CN217950683U - Compression mechanism and scroll compressor - Google Patents

Abstract

The utility model relates to a compression mechanism and scroll compressor, compression mechanism includes: the compression mechanism comprises an orbiting scroll with an orbiting scroll end plate and an orbiting scroll blade formed at one side of the orbiting scroll end plate, a fixed scroll with a fixed scroll end plate and a fixed scroll blade formed at a first side of the fixed scroll end plate, and an orbiting scroll blade and a fixed scroll blade engaged with each other to form a suction chamber, a central compression chamber and a plurality of intermediate compression chambers between the orbiting scroll and the fixed scroll. Wherein the compression mechanism is provided with a drainage channel comprising a first drainage channel selectively providing fluid communication between the suction chamber and an exterior of the compression mechanism and/or a second drainage channel selectively providing fluid communication between an intermediate compression chamber of the plurality of intermediate compression chambers, which is adjacent to the suction chamber, and the exterior of the compression mechanism. According to the utility model discloses a scroll compressor can realize effective flowing back, excellent performance, operation are reliable.

Description

Compression mechanism and scroll compressor

Technical Field

The present invention relates to a scroll compressor, and more particularly, to a scroll compressor having a drainage design.

Background

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

Scroll compressors are known as compression machines of the capacity type. The scroll compressor includes a compression mechanism composed of a fixed scroll and an orbiting scroll. Generally, the fixed scroll and the orbiting scroll each include scroll blades, which are engaged with each other to form a series of compression chambers between the fixed scroll and the orbiting scroll to compress a working fluid, and compressed high-pressure gas is discharged through a discharge port at the center of the fixed scroll.

Conventional scroll compressors typically employ an axially compliant design, i.e., the non-orbiting and orbiting scrolls may be axially separated from one another by a distance for unloading high pressure fluid (such as gaseous refrigerant) or discharging excess liquid (such as liquid refrigerant during initial start-up of the compressor), for example, when the pressure within the compression chambers is too high.

However, for a large-displacement scroll compressor, the axial separation distance of the compression mechanism is limited, even the design of axial flexibility is completely absent, so that liquid in the compression cavity cannot be discharged in time, and the situation that the scroll blade is subjected to great impact force under the working condition of liquid carrying is easy to happen, so that the scroll blade is cracked. In addition, still can produce very big moment of torsion in the twinkling of an eye at scroll compressor's start-up, produce certain impact to the motor, influence the life of the motor of working under the operating mode of frequently opening and stopping very easily.

Accordingly, there is a need for an improved liquid discharge design and method of liquid discharge control for scroll compressors, particularly high capacity scroll compressors.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a compression mechanism and scroll compressor with new flowing back mechanism, this compression mechanism can be with the chamber of breathing in or be close to the flowing back passageway of the middle compression chamber in chamber of breathing in and compression mechanism's outside intercommunication through setting up in deciding the vortex, can in time discharge the too much liquid in the compression chamber, has effectively avoided scroll compressor's start liquid to hit the damage.

Another object of the utility model is to provide a scroll compressor, this scroll compressor has reduced the start moment of torsion of compressor through the switching period of rationally controlling flowing back passageway, avoids the start moment of torsion of motor too big, has reduced motor impact load to motor life has been improved.

According to an aspect of the utility model, a compression mechanism is provided, include: an orbiting scroll having an orbiting scroll end plate and an orbiting scroll blade formed at one side of the orbiting scroll end plate; a fixed scroll having a fixed scroll end plate and a fixed scroll blade formed at a first side of the fixed scroll end plate, the movable scroll blade and the fixed scroll blade being engaged with each other to form a suction chamber, a central compression chamber and a plurality of intermediate compression chambers between the movable scroll and the fixed scroll; wherein the compression mechanism is provided with a drainage channel comprising a first drainage channel configured to selectively provide fluid communication between the suction chamber and an exterior of the compression mechanism and/or a second drainage channel configured to selectively provide fluid communication between an intermediate compression chamber of the plurality of intermediate compression chambers that is adjacent to the suction chamber and the exterior of the compression mechanism.

Optionally, a piston is disposed within the drainage channel that is movable between an open position providing fluid communication and a closed position not providing fluid communication.

