Variable displacement compressor

Abstract

To reduce inflow of foreign matters into a capacity control valve controlling an emission capacity of a refrigerant in a variable displacement compressor.SOLUTION: A swash plate compressor 100 as one example of a capacity variable compressor has: a suction chamber 150; a compression mechanism for sucking and compressing its refrigerant; an emission chamber 152 for emitting the refrigerant compressed by the compression mechanism; a crank chamber 110 for changing a state of the compression mechanism according to internal pressure; and a capacity control valve 200 arranged on a pressure supply passage 156 through which the emission chamber 152 and the crank chamber 110 communicate with each other. The capacity control valve 200 has plural introduction ports, and controls an emission capacity of the refrigerant by increasing / decreasing a flow rate of the refrigerant supplied from the emission chamber 152 to the crank chamber 110 to change the internal pressure of the crank chamber 110. Then, a cross sectional area of the pressure supply passage 156 opened on the emission chamber 152 is larger than a total cross sectional area of the plural introduction ports of the capacity control valve 200.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a variable capacity compressor capable of varying the discharge capacity of a refrigerant.

Background Art

[0002] In a variable capacity compressor, as described in Japanese Patent Application Laid-Open No. 2017-31834 (Patent Document 1), a capacity control valve for controlling the discharge capacity of the refrigerant is disposed in the middle of a communication passage that communicates a discharge chamber and a crank chamber (control pressure chamber). The capacity control valve controls the discharge capacity of the refrigerant by changing the state of a compression mechanism that compresses the refrigerant by increasing or decreasing the flow rate of the refrigerant supplied from the discharge chamber to the crank chamber and changing the internal pressure of the crank chamber.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, since the cross-sectional area of the communication passage that communicates the discharge chamber and the crank chamber is not optimized, particularly in a situation where the flow velocity of the refrigerant in the discharge chamber is relatively slow, the refrigerant is constricted by the opening of the communication passage and the flow velocity increases, and foreign matter mixed in the refrigerant and the lubricating oil mixed with the refrigerant easily flows into the communication passage.

[0005] Therefore, an object of the present invention is to provide a variable capacity compressor capable of reducing the inflow of foreign matter into a capacity control valve that controls the discharge capacity of a refrigerant.

Means for Solving the Problems

[0006] A variable displacement compressor comprises an intake chamber into which refrigerant is introduced, a compression mechanism that draws in and compresses the refrigerant from the intake chamber, a discharge chamber from which the refrigerant compressed by the compression mechanism is discharged, a control pressure chamber that changes the state of the compression mechanism according to the internal pressure, and a displacement control valve located in a communication passage connecting the discharge chamber and the control pressure chamber. The displacement control valve has multiple inlet ports and controls the refrigerant discharge capacity by increasing or decreasing the flow rate of refrigerant supplied from the discharge chamber to the control pressure chamber, thereby changing the internal pressure of the control pressure chamber. The cross-sectional area of ​​the communication passage opening to the discharge chamber is larger than the total cross-sectional area of ​​the multiple inlet ports of the displacement control valve. [Effects of the Invention]

[0007] According to the present invention, in a variable displacement compressor, the inflow of foreign matter into the displacement control valve that controls the discharge capacity of the refrigerant can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This is a longitudinal cross-sectional view of a swashplate compressor, which is an example of a variable displacement compressor. [Figure 2] This is a perspective view showing an example of the internal structure of a cylinder head. [Figure 3] This is a cross-sectional view of a key part showing an example of the mounting structure of a capacity control valve. [Figure 4] This is a front view showing an example of a cylinder head in which a pressure supply passage has been formed. [Figure 5] This is a cross-sectional view of a key part showing an example of a cylinder head in which a pressure supply passage is formed. [Figure 6] This is a cross-sectional view of a key part showing a modified example of the pressure supply passage. [Figure 7] This is a cross-sectional view of a key part showing a modified example of the pressure supply passage. [Figure 8] This is a front view showing another example of a cylinder head in which a pressure supply passage is formed. [Figure 9] This is a cross-sectional view of BB in Figure 8. [Modes for carrying out the invention]

