Volume control valve

Abstract

The present application provides a capacity control valve with high control accuracy and excellent energy efficiency in normal control. The capacity control valve (V) has a valve housing (10) formed with a discharge port (12) through which a discharge fluid of a discharge pressure (Pd) passes, a suction port (13) through which a suction fluid of a suction pressure (Ps) passes, and a control port (13) through which a control fluid of a control pressure (Pc) passes; a rod (83) driven by a solenoid (80); and a main valve (50) composed of a main valve seat (10a) and a main valve core (51), the communication between the discharge port (12) and the control port (14) being opened and closed by the movement of the rod (83), the capacity control valve being provided with a CS valve (56) between the control port (13) and the suction port (14), the CS valve (56) being controlled by the dynamic pressure of the fluid flowing from the discharge port (12) to the control port (13) through the opening of the main valve (50).

Description

[0001] This application is a divisional application of Chinese application filed on April 2, 2020, with application number 202080026878.6 and invention title "Capacity Control Valve". Technical Field

[0002] This invention relates to a capacity control valve for variable control of the volume of a working fluid, for example, to a capacity control valve for controlling the discharge volume of a variable capacity compressor used in an automotive air conditioning system based on pressure. Background Technology

[0003] Variable capacity compressors used in air conditioning systems of automobiles and other vehicles include: a rotating shaft driven by an engine, a swashplate connected to the rotating shaft at a variable tilt angle, and a compression piston connected to the swashplate. By changing the tilt angle of the swashplate, the stroke of the piston is varied, thereby controlling the fluid discharge rate. A capacity control valve, driven by electromagnetic force, is used to control the pressure within the control chamber (Ps for suction of fluid), the discharge pressure (Pd for discharge of fluid pressurized by the piston) and the control pressure (Pc for the control chamber housing the swashplate). This allows for continuous variation of the swashplate's tilt angle.

[0004] During continuous operation of the variable capacity compressor (hereinafter, sometimes simply referred to as "continuous operation"), the capacity control valve is normally controlled as follows: energized by the control computer, the main valve core is moved axially by the electromagnetic force generated by the solenoid, opening and closing the main valve to adjust the control pressure Pc in the control chamber.

[0005] During normal operation of the capacity control valve, the pressure in the control chamber of the variable capacity compressor is appropriately controlled, and the tilt angle of the swashplate relative to the rotating shaft is continuously changed, thereby changing the piston stroke to control the amount of fluid discharged from the discharge chamber and adjusting the air conditioning system to the desired cooling capacity.

[0006] In such a variable capacity compressor, if the compressor remains stationary for an extended period after stopping, the suction pressure Ps, discharge pressure Pd, and control pressure Pc become equalized. The control pressure Pc and suction pressure Ps are significantly higher than during continuous operation, potentially causing liquefaction in a portion of the fluid within the control chamber. When starting the compressor from this state, the control pressure Pc is much higher than during continuous operation, and the control chamber struggles to reach its maximum capacity due to the liquefied fluid, requiring a considerable amount of time to control the discharge to the target value. Therefore, a capacity control valve exists that, upon compressor startup, discharges the liquefied fluid from the compressor's control chamber within a short time.

[0007] The capacity control valve shown in Patent Document 1 includes: a valve body having a discharge port (i.e., a first connecting passage) connecting a first valve chamber having a main valve seat (i.e., a first valve seat) to a discharge chamber of a variable capacity compressor; a suction port (i.e., a second connecting passage) connecting a second valve chamber having a second valve seat to a suction chamber of a variable capacity compressor; and a control port (i.e., a third connecting passage) connecting a pressure-sensitive chamber (i.e., a third valve chamber) formed on the axially opposite side of the second valve chamber with reference to the first valve chamber to a control chamber of the variable capacity compressor; and a main valve core integrally having a first valve core that contacts or separates from the first valve seat within the first valve chamber to open or close the connection between the discharge chamber and the control chamber. A valve section, and a second valve section that contacts or separates from a second valve seat within a second valve chamber to open and close the connection between the control chamber and the suction chamber, and which performs reciprocating opening and closing actions in opposite directions; an intermediate connecting passage that connects the second valve chamber to a third valve chamber; a pressure-sensitive element disposed within the third valve chamber that applies a force to the main valve core in the opening direction of the main valve according to the surrounding fluid pressure; a connector having an annular sealing surface, the free end of which contacts or separates from a pressure-sensitive valve seat integrally disposed on the main valve core in the extension direction of the pressure-sensitive element to open and close the connection between the third valve chamber and the intermediate connecting passage; and a solenoid that applies a driving force to the main valve core.