Optionally, a drainage channel is provided in the non-orbiting scroll end plate and is configured as a piston bore extending from a second side of the non-orbiting scroll end plate opposite the first side to the first side, the piston bore having a liquid inlet communicating with the suction chamber or with an intermediate compression chamber adjacent the suction chamber, and the piston bore having a liquid outlet communicating with an exterior of the compression mechanism at a side of the piston bore.

Optionally, a cover is provided on the second side of the non-orbiting scroll end plate, the cover covering and sealing the piston port, thereby forming a pressure control chamber in an area between the cover and the piston within the piston port.

Optionally, the compression mechanism further includes a solenoid valve disposed outside the non-orbiting scroll, and a first pressure control passage extending substantially in a direction transverse to an axial direction of the compression mechanism is formed in the non-orbiting scroll end plate, the first pressure control passage being connected to the solenoid valve and communicating with the pressure control chamber.

Optionally, a second pressure control passage extending generally in a direction transverse to the axial direction of the compression mechanism is also formed in the non-orbiting scroll end plate, the second pressure control passage being connected to the solenoid valve and communicating with an intermediate compression chamber, of the central compression chamber or chambers, which is close to the central compression chamber.

Optionally, the solenoid valve has a first state and a second state, the solenoid valve being in the first state to communicate the first pressure control passage with an exterior of the compression mechanism during a flooded condition of the compression mechanism and the solenoid valve being in the second state to communicate the first pressure control passage with the second pressure control passage during a non-flooded condition of the compression mechanism.

Optionally, the drainage channels comprise two sets of drainage channels arranged substantially symmetrically on either side of a central axis of the compression mechanism.

Optionally, at least one of the two sets of liquid discharge passages includes a plurality of piston ports, and a communication groove is formed at the second side of the non-orbiting scroll end plate, the communication groove communicating the pressure control chamber in each of the plurality of piston ports.

Optionally, a side groove extending outward from the piston bore is formed at the second side of the non-orbiting scroll end plate, the side groove communicating with the first pressure control passage.

Optionally, a seal is provided between the piston and the piston bore, which always isolates the liquid outlet from the pressure control chamber in the event of the piston being in any position.

Optionally, the base of the piston bore is formed with a sealing seat engageable with the lower end of the piston and forming a seal against the liquid inlet.

Optionally, the piston bore is configured to: when viewed in the axial direction of the compression mechanism, a portion of the piston port overlaps the non-orbiting scroll blade.

The utility model also provides a scroll compressor of the compressing mechanism who includes above-mentioned description.

Optionally, the scroll compressor further comprises a controller adapted to control a solenoid valve of the compression mechanism disposed externally of the non-orbiting scroll to control a piston disposed within the liquid drainage channel such that the liquid drainage channel provides fluid communication during start-up of the scroll compressor or upon detection of the scroll compressor being in a flooded condition.

According to the utility model discloses a compression mechanism and scroll compressor adopt new flowing back control mechanism, can discharge the too much liquid in the compression chamber in time, prevent effectively that the start liquid of compressor from hitting the damage, simple structure, reliability are high, easily production and manufacturing. According to the utility model discloses scroll compressor's flowing back control adopts the control logic of optimization, can reduce the start moment of torsion of compressor, prolongs the life of motor effectively.

Drawings

Features and advantages of one or more embodiments of the present invention will become more readily understood by the following description with reference to the accompanying drawings, in which:

fig. 1 is an exploded perspective view of a compression mechanism of a scroll compressor according to an embodiment of the present invention, in which an orbiting scroll is not shown in the drawing;

fig. 2 is a top view of a compression mechanism of a scroll compressor according to an embodiment of the present invention, showing a liquid discharge passage and a piston;

fig. 3a and 3b are longitudinal sectional views of a compression mechanism of a scroll compressor according to an embodiment of the present invention in a liquid discharge state and in a non-liquid discharge state, respectively, in which a movable scroll is not shown in the drawings;

fig. 4 is a cross-sectional view of a non-orbiting scroll of a compression mechanism of a scroll compressor according to an embodiment of the present invention, showing a solenoid valve and a pressure control passage; and

fig. 5a and 5b are longitudinal sectional views of additional sections of a compression mechanism of a scroll compressor according to an embodiment of the present invention, in which a pressure control passage is shown.