[0009] The embodiments for carrying out the present invention will be described in detail below with reference to the attached drawings. Figure 1 shows an example of a swashplate compressor 100, which is an example of a variable displacement compressor. The swashplate compressor 100 is incorporated, for example, into the refrigerant circulation circuit of an air conditioning system of a vehicle (not shown), and draws in refrigerant from the low-pressure side of the refrigerant circulation circuit, compresses it, and discharges the compressed refrigerant to the high-pressure side of the refrigerant circulation circuit. Note that the variable displacement compressor is not limited to the swashplate compressor 100 shown, but may be any compressor that is well known to those skilled in the art.

[0010] The swashplate compressor 100 includes a cylinder block 102 in which a plurality of cylinder bores 102A are formed, a front housing 104 joined to one axial end of the cylinder block 102, and a cylinder head 108 joined to the other axial end of the cylinder block 102 via a valve plate 106.

[0011] A crank chamber 110 is formed by the cylinder block 102 and the front housing 104, and a drive shaft 112 is positioned to pass through the inside of this crank chamber 110 in the axial direction. A disc-shaped swash plate 114 is positioned inside the crank chamber 110. A through hole 114A is formed in the center of the swash plate 114, and the drive shaft 112 passes through the through hole 114A of the swash plate 114. The swash plate 114 is also connected to a disc-shaped rotor 116, which is integrally fixed to the drive shaft 112, via a link mechanism 118. Here, the crank chamber 110 constitutes a control pressure chamber that changes the state of the compression mechanism, which is composed of the cylinder bore 102A of the cylinder block 102, the piston 146 (described later), and the swash plate 114, according to the internal pressure.

[0012] The link mechanism 118 includes a first arm 116A protruding from the rotor 116, a second arm 114B protruding from the swash plate 114, and a link arm 120 connecting the tip of the first arm 116A and the tip of the second arm 114B. One end of the link arm 120 is rotatably connected to the first arm 116A via a first connecting pin 122. The other end of the link arm 120 is rotatably connected to the second arm 114B via a second connecting pin 124. Therefore, the swash plate 114 rotates integrally with the drive shaft 112 by the link mechanism 118, and its tilt angle can be changed along the axial direction of the drive shaft 112.

[0013] The through-hole 114A of the swash plate 114 is shaped to allow the swash plate 114 to tilt within a range between the minimum and maximum tilt angles. Specifically, the through-hole 114A has a minimum tilt angle restricting portion that contacts the outer circumferential surface of the drive shaft 112 to restrict the tilt angle displacement (tilting) of the swash plate 114 in the direction of decreasing the tilt angle. The through-hole 114A also has a maximum tilt angle restricting portion that contacts the outer circumferential surface of the drive shaft 112 to restrict the tilt of the swash plate 114 in the direction of increasing the tilt angle. Therefore, the swash plate 114 can tilt freely with respect to the axial direction of the drive shaft 112 between the minimum tilt angle restricted by the minimum tilt angle restricting portion and the maximum tilt angle restricted by the maximum tilt angle restricting portion.

[0014] On the drive shaft 112, between the swash plate 114, are positioned a tilt angle reducing spring 126 that biases the swash plate 114 in a direction that decreases the tilt angle, and a tilt angle increasing spring 128 that biases the swash plate 114 in a direction that increases the tilt angle. Specifically, the tilt angle reducing spring 126 is positioned between the swash plate 114 and the rotor 116, and the tilt angle increasing spring 128 is positioned between the swash plate 114 and a disc-shaped spring support member 130 that is fixed to or formed on the drive shaft 112.