[0008] When the variable capacity compressor starts, energizing the solenoid of the capacity control valve causes the main valve core to move axially. Simultaneously, the first valve section closes the main valve, and the second valve section opens the second valve. Furthermore, the pressure-sensitive element contracts due to the control pressure Pc and suction pressure Ps being much higher than during continuous operation, and the pressure-sensitive valve opens, thereby forming a flow path within the valve housing connecting the third valve chamber to the second valve chamber via an intermediate connecting passage. Additionally, as the variable capacity compressor starts, the suction pressure Ps in the suction chamber decreases, causing the liquefied fluid in the control chamber, which is under high pressure, to move due to the pressure difference with the suction chamber and be discharged within a short time through the flow path formed in the valve housing. Furthermore, an auxiliary connecting passage connecting the intermediate connecting passage to the third valve chamber is provided in the main valve core, thereby facilitating the discharge of fluid from the control chamber to the suction chamber during the start-up of the variable capacity compressor.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent No. 5167121 (paragraph 0052) Figure 4 ) Summary of the Invention

[0012] The problem that the invention aims to solve

[0013] However, in Patent Document 1, an auxiliary connecting path is provided, so that the suction port, i.e., the second connecting path, and the control port, i.e., the third connecting path, are always connected. When the capacity control valve is under normal control, when the main valve is opened, part of the fluid flowing through the main valve to the third valve chamber is discharged to the suction chamber through the auxiliary connecting path, the intermediate connecting path, and the second connecting path. Therefore, there are problems with the controllability and energy efficiency of the control pressure Pc.

[0014] This invention was made in response to such a problem, and its purpose is to provide a capacity control valve with high control accuracy and excellent energy efficiency during normal control.

[0015] Methods for solving problems

[0016] To solve the above-mentioned problems, the capacity control valve of the present invention comprises:

[0017] The valve body has an outlet for discharge fluid at discharge pressure, an inlet for suction fluid at suction pressure, and a control port for control fluid at control pressure.

[0018] A rod, driven by a solenoid; and

[0019] The main valve, consisting of a main valve seat and a main valve core, opens and closes the connection between the discharge port and the control port by moving the rod.

[0020] A CS valve is provided between the control port and the suction port, which is controlled by the dynamic pressure of the fluid flowing from the discharge port to the control port through the opening of the main valve.

[0021] Therefore, during normal operation after the variable capacity compressor starts, when the main valve is opened, the CS valve is controlled by the dynamic pressure of the discharge fluid flowing through the main valve to the control port, and the control fluid under control pressure is not discharged from the suction port. Thus, the control accuracy is high and the energy efficiency is excellent during normal control.

[0022] Alternatively, the control port may always be in a state where it can communicate with the main valve.

[0023] Therefore, when the main valve is open and not energized, the discharge port and the control port are connected, thus enabling reliable connection between the discharge chamber and the control chamber.

[0024] Alternatively, the CS valve may have a cylindrical CS valve core and a spring that applies force to the CS valve core in the opening direction.

[0025] Therefore, a capacity control valve with a CS valve can be compactly constructed. Furthermore, when the main valve is closed, the control pressure and suction pressure can be maintained at the same level, thus maintaining maximum capacity and improving operating efficiency.

[0026] Alternatively, the CS valve core may have a bearing surface extending radially.

[0027] As a result, the bearing surface intersects with the flow direction of the discharged fluid, which makes it easy for the discharged fluid flowing to the control port to generate dynamic pressure when the main valve is opened.

[0028] Alternatively, the CS valve core may have an end face that contacts or separates from the CS valve seat, and when force is applied to the CS valve in the opening direction, the end face on the opposite side of the axial direction of the end face abuts against the inner surface of the valve housing.

[0029] Therefore, the maximum opening area of ​​the CS valve can be set by the contact between the CS valve core and the inner surface of the valve body, thus simplifying the structure of the CS valve.

[0030] Alternatively, the CS valve can also function as a differential pressure valve for both the intake pressure and the control pressure.

[0031] Therefore, when the main valve is opened, in addition to the dynamic pressure generated by the flow of the discharged fluid, there is also a differential pressure, so the CS valve can operate reliably.

[0032] Alternatively, it may include a pressure-driven valve that opens and closes based on the suction pressure.

[0033] An intermediate connection path is formed on the main valve core, which enables the control port to connect with the suction port by opening and closing the valve driven by the pressure.

[0034] Therefore, when the suction pressure is high, the pressure-driven valve opens, and the control port connects to the suction port via the intermediate connecting passage, thus enabling the liquid refrigerant in the control chamber to be rapidly discharged into the suction chamber during startup. As a result, the variable capacity compressor exhibits excellent start-up responsiveness.

[0035] Alternatively, the valve housing may be provided with an intake port that is different from the intake port that forms the flow path that is opened and closed by the pressure-driven valve.

[0036] Therefore, by separately providing an intake port that constitutes the flow path opened and closed by the pressure-driven valve and an intake port that constitutes the flow path opened and closed by the CS valve, the structure of the valve housing can be simplified. Attached Figure Description

[0037] Figure 1 This is a schematic diagram showing the structure of a swashplate variable capacity compressor assembled with the capacity control valve of Embodiment 1 of the present invention;

[0038] Figure 2 This is a cross-sectional view showing the main valve closed and the CS valve open when the capacity control valve of Embodiment 1 is energized (under normal control).

[0039] Figure 3This illustrates the situation where, in the energized state of the capacity control valve of Embodiment 1 (under normal control), the main valve is closed and the CS valve is open. Figure 2 Enlarged sectional view;

[0040] Figure 4 This is an enlarged cross-sectional view showing the main valve open and the CS valve closed in the non-energized state of the capacity control valve in Embodiment 1.

