JP2014125908A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce time for which a movable scroll inclines while a scroll compressor operates, and to realize improvements in efficiency and reliability of the scroll compressor.SOLUTION: A scroll compressor (1) comprises a compression mechanism (14). In the compression mechanism (14), a compression chamber (50) is formed by engagement of laps (42, 52) of a fixed scroll (4) and a movable scroll (5). In the compression mechanism (14), a fixed-side slide-contact surface (84) of the fixed scroll (4) slidably contacts a movable-side end plate portion (51) of the movable scroll (5). A high pressure path (90) is formed in the fixed scroll (4). The high pressure path (90) has one end opening to the fixed-side slide contact surface (84) and the other end communicating with a high pressure chamber (45). As the movable scroll (5) inclines, high pressure gas refrigerant emitted from the high pressure path (90) flows into a second back pressure space (24) to raise a pressure of the second back pressure space (24). As a result, a pressing force acting on the movable scroll (5) increases.

Description

    The present invention relates to a scroll compressor having a fixed scroll and a movable scroll.

    Conventionally, scroll compressors that prevent the movable scroll from separating from the fixed scroll by applying a pressing force to the movable scroll toward the fixed scroll are known.

    In Patent Document 1, as an example, scroll compression in which a communicating path is provided in the end plate of the movable scroll to connect the compression chamber and the back pressure space, and refrigerant gas being compressed is introduced into the back pressure space on the back side of the movable scroll. A machine is disclosed. In this scroll compressor, the pressure of the refrigerant gas in the middle of compression (that is, intermediate pressure) is applied to the rear surface of the movable scroll, thereby pressing the movable scroll against the fixed scroll.

JP 2010-036441 A

  However, the conventional scroll compressor described above may fall into a state where a sufficient pressing force does not act on the movable scroll. Hereinafter, this problem will be described.

  Usually, a scroll compressor that applies an intermediate pressure to the back surface of the movable scroll is designed so that a sufficient pressing force acts on the movable scroll in a steady state where the operation state is kept constant. In other words, in the scroll compressor, the area of the back surface of the movable scroll where the intermediate pressure acts is set so that the pressing force acting on the movable scroll is larger than the force that pulls the movable scroll away from the fixed scroll. Is done.

  However, in a transient state where the operating state changes, the pressure in the back pressure space has not yet sufficiently increased even though the pressure of the refrigerant discharged from the compression chamber has already increased. There is. In such a situation, the pressing force acting on the movable scroll is insufficient, and the movable scroll is inclined with respect to the fixed scroll. When the movable scroll is tilted, the clearance between the movable scroll and the fixed scroll is increased, the amount of refrigerant leaking from the compression chamber is increased, and the efficiency of the scroll compressor is lowered.

  Further, when the movable scroll is tilted, the refrigerant leaks from the intermediate pressure back pressure space to the low pressure space or the compression chamber at the initial stage of the compression stroke, and the pressure in the back pressure space is reduced. When the pressure in the back pressure space is reduced, the pressing force acting on the movable scroll is reduced, and the inclination of the movable scroll is hardly eliminated. For this reason, even after the operation state of the scroll compressor becomes a steady state, the movable scroll remains inclined, and the efficiency of the scroll compressor may be lowered for a long time.

  The present invention has been made in view of the above points, and its purpose is to shorten the time during which the movable scroll is tilted during the operation of the scroll compressor, and to improve the efficiency and reliability of the scroll compressor. It is in.

  The first invention has a fixed scroll (4) and a movable scroll (5) each provided with a spiral wrap (42, 52), and the fixed scroll (4) and the movable scroll (5) A compression mechanism (14) in which a wrap (42, 52) meshes with each other to form a compression chamber (50); and a casing (10) that houses the compression mechanism (14), and the compression mechanism (14) includes: The present invention is intended for a scroll compressor that sucks and compresses low-pressure fluid into the compression chamber (50) and discharges the compressed high-pressure fluid from the compression chamber (50). The movable scroll (5) includes a movable side end plate portion (51) from which the wrap (52) protrudes from the front surface, and the front side of the movable side end plate portion (51) extends around the wrap (52). The surrounding portion is a movable side sliding contact surface (85) that is in sliding contact with the fixed side sliding contact surface (84) of the fixed scroll (4), while the compression mechanism (14) is the movable side of the movable scroll (5). Intermediate pressure for communicating the intermediate pressure space (24) facing the outer peripheral surface (56) and back surface (57) of the end plate part (51) and the compression chamber (50) in the middle of compression with the intermediate pressure space (24) The passage (48), the high-pressure space (45, 58) in which the internal pressure becomes the pressure of the high-pressure fluid, and one end of the passage (48) to the fixed-side sliding contact surface (84) or the movable-side sliding contact surface (85) A high-pressure passage (90) having an opening and the other end communicating with the high-pressure space (45, 58) is provided.

  In the first invention, the compression mechanism (14) is provided with the fixed scroll (4) and the movable scroll (5). The movable scroll (5) includes a movable end plate portion (51), and the movable side slide contact surface (85) of the movable side end plate portion (51) is fixed on the fixed side slide contact surface (84) of the fixed scroll (4). And slid.

  The compression mechanism (14) of the first invention is provided with an intermediate pressure space (24) and an intermediate pressure passage (48). The intermediate pressure space (24) can communicate with the compression chamber (50) in the middle of compression via the intermediate pressure passage (48). For this reason, the pressure in the intermediate pressure space (24) is higher than the pressure of the low pressure fluid sucked into the compression chamber (50) and lower than the pressure of the high pressure fluid discharged from the compression chamber (50). . The fluid pressure in the intermediate pressure space (24) acts on the back surface (57) of the movable side end plate portion (51) of the movable scroll (5). The movable scroll (5) is pressed against the fixed scroll (4) by the fluid pressure acting on the back surface (57) of the movable side end plate portion (51).

  The compression mechanism (14) of the first invention is provided with a high pressure space (45, 58) and a high pressure passage (90). One end of the high-pressure passage (90) opens to one of the fixed-side sliding contact surface (84) and the movable-side sliding contact surface (85). When the clearance between the fixed side sliding contact surface (84) and the movable side sliding contact surface (85) is appropriate, one end of the high pressure passage (90) is in a closed state. On the other hand, if the pressing force for pressing the movable scroll (5) against the fixed scroll (4) is insufficient, the movable scroll (5) may tilt. When the movable scroll (5) is tilted, the clearance between the fixed-side sliding contact surface (84) and the movable-side sliding contact surface (85) is expanded, and the high-pressure passage (90) communicates with the intermediate pressure space (24). In this state, the fluid in the high pressure space (45, 58) flows into the intermediate pressure space (24) through the high pressure passage (90), and the pressure in the intermediate pressure space (24) increases. When the pressure in the intermediate pressure space (24) increases, the pressing force acting on the movable scroll (5) increases, and the inclination of the movable scroll (5) is eliminated.

  In a second aspect based on the first aspect, either the fixed side sliding contact surface (84) or the movable side sliding contact surface (85) has the fixed side sliding contact surface (84) or the above For lead-out, which is formed so as to cross between the end of the high-pressure passage (90) opened to the movable side sliding contact surface (85) and the compression chamber (50) and can communicate with the intermediate pressure space (24) A recess (95) is provided.

  In the second aspect of the present invention, the lead-out recess (95) is provided on one of the fixed side sliding contact surface (84) and the movable side sliding contact surface (85). The lead-out recess (95) is formed so as to cross between the compression chamber (50) and one end of the high-pressure passage (90) that opens to the fixed-side sliding contact surface (84) or the movable-side sliding contact surface (85). Yes. For this reason, most of the fluid flowing out from the high-pressure passage (90) and flowing toward the compression chamber (50) flows into the lead-out recess (95). The lead-out recess (95) can communicate with the intermediate pressure space (24). Therefore, the fluid that has flowed into the outlet recess (95) is guided to the intermediate pressure space (24).

  In a third aspect based on the second aspect, the lead-out recess (95) is always in communication with the intermediate pressure space (24).

  In the third aspect of the invention, since the outlet recess (95) is always in communication with the intermediate pressure space (24), the fluid flowing into the outlet recess (95) surely flows into the intermediate pressure space (24).

