JP4459661B2 - Gas compressor - Google Patents

Description

  The present invention relates to, for example, a gas compressor used for compressing refrigerant gas in a cooling device, and more particularly, the rotor can freely enter and exit from the rotor to form a cylinder chamber that compresses the refrigerant gas as the rotor rotates. The present invention relates to a gas compressor provided with a vane.

  For example, a gas compressor used in a cooling device compresses the refrigerant gas sucked from the suction chamber in a cylinder chamber whose volume varies by the operation of the compression mechanism, and discharges the refrigerant gas to the discharge chamber.

Among the compression mechanisms, the compression mechanism of the vane rotary type gas compressor includes a cylindrical cylinder, a pair of side blocks disposed so as to cover both open ends of the cylinder, the cylinder and the pair of sides. And a rotor that is rotatably accommodated in a chamber formed by blocks, and in which a plurality of vanes are provided so as to be freely accessible. As is well known in the art, when the rotor rotates, each vane slides on the circumferential surface of the cylinder mainly by the pressure of oil supplied from the discharge chamber to the back pressure space of each vane. Be energized. Moreover, the centrifugal force which acts on each said vane acts on each said vane by rotation of the said rotor. Due to this urging force, the plurality of vanes define the cylinder chamber together with the rotor by partitioning the chamber so that the refrigerant gas does not leak between the vanes and the peripheral surface of the cylinder. Yes. The refrigerant gas is sucked into the cylinder chamber from the suction chamber when the volume of the cylinder chamber increases, and is compressed in the cylinder chamber and discharged into the discharge chamber when the volume of the cylinder chamber decreases. (For example, refer to Patent Document 1).
JP 2003-254275 A (page 2-6, FIG. 6)

  However, in the gas compressor, for example, when the rotation speed of the rotor is increased in order to speed up the operation of the compression mechanism in order to increase the discharge amount of the compressed gas, the peripheral surface of the cylinder acting on each vane As a result, the sliding resistance between the vane and the peripheral surface of the cylinder increases. That is, when the rotational speed of the rotor increases, the pressure in the discharge chamber increases due to an increase in the discharge amount of the compressed gas, so the pressure of the oil supplied from the discharge chamber to each vane groove Becomes higher. When the sliding resistance between the vane and the peripheral surface of the cylinder increases due to an increase in the urging force to each vane, the rotor requires a large rotational power, and thus the driving efficiency decreases.

  Accordingly, an object of the present invention is to provide a gas compressor in which the sliding resistance between the vane and the peripheral surface of the cylinder does not increase more than necessary regardless of changes in the operating conditions.

In order to solve the above-described problem, the gas compressor according to claim 1 is configured such that a cylinder rotating from a rotor rotating to increase or decrease the volume of the cylinder chamber in order to compress the gas sucked from the suction chamber in the cylinder chamber. A gas compressor provided with a vane that is provided so as to freely enter and exit toward the peripheral wall and acts as an urging force toward the peripheral wall, and the back pressure space is provided to the rotor. It is formed in the rotary shaft member provided along the axis of the rotary shaft member, one end is connected to the back pressure space, the other end is connected to the suction chamber, and the communication is intermittently connected by the on-off valve mechanism. The open / close valve mechanism is provided on the rotary shaft member in the suction chamber, and uses the pressure of the communication passage as an urging force in the opening direction to close the other end of the communication passage; and Energizing suction chamber pressure in the closing direction A valve body arranged to be between, and an elastic member for urging the valve body and in the closing direction to the closed position of the other end, the elastic member, the vanes by the rotation of the rotary shaft member The valve body is biased in a direction opposite to the centrifugal force acting on the valve body by rotation of the rotary shaft member so as to correspond to the centrifugal force acting, and when the biasing force to the vane exceeds a predetermined value In order to reduce the pressure in the back pressure space, an urging force that opens the communication path is set.

The gas compressor according to claim 2 is the cylinder according to claim 1 , wherein the cylinder chamber rotatably accommodates the rotor so that the cylinder chamber has an axis parallel to a rotation axis direction of the rotor. Sliding on the cylinder wall surface defined by the cylinder with both ends open, the front side block and the rear side block arranged to cover the both ends of the cylinder, and the peripheral surface of the cylinder and the inner wall surfaces of the both side blocks It is formed by a plurality of the vanes.