[0041] Figure 5 This is an enlarged cross-sectional view showing the situation where the main valve is closed and the CS valve is open in the energized state (normal control) of the capacity control valve in Embodiment 2 of the present invention. Detailed Implementation

[0042] Hereinafter, specific embodiments of the capacity control valve of the present invention will be described with reference to examples.

[0043] Example 1

[0044] Reference Figures 1 to 4 The capacity control valve of Example 1 will be described below. Figure 2 The left and right sides when viewed from the front are described as the left and right sides of the capacity control valve.

[0045] The capacity control valve V of the present invention is assembled in a variable capacity compressor M used in an air conditioning system of automobiles, etc., and performs variable control on the pressure of the refrigerant, i.e., the working fluid (hereinafter referred to as "fluid"), thereby controlling the discharge of the variable capacity compressor M and adjusting the air conditioning system to the desired cooling capacity.

[0046] First, let's explain the variable capacity compressor M. For example... Figure 1 As shown, the variable capacity compressor M has a housing 1, which includes a discharge chamber 2, a suction chamber 3, a control chamber 4, and multiple cylinders 4a. Furthermore, the variable capacity compressor M has a connection path (not shown) that directly connects the control chamber 4 and the suction chamber 3, and this connection path includes a fixed throttling orifice for balancing the pressure between the suction chamber 3 and the control chamber 4.

[0047] Additionally, the variable capacity compressor M includes: a rotating shaft 5, driven by an engine (not shown) located outside the housing 1; a swashplate 6, eccentrically connected to the rotating shaft 5 via a hinge mechanism 8 within the control chamber 4; and multiple pistons 7, connected to the swashplate 6 and freely reciprocating within each cylinder 4a. A capacity control valve V, opened and closed by electromagnetic force, utilizes the suction pressure Ps of the suction chamber 3 for fluid intake, the discharge pressure Pd of the discharge chamber 2 for fluid expulsion pressurized by the pistons 7, and the control pressure Pc of the control chamber 4 housing the swashplate 6. The pressure within the control chamber 4 is appropriately controlled to continuously change the tilt angle of the swashplate 6, thereby varying the stroke of the pistons 7 to control the fluid discharge rate. Furthermore, for ease of explanation, in Figure 1 The diagram of the capacity control valve V assembled in the variable capacity compressor M is omitted.

[0048] Specifically, the higher the control pressure Pc in the control chamber 4, the smaller the tilt angle of the swashplate 6 relative to the rotation axis 5, and the less the stroke of the piston 7. However, when the pressure reaches a certain level, the swashplate 6 becomes approximately perpendicular to the rotation axis 5, that is, slightly tilted compared to being perpendicular. At this point, the stroke of the piston 7 is at its minimum, and the pressure exerted by the piston 7 on the fluid in the cylinder 4a is at its minimum. Consequently, the amount of fluid discharged to the discharge chamber 2 decreases, and the cooling capacity of the air conditioning system becomes minimal. On the other hand, the lower the control pressure Pc in the control chamber 4, the larger the tilt angle of the swashplate 6 relative to the rotation axis 5, and the more the stroke of the piston 7. However, when the pressure reaches a certain level, the swashplate 6 reaches its maximum tilt angle relative to the rotation axis 5. At this point, the stroke of the piston 7 is at its maximum, and the pressure exerted by the piston 7 on the fluid in the cylinder 4a is at its maximum. Consequently, the amount of fluid discharged to the discharge chamber 2 increases, and the cooling capacity of the air conditioning system becomes maximum.

[0049] like Figure 2As shown, the capacity control valve V assembled in the variable capacity compressor M adjusts the current energizing the coil 86 constituting the solenoid 80 to control the opening and closing of the main valve 50 in the capacity control valve V. Furthermore, the suction pressure Ps in the intermediate connecting passage 55 actuates the pressure-sensitive element 61 to control the opening and closing of the pressure-sensitive valve 54, which acts as a pressure-driven valve. This controls the fluid flowing into or out of the control chamber 4, thereby providing variable control of the control pressure Pc within the control chamber 4. Additionally, the intermediate connecting passage 55 extends axially through a hollow hole formed inside the main and auxiliary valve cores 51 (which serve as the main valve core) and the pressure-sensitive valve component 52, forming a flow path for discharging liquid refrigerant. In detail, if the variable capacity compressor M is left in a stopped state for a long time, the fluid under high pressure in the control chamber 4 may liquefy. By starting the variable capacity compressor M and energizing the capacity control valve V, the main valve 50 is closed and the auxiliary valve 53 is opened. As a result, the pressure-sensitive element 61 contracts due to the high suction pressure Ps in the intermediate connecting passage 55, and the pressure-sensitive valve 54 opens. This allows the liquid refrigerant in the control chamber 4 to be discharged to the suction chamber 3 through the intermediate connecting passage 55 in a short time.

