KR20180068642A - Scroll compressor - Google Patents

Abstract

A scroll compressor according to the present invention comprises: a casing; a rotating scroll; a non-swirl scroll formed with at least one bypass hole; a back pressure room assembly body forming a back pressure room; a first valve selectively opening and closing a flow path between the bypass hole and an interior space of the casing; and a second valve provided at the outside of the casing, and changing the pressure applied to a back pressure surface opposite to the bypass hole between both side surfaces of the first valve, wherein the back pressure room assembly body or the non-swirl scroll is formed with a middle pressure hole penetrating through an outer peripheral surface from the back pressure room, and a filter is provided in the middle pressure hole such that forging matters of the back pressure room can be prevented from being introduced into the flow path, which is for changing a capacity of the scroll compressor.

Description

[0001] SCROLL COMPRESSOR [0002]

The present invention relates to a scroll compressor, and more particularly to a capacity variable device of a scroll compressor.

The scroll compressor is provided with a non-orbiting scroll in the inner space of the casing. The non-orbiting scroll of the non-orbiting scroll and the orbiting scroll of the orbiting scroll are engaged with the orbiting scroll, To form a pair of two compression chambers.

The scroll compressor is widely used for compressing refrigerant in an air conditioner or the like because it can obtain a relatively high compression ratio as compared with other types of compressors, and smooth suction, compression, and discharge strokes of the refrigerant can be obtained and stable torque can be obtained.

The scroll compressor can be divided into a high-pressure type and a low-pressure type depending on the type of refrigerant being supplied to the compression chamber. In the high-pressure scroll compressor, the refrigerant is directly sucked into the suction chamber without passing through the inner space of the casing, and is discharged through the inner space of the casing. Thus, most of the inner space of the casing forms the discharge space of high pressure. On the other hand, in the low-pressure scroll compressor, the refrigerant is indirectly sucked into the suction chamber through the inner space of the casing, and the inner space of the casing is divided into the suction space which is the low pressure portion and the discharge space which is the high pressure portion by the high-

1 is a longitudinal sectional view of a conventional low-pressure scroll compressor.

As shown in the figure, a conventional low-pressure scroll compressor is provided with a drive motor 20 for generating a rotational force in an internal space 11 of a sealed casing 10, 30 are installed.

On the upper surface of the main frame 30, the orbiting scroll 40 is pivotally supported by a bearing (not shown), and the non-orbiting scroll 50 is engaged with the upper side of the orbiting scroll 40, Respectively.

The rotary shaft 25 is coupled to the rotor 22 of the drive motor 20 and the orbiting scroll 40 is eccentrically coupled to the rotary shaft 25. The non-orbiting scroll 50 is rotated Are coupled to each other.

A back pressure chamber assembly 60 for preventing floating of the non-orbiting scroll 50 due to the pressure of the compression chamber P during operation is coupled to the upper side of the non-orbiting scroll 50. [ The back pressure chamber assembly 60 is provided with a back pressure chamber 60a filled with refrigerant at an intermediate pressure.

The backside of the back pressure chamber assembly 60 is supported on the back side of the back pressure chamber assembly 60 and the inner space 11 of the casing 10 is separated into the suction space 11 as the low pressure portion and the discharge space 12 as the high pressure portion Pressure separating plate 15 is provided.

The high and low pressure separating plate 15 has an outer circumferential surface welded to the inner circumferential surface of the casing 10 and welded and a discharge hole 15a communicating with the discharge port 54 of the non-orbiting scroll 50 is formed at the center.

In the figure, reference numeral 13 denotes a suction pipe, reference numeral 14 denotes a discharge tube, reference numeral 18 denotes a subframe, reference numeral 21 denotes a stator, reference numeral 21a denotes a winding coil, reference numeral 41 denotes a long plate portion of the orbiting scroll, 52 is a non-orbiting wrap, 53 is an intake port, and 61 is a modulation ring for variable capacity.

In the scroll compressor of the related art, when the power is applied to the driving motor 20 and the rotating force is generated, the rotating shaft 25 transmits the rotating force of the driving motor 20 to the orbiting scroll 40.

Then, the orbiting scroll 40 is pivotally moved relative to the non-orbiting scroll 50 by the overhanging, and a pair of two compression chambers P are formed between the orbiting scroll 50 and the orbiting scroll 50, Suction, compression, and discharge.

At this time, a part of the refrigerant compressed in the compression chamber P moves from the intermediate pressure chamber to the back pressure chamber 60a through a back pressure hole (not shown), and the intermediate pressure refrigerant flowing into the back pressure chamber 60a So that the floating plate 65 constituting the back pressure chamber assembly 60 floats. The floating plate 65 is brought into close contact with the bottom surface of the high and low pressure separating plate 15 so that the suction space 11 and the discharge space 12 are separated from each other and the back pressure chamber pressure is set to the non- So that the compression chamber P between the non-orbiting scroll 50 and the orbiting scroll 40 can be kept airtight.

Here, the scroll compressor, like other compressors, can vary the compression capacity in accordance with the demand of the refrigerating machine to which the compressor is applied. For example, as shown in Fig. 1, a modulation ring 61 and a lift ring 62 are additionally provided on the rigid plate portion 51 of the non-orbiting scroll 50, and a modulation ring 61 is provided with a control valve 63 communicating with the back pressure chamber 60a and the first communication path 61a. A second communication path 61b is formed between the modulation ring 61 and the lift ring 62 and the modulation ring 61 floats between the modulation ring 61 and the non-orbiting scroll 50 A third communication path 61c is formed. One end of the third communication path 61c communicates with the intermediate compression chamber P and the other end communicates with the suction space 11 of the casing 10. [

In this scroll compressor, the control valve 63 closes the first communication path 61a and the second communication path 61b communicates with the suction space 11, as shown in FIG. 2A, so that the modulation ring 61 So that the third communication path 61c is kept closed.

2b, the control valve 63 communicates the first communication path 61a with the second communication path 61b so that the modulation ring 61 floats to the third communication path 61c, A part of the refrigerant in the intermediate compression chamber P leaks into the suction space 11 to reduce the compressor capacity.

However, the variable capacity device of the conventional scroll compressor is composed of the modulation ring 61, the lift ring 62, and the control valve 63 and has a large number of parts. In order to operate the modulation ring 61, The first communication passage 61a, the second communication passage 61b and the third communication passage 61c must be formed in the first and second communication passages 61 and 61 so that the structure of the modulation ring 61 is complicated.

The modulating ring 61 is formed in an annular shape and the control valve 63 is engaged with the coupling ring 61. However, Not only the weight of the modulation ring 61 is increased, but also it is difficult to rapidly raise the modulation.

The capacity variable device of the conventional scroll compressor is configured such that the flow path for lifting the modulation ring 61 is long and the refrigerant is introduced into the space between the modulation ring 61 and the lift ring 62, However, since the pressure of the back pressure chamber 60a still exists on the upper surface of the modulation ring 61, it is not easy to float the modulation ring 61 and the responsiveness of the valve is lowered accordingly, There is also a problem that can not be controlled.

