or mist. These lubricant droplets or mist will mix in the working fluid (or refrigerant) drawn in from the intake fitting. These working fluids mixed with lubricant droplets are then drawn into the compression pockets between the non-orbiting and orbiting scroll members to effect lubrication, sealing and cooling of the interiors of these scroll members to effect lubrication of the oil mist between the orbiting and non-orbiting scroll members.

Referring again to FIG. 1, the main bearing housing includes a wall portion 148, the wall portion 148 defining a recess 146 capable of collecting lubricant that would drain from the eccentric bore of the drive shaft 130 into the recess 146 of the main bearing housing 140. Also, the wall portion 148 is provided with a discharge hole 143 adapted to discharge the lubricant in the recess to the outside of the main bearing housing, and a part of the discharged lubricant is mixed into the refrigerant from the intake joint to participate in the compression cycle to provide lubrication to the components in the housing, and the remaining lubricant is returned to the bottom oil pool. This configuration compensates to some extent for the disadvantage of performance degradation caused by insufficient lubrication of the oil mist lubrication (particularly under certain conditions).

However, the compressor having this configuration, in particular a variable frequency compressor, has the following drawbacks: at low rotational speeds, less oil is pumped (lubricant) so that less lubricant flows out from the bearing seat, the oil circulation is much lower than the target value, and the lubrication is insufficient; and at high rotation speed, more oil is pumped, so that more lubricant flows out from the bearing seat, the oil circulation is greatly higher than the target value, the oil quantity of the suction belt is large, and the performance is reduced.

There is therefore a need for: at low speeds, it is desirable to increase the oil circulation to achieve target oil circulation values, reducing part wear; at high speeds it is desirable to reduce the oil circulation to achieve target oil circulation values and improve product performance.

Next, a scroll compressor having a lubricant adjusting apparatus according to an embodiment of the present application will be described with reference to fig. 1 to 6. Fig. 1 is a partial longitudinal sectional view of a scroll compressor according to an exemplary embodiment of the present application, showing a part of a compression mechanism and a discharge hole on a main bearing housing. Fig. 2 is a partial longitudinal cross-sectional view of a scroll compressor according to an exemplary embodiment of the present application showing a lubricant adjustment device and the lubricant adjustment device in an open position. Fig. 3 is an enlarged view of a portion of fig. 2 showing a lubricant adjusting device. Fig. 4 is a partial longitudinal cross-sectional view of a scroll compressor according to an exemplary embodiment of the present application showing a lubricant adjustment device and the lubricant adjustment device in a closed position. Fig. 5 is a partial enlarged view of fig. 4 showing the lubricant adjusting device. Fig. 6 is a perspective view of components of a lubricant adjusting device of a scroll compressor according to an exemplary embodiment of the present application.

The configuration and arrangement of the lubricant adjusting device of the scroll compressor of the present application will now be described with reference to fig. 2, the lubricant adjusting device 120 is provided at the discharge hole 143, and the lubricant adjusting device may be configured to be selectively in an open position allowing the lubricant to be discharged and a closed position preventing the lubricant from being discharged, based on the magnitude of the impact of the working fluid flow sucked into the inside of the scroll compressor via the intake joint, according to the change in the rotation speed of the driving shaft.

Referring again to fig. 3, 5 and 6, the lubricant adjusting device 120 may include a movable valve member 121 for selectively opening and closing an outer port of the discharge hole 143, and an elastic member 122 disposed in the discharge hole to apply an elastic force to the valve member against an impact of the sucked working fluid flow. The discharge hole 143 may include an inner section having a smaller diameter and an outer section having a larger diameter so as to be formed with a stepped portion, and the elastic member 122 is disposed in the outer section and abuts against the stepped portion. And wherein the lubricant regulating device 120 may further comprise an end cap 123, the end cap 123 comprising a bottom wall 126 arranged to face the air inlet joint 118 and a circumferential wall 127 arranged to extend from the bottom wall towards the discharge hole, wherein the circumferential wall 127 guides the valve member 121 in motion, and the bottom wall 126 may define an outermost position of the valve member 121. Also, the end cap 123 may further include a first through hole 124 provided on the circumferential wall 127 and a second through hole 125 provided on the bottom wall 126. In one aspect of an embodiment, the outer periphery of circumferential wall 127 may be secured to wall portion 148 of the main bearing housing such that the end cap surrounds the outer port of discharge hole 143.