Detailed Description

Exemplary embodiments will now be described more fully with reference to the accompanying drawings.

The exemplary embodiments are provided so that this disclosure will be thorough and will more fully convey the scope to those skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, in order to provide a thorough understanding of embodiments of the present invention. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the invention. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

The overall structure of a scroll compressor, and particularly a compression mechanism of a scroll compressor according to an embodiment of the present invention, is described below with reference to fig. 1. Generally, a scroll compressor includes a compression mechanism, a motor (electric motor), a rotary shaft, a main bearing housing, and a housing defining an inner space accommodating the above components. The interior space of the housing defines a suction pressure region and a discharge pressure region.

The compression mechanism includes a fixed scroll 100 and an orbiting scroll (not shown in the drawings). The movable scroll includes a movable scroll end plate and a movable scroll blade formed at one side of the movable scroll end plate. Non-orbiting scroll 100 includes a non-orbiting scroll end plate 10 and a non-orbiting scroll blade 20 (fig. 3a, 3 b) extending from a first side of the non-orbiting scroll end plate 10. The non-orbiting and orbiting scroll blades 20 and 20 are engageable with each other such that a series of compression chambers including a central compression chamber CO located at the center of the non-orbiting scroll 100 and communicating with a discharge port 17 (fig. 2, 3a, 3 b) at the center of the non-orbiting scroll end plate 10, a suction chamber CI located radially outside of the non-orbiting scroll 100 and communicating with a suction port of the non-orbiting scroll 100, and a plurality of intermediate compression chambers C located between the central compression chamber CO and the suction chamber CI are formed between the non-orbiting scroll blades 20 and the orbiting scroll blades when the scroll compressor is operated (each compression chamber is only schematically labeled since the orbiting scroll is omitted in fig. 3a, 3 b). The motor is configured to rotate a rotary shaft that drives the orbiting scroll to orbit relative to the non-orbiting scroll 100 (i.e., the central axis of the orbiting scroll orbits the central axis of the non-orbiting scroll, but the orbiting scroll does not orbit around its central axis), and refrigerant fluid enters the compression mechanism from a suction pressure region, is compressed via a series of compression chambers, is discharged from a discharge port 17 in the center of the non-orbiting scroll end plate 10, and is discharged to a discharge pressure region.

In order to achieve the liquid discharge of the compression mechanism, a liquid discharge passage is formed in the non-orbiting scroll end plate 10. As shown in fig. 3a and 3b, the liquid discharge passage is configured as a piston port 12 extending from a second side of the non-orbiting scroll end plate 10 opposite to the first side thereof to the first side, the bottom end of the piston port 12 having a liquid inlet 15 communicating with the suction chamber CI, the piston port 12 having a liquid outlet 14 at a side thereof communicating with a suction pressure region outside the compression mechanism. In order to increase the flow area so that the liquid can be discharged more smoothly, the liquid outlet 14 may preferably be provided in the form of an elongated groove extending away from the piston port 12 from the side of the piston port 12 in a direction tangential to the side wall of the piston port 12 (see fig. 1), and the second side surface of the non-orbiting scroll end plate 10 is recessed downward to form a liquid discharge reservoir 16, the liquid discharge reservoir 16 being configured to communicate with the liquid outlet 14 so as to facilitate the liquid to flow out from the liquid outlet 14. Furthermore, the piston port 12 may preferably be configured such that: when viewed in the axial direction of the compression mechanism, a part of the piston port 12 overlaps the non-orbiting scroll blade 20. By this configuration, it is possible to further increase the area of the liquid inlet 15 on the one hand, enabling liquid to enter the liquid discharge channel more quickly, and on the other hand, to facilitate the positional design of the piston bore 12 while ensuring the functionality of the liquid inlet 15.

The compression mechanism also includes a liquid discharge control mechanism located generally on the second side of the non-orbiting scroll end plate 10. The liquid discharge control mechanism mainly includes a controller (not shown in the figure), the solenoid valve 30, the piston 51, the cover member, and the fixing member 54. The piston 51 is disposed within the piston bore 12 and is movable along the piston bore 12 between an open position and a closed position. Preferably, the lower end surface of the piston 51 is configured as a conical surface, a spherical surface or a flat surface, the base of the piston bore 12 is formed with a sealing seat, and the lower end surface of the piston 51 is capable of engaging with the sealing seat of the piston bore 12 and forming a seal against the liquid inlet 15.

