JP2017172505A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor capable of constantly keeping an optimum back-pressure of a movable scroll regardless of an operating condition, in particular, a scroll compressor capable of automatically eliminating a state that the back-pressure of the movable scroll is insufficient.SOLUTION: A scroll compressor includes a high-pressure fluid supply flow channel bored on a discharge casing for supplying a high-pressure fluid on which a discharge pressure of a working fluid acts, from a discharge chamber to a back-pressure chamber (Pm), a high-pressure fluid flow channel (7d) bored on an intermediate casing for supplying the high-pressure fluid to the back-pressure chamber, an intermediate-pressure fluid flow channel (7m) bored on the intermediate casing and lowering a pressure of the high-pressure fluid to supply the same to the back-pressure chamber as an intermediate-pressure fluid, and a member (20) for switching circulation and blockage of the high-pressure fluid from the high-pressure fluid flow channel to the back-pressure chamber by being displaced according to axial displacement of a thrust plate (9) in accompany with axial displacement of the movable scroll (3).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a scroll compressor that includes a fixed scroll and a movable scroll and compresses a working fluid by changing the volume of a compression chamber formed between the two scrolls. The present invention relates to a scroll compressor having a structure.

  For example, a scroll compressor is known as a compressor suitable for use in compressing a refrigerant in an air conditioner.

  The scroll compressor includes a fixed scroll and a movable scroll as a compression mechanism. Each of the fixed scroll and the movable scroll is composed of a disc-shaped end plate and a spiral wrap integrally formed with the end plate, and is arranged opposite to each other in the axial direction with both the spiral wraps engaged. Has been. Both spiral wraps are in partial contact with each other in a state where the phases are shifted from each other by 180 degrees, thereby forming a compression chamber as a sealed space between the spiral wraps.

  The orbiting scroll is configured to revolve around the central axis of the fixed scroll in a state where rotation is prevented as the drive shaft rotates. As a result, the compression chamber formed between the spiral wraps moves from the outer end of the spiral wrap toward the center, and the volume gradually decreases. Thus, the working fluid (for example, refrigerant gas) taken into the compression chamber from the outer end of the spiral wrap is compressed.

  In the scroll compressor configured as described above, due to the difference between the pressure in the compression chamber and the pressure on the back side of the end plate of the movable scroll (back pressure), the moving scroll is pulled away from the fixed scroll. A load acts. For this reason, the scroll compressor is configured to press the movable scroll toward the fixed scroll by forming a back pressure chamber on the back side of the end plate of the movable scroll and introducing pressure fluid there. As a result, it is possible to maintain the state in which both the spiral wraps are in contact with the corresponding scroll end plates, and the scroll compressor is ensured to operate efficiently.

  In Patent Document 1, a back pressure chamber is formed on the back side of the end plate of the movable scroll, and the working fluid compressed to the discharge pressure in the compression chamber is introduced into the back pressure chamber through a hole penetrating the end plate of the movable scroll. And the scroll compressor comprised so that a movable scroll may be pressed toward a fixed scroll is disclosed.

Japanese Patent Laid-Open No. 9-310687

  By the way, the pressure in the compression chamber formed between the fixed scroll and the movable scroll varies depending on the operating condition of the scroll compressor. Therefore, as in Patent Document 1, in the configuration in which a pressure fluid having a constant pressure is always supplied to the back pressure chamber formed on the back side of the end plate, for example, when the pressure in the compression chamber is high, the back pressure of the movable scroll is high. Is relatively short, and the movable scroll is pulled away from the fixed scroll. Such a situation is not preferable because it creates a gap between the two spiral wraps and the corresponding scroll end plate, leading to leakage of the working fluid in the compression process and, consequently, the compression efficiency of the scroll compressor. .

  The present invention has been made in view of the above-described problems, and is a scroll compressor that can always maintain the back pressure of the movable scroll optimally regardless of the operating conditions, in particular, the state in which the back pressure of the movable scroll is insufficient. It is an object of the present invention to provide a scroll compressor that can automatically solve the problem.

  In order to solve the above problems, a scroll compressor according to the present invention is formed on the back side of a movable scroll, and generates a back pressure that presses and urges the movable scroll toward the fixed scroll. An intermediate casing that houses the movable scroll and surrounds the back pressure chamber, a discharge casing that is provided on the back side of the fixed scroll and forms a discharge chamber between the fixed scroll and the intermediate casing A high pressure fluid which is perforated in the discharge casing and from which the discharge pressure of the working fluid acts from the discharge chamber to the back pressure chamber. A high-pressure fluid supply passage for supplying the high-pressure fluid, a high-pressure fluid passage formed in the intermediate casing and supplying the high-pressure fluid to the back pressure chamber, An intermediate pressure fluid passage that is perforated in the intermediate casing and supplies the back pressure chamber as an intermediate pressure fluid by reducing the pressure of the high pressure fluid, and an axial direction of the thrust plate accompanying an axial displacement of the movable scroll And a member that switches between the flow and blockage of the high-pressure fluid from the high-pressure fluid flow path to the back pressure chamber by being displaced according to the displacement.

  Preferably, the intermediate casing includes a first end surface extending in a radial direction at a position farther from the movable scroll than the thrust receiving surface in the axial direction, and the high-pressure fluid flow path exits to the first end surface. The member has an opening, and the member is disposed between the thrust plate and the first end surface, and is configured to open and close the outlet opening by being rotationally displaced in accordance with an axial displacement of the thrust plate. The

  Preferably, the member includes an L-shaped plate including an opening / closing portion and a thrust receiving portion that are perpendicular to each other, and a compression spring, and the opening / closing portion abuts on the first end surface to open the outlet opening. In the closed state, the thrust receiving portion is disposed between the thrust plate and the first end surface in such a manner that the end portion of the thrust receiving portion is in contact with the thrust plate, and the compression spring includes the opening / closing portion and the thrust plate. The intermediate casing is radially adjacent to the first end surface and extending in the radial direction at a position farther from the movable scroll than the first end surface in the axial direction. The thrust receiving portion and the spring are positioned on the opposite side in the radial direction with reference to a corner portion formed between the first end surface and the second end surface.

  Preferably, the compression spring has a repulsive force larger than a force required as a product of the area of the outlet opening and the pressure of the high-pressure fluid.

  Preferably, the opening / closing portion has a concave portion having a diameter larger than the outer diameter of the compression spring or a convex portion having a diameter smaller than the inner diameter of the compression spring at a portion in contact with the compression spring. Yes.

  Preferably, the opening / closing part has a convex part loosely fitted in the outlet opening.