The gas compressor according to claim 3, in the gas compressor according to claim 2, wherein the gas compressed in the previous carboxymethyl Linda chamber is discharged into the discharge chamber, between the back pressure is, each said vane Plurally defined by a plurality of vane grooves formed in the rotor so as to be housed in a removable manner, each back pressure space is formed on the inner wall surface of the rear side block located on the discharge chamber side when viewed from the cylinder chamber. The recess can be communicated with a third space formed in relation to the outer wall surface of the rear side block so as to face the end surface of the rotary shaft member, and the communication The one end of the passage is connected to the third space.

According to a fourth aspect of the present invention, there is provided the gas compressor according to the third aspect, wherein an opening that opens to the suction chamber is formed on a peripheral surface of the rotary shaft member, and the other of the communication passage is formed. The end is open to the peripheral surface of the rotating shaft member at the opening .

According to a fifth aspect of the present invention , in the gas compressor according to the fourth aspect , oil leaks along the rotary shaft member to the rotary shaft member in a space communicating with the suction chamber. The opening is formed in the vicinity of a space communicating with the suction chamber provided with the sealing mechanism .

  In the gas compressor according to claim 1, when the force for urging the vane toward the peripheral wall of the cylinder chamber exceeds a predetermined value, the communication path is opened and the pressure in the back pressure space is reduced. Reduced. For this reason, it is possible to prevent an urging force applied to the vane from becoming unnecessarily large, thereby preventing an increase in sliding resistance between the vane and the peripheral surface of the cylinder.

In the gas compressor according to claim 1 , the on-off valve mechanism opens and closes the communication path based on an urging force to the vane, and therefore the on-off valve mechanism in consideration of a centrifugal force acting on the vane. Therefore, it is possible to more appropriately prevent a decrease in driving efficiency due to an increase in sliding resistance between the vane and the peripheral surface of the cylinder.
Furthermore, in the gas compressor according to claim 1, since the communication path is connected to the suction chamber, the pressure of the suction chamber is introduced when the pressure of the back pressure space is reduced. There is no need to newly introduce external pressure to reduce the biasing force on the vane.
Next, in the gas compressor according to claim 1, the opening of the communication passage is closed by the valve body being urged by the elastic member. By appropriately selecting the urging force, the communication path can be opened, and an increase in sliding resistance between the vane and the peripheral surface of the cylinder can be prevented.

3. The gas compressor according to claim 1 , wherein the on-off valve mechanism is formed by the pressure guided to the communication path through the back pressure space and a centrifugal force acting on the valve body by rotation of the rotor. Opens the communication path. Since the pressures in the back pressure space and the communication path are equal, and the centrifugal force acting on the valve body and the vane changes according to the rotational speed of the rotor, the biasing force of the vane is measured. The communication path can be opened when the urging force exceeds a predetermined value without reducing the urging force.

In the gas compressor according to claim 3 , since the one end of the communication path is connected to the third space, the pressure guided to the back pressure space can be easily introduced into the rotary shaft member. It can be introduced into the formed communication path.

  According to the gas compressor of the present invention, for example, even when the rotor is rotated at a high speed to increase the discharge amount of the compressed gas and the force for energizing the vane becomes large, the vane and the It is possible to prevent the sliding resistance with the peripheral surface of the cylinder from increasing more than necessary. Thus, since the sliding resistance does not increase more than necessary, it is possible to prevent the driving force of the rotor from being greatly impaired, so that the gas can be efficiently compressed and discharged.

  The present invention will be described in detail with reference to the embodiment shown in FIGS.

  FIG. 1 shows a cross-sectional view of a gas compressor 10 used in a cooling device.

  As is well known in the art, the gas compressor 10 takes in refrigerant gas from an evaporator (not shown) that is a cooling unit of a cooling device, and condenses the compressed refrigerant gas as a heat release unit of the cooling device. Supply to a container (not shown). In the evaporator, heat is absorbed from the air around the evaporator by vaporizing the liquefied refrigerant gas, and the surrounding air is cooled. The condenser liquefies refrigerant gas so that the evaporator can easily use heat of vaporization, and sends the liquefied refrigerant gas to the evaporator. The gas compressor 10 supplies the compressed refrigerant gas to the condenser so that the condenser can easily liquefy the refrigerant gas.