According to the scroll compressor including the above-described lubricant adjusting device of the present application, the lubricant adjusting device is in the open position at the low rotation speed of the driving shaft, in particular, at the low speed operation, since the air flow from the air intake joint is low, the valve plate is in the open state against the air force of the low speed air flow by the spring force to allow the lubricant in the recess of the main bearing housing to be discharged from the discharge hole, and the discharged lubricant is carried by the fluid from the air intake joint into the compression structure to lubricate, that is, to improve the oil circulation at the low rotation speed, thereby reducing the wear of the parts. When the rotation speed of the driving shaft is high, the lubricant adjusting device sucks more fluid through the air inlet joint, so that the speed and impact of the fluid flow are increased, the valve plate is in a closed position against the elastic force of the elastic component under the action of the high-speed fluid from the air inlet joint, the lubricant in the concave part of the main bearing seat is prevented from being discharged from the discharge hole, and the lubricant in the concave part is isolated from the fluid from the air inlet joint, so that the fluid from the air inlet joint does not carry the lubricant, namely, the oil circulation is reduced at the high rotation speed, and the product performance is improved. More precisely, according to the application, at each section of full speed, there is a suitable oil circulation rate, at low speeds the oil circulation is not much lower than the target value of the oil circulation, and at high speeds the oil circulation is not much higher than the target value of the oil circulation. That is, the object of the present application is: the target value of the oil circulation can be reached at both high and low speeds. Therefore, the scroll compressor according to the present application can automatically adjust the oil content of the intake joint as the rotation speed of the drive shaft changes, more precisely, automatically adjust the lubricating oil carried by the fluid to be introduced into the compression mechanism from the intake joint, improving the performance and reliability of the scroll compressor, which is particularly advantageous for variable frequency scroll compressors.

The operating state of the lubricant adjusting device will be described below with reference to fig. 1 to 6, at low rotational speeds of the drive shaft 130, the valve member 121 is urged against the bottom wall 126 of the end cap 123 away from the discharge hole 143 to be in an open position (see fig. 3) by the elastic member 122 to allow lubricant from the recess 146 to be discharged from the discharge hole 143, and the lubricant can flow out of the end cap through the first through hole 124, and the lubricant is thereby carried by fluid from the intake joint 118 into the compression structure for lubrication to increase the oil circulation rate to reach the target value of oil circulation at low rotational speeds, thereby reducing wear of parts. At a higher rotational speed of the drive shaft 130, the fluid sucked through the intake joint 118 is more, and thus the speed and impact of the fluid flow become greater, the valve member 121 abuts against the stepped portion of the discharge hole against the elastic force of the elastic member 121 and closes the discharge hole to be in the closed position (see fig. 5) under the action of the fluid flowing into the end cap from the intake joint 118 through the second through hole 125, preventing the lubricant in the recess of the main bearing housing from being discharged from the discharge hole, and thus the fluid from the intake joint does not carry the lubricant, to reduce the oil circulation rate to reach the target value of the oil circulation at a high rotational speed, thereby improving the system performance.

In an advantageous aspect of the embodiment, the first through holes 124 may be a plurality of elongated holes, which are uniformly arranged around the circumferential wall, extending in the direction of movement of the valve member (axial direction of the end cap), and which may be holes of a larger size in the axial direction of the end cap and of a smaller size in the circumferential direction of the end cap. Also, the second through hole 125 may be a single circular hole provided at the center of the bottom wall 126. The plurality of elongated/transverse holes facilitate efficient outflow of lubricant to improve lubrication; the central circular aperture allows for a more uniform and focused impact of fluid flowing into the end cap on the valve member, making the regulator more effective. In addition, a portion of the fluid from the intake fitting may pass through the lower elongated hole/cross hole to meet the lubricant flowing out of the discharge hole 143 to carry the lubricant out of the lower elongated hole/cross hole and into the compression mechanism.

In another aspect of the embodiment, the valve member 121 may be a valve plate, and the elastic member 122 may be a coil spring, one end of which is fixed in the discharge hole and the other end of which is fixed to the valve plate. The valve member may also be a ball valve or reed valve, as desired. For example, in particular, the reed valve may include a valve member for opening and closing the discharge hole and a valve arm portion that applies an elastic force to the valve member. The reed valve may be disposed outside the wall of main bearing housing 140 and the valve arm may be secured to the wall of main bearing housing 140 with only screws or rivets or the like. Similar advantageous effects as those of the above embodiment can be achieved.

