JP2015117596A - Variable displacement type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable displacement type compressor having a simple structure and capable of promoting discharging of lubricant oil at high temperature.SOLUTION: This invention relates to a variable displacement type compressor 100 constituted in such a way that a pressure releasing passage 147 is formed by one flow passage and the compressor comprises metering means 103c arranged at the pressure releasing passage 147 and discharging restriction means 170 having a restriction part 170b which is arranged at a crank chamber side pressure releasing passage of a crank chamber 140 rather than the metering means 103c in the pressure releasing passage so as to restrict discharging of lubricant oil in the crank chamber 140 toward an intake chamber 141, and the discharging restriction 170 is constituted in such a way that when the restriction is being carried out, an opening area of the pressure releasing passage at the crank chamber at an arranged location of the restriction part 170b is set to be larger than a flow passage sectional area of the metering means 103c and when a temperature of the crank chamber 140 is equal to or higher than a prescribed temperature, the opening area is increased to enable the restriction to be released.

Description

  The present invention relates to a variable displacement compressor that compresses refrigerant gas, and more particularly to a variable displacement compressor used in a vehicle air conditioner system or the like.

  In a variable displacement compressor used in a conventional vehicle air conditioner system or the like, a piston in a cylinder bore is reciprocated by the rotation of a drive shaft to compress refrigerant gas sucked into the cylinder bore from the suction chamber and thereby set a discharge chamber. And a pressure supply passage that communicates the discharge chamber and the crank chamber behind the piston, and a pressure relief passage that communicates the crank chamber and the suction chamber. This type of variable capacity compressor is configured by adjusting the opening of the pressure supply passage with a control valve or the like while providing a throttle in the pressure release passage to restrict the refrigerant gas flow rate in the pressure release passage to a predetermined value. The pressure in the crank chamber is adjusted, thereby changing the stroke amount of the piston, and the discharge capacity of the refrigerant from the cylinder bore can be changed.

  In this type of variable displacement compressor, lubricating oil is stored in the crank chamber for lubrication between the mechanical portions in the crank chamber. A part of the stored lubricating oil is scattered in the crank chamber in the form of an oil mist by rotating parts such as a swash plate attached to the drive shaft. High-pressure refrigerant gas flows into the crank chamber. The refrigerant gas that flows into the crank chamber includes a discharge gas that flows in through the pressure supply passage during the discharge capacity change control, and a so-called blow-by gas that flows through the gap between the cylinder bore and the piston during the compression process. These flow from the crank chamber to the suction chamber through the pressure relief passage. At this time, the lubricating oil scattered in the crank chamber also tends to flow into the suction chamber along with the refrigerant gas along with the refrigerant gas. That is, part of the lubricating oil stored in the crank chamber tends to flow into the suction chamber.

  Here, when a part of the lubricating oil stored in the crank chamber flows into the suction chamber together with the refrigerant gas, the lubricating oil is compressed along with the refrigerant gas and flows out from the discharge chamber to the vehicle-side external refrigerant circuit. Will do. As the amount of lubricating oil flowing out to the external refrigerant circuit increases, the system efficiency of the air conditioner decreases. Therefore, the amount of lubricating oil flowing out to the external refrigerant circuit is reduced, that is, the OCR (oil circulation rate) is reduced. It has been demanded. Therefore, it is desirable to store the lubricating oil in the crank chamber as much as possible. On the other hand, for example, when the rotational speed of the drive shaft exceeds the normal rotational speed and reaches high speed rotation, and the amount of heat generated by the stirring and shearing of the lubricating oil by the rotating parts such as the swash plate becomes abnormally high, the viscosity of the lubricating oil becomes There is a risk that appropriate lubrication cannot be performed due to a decrease. In this case, priority is given to reducing the amount of heat generated by stirring or shearing of the lubricating oil, and there is a demand for the construction of an oil management structure that reduces the amount of lubricating oil stored in the crank chamber.

  An example of a variable displacement compressor having this type of oil management structure is described in Patent Document 1. In this variable displacement compressor, a throttle is provided on the suction chamber side of the pressure release passage communicating the crank chamber and the suction chamber to restrict the refrigerant gas flow rate to a predetermined value, and the pressure release passage to the crank chamber side is also provided. The connection passage is divided into two paths, one of the paths is always opened so that the crank chamber pressure can be adjusted appropriately, and the other passage is opened only when the temperature of the crank chamber is equal to or higher than a predetermined temperature. In this configuration, the amount of lubricating oil in the crank chamber is reduced by promoting the discharge of the lubricating oil in the crank chamber to the suction chamber side.

Japanese Patent Laid-Open No. 2007-9720

  However, in the variable displacement compressor described in Patent Document 1, the connection passage to the crank chamber side of the pressure release passage is branched into two paths, and a branch passage that is not originally required for adjusting the pressure in the crank chamber is provided. The That is, apart from the original pressure relief passage, it is necessary to form a passage exclusively for lubricating oil discharge, so that the structure becomes complicated and the manufacturing cost increases, and there is room for improvement.

  The present invention has been made paying attention to the above problems, and has a variable capacity capable of facilitating the discharge of lubricating oil in the crank chamber into the suction chamber at a high temperature without affecting the pressure adjustment in the crank chamber. An object is to provide a mold compressor.

  For this reason, the variable capacity compressor of the present invention reciprocates the piston in the cylinder bore by the rotation of the drive shaft, compresses the refrigerant gas sucked into the cylinder bore from the suction chamber, and discharges it outside through the discharge chamber. A compression mechanism, a pressure supply passage communicating the discharge chamber and the crank chamber behind the piston, and a pressure release passage communicating the crank chamber and the suction chamber, and a flow rate of the pressure release passage In the variable displacement compressor capable of adjusting the pressure of the crank chamber and changing the discharge capacity of the refrigerant by adjusting the opening of the pressure supply passage. And a throttle means provided in the pressure release passage, and the suction chamber for the lubricating oil in the crank chamber disposed in the crank chamber side pressure release passage closer to the crank chamber than the throttle means in the pressure release passage. To the side An emission suppression means having a suppression portion that suppresses discharge, and when the suppression is performed, an opening area of the crank chamber side pressure release passage at an arrangement position of the suppression portion is determined from a flow passage cross-sectional area of the throttle means. And a discharge suppression means configured to increase the opening area and release the suppression when the crank chamber temperature is equal to or higher than a predetermined temperature.

According to the variable displacement compressor of the present invention, the suppressing portion disposed in the crank chamber side pressure release passage on the crank chamber side from the throttle means is one of the pressure release passages in which the crank chamber and the suction chamber communicate with each other. The amount of the lubricating oil scattered in the crank chamber discharged along with the refrigerant gas flowing into the crank chamber can be reduced by the discharge suppression means. According to this variable capacity compressor, the opening area of the crank chamber side pressure release passage at the location where the suppressing portion is disposed is scattered in the crank chamber in a state where the opening area is set larger than the flow passage cross-sectional area of the throttle means. Suppressing the discharge of the lubricating oil to the suction chamber side and releasing the restriction of the discharge of the lubricating oil to the suction chamber side when the temperature of the crank chamber is equal to or higher than the predetermined temperature, the lubricating oil is discharged to the suction chamber side. In addition, the flow rate of the pressure relief passage can be regulated to a predetermined value by the throttling means at all times, that is, at any time after the cancellation of the suppression and during the suppression. Therefore, the pressure in the crank chamber can be appropriately adjusted by always regulating the flow rate of the pressure release passage regardless of whether or not the discharge is canceled by the discharge suppressing means. In addition, the pressure relief passage that connects the crank chamber and the suction chamber in a single path can also be used as a lubricant discharge passage, and a separate passage for lubricating oil discharge is formed separately from the pressure relief passage. There is no need to do.
In this way, it is possible to provide a variable displacement compressor that can facilitate the discharge of the lubricating oil in the crank chamber into the suction chamber at a high temperature with a simple structure without affecting the pressure adjustment of the crank chamber. .