  The gas compressor 10 includes a housing 11, a compression mechanism 12 accommodated in the housing 11 to compress the refrigerant gas, and a transmission mechanism 13 that transmits a driving force from a drive source (not shown) to the compression mechanism 12. Is provided. In the illustrated example, the housing 11 includes a housing main body 11a formed of a cylindrical body that is open at one end, and a front housing 11b attached so as to cover the open portion 11c of the housing main body.

  The compression mechanism 12 includes a cylinder 14 having both ends open, which has a cylindrical shape having an inner peripheral surface with an elliptical cross section, a front side block 15 covering one open end 14a, and the other open end 14b of the cylinder 14. The rear side block 16 is covered. In the chamber formed by the cylinder 14 and the side blocks 15 and 16, the inner wall surface 15a of the front side block 15 and the inner wall surface 16a of the rear side block 16 are slidably abutted, and the rotation coincides with the axis of the cylinder 14 A rotor 17 having an axis is rotatably arranged. The rotor 17 has rotation shafts 18 and 19 extending from the rotor 17 in alignment with the rotation axis of the rotor, and both the rotation shafts are a bearing portion 15b and a bearing portion 16b formed in both side blocks 15 and 16, respectively. It is supported by.

  FIG. 2 shows a cross-sectional view taken along the line I-I shown in FIG.

  As shown in FIG. 2, the rotor 17 is formed with five slit-like vane grooves 20 spaced apart from each other in the circumferential direction, and the inner wall surfaces 15 a of both side blocks 15 and 16 are formed in each vane groove 20. , 16a, and a vane 21 having a shape that fits into each vane groove 20 is provided to be freely accessible. As is well known in the art, the pressure of the oil supplied to each vane groove 20 from a pair of recesses 15c and a pair of recesses 16c (see FIG. 1) described later when the rotor 17 is rotated. And the centrifugal force acting on each vane 21 is urged toward the inner peripheral surface 14c of the cylinder 14 to slide on the inner peripheral surface. As a result, the chamber formed by the cylinder 14 and the side blocks 15 and 16 is divided into five spaces by the rotor 17 and the five vanes 21, and five cylinder chambers 22 whose volume is increased or decreased by the rotation of the rotor 17 are formed. Is done.

  The rotor 17 receives driving force from the transmission mechanism 13 and rotates. In the example shown in FIG. 1, the transmission mechanism 13 is an electromagnetic clutch, and is attached to an extension portion 11 d provided on the front housing 11 b so as to extend around the rotary shaft 18. The transmission mechanism 13 includes an annular bearing 23 attached to the extension portion 11d, a pulley 24 rotatably attached to the extension portion 11d via the bearing, and a driving force applied from the pulley to the compression mechanism 12. An armature 25 connected to the rotary shaft 18 to transmit to the rotor 17 and an electromagnet 26 for connecting the pulley 24 and the armature 25 are provided. As is well known in the art, a belt (not shown) is wound around the pulley 24 so as to apply a driving force to the pulley, and the pulley 24 is rotated by the driving force applied through the belt. When the electromagnet 26 is excited to connect the pulley 24 and the armature 25, the driving force can be transmitted to the rotor 17 by the rotation of the pulley 24.

  A suction port 27 is formed in the front housing 11b so that the cylinder chamber 22 can take in the refrigerant gas from the evaporator (not shown) when the rotor 17 rotates. The refrigerant gas taken in from the suction port 27 is stored between the front housing 11b and the front side block 15 in a suction chamber 28 formed in an annular shape so as to surround the rotation shaft 18 of the rotor 17. The refrigerant gas is sucked into the cylinder chamber 22 from the suction chamber 28 by the communication between the cylinder chamber 22 (see FIG. 2) at a position where the volume is increased by the rotation of the rotor 17 and the suction hole 29. The suction hole 29 is formed in the front side block 15, and the suction hole 29 has one end opened to the inner wall surface 15 a of the front side block 15 and the other end of the suction hole 29 opened to the suction chamber 28. 15 is penetrated.