[0015] Here, the biasing force of the inclination angle increasing spring 128 is set to be greater than the biasing force of the inclination angle decreasing spring 126 when the inclination angle of the swash plate 114 is the minimum inclination angle. Therefore, when the drive shaft 112 is not rotating, that is, when the swash plate type compressor 100 is stopped, the swash plate 114 is positioned at an inclination angle (> minimum inclination angle) where the biasing force of the inclination angle decreasing spring 126 and the biasing force of the inclination angle increasing spring 128 are balanced. The inclination angle at which the biasing force of the inclination angle decreasing spring 126 and the biasing force of the inclination angle increasing spring 128 are balanced is set as the minimum inclination angle range where the compression operation by the piston 146 described later is ensured. For example, if the inclination angle when the swash plate 114 is orthogonal to the axial direction of the drive shaft 112 is set as 0 degrees (minimum inclination angle), it can be set in the range of 1 to 3 degrees.

[0016] One end of the drive shaft 112 penetrates through the cylindrical boss portion 104A of the front housing 104 and extends to the outside thereof, and is connected to a pulley 134 that is fitted to be relatively rotatable with respect to the outer peripheral surface of the boss portion 104A via an electromagnetic clutch 132. Further, the drive shaft 112 and the rotor 116 are supported in the radial direction by bearings 136 and 138, and are supported in the thrust direction by bearings 140 and a thrust plate 142. The distance between the other end of the drive shaft 112 and the thrust plate 142 is adjusted by an adjusting screw 144 to have a predetermined gap.

[0017] Then, when the electromagnetic clutch 132 is actuated in a state where the rotational driving force from an electric motor or an engine (not shown) is transmitted to the pulley 134, the pulley 134 and the drive shaft 112 are connected and the drive shaft 112 is rotationally driven. When the electromagnetic clutch 132 is stopped, the pulley 134 and the drive shaft 112 are disengaged, so that the swash plate type compressor 100 can be stopped.

[0018] Further, the swash plate type compressor 100 has the same number of pistons 146 as the plurality of cylinder bores 102A formed in the cylinder block 102. Each piston 146 has a piston body 146A arranged to be axially movable with respect to the cylinder bore 102A, and an extension portion 146B extending axially from the piston body 146A toward the inside of the crank chamber 110.

[0019] An accommodation portion 146C capable of accommodating a pair of shoes 148 arranged sandwiching the vicinity of the peripheral edge of the swash plate 114 is formed in the extension portion 146B of the piston 146. That is, the piston 146 is connected to the swash plate 114 via a pair of shoes 148 arranged sandwiching the vicinity of the peripheral edge of the swash plate 114. Therefore, the piston 146 reciprocates in the cylinder bore 102A of the cylinder block 102 by the rotation of the swash plate 114.

[0020] As shown in FIG. 2, an intake chamber 150 arranged at the center and a discharge chamber 152 arranged to annularly surround the intake chamber 150 are respectively formed in the cylinder head 108. The intake chamber 150 communicates with each cylinder bore 102A of the cylinder block 102 via an intake hole 106A formed in the valve plate 106 and an intake valve (not shown). The discharge chamber 152 communicates with each cylinder bore 102A of the cylinder block 102 via a plurality of discharge holes 106B formed in the valve plate 106 and a discharge valve (not shown).

[0021] Here, the front housing 104, the cylinder block 102, the valve plate 106, the cylinder head 108, etc. are mutually fastened by a plurality of through bolts 154 with a gasket (not shown) arranged between the members as required, and a compressor housing is formed.

[0022] As shown in Figure 1, the cylinder head 108 has an intake passage 108A that connects the low-pressure side of the refrigerant circulation circuit of the air conditioning system to the intake chamber 150, and a discharge passage 108B that connects the high-pressure side of the refrigerant circulation circuit of the air conditioning system to the discharge chamber 152. The cylinder head 108 also has a check valve (not shown) that opens and closes the discharge passage 108B. This check valve operates in response to the pressure difference between the pressure in the discharge chamber 152 upstream and the pressure in the discharge passage 108B downstream. When this pressure difference is less than a predetermined value, it closes the discharge passage 108B, and when this pressure difference is greater than or equal to a predetermined value, it opens the discharge passage 108B.