  Preferably, the intermediate casing has a recess extending in an axial direction from the thrust receiving surface, and the member is disposed in the recess and is displaced in the axial direction in accordance with an axial displacement of the thrust plate. Thus, the high-pressure fluid from the high-pressure fluid flow path to the back pressure chamber is switched between the flow and the block.

  Preferably, the high-pressure fluid flow path is open to the recess, and the member includes a cylindrical valve housing, a valve body, and a compression spring, and one end face of the valve housing is the thrust. It is disposed in the recess so as to be flush with the receiving surface, and surrounds an outlet channel extending from the end surface and an inlet chamber communicating with the outlet channel, and the inlet chamber is the outlet flow A valve seat is formed at a transition portion from the inlet chamber to the outlet flow path by being formed with a diameter larger than the passage, and the valve body is disposed in the inlet chamber and abuts on the valve seat And a shaft portion that is formed integrally with the ball and configured to reciprocate in the outlet channel in the axial direction. The compression spring is provided between the bottom portion of the recess and the ball. The shaft portion is configured such that the ball contacts the valve seat. When that projects from the end face.

  Preferably, the high-pressure fluid flow path intersects the concave portion, and the member includes a valve body configured to be capable of reciprocating in the concave portion in an axial direction, a bottom portion of the concave portion, and the valve body. The high pressure fluid from the high pressure fluid flow path to the back pressure chamber when the through hole provided in the valve body is located at the intersection of the recess with the high pressure fluid flow path. When the through hole provided in the valve body is located closer to the thrust receiving surface than the intersection of the recess with the high-pressure fluid flow path, the valve body protrudes from the thrust receiving surface.

  According to the present invention, even if the pressure in the compression chamber fluctuates due to fluctuations in the operating conditions of the scroll compressor and the back pressure of the movable scroll is relatively insufficient, the axial direction of the movable scroll accompanying this Due to the forward displacement, the member for switching the flow and blocking of the flow path for supplying the high pressure fluid to the back pressure chamber formed on the back side of the movable scroll is displaced, and as a result, the high pressure fluid is supplied to the back pressure chamber. Therefore, the lack of back pressure is automatically resolved. Therefore, the back pressure of the movable scroll can always be kept optimal regardless of the operating conditions of the scroll compressor.

It is sectional drawing which shows the whole structure of the scroll compressor of this invention. It is principal part sectional drawing in the circumferential direction position different from FIG. 1 of the scroll compressor which concerns on the 1st aspect of this invention. It is a perspective view which shows the shape of the pressure adjustment plate in the scroll compressor which concerns on the 1st aspect of this invention. It is a schematic explanatory drawing which shows the opening-and-closing state of the high pressure oil supply flow path outlet opening part by the pressure adjustment plate in the scroll compressor which concerns on the 1st aspect of this invention. It is principal part sectional drawing in the circumferential direction position different from FIG. 1 of the scroll compressor which concerns on the 2nd aspect of this invention. It is a schematic explanatory drawing which shows the distribution | circulation / interruption | blocking state of the high pressure oil supply flow path by a ball valve in the scroll compressor which concerns on the 2nd aspect of this invention. It is principal part sectional drawing in the circumferential direction position different from FIG. 1 of the scroll compressor which concerns on the 3rd aspect of this invention. It is principal part sectional drawing which shows the 1st addition aspect regarding the intermediate pressure oil discharge flow path in the scroll compressor of this invention. It is principal part sectional drawing which shows the 2nd addition aspect regarding the intermediate pressure oil discharge flow path in the scroll compressor of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The overall structure of the scroll compressor of the present invention will be described with reference to FIG. In the following description, the suction side and the discharge side (left side and right side in FIG. 1, respectively) of the scroll compressor are defined as the front side and the rear side of the scroll compressor, respectively.

  The scroll compressor 1 has a structure in which a fixed scroll 2, a movable scroll 3, a shaft 4, and an electric motor 5 as main components are housed in a cylindrical casing.

  The fixed scroll 2 and the movable scroll 3 constituting the compression mechanism of the scroll compressor 1 are arranged to face each other in the axial direction of the scroll compressor 1 (the direction of the central axis CL).

  The fixed scroll 2 includes a disc-shaped end plate 2a and a spiral wrap 2b integrally formed with the end plate 2a. Similarly, the movable scroll 3 includes a disc-shaped end plate 3a and an end plate 2a. It is comprised from the spiral wrap 3b integrally formed in the board 3a.

  The two scrolls 2 and 3 are engaged with the spiral wraps 2b and 3b, the tip end in the axial direction of the spiral wrap 2b of the fixed scroll 2 contacts the end plate 3a of the movable scroll 3, and the spiral wrap of the movable scroll 3 The tip end portions in the axial direction of 3b are arranged so as to contact the end plate 2a of the fixed scroll 2, respectively. Note that a tip seal is embedded at the axial tip portions of the spiral wraps 2b and 3b (in FIG. 1, only the tip seal 2c embedded at the axial tip portion of the spiral wrap 2b is shown). .

  The scrolls 2 and 3 are arranged such that the side surfaces of the spiral wraps 2b and 3b are partially in contact with each other in a state where the phases of the spiral wraps 2b and 3b are shifted from each other by 180 degrees. Thereby, the compression chamber C which is sealed space is formed between both the spiral wraps 2b and 3b.

  As will be described later, the movable scroll 3 is connected to the shaft 4 at a cylindrical boss 3c provided on the back surface of the end plate 3a (the surface opposite to the surface on which the spiral wrap 3b is formed) Due to the action of the shaft 4 and a rotation prevention mechanism (not shown), a revolving and swiveling motion is performed around the central axis CL while the rotation is prevented. As a result, the compression chamber C formed between the spiral wraps 2b and 3b moves from the outer end of the spiral wraps 2b and 3b toward the center, and the volume gradually decreases. As a result, the working fluid (for example, refrigerant gas) taken into the compression chamber C from the outer ends of the spiral wraps 2b and 3b is compressed.

  A discharge hole 2d penetrating through the end plate 2a is provided at a central portion in the radial direction of the end plate 2a of the fixed scroll 2. The working fluid compressed in the compression chamber C is discharged to the back surface (surface opposite to the surface on which the spiral wrap 2b is formed) side of the end plate 2a of the fixed scroll 2 through the discharge hole 2d. A one-way valve 2e such as a reed valve is provided at the outlet of the discharge hole 2d to prevent the working fluid from flowing back into the compression chamber C.

  The casing of the scroll compressor 1 includes a front casing 6, a center casing 7, and a rear casing 8.