[0050] In this embodiment, the main valve 50 is composed of a main and auxiliary valve core 51 and a main valve seat 10a formed on the inner circumferential surface of the valve housing 10. The main valve 50 is opened and closed by contacting or separating the main valve seat 10a with the axial left end 51a of the main and auxiliary valve core 51. The auxiliary valve 53 is composed of a main and auxiliary valve core 51 and an auxiliary valve seat 82a formed on the inner diameter side of the open end face (i.e., the axial left end face) of the central column 82. The auxiliary valve 53 is opened and closed by contacting or separating the auxiliary valve seat 82a with the axial right end 51b of the main and auxiliary valve core 51. The pressure-sensitive valve 54 is composed of a cover 70 constituting the pressure-sensitive body 61 and a pressure-sensitive valve seat 52a formed on the axial left end of the pressure-sensitive valve component 52. The pressure-sensitive valve 54 is opened and closed by contacting or separating the pressure-sensitive valve seat 52a with the sealing surface 70a formed on the outer diameter side of the axial right end of the cover 70.

[0051] Next, the structure of the capacity control valve V will be explained. For example... Figure 2 As shown, the capacity control valve V mainly consists of the following parts: a valve body 10, which is formed of metal or resin material; main and auxiliary valve cores 51, pressure-sensitive valve component 52, and CS valve core 57, which are arbitrarily reciprocating within the valve body 10; a pressure-sensitive element 61, which applies an axial force to the main and auxiliary valve cores 51 and pressure-sensitive valve component 52 according to the suction pressure Ps in the intermediate connecting passage 55; and a solenoid 80, which is connected to the valve body 10 and applies a driving force to the main and auxiliary valve cores 51 and pressure-sensitive valve component 52. In addition, the capacity control valve V includes a CS valve core 57, which can utilize the dynamic pressure of the fluid flowing through the main valve 50 when the main valve 50 is open to actuate the CS valve 56 (see reference). Figure 3 and Figure 4 )closure.

[0052] In this embodiment, the CS valve 56 consists of a CS valve core 57 and a CS valve seat 11a formed on the axial right end face of the partition adjustment member 11 mounted on the valve housing 10 (see reference). Figure 3 and Figure 4 The CS valve 56 is configured such that it is opened and closed by contacting or separating the end face 57a formed on the axial left end of the CS valve core 57 from the CS valve seat 11a.

[0053] like Figure 2 As shown, the solenoid 80 mainly consists of the following parts: a housing 81 having an opening 81a that opens axially to the left; a generally cylindrical central post 82 that is inserted into the opening 81a of the housing 81 from the axial left and fixed to the inner diameter side of the housing 81; a drive rod 83 that is inserted into the central post 82 and can move freely axially, with its axial left end inserted and fixed to the main and auxiliary valve cores 51; a movable iron core 84 for the axial right end of the drive rod 83 to be inserted and fixed; a helical spring 85 disposed between the central post 82 and the movable iron core 84, which applies force to the movable iron core 84 in the opening direction of the main valve 50, i.e., axial to the right; and an excitation coil 86 that is wound around the outside of the central post 82 via a winding frame.

[0054] A recess 81b is formed on the outer casing 81, with the inner diameter recessed to the right on the left side of the axial direction. The right end of the valve housing 10 is inserted and fixed in the recess 81b in a generally sealed manner.

[0055] The central column 82 is formed of a rigid body made of magnetic materials such as iron and silicon steel, and includes: a cylindrical portion 82b, which has an insertion hole 82c extending axially and through which the drive rod 83 is inserted; and an annular flange portion 82d, which extends from the outer peripheral surface of the axial left end of the cylindrical portion 82b in the outward diameter direction, wherein a secondary valve seat 82a is formed on the inner diameter side of the opening end face of the central column 82, that is, on the axial left end face of the cylindrical portion 82b.

[0056] Furthermore, with the right end face of the flange portion 82d abutting against the bottom surface of the recess 81b of the housing 81 from the left side, the center post 82 is inserted and fixed in the recess 10b in a generally sealed manner. The recess 10b is a recess that is recessed to the left side of the inner diameter of the valve housing 10 at the right end of the valve housing 10, which is inserted and fixed in the recess 81b of the housing 81.

[0057] like Figure 2As shown, the valve housing 10 has the following: a Pd port 12 as a discharge port, which communicates with the discharge chamber 2 of the variable capacity compressor M; a Pc port 13 as a control port, which communicates with the control chamber 4 of the variable capacity compressor M; a first Ps port 14 as a suction port, which communicates with the suction chamber 3 of the variable capacity compressor M; and a second Ps port 15, which is adjacent to the axial right side of the Pd port 12 and communicates with the suction chamber 3 of the variable capacity compressor M.

[0058] The valve housing 10 is generally cylindrical with a bottom by pressing the separation adjustment member 11 into it in a generally sealed manner at its axial left end. In addition, by adjusting the axial position of the separation adjustment member 11, the force of the pressure-sensitive body 61 and the force of the helical spring 58 of the CS valve 56 (described later) can be adjusted.

[0059] The valve housing 10 contains: a first valve chamber 20, which is connected to the Pd port 12 and is disposed on the axial left end 51a side of the main and auxiliary valve cores 51; a second valve chamber 30, which is connected to the second Ps port 15 and is disposed on the back pressure side of the main and auxiliary valve cores 51, i.e., the axial right end 51b side; and a pressure-sensitive chamber 60, which is connected to the Pc port 13 and the first Ps port 14 and is disposed on the CS valve core 57 and the pressure-sensitive body 61.