1 is a longitudinal sectional view of a variable capacity compressor according to a first embodiment of the present invention. It is an enlarged view of the pressure release passage part shown in FIG. It is a front view of the cylinder block seen from the crank chamber side of this embodiment. It is a fragmentary sectional view of the AA arrow shown in FIG. 3, and shows a state when discharge | emission of lubricating oil is suppressed by the discharge | emission suppression means. It is a fragmentary sectional view of the AA arrow shown in FIG. 3, and shows a state when the suppression of the discharge of the lubricating oil by the discharge suppression means is released. It is a figure for demonstrating the discharge | emission suppression means of the variable displacement compressor which concerns on 2nd Embodiment of this invention, and is the figure which showed the state at the time of discharge | emission suppression with the fragmentary sectional view in the same cross section as FIG. It is the figure which showed the protrusion part seen from the B arrow direction shown in FIG. It is a longitudinal section of a variable capacity type compressor about a reference example of the present invention. It is an enlarged view of the pressure release passage part shown in FIG. It is a front view of the cylinder block seen from the crank chamber side of the reference example. It is a fragmentary sectional view of the CC arrow shown in Drawing 10, and shows a state when discharge of lubricating oil is controlled by discharge control means. It is a fragmentary sectional view of the CC arrow shown in FIG. 10, and shows a state when the suppression of the discharge of the lubricating oil by the discharge suppression means is released. It is a figure for demonstrating the modification of the variable capacity type compressor 100 'of the said reference example, and is a fragmentary sectional view in the same cross section as FIG. It is a figure for demonstrating another modification of the variable capacity type compressor 100 'of the said reference example, and is a fragmentary sectional view in the same cross section as FIG.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a longitudinal sectional view of a swash plate type clutchless variable displacement compressor (hereinafter referred to as “variable displacement compressor”) 100 as an example of a variable displacement compressor to which the present invention is applied.
In the present embodiment, the variable capacity compressor 100 is used by being incorporated in a vehicle air conditioner system, and is attached to an engine on the vehicle side when used and connected to a refrigerant circuit (evaporator and condenser) not shown. Has been. Here, as the refrigerant, for example, an appropriate refrigerant such as R134a, R1234yf, and carbon dioxide is applied.
In FIG. 1, the variable capacity compressor 100 includes a cylinder block 101 having a plurality of cylinder bores 101a, a front housing 102 provided at one end of the cylinder block 101, a valve plate 103 at the other end of the cylinder block 101, and the like. And a cylinder head 104 provided via the cylinder.

  For example, a discharge valve forming body 138 a is provided on the end surface of the valve plate 103 on the cylinder head 104 side, and a head gasket 138 b is provided between the discharge valve forming body 138 a and the cylinder head 104. On the other hand, a suction valve forming body 139 a is provided on the end face of the valve plate 103 on the cylinder block 101 side, and a cylinder gasket 139 b is provided between the suction valve forming body 139 a and the cylinder block 101.

The cylinder block 101 has a cylinder bore 101a and a center bore 101b. A plurality of cylinder bores 101a are arranged in the cylinder block 101 in the circumferential direction. The center bore 101b is disposed so as to be surrounded by each cylinder bore 101a. The cylinder block 101 also forms an introduction passage 101c that becomes a part of a crank chamber side pressure release passage in a pressure release passage 147 described later.
In the present embodiment, the cylinder block 101 corresponds to a “formed body” according to the present invention.

  Specifically, as shown in FIG. 2, the center bore 101b has a first center bore 101b1 facing a crank chamber 140, which will be described later, a second center bore 101b2 facing the valve plate 103, and a slide bearing 131. And a third center bore 101b3 to be supported.

As shown in FIGS. 2 and 3, the first center bore 101b1 is formed inside the plurality of cylinder bores 101a, and on the crank chamber side wall surface of the cylinder block 101, a peripheral wall 101b11 serving as a forming wall of each cylinder bore 101a, and a crank chamber 140 and the bottom wall 101b12 facing each other are formed in a concave shape. Thus, the cylinder block 101 has a recess on the side wall surface of the crank chamber.
In the present embodiment, the first center bore 101b1 corresponds to a “concave portion” according to the present invention, and the bottom wall 101b12 corresponds to a “bottom portion” according to the present invention.
The second center bore 101b2 is formed in a concave shape with a peripheral wall 101b21 formed inside the plurality of cylinder bores 101a and a bottom wall 101b22 facing the valve plate 103. On the bottom wall 101b22, a housing portion that houses the adjustment screw 135 is formed.
The third center bore 101b3 is formed penetrating radially inward from the peripheral wall 101b11 of the first center bore 101b1 and the peripheral wall 101b21 of the second center bore 101b2.

  Returning to FIG. 1, the crank chamber 140 is defined by the cylinder block 101 and the front housing 102. The crank chamber 140 is located behind a piston 136 described later. A drive shaft 110 is provided that crosses the center of the crank chamber 140 and is rotatably supported through the bottom wall 101b12 of the first center bore 101b1. A swash plate 111 is disposed around an intermediate portion of the drive shaft 110 in the axial direction. The swash plate 111 is connected to a rotor 112 fixed to the drive shaft 110 via a link mechanism 120 so that the tilt angle with respect to the central axis of the drive shaft 110 is variable.

The link mechanism 120 includes a first arm 112 a projecting from the rotor 112, a second arm 111 a projecting from the swash plate 111, and one end rotating relative to the first arm 112 a via the first connecting pin 122. A link arm 121 that is movably coupled and has the other end pivotally coupled to the second arm 111a via a second coupling pin 123.
In the present embodiment, the link mechanism 120 corresponds to a “connecting unit” according to the present invention.

  The through hole 111b of the swash plate 111 is formed in a shape that allows the swash plate 111 to tilt within the range of the maximum inclination angle and the minimum inclination angle, and the minimum inclination angle restricting portion that contacts the drive shaft 110 is formed in the through hole 111b. . When the inclination angle of the swash plate 111 when the swash plate 111 is orthogonal to the drive shaft 110 is 0 °, the minimum inclination restriction portion of the through hole 111b is formed so that the swash plate 111 can be inclined to substantially 0 °. Yes. Further, the tilt displacement (tilt) of the swash plate 111 in the direction of increasing the tilt angle is regulated by the swash plate 111 coming into contact with the rotor 112. Therefore, the inclination angle of the swash plate 111 becomes the maximum inclination angle when the swash plate 111 contacts the rotor 112.

  Around the drive shaft 110 between the rotor 112 and the swash plate 111, an inclination reduction spring 114 that urges the swash plate 111 toward the minimum inclination angle is mounted. Further, around the drive shaft 110 between the swash plate 111 and the spring support member 116 provided on the drive shaft 110, the inclination angle is increased so that the inclination angle of the swash plate 111 is increased to a predetermined inclination angle smaller than the maximum inclination angle. A spring 115 is attached. The biasing force of the tilt angle increasing spring 115 at the minimum tilt angle is set larger than the biasing force of the tilt angle decreasing spring 114. Therefore, when the drive shaft 110 is not rotating, the swash plate 111 is positioned at a predetermined tilt angle that balances the biasing force of the tilt angle decreasing spring 114 and the biasing force of the tilt angle increasing spring 115.

  One end of the drive shaft 110 extends through the boss portion 102a of the front housing 102 to the outside of the front housing 102, and is connected to a power transmission device (not shown). A shaft seal device 130 is inserted between the drive shaft 110 and the boss portion 102a to shut off the crank chamber 140 and the external space. The other end of the drive shaft 110 passes through the center bore 101b and is supported by the thrust plate 132.

  The coupling body of the drive shaft 110 and the rotor 112 is supported by bearings 131 and 133 in the radial direction, and supported by the bearing 134 and the thrust plate 132 in the thrust direction, and power from an external drive source (vehicle engine) is transmitted to the power transmission device. The drive shaft 110 rotates in synchronization with the power transmission device. The clearance between the drive shaft 110 and the thrust plate 134 is adjusted to a predetermined clearance by the adjustment screw 135.

  A piston 136 is disposed in the cylinder bore 101a. The outer peripheral portion of the swash plate 111 is accommodated in the inner space of the end of the piston 136 that protrudes toward the crank chamber 140. The swash plate 111 is interlocked with the piston 136 via a pair of shoes 137. Thereby, the piston 136 reciprocates in the cylinder bore 101a by the rotation of the swash plate 111.