  The front casing 6 and the center casing 7, and the center casing 7 and the rear casing 8 are fastened by fasteners (bolts, nuts, etc.) not shown on the axial end surfaces of the respective casings.

  The front casing 6 includes an end wall portion 6a formed in a substantially disc shape, a substantially cylindrical outer shell portion 6b extending rearward in the axial direction from an outer peripheral edge portion of the end wall portion 6a, and a radial direction of the end wall portion 6a. It is comprised from the cylindrical bearing support part 6c provided in the center part vicinity. Thus, a suction chamber S having a front end closed by the end wall portion 6a and a rear end opened is formed inside the front casing 6.

  The center casing 7 (intermediate casing) has an outer shell portion 7a formed in a substantially cylindrical shape, and a substantially truncated cone shape that extends radially inward and axially forward from a substantially central portion in the axial direction of the outer shell portion 7a. Bearing support portion 7b. As a result, the center casing 7 houses the fixed scroll 2 and the movable scroll 3 inside the outer shell portion 7a behind the bearing support portion 7b. A rolling bearing 7c that rotatably supports the shaft 4 is fitted in the vicinity of the front end portion of the bearing support portion 7b.

  The rear casing 8 (discharge casing) is fastened to the center casing 7 with the outer peripheral edge of the end plate 2 a of the fixed scroll 2 sandwiched between the rear casing 8 and the discharge casing. A concave portion is formed in the central portion in the radial direction of the rear casing 8, thereby forming a discharge chamber 8 a between the end plate 2 a of the fixed scroll 2.

  The shaft 4 is rotationally driven by the electric motor 5 and thereby has a function of causing the orbiting scroll 3 to revolve around the central axis CL.

  The shaft 4 includes a shaft body 4a and an eccentric pin portion 4c that protrudes from the rear end surface 4b of the shaft body 4a to the movable scroll 3 side.

  The shaft main body 4a is rotatably supported at its front end portion by a slide bearing 6d fitted to the inner periphery of the bearing support portion 6c of the front casing 6, and in the vicinity of the rear end surface 4b, the bearing of the center casing 7 is supported. It is rotatably supported by a rolling bearing 7c fitted to the inner periphery of the support portion 7b.

  An eccentric bush 4d is fitted and fixed to the outer periphery of the eccentric pin portion 4c. On the other hand, a sliding bearing 3e is fitted and fixed to the inner periphery of a cylindrical boss 3c provided on the back surface of the movable scroll 3. The shaft 4 and the movable scroll 3 are slidably connected to each other by fitting the eccentric bush 4d to the inner periphery of the slide bearing 3e.

  A counterweight 4e is fitted and fixed at a portion between the rear end surface 4b of the shaft body 4a and the rolling bearing 7c. The center of gravity of the counterweight 4e is at a position that is 180 degrees out of phase with the eccentric pin portion 4c. As a result, the unbalanced load generated by the orbiting scroll 3 revolving around the rotation of the shaft 4, that is, by swinging around the central axis CL is offset, and excessive vibration is generated in the shaft 4. To prevent it.

  The suction chamber S formed inside the front casing 6 accommodates an electric motor 5 for driving the shaft 4 to rotate.

  The electric motor 5 includes a stator 5a and a rotor 5b. The stator 5 a is formed in a cylindrical shape, and is fitted into the inner periphery of the outer shell portion 6 b of the front casing 6. The rotor 5 b is also formed in a cylindrical shape, and is fitted on the outer periphery of the shaft 4. The stator 5a and the rotor 5b are coaxially arranged with a minute radial gap between them, and by supplying current from the outside to a coil (not shown) provided in the stator 5a, the rotor 5b Rotate.

  A suction hole (not shown) is provided in the vicinity of the opened rear end portion of the outer shell portion 6b of the front casing 6, and the working fluid supplied through the suction port 6s passes through the suction hole to the inside of the front casing 6. Is sucked into the suction chamber S. The sucked working fluid flows into the center casing 7 through the open rear end portion of the outer shell portion 6b, passes through the fluid circulation holes (not shown) provided in the bearing support portion 7b, and the two spiral wraps 2b, It is introduced into the suction chamber 7s at the outer end of 3b, taken into the compression chamber C from the outer end side of the spiral wraps 2b and 3b, and compressed. The compressed working fluid is discharged to the discharge chamber 8a through the discharge hole 2d provided in the center portion in the radial direction of the end plate 2a of the fixed scroll 2, and is led out to the outside through a discharge port (not shown). .

  In the scroll compressor 1 configured as described above, due to the difference between the pressure in the compression chamber C and the pressure (back pressure) on the back side of the end plate 3a of the movable scroll 3, the movable scroll 3 is A load acting in a direction away from the fixed scroll 2 (leftward in FIG. 1) acts. Therefore, the scroll compressor 1 maintains the state in which the spiral wraps 2b and 3b are in contact with the corresponding scroll end plates 3a and 2b in order to ensure high-efficiency operation. A back pressure chamber is formed on the back side, and pressure fluid is introduced into the back pressure chamber, thereby pressing the movable scroll 3 toward the fixed scroll 2. This configuration will be described in detail below.

  A thrust receiving surface 7e extending in the radial direction is formed on the movable scroll 3 side of the bearing support portion 7b of the center casing 7, and between the thrust receiving surface 7e and the end plate 3a of the movable scroll 3, An annular thrust plate 9 is provided. Between the outer peripheral part of the thrust plate 9, the outer peripheral part of the bearing support part 7b, and the outer peripheral part of the end plate 3a of the movable scroll 3, annular seal members 7f and 3d are interposed, respectively.

  The space surrounded by the bearing support portion 7b of the center casing 7, the shaft 4, the end plate 3a of the movable scroll 3 and the thrust plate 9 is configured to be supplied with medium-pressure lubricating oil, as will be described later. In this specification, this space is referred to as an intermediate pressure chamber Pm.

  The thrust plate 9 has a function of pressing the movable scroll 3 backward, that is, toward the fixed scroll 2 by the action of the pressure of the lubricating oil supplied to the intermediate pressure chamber Pm. Therefore, although the thrust plate 9 is depicted in FIG. 1 as being in contact with the thrust receiving surface 7e, the thrust plate 9 is slightly lifted from the thrust receiving surface 7e in a state where a thrust load is applied backward due to the pressure of the lubricating oil. There is also a space. This space is also a part of the intermediate pressure chamber Pm, and its outer peripheral edge is the position of the seal member 7f.