[0060] Furthermore, inside the valve housing 10, a main and auxiliary valve core 51 and a pressure-sensitive valve component 52, which are flexibly arranged to reciprocate axially, are disposed. A small-diameter guide hole 10c is formed on the inner circumferential surface of the valve housing 10 at its right axial end, allowing the outer circumferential surfaces of the main and auxiliary valve cores 51 to slide in a substantially sealed state. Furthermore, inside the valve housing 10, the first valve chamber 20 and the second valve chamber 30 are separated by the outer circumferential surfaces of the main and auxiliary valve cores 51 and the inner circumferential surface of the guide hole 10c. Additionally, a small gap is formed between the inner circumferential surface of the guide hole 10c and the outer circumferential surface of the main and auxiliary valve cores 51, which are slightly separated radially, allowing the main and auxiliary valve cores 51 to move smoothly relative to the valve housing 10 axially.

[0061] In addition, inside the valve housing 10, a CS valve core 57 is flexibly disposed in the pressure-sensitive chamber 60 along the axial direction. On the inner circumferential surface of the valve housing 10, a small-diameter guide hole 10d is formed at the left end of the axial direction, which allows the outer circumferential surface of the CS valve core 57 to slide in a substantially sealed state.

[0062] like Figure 2 As shown, the main and auxiliary valve cores 51 are configured in a generally cylindrical shape, and an independent pressure-sensitive valve component 52, which is configured in a stepped cylindrical shape and appears to be roughly turret-shaped when viewed from the side, is inserted and fixed in a generally sealed manner at its axial left end. A drive rod 83 is inserted and fixed in a generally sealed manner at its axial right end, and they can move together axially.

[0063] In addition, the labyrinth effect of the annular groove 51c formed on the outer peripheral surface of the main and auxiliary valve cores 51 as a sealing part can suppress the leakage of fluid from the first valve chamber 20 to the second valve chamber 30, thus maintaining the discharge pressure Pd of the discharge fluid supplied from the discharge chamber 2 to the first valve chamber 20 via the Pd port 12.

[0064] like Figure 3 and Figure 4 As shown, the pressure-sensitive valve component 52 is configured in a stepped, generally cylindrical shape as follows: a large-diameter portion 52b, which has a pressure-sensitive valve seat 52a; a medium-diameter portion 52c, which is formed on the axial right side of the large-diameter portion 52b with a diameter smaller than that of the large-diameter portion 52b; and a small-diameter portion 52d, which is formed on the axial right side of the medium-diameter portion 52c with a diameter smaller than that of the medium-diameter portion 52c, and a main and auxiliary valve core 51, which is configured in a generally sealed manner and is generally cylindrical in shape.

[0065] like Figure 2 As shown, the pressure-sensitive body 61 is mainly composed of a bellows core 62 with a built-in helical spring 63 and a circular plate-shaped cover 70 disposed at the axial right end of the bellows core 62. The axial left end of the bellows core 62 is fixed to the separation adjustment component 11.

[0066] Furthermore, the pressure-sensitive element 61 is disposed within the pressure-sensitive chamber 60. A force generated by the helical spring 63 and the bellows core 62 causes the cover 70 to move axially to the right, causing the sealing surface 70a of the cover 70 to sit on the pressure-sensitive valve seat 52a of the pressure-sensitive valve component 52. Additionally, a force is applied to the cover 70 based on the suction pressure Ps in the intermediate connecting passage 55, causing it to move axially to the left.

[0067] like Figure 3 and Figure 4 As shown, the CS valve core 57 is configured in a generally cylindrical shape and is concentrically arranged on the outer diameter side of the pressure-sensitive body 61 within the pressure-sensitive chamber 60. Furthermore, a helical spring 58 is embedded in the mounting portion 57c formed at the axial left end of the CS valve core 57. The axial left end of the helical spring 58 abuts against the axial right end face of the separation adjustment member 11, and the axial right end of the helical spring 58 abuts against the side surface 57g extending radially along the axial right end of the mounting portion 57c.

[0068] In detail, the CS valve core 57 has: a generally cylindrical base 57b; a mounting portion 57c with an annular cutout shape formed at the axial left end of the base 57b; a through hole 57d formed at the axial right end of the base 57b and extending radially; and an annular protrusion 57e protruding from the inner circumference of the base 57b in the inner diameter direction at the axial right side of the through hole 57d. The CS valve core 57 is subjected to a force in the opening direction of the CS valve 56, i.e., axially to the right, by a helical spring 58 embedded in the mounting portion 57c. Furthermore, the through hole 57d is configured to have approximately the same opening area as the Pc port 13 formed in the valve housing 10 and corresponds axially in position.

[0069] Furthermore, on the CS valve core 57, an end face 57a is formed at the axial left end of the mounting portion 57c, which can contact or separate from the CS valve seat 11a formed on the axial right end face of the separating adjustment member 11. Moreover, on the axially opposite side of the end face 57a, i.e., at the axial right end of the base portion 57b, an end face 57f is formed that can abut against the inner surface of the pressure-sensitive chamber 60 in the valve housing 10 when the CS valve 56 is open.

