JP2007100602A - Gas compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent vanes from chattering while suppressing an increase in power loss in a gas compressor. <P>SOLUTION: The biasing force P3 of a spring 39 is set so that when an internal pressure in the compression chamber 48 of a compressor body is lower than a predetermined reference pressure set beforehand, a valve 38 installed in a front side block 30 is displaced to an intermediate pressure detection hole 36a side communicating with a countersunk groove 35 from a low pressure detection hole 36b side communicating with a suction chamber. A high-pressure supply passage 32a is communicated with a large diameter part 32c through a clearance formed between the thin-walled part 38c and the sliding passage 32b of the valve 38, by the displacement of the valve 38 to communicate the high-pressure supply passage 32a, the clearance (sliding passage 32b), the large diameter part 32c, and the high-pressure supply passage 37 with each other. A high-pressure Pd refrigerator oil R fed to an oil passage 33 is fed to the rear pressure chambers 59 for the vanes 58 to increase the projection force of the vanes 58 for the prevention of chattering. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a gas compressor, and in particular, to an improvement in a hydraulic pressure supply passage through which a vane forming a compression chamber projects.

  Conventionally, in an air conditioning system (hereinafter referred to as an air conditioning system), a gas compressor (compressor) for compressing refrigerant gas and circulating the refrigerant gas in the system is used.

  For example, in a general compressor provided with a vane rotary type compressor main body inside a housing, the compressor main body includes a substantially cylindrical rotor that rotates integrally with the rotary shaft and a circle of the rotor. Two side blocks (front side block, rear side) that are arranged so as to sandwich the cylinder and the rotor and cylinder from both ends of the cylinder that surround the outside of the columnar outer peripheral surface and have an inner peripheral surface with a substantially elliptical cross-sectional profile For example, five blocks are arranged at predetermined angular intervals in the circumferential direction of the rotor, and can be protruded from the outer peripheral surface of the rotor by hydraulic pressure, and the tip portion in the protruding state abuts on the substantially elliptical inner peripheral surface of the cylinder. A vane, and by rotation about the axis of the rotor, the rotor, the cylinder, both side blocks, and two adjacent vanes in the direction of rotation are separated. Is five, respectively by changing the respective volumes of the compression chambers and is configured to compress the refrigerant gas inside each compression chamber.

  The compressor main body is covered with a housing in which a discharge port for discharging high-pressure refrigerant gas protruding from the compressor main body to the air conditioning system and a suction port for sucking low-pressure refrigerant gas from the air conditioning system are formed. In the space formed between the housing and the compressor body, the front side block side leading to the suction port across the compressor body has a low-pressure atmosphere into which refrigerant gas introduced into the compression chamber flows. The rear side block side that is formed as a suction chamber and communicates with the discharge port is formed as a discharge chamber in a high-pressure atmosphere into which refrigerant gas discharged from the compression chamber flows.

  Here, the compressor is mainly filled with refrigerating machine oil as the above-described operating oil of the vane and as lubricating oil for the purpose of reducing friction, cooling, cleaning (removing abrasion powder, etc.) of the movable part. And is stored at the bottom of the discharge chamber in a high-pressure atmosphere.

  The above-described vane of the compressor main body is disposed in a vane groove formed in the rotor so as to protrude outward, and a space between the bottom of the vane groove and the bottom surface of the vane (back pressure space, back pressure). When the refrigeration oil as the working oil is supplied to the chamber), the vane protrudes toward the cylinder.

  The supply passage for the refrigerating machine oil to the back pressure space is formed as follows. That is, the rear side block that partitions the discharge chamber is formed with a supply passage that communicates from a portion immersed in the refrigerating machine oil accumulated at the bottom of the discharge chamber to a bearing hole that supports the rotating shaft. Due to the high pressure atmosphere, the bearing hole is reached from the lower opening of the supply passage in the rear side block through the supply passage.

  Then, the high-pressure refrigerating machine oil that has reached the bearing hole passes through a slight gap between the bearing hole and the outer peripheral surface of the rotating shaft, and reaches between the end surfaces of the rear side block and the rotor. At this time, the pressure of the refrigerating machine oil is reduced to an intermediate pressure due to a pressure loss while passing through a slight gap.

  Furthermore, a shallow depression (saray groove) is formed in a portion of the end face of the rear side block facing the rotor, facing the bottom of the vane groove in the rotating rotor, and between the end faces of the rear side block and the rotor. The refrigerating machine oil that has reached is supplied to the back pressure space of the vane groove through this Saray groove, and causes the vane to protrude.

  Further, the supply passage for the refrigerating machine oil to the back pressure space is formed not only on the rear side block side described above but also on the front side block side.