  In the intermediate pressure chamber Pm, as shown in FIG. 1, an intermediate pressure oil supply passage 7m (intermediate pressure fluid passage) is opened at one place in the lower part in the vertical direction. The lubricating oil introduced into the intermediate pressure chamber Pm through the intermediate pressure oil supply channel 7m applies a thrust load to the thrust plate 9 and the end plate 3a of the movable scroll 3.

  Further, as shown in FIGS. 2, 5, and 7, the intermediate pressure chamber Pm has a high pressure oil via a switching member described later at a circumferential position that is different from the intermediate pressure oil supply flow path 7m at the lower part in the vertical direction. It communicates with the supply channel 7d (high pressure fluid channel).

  The high-pressure oil supply flow path 7d and the intermediate-pressure oil supply flow path 7m are drilled inside the outer shell portion 7a and the bearing support portion 7b of the center casing 7 in the lower part in the vertical direction.

  Both flow paths are preferably drilled at different positions in the circumferential direction for the convenience of installing a switching member, which will be described later, inside the bearing support portion 7b, but may be drilled without crossing each other. For example, both flow paths may be provided at the same circumferential position.

  Each of the flow paths has an inlet opening at the joint end surface of the center casing 7 with the rear casing 8, and from there, an axial flow path portion extending axially forward in the outer shell portion 7a, and an axial direction And a radial flow path portion extending radially inward from the front end of the flow path portion in the bearing support portion 7b. All the flow paths communicate with the intermediate pressure chamber Pm at the end of the radial flow path portion. Further, an orifice 7n for reducing the pressure of the high-pressure oil supplied to the inlet opening to an intermediate pressure is embedded in the axial flow path portion of the intermediate pressure oil supply path 7m.

  An oil separation wall 8 b is provided at the lower portion of the rear casing 8 in the vertical direction. On the other hand, an oil separation wall 2f is also provided on the back side of the end plate 2a of the fixed scroll 2 at a portion substantially facing the oil separation wall 8b in the axial direction. Both oil separation walls 8b and 2f cooperate to form an oil storage chamber 8c.

  The working fluid discharged from the discharge hole 2 d provided in the end plate 2 a of the fixed scroll 2 to the discharge chamber 8 a contains lubricating oil for lubricating the bearing of the scroll compressor 1. This lubricating oil collides with the inner wall of the discharge chamber 8a and the oil separation walls 8b and 2f, and is separated from the working fluid by adhering to these walls. The separated lubricating oil flows down to the oil storage chamber 8c by the action of gravity and is stored therein.

  A total of two high pressure oil supply flow paths 8d shown in FIG. 1 and high pressure oil supply flow paths 8d shown in FIG. 2, FIG. 5, and FIG. The high-pressure oil supply channel 8d (high-pressure fluid supply channel) is open. The two high-pressure oil supply flow paths 8d extend to the joint end surface of the rear casing 8 with the center casing 7, respectively, where the high-pressure oil supply flow having an inlet opening at the joint end surface of the center casing 7 with the rear casing 8 is provided. It communicates with the passage 7d and the medium pressure oil supply passage 7m.

  The shaft body 4a has a first oil passage 4h drilled from the rear end face 4b in the axial direction forward and a second oil passage 4j drilled from the front end face in the axial rearward direction. Is provided. Since the eccentric pin portion 4c protrudes from the rear end surface 4b of the shaft body 4a, the first oil passage 4h extends not at the center axis CL but at a position eccentric from the center axis CL. On the other hand, the second oil passage 4j extends on the central axis CL. Both flow paths communicate with each other at the front end portion, and as a whole, an oil flow path is formed from the rear end face 4b of the shaft body 4a to the front end face. An orifice 4k is embedded at the front end of the second oil passage 4j so that the pressure on the upstream side is maintained at a pressure equivalent to that of the intermediate pressure chamber Pm.

  Further, a seal ring 4f is fitted at a position in front of the rolling bearing 7c in the shaft body 4a, and an annular seal member 4g is fitted in a groove provided on the outer peripheral surface thereof. The seal member 4g is in sliding contact with the inner peripheral surface of the bearing support portion 7b of the center casing 7, and thereby seals between the intermediate pressure chamber Pm and the suction chamber S.

  The lubricating oil separated from the working fluid in the discharge chamber 8 a in the rear casing 8 and stored in the oil storage chamber 8 c is a high-pressure oil having a high pressure corresponding to the discharge pressure of the scroll compressor 1. This high-pressure oil is introduced into a high-pressure oil supply flow path 8 d formed in the rear casing 8, and reaches the joint end surface between the rear casing 8 and the center casing 7. From there, the high-pressure oil that has flowed into the medium-pressure oil supply flow path 7m drops to a medium pressure at the orifice 7n and flows into the medium-pressure chamber Pm. On the other hand, the high-pressure oil that has flowed into the high-pressure oil supply flow path 7d reaches a switching member that will be described later.

  The lubricating oil that has flowed into the intermediate pressure chamber Pm is used for lubrication of the rolling bearing 7c and the sliding bearing 3e. The lubricating oil in the intermediate pressure chamber Pm then flows into the first oil passage 4h provided in the shaft body 4a of the shaft 4, and further passes through the second oil passage 4j and the orifice 4k embedded in the downstream end thereof. Then, it flows into the oil discharge chamber 6e. From here, the lubricating oil flows into the suction chamber S while lubricating the slide bearing 6d, and passes through the space around the stator 5a and the rotor 5b of the electric motor 5 to reach the rear of the suction chamber S. Therefore, the working fluid supplied into the suction chamber S through the suction port 6s is merged and introduced again into the suction chamber 7s at the outer ends of the spiral wraps 2b and 3b. Note that the lubricating oil path from the intermediate pressure chamber Pm to the suction chamber S does not pass through the shaft 4 by using, for example, a through hole provided in the bearing support portion 7b of the center casing 7. It may be configured.

  In this way, the lubricating oil circulates inside the scroll compressor 1.

  In the above description, the lubricating oil separated from the working fluid in the discharge chamber 8a in the rear casing 8 has been described as being supplied to the intermediate pressure chamber Pm, but from the discharge chamber 8a in the rear casing 8 Even when the working fluid is supplied to the intermediate pressure chamber Pm, the back pressure control can be performed similarly.

  The scroll compressor according to the present invention is configured such that when the back pressure of the movable scroll (pressure in the intermediate pressure chamber) is insufficient, the high pressure oil is automatically introduced into the intermediate pressure chamber, and the back pressure shortage is resolved. Has been.