  The refrigerant gas sucked into the cylinder chamber 22 is compressed and becomes high pressure as the volume of the cylinder chamber 22 decreases. As shown in FIG. 2, in order to discharge the compressed refrigerant gas from the cylinder chamber 22, a pair of thin portions 14 d are formed in the vicinity of the short diameter portion of the inner peripheral surface 14 c of the cylinder 14. Each has a discharge hole 30 formed therein. Each discharge hole 30 is provided with a discharge valve 31 that is opened by the pressure of the refrigerant gas so as to allow the refrigerant gas to pass from the inside to the outside of the cylinder 14. Each discharge hole 30 passes through a discharge valve 31 to a discharge chamber 32 (see FIG. 1) formed on the back side of the compression mechanism 12 in the housing body 11a, that is, on the opposite side to the front housing 11b when viewed from the compression mechanism 12. Communication is possible. The high-pressure refrigerant gas compressed in the cylinder chamber 22 and discharged from each discharge hole 30 passes through a cyclone block 33 attached to the rear side block 16 and is stored in the discharge chamber 32 as shown in FIG. The cyclone block 33 is provided with an oil separation part 34. As is well known in the art, the oil separation unit 34 separates oil contained in the refrigerant gas from the refrigerant gas when the refrigerant gas passes through the cyclone block 33. The separated oil is stored below the discharge chamber 32. The high-pressure refrigerant gas compressed in the cylinder chamber 22 and discharged from the discharge holes 30 is temporarily stored in the discharge chamber 32, thereby removing pulsation generated during discharge, and a discharge port 35 formed in the housing body 11a. And supplied to a condenser (not shown).

  In the gas compressor 10, as is well known in the art, between the members of the compression mechanism 12 that performs relative motion, for example, the rotating shafts 18 and 19 of the rotor 17 and the bearing portions that support the rotating shafts 18 and 19. High-pressure oil stored below the discharge chamber 32 is supplied between 15b and 16b in order to make the sliding due to their relative motion smooth. This oil passes through the oil supply passage 36 having oil supply passage portions 36a, 36b, 36c formed in the cylinder 14 and both side blocks 15, 16 due to the high pressure of the refrigerant gas in the discharge chamber 32, and the compression mechanism 12 Supplied between the sliding members. A part of this oil goes to the transmission mechanism 13 along the rotation shaft 18, but the rotation shaft 18 is provided with a seal mechanism 37 so as to surround the rotation shaft, so that the oil reaches the transmission mechanism 13. That is prevented. Part of the oil supplied between the members of the compression mechanism 12 passes between the rotary shafts 18 and 19 of the rotor 17 and the bearing portions 15b and 16b that support the rotary shafts, and then the front side block 15. The oil is supplied to a pair of recesses 15c for oil storage formed on the bottom and a pair of recesses 16c formed on the rear side block 16. A pair of recesses 15 c and a pair of recesses 16 c called “Salai” intermittently communicate with each vane groove 20 during rotation of the rotor 17 to supply oil to each vane groove 20 as described above. The space defined by each vane groove 20 functions as a back pressure space for each vane 21.

  The chamber formed by the cylinder 14 and the side blocks 15 and 16 is partitioned by the rotor 17 into a space near the two long diameter portions of the inner peripheral surface 14 c of the cylinder 14. Each cylinder chamber 22 performs a process of simultaneously sucking and compressing by increasing or decreasing the volume in the space in the vicinity of the major axis portion. In this way, the recesses 15c and the recesses 16c correspond to the spaces in the vicinity of the two long diameter portions, respectively, so that each cylinder chamber 22 performs a suction and compression process in the vicinity of the two long diameter portions. It is provided in pairs in the diameter direction. As is well known in the art, in order to suppress the fluctuation of the pressure in each vane groove 20 due to the entry / exit of each vane 21, the pair of recesses 16 c are respectively connected to the space 39 through a pair of connection passages 38. It communicates by connecting.

  The space 39 is formed by the end face 16e of the boss part 16d and the end face 33a of the cyclone block 33 facing the end face by fitting the boss part 16d formed with the bearing part 16b of the rear side block 16 and the cyclone block 33. It is formed between both end faces 16e and 33a. The space 39 is prevented from leaking oil by a seal ring 40 disposed so as to surround the boss portion 16d. The end surface 19a of the rotating shaft 19 faces the space 39 so that the end surface 19a of the rotating shaft 19 inserted through the bearing portion 16b and the end surface 16e of the boss portion 16d are located on the same plane.