[0023] A cylindrical capacity control valve 200 is mounted at a predetermined location on the cylinder head 108 to adjust the opening of a pressure supply passage 156 that connects the discharge chamber 152 and the crank chamber 110. By adjusting the opening of the pressure supply passage 156, the capacity control valve 200 increases or decreases the flow rate of high-pressure refrigerant supplied from the discharge chamber 152 to the crank chamber 110, thereby changing the internal pressure of the crank chamber 110 and controlling the refrigerant discharge capacity. Furthermore, the refrigerant present inside the crank chamber 110 flows into the intake chamber 150 via a pressure relief passage 158 formed by a communication passage 102B and space 102C formed in the cylinder block 102, and an orifice 106C formed in the valve plate 106. Therefore, by changing the internal pressure of the crank chamber 110 with the capacity control valve 200, the inclination angle of the swash plate 114, i.e., the stroke of the piston 146, can be changed, thereby variably controlling the discharge capacity of the swash plate compressor 100. Here, the pressure supply passage 156 is given as an example of a connecting passage.

[0024] As shown in Figure 3, the capacity control valve 200 is fitted and fixed into a stepped control valve mounting hole 108C formed on the side of the cylinder head 108 toward the interior. The capacity control valve 200 is an electromagnetic control valve that adjusts the opening degree of the pressure supply passage 156 in response to an input signal from the outside. On the outer circumferential surface of the capacity control valve 200, at two positions spaced apart in the axial direction, there are multiple inlet ports (not shown) for introducing high-pressure refrigerant supplied from the discharge chamber 152 into the interior, and multiple discharge ports (not shown) for discharging high-pressure refrigerant whose flow rate is adjusted according to the change in the opening degree of the pressure supply passage 156. Here, the multiple inlet ports and the multiple discharge ports are arranged, for example, at positions that equally divide the area around the central axis of the capacity control valve 200.

[0025] Furthermore, short, cylindrical filters 210 and 220 are attached to the outer circumferential surface of the capacity control valve 200 at positions covering multiple inlet ports and multiple discharge ports, respectively. Additionally, O-rings 230 are attached to the outer circumferential surface of the capacity control valve 200 at locations between the two filters 210 and 220, and at locations on both axially outward sides of the two filters 210 and 220, respectively, to seal with the inner circumferential surface of the control valve mounting hole 108C of the cylinder head 108. Thus, the three O-rings attached to the outer circumferential surface of the capacity control valve 200 can seal at least the inlet ports and discharge ports in an airtight manner. Note that the cylinder head 108 has annular gaps (spaces) formed around the outer circumferential surfaces of the two filters 210 and 220 attached to the outer circumferential surface of the capacity control valve 200, through which high-pressure refrigerant flows.

[0026] The pressure supply passage 156, located upstream of the capacity control valve 200, extends linearly so as to open at a position facing the outer surface of the filter 210, which is mounted around the inlet port of the capacity control valve 200, when the capacity control valve 200 is fitted and fixed in the control valve mounting hole 108C. Therefore, the high-pressure refrigerant supplied from the discharge chamber 152 via the pressure supply passage 156 directly strikes the outer surface of the filter 210, which is mounted around the inlet port of the capacity control valve 200. The high-pressure refrigerant supplied to the outer surface of the filter 210 then flows through the annular gap formed around the filter 210, passes through the filter material of the filter 210, and flows into the interior of the capacity control valve 200 from the multiple inlet ports. Subsequently, the high-pressure refrigerant discharged from the multiple discharge ports of the capacity control valve 200 flows through the filter 220 mounted around the multiple discharge ports into the gap, flows through that gap, enters the pressure supply passage 156 located downstream of the capacity control valve 200, and is supplied to the crank chamber 110.