[0070] Furthermore, the annular protrusion 57e of the CS valve core 57 is formed at the position between the Pd port 12 and the Pc port 13 in the valve housing 10, and forms a bearing surface 57h extending radially from the axial right end face. In addition, the inner diameter of the annular protrusion 57e is formed to be smaller than the outer diameter of the large diameter portion 52b of the pressure-sensitive valve component 52, and larger than the outer diameter of the intermediate diameter portion 52c.

[0071] In addition, the capacity control valve V is a structure in which the pressure-sensitive body 61, CS valve core 57 and helical spring 58 are inserted into the pressure-sensitive chamber 60 from the axial left end of the valve body 10, and the separation adjustment component 11 is pressed in and fixed, so the assembly is simple.

[0072] Next, the operation of the capacity control valve V, mainly the opening and closing operations of the main valve 50 and the CS valve 56, will be explained.

[0073] First, the energization state of the capacity control valve V will be explained. For example... Figure 2 and Figure 3 As shown, when the capacity control valve V is energized (i.e., during normal control, or so-called duty cycle control), the electromagnetic force generated by applying current to the solenoid 80 pulls the movable iron core 84 closer to the side of the central column 82, i.e., the left side of the axis. The drive rod 83 fixed to the movable iron core 84, the main and auxiliary valve cores 51, and the pressure-sensitive valve component 52 move together to the left side of the axis. The pressure-sensitive body 61 is pressed to the left side of the axis and retracts, thereby separating the right end 51b of the main and auxiliary valve cores 51 from the auxiliary valve seat 82a, opening the auxiliary valve 53, and placing the left end 51a of the main and auxiliary valve cores 51 onto the main valve seat 10a, closing the main valve 50.

[0074] In addition, when the capacity control valve V is energized, the CS valve core 57 is forced axially to the right by the helical spring 58, and the end face 57a of the CS valve core 57 separates from the CS valve seat 11a of the separation adjustment component 11, and the CS valve 56 opens.

[0075] Next, the non-energized state of the capacity control valve V will be explained. For example... Figure 4 As shown, when the capacity control valve V is not energized, the movable iron core 84 is pressed axially to the right by the force of the helical spring 85, the helical spring 63, and the bellows core 62. As a result, the drive rod 83, the main and auxiliary valve cores 51, and the pressure-sensitive valve component 52 move axially to the right. The axial right end 51b of the main and auxiliary valve cores 51 sits on the auxiliary valve seat 82a, and the axial left end 51a of the main and auxiliary valve cores 51 separates from the main valve seat 10a, and the main valve 50 opens.

[0076] Thus, when the capacity control valve V is de-energized, by opening the main valve 50, the fluid in the discharge chamber 2 of the variable capacity compressor M flows from the discharge chamber 2 into the control chamber 4 via the capacity control valve V. This is because the discharge pressure Pd is higher than the control pressure Pc.

[0077] Furthermore, in the non-energized state of the capacity control valve V, the CS valve core 57 receives the flow of the discharged fluid through the main valve 50 to the Pc port 13 due to the bearing surface 57h. Figure 4 The dynamic pressure generated (shown by a solid arrow in the diagram) presses the CS valve core 57 axially to the left, causing the end face 57a of the CS valve core 57 to sit on the CS valve seat 11a of the separation adjustment member 11, and the CS valve 56 to close. Furthermore, the CS valve 56 is not limited to completely sealing the end face 57a of the CS valve core 57 with the CS valve seat 11a of the separation adjustment member 11; it can also be configured to throttle the flow of fluid from the Pc port 13 to the first Ps port 14.

[0078] In addition, although the illustration is omitted for ease of explanation, it is not limited to the non-energized state of the capacity control valve V. It can also be configured such that when the main valve 50 is slightly open in the intermediate control zone during normal control of the capacity control valve V, the CS valve 56 closes by means of the dynamic pressure of the discharge fluid flowing through the main valve 50 to the Pc port 13.

[0079] Therefore, in the capacity control valve V of this embodiment, during normal operation after the variable capacity compressor M starts, when the main valve 50 is opened, the CS valve 56, by means of the dynamic pressure of the discharged fluid flowing through the main valve 50 to the Pc port 13, overcomes the force of the helical spring 58 and exerts a force on the CS valve core 57 to move it axially to the left. Figure 4(Illustrated with a white arrow in the middle) When CS valve 56 is closed, the control fluid for control pressure Pc is not discharged from the pressure-sensitive chamber 60 through the first Ps port 14. Therefore, the control accuracy of control pressure Pc during normal control is high and the energy efficiency is excellent.

[0080] In addition, due to the through hole 57d provided in the CS valve core 57, the Pc port 13 is always in a state that can communicate with the main valve 50. When the capacity control valve V is not energized, the Pd port 12 and the Pc port 13 are connected when the main valve 50 is open, so that the discharge chamber 2 and the control chamber 4 can be reliably connected.

[0081] In addition, the CS valve 56 is composed of a generally cylindrical CS valve core 57 and a helical spring 58 that applies force to the CS valve core 57 in the valve opening direction, thus enabling a capacity control valve V with the CS valve 56 to be compactly constructed.