That is, the other supply passage extends from the lower part of the rear side block facing the discharge chamber to the lower part of the front side block through the peripheral wall of the cylinder, and further from the lower part of the front side block to a bearing which is a bearing part of the rotating shaft. Refrigerating machine oil reaches the Saray groove of the front side block formed in the same way as the rear side block side from the discharge chamber, through the supply passages of the rear side block, cylinder, and front side block. Then, it is supplied to the back pressure space of the vane groove through this Saray groove, and the vane is protruded (Patent Document 1, etc.).
JP 2004-360491 A (FIG. 1 etc.)

  By the way, the above-described compressor has a low compression ratio condition, that is, a condition when the pressure ratio value Pd / Ps between the discharge gas pressure (high pressure) Pd and the suction gas pressure (low pressure) Ps becomes small. This is the case in an operating condition under a low load condition. Under this condition, the compression timing with respect to the volume change becomes earlier, and the pressing load acting on the vane tip from the cylinder inner peripheral surface rises from the earlier timing. The balance between the load and the hydraulic pressure in the back pressure space acting in the direction of pushing up the vane becomes unstable, and vane chattering is likely to occur. As a result, the operating noise increases, and the sealing performance of the compression chamber is reduced, leading to a reduction in compression efficiency.

  On the other hand, in the compression stroke, in order to prevent the pressure balance described above from becoming unstable by applying a hydraulic pressure higher than the pressure in the Sarai groove to the back pressure space, However, if the pressure applied to the back pressure space is increased, the frictional force between the tip of the vane and the inner peripheral surface of the cylinder increases, resulting in power loss. It is relatively large and disadvantageous.

  This invention is made | formed in view of the said situation, Comprising: It aims at providing the gas compressor which can prevent chattering of a vane, suppressing that a power loss increases.

  The gas compressor according to the present invention is different from the existing supply passage (intermediate pressure supply passage) when the vane chattering is likely to occur, that is, when the pressure in the compression chamber is lower than a predetermined reference pressure. From the supply passage (high pressure supply passage), apply a higher hydraulic pressure to the vane back pressure, otherwise do not apply a high pressure to reduce power loss (situation where high pressure is applied). This is a balance between the prevention of chattering and the suppression of power loss.

  That is, the gas compressor according to claim 1 of the present invention is a compressor body having a rotating body that rotates around a rotation axis, and surrounds a substantially cylindrical rotor and an outer peripheral surface of the rotor from the outside. A plurality of cylinders having a substantially elliptical cross-sectional profile, two side blocks arranged so as to sandwich the rotor and the cylinder from both end face sides, and a plurality of predetermined angular intervals in the circumferential direction of the rotor. A vane that can freely protrude from the outer peripheral surface of the rotor by a predetermined hydraulic pressure, and a tip portion in a protruding state is in contact with the substantially elliptical inner peripheral surface of the cylinder, and by rotation of the rotor, A gas compressor that compresses the gas inside the compression chamber by changing the volumes of a plurality of compression chambers defined by the cylinder, the side blocks, and the vanes. In addition to the predetermined hydraulic pressure supply path (existing intermediate pressure supply path) to the vane, the hydraulic pressure higher than the predetermined hydraulic pressure is applied to the vane when the compression chamber is in the compression stroke. A high pressure supply passage is formed, and when the internal pressure of the compression chamber in the compression stroke is lower than a predetermined reference pressure, the high pressure hydraulic pressure is supplied to the high pressure supply passage. A valve for opening and closing the high pressure supply passage is disposed so that the high pressure oil pressure is not supplied to the high pressure supply passage when the internal pressure in the compression stroke is higher than the reference pressure. To do.

  According to the gas compressor according to claim 1 of the present invention configured as described above, when the internal pressure of the compression chamber in the compression stroke is lower than a predetermined reference pressure (when chattering is likely to occur), An on-off valve arranged in a high pressure supply passage that is provided separately from the intermediate pressure supply passage applies a hydraulic pressure higher than the intermediate pressure to the back pressure of the vane. The balance between the applied pressing load and the load acting in the direction of pushing up the vane (hydraulic pressure in the back pressure space) can be stabilized, and chattering of the vane can be prevented.

  On the other hand, when the internal pressure of the compression chamber in the compression stroke is higher than a predetermined reference pressure (when chattering is difficult to occur), the on-off valve arranged in the high-pressure supply passage is used for the back pressure of the vane than the intermediate pressure. Since no high-pressure oil pressure is applied, only the intermediate-pressure oil pressure from the existing intermediate-pressure supply passage acts as the vane back pressure, so there is friction between the tip of the vane and the inner peripheral surface of the cylinder. An unnecessary increase in force can be prevented, and an increase in power loss due to an increase in frictional force can be suppressed.