[0027] Here, we will explain the operation of the swashplate compressor 100. When the electromagnetic clutch 132 is activated while rotational driving force from an electric motor or engine is transmitted to the pulley 134, the pulley 134 and the drive shaft 112 are connected via the electromagnetic clutch 132, and the drive shaft 112 begins to rotate. When the drive shaft 112 begins to rotate, the swash plate 114, which is connected to the rotor 116 and the linkage mechanism 118, which are integrated with the drive shaft 112, also begins to rotate. When the swash plate compressor 100 is stopped, as described above, the swash plate 114 is in the minimum inclination angle range that ensures compression by the piston 146, so the piston 146 connected to the swash plate 114 reciprocates within the cylinder bore 102A of the cylinder block 102. When piston 146 moves to the left (front) in Figure 1, the volume of the compression chamber, which is partitioned by piston 146 and cylinder bore 102A, increases, creating negative pressure. Low-pressure refrigerant introduced from the low-pressure side of the refrigerant circulation circuit to the intake chamber 150 via the intake passage 108A is then drawn into the compression chamber through the intake hole 106A and intake valve formed in valve plate 106. When piston 146 moves to the right (rear) in Figure 1, the volume of the compression chamber decreases, creating positive pressure. High-pressure refrigerant present in the compression chamber is then discharged into the discharge chamber 152 through the discharge hole 106B and discharge valve formed in valve plate 106.

[0028] Most or all of the high-pressure refrigerant discharged into the discharge chamber 152 is separated into lubricating oil and high-pressure refrigerant by an oil separator (not shown) attached to the cylinder head 108. The high-pressure refrigerant is then discharged to the high-pressure side of the refrigerant circulation circuit via the discharge passage 108B, while the lubricating oil is returned to the lower part of the crankcase 110 via a lubricating oil passage (not shown). In addition, a portion of the high-pressure refrigerant discharged into the discharge chamber 152 is supplied to the capacity control valve 200 via a pressure supply passage 156 connecting the discharge chamber 152 and the crankcase 110. The high-pressure refrigerant supplied to the capacity control valve 200 flows through an annular gap formed around the filter 210, passing through the filter 210 to capture foreign matter, and then flows into the interior of the capacity control valve 200 through multiple inlet ports.

[0029] The capacity control valve 200 responds to an external operating signal by increasing or decreasing the opening of its internal passages, thereby adjusting the flow rate of high-pressure refrigerant flowing in from multiple inlet ports and discharging high-pressure refrigerant from multiple discharge ports. At this time, the capacity control valve 200 senses the internal pressure of the intake chamber 150 and changes the lift amount of the valve body to automatically adjust the internal pressure of the crank chamber 110 so that the internal pressure of the intake chamber 150 remains constant. The high-pressure refrigerant discharged from the multiple discharge ports is then filtered by filters 220 mounted around the multiple discharge ports to capture foreign matter, then flows through an annular gap formed around the filters 220, flows into a pressure supply passage 156 located downstream of the capacity control valve 200, and is supplied to the crank chamber 110.

[0030] When the supply of high-pressure refrigerant to the crank chamber 110 is cut off, the internal pressure of the crank chamber 110 decreases, increasing the inclination angle of the swash plate 114. As the inclination angle of the swash plate 114 increases, the stroke of the piston 146, which is connected to the swash plate 114 via the link mechanism 118, increases, and the discharge capacity from the compression chamber also increases. As a result, the flow rate of high-pressure refrigerant discharged from the compression chamber to the discharge chamber 152 increases, and consequently, the flow rate of high-pressure refrigerant discharged from the swash plate compressor 100 to the high-pressure side of the refrigerant circulation circuit also increases.