Further, in the conventional capacity variable device of the scroll compressor, a bypass hole and a check valve for opening / closing the bypass hole can not be structurally structured, and when the over-compression occurs in the corresponding operation mode, .

In addition, since the control valve 63 is installed inside the casing 10, the size of the control valve 63 must be determined in consideration of the internal space of the casing 10, The degree of freedom in designing the valve 63 is low and the small size control valve 63 must be used in a limited space.

In addition, since the capacity variable device of the conventional scroll compressor is required to additionally include a terminal for supplying power to the control valve 63 in addition to a terminal for supplying power to the drive motor, the number of parts increases, And the manufacturing cost is increased.

In the capacity variable device of the conventional scroll compressor, since the control valve 63 is installed inside the casing 10, it is impossible to replace the control valve 63 when the control valve 63 fails, The entire compressor must be replaced.

When the control valve 63 is provided outside the casing 10, the capacity variable device of the conventional scroll compressor uses a connection pipe having a small inner diameter to provide a connection passage between the inside and the outside of the casing 10, The control valve 63 must be connected to each other so that the foreign matter may accumulate in the middle of the connection passage or flow into the control valve 63 and remain there. This may cause an error in the switching of the variable capacity mode or the reliability of the compressor as a whole.

It is an object of the present invention to provide a scroll compressor capable of reducing the manufacturing cost by simplifying the structure of the capacity variable device.

Another object of the present invention is to provide a scroll compressor capable of alleviating the restriction on parts constituting the capacity variable device.

It is another object of the present invention to provide a scroll compressor capable of easily supplying a power source for operating the capacity variable device.

Another object of the present invention is to provide a scroll compressor which can simplify the control of the capacity variable device and increase the responsiveness.

Another object of the present invention is to provide a scroll compressor in which a bypass hole and a check valve for opening and closing the bypass hole can be provided to prevent the efficiency of the compressor due to overpressure from being lowered.

Another object of the present invention is to provide a scroll compressor in which a control valve for varying the capacity is provided outside the casing to increase the degree of freedom in design.

Another object of the present invention is to provide a scroll compressor in which a control valve for varying the capacity can be applied as an inexpensive standard product, thereby reducing the manufacturing cost.

Another object of the present invention is to provide a scroll compressor in which a separate terminal for supplying power to the control valve is not required to be provided in the casing.

Another object of the present invention is to provide a scroll compressor capable of reducing the number of parts and assembling air by installing a check valve for bypassing the refrigerant in the compression chamber and installing the check valve between the non-orbiting scroll and the back pressure chamber assembly I am trying to provide.

It is another object of the present invention to provide a control valve that can be installed outside the casing to easily replace the control valve without replacing the compressor in the event of a failure of the control valve, And to provide a scroll compressor that can be firmly connected.

Another object of the present invention is to provide a scroll compressor capable of preventing foreign matter from flowing into a control valve and a connection passage connected to the control valve.

In order to accomplish the object of the present invention, there is provided a scroll compressor including a high-pressure separating plate separating an internal space of a casing into a high-pressure portion and a low-pressure portion, the scroll compressor comprising: And a valve capable of opening and closing the flow path is provided at an end of the flow path.

Here, the check valve may be provided in the middle of the flow passage and may be opened or closed according to the pressure difference of the intermediate pressure chamber.

The plurality of flow paths may be formed so as to communicate with each other, and the control valve may be provided at an end portion of the flow path communicating with the low pressure portion.

Further, in order to achieve the object of the present invention, A orbiting scroll provided in an inner space of the casing and performing a turning motion; A non-orbiting scroll in which at least one or more bypass holes are formed so as to form a compression chamber formed of a suction chamber, an intermediate pressure chamber, and a discharge chamber in engagement with the orbiting scroll and to bypass a portion of the refrigerant in the intermediate pressure chamber to the inner space of the casing; A back pressure chamber assembly provided on a back surface of the non-orbiting scroll to form a back pressure chamber so as to press the non-orbiting scroll in the orbiting scroll direction; A first valve selectively opening and closing a flow path between the bypass hole and the internal space of the casing; And a second valve provided outside the casing and varying a pressure applied to a back pressure surface opposite to the bypass hole on both sides of the first valve, An intermediate pressure hole penetrating from the back pressure chamber to the outer peripheral surface is formed, and a filter is provided in the intermediate pressure hole.

Here, the intermediate pressure hole may include: a first portion communicating with the back pressure chamber or the intermediate pressure chamber; And a second portion communicated from the first portion to the outer circumferential surface of the back pressure chamber assembly or the outer circumferential surface of the non-orbiting scroll, wherein the axial direction of the first portion and the axial direction of the second portion are formed to intersect with each other And the filter may be installed between the first part and the second part.

The second portion may have a stepped surface, and the filter may be supported on the stepped surface.

The intermediate pressure hole is coupled with a back pressure chamber or a connection pipe connecting the intermediate pressure chamber and the second valve. One side of the filter is supported by the connection pipe to be installed in the intermediate pressure hole. have.

In addition, a stepped surface is formed in the intermediate pressure hole, and the filter is disposed between the stepped surface and the end of the coupling pipe, so that both sides thereof can be supported.

The filter may be fixedly coupled to a distal end surface of the coupling tube.

A stepped groove larger than the intermediate pressure hole is formed on the bottom surface of the back pressure chamber, and the filter can be inserted into the stepped groove to be coupled.

The filter may include a fixing part formed in the annular shape and inserted into the stepped groove, a mesh part coupled to the fixing part to filter out foreign matter, and a support part extending from the fixing part and supporting the mesh part .

In the scroll compressor according to the present invention, since the check valve is provided in the bypass hole, the number of components is small and the control valve is provided at the end of the bypass hole, so that the bypass flow path for bypassing the refrigerant can be simplified. Thus, the variable capacity device can be easily manufactured.

Further, since the control valve is provided at the end portion of the flow path, when the refrigerant is switched from the power operation to the saving operation, the refrigerant has already reached the vicinity of the outlet end of the flow path and is in a standby state.

In addition, the position of the control valve can be shifted by using the communicating tube, so that the specification limit of the control valve can be relaxed. This makes it possible to increase the reliability of the capacity variable device.

In addition, a bypass hole for bypassing a part of the refrigerant to be compressed in the intermediate pressure chamber and a check valve for opening and closing the bypass hole can be provided, so that the efficiency of the compressor due to overcompression can be prevented in advance.

In addition, since the control valve for varying the capacity can be provided outside the casing to increase the degree of freedom in designing, the control valve can be applied as an inexpensive standard product, and the manufacturing cost can be reduced.

In addition, since it is not necessary to provide a separate terminal for supplying power to the control valve in the casing, the manufacturing cost can be reduced.

In addition, the check valve for bypassing the refrigerant in the compression chamber can be installed between the non-orbiting scroll and the back pressure chamber assembly, thereby reducing the number of components and the number of assemblies, thereby reducing manufacturing costs.