  The gas compressor according to claim 2 of the present invention is the gas compressor according to claim 1, wherein the high-pressure supply passage is formed in the side block and defines a compression chamber when in the compression stroke. An intermediate pressure detection hole communicating with a hydraulic oil passage loaded on the vane, and a low pressure detection hole communicating with a low pressure atmosphere corresponding to the internal pressure of the compression chamber during the intake stroke, wherein the valve detects the intermediate pressure A hydraulic pressure higher than the predetermined hydraulic pressure is supplied to the high pressure supply passage in accordance with a differential pressure between the hole and the low pressure detection hole.

  According to the gas compressor according to claim 2 of the present invention configured as described above, the pressure of the medium pressure detection hole and the pressure of the low pressure detection hole communicated with the hydraulic oil passage loaded on the vane defining the compression chamber. By operating the valve with a pressure difference from the pressure, it can be alternatively detected that the internal pressure in the compression chamber is lower than a predetermined reference pressure. Therefore, the operation of detecting the internal pressure in the compression chamber and the operation of supplying the high-pressure hydraulic pressure to the high-pressure supply passage can be performed simultaneously, thereby simplifying the configuration. Can be achieved.

  Here, in accordance with the differential pressure between the medium pressure detection hole and the low pressure detection hole, only the differential pressure ΔP (= P1−P2) between the oil pressure P1 at the medium pressure detection hole and the oil pressure P2 at the low pressure detection hole. For example, when the valve is biased by a spring or an elastic body for biasing the valve to a position where high pressure oil pressure is not supplied, the oil pressure P1 in the medium pressure detection hole and the low pressure detection hole And depending on the pressure difference ΔP (= P1− (P2 + P3)) between the hydraulic pressure P2 and the biasing force P3 such as a spring against the valve.

  In addition, since the elastic force by a spring or the like normally follows Hooke's law, the urging force (the restoring force of the spring or elastic body) varies according to the displacement (the length of expansion / contraction from the natural length).

  A gas compressor according to a third aspect of the present invention is the gas compressor according to the second aspect, wherein the gas compressor covers the outside of the main body of the compressor and discharges the gas to the outside through which the gas is sucked from the outside. A housing in which a port is formed, and communicates with the suction port, a suction chamber into which the gas sucked into the compressor body is introduced, and communicates with the discharge port so that gas flows from the compressor body. A discharge chamber to be discharged is formed across the compressor body along the axial direction of the rotary shaft, the high pressure oil pressure is a pressure by oil stored in the discharge chamber, and the low pressure atmosphere is the suction chamber It is characterized by being.

  According to the gas compressor according to claim 3 of the present invention configured as described above, the high pressure supply passage is formed inside the partition wall of the compressor body that partitions the compression chamber and the suction chamber, and the medium pressure detection hole is formed. In addition, a low-pressure detection hole and a valve can be provided, and the structure can be simplified.

  Moreover, as the high pressure hydraulic pressure supplied to the high pressure supply passage, the pressure by the lubricating oil (refrigeration machine oil) stored in the discharge chamber can be used, so there is no need to separately prepare the high pressure hydraulic pressure. The structure can be simplified.

  In each gas compressor according to the present invention described above, as a gas to be compressed, for example, a refrigerant gas such as chlorofluorocarbon gas or carbon dioxide gas can be applied, but the gas is not limited to these refrigerant gases. Absent.

  The low pressure atmosphere may be a space having a pressure lower than the pressure of the compressed gas in the space portion corresponding to the compression stroke in the internal space surrounded by the cylinder, in addition to the suction chamber described above.

  The compressor main body may be of a scroll type including a vane rotary type or a swash plate reciprocating type.

  According to the gas compressor of the present invention, when the internal pressure of the compression chamber in the compression stroke is lower than a predetermined reference pressure (when chattering is likely to occur), the pressing load acting on the vane tip from the cylinder inner peripheral surface And the load acting in the direction of pushing up the vane (the hydraulic pressure in the back pressure space) can be stabilized, and chattering of the vane can be prevented.

  On the other hand, when the internal pressure of the compression chamber in the compression stroke is higher than a predetermined reference pressure (when chattering is difficult to occur), the frictional force between the tip of the vane and the inner peripheral surface of the cylinder is increased unnecessarily. Can be prevented, and an increase in power loss due to an increase in frictional force can be suppressed.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best embodiment of the gas compressor of the invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing a vane rotary compressor 100 which is an embodiment of a gas compressor according to the present invention, and FIG. 2 shows a cross section (excluding the case 11) along the line AA in FIG. 3 is a view of the front side block 30 in FIG. 1 as viewed from the same direction as FIG. 1 corresponds to a cross-sectional view taken along line BB in FIG.