The cylinder head 104 is formed with a suction chamber 141 defined by an annular partition wall at the center and a discharge chamber 142 surrounding the suction chamber 141 in an annular shape.
The suction chamber 141 is disposed on an extension line of the central axis O of the drive shaft 110, and is provided in, for example, a communication hole (not shown) formed in the head gasket 138 b and the discharge valve forming body 138 a and the valve plate 103. The cylinder bore 101a communicates with the suction hole 103a and a suction valve (not shown) formed in the suction valve forming body 139a.
The discharge chamber 142 includes, for example, a communication hole (not shown) formed in the head gasket 138b, a discharge valve (not shown) formed in the discharge valve forming body 138a, a discharge hole 103b provided in the valve plate 103, It communicates with the cylinder bore 101a through a communication hole (not shown) formed in the suction valve forming body 139a.

The front housing 102, the cylinder block 101, the cylinder gasket 139b, the suction valve forming body 139a, the valve plate 103, the discharge valve forming body 138a, the head gasket 138b, and the cylinder head 104 are arranged in this order and fastened by a plurality of through bolts 105. Is done. These form a compressor housing.
Note that mounting portions (102b, 104b) for fixing the compressor housing to the engine protrude from the outer peripheral surface of the front housing 102 and the axial end surface of the cylinder head 104. That is, the variable displacement compressor 100 is attached to the mounting target (engine) via the attachment portions (102b, 104b). 3 indicates a virtual plane including a mounting surface of the mounting portion 102b with the mounting target, and V indicates a plane including the central axis O of the drive shaft 110 and parallel to the virtual plane U. The variable capacity compressor 100 is attached to the mounting target such that the plane V is within a range of, for example, ± 45 ° with respect to the direction of gravity.

  Returning to FIG. 1, a suction passage 104 a is formed in the cylinder head 104 in a straight line across a part of the discharge chamber 142 from the outside toward the suction chamber 141. The suction chamber 141 is connected to the suction side refrigerant circuit of the vehicle air conditioner system via the suction passage 104a. Further, the cylinder head 104 is formed with a discharge passage having a discharge port (not shown). This discharge port is connected to the discharge side refrigerant circuit of the vehicle air conditioner system. Although not shown, a check valve for preventing the backflow of the refrigerant gas from the discharge side refrigerant circuit to the discharge chamber 142 is disposed in the discharge passage. This check valve operates in response to a pressure difference between the upstream side (discharge chamber 142 side) and the downstream side (discharge side refrigerant circuit side), and shuts off the discharge passage when the pressure difference is smaller than a predetermined value. When the pressure difference is larger than the predetermined value, the discharge passage is opened.

The cylinder head 104 is provided with a control valve 300. The control valve 300 is interposed in a pressure supply passage 145 that connects the discharge chamber 142 and the crank chamber 140 to adjust the opening of the pressure supply passage 145, and refrigerant gas (discharge gas) from the discharge chamber 142 to the crank chamber 140 is adjusted. ) Control the amount introduced. The refrigerant gas in the crank chamber 140 flows to the suction chamber 141 via a pressure release passage 147 that connects the crank chamber 140 and the suction chamber 141. The pressure relief passage 147 is provided with an orifice 103 c that regulates the flow rate of the fluid flowing through the pressure relief passage 147. Therefore, the pressure in the crank chamber 140 can be changed by the control valve 300.
The pressure supply passage 145 opens to the crank chamber 140 side at the opening end 145a (see FIG. 3) of the end surface of the cylinder block 101 on the crank chamber side. Further, the pressure release passage 147 and the orifice 103c will be described in detail later.

  More specifically, the control valve 300 adjusts the energization amount to the built-in solenoid based on the external signal, and introduces it into the pressure sensing chamber of the control valve 300 via the pressure introduction passage 146 connected to the suction chamber 141. The discharge capacity is variably controlled so that the pressure of the suction chamber 141 to be a predetermined value, and the pressure supply passage 145 is forcibly opened by shutting off the energization to the solenoid, so that the variable capacity compressor 100 The discharge capacity is controlled to the minimum.

  The angle change operation of the swash plate 111 is caused by the inclination decreasing moment based on the pressure in the crank chamber 140 acting on the surface of the piston 136 on the crank chamber 140 side and the pressure in the cylinder bore 101a acting on the surface of the piston 136 on the cylinder bore 101a side. This is done by breaking the balance with the inclination increasing moment based on it. Therefore, if the pressure in the crank chamber 140 is changed by the control valve 300, the inclination angle of the swash plate 111, that is, the stroke of the piston 136 can be changed, and the discharge capacity of the variable capacity compressor 100 can be variably controlled. .

As described above, the variable displacement compressor 100 according to the present embodiment compresses the refrigerant gas sucked into the cylinder bore 101a from the suction chamber 141 by reciprocating the piston 136 in the cylinder bore 101a by the rotation of the drive shaft 110. The compressed refrigerant gas is discharged to the outside through the discharge chamber 142, the pressure supply passage 145 that connects the discharge chamber 142 and the crank chamber 140 behind the piston 136, the crank chamber 140 and the suction chamber A pressure relief passage 147 communicating with the chamber 141, the flow rate of the pressure relief passage 147 is regulated to a predetermined value, and the opening of the pressure supply passage 145 is adjusted to adjust the pressure in the crank chamber 140. The refrigerant gas discharge capacity can be changed.
The flow rate of the pressure release passage 147 is the flow rate of the refrigerant gas containing the oil mist-like lubricating oil flowing through the pressure release passage 147, that is, the total flow rate of the lubricating oil and the refrigerant gas. This flow rate is simply referred to as “refrigerant gas flow rate”.

  In the present embodiment, the variable displacement compressor 100 includes a rotor 112 fixed to the drive shaft 110 in the crank chamber 140 and the rotor 112 connected to the rotor 112 via the link mechanism 120. And a swash plate 111 variably connected to the central axis, and the piston 136 is reciprocated by the rotational movement of the swash plate 111 to change the tilt angle of the swash plate 111 to thereby change the stroke of the piston 136. This is a so-called swash plate type variable displacement compressor that changes the amount and changes the refrigerant discharge capacity from the cylinder bore 101a.

  Here, lubricating oil is stored in the crank chamber for lubrication between the mechanical portions in the crank chamber 140 and the like. The lubricating oil is agitated by the swash plate 111 or the like, and a part of the lubricating oil scatters in the crank chamber 140 in the form of an oil mist. Thereby, lubrication between the mechanical components in the crank chamber 140 is performed.

The lubricating oil in the crank chamber 140 is desirably stored in the crank chamber as much as possible. However, for example, when the rotational speed of the drive shaft 110 reaches a high speed, if the amount of heat generated by the stirring and shearing of the lubricating oil becomes abnormally high, appropriate lubrication cannot be performed because the viscosity of the lubricating oil decreases. There is a fear.
For this reason, the variable displacement compressor 100 according to the present embodiment promotes the discharge of the lubricating oil scattered in the crank chamber 140 to the suction chamber 141 side at the time of the abnormality as described above, and to the crank chamber 140 at the normal time. The discharge suppressing means 170 for suppressing the discharge of the lubricating oil is provided.

  Hereinafter, the pressure release passage 147, the orifice 103c, and the discharge restraining means 170 will be described in detail with reference to FIGS.

First, the pressure release passage 147 and the orifice 103c will be described.
As shown in FIG. 2, the pressure relief passage 147 is a passage that communicates the crank chamber 140 and the suction chamber 141. In this embodiment, the first center bore 101b1, the introduction passage 101c, the second passage from the crank chamber side. A communication hole (not shown) formed in the center bore 101b2, a suction valve forming body 139a, an orifice 103c formed in the valve plate 103, a discharge valve forming body 138a, and a head gasket 138b. Via. In this way, the pressure release passage 147 is configured to have one path.

The orifice 103c is provided in the pressure release passage 147, and always restricts a part of the pressure release passage 147 so that the flow rate of the refrigerant gas can be regulated by a predetermined value. An appropriate hole diameter (for example, about 1.6 mm). ) To open the valve plate 103.
In the present embodiment, the orifice 103c corresponds to “throttle means” according to the present invention.

The introduction passage 101c is formed in the cylinder block 101 and becomes a part of the crank chamber side pressure release passage on the crank chamber side from the orifice 103c in the pressure release passage 147. The passage cross-sectional area of the introduction passage 101c, each opening area (hole diameter) of each communication hole formed in each gasket and valve forming body (138a, 138b, 139a) is larger than the opening area (hole diameter) of the orifice 103c. An opening is formed at Therefore, the flow rate of the refrigerant gas flowing through the pressure release passage 147 is regulated by the orifice 103 c having the smallest opening area in the whole pressure release passage 147.
In the present embodiment, the introduction passage 101c corresponds to “a part of the crank chamber side pressure release passage” according to the present invention.