In addition, since the control valve can be provided outside the casing, the control valve can be easily replaced without replacing the compressor in the event of a failure of the control valve, and a scroll compressor .

In addition, when the control valve is provided outside the casing, the connecting passage between the inside and the outside of the casing and the control valve must be connected to each other by using a connecting pipe having a small inner diameter so that the foreign matter is accumulated in the middle of the connecting passage, It may flow into the valve and remain there. This may cause an error in the switching of the variable capacity mode or the reliability of the compressor as a whole. However, when the filter is installed in the connection passage as in the present invention, it is possible to prevent the foreign matter from being accumulated in the connection passage or the control valve, thereby maintaining the operational reliability and life of the compressor.

1 is a longitudinal sectional view showing a scroll compressor having a conventional capacity variable device,
FIG. 2A and FIG. 2B are longitudinal sectional views showing the power operation and the saving operation state using the capacity variable device in the scroll compressor according to FIG.
FIG. 3 is a longitudinal sectional view showing a scroll compressor having a capacity variable device according to the present invention. FIG.
FIG. 4 is a perspective view showing a scroll compressor having a capacity variable device according to FIG. 3,
FIG. 5 is a perspective view of the capacity variable device shown in FIG. 4,
FIG. 6 is a cross-sectional view schematically showing a connection state of a check valve and a control valve by assembling the capacity variable device according to FIG. 3;
7 is an exploded perspective view showing an embodiment of the filter according to the present invention,
8 to 10 are sectional views showing other embodiments of the filter according to the present invention,
FIG. 11A and FIG. 11B are schematic views showing the operation of the first valve assembly and the second valve assembly according to the operation mode of the compressor in FIG. 3, wherein FIG. 11A is a power mode and FIG. 11B is a saving mode,
12 is a perspective view in which another embodiment of the capacity variable device according to the present invention is exploded,
FIGS. 13A and 13B are enlarged longitudinal sectional views of embodiments of the first valve assembly in the capacity variable device according to FIG. 3;
FIGS. 14A and 14B are schematic views showing the operation of the first valve assembly and the second valve assembly according to the operation mode of the compressor in FIG. 12, wherein FIG. 14A is a power mode and FIG. 14B is a saving mode.

Hereinafter, a scroll compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

FIG. 3 is a vertical sectional view showing a scroll compressor having a capacity variable device according to the present invention, FIG. 4 is a perspective view showing a scroll compressor having a capacity variable device according to FIG. 3, and FIG. FIG. 6 is a cross-sectional view schematically showing a connection state of a check valve and a control valve by assembling the capacity variable device according to FIG. 3; FIG.

3, the scroll compressor according to the present embodiment is installed on the upper side of the non-orbiting scroll (hereinafter, mixed with the second scroll) 150, which will be described later, Pressure separation plate 115 into the suction space 111, which is a low-pressure portion, and the discharge space 112, which is a high-pressure portion. Here, the suction space 111 corresponds to the lower space of the high-low pressure separation plate 115, and the discharge space 112 corresponds to the space above the high-low pressure separation plate.

The suction pipe 113 communicating with the suction space 111 and the discharge pipe 114 communicating with the discharge space 112 are fixed to the casing 110 so that the refrigerant can be sucked into the inner space of the casing 110, (Not shown).

A driving motor 120 including a stator 121 and a rotor 122 is provided in the suction space 111 of the casing 110. The stator 121 is fixed to the inner wall surface of the casing 110 in a heat shrinking manner and a rotating shaft 125 is inserted and coupled to the center portion of the rotor 122. The coil 121a is wound on the stator 121 and the coil 121a is electrically connected to an external power source through a terminal 119 which is coupled to the casing 110 as shown in FIGS.

The lower side of the rotating shaft 125 is rotatably supported by an auxiliary bearing 117 provided below the casing 110. The auxiliary bearing 117 is supported by the lower frame 118 fixed to the inner surface of the casing 110 to stably support the rotary shaft 125. [ The lower frame 118 can be welded to the inner wall surface of the casing 110, and the bottom surface of the casing 110 is used as an oil storage space. The oil stored in the oil storage space is transferred to the upper side by the rotation shaft 125 or the like, so that the oil enters the drive unit and the compression chamber to smooth the lubrication.

The upper end of the rotary shaft 125 is rotatably supported by the main frame 130. The main frame 130 is fixed to the inner wall surface of the casing 110 like the lower frame 118 and the main bearing part 131 protruding downward is formed on the bottom surface of the main frame 130. Inside the main bearing part 131, The rotation shaft 125 is inserted. The inner wall surface of the main bearing portion 131 functions as a bearing surface and supports the rotating shaft 125 together with the above-described oil so as to be smoothly rotated.

An orbiting scroll (hereinafter, mixed with the first scroll) 140 is disposed on the upper surface of the main frame 130. The first scroll 140 includes a first hard plate 141 having a substantially disk shape and a orbiting wrap (hereinafter referred to as a first wrap) 142 formed in a spiral shape on one side of the first hard plate 141 . The first wrap 142 forms the compression chamber P together with the second wrap 152 of the second scroll 150 to be described later.

The first rigid plate 141 of the first scroll 140 is swiveled while being supported by the upper surface of the main frame 130. The first rigid plate 141 and the main frame 130, (136) is provided to prevent rotation of the first scroll (140).

A boss 143 is formed in the bottom surface of the first rigid plate 141 of the first scroll 140 to receive the rotation shaft 125. The rotational force of the rotation shaft 125 is transmitted to the first scroll 140 through the boss 143, And is driven to rotate.

The non-orbiting scroll 150 (hereinafter, mixed with the second scroll) engaging with the first scroll 140 is disposed on the upper portion of the first scroll 140. Here, the second scroll 150 is installed to move up and down with respect to the first scroll 140. More specifically, a plurality of guide pins (not shown) fitted to the main frame 130 are disposed on the second scroll 150 on the upper surface of the main frame 130 while being inserted into a plurality of guide holes (not shown) formed on the outer periphery of the main frame 130.

The upper surface of the body portion of the second scroll 150 is formed in a circular plate shape to form a second longitudinal plate portion 151. The lower end of the second longitudinal plate portion 151 is connected to the first scroll 140 of the first scroll 140, And a second wrap 152 engaging with the second rib 142 is formed in a spiral shape.

A suction port 153 for sucking refrigerant existing in the suction space 111 is formed in a side surface of the second scroll 150 and a discharge port 154 for discharging the compressed refrigerant is disposed in a substantially central portion of the second hard plate 151 Is formed.