The cover includes a packing 53 and a cover plate 52, and the packing 53 and the cover plate 52 are sequentially mounted and fixed to the second side surface of the non-orbiting scroll end plate 10 and cover over the piston port 12 to form a seal by inserting a fixing member 54, such as a screw, into the mounting hole of the non-orbiting scroll end plate 10 through the mounting hole of the cover plate 52 and the packing 53 in sequence, thereby forming a pressure control chamber CP in an area between the cover and the piston 51 within the piston port 12. The pressure in the pressure control chamber CP is regulated by the solenoid valve 30 to control the pressure difference between above and below the piston, and the piston 51 can be moved to its open or closed position as required.

A solenoid valve 30 is provided in the receiving recess 18 formed in the second side of the non-orbiting scroll end plate 10, the solenoid valve 30 regulating the pressure within the pressure control chamber CP through a pressure control passage formed in the non-orbiting scroll end plate 10. Specifically, as shown in fig. 4, the pressure control passage includes a first pressure control passage P1 and a second pressure control passage P2 extending substantially in a direction transverse to the axis of the compression mechanism, a first end of the first pressure control passage P1 is connected to the solenoid valve 30, and a second end opposite to the first end thereof communicates with the pressure control chamber CP, a first end of the second pressure control passage P2 is connected to the solenoid valve 30, and a second end opposite to the first end thereof communicates with the central compression chamber CO or at least one intermediate compression chamber adjacent to the central compression chamber CO.

More specifically, as shown in fig. 5a, the non-orbiting scroll end plate 10 is further formed at the second end of the second pressure control passage P2 with a second communication vertical hole P21 extending to the central compression chamber CO or at least one intermediate compression chamber close to the central compression chamber CO substantially in the axial direction of the compression mechanism, and the second pressure control passage P2 is communicated with the central compression chamber CO or at least one intermediate compression chamber close to the central compression chamber CO through the communication vertical hole P21. As shown in fig. 5b, the non-orbiting scroll end plate 10 is further formed at the second end of the first pressure control passage P1 with a first communication vertical hole P11 extending substantially in the axial direction of the compression mechanism. In addition, referring to fig. 2, the second side of the non-orbiting scroll end plate 10 is further formed with a side groove 19 extending outward from the piston port 12 in a direction transverse to the axial direction of the compression mechanism, the side groove 19 may be formed by notching the surface of the second side of the non-orbiting scroll end plate 10, and the side groove 19 is covered with a cover together with the piston port 12. The first pressure control passage P1 is connected to the side groove 19 through the first communication vertical hole P11 so as to communicate with the pressure control chamber CP.

The operation of the liquid discharge control mechanism of the scroll compressor will be described with reference to fig. 3a and 3 b. The controller is adapted to control the solenoid valve 30 and thus the piston 51 arranged in the discharge channel. As shown in fig. 3a, when there is too much liquid in the compression chamber of the scroll compressor and drainage is required (flooded condition), the controller sets the solenoid valve 30 to a first state (i.e., the solenoid valve 30 is energized) in which the solenoid valve 30 communicates the first pressure control passage P1 with the suction pressure region outside the compression mechanism, whereby the pressure control chamber CP communicates with the suction pressure region via the first pressure control passage P1 to obtain a pressure substantially equal to the suction pressure region. In other words, the upper end face of the piston 51 is subjected to a gas pressure applied by the pressure control chamber CP which is substantially equal to the pressure of the suction pressure area. And the liquid in the suction chamber CI is pushed and pressed by the scroll blades, contacts the lower end surface of the piston 51 via the liquid inlet 15, and applies a thrust force greater than the pressure of the suction pressure region to the lower end surface of the piston 51. Therefore, the lower end surface of the piston 51 is subjected to a thrust force greater than the pressure force of the upper end surface of the piston 51, the piston 51 moves upward to its open position by the pressure difference, the lower end surface of the piston 51 is separated from the seal seat at the bottom of the piston port 12, and the liquid in the suction chamber CI is discharged to the outside of the compression mechanism via the liquid inlet 15, the piston port 12, and the liquid inlet 14 in this order.