In the present embodiment, the introduction passage 101c is configured to open toward the crank chamber 140 at the bottom wall 101b12 (the bottom of the recess) of the first center bore 101b1.
Specifically, the introduction passage 101c extends from the bottom wall 101b12 of the first center bore 101b1 toward the suction chamber 141 side in parallel with the central axis O of the drive shaft 110, and the bottom wall of the second center bore 101b2. 101b22 is opened, and the first center bore 101b1 and the second center bore 101b2 are formed to communicate with each other. One end (first center bore side) of the introduction passage 101c is a part of the bottom wall 101b12 that protrudes toward the crank chamber 140 and opens toward the first center bore 101b1.

  In the present embodiment, the introduction passage 101c opens at the bottom wall 101b12 of the first center bore 101b1 and below the center axis O of the drive shaft 110 in the gravity direction. Specifically, the introduction passage 101c is communicated with the first center bore 101b1 below the center axis of the drive shaft 110 in the gravitational direction with the variable displacement compressor 100 attached to the mounting target (engine).

Next, the discharge suppression means 170 will be described.
The discharge suppression means 170 is disposed in the crank chamber side pressure release passage closer to the crank chamber 140 than the orifice 103c in the one-way pressure release passage 147, and the lubricant scattered in the crank chamber 140 is directed to the suction chamber 141 side. When there is a later-described restraining portion 170b that restrains the discharge, and the restraining portion 170b is restraining, the opening area of the crank chamber side pressure release passage at the location where the restraining portion 170b is arranged is defined as the flow path cross-sectional area of the orifice 103c (for example, When the temperature of the crank chamber 140 is equal to or higher than a predetermined temperature, the opening area of the crank chamber side pressure release passage is increased at the location where the suppressing portion 170b is disposed. It is configured so that the suppression can be released. The discharge suppressing means 170 suppresses the discharge of the lubricating oil scattered in the crank chamber 141, and the amount of the lubricating oil discharged to the suction chamber 141 through the pressure release passage 147 together with the refrigerant gas in the crank chamber 140. Decrease.

  In the present embodiment, the crank chamber side pressure release passage is a passage that passes through the second center bore 101b2, the introduction passage 101c, and the first center bore 101b1. A discharge suppression hole 172, which will be described later, is set smaller than the passage sectional area of the introduction passage 101c and larger than the passage sectional area of the orifice 103c.

The temperature of the crank chamber 140 refers to the housing temperature of the housing members (front housing 102, cylinder block 101) forming the crank chamber 140 or the fluid temperature (refrigerant gas, lubricating oil) in the region where the pressure of the crank chamber 140 acts. ). The discharge suppression means 170 operates in response to at least one of the housing temperature and the fluid temperature.
The predetermined temperature is higher than the temperature of the crank chamber 140 when the rotational speed of the drive shaft 110 is in the range of the normal rotational speed (from the idling equivalent rotational speed of the engine of the vehicle as an external drive source to about 5000 rpm), and the variable capacity compressor It is set below the limit temperature (about 150 ° C.) at which 100 operates properly.

  In the present embodiment, the discharge suppression unit 170 includes a temperature sensing unit 170a and a suppression unit 170b as shown in FIGS. The temperature sensing unit 170a can detect the temperature of the crank chamber 140 and can be displaced in the release direction of the suppression according to the detected temperature. The suppression unit 170b has a discharge suppression hole 172 that is provided at the displacement end of the temperature sensing unit 140 and opens larger than the flow path cross-sectional area of the orifice 103c. Then, the discharge suppression unit 170 includes the suppression unit 170b in the crank chamber side pressure release passage, suppresses the discharge of the lubricating oil through the discharge suppression hole 172, and when the detected temperature is equal to or higher than a predetermined temperature, the suppression unit The configuration is such that the suppression of the discharge of the lubricating oil is released by displacing 170b in the release direction of the suppression.

  Specifically, the temperature sensing part 170a is arranged on the crank chamber side wall surface of the formed body that forms part of the cylinder block 101, that is, the crank chamber side pressure release passage (introduction passage 101c). In addition, the suppression unit 170b provided at the displacement end of the temperature sensing unit 170a contacts and separates from the cylinder block 101 according to the temperature sensed by the temperature sensing unit 170a.

More specifically, as shown in FIGS. 4 and 5, the discharge suppression means 170 is disposed on the bottom wall 101b12 (bottom portion of the recess) of the first center bore 101b1, and the temperature sensing portion 170a and the suppression portion 170b are integrated. It consists of the formed plate-shaped temperature-sensitive member. The temperature sensing unit 170a operates in response to the higher temperature of the temperature of the bottom wall 101b12 of the first center bore 101b1 or the fluid temperature (refrigerant gas or lubricating oil) in the crank chamber 140 as the housing temperature.
The discharge suppression means 170 has one end side (temperature sensing portion side) in surface contact with the bottom wall 101b12 of the first center bore 101b1 and is fixed by the fixing member 160, and the other end side (suppression portion 170b side) is the crank of the introduction passage 101c. It is configured to abut (FIG. 4) and separate (FIG. 5) on the opening end on the chamber 140 side. The other end side of the plate-like discharge suppression means 170 has a convex portion protruding toward the crank chamber as the suppression portion 170b. The discharge suppression hole 172 passes through the convex portion and is formed to face the open end of the introduction passage 101c when the discharge of the lubricating oil is suppressed. The discharge suppression hole 172 suppresses the discharge of the lubricating oil.

  The discharge suppression means 170 is made of, for example, a reversal operation type bimetal that performs a reversal operation at a predetermined temperature. When the temperature of the crank chamber 140 becomes equal to or higher than a preset first temperature, the suppression unit 170b is moved in the suppression release direction. When the temperature of the crank chamber 140 falls below a second temperature that is lower than the preset first temperature as appropriate, the suppression portion 170b is brought into contact with the opening end of the introduction passage 101c. This first temperature corresponds to the aforementioned predetermined temperature (a temperature higher than the temperature of the crank chamber 140 at the normal rotational speed and lower than the limit temperature). That is, in a normal use state, the discharge suppression unit 170 does not perform a reversing operation and keeps the suppression unit 170b in contact with the opening end of the introduction passage 101c. For example, the first temperature is set within a range of 110 ° C. to 140 ° C., and the second temperature is set to a temperature lower by about 15 ° C. to 20 ° C. than the first temperature.

  Further, the discharge restraining means 170 has a bent portion 171 for bending the intermediate portion in the longitudinal direction in the displacement direction (vertical direction in FIG. 4) to promote the reversing operation. The bending portion 171 can perform the reversing operation more reliably.

  In the present embodiment, the discharge suppressing means 170 is disposed on the bottom wall 101b12 of the first center bore 101b1. The depth of the first center bore 101b1 is defined so that the tip of the restraining portion 170b does not protrude toward the crank chamber 140 when the discharge restraining means 170 is reversed and displaced maximum.

  Next, the operation and action of the variable displacement compressor 100 of the present embodiment will be described with reference to FIGS. In the description, it is assumed that the lubricating oil is stored in the crank chamber 140.

  First, the temperature in the crank chamber 140 is equal to or lower than the second temperature. At this time, a part of the high-pressure refrigerant gas (discharge gas) in the discharge chamber 142 passes through the pressure supply passage 145 by the discharge volume change control by the control valve 300. The high pressure refrigerant gas (blow-by gas) flows into the crank chamber 140 through the gap between the cylinder bore 101a and the piston 136 by the compression process by the piston 136. The operation | movement at the time of suppression of discharge | emission and its effect | action are demonstrated.