  The compressor 100 is configured, for example, as a part of a GHP (gas heat pump) air conditioning system (hereinafter simply referred to as an air conditioning system) that performs cooling using the heat of vaporization of a cooling medium. Along with the condenser, expansion valve, evaporator, and the like (all of which are not shown) as components, they are provided on the cooling medium circulation path.

  The compressor 100 compresses a gaseous cooling medium taken from the evaporator of the air conditioning system, that is, the refrigerant gas G, and supplies the compressed refrigerant gas G to the condenser of the air conditioning system. The condenser liquefies the compressed refrigerant gas G and sends it to the expansion valve as a high-pressure liquid refrigerant (liquid).

  The high-pressure liquid refrigerant is reduced in pressure by the expansion valve and sent to the evaporator. The low-pressure liquid refrigerant absorbs heat from ambient air and vaporizes in the evaporator, and cools the air around the evaporator by heat exchange with the heat of vaporization.

  The compressor 100 includes a compressor main body housed in a housing including a case 11 and a front head 12, and a transmission mechanism that is attached to the front head 12 and transmits a driving force from a driving source (not shown) to the compressor main body. 13. The transmission mechanism 13 is rotatably supported by a radial ball bearing 14 with respect to the front head 12.

  The case 11 has a cylindrical body that is open at one end, and the front head 12 is assembled so as to cover the opened part of the case 11. The front head 12 is formed with a suction port 12a through which a low-pressure refrigerant gas G is sucked from the evaporator, and a check valve 12b for preventing the refrigerant gas G from flowing backward is provided at the suction port 12a. . On the other hand, the case 11 is formed with a discharge port 11a for discharging the high-pressure refrigerant gas G compressed by the compressor body to the condenser.

  The compressor main body accommodated in the housing includes a rotating shaft 51 that is driven to rotate about the axis by the transmission mechanism 13, a rotor 50 that rotates integrally with the rotating shaft 51, and an outer peripheral surface of the rotor 50. The cylinder 40 which has an inner peripheral surface 49a (see FIG. 2) having a substantially oval cross-sectional contour and is open at both ends, and protrudes from the outer peripheral surface of the rotor 50, and the protruding tip is formed on the inner peripheral surface 49a of the cylinder 40. The five plate-like vanes 58 provided in the rotor 50 at equal angular intervals around the rotating shaft 51 and the front side block fixed so as to cover the open end surfaces from the outside of the open end surfaces on both sides of the cylinder 40. 30 and the rear side block 20.

  The compression chambers 48 defined by the two side blocks 20 and 30, the rotor 50, the cylinder 40, and the two vanes 58 and 58 that follow each other in the rotation direction of the rotor 50 (clockwise direction in FIG. 2). The volume of the refrigerant is repeatedly increased and decreased according to the rotation of the rotary shaft 51, whereby the refrigerant gas G sucked into each compression chamber 48 is compressed and discharged.

  One of the portions of the rotary shaft 51 protruding from both end surfaces of the rotor 50 is pivotally supported by the bearing portion 32 of the front side block 30 and extends outward through the front head 12. The penetrating portion is pivotally supported by the front head 12, and the portion extending outward is connected to the transmission mechanism 13. Similarly, the other side of the protruding portion of the rotating shaft 51 is pivotally supported by the bearing portion 22 of the rear side block 20.

  The compressor body is a housing by supporting the rotating shaft 51 by the front head 12 and holding the outer peripheral portions of the side blocks 20 and 30 on the inner peripheral surface of the case 11 and the front head 12 by O-rings or the like. Is held at a predetermined position.

  Further, the discharge chamber 21 is formed by the rear side block 20 and the case 11 in a state where the compressor main body is accommodated in the case 11, while the suction chamber 34 is formed by the front side block 30 and the front head 12. The discharge chamber 21 communicates with the discharge port 11a, and the suction chamber 34 communicates with the suction port 12a.

  The suction chamber 34 and the discharge chamber 21 are hermetically isolated by the above-described O-ring or the like. Further, a cyclone block 60 for separating the refrigerating machine oil R from the refrigerant gas G is attached to the rear side block 20, and the cyclone block 60 is exposed in the discharge chamber 21.

  Here, the mechanical seal 15 is disposed on the outer side of the portion of the rotary shaft 51 of the compressor main body that is supported by the bearing portion 32 of the front side block 30. The mechanical seal 15 is a member that prevents the refrigerating machine oil R from leaking outside the housing through the rotating shaft 51.

  The space 16 in which the mechanical seal 15 is disposed is formed by the outer surface of the front side block 30 and the inner surface of the front head 12, and the space 16 is formed by the communication path 12c formed in the front head 12. It communicates with the suction chamber 34. Therefore, the space 16 in which the mechanical seal 15 is disposed is a low-pressure space like the suction chamber 34.