  According to a fourth invention, in any one of the first to third inventions, the high-pressure space (45) is a space from which the compressed high-pressure fluid is discharged from the compression chamber (50). .

  In the fourth invention, when the movable scroll (5) is inclined, a part of the high-pressure fluid discharged from the compression chamber (50) flows into the intermediate pressure space (24) through the high-pressure passage (90). For this reason, when the movable scroll (5) tilts, a relatively large amount of high-pressure fluid flows through the high-pressure passage (90) into the intermediate pressure space (24) in a short time, and the pressure in the intermediate pressure space (24) is quickly increased. To rise.

  In a fifth aspect based on any one of the first to third aspects, the high-pressure passage (90) is provided in the fixed scroll (4) and opens to the fixed-side sliding contact surface (84). It is what.

  In the fifth invention, the high-pressure passage (90) is provided in the fixed scroll (4), and one end of the high-pressure passage (90) opens to the fixed-side sliding contact surface (84).

  In a sixth aspect based on any one of the first to third aspects, the high-pressure passage (90) is provided in the movable scroll (5) and opens to the movable side sliding contact surface (85). It is what.

  In the sixth aspect of the invention, the high pressure passage (90) is provided in the movable scroll (5), and one end of the high pressure passage (90) opens in the movable side sliding contact surface (85).

  A seventh invention includes the electric motor (6) housed in the casing (10) and driving the compression mechanism (14) in the first to fifth inventions, while the compression mechanism ( 14) is arranged on the back side of the movable scroll (5), and the space in the casing (10) is divided into a first space (16) on the compression mechanism (14) side and a second on the motor (6) side. A housing (3) partitioned into a space (17) is provided, and the first space (16) communicates with the intermediate pressure space (24).

  In the seventh invention, the compression mechanism (14) is provided with the housing (3). The space in the casing (10) is divided into a first space (16) and a second space (17) by the housing (3). The first space (16) on the compression mechanism (14) side communicates with the intermediate pressure space (24). When the pressure in the intermediate pressure space (24) varies, the pressure in the first space (16) also varies accordingly.

  In the present invention, the compression mechanism (14) is provided with the high-pressure passage (90). When the movable scroll (5) tilts and the clearance between the movable sliding contact surface (85) and the fixed sliding contact surface (84) increases, the intermediate pressure space (24) becomes the high pressure space via the high pressure passage (90). (45, 58), the pressure in the intermediate pressure space (24) increases.

  As described above, in the transient state where the operating state changes, the pressure in the intermediate pressure space (24) is still sufficient even though the pressure of the refrigerant discharged from the compression chamber (50) has already increased. You may fall into a situation that has not risen. In such a situation, the pressing force acting on the movable scroll (5) is insufficient, and the movable scroll (5) is inclined with respect to the fixed scroll (4). Further, even when the operating state of the scroll compressor (1) becomes a steady state, the pressing force acting on the movable scroll (5) remains insufficient, and the state in which the movable scroll (5) is tilted may continue for a long time.

  On the other hand, in the scroll compressor (1) of the present invention, when the movable scroll (5) is tilted with respect to the fixed scroll (4), the intermediate pressure space (24) passes through the high pressure passage (90). 45, 58), the pressure in the intermediate pressure space (24) rises. For this reason, after the pressing force acting on the movable scroll (5) is insufficient and the movable scroll (5) is tilted, the pressure in the intermediate pressure space (24) quickly rises and acts on the movable scroll (5). The pressing force increases rapidly. Therefore, according to the present invention, when the movable scroll (5) is tilted during the operation of the scroll compressor (1), the tilt of the movable scroll (5) can be quickly eliminated. As a result, fluid leakage from the compression chamber (50) due to the inclination of the movable scroll (5) can be suppressed, and the efficiency of the scroll compressor (1) can be improved.

  Here, in the state in which the movable scroll (5) is inclined, the fluid flowing out from the high-pressure passage (90) into the gap between the fixed side sliding contact surface (84) and the movable side sliding contact surface (85) It flows not only to the intermediate pressure space (24) located on the outer peripheral side of 51) but also toward the compression chamber (50) located on the center side of the movable end plate portion (51). The fluid flowing out of the high pressure passage (90) may include high pressure fluid compressed by the compression mechanism (14) and discharged from the compression chamber (50). In that case, when the high-pressure fluid discharged from the compression chamber (50) returns to the compression chamber (50) again, the flow rate of the high-pressure fluid discharged to the outside of the scroll compressor (1) decreases, and the scroll compressor (1 ) Decreases in efficiency.

  On the other hand, in the second aspect of the present invention, the lead-out recess (95) is provided on either the fixed side sliding contact surface (84) or the movable side sliding contact surface (85). Then, most of the fluid flowing out from the high-pressure passage (90) and flowing toward the compression chamber (50) flows into the outlet recess (95) and is guided to the intermediate pressure space (24). Therefore, according to the present invention, the amount of fluid that flows out from the high-pressure passage (90) and returns to the compression chamber (50) can be reduced, and the scroll compression caused by flowing out the fluid from the high-pressure passage (90). The reduction in efficiency of the machine (1) can be suppressed.

  In the compression mechanism (14) of the second invention, not only the fluid flowing out from the high-pressure passage (90) and flowing to the outer peripheral side of the movable end plate portion (51) but also flowing out from the high-pressure passage (90) and compressed The fluid flowing toward the chamber (50) also flows into the intermediate pressure space (24) through the outlet recess (95). Accordingly, when the movable scroll (5) is tilted, the pressure in the intermediate pressure space (24) can be increased more quickly, and the time during which the movable scroll (5) is tilted can be further shortened.

  In the third invention, the lead-out recess (95) is always in communication with the intermediate pressure space (24). For this reason, compared with the case where the outlet recess (95) intermittently communicates with the intermediate pressure space (24), the fluid flowing into the outlet recess (95) can be reliably fed into the intermediate pressure space (24). .

  In the fourth invention, the high-pressure passage (90) communicates with the high-pressure space (45), which is a space from which the compressed high-pressure fluid is discharged from the compression chamber (50). For this reason, when the movable scroll (5) is tilted, the pressure in the intermediate pressure space (24) can be quickly increased, and as a result, the pressing force acting on the movable scroll (5) can be quickly increased. Can do. Therefore, according to the present invention, the inclination of the movable scroll (5) can be quickly eliminated, and the decrease in efficiency of the scroll compressor (1) can be more reliably suppressed.

  Here, in the scroll compressor (1), the pressure in the intermediate pressure space (24) may fluctuate due to some factor even in the steady operation state. When the pressure in the intermediate pressure space (24) varies, the magnitude of the pressing force acting on the movable scroll (5) also varies, and the movable scroll (5) may be tilted.

  On the other hand, in the seventh invention, the space in the casing (10) is partitioned into the first space (16) and the second space (17), and the first space (16) communicates with the intermediate pressure space (24). For this reason, compared with the case where the intermediate pressure space (24) is not in communication with the first space (16), the fluctuation of the pressure in the intermediate pressure space (24) becomes moderate. Therefore, according to the present invention, the fluctuation of the pressure in the intermediate pressure space (24) can be moderated, and the fluctuation range of the magnitude of the pressing force acting on the movable scroll (5) can be suppressed. As a result, the inclination of the movable scroll (5) can be suppressed, and the efficiency and reliability of the scroll compressor (1) can be improved.

FIG. 1 is a longitudinal sectional view of the scroll compressor according to the first embodiment. FIG. 2 is an enlarged cross-sectional view of the compression mechanism of FIG. 1 and shows a state in which the entire lead-out groove is covered with the movable side end plate portion. FIG. 3 is an enlarged cross-sectional view of the compression mechanism of FIG. 1 and shows a state in which a part of the outlet groove is exposed to the second back pressure space. 4A and 4B are views showing the housing, in which FIG. 4A is a plan view, and FIG. 4B is a cross-sectional view showing a bb cross section of FIG. FIG. 5 is a bottom view of the fixed scroll according to the first embodiment. 6 is an enlarged longitudinal sectional view showing the main part of the compression mechanism of FIG. 2, in which (A) shows a normal state in which the movable scroll is pressed against the fixed scroll, and (B) shows that the movable scroll is tilted. Indicates the overturned state. FIG. 7 is a bottom view of the fixed scroll according to the first modification of the first embodiment. FIG. 8 is a bottom view of the fixed scroll according to the first modification of the first embodiment. FIG. 9 is a bottom view of the fixed scroll according to the second modification of the first embodiment. FIG. 10 is a vertical cross-sectional view of a compression mechanism of Modification 3 of Embodiment 1. FIG. 11 is a longitudinal sectional view showing the compression mechanism of the second embodiment. FIG. 12 is a plan view of the movable scroll according to the second embodiment. FIG. 13 is a plan view of the movable scroll according to the first modification of the second embodiment. FIG. 14 is a plan view of the movable scroll according to the second modification of the second embodiment. FIG. 15 is a longitudinal sectional view showing a compression mechanism of the third embodiment. FIG. 16 is a plan view illustrating a main part of the movable scroll according to the third embodiment. FIG. 17 is a longitudinal sectional view showing a compression mechanism of the fourth embodiment. FIG. 18 is a bottom view illustrating a main part of the fixed scroll according to the fourth embodiment.