  When the rotor 17 rotates, the pressure of the oil in each vane groove 20 increases, and the rotational speed of the rotor 17 increases to increase the centrifugal force acting on each vane 21, thereby increasing the biasing force to each vane 21. Then, the sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14 increases due to the increase in the urging force. In such a case, in order to reduce the urging force to each vane 21, a communication passage 50 is provided for allowing oil in each vane groove 20 as a back pressure space of each vane 21 to flow into the suction chamber 28. Yes.

  The communication path 50 is formed in the rotor 17 and the rotation shafts 18 and 19 so that the rotation axis of the rotor 17 and the center line coincide with each other and extend. One end of the communication path 50 is open to the space 39 at the end surface 19a of the rotating shaft 19, and the other end of the communication path 50 is an opening 18b (see FIG. 5) formed on the peripheral surface 18a of the rotating shaft 18 via the communication path 50a. 3)), the suction chamber 28 is opened. An opening / closing valve mechanism 55 is provided in the opening 18 b, and the opening 18 b is opened and closed by the operation of the opening / closing valve mechanism 55.

  FIG. 3 shows an enlarged cross section of the on-off valve mechanism 55 obtained along the line II-II shown in FIG.

  As shown in FIG. 3, the on-off valve mechanism 55 includes a backup ring 56 that is formed so as to surround the rotating shaft 18 and is fixed to the rotating shaft 18. The backup ring 56 has an annular support portion 56a (see FIG. 1) extending in the radial direction from the rotary shaft 18 and a support portion 56a so as to cover the opening 18b with a space from the peripheral surface 18a of the rotary shaft 18. To a flange portion 56b extending along the rotation axis direction of the rotation shaft 18. The opening 18b is provided with an opening / closing valve body 57 that closes the opening, and the opening / closing valve body is urged by a coil spring 58 to close the opening 18b. The coil spring 58 has one end attached to the on-off valve body 57 and the other end attached to the flange portion 56b. The coil spring 58 opposes the force acting on the on-off valve body 57 due to the difference between the oil pressure in the communication passage 50 and the pressure in the suction chamber 28 and the combined force of the centrifugal force acting on the on-off valve body 57 due to the rotation of the rotor 17. Thus, the on-off valve body 57 is urged toward the closed position of the opening 18b. For this reason, the combined force of the oil pressure in the communication passage 50 that biases the on-off valve body 57 in the opening direction and the centrifugal force acting on the on-off valve body 57, and the on-off valve body 57 in the closing direction. The opening / closing valve body 57 opens the opening 18b when the difference from the pressure of the suction chamber 28 exceeds the biasing force of the coil spring 58 that biases the opening / closing valve body 57 in the closing direction. The value is defined by the biasing force of the coil spring 58. By appropriately setting the urging force of the coil spring 58, the opening is applied when the urging force applied to each vane 21 by the oil pressure in each vane groove 20 and the centrifugal force acting on each vane 21 exceeds a predetermined value. The part 18b can be opened. That is, since the communicating path 50 is connected to the space 39, the inside of each vane groove 20 when communicating with the pair of recesses 16c, the communicating path 50, the connecting path 38, the space 39, and the pair of recesses 16c. Each oil has an equal pressure. Further, since the on-off valve body 57 and each vane 21 rotate about the rotation axis of the rotor 17, the centrifugal force acting on the on-off valve body 57 and the centrifugal force acting on each vane 21 are both rotational speeds of the rotor 17. Changes in proportion to Therefore, by appropriately selecting the urging force of the coil spring 58, the opening 18b is opened when the urging force to each vane exceeds a predetermined value without measuring the urging force to each vane 21. Can be made. As the sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14 increases, the driving efficiency of the rotor 17 decreases. However, the opening 18b is opened so that the driving efficiency does not decrease below the allowable value. It is desirable to select a coil spring 58 having a biasing force.

  As described above, the gas compressor 10 is powered by a belt (not shown) wound around the pulley 24 and rotates the rotor 17 via the rotating shaft 18 as described above. The refrigerant gas in the suction chamber 28 is sucked into the cylinder chamber 22 by the rotation of the rotor 17, and the sucked refrigerant gas is compressed as the volume of the cylinder chamber 22 decreases. The high pressure refrigerant gas compressed in the cylinder chamber 22 opens the discharge valve 31 due to the high pressure, is stored in the discharge chamber 32 through the discharge hole 30 and the cyclone block 33, and is discharged from the discharge port 35.