As described above, the first lap 142 and the second lap 152 form a plurality of compression chambers P, and the compression chambers are swiveled toward the discharge ports 154 and the volume thereof is reduced to compress the refrigerant. Therefore, the pressure in the compression chamber adjacent to the suction port 153 is minimized, the pressure in the compression chamber communicating with the discharge port 154 becomes the maximum, and the pressure in the compression chamber existing therebetween becomes equal to the suction pressure And the discharge pressure of the discharge port 154, as shown in FIG. The intermediate pressure is applied to the back pressure chamber 160a to be described later and presses the second scroll 150 toward the first scroll 140. The intermediate pressure thus communicates with one of the regions having the intermediate pressure, The back pressure hole 151a is formed in the second hard plate portion 151. [

A back pressure plate 161 constituting a part of the back pressure chamber assembly 160 is fixed to the upper portion of the second longitudinal plate portion 151 of the second scroll 150. The back pressure plate 161 is formed in a substantially annular shape and has a support plate portion 162 which is in contact with the second longitudinal plate portion 151 of the second scroll 150. The support plate portion 162 has an annular plate shape with an empty center and a plate side back pressure hole 161d communicating with the scroll side back pressure hole 151a is formed to penetrate the support plate portion 162. [

First and second annular walls 163 and 164 are formed on the upper surface of the support plate 162 to surround the inner and outer circumferential surfaces of the support plate 162. The outer peripheral surface of the first annular wall 163, the inner peripheral surface of the second annular wall 164, and the upper surface of the support plate 162 form an annular back pressure chamber 160a.

Above the back pressure chamber 160a, there is provided a floating plate 165 which forms the upper surface of the back pressure chamber 160a. A sealing end 166 is provided at the upper end of the inner space of the floating plate 165. The sealing end 166 is formed to protrude upward from the surface of the floating plate 165, and the inner diameter of the sealing end 166 is formed so as not to cover the intermediate discharge port 167. The sealing end portion 166 is in contact with the lower surface of the high-low pressure separating plate 115 to seal the discharged refrigerant to be discharged into the discharge space 112 without leaking into the suction space 111.

Reference numeral 156 in the drawings denotes a bypass valve for opening / closing a discharge bypass hole for bypassing a part of the refrigerant compressed in the intermediate pressure chamber to prevent an overpressure shaft. Reference numeral 159 denotes a bypass valve for circulating the refrigerant discharged into the discharge space into the compression chamber The check valve is closed.

The scroll compressor according to this embodiment operates as follows.

That is, when electric power is applied to the stator 121 side, the rotation shaft 125 rotates. The first scroll 140 coupled to the upper end of the rotary shaft 125 rotates relative to the second scroll 150 as the rotary shaft 125 rotates, The plurality of compression chambers P formed between the laps 142 move to the discharge port 154 side, and the refrigerant is compressed.

When the compression chamber P is communicated with the scroll side back pressure hole (not shown) before reaching the discharge port 154, a part of the refrigerant flows into the plate side back pressure hole (not shown) formed in the support plate portion 162, The intermediate pressure is applied to the back pressure chamber 160a formed by the back pressure plate 161 and the floating plate 165. [ As a result, the back pressure plate 161 is pressed downward, and the floating plate 165 is pressed upward.

Here, since the back pressure plate 161 is coupled to the second scroll 150 by bolts, the intermediate pressure of the back pressure chamber 160a also affects the second scroll 150. However, since the second scroll 150 is already in contact with the first hard plate 141 of the first scroll 140 and can not move downward, the floating plate 165 moves upward. The floating plate 165 prevents the refrigerant from leaking from the discharge space 112 into the suction space 111 while the sealing end 166 is in contact with the lower end of the high and low pressure separator plate 115. The pressure of the back pressure chamber 160a pushes the second scroll 150 toward the first scroll 140 to block the leakage between the first scroll 140 and the second scroll 150. [

When the capacity variable device is applied to the scroll compressor according to the present embodiment, the second longitudinal plate portion 151 of the second scroll 150 is provided with a capacity varying bypass hole (hereinafter referred to as a bypass hole 151b) is formed to pass from the intermediate pressure chamber to the back surface. The bypass holes 151b are formed on both sides at 180 DEG intervals so that the intermediate pressure refrigerant of the same pressure in the inner and outer pockets can be bypassed. However, when the lap length of the first lap 142 is asymmetrical by 180 degrees with respect to the lap length of the second lap 152, since the same pressure is formed at the same crank angle between the inner pocket and the outer pocket, Only one hole 151b may be formed at the same crank angle or both may be communicated.

A check valve 155 is installed at the end of the bypass hole 151b to selectively open and close the bypass hole 151b. The check valve 155 constitutes the first valve assembly and may be formed as a piston valve that is opened or closed in accordance with the pressure of the intermediate pressure chamber.

4 and 5, the back pressure plate 161 according to the present embodiment is provided with a through hole 161 which penetrates from the upper surface constituting the back pressure chamber 160a to the outer circumferential surface of the back pressure plate 161, An intermediate pressure hole 168 is formed so as to be guided to the first connection pipe 183a to be described later.

A plurality of valve spaces 161a are formed in the bottom surface of the back pressure plate 161 so that the piston valves 155 selectively opening and closing the bypass holes 151b are slid in the axial direction, .

A differential pressure space 161b having a predetermined volume is formed on one side of the valve space 161a in the axial direction with a piston valve 155 constituting the first valve assembly interposed therebetween on the back side of the piston valve 155 .

The differential pressure space 161b is formed on both sides with a phase difference of 180 degrees with the valve space 161a. The differential pressure spaces 161b are formed in the connecting channel grooves 161c formed on the bottom surface of the back pressure plate 161, Respectively. In this case, as shown in Fig. 5, both ends of the connecting flow path groove 161c are formed to be inclined toward the respective differential pressure spaces 161b. The transverse sectional area of the differential pressure space 161b is formed to be larger than the transverse sectional area of the bypass hole 151b. The connection channel groove 161c is overlapped with the gasket 158 provided on the upper surface of the non-orbiting scroll 150 so that the connection channel groove 161c is sealed.

On the other hand, although not shown in the drawings, the valve space, the differential pressure space, and the discharge groove are not formed on the bottom surface of the back pressure plate, but may be formed on the upper surface of the non-orbiting scroll as in the above embodiment. In this case, the connecting passage groove may also be formed on the upper surface of the non-orbiting scroll.

The refrigerant discharged from the intermediate compression chamber through each bypass hole 151b is exhausted to the suction space 11 of the casing 110 when each piston valve 155 is opened on the bottom surface of the back pressure plate 161. [ The discharge groove 161d is formed independently of each of the back pressure holes 161a. As a result, both the bypass holes 151b communicate independently with the suction space 111 of the casing 110 through the respective discharge grooves 161d, thereby bypassing the compression chamber through both of the bypass holes 151b The refrigerant is discharged to the suction space 111 of the casing 110 immediately without being merged into one place. Thus, the refrigerant bypassed in the compression chamber can be prevented from being heated by the refrigerant in the back pressure chamber 160a. In addition, when the refrigerant bypassed from the compression chamber to the suction space 111 of the casing 110 is heated, it is possible to suppress the decrease in the suction volume due to an increase in the volume of the refrigerant.