Since the temperature of the crank chamber 140 is equal to or lower than the second temperature, the discharge restraining means 170 keeps the restraining portion 170b in contact with the opening end of the introduction passage 101c as shown in FIG. The opening of the introduction passage 101c is minimized. At this time, when a high-pressure refrigerant gas (discharge gas, blow-by gas) flows into the crank chamber 140, the lubricating oil scattered in the crank chamber 140 is released along with the refrigerant gas along the flow of the high-pressure refrigerant gas. An attempt is made to flow to the suction chamber 141 via 147. However, since the opening degree of the introduction passage 101 c is set to the minimum by the discharge suppression hole 172, the discharge of the lubricating oil to the suction chamber 141 is suppressed by the discharge suppression hole 172. Thereby, the amount of lubricating oil flowing out from the suction chamber 141 to the external refrigerant circuit via the discharge chamber 142 can be reduced, that is, OCR can be reduced.
Specifically, the lubricating oil (oil mist particles) scattered in the crank chamber 140 includes particles that directly merge with the flow of the refrigerant gas and pass through the discharge suppression hole 172. There are particles that slowly move along the surface of the portion 170b toward the discharge suppression hole 172, merge with the refrigerant gas flow and pass through the discharge suppression hole 172, particles that collide with the surface of the discharge suppression portion 170b and bounce off. As described above, the merging of particles (lubricating oil) into the refrigerant gas flow can be suppressed by reducing the moving speed of the particles toward the refrigerant gas flow or rebounding the particles by the suppressing unit 170b. . Therefore, by suppressing the opening degree of the introduction passage 101c by the suppressing portion 170b, the discharge of the lubricating oil to the suction chamber 141 can be suppressed as compared with the case where the opening degree of the introduction passage 101c is increased. it can.

  Next, it is assumed that the rotational speed of the drive shaft 110 further increases beyond the normal rotational speed, and the temperature in the crank chamber 140 becomes equal to or higher than the first temperature. Assuming that the refrigerant gas is flowing into the crank chamber 140, the operation for releasing suppression and its action will be described.

When the temperature of the crank chamber 140 becomes equal to or higher than the first temperature, the discharge suppression means 170 moves the suppression portion 170b toward the crank chamber 140 as shown in FIG. The release of the lubricating oil by the discharge suppressing hole 172 is released, and the opening area of the introduction passage 101c at the place where the suppressing portion 170b is disposed is maximized. When the high-pressure refrigerant gas flows into the crank chamber 140, the lubricating oil scattered in the crank chamber 140 flows along with the flow of the high-pressure refrigerant gas into the suction chamber 141 along with the refrigerant gas via the pressure release passage 147. Try to. At this time, since the opening degree of the introduction passage 101c is set to the maximum, the discharge of the lubricating oil to the suction chamber 141 is promoted. As a result, the amount of lubricating oil in the crank chamber 140 is smaller than that in the case of the normal rotational speed, the amount of heat generated by the stirring of the lubricating oil by rotating parts such as the swash plate 111 is reduced, and the temperature of the crank chamber 140 is increased. It is suppressed.
On the other hand, the lubricating oil discharged to the suction chamber 141 flows out to the external refrigerant circuit via the cylinder bore 101a and the discharge chamber 142. Then, this lubricating oil is cooled by the evaporator of the external refrigerant circuit, returns again to the suction port 104a and the suction chamber 141, is taken into the cylinder bore 101a, and is returned to the crank chamber 140 along with blow-by gas and the like. Lubrication between each mechanism part is performed effectively.
When the temperature of the crank chamber 140 becomes equal to or lower than the second temperature due to, for example, the temperature rise of the crank chamber 140 being suppressed by the recirculation of the lubricating oil cooled by the evaporator, the suppressing portion 170b again opens the introduction passage 101c. Contact with the end portion prevents the lubricating oil from being discharged again. This is repeated in response to the temperature of the crank chamber 140. In this manner, the discharge suppression unit 170 is a suppression unit capable of reversible operation that can perform the suppression operation again after the suppression is released.
Although the amount of lubricating oil flowing out from the suction chamber 141 to the external refrigerant circuit through the discharge chamber 142 increases, it is a transient increase when it is abnormally higher than the normal rotation speed, so that the cooling performance of the air conditioning system is substantially reduced. The effects are negligible.

  Here, the discharge suppression hole 172 is formed with an opening area that is smaller than the passage sectional area of the introduction passage 101c and larger than the passage sectional area of the orifice 103c. Even when this discharge is suppressed, the flow rate restriction by the orifice 103c is not affected. That is, even if the discharge suppressing means 170 operates and the suppressing portion 170b repeatedly contacts and separates from the opening end portion of the introduction passage 101c, the orifice 103c is always the restriction portion for the refrigerant gas flow rate in the entire pressure release passage 147. Thus, the pressure adjustment of the crank chamber 140 by the control valve 300 is not affected. Therefore, the discharge capacity control by the control valve 300 can be stably performed regardless of the operation of the discharge suppression unit 170.

According to the variable displacement compressor 100 of this embodiment, the crank chamber side pressure release passage on the crank chamber 140 side from the orifice 103c in the pressure release passage 147 consisting of one path connecting the crank chamber 140 and the suction chamber 141. The amount of the lubricating oil scattered in the crank chamber 140 is discharged through the crank chamber side pressure release passage together with the refrigerant gas flowing into the crank chamber 140 by the discharge suppressing means 170 having the suppressing portion 170b disposed in the cylinder. Can be reduced. According to the variable capacity compressor 100, the opening area of the crank chamber side pressure release passage at the location where the suppressing portion 170b is arranged is set larger than the flow passage cross-sectional area of the orifice 103c in the crank chamber 140. By suppressing the discharge of the scattered lubricating oil to the suction chamber 141 side and releasing the suppression of the discharge of the lubricating oil to the suction chamber 141 side when the temperature of the crank chamber 140 is equal to or higher than a predetermined temperature, the lubricating oil is released. Can be promoted to the suction chamber 141 side, and at all times, that is, after the suppression is released and when the suppression is being performed, the refrigerant gas in the pressure release passage 147 is released by the orifice 103c. The flow rate can be regulated by a predetermined value. Therefore, the refrigerant gas flow rate in the pressure release passage 147 can always be regulated to properly adjust the pressure in the crank chamber 140 regardless of whether or not the discharge suppression means 170 releases the discharge, and the crank chamber 140 and the suction chamber can be simply adjusted. The pressure release passage 147 that communicates with the pressure release passage 141 can be used as a lubricant discharge passage, and it is not necessary to form a separate lubricant discharge passage separately from the pressure release passage 147.
In this way, it is possible to provide a variable displacement compressor that can facilitate the discharge of the lubricating oil in the crank chamber into the suction chamber at a high temperature with a simple structure without affecting the pressure adjustment of the crank chamber. .

  Further, in the present embodiment, since the discharge suppression hole 172 is formed through a convex portion protruding toward the crank chamber side, the lubricating oil adhered to the bottom wall 101b12 and the peripheral wall 101b11 of the first center bore 101b1 when discharging is suppressed. Becomes difficult to circulate through the discharge suppression hole 172. Thereby, the discharge suppression by the discharge suppression means 170 becomes effective.

Further, in the present embodiment, the temperature sensing part 170a is disposed on the side wall surface of the crank chamber of the cylinder block 101, the suppression part 170b is provided at the displacement end of the temperature sensing part 170a, and according to the sensed temperature of the temperature sensing part 170a. In this configuration, the suppressing portion 170b is brought into contact with and separated from the cylinder block 101c. In this way, the discharge suppression means 170 (the temperature sensing unit 170a and the suppression unit 170b) need only be disposed on the crank chamber side wall surface of the cylinder block 101, and the discharge suppression and release of the lubricating oil can be constructed with a simple structure. Can do.
The discharge suppressing means 170 is not limited to the configuration arranged on the side wall surface of the crank chamber of the cylinder block 101. For example, the discharge suppressing means 170 may be provided in the intermediate portion of the introduction passage 101c. A temperature-sensitive portion that can be displaced in the release direction of the suppression of lubricant discharge according to the temperature is provided, and the suppression portion is provided at the displacement end of the temperature-sensitive portion, and the suppression portion is opened larger than the cross-sectional area of the flow path of the throttle means. What is necessary is just the structure which has a discharge | emission suppression hole which suppresses, suppresses via a discharge | emission suppression hole, and displaces a suppression part in the cancellation | release direction of suppression, when sensed temperature is more than predetermined temperature. Further, the present invention is not limited to the configuration in which the suppression portion is provided with the discharge suppression hole, and may be configured as in the second embodiment described below.

  FIG. 6 is a view for explaining the discharge suppression means 170 ′ of the variable displacement compressor 100 according to the second embodiment of the present invention, and shows a state during discharge suppression in a partial cross-sectional view in the same cross section as FIG. It is the figure shown by. FIG. 7 is a top view of a later-described protrusion 101d as seen from the direction of arrow B in FIG. Only the shape of the opening part by the side of the crank chamber of the suppression part and the introduction channel | path 101c differs from 1st Embodiment. The same elements as those of the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions will be described. Since the discharge suppression and its release operation are the same as those in the first embodiment, the description thereof is omitted.