  When the gas compressor 10 increases the rotational speed of the rotor 17 to increase the discharge amount of the compressed refrigerant gas, the urging force to the inner peripheral surface 14c of the cylinder 14 acting on each vane 21 increases. That is, since the discharge amount of the compressed refrigerant gas per unit time is increased, the pressure of the refrigerant gas stored in the discharge chamber 32 is increased, so that the recess 15c and the recess are formed from the discharge chamber 32 through the oil supply path 36. The pressure of the oil supplied to the place 16c becomes high. Further, when the rotational speed of the rotor 17 increases, the centrifugal force acting on each vane 21 increases. The urging force acting on each vane 21 is a combined force of the pressure of the oil supplied to each vane groove 20 and the centrifugal force acting on each vane 21 due to the rotation of the rotor 17. The biasing force acting on the vane 21 increases. As described above, the urging force acting on each vane 21 is increased and the sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14 is increased, which adversely affects the operation of the gas compressor 10. When the driving efficiency is likely to be lower than the allowable value, as described above, the opening / closing valve body 57 of the opening / closing valve mechanism 55 provided in the opening 18b to which the communication path 50 is connected opens the opening 18b. When the opening 18b is opened, the oil in the communication passage 50 flows out to the suction chamber 28, which is a space lower than the pressure of the oil, so that the back pressure space of each vane 21, that is, each vane groove 20 The oil pressure drops. For this reason, the sliding resistance between each vane 21 and the inner peripheral surface 14c does not exceed a predetermined value, and adverse effects on the operation of the gas compressor 10 due to the increase in the sliding resistance are prevented. When the oil pressure in the communication passage 50 decreases due to the oil flowing out from the communication passage 50 into the suction chamber 28, the on-off valve body 57 of the on-off valve mechanism 55 closes the opening 18 b again by the biasing force of the coil spring 58. To do.

  For this reason, in the gas compressor 10, for example, even when the rotational speed of the rotor 17 is increased in order to increase the discharge amount of the compressed refrigerant gas, the urging force acting on each vane 21 is a predetermined value or more. It will never be. Therefore, it is possible to prevent a decrease in the driving efficiency of the rotor 17 caused by an increase in sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14.

  Further, the on-off valve mechanism 55 uses the combined force of the oil pressure in the communication passage 50 and the centrifugal force applied to the on-off valve body 57 by the rotation of the rotor 17. The communication path 50 can be intermittently connected according to the sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14 without using a pressure gauge for detecting pressure or a tachometer for detecting the rotational speed of the rotor 17.

  Since the other end of the communication path 50 is connected to the suction chamber 28, even if the communication path 50 is conducted to reduce the pressure of the oil in each vane groove 20, the oil remains outside the gas compressor 10. It will circulate within the gas compressor without flowing out. For this reason, by reducing the pressure of the oil in each vane groove 20, the oil in the gas compressor 10 is reduced, and for example, the operation of the compression mechanism 12 is not hindered.

  Therefore, according to the gas compressor 10 described in the present embodiment, it is possible to prevent the sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14 from increasing more than necessary regardless of the change in the operating condition. it can.

  In order to use the resultant force of the centrifugal force generated by the rotation of the rotor 17 and the pressure of the oil in the communication path 50 for the operation of the on-off valve mechanism 55 for intermittently connecting the communication path 50, for example, as shown in FIGS. In this way, the communication path 60 and the on-off valve mechanism 65 can be configured. FIG. 5 is an enlarged sectional view showing the vicinity of the communication path 60 and the on-off valve mechanism 65 in FIG.

  One end of the communication path 60 opens to the space 39 and the other end opens to the suction chamber 28. The on-off valve mechanism 65 energizes the on-off valve body 66 to close the communication passage 60, a spherical on-off valve body 66 that closes the communication passage 60, an enlarged diameter passage 67 that movably accommodates the on-off valve body, and the communication passage 60. And a base 69 to which the coil spring is attached. One end of the enlarged diameter passage 67 is connected to the communication passage 60 by an enlarged diameter portion 67 a having a shape that fits with the on-off valve body 66, and the other end opens the rotary shaft 18. The base 69 closes the other end of the enlarged diameter passage 67. When the opening / closing valve body 66 is fitted to the enlarged diameter portion 67a of the enlarged diameter passage 67, the valve seat opening portion 67b of the enlarged diameter portion 67a is closed and the communication passage 60 is blocked. Similarly to the above-described on-off valve mechanism 55 (see FIG. 2), the on-off valve mechanism 65 works on the oil pressure in each vane groove 20 and each vane 21 by appropriately selecting the urging force of the coil spring 68. When the urging force to each vane 21 due to the centrifugal force exceeds a predetermined value, the communication path 60 can be conducted.