The discharge groove 161d is formed in the radial direction from the inner peripheral surface of the valve space 161a toward the outer peripheral surface of the back pressure plate 161. [ The discharge groove 161d is formed by opening the outer peripheral surface of the discharge groove 161d so as to communicate with the inner space of the casing 110. [

In addition, a differential pressure hole 161e is formed in the middle of the coupling channel groove 161c to connect a third coupling pipe 183c to be described later. However, the differential pressure hole 161e may be directly connected to either one of the differential pressure spaces 161b. The differential pressure hole 161e can be connected to the control valve 180 constituting the second valve assembly through the third connection pipe 183c.

In this case, the control valve 180 constituting the second valve assembly may be installed in the internal space of the casing 110, which is formed of a solenoid valve. However, in order to increase the degree of freedom in designing the control valve 180, It may be preferable to be installed outside.

The control valve 180 is fixedly coupled to the outer circumferential surface of the casing 110 using a bracket 180a. However, in some cases, the control valve 180 may be directly welded to the casing 110 without using a separate bracket.

As shown in FIG. 6, the control valve 180 is a solenoid valve having a power supply unit 181 for selectively operating the mover 181b depending on whether an external power source is connected thereto.

The power source unit 181 is provided with a mover 181b inside a coil 181a to which power is supplied and a return spring 181c at one end of the mover. The mover 181b is coupled with a switching valve 186 that connects the first inlet / outlet 185a and the third inlet / outlet 185c to be described later or connects the second inlet / outlet 185b and the third inlet / outlet 185c . Thus, when power is applied to the coil 181a, the mover 181b and the valve 186 coupled to the mover 181b move in the first direction (discharge hole closing direction) and the corresponding connection pipe 183a While the power supply is turned off, the mover 181b returns to the second direction (discharge hole opening direction) by the return spring 181c, and the other connection pipes 183b and 183c ). Thereby, the refrigerant directed to the piston valve 155, which is a check valve, is switched according to the operation mode of the compressor.

One side of the power supply unit 181 is coupled with a valve unit 182 which is operated by the power supply unit 181 and switches the flow direction of the refrigerant.

The valve 182 may be slidably inserted into the valve housing 185 coupled to the power supply 181 and the switch valve 186 extending to the mover 181b of the power supply 181. Of course, depending on the configuration of the power supply unit 181, the switching valve 186 may be rotated without being reciprocated to change the flow direction of the refrigerant. However, in the present embodiment, a linear reciprocating valve will be mainly described.

The valve housing 185 is formed into a long cylindrical shape, and three outlets are formed along the longitudinal direction. The first inlet 185a is connected to the back pressure chamber 160a through a first connection pipe 183a to be described later and the second inlet 185b is connected to the back pressure chamber 160a through a second connection pipe 183b And the third inlet port 185c is connected to the differential pressure space 161b formed on one side of the piston valve 155 through a third connection pipe 183c to be described later. In the drawing, the first inlet / outlet 185a and the second inlet / outlet 185b are located on both sides and the third inlet / outlet 185c is located in the middle. However, this may vary depending on the configuration of the valve.

In order for the first inlet 185a of the control valve 180 to be connected to the back pressure chamber 160a through the first connection pipe 183a, 2 scroll 150 is to be formed. The intermediate pressure hole 168 may be formed to penetrate from the bottom surface of the back pressure chamber 160a to the outer circumferential surface of the back pressure plate 161. [

The valve 182 is coupled with a connection portion 183 which is coupled through the casing 110 and transfers the refrigerant converted by the valve portion 182 to the differential pressure space 161b.

The connection part 183 is provided with a first connection pipe 183a, a second connection pipe 183b and a third connection pipe 183c for selectively injecting an intermediate or suction pressure refrigerant into the first valve assembly 170, Lt; / RTI >

The first connection pipe 183a, the second connection pipe 183b and the third connection pipe 183c are both welded to the casing 110 through the casing 110. Each connection pipe may be formed of the same material as the casing 110, but may be formed of a material different from that of the casing. In the case of materials other than the casing, it is also possible to weld the intermediate member in consideration of the welding with the casing.

The connecting pipes 183a, 183b, and 183c may be individually welded through the casing 110, but this is not preferable in view of the fact that the diameters of the connecting pipes are not large. Accordingly, after coupling members are coupled to the casing 110, coupling pipes can be assembled to the inner and outer surfaces of the coupling members, respectively. In this case, it may be preferable that a part of each connection pipe is previously coupled to one side of the connection member to connect the connection member to the casing, and then the remaining connection pipes are connected to the other side of the connection member.

For example, as shown in FIG. 4, the connecting member 184 is formed in a cylindrical shape, and three connecting pipes 183a, 183b, and 183c are all inserted into the connecting member 184, or two connecting members 183a, (184) to the casing (110). In this case, after the coupling member 184 is coupled to the casing 110, an external force is applied to the coupling member 184 so that the coupling member 184 is brought into close contact with the coupling pipes 183a, 183b, and 183c The connection member 184 is welded between the connection pipes 183a, 183b and 183c or the connection pipe 184 is welded to the connection pipes 183a, 183b and 183c by applying an external force to the connection pipe 184 The connecting member 184 may be welded to the coupling pipe 184 by inserting the connecting member 184 into the casing 110.

One end of the first connection pipe 183a is connected to the first inlet / outlet 185a of the valve housing 185 and the other end is connected to the intermediate pressure hole 168 communicating with the back pressure chamber 160a. One end of the second connection pipe 183b is connected to the second inlet / outlet 185b of the valve housing 185 and the other end is connected to the suction space 111 of the casing 110, respectively. One end of the third connecting pipe 183c is connected to the third inlet / outlet 185c of the valve housing 185 and the other end is connected to the differential pressure hole 161e.

The intermediate pressure hole 168 has a vertical portion 168a formed at a predetermined depth in the axial direction on the bottom surface of the back pressure chamber 160a and penetrates to the outer peripheral surface of the back pressure plate 161 at the lower end of the vertical portion 168a The horizontal portion 168b may be formed. The vertical portion 168a may be referred to as a first portion, and the horizontal portion 168b may be referred to as a second portion. A connection pipe insertion groove 168c may be formed at an end of the horizontal portion 168b so that one end of a first connection pipe 183a to be described later can be inserted.

The intermediate pressure hole 168 may be provided with a filter 190 for preventing foreign matter remaining in the back pressure chamber 160a from entering the intermediate pressure hole 168. [ The filter 190 may be formed in the shape of a disk having a plurality of fine holes and may be inserted in the middle of the intermediate pressure hole 168.

FIG. 7 is an exploded perspective view showing an embodiment of the filter according to the present invention, and FIGS. 8 to 10 are sectional views showing another embodiment of the filter according to the present invention.

7 and 8, in the intermediate pressure hole 168 according to the present embodiment, the connection pipe insertion groove 168c is formed at the end portion of the horizontal portion 168b, which is in contact with the vertical portion 168a, 168d are formed. Therefore, one side of the filter 190 is supported on the stepped surface 168d, and the other side of the filter 190 is inserted into the first connection pipe 183a, which will be described later, The filter 190 may be supported between the first connection pipe 183a and the stepped surface 168d.