[0082] In addition, such as Figure 3 As shown, when the main valve 50 is closed, the CS valve 56 is open, thereby maintaining the control pressure Pc and the suction pressure Ps at the same pressure. Therefore, the control chamber 4 can maintain its maximum capacity to improve operating efficiency. In addition, the pressure of the suction chamber 3 and the control chamber 4 can be balanced and adjusted on the capacity control valve V side, thus eliminating the need for a connecting path or fixed orifice that directly connects the control chamber 4 and the suction chamber 3 of the variable capacity compressor M.

[0083] In addition, the CS valve core 57 has a bearing surface 57h that extends radially in a manner intersecting the flow direction of the discharged fluid, so that dynamic pressure is easily generated by the discharged fluid flowing through the main valve 50 to the Pc port 13 when the main valve 50 is opened.

[0084] Furthermore, the inner diameter of the annular protrusion 57e is formed to be smaller than the outer diameter of the large diameter portion 52b of the stepped cylindrical pressure-sensitive valve component 52, and larger than the outer diameter of the intermediate diameter portion 52c. As a result, the CS valve core 57 can increase the area of ​​the bearing surface 57h while ensuring that the flow path cross-sectional area of ​​the discharged fluid flowing to the Pc port 13 through the inner circumferential surface of the annular protrusion 57e and the outer circumferential surface of the intermediate diameter portion 52c of the pressure-sensitive valve component 52 is sufficient.

[0085] Furthermore, since the CS valve core 57 has an end face 57a that contacts or separates from the CS valve seat 11a of the separation adjustment member 11, when force is applied to the CS valve 56 in the opening direction, the end face 57f on the axially opposite side of the end face 57a abuts against the inner surface of the valve body 10. Thus, the maximum opening area of ​​the CS valve 56 can be set by the abutment between the CS valve core 57 and the inner surface of the valve body 10, thereby simplifying the structure of the CS valve 56.

[0086] In addition, the outer peripheral surface of the CS valve core 57 is guided to the inner peripheral surface of the guide hole 10d of the valve housing 10, so that the CS valve core 57 can stably perform the opening and closing action of the CS valve 56, thus simplifying the structure of the CS valve 56.

[0087] Furthermore, since the capacity control valve V is equipped with a pressure-sensitive valve 54 that opens and closes based on the suction pressure Ps, an intermediate connection path 55 is formed on the main and auxiliary valve cores 51 and the pressure-sensitive valve component 52, enabling the Pc port 13 to connect with the second Ps port 15 through the opening and closing of the pressure-sensitive valve 54. Therefore, when the suction pressure Ps in the intermediate connection path 55 is high, the pressure-sensitive valve 54 opens, and the Pc port 13 connects with the second Ps port 15 via the intermediate connection path 55. Thus, when the variable capacity compressor M starts, the liquid refrigerant in the control chamber 4 can be rapidly discharged into the suction chamber 3. As a result, the variable capacity compressor M exhibits excellent responsiveness during startup.

[0088] In addition, flow paths constituting the opening and closing of the CS valve 56 are respectively provided in the valve housing 10. Figure 3 The first Ps port 14 (illustrated with a solid line arrow) and the second Ps port 15 (omitted) which constitute the flow path opened and closed by the pressure-sensitive valve 54, thereby simplifying the structure of the valve housing 10.

[0089] Example 2

[0090] Next, refer to Figure 5 The capacity control valve of Example 2 will be described. Furthermore, for components identical to those shown in the above examples, the same reference numerals will be used, and repeated descriptions will be omitted.

[0091] The capacity control valve V in Example 2 will be described. For example... Figure 5 As shown, the CS valve core 157 is configured in a generally cylindrical shape and is concentrically arranged on the outer diameter side of the pressure-sensitive body 61 within the pressure-sensitive chamber 60. In addition, a helical spring 158 is externally embedded in the small-diameter mounting portion 157c formed at the axial left end of the CS valve core 157.

[0092] Next, the opening and closing mechanism of the differential pressure valve CS valve 156 will be explained. When the control pressure Pc in the control chamber 4 and the suction pressure Ps in the suction chamber 3 are balanced and equalized, the pressure acting on the CS valve core 157 disposed in the pressure-sensitive chamber 60 from both axial sides is balanced. Therefore, the pressure-bearing areas of the pressure acting on the CS valve 156 in the opening direction (axial right) and closing direction (axial left) are approximately the same, thus offsetting the influence of the pressure acting on the CS valve core 157 from both axial sides. The CS valve core 157 moves axially to the right under the force of the coil spring 158, and the end face 157a of the CS valve core 157 separates from the CS valve seat 11a of the separating adjustment member 11, opening the CS valve 156. Furthermore, in this embodiment, the differential pressure between the control pressure Pc and the suction pressure Ps can also exist within a certain pressure range.

[0093] On the other hand, when the suction pressure Ps in the suction chamber 3 is lower than the control pressure Pc in the control chamber 4, a differential pressure is generated in the axial direction of the CS valve core 157 due to the pressure difference between the control pressure Pc and the suction pressure Ps. The pressure acting on the CS valve core 157 from the left side of the axial direction is less than the pressure acting from the right side of the axial direction, and a force acts on the CS valve core 157 to move it to the left side of the axial direction.