  Specifically, in the state where the back pressure is insufficient, the movable scroll 3 is displaced toward the intermediate pressure chamber Pm, in other words, toward the bearing support portion 7b of the center housing 7, and this displacement is used. Accordingly, a member for switching supply / interruption of high pressure oil to / from the intermediate pressure chamber Pm is provided.

  This configuration will be described in detail below.

<First aspect>
A first aspect of the present invention will be described with reference to FIG.

  FIG. 2 is a cross-sectional view of the main part of the scroll compressor according to the first aspect at a circumferential position different from that in FIG. 1.

  In the first aspect, a member that opens and closes the outlet opening to the medium pressure chamber Pm of the high-pressure oil supply flow path 7d by rotating according to the axial displacement of the movable scroll 3 is provided as the switching member.

  In order to secure a space for arranging the opening / closing member, the thrust receiving surface 7e is notched forward in the axial direction in the radially inner region. The cutout is preferably provided over the entire circumference so that the processing can be easily performed, but may be local in the circumferential direction as long as the opening / closing member can be accommodated.

  A first end surface 7p and a second end surface 7q extending in the radial direction are formed in the bearing support portion 7b of the center housing 7 by the notches. The second end surface 7q is adjacent to the first end surface 7p in the radial direction and is positioned forward in the axial direction. As a result, a step is formed between the first end surface 7p and the second end surface 7q. ing. In addition, although the example which has arrange | positioned the 2nd end surface 7q in the radial inside of the 1st end surface 7p is shown in FIG. 2, you may arrange | position the 2nd end surface 7q in the radial direction outer side of the 1st end surface 7p.

  In one embodiment, the switching member can be configured as an L-shaped pressure adjustment plate 20.

  As shown in FIG. 2, the pressure adjusting plate 20 is oriented so that the opening / closing portion 21 forming one side of the L-shape is oriented in the radial direction and the thrust receiving portion 22 forming the other side of the L-shape is oriented in the axial direction. As described above, the thrust plate 9 is disposed between the first end surface 7p and the second end surface 7q. The pressure adjusting plate 20 is configured such that the end of the thrust receiving portion 22 is in a state where the opening / closing portion 21 abuts on the first end surface 7p and closes the outlet opening to the medium pressure chamber Pm of the high pressure oil supply passage 7d. In this state, the thrust plate 9 and the thrust receiving surface 7e are spaced apart from each other in the axial direction, as shown in FIG.

  The opening / closing part 21 has a first surface 21a on the side where the thrust receiving part 22 extends, and a second surface 21b on the back side of the first surface 21a. A compression spring 23 is interposed between the first surface 21 a of the opening / closing part 21 and the thrust plate 9. The compression spring 23 has a function of urging the opening / closing part 21 in a direction away from the thrust plate 9. The thrust receiving portion 22 and the compression spring 23 are located on the opposite side in the radial direction with respect to the corner portion 7r formed between the first end surface 7p and the second end surface 7q.

  One end of the compression spring 23 is fixed to the thrust plate 9 by an appropriate method. The other end of the compression spring 23 is fitted in a spring guide formed on the first surface 21 a of the opening / closing part 21.

  As shown in FIG. 3A, the spring guide can be configured as a recess 21 c formed on the first surface 21 a of the opening / closing part 21 and having an inner diameter larger than the outer diameter of the compression spring 23. Instead of this, the spring guide is formed as a convex portion 21d formed on the first surface 21a of the opening / closing portion 21 and having an outer diameter smaller than the inner diameter of the compression spring 23, as shown in FIG. Also good.

  Further, as shown in FIG. 3B, a convex portion 21e having a diameter sufficiently smaller than the diameter of the outlet opening of the high-pressure oil supply channel 7d is formed on the second surface 21b of the opening / closing portion 21, and the convex portion The part 21e may be configured to be fitted into the outlet opening of the high-pressure oil supply channel 7d. The convex portion 21e loosely fitted in the outlet opening of the high-pressure oil supply flow path 7d secures a space for the high-pressure oil to circulate on the outer periphery, while the pressure adjustment plate 20 is displaced from the outlet opening of the high-pressure oil supply flow path 7d. It functions so as to avoid a situation where it cannot function as a switching member.

  The operation of the pressure adjustment plate 20 configured as described above will be described with reference to FIG.

  When the back pressure of the movable scroll 3 is in an appropriate state, as shown in FIG. 4A, the opening / closing portion 21 of the pressure adjusting plate 20 is pressed against the first end surface 7p of the bearing support portion 7b by the compression spring 23. ing.

  The compression spring 23 is configured to have a repulsive force larger than a force required as a product of the area of the outlet opening of the high-pressure oil supply channel 7d and the pressure of the high-pressure oil. As a result, the compression spring 23 overcomes the force by which the high pressure oil attempts to float the opening / closing portion 21 of the pressure adjusting plate 20 from the first end surface 7p of the bearing support portion 7b, and the opening / closing portion 21 of the pressure adjusting plate 20 The state of being in contact with the first end face 7p of the support portion 7b can be maintained.

  In this state, the outlet opening of the high-pressure oil supply channel 7d is closed by the opening / closing part 21 of the pressure adjustment plate 20, and the high-pressure oil does not flow into the intermediate pressure chamber Pm.

  Next, when the back pressure of the movable scroll 3 is insufficient, as shown in FIG. 4B, the movable scroll 3 moves toward the intermediate pressure chamber Pm, in other words, the bearing support portion 7b of the center housing 7. Displace towards. Then, the thrust receiving portion 22 of the pressure adjustment plate 20 is pressed toward the bearing support portion 7b of the center housing 7 by the thrust plate 9, and the pressure adjustment plate 20 is connected to the first end surface 7p and the second end surface of the bearing support portion 7b. In this example, it rotates counterclockwise around the corner 7r between 7q. As a result, the opening / closing portion 21 of the pressure adjusting plate 20 is slightly inclined from the radial direction, and the portion of the opening / closing portion 21 opposite to the thrust receiving portion 22 floats from the first end surface 7p of the bearing support portion 7b. As a result, the state where the opening / closing part 21 of the pressure adjusting plate 20 is in contact with the first end face 7p of the bearing support part 7b is released, and the outlet opening of the high-pressure oil supply flow path 7d is opened. Thereby, the high pressure oil is supplied to the intermediate pressure chamber Pm, the pressure in the intermediate pressure chamber Pm is increased, and the back pressure shortage is resolved. When the pressure in the intermediate pressure chamber Pm has recovered to an appropriate back pressure, as described above, the outlet opening of the high pressure oil supply channel 7d is closed again, so that the pressure in the intermediate pressure chamber Pm is appropriate. Excessive pressure will not be exceeded.