  In the present embodiment, the cylinder block 101 has a protruding portion 101d formed by protruding the peripheral edge of the passage opening of the introduction passage 101c on the side wall surface of the crank chamber, and the protruding portion 101d has a notch groove 101e at the end. The groove cross-sectional area of the notch groove 101e is configured to be larger than the flow path cross-sectional area of the orifice 103c.

In the present embodiment, the discharge suppression means 170 ′ is provided at the temperature sensing part 170a and the displacement end of the temperature sensing part 170a, and with respect to the projecting end part 101f of the projecting part 101d according to the sensed temperature of the temperature sensing part 170a. A restraining portion 170b ′ that comes in contact with and separates from the projecting end portion (projecting end surface) 101f so that only the notch groove 101e can be opened to the crank chamber 140 side. When the detected temperature is equal to or higher than a predetermined temperature (first temperature), the suppression unit 170b ′ is displaced in the release direction of the suppression to release the suppression.
The discharge restraining means 170 ′ is a simple plate-like temperature sensing member in which the temperature sensing portion 170a and the restraining portion 170b ′ are integrally formed. Unlike the first embodiment, the suppressing portion 170b ′ is formed in a plate shape.

According to the variable displacement compressor 100 of this embodiment, as in the first embodiment, the intake air for the lubricating oil in the crank chamber is transferred to the crank chamber at a high temperature with a simple structure without affecting the pressure adjustment of the crank chamber. Can be provided.
Further, in the present embodiment, by devising the shape of the opening end portion (passage opening peripheral portion) on the crank chamber side of the introduction passage 101c, it is not necessary to form the discharge suppression hole in the suppression portion 170b, and the discharge suppression means The shape can be simplified.

  In the first embodiment and the second embodiment, the discharge restraining means 170 and 170 'are disposed on the bottom wall 101b12 of the first center bore 101b1. Therefore, it is possible to easily prevent interference between the discharge suppression unit 170 and the swash plate 111 in the crank chamber 140. The introduction passage 101c is configured to open toward the crank chamber 140 at the bottom wall 101b12 (bottom portion of the recess) of the first center bore 101b1. As a result, the introduction passage 101c is a passage that simply communicates the first center bore 101b1 and the second center bore 101b2 in a straight line, so that passage formation is easy.

  In each embodiment, a plurality of cylinder bores 101 c are arranged in the circumferential direction in the cylinder block 101. And the 1st center bore 101b1 in which the discharge | emission suppression means 170 is arrange | positioned is provided in the center part which the drive shaft 110 in the cylinder block 101 penetrates so that it may be surrounded by each cylinder bore 101a, and is formed in concave shape. Therefore, this is an oil-poor region in which the lubricating oil scattered in the crank chamber 140 does not easily flow. Therefore, it becomes difficult for lubricating oil attached to the bottom wall 101b12 and the peripheral wall 101b11 of the first center bore 101b1 to flow through the discharge suppression hole 172 and the notch groove 101e when discharging is suppressed. As a result, the discharge suppression by the discharge suppression means 170, 170 'becomes more effective.

  Further, in each embodiment, the drive shaft 110 is supported through the bottom wall 101b12 of the first center bore 101b1 across the center in the crank chamber 140, the introduction passage 101c is the bottom wall 101b12, and the drive shaft 110 The center axis line O is opened downward in the gravitational direction toward the crank chamber 140 side. Here, at the time of high speed rotation, the amount of lubricating oil entering the first center bore 101b1 is increased by the stirring compared to the case of the normal rotation speed, and the introduction passage 101c is opened below the center axis O of the drive shaft 110 in the gravity direction. Is done. Therefore, for example, the amount of lubricating oil that adheres to the bottom wall 101b12 etc. and flows downward along the bottom wall 101b12 in the direction of gravity and reaches the opening end of the introduction passage 101c is greater in the direction of gravity from the center axis O in the introduction passage 101c. Compared to the case of opening on the upper side, the number increases. As a result, the lubricating oil is easily discharged through the introduction passage 101c. As a result, when the suppression of the discharge is released, the discharge of the lubricating oil is more effectively promoted.

  In each embodiment, the discharge suppression means 170, 170 'is made of bimetal. The reverse operation type bimetal does not displace much at a temperature lower than the reversal temperature, and greatly displaces when the reversal temperature is exceeded. Therefore, normally, the discharge of the lubricating oil is reliably suppressed, and the temperature of the crank chamber 140 is the first temperature. When it becomes above, the suppression part 170b can be instantaneously separated from the opening edge part of the introduction channel | path 101c, and suppression of discharge | release can be cancelled | released rapidly.

  Although the contents of the present invention have been specifically described with reference to the preferred embodiments, those skilled in the art can further adopt various modifications based on the basic technical idea and teachings of the present invention. Is self-explanatory.

  For example, in each embodiment, after canceling the suppression of the exhaust, when the temperature of the crank chamber 140 becomes a second temperature lower than the first temperature by about 15 ° C. to 20 ° C., the configuration is configured to suppress the exhaust again. However, the present invention is not limited to this, and it may be configured to suppress discharge again at least when the temperature becomes lower than the first temperature.

  Moreover, in each embodiment, although the discharge | emission suppression means 170,170 'was demonstrated by the structure by which a temperature sensing part and a suppression part are integrally formed, not only this but a temperature sensing part and a suppression part are separate. It may be configured. Moreover, although the discharge | emission suppression means (temperature-sensitive member) shall consist of bimetals, it is not restricted to this, It is good also as what consists of other temperature-sensitive members, such as a shape memory alloy.

  Furthermore, in each embodiment, the opening end position on the crank chamber side of the introduction passage 101c is set to the lower side in the gravity direction of the center axis O of the drive shaft 110 in the first center bore 101b1, but is not limited thereto. There may be. In addition, the suction chamber 141 is disposed at the center of the cylinder head 104, and the discharge chamber 142 is formed so as to surround the suction chamber 141 in an annular shape, but the present invention is not limited thereto, and the discharge chamber 142 is disposed at the center. The suction chamber 141 may be formed so as to surround the discharge chamber 142 in an annular shape. The throttle means is the orifice 103c having a fixed opening, but is not limited thereto, and may be a throttle or valve mechanism having a variable opening.

  In each of the embodiments, a swash plate type variable displacement compressor has been described as an example. However, the present invention is not limited to a swash plate type variable displacement compressor, and for example, a so-called oscillating plate variable displacement compressor. It can also be applied. In the case of an oscillating plate type variable displacement compressor, an oscillating plate is provided as means for converting the rotational motion of the swash plate 111 into the reciprocating motion of the piston 136. Further, the variable capacity compressor according to the present invention is not limited to a clutchless compressor but can be applied to a compressor equipped with an electromagnetic clutch or the like.

  By the way, in the variable displacement compressor described in Patent Document 1, the connection passage to the crank chamber side of the pressure release passage is branched into two paths, and the crank chamber side of one of the two paths is on the crank chamber side. Opening and closing means is provided at the opening end of the cylinder, and the opening end is disposed in the vicinity of the peripheral wall of the crank chamber. However, since the lubricating oil adhering to the drive shaft, the swash plate, and the like is an oil-rich area in the vicinity of the peripheral wall due to the centrifugal force, the area near the peripheral wall is opened by opening and closing means. There is a risk that the lubricating oil will be excessively discharged from the passage in the vicinity of the peripheral wall. As a result, there is a possibility of causing insufficient lubrication of each sliding portion in the crank chamber. Further, the shape of the passage in the vicinity of the peripheral wall is complicated to reach the junction with the other passage. In order to solve this problem, a variable capacity compressor as a reference example of the present invention will be described below.

  A reference example of a variable capacity compressor according to a reference invention of the present invention will be described with reference to FIGS. The variable capacity compressor 100 ′ according to this reference example uses the configuration of the variable capacity compressor 100 according to the first embodiment (FIGS. 1 to 6) as a basic configuration, and the first embodiment described above. The same elements as those in the embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions will be described. Also in this reference example, various modifications described in the first embodiment can be adopted.