[0094] Therefore, in the capacity control valve V of this embodiment, since the CS valve 156 also serves as a differential pressure valve for the suction pressure Ps and the control pressure Pc, when the main valve 50 is opened, in addition to the dynamic pressure of the discharge fluid flowing to the Pc port 13 through the main valve 50, the CS valve 156 also experiences the differential pressure between the control pressure Pc and the suction pressure Ps in the closing direction, thus enabling the CS valve 156 to operate reliably.

[0095] Furthermore, in the capacity control valve V of this embodiment, when the control chamber 4 is at its maximum capacity, the main valve 50 is closed and the CS valve 156 is open. This allows the control pressure Pc and suction pressure Ps acting on the CS valve core 157 from both axial sides to be balanced, thus offsetting the influence of the pressure acting on the CS valve core 157 from both axial sides and making it easy for the CS valve 156 to open. Therefore, the control chamber 4 can easily maintain its maximum capacity to improve operating efficiency.

[0096] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the specific structure is not limited to these embodiments. Even if changes or additions are made without departing from the spirit of the present invention, they are also included in the present invention.

[0097] For example, in the above embodiment, the pressure-sensitive valve 54, which is composed of pressure-sensitive body 61 and pressure-sensitive valve component 52, may not be provided. In this case, the hollow hole inside the main and auxiliary valve cores 51 that constitute the intermediate connecting path 55 and the second Ps port 15 of the valve body 10 are not required.

[0098] Furthermore, in the above embodiment, it was described that the Pc port 13 is always in a state where it can communicate with the main valve 50 due to the through hole provided in the CS valve core. However, it is not limited to this. It is also possible that the through hole is not provided in the CS valve core, and the communication between the Pc port 13 and the main valve 50 is opened and closed by the operation of the CS valve core, for example.

[0099] Alternatively, in the above embodiments, the secondary valve 53 may not be provided. The axial right end 51b of the main and secondary valve cores 51 only needs to function as a support component to bear axial loads, and does not necessarily need to have a sealing function.

[0100] Alternatively, the CS valve and Pc port 13 can also be located within the second valve chamber 30.

[0101] Alternatively, the second valve chamber 30 may be located on the side opposite to the axial direction of the solenoid 80, and the pressure-sensitive chamber 60 may be located on the side of the solenoid 80.

[0102] In addition, the helical springs 58 and 158 are not limited to compression springs; they can also be tension springs or shapes other than helical.

[0103] Alternatively, the pressure-sensitive body 61 may not use a coil spring internally.

[0104] Symbol Explanation

[0105] 1: Outer shell; 2: Discharge chamber; 3: Suction chamber; 4: Control chamber; 10: Valve body; 10a: Main valve seat; 11: Separation adjustment component; 11a: CS valve seat; 12: Pd port (discharge port); 13: Pc port (control port); 14: First Ps port (suction port); 15: Second Ps port (suction port different from the above); 20: First valve chamber; 30: Second valve chamber; 50: Main valve; 51: Main and auxiliary valve cores (main valve core); 51a: Axial left end; 51b: Axial right end; 52: Pressure-sensitive valve core; 52a: Pressure-sensitive valve seat; 53: Auxiliary valve; 54: Pressure-sensitive valve (pressure-driven valve); 55: Intermediate connecting path; 56: CS valve; 57: CS valve core; 57a: end face; 57f: end face; 57h: bearing surface; 58: helical spring; 60: pressure-sensitive chamber; 61: pressure-sensitive body; 62: bellows core; 63: helical spring; 70: cover; 70a: sealing surface; 80: solenoid; 82: center column; 82a: secondary valve seat; 83: drive rod; 156: CS valve; 157: CS valve core; 157a: end face; 157c: mounting part; 158: helical spring; Pc: control pressure; Pd: discharge pressure; Ps: suction pressure; V: capacity control valve.

Claims

1. A capacity control valve, comprising: The valve body has an outlet for discharge fluid at discharge pressure, an inlet for suction fluid at suction pressure, and a control port for control fluid at control pressure. A rod, driven by a solenoid; and The main valve, consisting of a main valve seat and a main valve core, opens and closes the connection between the discharge port and the control port by moving the rod. A CS valve is provided between the control port and the suction port, which is controlled by the dynamic pressure of the fluid flowing from the discharge port to the control port through the opening of the main valve; The capacity control valve also includes a pressure-driven valve that opens and closes based on the suction pressure. An intermediate connection path is formed on the main valve core, which enables the control port to connect with the suction port by opening and closing the valve driven by the pressure.

2. The capacity control valve according to claim 1, wherein, The control port is always in a state where it can communicate with the main valve.

3. The capacity control valve according to claim 2, wherein, The CS valve has a cylindrical CS valve core and a spring that applies force to the CS valve core in the opening direction.

4. The capacity control valve according to claim 3, wherein, The CS valve core has a bearing surface that extends radially.

5. The capacity control valve according to claim 4, wherein, The CS valve core has an end face that contacts or separates from the CS valve seat. When force is applied to the CS valve in the opening direction, the end face on the opposite side of the axial direction of the end face abuts against the inner surface of the valve body.

6. The capacity control valve according to claim 2, wherein, The CS valve also functions as a differential pressure valve for both intake pressure and control pressure.

7. The capacity control valve according to claim 1 or 2, wherein, The valve housing is provided with an intake port that is different from the intake port that forms the flow path that is opened and closed by the pressure-driven valve.

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