  As described above, according to the first aspect of the present invention, even when the back pressure of the movable scroll is insufficient, the pressure adjustment plate is inclined due to the displacement of the movable scroll in the axial direction along with the high pressure oil. Since the opening to the intermediate pressure chamber of the supply channel is opened, high pressure oil is supplied to the intermediate pressure chamber, and the back pressure shortage is automatically resolved.

  In the above description, the example in which the opening to the middle pressure chamber of the high-pressure oil supply flow path is opened and closed using the L-shaped pressure adjustment plate has been described. If it inclines in the aspect which the opening part to the intermediate pressure chamber of a high pressure oil supply flow path opens by the displacement to, it will not be limited to the thing of an above-described aspect.

<Second aspect>
A second aspect of the present invention will be described with reference to FIG.

  FIG. 5 is a cross-sectional view of a main part of the scroll compressor according to the second aspect at a circumferential position different from that in FIG. 1.

  In the second aspect, as the switching member, a member that switches between flow / blocking of the high-pressure oil supply flow path 7d by being displaced in the axial direction in accordance with the axial displacement of the movable scroll 3 is provided.

  In order to secure a space for arranging the switching member, the bearing support portion 7b is provided with a recess 7t from the thrust receiving surface 7e toward the front in the axial direction, and the bottom or side of the recess 7t has a high pressure. It communicates with the oil supply channel 7d.

  In one embodiment, the switching member can be configured as a ball valve 30.

  As shown in FIG. 5, the ball valve 30 includes a valve housing 31, a valve body 32, and a compression spring 33.

  The valve housing 31 is a substantially cylindrical member, and is disposed in the recess 7t so that one end surface thereof is flush with the thrust receiving surface 7e. The valve housing 31 surrounds an outlet channel 31b extending from the end surface and an inlet chamber 31a communicating with the outlet channel 31b. The inlet chamber 31a is formed to have a larger diameter than the outlet channel 31b, and thereby, a valve seat 31c with which a ball 32a of a valve body 32 (to be described later) abuts at a transition portion from the inlet chamber 31a to the outlet channel 31b. Is formed.

  The valve body 32 includes a ball 32a and a shaft portion 32b formed integrally with the ball 32a.

  The ball 32a is a spherical member, and is configured to be able to reciprocate in the longitudinal direction in the inlet chamber 31a and to contact the valve seat 31c. The shaft portion 32b is a cylindrical member, and is inserted into the outlet channel 31b described above. The outer diameter of the shaft part 32b is such that the shaft part 32b can reciprocate in the longitudinal direction in the outlet channel 31b, and a high-pressure oil channel can be formed around the shaft part 32b. It is configured sufficiently smaller than. Further, as will be described later, the length of the shaft portion 32b is such that the tip of the shaft portion 32b (the end opposite to the ball 32a) is axially moved by the thrust plate 9 when the back pressure of the movable scroll 3 is insufficient. The ball 32a of the valve body 32 is configured to be separated from the valve seat 31c by being pushed forward. In other words, the shaft portion 32b is configured to have such a length that the tip protrudes from the thrust receiving surface 7e when the ball 32a is in contact with the valve seat 31c.

  The compression spring 33 has a function of pressing the valve body 32 toward the movable scroll 3, and one end thereof is fixed to the ball 32 a and the other end is fixed to the bottom of the recess 7 t.

  The operation of the ball valve 30 configured as described above will be described with reference to FIG.

  When the back pressure of the movable scroll 3 is in an appropriate state, the ball 32a is in contact with the valve seat 31c and the ball valve 30 is closed as shown in FIG. 6 (A). In this state, the high pressure oil in the high pressure oil supply channel 7d is stored in the inlet chamber 31a and does not flow into the intermediate pressure chamber Pm.

  Next, when the back pressure of the movable scroll 3 is insufficient, as shown in FIG. 6B, the movable scroll 3 moves toward the intermediate pressure chamber Pm, in other words, the bearing support portion 7b of the center housing 7. Displace towards. Then, the shaft portion 32b of the valve body 32 is pushed forward in the axial direction by the thrust plate 9, and accordingly, the ball 32a of the valve body 32 is separated from the valve seat 31c. That is, the ball valve 30 is opened, and the high-pressure oil in the high-pressure oil supply passage 7d flows from the inlet chamber 31a through the outlet passage 31b into the intermediate pressure chamber Pm. As a result, the pressure in the intermediate pressure chamber Pm increases, and the back pressure shortage is resolved. Note that, when the pressure in the intermediate pressure chamber Pm is restored to an appropriate back pressure, the ball 32a comes into contact with the valve seat 31c and the ball valve 30 is closed as described above, so that the intermediate pressure chamber Pm The pressure does not exceed the appropriate back pressure and is not excessive.

  As described above, according to the second aspect of the present invention, even when the back pressure of the movable scroll is insufficient, the ball valve opens due to the displacement of the movable scroll in the axial direction and the high pressure oil is supplied. Since high pressure oil is supplied from the flow path to the intermediate pressure chamber, the back pressure shortage is automatically resolved.

<Third aspect>
A third aspect of the present invention will be described with reference to FIG.

  FIG. 7 is a cross-sectional view of the main part of the scroll compressor according to the third aspect at a circumferential position different from that in FIG. 1.

  In the third mode, as in the second mode, a member that switches the flow / blocking of the high-pressure oil supply channel 7d by displacing in the axial direction according to the axial direction displacement of the movable scroll 3 is provided as the switching member. ing.

  Therefore, also in the third mode, as in the second mode, in order to arrange the switching member, the bearing support portion 7b is provided with a recess 7t from the thrust receiving surface 7e toward the front in the axial direction. In the third aspect, the recess 7t is provided so as to intersect the high-pressure oil supply flow path 7d.

  In one embodiment, the switching member can be configured as a spool valve 40.

  As shown in FIG. 7, the spool valve 40 includes a valve body 41 and a compression spring 42.

  The valve body 41 is configured to be able to slide in the recess 7t, and a valve hole 41a which is a through hole is provided in a substantially central portion in the longitudinal direction. The position of the valve hole 41a in the longitudinal direction of the valve body 41 is such that the tip of the valve body 41 (the end opposite to the compression spring 42) is thrust when the back pressure of the movable scroll 3 is insufficient. The plate 9 is pushed forward in the axial direction, and the valve hole 41a is set to be in communication with the high-pressure oil supply flow path 7d.