FIG. 8 is a longitudinal sectional view of the variable capacity compressor 100 ′ of this reference example.
The variable capacity compressor 100 ′ of the reference invention is configured to reciprocate a cylinder block in which a center bore and a plurality of cylinder bores arranged so as to surround the center bore are partitioned, and a piston in each cylinder bore by rotation of a drive shaft. A compression mechanism that compresses the refrigerant gas sucked into the cylinder bore from the suction chamber and discharges the refrigerant gas to the outside through the discharge chamber, a pressure supply passage that connects the discharge chamber and the crank chamber behind the piston, A pressure relief passage communicating the crank chamber and the suction chamber, and a throttle means provided in the pressure relief passage, and capable of constantly regulating the refrigerant gas flow rate in the pressure relief passage with the predetermined value; A variable capacity type that regulates the pressure of the crank chamber and changes the discharge capacity of the refrigerant by regulating the flow rate of the pressure release passage to a predetermined value and adjusting the opening of the pressure supply passage In the compressor, the crank chamber side pressure release passage closer to the crank chamber than the throttling means among the pressure release passages has a first introduction passage having one end opened to the crank chamber side, and one end at a different path from the first introduction passage. A second introduction passage that opens to the crank chamber side, and a merging portion that joins the other end of the first introduction passage and the other end of the second introduction passage, and the center bore opens to the crank chamber side. An opening / closing means is provided in the first introduction passage, the second center bore forms the merging portion, and the first introduction hole has a first center bore and a second center bore that opens to the suction chamber side. Of the passage and the second introduction passage, at least the first introduction passage is configured to open to the first center bore. Hereinafter, this configuration is referred to as reference configuration 1 that forms the basic configuration of the reference invention.

  As shown in FIGS. 9 and 10, in the variable displacement compressor 100 ′ of the present reference example, the crank chamber side pressure release passage is a separate route from the aforementioned introduction passage (hereinafter referred to as the first introduction passage) 101c1, The first introduction passage 101c1 includes a second introduction passage 101c2 having one end opened to the crank chamber side, and a joining portion where the other end of the first introduction passage 101c1 and the other end of the second introduction passage 101c2 join. An opening / closing means is disposed on the top. As the opening / closing means, the discharge suppressing means 170 '(hereinafter referred to as opening / closing means 170') made of the plate-like temperature-sensitive member of the second embodiment (FIG. 7) is applied.

  Further, as shown in FIG. 9, the second center bore 101b2 forms the junction, and the first introduction passage 101c1 in which at least the opening / closing means 170 'is disposed opens to the first center bore 101b1. For example, when the opening / closing means 170 ′ is operating at the normal rotational speed, as shown in FIG. 11, the opening end on the crank chamber side of the first introduction passage 101 c is fully closed, and the rotational speed is equal to the normal rotational speed. When the temperature of the crank chamber 140 rises beyond the first temperature and exceeds the first temperature, as shown in FIG. 12, the opening end of the first introduction passage 101c1 is fully opened and the temperature is lowered, for example, the second temperature. When it becomes below, it is fully closed again as shown in FIG.

  According to the variable displacement compressor 100 ′ of the present reference example, the first introduction passage 101c1 in which the opening / closing means 170 ′ is disposed opens into the first center bore 101b1 that is an oil-poor region. Even if the first introduction passage 101 c 1 is opened by 170 ′, excessive outflow of the lubricating oil scattered in the crank chamber 140 is suppressed, and there is no possibility that the lubricating oil stored in the crank chamber 140 is depleted. Further, since the first introduction passage 101c1 in which the opening / closing means 170 'is disposed needs only to connect the first center bore 101b1 and the second center bore 101b2 in a straight line, the passage formation is easy.

In the reference configuration 1, in the present reference example, the first center bore 101b1 further includes a peripheral wall 101b11 that forms a wall of each cylinder bore 101a on the crank chamber side wall surface of the cylinder block 101, and a bottom wall 101b12 that faces the crank chamber 140. The first introduction passage 101c1 extends substantially parallel to the drive shaft 110, and has one end opened in the bottom wall 101b12 and the other end opened in the second center bore 101b2, 170 ′ is a temperature-sensitive member whose one end is in surface contact with the bottom wall 101b12 of the first center bore 101b1 and fixed, and the other end is a temperature-sensitive member that closes the opening end of the first introduction passage 101c1 on the crank chamber side. When the temperature is equal to or higher than a predetermined temperature, the other end side is displaced toward the crank chamber side to open the open end (hereinafter referred to as reference). (Consideration 2).
According to the reference configuration 2, since the first introduction passage 101c1 extends substantially parallel to the drive shaft 110, the passage configuration becomes easier. The opening / closing means 170 ′ is fixed in surface contact with the bottom wall 101b12 of the first center bore 101b1 and faces the crank chamber 140, so that the temperature of the bottom wall 101b12 of the first center bore 101b1 and the fluid temperature in the crank chamber are It operates in response to the higher temperature, which contributes to improved reliability.

In addition to the above-described reference configuration 2, in the present reference example, the first introduction passage 101c1 is disposed and formed below the second introduction passage 101c2 in the direction of gravity, and the opening / closing means 170 ′ is connected to the crank of the first introduction passage 101c1. When the opening end on the chamber 140 side is closed, the first introduction passage 101c1 serves as a storage space for storing lubricating oil flowing into the second center bore 101b2 from the first center bore 101b1 (hereinafter referred to as reference configuration 3). including.
According to the reference configuration 3, even if the lubricating oil flows toward the second center bore 101b2 through the second introduction passage 101c2 that is on the upper side in the gravity direction, the second center bore 101b2 becomes the lubricating oil reservoir. In addition, since the first introduction passage 101c1 whose opening end on the crank chamber 140 side is closed can be caused to function as a lubricating oil reservoir, the discharge of the lubricating oil into the suction chamber 141 can be more effectively suppressed. . However, the present invention is not limited to this, and the reference configuration 1 described above may be simply a reference configuration including the reference configuration 3.

Further, in addition to the above reference configurations 2 and 3, in this reference example, the second introduction passage 101c2 also includes a configuration (hereinafter referred to as a reference configuration 4) that opens to the first center bore 101b1.
According to the reference configuration 4, since only two passages are formed between the first center bore 101b1 and the second center bore 101b2, passage formation is easy, and the first introduction is performed by the opening / closing means 170 ′. When the passage 101c1 is closed, the outflow of lubricating oil to the refrigerant circuit is effectively suppressed, and the refrigerant performance can be improved. In addition, not only this but in each said reference structure, it is good also as a reference structure only including the reference structure 4. FIG.

Furthermore, in addition to the above reference configurations 2, 3 and 4, in the present reference example, the first introduction passage 101c1 and the second introduction passage 101c2 each extend substantially parallel to the drive shaft 110, and have one end thereof. It includes a configuration that opens to the bottom wall 101b12 and the other end opens to the second center bore 101b2 (hereinafter referred to as reference configuration 5).
According to the reference configuration 5, it is much easier to form two paths. In addition, not only this but in each said reference structure, it is good also as a reference structure containing the reference structure 5 only.

  Here, in the present reference example, as in the reference configuration 5, the second introduction passage 101c2 extends substantially parallel to the drive shaft 110, and one end opens to the bottom wall 101b12 and the other end is the second center bore. However, the present invention is not limited to this. As shown in FIG. 13, the opening is formed inside the drive shaft 110 and the opening on one end side faces the peripheral wall 101b11 side of the first center bore 101b1 ( Hereinafter, it may be referred to as reference configuration 6). In addition, not only this but each reference structure which does not include the reference structure 5 is good also as a reference structure including the reference structure 6 only.

Specifically, in the above reference configuration 6, as shown in FIG. 13, the second introduction passage 101c2 is a communication that extends in the direction of the central axis O of the drive shaft 110 from one end surface of the drive unit 110 to the inside. The hole 110a includes a communication hole 110b extending from the end of the communication hole 110a toward the peripheral wall 101b11 of the first center bore 101b1 in a direction orthogonal to the central axis O, and the opening of the communication hole 110b is the first center bore 101b1. The opening of the communication hole 110a is configured to communicate with the second center bore 101b2 via the through hole of the thrust plate 132 and the adjusting screw 135.
According to this reference configuration 6, the length of the second introduction passage 101c2 in the direction of the central axis O can be shortened, and it is only necessary to form the passage from the shaft end and the outer periphery of the drive shaft 110. Is easy. In addition, the opening of the communication hole 110b faces the peripheral wall 101b11 of the first center bore 101b1, is located in the oil-filled first center bore 101b1, and the opening rotates together with the drive shaft 110, so that the second introduction passage 101c2 The outflow of the lubricating oil to the second center bore 101b2 can be remarkably suppressed, and the cooling performance of the air conditioning system when the first introduction passage 101c1 is closed by the first opening / closing means 170 ′ can be further improved.