[0031] By the way, if the cross-sectional area of ​​the pressure supply passage 156 located upstream of the capacity control valve 200 is not optimized considering the flow velocity of the high-pressure refrigerant supplied from the discharge chamber 152 to the capacity control valve 200, the following problems may occur, especially when the flow velocity of the high-pressure refrigerant in the discharge chamber 152 is relatively slow. That is, when the flow velocity of the high-pressure refrigerant in the discharge chamber 152 is relatively slow, and considering the flow of high-pressure refrigerant from the discharge chamber 152 to the pressure supply passage 156, the inlet to the pressure supply passage 156 functions as a throttling, so the flow velocity of the high-pressure refrigerant flowing from the discharge chamber 152 to the pressure supply passage 156 increases. When the flow velocity of the high-pressure refrigerant flowing into the pressure supply passage 156 increases, for example, the high-pressure refrigerant before the lubricating oil is separated by the oil separator becomes more likely to flow into the pressure supply passage 156, and as a result, foreign matter mixed in the lubricating oil contained in the high-pressure refrigerant also becomes more likely to flow into the pressure supply passage 156. Most of the foreign matter that flows into the pressure supply passage 156 can be captured by the filter 210 of the capacity control valve 200. However, because the size of the foreign matter is smaller than the opening of the filter 210, it may flow into the inside of the capacity control valve 200, obstructing the operation of the valve body and making it impossible to control the refrigerant discharge capacity.

[0032] Therefore, in this embodiment, as shown in Figures 4 and 5, the cross-sectional area of ​​the pressure supply passage 156 opening into the discharge chamber 152 is formed to be larger than the total cross-sectional area of ​​the multiple inlet ports of the capacity control valve 200. That is, the total cross-sectional area of ​​the multiple inlet ports of the capacity control valve 200 is determined, and the cross-sectional area of ​​the pressure supply passage 156 opening into the discharge chamber 152, in other words, the cross-sectional area of ​​the pressure supply passage 156 located upstream of the capacity control valve 200, is determined to be larger than this total cross-sectional area. Then, using a drill that matches the determined cross-sectional area, the pressure supply passage 156 is formed so that the portion located upstream of the capacity control valve 200 has a uniform cross-sectional area over its entire length.

[0033] In this way, the cross-sectional area of ​​the pressure supply passage 156 located upstream of the capacity control valve 200 becomes larger than the total cross-sectional area of ​​the multiple inlet ports. As a result, the throttling function at the inlet to the pressure supply passage 156 is weakened, and the flow velocity of the high-pressure refrigerant flowing from the discharge chamber 152 into the pressure supply passage 156 decreases. When the flow velocity of the high-pressure refrigerant flowing into the pressure supply passage 156 decreases, for example, it becomes more difficult for the high-pressure refrigerant before the lubricating oil is separated by the oil separator to flow into the pressure supply passage 156. Consequently, foreign matter mixed in the lubricating oil contained in the high-pressure refrigerant also becomes less likely to flow into the pressure supply passage 156. Furthermore, as the amount of foreign matter flowing into the pressure supply passage 156 decreases, the amount of foreign matter flowing into the inside of the capacity control valve 200 also decreases, making it less likely for the movement of the valve body of the capacity control valve 200 to be obstructed by foreign matter, thereby suppressing the inability to control the refrigerant discharge capacity.

[0034] <<First variation>> If the cross-sectional area of ​​the pressure supply passage 156 located upstream of the capacity control valve 200 is made uniform along its entire length, the pressure supply passage 156 may interfere with the O-rings 230 located on both sides in the axial direction of the filter 210 of the capacity control valve 200. In this case, as shown in Figures 6 and 7, the cross-sectional area of ​​the pressure supply passage 156 is made smaller as it approaches the capacity control valve 200 from the discharge chamber 152. Specifically, in the first modified example shown in Figure 6, the cross-sectional area of ​​the pressure supply passage 156 is made smaller near the capacity control valve 200. Also, in the first modified example shown in Figure 7, the cross-sectional area of ​​the pressure supply passage 156 is made smaller in the intermediate section as it approaches the capacity control valve 200 from the discharge chamber 152.