  The compression spring 42 has a function of pressing the valve body 41 toward the movable scroll 3, one end of which is fixed to the valve body 41 and the other end is fixed to the bottom of the recess 7 t. Therefore, the tip of the valve body 41 is always in contact with the surface of the thrust plate 9 by the urging force of the compression spring 42.

  The operation of the spool valve 40 configured as described above will be described below.

  When the back pressure of the movable scroll 3 is in an appropriate state, the valve element 41 has a tip projecting axially rearward from the thrust receiving surface 7e, and the valve hole 41a is positioned axially rearward from the high-pressure oil supply flow path 7d. The two are not in communication. In this state, the high pressure oil in the high pressure oil supply flow path 7d is blocked by the valve body 41 and does not flow into the intermediate pressure chamber Pm.

  Next, when the back pressure of the movable scroll 3 is insufficient, the movable scroll 3 is displaced toward the intermediate pressure chamber Pm, in other words, toward the bearing support portion 7 b of the center housing 7. Then, the valve body 41 is pushed forward in the axial direction by the thrust plate 9, and the valve hole 41a is in communication with the high-pressure oil supply flow path 7d. That is, the spool valve 40 is opened, and the high-pressure oil in the high-pressure oil supply passage 7d passes through the valve hole 41a and flows into the intermediate pressure chamber Pm. As a result, the pressure in the intermediate pressure chamber Pm increases, and the back pressure shortage is resolved. When the pressure in the intermediate pressure chamber Pm has recovered to an appropriate back pressure, as described above, the communication state between the valve hole 41a and the high-pressure oil supply flow path 7d is canceled and the spool valve 40 is closed. Therefore, the pressure in the intermediate pressure chamber Pm does not exceed an appropriate back pressure and becomes an excessive pressure.

  The first to third aspects described above are configured such that high pressure oil is automatically supplied to the intermediate chamber when the back pressure of the movable scroll is insufficient. Although it is possible to eliminate the back pressure shortage of the movable scroll automatically only by these aspects, in order to further enhance the effect, when the back pressure of the movable scroll is insufficient, the low pressure portion from the intermediate chamber You may use together the additional aspect shown below comprised so that the oil discharge to may be combined with a 1st-3rd aspect.

<First addition mode>
In the first additional mode, as shown in FIG. 8, the intermediate pressure oil discharge passage 7 u is configured so as to penetrate the bearing support portion 7 b from the thrust receiving surface 7 e to the suction chamber S.

  When the back pressure of the movable scroll 3 is in an appropriate state, the thrust plate 9 is in a state of being separated from the thrust receiving surface 7e in the axial direction rearward, and the intermediate pressure oil discharge passage 7u opens to the intermediate pressure chamber Pm. In this state, the medium pressure oil in the medium pressure chamber Pm is discharged to the suction chamber S after dropping by a predetermined amount at the orifice 7v provided in the medium pressure oil discharge channel 7u. As a result, the medium pressure chamber Pm The internal pressure (back pressure) is properly maintained.

  Next, when the back pressure of the movable scroll 3 is insufficient, the movable scroll 3 is displaced toward the intermediate pressure chamber Pm, in other words, toward the bearing support portion 7 b of the center housing 7. Then, the thrust plate 9 comes into contact with the thrust receiving surface 7e, and the opening to the intermediate pressure chamber Pm of the intermediate pressure oil discharge passage 7u is closed. In this state, the medium pressure oil in the medium pressure chamber Pm is not discharged to the suction chamber S through the medium pressure oil discharge channel 7u, and as a result, the pressure (back pressure) in the medium pressure chamber Pm is It rises and eventually returns to the proper state. When the pressure in the intermediate pressure chamber Pm is restored to an appropriate back pressure, as described above, the thrust plate 9 is separated from the thrust receiving surface 7e in the axial direction rearward, and the intermediate pressure oil discharge passage 7u is at the intermediate pressure. Since it opens to the chamber Pm, the pressure of the intermediate pressure chamber Pm does not exceed an appropriate back pressure and becomes an excessive pressure.

  In FIG. 1, a first oil passage 4h and a second oil passage 4j are formed in the shaft body 4a of the shaft 4 to form an intermediate pressure oil discharge path from the intermediate pressure chamber Pm to the intake chamber S. However, this route is not necessarily provided in this additional mode. This is because, instead of the orifice 4k disposed at the downstream end of the second oil passage 4j, the orifice 7v provided in the intermediate pressure oil discharge passage 7u can perform the pressure adjusting function of the intermediate pressure chamber Pm.

  Further, when the medium pressure oil discharge path in the shaft 4 and the medium pressure oil discharge flow path 7u described above are used in combination, the medium pressure chamber by the orifice 4k arranged at the downstream end of the second oil flow path 4j. Since the pressure adjusting action of Pm can be used, installation of the orifice 7v in the intermediate pressure oil discharge flow path 7u can be omitted. However, in this case, in order to prevent the pressure in the intermediate pressure chamber Pm from being excessively lowered, it is preferable to reduce the channel area of the intermediate pressure oil discharge channel 7u.

<Second addition mode>
In the second additional mode, as shown in FIG. 9, the intermediate pressure oil discharge flow path is configured so as to penetrate the shaft 4 from the radial center of the intermediate pressure chamber Pm to the oil discharge chamber 6e. ing.

  In this additional aspect, instead of the first oil passage 4h (see FIG. 1) drilled from the rear end surface 4b of the shaft body 4a toward the front in the axial direction, the front end in the axial direction from the rear end surface of the eccentric pin portion 4c. A third oil passage 4m drilled toward is provided. The third oil flow path 4m and the second oil flow path 4j communicate with each other at the tip portion, and as a whole, form an intermediate pressure oil discharge flow path from the rear end surface to the front end surface of the shaft body 4a.

  Further, a protruding portion 3f configured to cover the opening of the third oil passage 4m is provided at a portion of the end plate 3a of the movable scroll 3 facing the opening of the third oil passage 4m. Is provided.

  When the back pressure of the movable scroll 3 is in an appropriate state, the raised portion 3f provided on the end plate 3a of the movable scroll 3 is in a state of being separated axially rearward from the opening of the third oil passage 4m. The three oil flow path 4m opens to the intermediate pressure chamber Pm. In this state, the medium pressure oil in the medium pressure chamber Pm drops by a predetermined amount at the orifice 4k embedded in the front end of the second oil flow path 4j and is discharged to the intake chamber S through the oil discharge chamber 6e. As a result, the pressure (back pressure) in the intermediate pressure chamber Pm is properly maintained.