  In this reference example, the pressure supply passage 145 and the pressure release passage 147 are formed independently of each other. However, the present invention is not limited to this, and as shown in FIG. 14, the pressure supply passage 145 and the pressure release passage are provided. 147 may have a common part. That is, in each of the reference configurations described above, the second center bore 101b2 and the second introduction passage 101c2 may be configured to serve as part of the pressure supply passage 145 (hereinafter referred to as reference configuration 7). FIG. 14 differs from FIG. 13 only in the pressure supply passage 145.

  In the reference configuration 7, specifically, as shown in FIG. 14, the pressure supply passage 145 opens from the discharge chamber 142 via the control valve 300 to the second center bore 101b2 via the opening end 145b, The center bore 101b2 reaches the crank chamber 140 via the second introduction passage 101c2 and the first center bore 101b1. In this manner, a region from the second center bore 101b2 to the first center bore 101b1 serves as a shared portion of the pressure supply passage 145 and the pressure release passage 147. The second center bore 101b2 serves as a joining portion between the first introduction passage 101c1 and the second introduction passage 101c2, and also serves as a joining portion with the pressure supply passage 145.

In the reference configuration 7, the flow of the refrigerant in the pressure release passage 147 when the control valve 300 is closed is the same as the reference configuration 6 shown in FIG.
When the control valve 300 changes from the closed state to the open state, a high-pressure refrigerant gas flow from the discharge chamber 142 toward the crank chamber 140 is generated. This refrigerant gas flows into the crank chamber 140 via the second center bore 101b2, the second introduction passage 101c2, and the first center bore 101b1, but since the refrigerant gas contains lubricating oil, it follows the jet of refrigerant gas. As a result, the lubricating oil scatters and lubricates between the sliding portions in the crank chamber 140. Since the communication hole 110b is opened to face the peripheral wall 101b11 of the first center bore 101b1, the lubricating oil is injected toward the peripheral wall 101b11 together with the refrigerant gas from the opening of the communication hole 110b. The lubricating oil that has collided with the peripheral wall 101b11 scatters toward the crank chamber 140, and contributes to lubrication of the sliding surface between the swash plate 111 and the shoe 137 on the compression side in particular.
When the variable displacement compressor 100 ′ is in the discharge capacity control state and the opening degree of the control valve 300 is an arbitrary opening degree between fully closed and fully opened, the amount of refrigerant defined by the opening degree Since the gas is introduced into the second center bore 101b2, a bidirectional flow is generated in the common passage of the pressure supply passage 145 and the introduction passage 147 in accordance with the amount of the introduced refrigerant gas. The discharge capacity can be variably controlled by changing the pressure of the piston 136 and changing the stroke of the piston 136.
According to the reference configuration 7, it is very easy to form the entire pressure supply passage and the pressure release passage.

100 ········ variable displacement compressor 101a ··· cylinder bore 103c ··· throttle means (orifice)
170 ··· Discharge suppression means 170a · · · Temperature sensing portions 170b and 170b '··· Control portion 172 ··· Discharge suppression hole 101c ··· Crank chamber side pressure release passage Part of (introductory passage)
101 ······· Formed body (cylinder block)
101d... Projection 101f... Projection end 101e... Notch groove 101b1... Recess (first center bore)
101b12 ... Bottom (bottom wall)
110 ······ Drive shaft 111 ··· Swash plate 136 ··· Piston 140 ··· Crank chamber 141 ··· Suction chamber 142 ··· · Discharge chamber 145 ··· Pressure supply passage 147 ··· Pressure release passage O ··· Center axis

Claims (9)

A compression mechanism that reciprocates the piston in the cylinder bore by rotation of the drive shaft, compresses the refrigerant gas sucked into the cylinder bore from the suction chamber, and discharges the refrigerant gas to the outside through the discharge chamber;
A pressure supply passage communicating the discharge chamber and the crank chamber behind the piston;
A pressure release passage communicating the crank chamber and the suction chamber;
A variable displacement type that regulates the pressure of the crank chamber and changes the discharge capacity of the refrigerant by regulating the flow rate of the pressure release passage to a predetermined value and adjusting the opening of the pressure supply passage In the compressor,
The pressure relief passage consists of one path,
Throttle means provided in the pressure relief passage;
A discharge restraining means having a restraining portion disposed in the crank chamber side pressure relief passage on the crank chamber side from the throttling means in the pressure relief passage and restraining the discharge of the lubricating oil in the crank chamber to the suction chamber side; When the suppression is performed, the opening area of the crank chamber side pressure release passage at the location where the suppression portion is disposed is set larger than the flow passage cross-sectional area of the throttle means, and the temperature of the crank chamber is equal to or higher than a predetermined temperature. A discharge suppression means configured to increase the opening area so as to release the suppression; and
A variable displacement compressor configured with The discharge suppression means is
A temperature sensing part that senses the temperature of the crank chamber and can be displaced in the release direction of the suppression according to the sensed temperature;
The suppression unit is provided at the displacement end of the temperature sensing unit, and the suppression unit has a discharge suppression hole that is opened larger than the flow path cross-sectional area of the throttling means,
2. The configuration according to claim 1, wherein the suppression is performed via the discharge suppression hole, and when the sensed temperature is equal to or higher than the predetermined temperature, the suppression unit is displaced in a release direction of the suppression to release the suppression. The variable capacity compressor described. The temperature sensing portion is disposed on a crank chamber side wall surface of a forming body that forms a part of the crank chamber side pressure release passage,
The variable capacity compressor according to claim 2, wherein the suppressing unit contacts and separates from the formed body according to a temperature sensed by the temperature sensing unit. The forming body forming a part of the crank chamber side pressure release passage has a protruding portion formed by protruding a peripheral edge portion of the passage opening on the side wall surface of the crank chamber, and the protruding portion has a notch groove at the protruding end portion. The groove cross-sectional area of the notch groove is configured to be opened larger than the flow path cross-sectional area of the throttle means,
The discharge suppression means is
A temperature sensing part disposed on a crank chamber side wall of the formed body, sensing a temperature of the crank chamber, and being displaceable in a release direction of the suppression according to the sensed temperature;
The suppression unit is provided at the displacement end of the temperature sensing unit, and the suppression unit is brought into contact with and separated from the protruding end according to the sensed temperature of the temperature sensing unit,
Only the notch groove can be opened to the crank chamber side, the restraining part is brought into contact with the projecting end part, the restraint is performed via the notch groove, and when the sensed temperature is equal to or higher than the predetermined temperature, The variable displacement compressor according to claim 1, wherein the suppression unit is displaced in a release direction of the suppression to release the suppression. The formed body has a recess in the side wall surface of the crank chamber,
A part of the crank chamber side pressure release passage is configured to open toward the crank chamber side at the bottom of the recess,
The variable displacement compressor according to claim 3 or 4, wherein the discharge suppression means is disposed at a bottom of the recess. A plurality of the cylinder bores are arranged in the circumferential direction in the forming body,
The variable capacity compressor according to claim 5, wherein the concave portion is disposed so as to be surrounded by the cylinder bores. The drive shaft is supported through the bottom of the recess across the center of the crank chamber,
7. The variable capacity compressor according to claim 5, wherein a part of the crank chamber side pressure release passage is opened below a center axis of the drive shaft in a gravitational direction.   The variable displacement compressor according to any one of claims 1 to 7, wherein the discharge suppression means is made of a bimetal or a shape memory alloy. The compression mechanism includes, in the crank chamber, a rotor fixed to the drive shaft, and a swash plate that is connected to the rotor via a connecting unit so that an inclination angle with respect to a central axis of the drive shaft is variable. Because
9. The reciprocating motion of the piston by the rotational movement of the swash plate, changing the tilt angle of the swash plate to change the stroke amount of the piston, and changing the discharge capacity of the refrigerant from the cylinder bore. The variable capacity compressor according to any one of the above.