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

Embodiment 1 of the Invention
As shown in FIGS. 1 and 2, the scroll compressor (1) according to the present embodiment is connected to a refrigerant circuit (not shown) that circulates refrigerant and performs a refrigeration cycle, and compresses refrigerant that is fluid. It is.

<Overall configuration of scroll compressor>
The scroll compressor (1) includes a compression mechanism (14) that sucks and compresses a refrigerant, and a fully-enclosed type that includes a casing (10) formed in a vertically long hollow cylinder that accommodates the compression mechanism (14). It is a compressor.

  The casing (10) is a pressure vessel constituted by a casing body (11), an upper wall portion (12), and a bottom wall portion (13). The casing body (11) is a cylindrical body having an axis extending in the vertical direction. The upper wall portion (12) is formed in a bowl shape having a convex surface protruding upward, and is welded to the upper end portion of the casing body (11) in an airtight manner. The bottom wall portion (13) is formed in a bowl shape having a convex surface protruding downward, and is welded to the lower end portion of the casing body (11) in an airtight manner.

  Housed in the casing (10) are a compression mechanism (14) and an electric motor (6) that drives the compression mechanism (14). The electric motor (6) is disposed below the compression mechanism (14). The compression mechanism (14) and the electric motor (6) are connected by a drive shaft (7) disposed so as to extend in the vertical direction in the casing (10).

  An oil reservoir (15) in which lubricating oil is stored is formed at the bottom of the casing (10).

  The upper wall (12) of the casing (10) is provided with a suction pipe (18) for introducing the refrigerant of the refrigerant circuit into the compression mechanism (14). The casing body (11) is provided with a discharge pipe (19) for leading the refrigerant in the casing (10) out of the casing (10).

  The drive shaft (7) includes a main shaft portion (71), an eccentric portion (72), and a counterweight portion (73). The eccentric part (72) is formed in a relatively short shaft shape, and projects from the upper end of the main shaft part (71). The shaft center of the eccentric portion (72) is eccentric by a predetermined distance r with respect to the shaft center of the main shaft portion (71). That is, in the drive shaft (7), the eccentric amount of the eccentric portion (72) with respect to the main shaft portion (71) is “r”. The counterweight portion (73) is provided on the main shaft portion (71) in order to achieve a dynamic balance with a movable scroll (5), an eccentric portion (72) and the like which will be described later. An oil supply path (74) extending from the upper end to the lower end is formed in the drive shaft (7). The lower end of the drive shaft (7) is immersed in the oil reservoir (15).

  The electric motor (6) includes a stator (61) and a rotor (62). The stator (61) is fixed to the casing body (11) by shrink fitting or the like. The rotor (62) is disposed inside the stator (61) and is fixed to the main shaft portion (71) of the drive shaft (7). The rotor (62) is arranged substantially coaxially with the main shaft portion (71).

  A lower bearing member (21) is provided in the lower part of the casing (10). The lower bearing member (21) is fixed near the lower end of the casing body (11). A through hole is formed in the central portion of the lower bearing member (21), and the drive shaft (7) is inserted through the through hole. The lower bearing member (21) rotatably supports the lower end portion of the drive shaft (7).

<Configuration of compression mechanism>
The compression mechanism (14) includes a housing (3), a fixed scroll (4), and a movable scroll (5). The housing (3) is fixed to the casing body (11). The fixed scroll (4) is disposed on the upper surface of the housing (3). The movable scroll (5) is disposed between the fixed scroll (4) and the housing (3).

  As shown in FIG. 4, the housing (3) is formed in a dish shape with a recessed center. The housing (3) includes an annular portion (31) on the outer peripheral side and a concave portion (32) on the inner peripheral side.

  As shown in FIGS. 1 and 2, the housing (3) is press-fitted and fixed to the upper end edge of the casing body (11). Specifically, the outer peripheral surface of the annular portion (31) of the housing (3) is in close contact with the inner peripheral surface of the casing body (11) over the entire periphery. The housing (3) partitions the internal space of the casing (10) into an upper space (16) and a lower space (17). The upper space (16) is a first space on the compression mechanism (14) side. The lower space (17) is a second space in which the electric motor (6) is accommodated.

  The housing (3) is formed with a through hole (33) penetrating from the bottom of the recess (32) to the lower end. A bearing metal (20) is inserted into the through hole (33). The drive shaft (7) is inserted through the bearing metal (20). The housing (3) constitutes an upper bearing that rotatably supports the upper end portion of the drive shaft (7).

  The fixed scroll (4) includes a fixed side end plate portion (41), a fixed side wrap (42), and an outer peripheral wall portion (43). The stationary side wrap (42) is formed in a spiral wall shape that draws an involute curve, and projects from the front surface (lower surface in FIG. 2) of the stationary side end plate portion (41). The outer peripheral wall portion (43) is formed so as to surround the outer peripheral side of the fixed side wrap (42) and protrudes from the front surface of the fixed side end plate portion (41). The distal end surface of the fixed side wrap (42) and the distal end surface of the outer peripheral wall portion (43) are substantially flush. The fixed scroll (4) is fixed to the housing (3).

  The movable scroll (5) includes a movable side end plate portion (51), a movable side wrap (52), and a boss portion (53). The movable side end plate portion (51) is formed in a substantially circular flat plate shape. The fixed side wrap (42) is formed in a spiral wall shape that draws an involute curve, and protrudes from the front surface (upper surface in FIG. 2) of the movable side end plate portion (51). The boss portion (53) is formed in a cylindrical shape, and is arranged at the center of the back surface (57) of the movable side end plate portion (51).

  The movable side wrap (52) of the movable scroll (5) is engaged with the fixed side wrap (42) of the fixed scroll (4). In the compression mechanism (14), the fixed-side end plate portion (41) and the fixed-side wrap (42) of the fixed scroll (4), and the movable-side end plate portion (51) and the movable-side wrap (52) of the movable scroll (5). ) And the compression chamber (50) is formed.

  The protruding end surface (the lower surface in FIG. 2) of the outer peripheral wall portion (43) of the fixed scroll (4) has a portion along the inner peripheral edge of the outer peripheral wall portion (43), and the movable end plate portion (51) of the movable scroll (5). ) And the fixed side sliding contact surface (84). Further, on the front surface (upper surface in FIG. 2) of the movable side end plate portion (51) of the movable scroll (5), the portion surrounding the movable side wrap (52) is fixed on the fixed side sliding contact surface of the fixed scroll (4) ( 84) and a movable side sliding contact surface (85).

  A suction port (25) is formed in the outer peripheral wall (43) of the fixed scroll (4). A downstream end of the suction pipe (18) is connected to the suction port (25). The suction pipe (18) passes through the upper wall (12) of the casing (10) and extends to the outside of the casing (10). A discharge port (44) penetrating the fixed side end plate part (41) is formed in the center of the fixed side end plate part (41) of the fixed scroll (4).

  A high-pressure chamber (45) is formed at the center of the back surface (upper surface in FIG. 2) of the fixed-side end plate portion (41). A discharge port (44) is opened in the high pressure chamber (45). The high pressure chamber (45) constitutes a high pressure space.