When the scroll compressor does not require draining (non-flooded condition), as shown in fig. 3b, the controller sets the solenoid valve 30 to a second state (i.e., the solenoid valve 30 is de-energized) in which the solenoid valve 30 communicates the first pressure control passage P1 with the second pressure control passage P2, whereby the pressure control chamber CP communicates with the central compression chamber CO or an intermediate compression chamber near the central compression chamber CO via the first and second pressure control passages P1, P2, thereby achieving a high pressure close to the discharge pressure. In other words, the upper end surface of the piston 51 is subjected to a high-pressure gas pressure close to the exhaust pressure applied by the pressure control chamber CP. And the lower end surface of the piston 51 is subjected to a pressure of low-pressure gas in the suction chamber CI. Therefore, the lower end surface of the piston 51 is subjected to a pressure lower than that of the upper end surface of the piston 51, the piston 51 moves downward to its closed position under the action of the pressure difference, the lower end surface of the piston 51 engages with the seal seat at the bottom of the piston bore 12 and seals the liquid inlet 15, thereby isolating the suction chamber CI from the suction pressure region outside the compression mechanism, and the scroll compressor can perform a normal compression operation.

Although the liquid discharge passage is configured to communicate with the suction chamber CI in the embodiment of the present invention, it can be understood by those skilled in the art that the liquid discharge passage may be configured to communicate with an intermediate compression chamber C adjacent to the suction chamber CI among the plurality of intermediate compression chambers. Alternatively, the liquid discharge passage may be configured to include a first liquid discharge passage capable of communicating with the suction chamber CI and a second liquid discharge passage capable of communicating with an intermediate compression chamber C adjacent to the suction chamber CI among the plurality of intermediate compression chambers. Since the liquid discharge channel can selectively provide fluid communication between the suction chamber CI and a suction pressure region outside the compression mechanism and/or between at least one intermediate compression chamber C adjacent to the suction chamber CI and a suction pressure region outside the compression mechanism, the liquid in the compression chamber can be discharged outside the compression mechanism in a timely manner without experiencing or experiencing as little as possible pushing and squeezing of the scroll blades, thereby reducing impact of the liquid on the scroll blades and avoiding damage to the scroll blades.

In order to allow the liquid in the suction chamber CI to be discharged more quickly through the liquid discharge channel upon liquid discharge, it is preferred that the side wall of the piston 51 does not cover the liquid outlet 14 when the piston 51 is in its open position, thereby increasing the flow area of the liquid discharge channel so that the liquid can flow out more smoothly through the liquid outlet 14.

Further, in order to ensure effective control of the pressure control chamber CP, it is preferable that a sealing member 511, such as an O-ring, is further provided between the piston 51 and the piston bore 12, and the sealing member 511 is received in a sealing groove 512 formed in an outer side surface of the piston 51 to provide sealing between the outer side surface of the piston 51 and an inner side surface of the piston bore 12. In addition, no matter the piston 51 is in the optional position, sealing member 511 is located the top of liquid outlet 14 all the time to guarantee that the space above sealing member 511 is sealed isolated with the space of below all the time, also isolated with liquid outlet 14 and pressure control chamber CP, avoided liquid entering pressure control chamber CP from this, guaranteed the accurate and quick control of pressure control chamber CP to piston 51.

As will be appreciated by those skilled in the art, referring to fig. 2, two sets of drainage channels may be formed in the non-orbiting scroll end plate 10, which are generally symmetrically disposed on either side of the central axis of the compression mechanism, thereby allowing the compression mechanism to be balanced when drained. Additionally, at least one set of drainage passages may include one or more piston ports 12 (e.g., as shown in FIG. 1, each set of drainage passages includes two piston ports 12), with one piston 51 disposed in each piston port 12. Each piston port in a set of drainage channels is connected by a single liquid outlet 14 in the form of an elongated slot. The second side surface of the non-orbiting scroll end plate 10 is also recessed to form a communication groove 13 to communicate the pressure control chambers CP in the respective piston bore 12 in each group of the liquid discharge passages. The cover member may be configured as a plurality of cover members that cover each piston hole passage 12 and the communication groove 13 in each set of liquid discharge passages, respectively, or as a single cover member that covers all the piston hole passages 12 and the communication grooves 13 in one set of liquid discharge passages. Since the pressure control chambers CP in all the piston ports 12 in each set of liquid discharge passages are communicated, only one side groove 19 and a corresponding one of the first pressure control passages P1 need be provided for each set of liquid discharge passages. And for the whole compression mechanism, only one second pressure control channel P2 and one electromagnetic valve 30 are needed to realize synchronous control of a plurality of pistons. The design of the piston pore passages and the pistons further increases the flow area of the liquid discharge channel, so that the liquid can be discharged out of the compression mechanism as soon as possible.