  Further, in the lower part of the discharge chamber 21, a refrigerating machine oil that lubricates, cools, and cleans the sliding portion of the compressor 10 and applies pressure so that the vane 58 protrudes toward the inner peripheral surface 49 a of the cylinder 40. R is stored.

  That is, in the rotor 50, five slit-like vane grooves 56 are formed radially and at equiangular intervals around the rotation center of the rotor 50. The vanes 58 are inserted into the vane grooves 56, and The vane 58 is directed in the direction of the inner peripheral surface 49a of the cylinder 40 by the centrifugal force generated by the rotation of the rotor 50 and the hydraulic pressure of the refrigerating machine oil R applied to the back pressure chamber 59 defined by the vane groove 56 and the bottom surface of the vane 58. The tip of the vane 58 protruding is urged to abut against the inner peripheral surface 49a of the cylinder 40.

  Accordingly, each compression chamber 48 defined by the cylinder 40, the rotor 50, the two vanes 58 and 58 that are arranged in the rotational direction of the rotor 50, the front side block 30, and the rear side block 20 is The volume change is repeated according to 50 rotations.

  As shown in FIGS. 2 and 3, the front side block 30 has a front-side suction port 31 that allows the suction chamber 34 and the compression chamber 48 to communicate with each other, and is introduced into the suction chamber 34 from the suction port 12a. The refrigerant gas G is sucked into the compression chamber 48 through the front suction port 31.

  On the other hand, a recess is formed in a part of the outer periphery of the cylinder 40, and this recess forms a discharge chamber 44 surrounded by the inner end surfaces of the side blocks 20 and 30 and the inner peripheral surface of the case 11. .

  A discharge port 42 that allows the compression chamber 48 and the discharge chamber 44 to communicate with each other is formed in the thinned cylinder 40 where the discharge chamber 44 is formed, and the discharge port 42 is open to the discharge chamber 44 side. A reed valve 43 (a valve body and a valve support) is provided. The high-pressure refrigerant gas G discharged from the compression chamber 48 through the discharge port 42 and the reed valve 43 to the discharge chamber 44 is connected to a communication hole (not shown) formed in the rear side block 20 and the rear side block 20. The oil is discharged into the discharge chamber 21 through the oil separator 60a of the fixed cyclone block 60.

  On the other hand, the refrigerating machine oil R separated from the refrigerant gas G by the oil separator 60a is dropped onto the bottom of the discharge chamber 21, and is stored at the bottom as described above.

  Further, the compressor 100 includes lubrication between the rotary shaft 51 and the bearing portions 22 and 32, lubrication between the end surfaces of the rotor 50 and the inner end surfaces of the side blocks 20 and 30, and supply to the back pressure chamber 59. In order to supply the vane urging hydraulic pressure or the like, a structure is provided in which the refrigerating machine oil R stored in the lower part of the discharge chamber 21 is guided to each part.

  That is, an oil passage 23 reaching the bearing portion 22 is formed in the rear side block 20, and an inner end surface of the rear side block 20 is formed between the bearing portion 22 and the rotary shaft 51 from the opening of the oil passage 23 in the bearing portion 22. A recess (Saray groove) 25 communicating with the back pressure chamber 59 of the rotor 50 is formed through a minute gap therebetween.

  Further, a through hole 46 connected to the oil passage 23 of the rear side block 20 is provided at the bottom of the cylinder 40, and the opening on the front side block 30 side of the through hole 46 and the bearing portion 32 are communicated with the front side block 30. The oil passage 33 is formed so that the refrigerating machine oil R passes through a minute gap between the bearing portion 32 and the rotating shaft 51 and enters a recess (saray groove) 35 formed on the inner end surface of the front side block 30. Refrigerating machine oil R is guided.

  Here, the salai groove 35 of the front side block 30 also communicates with the back pressure chamber 59 of the rotor 50, similarly to the salai groove 25 of the rear side block 20, and the salai groove 25 of the rear side block 20 and the salai groove of the front side block 30. The basic configuration of the groove 35 such as the contour shape that appears in the form shown in FIG. 3 is substantially symmetric.

  The internal pressure of the discharge chamber 21 is increased by the high-pressure refrigerant gas G discharged from the compression chamber 48 during operation of the compressor 100, and the high pressure acts on the refrigerating machine oil R accumulated at the bottom. Yes.

  However, the refrigerating machine oil R supplied to the Sarai groove 25 through the oil passage 23 is accumulated at the bottom of the discharge chamber 21 due to a pressure loss when passing through a minute gap between the bearing portion 22 and the rotating shaft 51. The pressure (intermediate pressure Pv) is lower than the pressure at that time (high pressure Pd).