  Next, when the back pressure of the movable scroll 3 is insufficient, the movable scroll 3 is displaced toward the intermediate pressure chamber Pm, in other words, toward the shaft 4. Then, the raised portion 3f provided on the end plate 3a of the movable scroll 3 comes into contact with the opening of the third oil passage 4m, and the opening is closed. In this state, the medium pressure oil in the medium pressure chamber Pm is not discharged to the suction chamber S through the medium pressure oil discharge flow path, and as a result, the pressure (back pressure) in the medium pressure chamber Pm increases. Finally, it returns to an appropriate state. When the pressure in the intermediate pressure chamber Pm is restored to an appropriate back pressure, as described above, the raised portion 3f provided on the end plate 3a of the movable scroll 3 is the opening of the third oil flow path 4m. Since the intermediate pressure oil discharge channel opens to the intermediate pressure chamber Pm, the pressure in the intermediate pressure chamber Pm does not exceed the appropriate back pressure and become excessive pressure.

  The raised portion 3f may be formed integrally with the end plate 3a of the movable scroll 3, or may be formed as a separate member and attached to the end plate 3a of the movable scroll 3.

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Fixed scroll 3 Movable scroll 3f Raised part 4 Shaft 4h 1st oil flow path 4j 2nd oil flow path 4k Orifice 4m 3rd oil flow path 5 Electric motor 6 Front casing 6a Oil discharge chamber 7 Center casing (intermediate casing) )
7a Outer shell portion 7b Bearing support portion 7e Thrust receiving surface 7d High pressure oil supply flow path (high pressure fluid flow path)
7m Medium pressure oil supply channel (Medium pressure fluid channel)
7n Orifice 7u Medium pressure oil discharge flow path 8 Rear casing (discharge casing)
8a Discharge chamber 8c Oil storage chamber 8d High pressure oil supply passage 9 Thrust plate 20 Pressure adjustment plate 30 Ball valve 40 Spool valve C Compression chamber S Suction chamber Pm Medium pressure chamber

Claims (9)

A scroll compressor that performs a series of processes of suction, compression, and discharge of a working fluid by a revolving orbiting motion of a movable scroll with respect to a fixed scroll,
A back pressure chamber that is formed on the back side of the movable scroll and generates a back pressure that presses and urges the movable scroll toward the fixed scroll; and
An intermediate casing that houses the fixed scroll and the movable scroll and surrounds the back pressure chamber;
A discharge casing provided on the back side of the fixed scroll and forming a discharge chamber with the fixed scroll;
A thrust plate disposed between a thrust receiving surface formed on the intermediate casing and a back surface of the movable scroll;
A high-pressure fluid supply passage that is perforated in the discharge casing and supplies a high-pressure fluid from which the discharge pressure of the working fluid acts from the discharge chamber to the back pressure chamber;
A high-pressure fluid flow path drilled in the intermediate casing and supplying the high-pressure fluid to the back pressure chamber;
An intermediate pressure fluid flow path drilled in the intermediate casing and supplying the back pressure chamber as an intermediate pressure fluid by reducing the pressure of the high pressure fluid;
A member that switches between the flow and blockage of the high-pressure fluid from the high-pressure fluid flow path to the back pressure chamber by being displaced according to the axial displacement of the thrust plate accompanying the axial displacement of the movable scroll. A scroll compressor characterized by that. The intermediate casing includes a first end surface extending in a radial direction at a position farther from the movable scroll than the thrust receiving surface in the axial direction,
The high-pressure fluid flow path has an outlet opening in the first end face;
The member is disposed between the thrust plate and the first end surface, and is configured to open and close the outlet opening by being rotationally displaced according to an axial displacement of the thrust plate. The scroll compressor according to claim 1. The member includes an L-shaped plate including an opening / closing portion and a thrust receiving portion that are perpendicular to each other, and a compression spring, and the opening / closing portion is in contact with the first end surface to close the outlet opening. In an aspect in which the end of the thrust receiving portion is in contact with the thrust plate, the thrust receiving portion is disposed between the thrust plate and the first end surface.
The compression spring is interposed between the opening / closing portion and the thrust plate,
The intermediate casing further includes a second end face that is radially adjacent to the first end face and extends in the radial direction at a position farther from the movable scroll than the first end face in the axial direction.
3. The thrust receiving portion and the spring are located on opposite sides in the radial direction with reference to a corner portion formed between the first end surface and the second end surface. Scroll compressor described in 1.   The scroll compressor according to claim 3, wherein the compression spring has a repulsive force larger than a force obtained as a product of an area of the outlet opening and a pressure of the high-pressure fluid.   The opening / closing portion has a concave portion having a diameter larger than the outer diameter of the compression spring or a convex portion having a diameter smaller than the inner diameter of the compression spring at a portion in contact with the compression spring. The scroll compressor according to claim 3 or 4, characterized by the above.   The scroll compressor according to any one of claims 3 to 5, wherein the opening / closing part has a convex part loosely fitted in the outlet opening. The intermediate casing has a recess extending in the axial direction from the thrust receiving surface,
The member is disposed in the recess and is displaced in the axial direction in accordance with the axial displacement of the thrust plate, thereby preventing the high-pressure fluid from flowing from the high-pressure fluid flow path to the back pressure chamber. The scroll compressor according to claim 1, wherein the scroll compressor is configured to be switched. The high-pressure fluid channel is open to the recess;
The member includes a cylindrical valve housing, a valve body, and a compression spring,
The valve housing is disposed in the recess so that one end surface thereof is flush with the thrust receiving surface, an outlet channel extending from the end surface, and an inlet chamber communicating with the outlet channel; A valve seat is formed at a transition portion from the inlet chamber to the outlet channel by forming the inlet chamber with a larger diameter than the outlet channel,
The valve body is disposed in the inlet chamber and can contact with the valve seat, and a shaft portion that is formed integrally with the ball and configured to reciprocate in the outlet channel in the axial direction. Consisting of
The compression spring is interposed between the bottom of the recess and the ball,
The scroll compressor according to claim 7, wherein the shaft portion protrudes from the end face when the ball is in contact with the valve seat. The high-pressure fluid flow path intersects the recess,
The member includes a valve body configured to be capable of reciprocating in the axial direction in the recess, and a compression spring interposed between the bottom of the recess and the valve body,
When the through hole provided in the valve body is located at the intersection of the recess with the high-pressure fluid channel, the high-pressure fluid flows from the high-pressure fluid channel to the back pressure chamber,
The valve body protrudes from the thrust receiving surface when the through hole provided in the valve body is positioned on the thrust receiving surface side of the concave portion intersecting the high-pressure fluid flow path, The scroll compressor according to claim 7.

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