Alternatively, as shown in FIG. 9, the filter 190 is formed in a circular plate shape having an annular coupling portion 191 at its rim, and the annular coupling portion 191 is press-fitted into the end of the first coupling pipe 183a It is possible. A mesh portion 192 may be formed on one side of the annular coupling portion 191.

10, the filter 190 is provided with a stepped groove 168e extending from the vertical portion 168a of the intermediate pressure hole 168 at the inlet of the intermediate pressure hole 168, that is, at the end of the bottom surface of the back pressure chamber 160a. ) Can be formed and inserted. In this case, the filter 190 includes an insertion portion 193 formed in an annular shape and inserted into the stepped groove 168e, a mesh portion 194 coupled to the insertion portion 193 to filter out foreign matter, And a support part 195 extending from the mesh part 193 to support the mesh part 194. [

Considering that the refrigerant moves from the back pressure chamber 160a to the first connection pipe 183a, the support portion 195 may be provided with a first connection pipe 180a rather than the back pressure chamber 160a with respect to the mesh portion 194, (183a) side can stably support the mesh portion (194).

The valve 182 is coupled with a connection portion 183 which is coupled through the casing 110 and transfers the refrigerant converted by the valve portion 182 to the differential pressure space 161b.

The connection part 183 is provided with a first connection pipe 183a, a second connection pipe 183b and a third connection pipe 183c for selectively injecting an intermediate or suction pressure refrigerant into the first valve assembly 170, Lt; / RTI >

The first connection pipe 183a, the second connection pipe 183b and the third connection pipe 183c are both welded to the casing 110 through the casing 110. Each connection pipe may be formed of the same material as the casing 110, but may be formed of a material different from that of the casing. In the case of materials other than the casing, it is also possible to weld the intermediate member in consideration of the welding with the casing.

The connecting pipes 183a, 183b, and 183c may be individually welded through the casing 110, but this is not preferable in view of the fact that the diameters of the connecting pipes are not large. Accordingly, after coupling members are coupled to the casing 110, coupling pipes can be assembled to the inner and outer surfaces of the coupling members, respectively. In this case, it may be preferable that a part of each connection pipe is previously coupled to one side of the connection member to connect the connection member to the casing, and then the remaining connection pipes are connected to the other side of the connection member.

For example, as shown in FIG. 4, the connecting member 184 is formed in a cylindrical shape, and three connecting pipes 183a, 183b, and 183c are all inserted into the connecting member 184, or two connecting members 183a, (184) to the casing (110). In this case, after the coupling member 184 is coupled to the casing 110, an external force is applied to the coupling member 184 so that the coupling member 184 is brought into close contact with the coupling pipes 183a, 183b, and 183c The connection member 184 is welded between the connection pipes 183a, 183b and 183c or an external force is applied to the connection member 184 so as to be in close contact with the connection pipes 183a, 183b and 183c The connecting member 184 may be welded to the coupling pipe 184 by inserting the connecting member 184 into the casing 110.

One end of the first connection pipe 183a is connected to the first inlet / outlet 185a of the valve housing 185 and the other end is connected to the intermediate pressure hole 168 communicating with the back pressure chamber 160a. One end of the second connection pipe 183b is connected to the second inlet / outlet 185b of the valve housing 185 and the other end is connected to the suction space 111 of the casing 110, respectively. One end of the third connecting pipe 183c is connected to the third inlet / outlet 185c of the valve housing 185 and the other end is connected to the differential pressure hole 161e.

Reference numeral 119 in the drawings denotes a terminal, 155a is an opening / closing surface, 155b is a back pressure surface, 156 is a bypass valve, 157 is an O-ring, 161f is a plate side back pressure hole, 165 is a floating plate, 187 is an O-ring, 187f is an O-ring, 187f is a seal for inserting an O-ring, 187a is an O-ring, 187b is an O- Home.

The process of varying the capacity of the compressor in the scroll compressor according to the present invention operates as follows. 11A and 11B are schematic views showing the operation of the check valve and the valve assembly according to the operation mode of the compressor in FIG. 3, wherein FIG. 11A is a power mode and FIG. 11B is a saving mode.

11A, when the compressor operates in the power mode, the refrigerant of intermediate pressure is introduced into the differential pressure hole 161e through the first connection pipe 183a and the third connection pipe 183c by the valve assembly 180 , And the refrigerant flowing into the differential pressure hole 161e flows into the differential pressure spaces 161b through the coupling flow path groove 161c.

Then, the pressure in the differential pressure space 161b pressurizes the back pressure surface 155b of the piston valve 155 while forming the intermediate pressure. At this time, since the lateral cross-sectional area of the differential pressure space 161b is formed wider than the cross-sectional area of the bypass hole 151b, the both piston valves 155 are pressed against the pressure of the differential pressure space 161b, (151b).

Then, the refrigerant in the compression chamber is not leaked to both of the bypass holes 151b, thereby continuing the power operation.

On the other hand, when the compressor operates in the saving mode as shown in FIG. 11B, the refrigerant of the suction pressure is supplied to the differential pressure hole 161e through the second connection pipe 183b and the third connection pipe 183c by the valve assembly 180 And the refrigerant flowing into the differential pressure hole 161e flows into both the differential pressure spaces 161b through the coupling flow path groove 161c.

Then, the pressure in the differential pressure space 161b pressurizes the back pressure surface 155b of the piston valve 155 while forming the suction pressure. At this time, since the pressure of the intermediate compression chamber is formed higher than the pressure of the differential pressure space 161b, both piston valves 155 are pushed by the pressure of the intermediate compression chamber and rise respectively.

Then, as both the bypass holes 151b are opened and the refrigerant flows out into the suction space 111 of the casing 110 through the respective discharge grooves 161d in the respective intermediate compression chambers, the compressor performs a saving operation do.

In this way, a part of the refrigerant compressed in the intermediate pressure chamber at the time of overpressure can be bypassed, thereby increasing the efficiency of the compressor.

In addition, since the valve for opening and closing the bypass passage of the refrigerant is constituted by the piston valve operated by the small pressure change and is disposed between the non-orbiting scroll and the back pressure plate, the operation mode of the compressor can be quickly switched.

Further, since the first valve assembly is installed at the end of the discharge passage for the refrigerant, when the refrigerant is switched from the power operation to the saving operation, the refrigerant has already reached the outlet end of the flow passage and is in a standby state. Can be switched.

Further, by simplifying the connecting portion connecting the first valve assembly, which is a check valve, and the second valve assembly, which is a control valve, the number of components is reduced, and the flow path for bypassing the refrigerant is also simple and easy to manufacture. And the reliability of the switching operation of the first valve assembly can be enhanced.

In addition, by providing the second valve assembly outside the casing, it is possible to lower the specification limit for the second valve assembly compared to installing the second valve assembly inside the casing, thereby allowing the second valve assembly to be a standardized product And the manufacturing cost can be reduced accordingly.

Further, by providing the second valve assembly on the outside of the casing, it is not necessary to additionally provide a terminal for supplying power, unlike the case where the second valve assembly is installed in the casing, thereby preventing the number of components and the number of assembling operations accordingly So that the manufacturing cost can be reduced.