The stiffness of the coil spring is adjustable. It is advantageous to choose a coil spring with a suitable stiffness for a specific compressor, for the operating conditions (high speed or low speed or high speed) in which the compressor is to be (mainly) operated, and/or for the oil circulation rate to be predetermined to be achieved.

In other aspects of embodiments of the application, the drain hole may be positioned below the lubricant level in the recess to facilitate draining of lubricant. And, the drain hole is positioned such that a central axis of the drain hole is higher than a central axis of the intake fitting such that fluid flow from the intake fitting is allowed when in the open position to more fully meet the lubricant to carry the lubricant. Furthermore, the compression mechanism of the present application may be lubricated only by the lubricant carried by the working fluid.

Although various embodiments of the present application have been described in detail herein, it is to be understood that the application is not limited to those precise embodiments described and shown herein, and that other modifications and variations may be effected by one skilled in the art without departing from the spirit or scope of the application. All such modifications and variations are intended to be within the scope of the present application. Moreover, all the components described herein may be replaced by other technically equivalent elements.

Claims

1. A scroll compressor comprising:

an intake joint (118) through which a working fluid is drawn from outside the scroll compressor to inside the scroll compressor;

a compression mechanism configured to compress a working fluid sucked into an interior of the scroll compressor;

-a main bearing housing (140), the main bearing housing comprising a wall portion (148), the wall portion (148) defining a recess (146) capable of collecting lubricant, and the wall portion being provided with a discharge hole (143) adapted to discharge lubricant within the recess to the outside of the main bearing housing; and

a drive shaft (130) supported by the main bearing housing and for driving the compression mechanism,

characterized in that the scroll compressor further comprises a lubricant adjustment device (120) provided at the discharge hole, and the lubricant adjustment device is configured to be selectively in an open position allowing lubricant discharge and a closed position preventing lubricant discharge based on the magnitude of an impact of a flow of working fluid sucked into the interior of the scroll compressor via the intake joint according to a change in the rotational speed of the drive shaft.

2. The scroll compressor according to claim 1, wherein the lubricant adjustment device (120) comprises a movable valve member (121) for selectively opening and closing an outer port of the discharge orifice and a resilient member (122) arranged in the discharge orifice to exert a resilient force on the valve member against an impact of a flow of working fluid.

3. The scroll compressor of claim 2, wherein the discharge hole includes an inner section having a smaller diameter and an outer section having a larger diameter so as to be formed with a stepped portion, the elastic member being disposed in the outer section and abutting against the stepped portion.

4. The scroll compressor according to claim 2, wherein the lubricant adjustment device (120) further comprises an end cap (123) adapted to guide the movement of the valve member (121) and/or adapted to define an outermost position of the valve member (121).

5. The scroll compressor according to claim 4, wherein said end cap (123) includes a bottom wall (126) arranged to face said intake fitting and a circumferential wall (127) arranged to extend from said bottom wall toward said discharge aperture, and said end cap includes a first through hole (124) provided in said circumferential wall and a second through hole (125) provided in said bottom wall.

6. The scroll compressor according to claim 5, wherein said first through hole (124) is a plurality of elongated holes evenly arranged around said circumferential wall extending in the direction of movement of said valve member, and said second through hole (125) is a single circular hole arranged at the center of said bottom wall.

7. The scroll compressor according to claim 5 wherein an outer periphery of said circumferential wall (127) is secured to said wall portion (148) of said main bearing housing such that said end cap surrounds said outer port of said discharge bore (143).

8. The scroll compressor according to claim 2, wherein the valve member (121) is a valve plate, and the elastic member (122) is a coil spring, one end of which is fixed in the discharge hole and the other end of which is fixed to the valve plate.

9. The scroll compressor of any one of claims 1 to 8, wherein the discharge aperture is positioned below a lubricant level in the recess.

10. The scroll compressor of any one of claims 1 to 8, wherein the discharge aperture is positioned such that a central axis of the discharge aperture is higher than a central axis of the intake fitting.

11. The scroll compressor of any one of claims 1 to 8, wherein the compression mechanism is lubricated solely by lubricant carried by the working fluid.