  That is, the Saray grooves 25 and 35 can be called intermediate pressure supply passages that apply the intermediate pressure Pv to the vanes 58.

  Of the annular saray groove 35 in a plan view of FIG. 3, an end surface portion other than the saray groove 35 is provided in a portion through which the back pressure chamber 59 of the vane 58 defining the compression chamber 48 positioned at the end of the compression stroke passes. Island-shaped portions 35a and 35a having substantially the same height are formed.

  The island portions 35a and 35a are formed with other oil passages 37 and 37, respectively, which are different from the Sarai groove 35 as the intermediate pressure supply passage described above. The oil passage 37 is referred to as a high-pressure supply passage (hereinafter referred to as a high-pressure supply passage 37) that supplies a refrigerating machine oil R having a hydraulic pressure (high pressure Pd) higher than the intermediate pressure Pv supplied to the Saray groove 35 to the back pressure chamber 59. ).

  Further, as shown in FIG. 4, the front side block 30 is provided with an intermediate pressure detection hole 36a that opens into the Saray groove 35 and detects the oil pressure of the Saray groove 35, and is connected to the communication path 12c. A low-pressure detection hole 36b communicating with the suction chamber 34 is formed.

  The medium pressure detection hole 36a and the low pressure detection hole 36b are opened toward each end face of the valve 38 in the sliding passage 32b of the valve 38 disposed in the front side block 30 (FIG. 4). reference). The valve 38 is formed in a substantially cylindrical shape with a constricted portion 38c having a smaller radius than both ends at the central portion, and is movable in the sliding passage 32b, but is pulled by a spring 39. Thus, it is biased toward the low pressure detection hole 36b.

  A high pressure supply passage 32 a communicating with the oil passage 33 is formed in a portion of the sliding passage 32 b corresponding to the constricted portion 38 c of the valve 38. The high-pressure supply passage 32a opens toward the constricted portion 38c regardless of the position of the valve 38 in the sliding passage 32b.

  Further, in the sliding passage 32b, a large-diameter portion 32c having a diameter larger than that of the other portion of the sliding passage 32b is formed between the end surface on the intermediate pressure detection hole 36a side and the high-pressure supply passage 32a. . The large diameter portion 32 c communicates with the high pressure supply passage 37.

  Here, when the valve 38 is urged toward the low-pressure detection hole 36b (FIG. 4A), the large-diameter portion 32c is blocked by a portion other than the constricted portion 38c of the valve 38. On the other hand, when the valve 38 is displaced toward the intermediate pressure detection hole 36a (FIG. 4B), a gap is formed between the constricted portion 38c of the valve 38 and the sliding passage 32b. The high pressure supply passage 32a and the large diameter portion 32c communicate with each other through the gap (sliding passage 32b).

  As a result, the high pressure supply passage 32a, the gap (sliding passage 32b), the large diameter portion 32c, and the high pressure supply passage 37 communicate with each other, and the high pressure Pd refrigerating machine oil R supplied to the oil passage 33 is supplied to the high pressure supply passage 32a. , The gap (sliding passage 32b), the large diameter portion 32c, and the high pressure supply passage 37 are supplied to the back pressure chamber 59 of the vane 58 that defines the compression chamber 48 located at the end of the compression stroke. Increase the impact power.

Here, when the pressure difference between the pressure P3 corresponding to the biasing force of the spring 39 and the low pressure Ps acting on the low pressure detection hole 36b and the intermediate pressure Pv acting on the intermediate pressure detection hole 36a is ΔP,
ΔP = Pv− (Ps + P3)
Therefore, when the differential pressure ΔP is positive (0 <ΔP), the valve 38 is displaced toward the low pressure detection hole 36b, and when the differential pressure ΔP is 0 or negative (ΔP ≦ 0), the valve 38 is medium pressure. Displacement toward the detection hole 36a.

  Therefore, when the valve 38 is displaced to the low pressure detection hole 36b side, the intermediate pressure Pv, which is the hydraulic pressure of the Sarai groove 35, acts on the back pressure chamber 59 of the vane 58, and the valve 38 is on the medium pressure detection hole 36a side. Is higher than the oil pressure of the Sarai groove 35, and the back pressure chamber 59 of the vane 58 that defines the compression chamber 48 located at the end of the compression stroke is acted on. An intermediate pressure Pv that is the hydraulic pressure of the Sarai groove 35 acts on the back pressure chamber 59.

  Therefore, the magnitude of the hydraulic pressure applied to the back pressure chamber 59 can be switched between the intermediate pressure Pv and the high pressure Pd, and the switching point (pressure) when switching the applied pressure is determined by the biasing force P3 of the spring 39. By setting a spring constant (longitudinal elastic modulus) that can be set, that is, to obtain the biasing force P3, the switching point can be arbitrarily set.