Meanwhile, another embodiment of the scroll compressor having the capacity variable device according to the present invention is as follows.

That is, in the above-described embodiment, a check valve is provided between the non-orbiting scroll and the back pressure plate, and a control valve for controlling the check valve is provided outside the casing and connected by a plurality of connection pipes. The control valve for varying the pressure of the control valve is composed of a plurality of valve assemblies, one of which is installed inside the casing and the other is installed outside the casing, and the plurality of valve assemblies are connected by a connection pipe.

FIG. 12 is a perspective view explaining another embodiment of the capacity variable device according to the present invention, and FIGS. 13A and 13B are enlarged longitudinal sectional views showing embodiments of the first valve assembly in the capacity variable device according to FIG. And FIGS. 14A and 14B are schematic views showing the operation of the first valve assembly and the second valve assembly according to the operation mode of the compressor in FIG. 12, wherein FIG. 14A is a power mode and FIG. 14B is a saving mode .

As shown in the figure, the bottom surface of the back pressure plate 261 corresponding to the back surface of the second longitudinal plate 251 of the second scroll 250 is provided with a plurality of valve receiving grooves 261a are formed, and the plurality of valve receiving grooves 261a can communicate with each other by the communication grooves 261b.

One of the valve accommodating grooves or the communication groove 261b out of the plurality of valve accommodating grooves 261a is connected to one end of a discharge hole 261c for guiding the refrigerant bypassed into the suction space 211 of the casing 210 Respectively. The other end of the discharge hole 261c is formed to pass through the outer peripheral surface of the back pressure plate 261. Thus, the valve receiving groove 261a, the communication groove 261b, and the discharge hole 261c form an intermediate pressure chamber in which the intermediate pressure refrigerant is received when the check valve 255 is opened.

As shown in Figs. 12 to 13B, the outer peripheral surface of the back pressure plate 261 is provided so as to communicate with the end of the discharge hole 261c, and the discharge hole 261c is selectively opened and closed according to the operation mode of the compressor 1 valve assembly 270 is installed.

The first valve assembly 270 is a kind of check valve that opens and closes the discharge hole 261c while the piston valve 272 to be described later moves in accordance with the pressure difference between both sides. A piston 272 for opening and closing the discharge hole 261c is slidly inserted into the valve guide 271 while reciprocating in accordance with the pressure difference in the valve space 275. The piston 272 is opened and closed.

The valve guide 271 has a valve space 275 radially formed therein and an outer side of the valve space 275 is provided with a working pressure 272 on the rear surface of the piston valve 272 inserted into the valve space 275. [ A differential pressure space 276 for providing a differential pressure is provided.

The upper and lower sides of the valve space 275 are communicated with the discharge hole 261c to discharge the refrigerant discharged through the discharge hole 261c to the casing 210 as the suction space 211 when the piston valve 272 is pushed rearward An exhaust hole 275a is formed for guiding the exhaust gas to the internal space of the exhaust gas recirculation system.

An injection hole 276a is formed in one side of the differential pressure space 276 and a third connection pipe 283c to be described later is connected to the differential pressure space 276 in the injection hole 276a. The ends are joined. Thereby, the intermediate pressure or suction pressure refrigerant guided to the third connection pipe 283c is selectively supplied to the differential pressure space 276 through the injection hole 276a.

13A, the radial cross-sectional area A1 of the differential pressure space 276 is formed to be smaller than the radial cross-sectional area A2 of the valve space, and between the differential pressure space 276 and the valve space 275, a piston valve 272 And a stepped surface 276b for limiting the amount of thrusting of the piston valve 272 is formed. The injection hole 276a is formed in the differential pressure space 276 side relative to the step difference surface 276b between the valve space 275 and the differential pressure space 276. [

The sectional area A1 of the differential pressure space 276 is formed to be larger than the radial cross section A3 of the discharge hole 261c. Thus, even if the pressure in the discharge hole 261c and the pressure in the differential pressure space 276 are the same when the piston valve 272 is closed, the area applied to the rear face (back pressure face) of the piston valve 272 in the differential pressure space 276 Is larger than the area applied to the front face (open / close face) of the piston valve 272 in the discharge hole 261c, so that the piston valve 272 can maintain the closed state.

The piston valve 272 is formed in a circular cross-sectional shape having an outer diameter substantially equal to the inner diameter of the valve space 275 so as to be slidable in the valve space 275. The piston 272 moves in accordance with the difference between the pressure in the differential pressure space 276 and the pressure in the discharge hole 261c so that the opening face 272a and the back pressure surface 272b of the piston valve 272 are moved by the back pressure plate 272, The outer surface of the valve body 261 or the stepped surface of the valve guide 271. Accordingly, the piston valve 272 may be formed of a material such as an engineer plastic, which is capable of minimizing noise during impact and having a rigidity such that it is not damaged by collision, and that can smoothly slide have.

The piston valve 272 may be configured to move only by the pressure difference between the opening / closing surface 272a and the back pressure surface 272b as shown in FIG. 13A. However, in some cases, the piston valve 272 may be moved to the back pressure surface 272b A pressing spring 273 such as a compression coil spring may be further provided. In the case where the pressure spring 273 is provided, when the intermediate pressure does not reach a sufficient pressure as when the compressor is started and the pressure applied to the negative pressure surface is low, the piston valve 272 is pushed forward, 272 can be suppressed by the low pressure difference on both sides.

It is also possible to provide an O-ring groove (not designated) on the sliding surface of the valve guide 271 in contact with the outer diameter surface of the piston valve 272 and insert an O-ring 277 into the O-ring groove. Thus, leakage due to the differential pressure between the valve space 275 and the exhaust hole 275a can be prevented, and vibration due to the pressure difference of the piston valve 272 can be prevented.

12 to 13B, in the variable capacity scroll compressor according to the present embodiment, a second valve assembly 280 for operating the first valve assembly 270 is provided outside the casing. Accordingly, the second valve assembly 280 selectively provides intermediate or suction pressure to the first valve assembly 270 such that the first valve assembly 270 is pushed into the second valve assembly 270, It is operated by the difference of pressure.

Here, the second valve assembly 280 is composed of a solenoid valve which is an electromagnetic valve, which is similar to the above-described embodiment, and thus a detailed description thereof will be omitted.

Also in this embodiment, one end of the first connection pipe 283a may be connected to the intermediate pressure hole 268 of the back pressure plate 261 and the other end may be connected to the second valve assembly 280 through the casing 210 . Therefore, in the first connection pipe 283a of the present embodiment, like the first connection pipe 283a or the third connection pipe 283c of the above-described embodiment, also taking into account the vertical movement of the back pressure plate 261, And a second tube portion made of a flexible nylon injection tube.

The other end of the second tube portion is inserted into the intermediate pressure hole 268 with a third tube portion made of a metal insertion tube as in the above embodiment and is fastened by a U- .