[0035] In this way, interference between the pressure supply passage 156 and the O-ring 230 can be avoided, and for example, the range in which the pressure supply passage 156 can be formed can be expanded, and the direction in which the pressure supply passage 156 extends can be optimized. Although the flow velocity of the high-pressure refrigerant increases as the cross-sectional area of ​​the pressure supply passage 156 decreases on the way from the discharge chamber 152 to the capacity control valve 200, this does not have a significant impact because the absolute amount of foreign matter flowing into the pressure supply passage 156 is reduced.

[0036] <<Second variation>> Depending on the layout of the cylinder head 108 of the variable displacement compressor 100, it may be difficult to change the cross-sectional area of ​​the pressure supply passage 156 located upstream of the displacement control valve 200. In this case, as shown in Figures 8 and 9, multiple pressure supply passages 156 (two in the illustrated example) are formed upstream of the displacement control valve 200, so that the total cross-sectional area of ​​the pressure supply passages 156 opening into the discharge chamber 152 is greater than the total cross-sectional area of ​​the multiple inlet ports of the displacement control valve 200. In the illustrated example, taking into account the layout of the cylinder head 108, pressure supply passages 156 are formed from two positions in the discharge chamber 152 formed in the cylinder head 108, separated by a predetermined distance, and extending diagonally to the displacement control valve 200.

[0037] In this way, even if the cross-sectional area of ​​the pressure supply passage 156 cannot be changed by the layout of the cylinder head 108, by forming multiple pressure supply passages 156 located upstream of the capacity control valve 200, the total cross-sectional area of ​​the multiple pressure supply passages 156 opening into the discharge chamber 152 becomes larger than the total cross-sectional area of ​​the multiple inlet ports of the capacity control valve 200. Therefore, even with cylinder heads 108 having various layouts, the total cross-sectional area of ​​the multiple pressure supply passages 156 opening into the discharge chamber 152 can be made larger than the total cross-sectional area of ​​the multiple inlet ports of the capacity control valve 200.

[0038] Furthermore, those skilled in the art will readily understand that new embodiments can be created by omitting some of the technical ideas of the various embodiments described above, combining some of them as appropriate, or substituting some of them with well-known technologies.

[0039] For example, the link mechanism 118 connecting the rotor 116 and the swash plate 114 is not limited to the configuration described above, but may be a well-known link mechanism. Furthermore, the swash plate compressor 100 does not necessarily have a pulley 134 to which the rotational driving force of an electric motor or engine is transmitted, and an electromagnetic clutch 132 to which the pulley 134 and the drive shaft 112 are connected. [Explanation of Symbols]

[0040] 100 Swashplate compressor (variable displacement compressor) 102A Cylinder bore (compression mechanism) 110 Crank chamber (control pressure chamber) 114 Swash plate (compression mechanism) 146 Piston (compression mechanism) 150 Suction chamber 152 Discharge chamber 156 Pressure supply passage (connecting passage) 200 Capacity Control Valve

Claims

1. The intake chamber into which the refrigerant is introduced, A compression mechanism that draws in and compresses the refrigerant from the aforementioned intake chamber, A discharge chamber through which the refrigerant compressed by the compression mechanism is discharged, A control pressure chamber that changes the state of the compression mechanism according to the internal pressure, A capacity control valve, having multiple inlet ports, is positioned in a communication passage connecting the discharge chamber and the control pressure chamber, and controls the refrigerant discharge capacity by increasing or decreasing the flow rate of refrigerant supplied from the discharge chamber to the control pressure chamber, thereby changing the internal pressure of the control pressure chamber. It has, A variable displacement compressor in which the cross-sectional area of ​​the communication passage opening into the discharge chamber is greater than the total cross-sectional area of ​​the multiple inlet ports of the displacement control valve.

2. The cross-sectional area of ​​the aforementioned communication passage decreases as it moves from the discharge chamber to the capacity control valve. A variable displacement compressor according to claim 1.

3. By forming multiple communication passages located upstream of the capacity control valve, the total cross-sectional area of ​​the multiple communication passages opening into the discharge chamber is larger than the total cross-sectional area of ​​the multiple inlet ports of the capacity control valve. A variable displacement compressor according to claim 1.

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