  The fixed scroll (4) is formed with a first flow passage (46) communicating with the high-pressure chamber (45). The first flow passage (46) extends radially outward from the high-pressure chamber (45) on the back surface of the fixed-side end plate portion (41), and in the outer peripheral wall portion (43) at the outer peripheral portion of the fixed-side end plate portion (41). And is open to the protruding end surface (the lower surface in FIG. 2) of the outer peripheral wall portion (43). A cover member (47) for closing the high-pressure chamber (45) and the first flow passage (46) is attached to the back surface of the fixed-side end plate portion (41). The cover member (47) hermetically isolates the high pressure chamber (45) and the first flow passage (46) from the upper space (16), and is discharged into the high pressure chamber (45) and the first flow passage (46). The refrigerant gas does not leak into the upper space (16).

  The fixed side end plate portion (41) is provided with a flow mechanism for guiding the refrigerant from the compression chamber (50) and to the upper space (16) of the casing (10). The flow mechanism is for communicating between the back pressure space (24) and the upper space (16) and the compression chamber (50) in the middle of compression. The compression chamber (50) and the upper space (16) are connected to each other. An intermediate pressure passage (48) is provided. That is, the volume of the compression chamber (50) is gradually reduced until it is opened to the discharge port (44) after being closed. The end of the intermediate pressure passage (48) on the compression chamber (50) side is provided so as to open to the compression chamber (50) in the intermediate pressure state having a predetermined volume.

  A reed valve (49) is provided on the back surface of the fixed side end plate portion (41) of the fixed scroll (4). The reed valve (49) is a check valve that opens and closes the opening on the upper space (16) side of the intermediate pressure passage (48). When the pressure in the compression chamber (50) becomes higher than the pressure in the upper space (16) by a predetermined value, the reed valve (49) is opened, otherwise, the reed valve (49) is closed. When the reed valve (49) is opened, the compression chamber (50) and the upper space (16) communicate with each other via the intermediate pressure passage (48). As a result, the pressure in the upper space (16) is higher than the pressure (suction pressure) of the low-pressure gas refrigerant sucked into the compression chamber (50), and the pressure (discharge) of the high-pressure gas refrigerant discharged from the compression chamber (50). Intermediate pressure lower than (pressure).

  As shown in FIG. 4, the annular part (31) of the housing (3) is provided with four attachment parts (34, 34,...) For placing the fixed scroll (4). These mounting portions (34, 34,...) Are provided with screw holes, and the fixed scroll (4) is fixed by bolts.

    In one of the attachment portions (34, 34,...), A second flow passage (39) is formed so as to penetrate the annular portion (31). The second flow passage (39) is formed at a position communicating with the first flow passage (46) of the fixed scroll (4) when the fixed scroll (4) is attached to the housing (3). The refrigerant gas discharged from the compression chamber (50) to the high-pressure chamber (45) flows through the first flow passage (46) and the second flow passage (39) in this order and flows into the lower space (17) of the casing (10). To do.

  On the inner peripheral side of the annular portion (31), an inner peripheral wall portion (35) formed in an annular shape so as to surround the central concave portion (32) is formed. The inner peripheral wall portion (35) is formed lower than the attachment portions (34, 34,...) And higher than the other portions of the annular portion (31).

  A seal groove (36) is formed annularly along the inner peripheral wall portion (35) on the protruding end surface (the upper surface in FIG. 2) of the inner peripheral wall portion (35). As shown in FIG. 2, an annular seal ring (37) is fitted in the seal groove (36). The seal ring (37) contacts the back surface (57) of the movable side end plate part (51) of the movable scroll (5) and seals the gap between the housing (3) and the movable side end plate part (51).

  In the compression mechanism (14), a back pressure space (22) is formed between the housing (3) and the fixed scroll (4). The back pressure space (22) is divided into a first back pressure space (23) on the inner peripheral side of the seal ring (37) and a second back surface on the outer peripheral side of the seal ring (37) by the seal ring (37). It is partitioned into a pressure space (24).

  The first back pressure space (23) communicates with the lower space (17) of the casing (10) through a gap between the bearing metal (20) and the drive shaft (7). Although not shown, the housing (3) is formed with an oil drain passage that opens to the bottom of the first back pressure space (23). The drainage passage allows the first back pressure space (23) to communicate with the lower space (17), and the lubricating oil in the first back pressure space (23) is discharged to the lower space (17).

  The eccentric part (72) of the drive shaft (7) and the boss part (53) of the movable scroll (5) are located in the first back pressure space (23). An eccentric part (72) is rotatably inserted into the boss part (53) of the movable scroll (5). An oil supply passage (74) is opened at the upper end of the eccentric portion (72). That is, high-pressure lubricating oil is supplied from the oil supply passage (74) into the boss portion (53), and the sliding surfaces of the boss portion (53) and the eccentric portion (72) are lubricated by the lubricating oil. The boss inner space (58) formed between the upper end surface of the eccentric portion (72) and the back surface (57) of the movable side end plate portion (51) constitutes a high-pressure space.

  The second back pressure space (24) is a space facing the outer peripheral surface (56) and the back surface (57) of the movable side end plate portion (51), and constitutes an intermediate pressure space. The second back pressure space (24) communicates with the upper space (16) through a gap between the housing (3) and the fixed scroll (4).

  The attachment portions (34, 34,...) Of the housing (3) to which the fixed scroll (4) is attached project upward in the annular portion (31) as shown in FIG. For this reason, a gap is formed between the fixed scroll (4) and the annular portion (31) of the housing (3) at portions other than the mounting portions (34, 34,...). The second back pressure space (24) and the upper space (16) communicate with each other through this gap.

  An Oldham coupling (55) is provided in the second back pressure space (24). The Oldham coupling (55) is formed in the keyway (54) formed on the back surface (57) of the movable side end plate portion (51) of the movable scroll (5) and the annular portion (31) of the housing (3). Engages with the keyway (38, 38) to regulate the rotation of the movable scroll (5).

<High-pressure passage and outlet groove>
As shown in FIGS. 2 and 5, the compression mechanism (14) is formed with a high-pressure passage (90) and a lead-out groove (95).

  The high-pressure passage (90) is formed in the outer peripheral wall (43) of the fixed scroll (4) (see FIG. 2). The high-pressure passage (90) is an elongated hole having a circular cross section that passes through the outer peripheral wall (43). One end of the high-pressure passage (90) is an opening end (91) that opens to the fixed-side sliding contact surface (84). On the other hand, the other end of the high pressure passage (90) communicates with the first flow passage (46). The other end of the high pressure passage (90) communicates with the high pressure chamber (45), which is a high pressure space, via the first flow passage (46).

  On the fixed side sliding contact surface (84) of the fixed scroll (4), the open end (91) of the high-pressure passage (90) is disposed inside a circle Q indicated by a two-dot chain line in FIG. The portion inside the circle Q of the fixed side sliding contact surface (84) is the portion that is always in sliding contact with the movable side sliding contact surface (85) of the movable scroll (5). Therefore, the open end (91) of the high-pressure passage (90) always faces the movable sliding contact surface (85). On the other hand, the portion of the fixed side sliding contact surface (84) outside the circle Q is a portion that intermittently contacts the movable side sliding contact surface (85). That is, during the rotation of the drive shaft (7) that drives the movable scroll (5), the portion outside the circle Q of the fixed-side sliding contact surface (84) temporarily becomes the second back pressure space (24 ) Exposed.

  The lead-out groove (95) is a concave groove formed in the fixed side sliding contact surface (84) of the fixed scroll (4) (see FIG. 5). The lead-out groove (95) is formed in a U shape surrounding the compression chamber (50) side of the open end (91) of the high-pressure passage (90). Further, both ends of the U-shaped lead-out groove (95) are located outside the circle Q shown in FIG. Therefore, as shown in FIGS. 2 and 3, both ends of the lead-out groove (95) are intermittently exposed to the second back pressure space (24). Thus, the lead-out groove (95) is formed so as to cross between the open end (91) of the high-pressure passage (90) and the compression chamber (50), and can communicate with the second back pressure space (24). It has become.

  The lead-out groove (95) is a concave groove for collecting the high-pressure gas refrigerant flowing out from the high-pressure passage (90) and guiding it to the second back pressure space (24), and constitutes a lead-out recess. The lead-out groove (95) is a groove having a width W of about 2 mm and a depth D of about 2 mm (see FIG. 6). Note that the values of the width W and the depth D of the derivation groove (95) shown here are merely examples.