  Here, the high pressure Pd acting on the refrigerating machine oil R in the discharge chamber 21 is not always a constant high pressure, and similarly, the salai in which the oil pressure (high pressure Pd) of the refrigerating machine oil R in the discharge chamber 21 is reduced. The intermediate pressure Pv in the groove 35 is not constant.

  The pressure acting on the refrigerating machine oil R in the discharge chamber 21 is based on the discharge pressure of the refrigerant gas G discharged from the compression chamber 48 to the discharge chamber 21, and the so-called low compression ratio condition, that is, the discharge of the refrigerant gas G When the pressure ratio Pd / Ps between the pressure (high pressure) Pd and the suction pressure (low pressure) Ps of the refrigerant gas G becomes small, the compression timing with respect to the volume change becomes earlier, and the vane 58 reaches the vane 58 from the inner peripheral surface 49a of the cylinder 40. The pressing load acting on the tip rises from an early timing, and with the conventional compressor 100, the balance between the pressing load and the hydraulic pressure of the back pressure chamber 59 acting in the direction of pushing up the vane 58 becomes unstable. Chattering of the vane 58 is likely to occur, resulting in an increase in operating noise and a decrease in compression efficiency due to a decrease in the sealing performance of the compression chamber 48.

  However, in the compressor 100 according to the present embodiment, the valve 38 is in a low compression ratio condition where the chattering of the vane 58 is likely to occur, that is, when the internal pressure of the compression chamber 48 is lower than a predetermined reference pressure. The biasing force P3 of the spring 39 is set so as to be displaced toward the intermediate pressure detection hole 36a.

  As a result, in a normal operation state in which chattering of the vane 58 is not likely to occur, the differential pressure ΔP becomes positive (0 <ΔP), and the valve 38 remains biased toward the low pressure detection hole 36b. The intermediate pressure Pv, which is the hydraulic pressure of the Sarai groove 35, acts on the back pressure chamber 59.

  Under this condition, the projecting output of the vane 58 due to the intermediate pressure Pv is sufficient to prevent chattering, and the frictional force between the tip of the vane 58 and the inner peripheral surface 49a of the cylinder 40 is not increased.

  On the other hand, in an operation state in which chattering of the vane 58 is likely to occur, the differential pressure ΔP is negative (ΔP ≦ 0), and the valve 38 is displaced toward the intermediate pressure detection hole 36a.

  When the valve 38 is displaced toward the intermediate pressure detection hole 36a (FIG. 4B), a gap is formed between the constricted portion 38c of the valve 38 and the peripheral surface of the sliding passage 32b. The high pressure supply passage 32a and the large diameter portion 32c communicate with each other through the gap (sliding passage 32b), and the high pressure supply passage 32a, the gap (sliding passage 32b), the large diameter portion 32c, and the high pressure supply passage 37 communicate with each other. The refrigerating machine oil R of high pressure Pd supplied to the oil passage 33 is located at the end of the compression stroke through the high pressure supply passage 32a, the gap (sliding passage 32b), the large diameter portion 32c and the high pressure supply passage 37. This is supplied to the back pressure chamber 59 of the vane 58 that defines the compression chamber 48 to increase the thrust output of the vane 58.

  This stabilizes the balance between the pressing load acting on the tip of the vane 58 from the inner peripheral surface 49a of the cylinder 40 and the load acting in the direction of pushing up the vane 58 (pressure Pd acting on the back pressure chamber 59). And chattering of the vane 58 can be prevented.

  At this time, the frictional force between the tip of the vane 58 and the inner peripheral surface 49a of the cylinder 40 increases as the projecting output of the vane 58 increases, but when the situation in which chattering of the vane 58 is likely to occur is eliminated, that is, When the operating condition under the low compression ratio condition is eliminated, the differential pressure ΔP becomes positive (0 <ΔP), the valve 38 is returned to the low pressure detection hole 36b side, and the salai groove 35 is provided in the back pressure chamber 59 of the vane 58. The intermediate pressure Pv, which is a hydraulic pressure, is applied, the projecting output of the vane 58 is returned to the original state before the increase, and the frictional force between the tip of the vane 58 and the inner peripheral surface 49a of the cylinder 40 is also the original force before the increase. It is returned to the extent.

  As described above, the frictional force between the tip of the vane 58 and the inner peripheral surface 49a of the cylinder 40 increases temporarily because chattering of the vane 58 is likely to occur. The increase in power loss accompanying the increase in the frictional force with the inner peripheral surface 49a of 40 can be suppressed to the minimum necessary.