  In the example shown in FIG. 4, the communication path 60 is formed to have a center line different from the rotation axis of the rotor 17. However, if the communication path 60 is eccentric from the rotation axis of the rotor 17, vibration may occur during operation of the gas compressor 10. Further, if the communication path 60 is eccentric from the rotation axis of the rotor 17, the communication path 60 moves when the rotor 17 is rotating, so that the oil in the space 39 is difficult to flow into the communication path 60. . For this reason, it is desirable to form the center line of the communication path 60 so as to coincide with the rotation axis of the rotor 17 as in the communication path 50 (see FIG. 1).

  In the on-off valve mechanisms 55, 65, coil springs 58, 68 are used as elastic members for applying an urging force toward the urging position to the on-off valve bodies 57, 66. As long as it urges the opening and closing valve bodies 57 and 66 against the combined force of the centrifugal force to the bodies 57 and 66 and the pressure of the oil in the communication passage 50, it is not limited to the above example. Absent. For example, a spring such as a leaf spring may be used, and rubber may be used instead of the spring.

  The backup ring 56 of the on-off valve mechanism 55 has a shape surrounding the rotary shaft 18, but it is sufficient that a coil spring 58 can be attached so as to bias the on-off valve body 57, for example, the rotary shaft 18. It can also be formed as an arm-like protrusion extending so as to cover the opening 18b with a gap from the above, and is not limited to the above example.

  In the above-described example, the on-off valve bodies 57 and 66 of the on-off valve mechanisms 55 and 65 have a predetermined combined force due to the oil pressure in the communication passage 50 and the centrifugal force applied to the on-off valve bodies 57 and 66 due to the rotation of the rotor 17. Since the opening 18b is opened when the value of is exceeded, the pressure of the oil in the communication passage 50 is low even when the rotation of the rotor 17 is low speed and the centrifugal force to the on-off valve bodies 57 and 66 hardly acts. When the height increases, the communication paths 50 and 60 become conductive. Further, when the rotational speed of the rotor 17 is increased, for example, when the stroke speed for liquefying the refrigerant gas in the condenser (not shown) of the cooling device is large and the pressure in the discharge chamber 32 does not change. However, if the centrifugal force applied to each vane 21 increases as the rotational speed of the rotor 17 increases, the communication paths 50 and 60 become conductive.

  Further, the communication passages 50 and 60 provided to reduce the urging force to each vane 21 and the on-off valve mechanisms 55 and 65 that connect and disconnect the communication passages are not limited to the above examples. The communication passages 50 and 60 may not be connected to the space 39, and the on-off valve mechanisms 55 and 65 are opened by the pressure in the communication passages 50 and 60 without applying centrifugal force to the on-off valve bodies 57 and 66. Can be formed. For example, the communication path is provided so that one end opens to a pair of recesses 15 c formed in the front side block 15 and the other end opens to the suction chamber 28. In this case, a relief valve is provided as an on-off valve mechanism in the communication path, and the oil in each vane groove 20 is adjusted when the oil pressure in each vane groove 20 exceeds a predetermined value by adjusting the relief valve. It can be made to flow into the suction chamber 28, and the sliding resistance between each vane 21 and the inner peripheral surface 14c of the cylinder 14 can be prevented from increasing more than necessary. However, if the communication paths 50 and 60 and the on-off valve mechanisms 55 and 65 are configured as described above, the centrifugal force acting on each vane 21 can also be taken into consideration, so that each vane 21 and the inner peripheral surface 14c of the cylinder 14 can be more appropriately The increase in sliding resistance can be prevented.