-Operation of scroll compressor-
The operation of the scroll compressor (1) will be described.

<Operation to compress refrigerant>
When the electric motor (6) is operated, the movable scroll (5) of the compression mechanism (14) is driven by the drive shaft (7). The movable scroll (5) revolves around the axis of the drive shaft (7) while being prevented from rotating by the Oldham coupling (55). When the movable scroll (5) revolves, the low-pressure gas refrigerant flowing from the suction pipe (18) is sucked into the compression chamber (50) of the compression mechanism (14) and compressed.

  The compressed refrigerant (that is, high-pressure gas refrigerant) is discharged from the discharge port (44) of the fixed scroll (4) to the high-pressure chamber (45). The high-pressure refrigerant gas that has flowed into the high-pressure chamber (45) passes through the first flow passage (46) of the fixed scroll (4) and the second flow passage (39) of the housing (3) in this order, and the casing (10) To the lower space (17). Then, the refrigerant gas flowing out into the lower space (17) is discharged to the outside of the casing (10) through the discharge pipe (19).

<Pressing the movable scroll against the fixed scroll>
The lower space (17) of the casing (10) has a pressure equivalent to the high-pressure gas refrigerant discharged from the compression mechanism (14) (that is, discharge pressure). Accordingly, the pressure of the lubricating oil stored in the oil reservoir (15) below the lower space (17) is also substantially equal to the discharge pressure.

  The high-pressure lubricating oil present in the oil reservoir (15) flows from the downstream end of the oil supply passage (74) of the drive shaft (7) toward the upstream end, and the upper end of the eccentric portion (72) of the drive shaft (7). It flows into the boss internal space (58) of the movable scroll (5) from the opening. The lubricating oil supplied to the boss inner space (58) lubricates the sliding surfaces of the boss part (53) and the eccentric part (72) and flows out to the first back pressure space (23). The lubricating oil flowing into the first back pressure space (23) is discharged to the lower space (17) through an oil drain passage (not shown). The first back pressure space (23) communicates with the lower space (17) through the oil drainage passage. Accordingly, the pressure in the first back pressure space (23) is substantially equal to the discharge pressure.

  An intermediate pressure passage (48) is formed in the fixed side end plate portion (41) of the fixed scroll (4). Therefore, when the reed valve (49) is opened, a part of the refrigerant being compressed in the compression chamber (50) of the compression mechanism (14) passes through the intermediate pressure passage (48) in the casing (10). It flows into the upper space (16). The upper space (16) communicates with the second back pressure space (24) on the back side of the movable scroll (5). Therefore, the pressure in the second back pressure space (24) is equal to the pressure of the gas refrigerant in the middle of compression (ie, intermediate pressure).

  On the back surface (57) of the movable side end plate portion (51) of the movable scroll (5), the fluid pressure (discharge pressure) in the first back pressure space (23) and the fluid in the second back pressure space (24) Pressure (intermediate pressure) acts. Therefore, an axial pressing force that presses the movable scroll (5) toward the fixed scroll (4) acts on the movable scroll (5).

  Here, the refrigerant pressure in the compression chamber (50) acts on the front surface of the movable side end plate portion (51) of the movable scroll (5). For this reason, an axial force (separation force) that tries to separate the movable scroll (5) from the fixed scroll (4) acts on the movable scroll (5). In the compression mechanism (14), a pressing force acts on the movable scroll (5), and the movable scroll (5) is pressed against the fixed scroll (4) against the separation force. As a result, the inclination (rollover) of the movable scroll (5) due to the separation force is prevented.

  If the pressing force is too large with respect to the separation force, the frictional force acting on the fixed scroll (4) and the movable scroll (5) increases, and the loss due to the frictional force increases and the scroll compressor The efficiency of (1) will decrease. Conversely, if the pressing force is too small relative to the separation force, the movable scroll (5) tends to tilt and the amount of refrigerant leakage from the compression chamber (50) increases, resulting in the performance of the scroll compressor (1). Further, the fixed scroll (4) and the movable scroll (5) are unevenly worn, and the reliability of the scroll compressor (1) is lowered.

  In the scroll compressor (1) of the present embodiment, the ratio of the area of the portion where the discharge pressure acts to the area of the portion where the intermediate pressure acts on the back of the movable scroll (5) is formed in the fixed scroll (4). By appropriately adjusting the opening position of the intermediate pressure passage (48) on the compression chamber (50) side and the opening pressure of the reed valve (49) provided on the fixed scroll (4), an appropriate pressing force can be applied to the movable scroll (5). To be granted.

<Operation to eliminate tilt of movable scroll>
As described above, the scroll compressor (1) of the present embodiment is designed so that the pressing force acting on the movable scroll (5) has an appropriate magnitude. For this reason, the movable scroll (5) tilts if it is operated within the range of operating conditions assumed at the time of design and the operating state such as the rotational speed of the electric motor (6) is kept constant. There is almost no.

  However, in a transient state where the operating state of the scroll compressor (1) is changing (that is, a state in the middle of transition from one steady state to another steady state), the pressing force acting on the movable scroll (5) is , There may be a temporary shortage of separation force. For example, the refrigerant pressure (that is, the intermediate pressure) in the second back pressure space (24) is still sufficiently high even though the refrigerant pressure in the compression chamber (50) has already increased due to the change of the operating state. When it is not raised, the pressing force acting on the movable scroll (5) is insufficient, and the movable scroll (5) may be tilted. Further, even when the operating state of the scroll compressor (1) becomes a steady state, the pressing force acting on the movable scroll (5) remains insufficient, and the state in which the movable scroll (5) is tilted may continue for a long time.

  On the other hand, in the scroll compressor (1) of the present embodiment, the compression mechanism (14) is provided with a high-pressure passage (90). For this reason, if the movable scroll (5) tilts during operation of the scroll compressor (1), the tilt of the movable scroll (5) is quickly eliminated, and the movable scroll (5) is fixed to the fixed scroll (4). Return to the state where it was pressed. Here, the operation for eliminating the tilt of the movable scroll (5) will be described with reference to FIG.

  FIG. 6A shows a state in which the movable scroll (5) is not inclined, that is, a normal state in which the movable scroll (5) is pressed against the fixed scroll (4). In this normal state, the clearance between the fixed side sliding contact surface (84) of the fixed scroll (4) and the movable side end plate (51) of the movable scroll (5) is the clearance between the fixed side sliding contact surface (84) and the movable side sliding contact. It is generally constant over the entire contact surface (85). An oil film (81) made of lubricating oil is formed between the fixed side sliding contact surface (84) and the movable side sliding contact surface (85).

  As described above, the open end (91) of the high-pressure passage (90) in the fixed side sliding contact surface (84) always faces the movable side sliding contact surface (85). Further, the gap between the fixed side sliding contact surface (84) and the movable side sliding contact surface (85) is sealed by the oil film (81). Therefore, in the normal state shown in FIG. 6A, the open end (91) of the high-pressure passage (90) is closed, and the high-pressure gas refrigerant does not flow out from the high-pressure passage (90).

  On the other hand, FIG. 6B shows an overturned state in which the movable scroll (5) is tilted. In this overturned state, the clearance between the fixed side sliding contact surface (84) of the fixed scroll (4) and the movable side end plate part (51) of the movable scroll (5) is directed toward the outer peripheral side of the movable side end plate part (51). Gradually expand. Further, in the vicinity of the opening end (91) of the high-pressure passage (90), the clearance between the fixed side sliding contact surface (84) and the movable side end plate portion (51) is enlarged, and the sealing effect by the oil film (81) is lost. For this reason, the open end (91) of the high-pressure passage (90) communicates with the second back pressure space (24) via the gap between the fixed-side sliding contact surface (84) and the movable-side end plate portion (51). A part of the high-pressure gas refrigerant in the high-pressure chamber (45) flows into the second back pressure space (24) through the high-pressure passage (90).

  When the high-pressure gas refrigerant flows into the second back pressure space (24), the pressure in the second back pressure space (24) increases. Then, the refrigerant pressure that acts on the back surface (57) of the movable side end plate portion (51) increases, and the pressing force that acts on the movable scroll (5) increases. As a result, the movable scroll (5) is pressed against the fixed scroll (4) against the separating force, and the inclination of the movable scroll (5) is eliminated. That is, the movable side end plate portion (51) returns from the posture shown in FIG. 6 (B) to the posture shown in FIG.