  In the compressor 100 according to this embodiment, the difference between the pressure Pv of the intermediate pressure detection hole 36 a communicating with the hydraulic salai groove 35 loaded on the vane 58 defining the compression chamber 48 and the pressure Ps of the low pressure detection hole 36 b. By operating the valve 38 according to the pressure ΔP, it can be alternatively detected that the internal pressure in the compression chamber 48 is lower than a predetermined reference pressure, and the operation of the valve 38 is Since the hydraulic pressure (pressure Pd) higher than the intermediate pressure Pv is supplied to the high pressure supply passage 37, the internal pressure detection operation in the compression chamber 48 and the high pressure hydraulic pressure supply operation to the high pressure supply passage 37 are performed simultaneously. The configuration can be simplified.

  Furthermore, the compressor 100 of the present embodiment forms a high-pressure supply passage 37 inside the front side block 30 that is a partition wall of the compressor body that divides the compression chamber 48 and the suction chamber 34, and includes an intermediate pressure detection hole 36 a and The low-pressure detection hole 36b and the valve 38 can be provided, and the structure can be simplified.

  Moreover, since the pressure of the refrigerating machine oil R stored in the discharge chamber 21 can be used as the high pressure hydraulic pressure supplied to the high pressure supply passage 37, there is no need to separately prepare the high pressure hydraulic pressure. The structure can be simplified.

It is a longitudinal section showing a vane rotary type compressor which is one embodiment of a gas compressor concerning the present invention. It is a figure which shows the cross section along the AA in FIG. It is the figure which looked at the front side block in FIG. 1 from the same direction as FIG. FIG. 2 is a detailed view of a portion C in FIG. 1, where (a) shows a shielded state of the high-pressure supply passage, and (b) shows a communication state of the high-pressure supply passage.

Explanation of symbols

30 Front side block 32 Bearing portion 32a High pressure supply passage 32b Sliding passage 32c Large diameter portion 33 Oil passage 35 Salai groove 36a Medium pressure detection hole 36b Low pressure detection hole 37 High pressure supply passage 38 Valve 38c Constricted portion 39 Spring Pd High pressure Pv Intermediate pressure Ps Low pressure R Refrigerating machine oil

Claims (3)

A compressor body having a rotating body that rotates around a rotation axis, the rotor having a substantially cylindrical shape, a cylinder having a substantially elliptical cross-sectional profile surrounding the outer peripheral surface of the rotor from the outside, the rotor, and the rotor Two side blocks arranged so as to sandwich the cylinder from both end face sides, and a plurality of cylinders are arranged at a predetermined angular interval in the circumferential direction of the rotor, and can be protruded from the outer peripheral surface of the rotor by a predetermined hydraulic pressure. And a vane whose front end in the protruding state contacts the substantially elliptical inner peripheral surface of the cylinder, and is defined by the rotor, the cylinder, the both side blocks, and the vane by the rotation of the rotor. In the gas compressor that changes the volume of each of the plurality of compression chambers and compresses the gas inside the compression chamber,
In addition to the supply passage for the predetermined hydraulic pressure to the vane, a high-pressure supply passage for supplying a higher hydraulic pressure than the predetermined hydraulic pressure to the vane when the compression chamber is in a compression stroke is formed. With
When the internal pressure of the compression chamber in the compression stroke is lower than a predetermined reference pressure, the high pressure hydraulic pressure is supplied to the high pressure supply passage, and the internal pressure in the compression stroke is the reference pressure. A valve for opening and closing the high-pressure supply passage is provided so that the high-pressure oil pressure is not supplied to the high-pressure supply passage when the pressure is higher.   The high-pressure supply passage is formed in the side block and has an intermediate pressure detection hole that communicates with a hydraulic oil passage that loads the vane that defines the compression chamber when in the compression stroke, and when in the intake stroke A low-pressure detection hole communicating with a low-pressure atmosphere corresponding to the internal pressure of the compression chamber, and the valve is supplied to the high-pressure supply passage from the predetermined hydraulic pressure according to a differential pressure between the medium-pressure detection hole and the low-pressure detection hole. The gas compressor according to claim 1, wherein high pressure hydraulic pressure is also supplied. A housing that covers the outside of the compressor body and has a suction port for sucking gas from the outside and a discharge port for discharging gas to the outside, and communicates with the suction port to connect the compressor body to the compressor body. A suction chamber into which sucked gas is introduced, and a discharge chamber that communicates with the discharge port and discharges gas from the compressor body sandwich the compressor body along the axial direction of the rotary shaft. 3. The gas compressor according to claim 2, wherein the high pressure hydraulic pressure is formed by a pressure of oil stored in the discharge chamber, and the low pressure atmosphere is the suction chamber.

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