Also in this case, the intermediate pressure hole 268 may be provided with a filter 290 for preventing foreign matter remaining in the back pressure chamber 260a from entering the intermediate pressure hole 268. [ The filter 290 may be formed in a disc shape having a plurality of fine holes and inserted in the middle of the intermediate pressure hole 268, or may be configured as in the embodiments shown in Figs. 7 to 10. The description thereof is the same as that of the above-described embodiment, and a description thereof will be omitted.

Reference numerals 258 and 259 denote gaskets and fixing pin insertion grooves, respectively.

The scroll compressor according to this embodiment operates as follows.

That is, as shown in FIG. 14A, during power operation, power is applied to the power supply unit 281 of the second valve assembly 280, and the mover 281b is pulled toward the coil 281a.

Then, the switching valve 286 coupled to the mover 281b is moved to the coil side (right side in the figure) 281a, and the first inlet / outlet 285a and the third inlet / outlet 285c of the valve housing 285 Communicate.

The intermediate pressure refrigerant in the back pressure chamber 260a moves to the valve housing 285 through the first connection pipe 283a connected to the first inlet 285a and the third connection pipe 285c connected to the third inlet 285c, (276) of the first valve assembly (270) through the first valve assembly (283c).

Then, the pressure in the differential pressure space 276 forms an intermediate pressure, and the piston valve 272 of the first valve assembly is pushed toward the discharge hole 261c to block the discharge hole 261c. At this time, the front side of the piston valve 272, that is, the opening / closing surface 272a is also brought into contact with the discharge hole 261c which forms the intermediate pressure, but the sectional area A3 of the discharge hole 261c is smaller than the sectional area The piston valve 272 moves in the direction of the discharge hole and blocks the discharge hole 261c.

Even if some refrigerant in the intermediate compartment of the compression chamber P opens the check valve 255 and discharges the refrigerant into the valve accommodating groove 261a through the bypass hole 251b, The communication groove 261b, and the discharge hole 261c. Then, no more refrigerant flows out from the compression chamber (P), and the compressor continues power operation.

On the other hand, as shown in FIG. 14B, during the saving operation, the power supply to the power supply unit 281 of the second valve assembly 280 is cut off and the mover 281b is pushed to the opposite side of the coil 281a by the return spring 281c.

Then, the switching valve 286 coupled to the mover 281b moves to the opposite side (the left side in the drawing) of the coil 281a to the second inlet / outlet 285b and the third inlet / outlet 285c of the valve housing 285, .

The suction pressure refrigerant is moved to the valve housing 285 while communicating with the suction space 211 of the casing 210 through the second connection pipe 283b connected to the second inlet 285b and the third inlet 285c To the differential pressure space 276 of the first valve assembly 270 through the third connection pipe 283c connected to the first valve assembly 270.

The pressure in the differential pressure space 276 forms the suction pressure so that the piston valve 272 of the first valve assembly 270 is moved toward the differential pressure space 276 by the pressure of the discharge hole 261c forming the intermediate pressure The discharge hole 261c is opened.

Then, the refrigerant, which has already been filled in the valve receiving groove 261a and the communication groove 261b and the discharge hole 261c through the check valve 255, quickly flows into the valve space 275 of the first valve assembly 270 And the refrigerant is discharged to the suction space 211 of the casing 210 through the discharge hole 275a formed in the valve space 275. [ Then, some refrigerant in the intermediate compartment refrigerant in the compression chamber (P) continues to be discharged along the above path, and the compressor continues the saving operation.

The scroll compressor according to this embodiment has a similar basic action and effect in that the second valve assembly corresponding to the control valve is installed outside the casing as in the above-described embodiment. In this embodiment, since the first valve assembly is installed at the end of the discharge passage for the refrigerant, when the refrigerant is switched from the power operation to the saving operation, the refrigerant has already reached the outlet end of the passage and is in a standby state. It can be quickly switched to driving.

On the other hand, in the above-described embodiments, the intermediate pressure holes are formed in the back pressure plate to guide the intermediate-pressure refrigerant in the back pressure chamber to the differential pressure space, or to be formed in the second scroll as the non- A part of the refrigerant may be introduced into the differential pressure space. In this case, the behavior of the first valve can be stabilized by operating the first valve assembly using the refrigerant of the compression chamber relatively small in pressure variation. Here, since the specific configuration and operation of the intermediate pressure hole are very similar to those of the above-described embodiment, a detailed description thereof will be replaced with the above-described embodiment.

In the above-described embodiments, the low-pressure scroll compressor is taken as an example. However, the present invention can be equally applied to a hermetic compressor in which the inner space of the casing is divided into a suction space of a low pressure portion and a discharge space of a high pressure portion.

Claims (8)

Casing;
A orbiting scroll provided in an inner space of the casing and performing a turning motion;
A non-orbiting scroll in which at least one or more bypass holes are formed so as to form a compression chamber formed of a suction chamber, an intermediate pressure chamber, and a discharge chamber in engagement with the orbiting scroll and to bypass a portion of the refrigerant in the intermediate pressure chamber to the inner space of the casing;
A back pressure chamber assembly provided on a back surface of the non-orbiting scroll to form a back pressure chamber so as to press the non-orbiting scroll in the orbiting scroll direction;
A first valve selectively opening and closing a flow path between the bypass hole and the internal space of the casing; And
And a second valve provided outside the casing and varying a pressure applied to a back pressure surface opposite to the bypass hole from both side surfaces of the first valve,
Wherein the back pressure chamber assembly or the non-orbiting scroll is provided with an intermediate pressure hole penetrating from the back pressure chamber to the outer peripheral surface thereof,
And a filter is provided in the intermediate pressure hole. The method according to claim 1,
The intermediate-
A first portion communicating with the back pressure chamber or the intermediate pressure chamber; And
And a second portion communicating with the outer peripheral surface of the back pressure chamber assembly or the intermediate pressure chamber of the non-orbiting scroll in the first portion,
The axial direction of the first part and the axial direction of the second part are formed so as to intersect with each other,
And the filter is installed between the first portion and the second portion. 3. The method of claim 2,
Wherein the second portion is formed with a stepped surface, and the filter is supported on the stepped surface. The method according to claim 1,
And a connection pipe connecting the back pressure chamber or the intermediate pressure chamber to the second valve is inserted into the intermediate pressure hole,
Wherein one side of the filter is supported by the coupling pipe and installed in the intermediate pressure hole. 5. The method of claim 4,
Wherein the intermediate pressure hole is formed with a stepped surface, and the filter is disposed between the stepped surface and the end of the connecting pipe, and both side surfaces thereof are supported. 5. The method of claim 4,
And the filter is fixedly coupled to a front end surface of the connection pipe. The method according to claim 1,
Wherein a stepped groove larger than the intermediate pressure hole is formed on a bottom surface of the back pressure chamber, and the filter is inserted and engaged with the stepped groove. 8. The method of claim 7,
Wherein the filter comprises a fixing part formed in the annular shape and inserted in the stepped groove, a mesh part coupled to the fixing part to filter out foreign matter, and a support part extending from the fixing part and supporting the mesh part Scroll compressor.

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