  By the way, as shown in FIG. 6 (B), the high-pressure gas refrigerant that has flowed out of the open end (91) of the high-pressure passage (90) flows into the second back pressure space (on the outer peripheral side of the movable side end plate portion (51)). 24) As well as flowing toward the compression chamber (50) located on the center side of the movable end plate (51). When the high-pressure gas refrigerant discharged from the compression chamber (50) returns to the compression chamber (50) again, the flow rate of the high-pressure gas refrigerant discharged from the discharge pipe (19) to the outside of the casing (10) decreases. The efficiency of the scroll compressor (1) decreases.

  On the other hand, in the scroll compressor (1) of the present embodiment, a lead-out groove (95) is provided on the fixed side sliding contact surface (84) of the fixed scroll (4). For this reason, the amount of high-pressure gas refrigerant flowing into the compression chamber (50) from the open end (91) of the high-pressure passage (90) is reduced. Here, this point will be described with reference to FIG.

  Part of the high-pressure gas refrigerant that has flowed out of the open end (91) of the high-pressure passage (90) passes through the gap between the fixed sliding surface (84) and the movable end plate (51) to the compression chamber (50) side. Flowing. On the other hand, the depth D of the lead-out groove (95) is sufficiently larger than the clearance between the fixed side sliding contact surface (84) and the movable side end plate portion (51). For this reason, most of the high-pressure gas refrigerant that has reached the lead-out groove (95) through the gap between the fixed-side sliding contact surface (84) and the movable-side end plate part (51) enters the lead-out groove (95). Inflow. The amount of high-pressure gas refrigerant that further flows through the narrow gap between the fixed-side sliding contact surface (84) and the movable-side end plate portion (51) and reaches the compression chamber (50) is extremely small. Therefore, a decrease in efficiency of the scroll compressor (1) is suppressed.

  The end of the lead-out groove (95) is intermittently exposed to the second back pressure space (24). For this reason, the high-pressure gas refrigerant that has flowed into the outlet groove (95) flows into the second back pressure space (24) from the end of the outlet groove (95). As described above, the high-pressure gas refrigerant flowing out from the open end (91) of the high-pressure passage (90) flows not only toward the second back pressure space (24) but also toward the compression chamber (50). Also flows into the second back pressure space (24) through the outlet groove (95). Therefore, most of the high-pressure gas refrigerant that has flowed out of the open end (91) of the high-pressure passage (90) flows into the second back pressure space (24), and the pressure in the second back pressure space (24) is more rapidly increased. To rise. Therefore, the time during which the movable scroll (5) is tilted is further shortened.

-Effect of Embodiment 1-
In the scroll compressor (1) of the present embodiment, the compression mechanism (14) is provided with a high-pressure passage (90). When the movable scroll (5) tilts due to insufficient pressing force acting on the movable scroll (5) during the operation of the scroll compressor (1), the high pressure that flows out from the open end (91) of the high-pressure passage (90) A gas refrigerant is supplied to the second back pressure space (24). Therefore, according to this embodiment, when the movable scroll (5) tilts, the pressure of the second back pressure space (24) can be quickly increased. Therefore, the pressing force acting on the movable scroll (5) can be quickly increased, and the time during which the movable scroll (5) is tilted can be shortened. As a result, refrigerant leakage from the compression chamber (50) due to the inclination of the movable scroll (5) can be suppressed, and the efficiency of the scroll compressor (1) can be improved. Further, uneven wear of the fixed scroll (4) and the movable scroll (5) due to the inclination of the movable scroll (5) can be suppressed, and the reliability of the scroll compressor (1) can be improved.

  Further, in the compression mechanism (14) of the present embodiment, the lead-out groove (95) is formed in the fixed side sliding contact surface (84) of the fixed scroll (4). Then, in a state where the movable scroll (5) is inclined, the high-pressure gas refrigerant flowing out from the open end (91) of the high-pressure passage (90) and going to the compression chamber (50) is collected into the outlet groove (95). It is supplied to the second back pressure space (24). Therefore, according to the present embodiment, the amount of high-pressure gas refrigerant that flows out from the high-pressure passage (90) and returns to the compression chamber (50) can be reduced, and the high-pressure gas refrigerant flows out from the high-pressure passage (90). The reduction in the efficiency of the scroll compressor (1) due to this can be suppressed.

  Further, according to the present embodiment, most of the high-pressure gas refrigerant flowing out from the open end (91) of the high-pressure passage (90) can be supplied to the second back pressure space (24), and the second back pressure space can be supplied. The pressure of (24) can be increased more rapidly. Therefore, according to this embodiment, the time during which the movable scroll (5) is tilted can be further shortened.

  The high-pressure passage (90) of the present embodiment communicates with the high-pressure chamber (45) from which the high-pressure gas refrigerant is discharged from the compression chamber (50). When the movable scroll (5) is tilted, the high-pressure gas refrigerant in the high-pressure chamber (45) flows into the second back pressure space (24) through the high-pressure passage (90). For this reason, compared with the case where the high-pressure passage (90) communicates with a space where a large amount of high-pressure refrigerating machine oil is present, a relatively large amount of high-pressure gas refrigerant can be quickly removed from the second back when the movable scroll (5) is inclined. It can be introduced into the pressure space (24). When a relatively large amount of high-pressure gas refrigerant flows into the second back pressure space (24) in a short time, the pressure in the second back pressure space (24) rises quickly, and the pressing force acting on the movable scroll (5) is increased. Increases quickly. Therefore, according to this embodiment, the inclination of the movable scroll (5) can be quickly eliminated, and the reduction in efficiency of the scroll compressor (1) due to the inclination of the movable scroll (5) can be more reliably reduced. .

  Here, in the scroll compressor (1), the pressure in the second back pressure space (24) may fluctuate due to some factor even in the steady operation state. When the pressure in the second back pressure space (24) varies, the magnitude of the pressing force acting on the movable scroll (5) also varies, and the movable scroll (5) may tilt.

  On the other hand, in the scroll compressor (1) of this embodiment, the space in the casing (10) is partitioned into a first space (16) and a second space (17), and the first space (16) is a second back pressure. It communicates with the space (24). For this reason, compared with the case where the 2nd back pressure space (24) is not connected with the 1st space (16), the fluctuation of the pressure of the 2nd back pressure space (24) becomes gentle. Therefore, according to this embodiment, the fluctuation of the pressure in the second back pressure space (24) can be moderated, and the fluctuation range of the magnitude of the pressing force acting on the movable scroll (5) can be suppressed. . As a result, the inclination of the movable scroll (5) can be suppressed, and the efficiency and reliability of the scroll compressor (1) can be improved.

-Modification 1 of Embodiment 1-
In the scroll compressor (1) of the present embodiment, the lead-out groove (95) provided in the compression mechanism (14) may have a shape other than the U-shape shown in FIG.

  For example, the lead-out groove (95) may be formed in an annular shape as shown in FIG. The annular lead-out groove (95) surrounds the open end (91) of the high-pressure passage (90) in the fixed-side sliding contact surface (84) over the entire circumference. Further, a part of the annular lead-out groove (95) is located inside the circle Q in the figure, and the remaining part is located outside the circle Q. The circle Q shown in FIG. 7 is the same as the circle Q shown in FIG. Therefore, in the annular lead-out groove (95) shown in FIG. 7, the portion located inside the circle Q always faces the movable sliding surface (85), and the portion located outside the circle Q is the second. It is exposed intermittently to the back pressure space (24).

  Further, the lead-out groove (95) may be formed in a V shape as shown in FIG. The bent portion of the V-shaped lead-out groove (95) is located inside the open end (91) of the high-pressure passage (90) in the fixed side sliding contact surface (84). It extends toward the outer peripheral side of the wall (43). The V-shaped lead-out groove (95) has one end located outside the circle Q shown in FIG. A circle Q shown in FIG. 8 is the same as the circle Q shown in FIG. Therefore, in the V-shaped lead-out groove (95) shown in FIG. 8, the portion located inside the circle Q always faces the movable sliding contact surface (85), and the portion located outside the circle Q is the first. 2 Intermittent exposure to the back pressure space (24).

-Modification 2 of Embodiment 1
The compression mechanism (14) of this embodiment may be provided with a plurality of high-pressure passages (90) and a plurality of outlet grooves (95).