As is known to those skilled in the art, especially for large displacement scroll compressors, slugging conditions typically occur during compressor startup. Therefore, the utility model discloses still provide a flowing back control method for scroll compressor to the liquid in the compression chamber is discharged effectively during the start-up of compressor, avoids the start liquid attack damage of compressor.

Specifically, first, at the start of the scroll compressor, the solenoid valve 30 is switched to the first state (the solenoid valve 30 is energized), at which time the first pressure control passage P1 communicates with the suction pressure region outside the compression mechanism, and the piston 51 moves up to its open position. Subsequently, the solenoid valve is maintained in the first state for a predetermined time, which is a starting time set according to the model of the compressor, for example, set to 3 to 5 minutes, and the liquid in the suction chamber CI is discharged to the suction pressure region outside the compression mechanism through the liquid discharge passage. After the solenoid valve is maintained in the first state for a predetermined time, the solenoid valve 30 is switched to the second state (the solenoid valve 30 is de-energized), at which time the first pressure control passage P1 is communicated with the second pressure control passage P2, the piston 51 moves down to its closed position, the liquid discharge passage no longer discharges liquid, and the compressor can operate normally.

In order to carry out the flowing back more in time and accurately, the utility model discloses still provide another kind of flowing back control method for scroll compressor, wherein, scroll compressor still includes flowing back detection mechanism, and flowing back detection mechanism detects or detects continuously with scheduled time interval, carries out the flowing back when detecting that scroll compressor is in the liquid-carrying operating mode. The detection method of the liquid discharge detection mechanism is, for example: the compressor is judged to be in the liquid-carrying condition when the current of the motor is detected to be high and exceed the threshold value, or when the temperature of the compression mechanism (such as the temperature of the central compression cavity CO) is detected to be high and exceed the threshold value.

Specifically, when the liquid discharge detection mechanism detects that the scroll compressor is in the liquid-carrying condition, the controller switches the solenoid valve to and maintains the first state in which the first pressure control passage P1 is communicated with the suction pressure region outside the compression mechanism, the piston 51 moves up to its open position, and the liquid in the suction chamber CI is discharged to the suction pressure region outside the compression mechanism through the liquid discharge passage. When the liquid discharge detection mechanism detects that the scroll compressor is in a non-liquid-carrying working condition, the electromagnetic valve 30 is switched to a second state, the first pressure control channel P1 is communicated with the second pressure control channel P2 in the second state, the piston 51 moves downwards to a closing position, the liquid discharge channel does not discharge liquid any more, and the compressor can normally run.

Utilize according to the utility model discloses a flowing back control method, flowing back passageway can carry out effective flowing back as required, is favorable to reducing the start moment of torsion of compressor very much, reduces motor impact load, has guaranteed compressor job stabilization nature and reliability, has prolonged the life of motor effectively.

Furthermore, although the liquid discharge channel and the liquid discharge control mechanism are provided in the fixed scroll in the embodiment of the present invention, those skilled in the art can understand that the liquid discharge channel and the liquid discharge control mechanism may be provided in the movable scroll and obtain similar effects.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the precise embodiments described and illustrated herein, and that various changes may be made therein by those skilled in the art without departing from the scope of the invention as defined in the appended claims. It should also be understood that features of the various embodiments may be combined with each other or may be omitted without departing from the scope of the claims.