  In the above-described embodiment, an example is shown in which the present invention is applied to a concentric rotor type compressor in which the rotor 17 is provided so as to have an axis of rotation on the axis of the cylindrical cylinder 14 having an elliptical inner shape. In addition, the present invention may be applied to an eccentric rotor type compressor in which a rotor is disposed inside a cylindrical cylinder having a circular inner shape so as to have a rotation axis different from the axis of the cylinder. It is not limited to examples.

  In the above-described embodiment, the gas compressor 10 is used in the cooling device and compresses the refrigerant gas. However, the present invention is not limited to the above-described embodiment, and may be used when it is desired to obtain a compressed gas. it can.

It is sectional drawing which shows an example of the gas compressor 10 which concerns on this invention. It is sectional drawing obtained along the II line | wire shown in FIG. FIG. 2 is an enlarged cross-sectional view showing an on-off valve mechanism 55 obtained along the line II-II shown in FIG. 1. It is sectional drawing which shows the other example of the gas compressor 10 which concerns on this invention. FIG. 2 is an enlarged cross-sectional view showing the vicinity of a communication path 60 and an on-off valve mechanism 65 in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Gas compressor 14 Cylinder 14a Inner peripheral surface 15 Front side block 15a Inner wall surface 16 Rear side block 16a Inner wall surface 16c Recess 17 Rotor 18, 19 Rotating shaft 18a Peripheral surface 18b Opening portion 19a End surface 20 Vane groove 21 Vane 22 Cylinder chamber 28 Suction chamber 32 Discharge chamber 39 (Third) space 50, 60 Communication passages 55, 65 Open / close valve mechanisms 57, 66 Open / close valve bodies 58, 68 Coil spring 67b (as an elastic member) Valve seat opening portion

Claims (5)

In order to compress the gas sucked from the suction chamber in the cylinder chamber, the pressure introduced to the peripheral wall of the cylinder chamber from the rotating rotor to increase or decrease the volume of the cylinder chamber and the pressure guided to the back pressure space is A gas compressor having a vane that acts as an urging force toward the peripheral wall,
The back pressure space is formed in the rotary shaft member provided in the rotor along the axis of the rotary shaft member, one end is connected to the back pressure space, the other end is connected to the suction chamber, and is opened and closed. Having a communication path in which communication is interrupted by a valve mechanism;
The on-off valve mechanism is provided in the rotary shaft member in the suction chamber, and uses the pressure of the communication passage as an urging force in the opening direction to close the other end of the communication passage, and the pressure of the suction chamber. A valve body arranged to be a biasing force in the closing direction, and an elastic member that biases the valve body in the closing direction to the closed position of the other end,
The elastic member urges the valve body in a direction opposite to the centrifugal force acting on the valve body by the rotation of the rotary shaft member so as to correspond to the centrifugal force acting on the vane by the rotation of the rotary shaft member, A gas compressor characterized by being set to an urging force that opens the communication path so as to reduce the pressure in the back pressure space when the urging force to the vane exceeds a predetermined value.   The cylinder chamber includes a cylindrical cylinder having both ends open and rotatably accommodates the rotor so as to have an axis parallel to the rotation axis direction of the rotor, and a front side block disposed to cover the both ends of the cylinder. 2. The gas compression according to claim 1, comprising: a rear side block; and a plurality of the vanes sliding on a cylinder wall surface defined by a peripheral surface of the cylinder and inner wall surfaces of the two side blocks. Machine.   The gas compressed in the cylinder chamber is discharged into a discharge chamber, and the back pressure space is defined by a plurality of vane grooves formed in the rotor to accommodate the vanes so as to be able to enter and exit, respectively. The back pressure space can communicate with a recess provided in the inner wall surface of the rear side block located on the discharge chamber side when viewed from the cylinder chamber, and the recess is a surface of the end surface of the rotating shaft member. The first side of the communication path is connected to the third space, and communicates with a third space formed in association with the outer wall surface of the rear side block. The gas compressor described in 1.   An opening that opens to the suction chamber is formed on the peripheral surface of the rotating shaft member, and the other end of the communication path is open to the peripheral surface of the rotating shaft member at the opening. The gas compressor according to claim 3. The rotary shaft member is provided with a seal mechanism for preventing oil from leaking along the rotary shaft member in a space communicating with the suction chamber.
The gas compressor according to claim 4, wherein the opening is formed in the vicinity of a space communicating with the suction chamber provided with the seal mechanism.

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