  In the fixed scroll (4) shown in FIG. 9, two high-pressure passages (90) are provided in the outer peripheral wall (43). Therefore, two open ends (91) of the high-pressure passage (90) are formed on the fixed side sliding contact surface (84) of the fixed scroll (4). Further, on the fixed side sliding contact surface (84), one lead-out groove (95) is formed corresponding to the open end (91) of each high-pressure passage (90). That is, the fixed scroll (4) shown in the figure is provided with two high-pressure passages (90) and two guide grooves (95).

  In the fixed-side sliding contact surface (84) of the fixed scroll (4) shown in FIG. 9, the open ends (91) of the two high-pressure passages (90) are opposite to each other across the fixed-side wrap (42). Has been placed. Further, the lead-out groove (95) corresponding to the open end (91) of each high-pressure passage (90) is formed in an annular shape similar to the lead-out groove (95) shown in FIG. That is, each lead-out groove (95) surrounds the open end (91) of the corresponding high-pressure passage (90) over the entire circumference. Further, a part of each lead-out groove (95) is located inside the circle Q in FIG. 9 and the remaining part is located outside the circle Q. A circle Q shown in FIG. 9 is the same as the circle Q shown in FIG.

-Modification 3 of Embodiment 1-
In the compression mechanism (14) of the present embodiment, the outlet groove (95) may always communicate with the second back pressure space (24).

  FIG. 10 shows the modification applied to the compression mechanism (14) shown in FIG. The lead-out groove (95) of the compression mechanism (14) shown in FIG. 2 is formed in a U shape (see FIG. 5). And the derivation | leading-out groove | channel (95) of this modification shown in FIG. 10 is extended in the outer peripheral side of the outer peripheral wall part (43) rather than the derivation | leading-out groove | channel (95) shown in FIG. Then, both end portions of the lead-out groove (95) of this modification are always exposed to the second back pressure space (24) regardless of the position of the movable scroll (5).

<< Embodiment 2 of the Invention >>
A second embodiment of the present invention will be described. The scroll compressor (1) of the present embodiment is obtained by changing the configuration of the compression mechanism (14) in the scroll compressor (1) of the first embodiment. Here, a different point from Embodiment 1 is demonstrated about the scroll compressor (1) of this embodiment.

  As shown in FIG. 11, in the compression mechanism (14) of the present embodiment, the high-pressure passage (90) and the lead-out groove (95) are provided in the movable scroll (5) instead of the fixed scroll (4).

  The high-pressure passage (90) of the present embodiment is formed in the movable side end plate portion (51) of the movable scroll (5). One end of the high-pressure passage (90) is an open end (91) that opens to the movable-side sliding contact surface (85). The open end (91) of the high-pressure passage (90) is disposed at a portion of the movable side sliding contact surface (85) that always faces the fixed side sliding contact surface (84). On the other hand, the other end of the high pressure passage (90) communicates with the boss internal space (58) which is a high pressure space.

  As shown in FIG. 12, the lead-out groove (95) of the present embodiment is a concave groove formed on the movable side sliding contact surface (85) of the movable scroll (5). The lead-out groove (95) is formed in a U shape surrounding the compression chamber (50) side of the open end (91) of the high-pressure passage (90). Further, both ends of the U-shaped lead-out groove (95) are open to the outer peripheral surface (56) of the movable side end plate portion (51). For this reason, both ends of the lead-out groove (95) are always in communication with the second back pressure space (24). Thus, the lead-out groove (95) of the present embodiment is formed so as to cross between the open end (91) of the high-pressure passage (90) and the compression chamber (50), and the second back pressure space (24). It is possible to communicate with.

  Similarly to the compression mechanism (14) of the first embodiment, in the compression mechanism (14) of the present embodiment, in the normal state where the movable scroll (5) is pressed against the fixed scroll (4), the fixed-side end plate portion (41 ) And the movable end plate portion (51) are sealed by an oil film (81), and the open end (91) of the high-pressure passage (90) is closed. Accordingly, in this state, the high-pressure lubricating oil in the boss inner space (58) does not flow out from the open end (91) of the high-pressure passage (90).

  On the other hand, if the pressing force acting on the movable scroll (5) is insufficient and the movable scroll (5) is tilted and overturned, the sealing effect by the oil film (81) is lost, and the high-pressure lubrication of the boss inner space (58) is lost. Oil flows out from the open end (91) of the high pressure passage (90). When the high-pressure lubricant flows into the second back pressure space (24), the pressure in the second back pressure space (24) increases. Further, when the high-pressure lubricating oil flows into the intermediate pressure second back pressure space (24), the refrigerant dissolved in the lubricating oil is gasified. Therefore, the pressure in the second back pressure space (24) also increases when the refrigerant in the lubricating oil is gasified. When the pressure in the second back pressure space (24) increases, the pressing force acting on the movable scroll (5) increases, and the tilt of the movable scroll (5) is eliminated.

  Here, when the lubricating oil flowing out from the open end (91) of the high pressure passage (90) flows into the compression chamber (50), only the volume of the flowing lubricating oil is sucked into the compression chamber (50). Refrigerant volume decreases. Further, when the high-pressure lubricating oil flowing out from the high-pressure passage (90) flows into the compression chamber (50) having a relatively low pressure, the refrigerant dissolved in the lubricating oil is gasified. Accordingly, when the lubricating oil flowing out from the high pressure passage (90) flows into the compression chamber (50), the efficiency of the scroll compressor (1) is lowered.

  Part of the lubricating oil present in the compression chamber (50) is discharged from the compression chamber (50) together with the high-pressure gas refrigerant, and flows out of the casing (10) from the discharge pipe (19). For this reason, when the lubricating oil flowing out from the high-pressure passage (90) flows into the compression chamber (50), the amount of lubricating oil flowing out to the outside of the casing (10) increases and is stored in the oil reservoir (15). There is a risk that the amount of lubricating oil will decrease, resulting in poor lubrication.

  On the other hand, in the compression mechanism (14) of the present embodiment, the lead-out groove (95) is formed on the movable sliding surface (85) of the movable end plate portion (51). And most of the lubricating oil flowing out from the open end (91) of the high-pressure passage (90) and flowing toward the compression chamber (50) flows into the outlet groove (95) and enters the second back pressure space (95). Led to 24). Therefore, according to the present embodiment, even when high-pressure lubricating oil flows out from the open end (91) of the high-pressure passage (90) in the overturned state, the amount of high-pressure lubricating oil flowing into the compression chamber (50) is reduced. Can be suppressed.

-Modification 1 of Embodiment 2
In the scroll compressor (1) of the present embodiment, the lead-out groove (95) provided in the compression mechanism (14) may have a shape other than the U-shape shown in FIG.

  For example, the lead-out groove (95) may be formed in a V shape as shown in FIG. The bent portion of the V-shaped lead-out groove (95) is located inside the opening end (91) of the high-pressure passage (90) in the movable sliding contact surface (85), and is movable from the bent portion. It extends toward the outer peripheral side of the side end plate portion (51). One end of the V-shaped lead-out groove (95) opens to the outer peripheral surface (56) of the movable side end plate portion (51). Therefore, the V-shaped lead-out groove (95) shown in FIG. 13 always communicates with the second back pressure space (24).

-Modification 2 of Embodiment 2
The compression mechanism (14) of this embodiment may be provided with a plurality of high-pressure passages (90) and a plurality of outlet grooves (95).

  In the movable scroll (5) shown in FIG. 14, two high-pressure passages (90) are provided in the movable side end plate portion (51). Accordingly, two open ends (91) of the high-pressure passage (90) are formed on the movable side sliding contact surface (85) of the movable scroll (5). Further, one lead-out groove (95) is formed on the movable side sliding contact surface (85) corresponding to the open end (91) of each high-pressure passage (90). In other words, the movable scroll (5) shown in the figure is provided with two high-pressure passages (90) and two guide grooves (95).

  On the movable side sliding contact surface (85) of the movable scroll (5) shown in FIG. 14, the open ends (91) of the two high-pressure passages (90) are opposite to each other across the movable side wrap (52). Has been placed. Further, the lead-out groove (95) corresponding to the open end (91) of each high-pressure passage (90) is formed in a U-shape similar to the lead-out groove (95) shown in FIG. That is, each lead-out groove (95) surrounds the compression chamber (50) side of the open end (91) of the corresponding high-pressure passage (90). Further, both ends of each lead-out groove (95) are open to the outer peripheral surface (56) of the movable side end plate portion (51).