Claims (15)

1. A compression mechanism comprising:

an orbiting scroll having an orbiting scroll end plate and an orbiting scroll blade formed at one side of the orbiting scroll end plate;

a fixed scroll having a fixed scroll end plate and a fixed scroll blade formed at a first side of the fixed scroll end plate, the movable scroll blade and the fixed scroll blade engaging with each other to form a suction chamber, a central compression chamber, and a plurality of intermediate compression chambers between the movable scroll and the fixed scroll;

characterized in that the compression mechanism is provided with a drainage channel comprising a first drainage channel configured to selectively provide fluid communication between the suction chamber and the exterior of the compression mechanism and/or a second drainage channel configured to selectively provide fluid communication between an intermediate compression chamber of the plurality of intermediate compression chambers, which is adjacent to the suction chamber, and the exterior of the compression mechanism.

2. The compression mechanism of claim 1, wherein a piston is disposed within the drainage channel that is movable between an open position providing the fluid communication and a closed position not providing the fluid communication.

3. The compression mechanism of claim 2, wherein the drainage passage is disposed in the non-orbiting scroll end plate and is configured as a piston bore extending from a second side of the non-orbiting scroll end plate opposite the first side to the first side, the piston bore having a liquid inlet in communication with the suction chamber or with the intermediate compression chamber proximate the suction chamber, and the piston bore having a liquid outlet in communication with an exterior of the compression mechanism on a side of the piston bore.

4. The compression mechanism as recited in claim 3 wherein a cover is disposed on the second side of the non-orbiting scroll end plate, the cover covering and sealing the piston bore such that a pressure control chamber is formed within the piston bore in an area between the cover and the piston.

5. The compression mechanism according to claim 4, further comprising a solenoid valve provided outside the non-orbiting scroll, a first pressure control passage extending substantially in a direction transverse to an axial direction of the compression mechanism being formed in the non-orbiting scroll end plate, the first pressure control passage being connected to the solenoid valve and communicating with the pressure control chamber.

6. The compression mechanism as claimed in claim 5, wherein a second pressure control passage extending substantially in a direction transverse to an axial direction of the compression mechanism is further formed in the non-orbiting scroll end plate, the second pressure control passage being connected to the solenoid valve and communicating with an intermediate compression chamber adjacent to the central compression chamber among the central compression chamber or the plurality of intermediate compression chambers.

7. The compression mechanism as recited in claim 6 wherein said solenoid valve has a first state and a second state, said solenoid valve being in said first state to communicate said first pressure control passage with an exterior of said compression mechanism during a flooded condition of said compression mechanism and said solenoid valve being in said second state to communicate said first pressure control passage with said second pressure control passage during a non-flooded condition of said compression mechanism.

8. The compression mechanism of any one of claims 4 to 7, wherein the drainage channels comprise two sets of drainage channels arranged substantially symmetrically on either side of a central axis of the compression mechanism.

9. The compression mechanism of claim 8, wherein at least one of the two sets of drainage passages includes a plurality of piston ports, and a communication groove is formed in the second side of the non-orbiting scroll end plate, the communication groove communicating with the pressure control chamber in each of the plurality of piston ports.

10. The compression mechanism as claimed in any one of claims 5 to 7, wherein a side groove extending outward from the piston port hole is formed at the second side of the non-orbiting scroll end plate, the side groove communicating with the first pressure control passage.

11. A compression mechanism according to any one of claims 4 to 7, wherein a seal is provided between the piston and the piston bore, the seal always sealing the liquid outlet from the pressure control chamber with the piston in any position.

12. A compression mechanism as claimed in any one of claims 3 to 7, wherein the base of the piston bore is formed with a sealing seat engageable with the lower end of the piston and forming a seal against the liquid inlet.

13. The compression mechanism of any one of claims 3-7, wherein the piston bore is configured to: a portion of the piston bore overlaps the non-orbiting scroll blade when viewed in an axial direction of the compression mechanism.

14. A scroll compressor, characterized by comprising the compression mechanism according to any one of claims 1 to 13.

15. The scroll compressor of claim 14, further comprising a controller adapted to control a solenoid valve of the compression mechanism disposed outside the non-orbiting scroll to control a piston disposed within the drain passage such that the drain passage provides the fluid communication during start-up of the scroll compressor or upon detection of the scroll compressor in a flooded condition.

Images