<< Embodiment 3 of the Invention >>
Embodiment 3 of the present invention will be described. The scroll compressor (1) of the present embodiment is obtained by changing the configuration of the compression mechanism (14) in the scroll compressor (1) of the first embodiment. Here, a different point from Embodiment 1 is demonstrated about the scroll compressor (1) of this embodiment.

  As shown in FIG. 15, in the compression mechanism (14) of this embodiment, the lead-out groove (95) is provided not on the fixed scroll (4) but on the movable scroll (5). Note that the high-pressure passage (90) of the present embodiment is provided in the fixed scroll (4) as in the first embodiment.

  As shown in FIG. 16, the lead-out groove (95) of the present embodiment is formed on the movable side sliding contact surface (85) of the movable scroll (5). The lead-out groove (95) is formed in a U shape whose both ends open to the outer peripheral surface (56) of the movable side end plate portion (51).

  In the compression mechanism (14) of the present embodiment, when the movable scroll (5) performs a revolving motion, the fixed sliding surface (84) with respect to the lead-out groove (95) provided in the movable sliding surface (85). ) Changes the relative position of the open end (91) of the high-pressure passage (90). In the coordinates fixed to the movable scroll (5), the locus of the center of the open end (91) of the high-pressure passage (90) is a circle M shown in FIG. The radius of the circle M is equal to the amount of eccentricity r of the eccentric portion (72) with respect to the main shaft portion (71). In the lead-out groove (95) of the present embodiment, the opening end (91) of the high-pressure passage (90) is always more movable than the lead-out groove (95) even when the movable scroll (5) undergoes revolving motion ( 51) is located on the outer peripheral side.

  Similarly to the first embodiment, in the compression mechanism (14) of the present embodiment, when the movable scroll (5) is tilted and overturned, the second back pressure space (24) is opened from the open end (91) of the high-pressure passage (90). A high-pressure gas refrigerant is supplied. Further, most of the high-pressure gas refrigerant flowing out from the open end (91) of the high-pressure passage (90) and going to the compression chamber (50) flows into the outlet groove (95) and enters the second back pressure space (24 ).

<< Embodiment 4 of the Invention >>
Embodiment 4 of the present invention will be described. The scroll compressor (1) of the present embodiment is obtained by changing the configuration of the compression mechanism (14) in the scroll compressor (1) of the second embodiment. Here, a different point from Embodiment 2 is demonstrated about the scroll compressor (1) of this embodiment.

  As shown in FIG. 17, in the compression mechanism (14) of the present embodiment, the lead-out groove (95) is provided not in the movable scroll (5) but in the fixed scroll (4). Note that the high-pressure passage (90) of the present embodiment is provided in the movable scroll (5) as in the second embodiment.

  As shown in FIG. 18, the lead-out groove (95) of the present embodiment is formed on the fixed side sliding contact surface (84) of the fixed scroll (4). The lead-out groove (95) is U-shaped, and both ends thereof are located outside the circle Q in the figure. The circle Q in FIG. 18 is the same as the circle Q in FIG. Therefore, both end portions of the U-shaped lead-out groove (95) are intermittently exposed to the second back pressure space (24).

  In the compression mechanism (14) of the present embodiment, when the movable scroll (5) performs a revolving motion, the movable side sliding contact surface (85) with respect to the lead-out groove (95) provided on the fixed side sliding contact surface (84). ) Changes the relative position of the open end (91) of the high-pressure passage (90). The locus of the center of the open end (91) of the high-pressure passage (90) provided in the movable scroll (5) is a circle N shown in FIG. The radius of the circle N is equal to the amount of eccentricity r of the eccentric portion (72) with respect to the main shaft portion (71). The lead-out groove (95) of the present embodiment is such that the lead-out groove (95) is located between the open end (91) of the high-pressure passage (90) and the compression chamber (50) even if the orbiting scroll (5) revolves. It is the shape which is located in.

  Similarly to the second embodiment, in the compression mechanism (14) of the present embodiment, when the movable scroll (5) is tilted and overturned, the second back pressure space (24 ) Is supplied with high-pressure lubricant. Further, most of the high-pressure lubricating oil that flows out from the open end (91) of the high-pressure passage (90) and travels toward the compression chamber (50) flows into the outlet groove (95) and enters the second back pressure space (95). Led to 24).

  In addition, said embodiment and modification are essentially preferable illustrations, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a scroll compressor that presses the movable scroll against the fixed scroll by applying an intermediate pressure to the back surface of the movable scroll.

1 Scroll compressor
10 Casing
14 Compression mechanism
16 Upper space (first)
17 Lower space (second space)
24 Second back pressure space (intermediate pressure)
3 Housing
4 Fixed scroll
42 Fixed side wrap (wrap)
45 High pressure chamber (high pressure space)
48 Intermediate pressure passage
5 Moveable scroll
50 compression chamber
51 Movable end panel
52 Movable wrap (wrap)
56 Outer peripheral surface (of movable end plate)
57 Back (of movable side panel)
58 Inside the boss (high pressure space)
6 Electric motor
84 Fixed sliding surface
85 Movable sliding surface
90 High pressure passage
95 Lead groove (lead recess)

Claims (7)

The fixed scroll (4) and the movable scroll (5) each provided with a spiral wrap (42, 52) are provided, and the wrap (42, 52) of the fixed scroll (4) and the movable scroll (5). A compression mechanism (14) that meshes with each other to form a compression chamber (50);
A casing (10) for accommodating the compression mechanism (14),
The compression mechanism (14) is a scroll compressor that sucks and compresses low-pressure fluid into the compression chamber (50), and discharges the compressed high-pressure fluid from the compression chamber (50).
The movable scroll (5) includes a movable side end plate portion (51) from which the wrap (52) protrudes from the front surface.
The front surface of the movable side end plate part (51) has a movable side sliding contact surface (85) in which a portion surrounding the periphery of the wrap (52) is in sliding contact with the fixed side sliding contact surface (84) of the fixed scroll (4). While
The compression mechanism (14)
An intermediate pressure space (24) facing the outer peripheral surface (56) and the rear surface (57) of the movable side end plate portion (51) of the movable scroll (5);
An intermediate pressure passage (48) for communicating the compression chamber (50) in the middle of compression with the intermediate pressure space (24);
A high pressure space (45,58) in which the internal pressure becomes the pressure of the high pressure fluid,
A high pressure passage (90) having one end opened to one of the fixed side sliding contact surface (84) and the movable side sliding contact surface (85) and the other end communicating with the high pressure space (45, 58). A scroll compressor characterized by comprising. In claim 1,
One of the fixed side sliding contact surface (84) and the movable side sliding contact surface (85) has the high pressure opening to the fixed side sliding contact surface (84) or the movable side sliding contact surface (85). A lead-out recess (95) formed so as to cross between an end of the passage (90) and the compression chamber (50) and capable of communicating with the intermediate pressure space (24) is provided. Scroll compressor. In claim 2,
The scroll compressor characterized in that the lead-out recess (95) is always in communication with the intermediate pressure space (24). In any one of Claims 1 thru | or 3,
The scroll compressor according to claim 1, wherein the high-pressure space (45) is a space from which the compressed high-pressure fluid is discharged from the compression chamber (50). In any one of Claims 1 thru | or 3,
The scroll compressor, wherein the high-pressure passage (90) is provided in the fixed scroll (4) and is open to the fixed-side sliding contact surface (84). In any one of Claims 1 thru | or 3,
The scroll compressor characterized in that the high-pressure passage (90) is provided in the movable scroll (5) and opens to the movable-side sliding contact surface (85). In any one of Claims 1 thru | or 6,
While comprising an electric motor (6) housed in the casing (10) and driving the compression mechanism (14),
The compression mechanism (14) is disposed on the back side of the movable scroll (5), and the space in the casing (10) is separated from the first space (16) on the compression mechanism (14) side and the electric motor (6). A housing (3) that partitions into the second space (17) on the side,
The scroll compressor characterized in that the first space (16) communicates with the intermediate pressure space (24).

Images