JP2010185320A - Control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve smoothly and surely moving a plunger in a valve opening direction and quickly and smoothly moving the plunger in a valve closing direction from a fully opened state if energization to an electromagnetic actuator is turned off even when refrigerant pressure works in the valve closing direction. <P>SOLUTION: The control valve includes a first valve opening spring 51 always biasing a valve stem 15 and the plunger 37 in the valve opening direction and is provided with a second valve opening spring 52 which is applied with the refrigerant pressure in the valve closing direction and starts biasing the valve stem 15 and the plunger 37 in the valve opening direction when electric current supplied to the electromagnetic actuator 30 is increased from zero and the valve stem 15 and the plunger 37 are pulled from the fully opened position to a suction element 34 side for a predetermined distance or more against the biasing force of the first valve opening spring 51. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control valve provided with an electromagnetic actuator (solenoid), and more particularly to a control valve suitable for a variable displacement compressor used in a car air conditioner or the like.

  In general, a control valve for a variable displacement compressor used in a car air conditioner or the like introduces a refrigerant having a discharge pressure Pd from a compressor (discharge chamber) in order to adjust a pressure Pc in a crank chamber of the compressor. The refrigerant having the discharge pressure Pd is squeezed out and led to the crank chamber, and the derivation amount (throttle amount) to the crank chamber is controlled according to the suction pressure Ps of the compressor. As seen in Patent Document 1 and the like, various proposals or practical applications using electromagnetic actuators (solenoids) have been made.

  A conventional example of such a control valve for a variable displacement compressor will be briefly described with reference to the schematic configuration diagram of FIG. 8 (for details, refer to Patent Document 1). The illustrated control valve 1 ′ includes a valve stem 15, a valve body 20 that slidably holds the valve stem 15, and an electromagnetic actuator 30.

  The valve rod 15 is composed of a valve rod portion 15A having a valve body portion 16 provided at the lower end portion thereof and an operation rod portion 15B integrally connected to the upper portion thereof.

  The valve body 20 has a valve chamber 21 provided with a valve seat 22 with a valve port 22a to which the valve body portion 16 contacts and separates, and a compressor is provided on the outer peripheral portion of the valve chamber 21 (upstream from the valve port 22a). A discharge pressure refrigerant introduction port 25 for introducing a refrigerant having a discharge pressure Pd is provided, and a refrigerant outlet 26 communicating with the crank chamber of the compressor is provided below (downstream side) of the valve port 22a.

  The electromagnetic actuator 30 includes a coil 32 for energization excitation, a bottomed cylindrical attractor (stator) 34 disposed on the inner peripheral side of the coil 32, and an outer periphery (step) of a lower end portion of the attractor 34. The upper end of the pipe 35 is joined by welding or the like, and a plunger 37 is provided below the suction element 34 and disposed on the inner peripheral side of the pipe 35 so as to be slidable in the vertical direction.

  Further, a pressure sensitive chamber 45 into which the suction pressure Ps of the compressor is introduced is formed in the suction element 34, and a bellows 40 as a pressure sensitive response member is disposed in the pressure sensitive chamber 45. Further, a compression coil spring that constantly biases the valve stem 15 downward (in the valve opening direction) via the plunger 37 is provided between the suction element 34 (the bottom surface thereof) and the plunger 37 (the upper concave portion 37b). The valve opening spring 51 is retracted.

  On the other hand, a convex stopper portion 28 for restricting the lowest position of the plunger 37 protrudes from the upper center of the valve body 20, and the central portion above the valve chamber including the convex stopper portion 28 includes: A guide hole 19 into which the valve stem 15 is slidably fitted is formed. In addition, a suction pressure refrigerant introduction chamber 23 into which a refrigerant having a suction pressure Ps of the compressor is introduced is formed between the plunger 37 and the upper outer periphery (outer periphery of the convex stopper portion 28) of the valve body 20. A plurality of suction pressure refrigerant introduction ports 27 are formed on the outer peripheral side, and the refrigerant of the suction pressure Ps introduced from the suction pressure refrigerant introduction port 27 into the suction pressure refrigerant introduction chamber 23 is between the plunger 37 and the pipe 35. Are introduced into the pressure-sensitive chamber 45 through the through holes 39 formed in the central portion of the suction element 34.

  In the control valve 2 configured as described above, when the solenoid portion including the coil 32, the stator 33, and the attractor 34 of the electromagnetic actuator 30 is energized and energized, the plunger 37 is attracted to the attractor 34. Accordingly, the valve stem 15 is moved upward (in the valve closing direction). On the other hand, the refrigerant having the suction pressure Ps introduced from the compressor into the suction pressure introduction port 27 is communicated with the longitudinal grooves 38, 38,... Formed in the outer periphery of the plunger 37 from the introduction chamber 23 and the suction element 34. The bellows 40 (inside the vacuum pressure) is expanded and contracted according to the pressure (suction pressure Ps) of the pressure sensitive chamber 45 (when the suction pressure Ps is high, it contracts and is low). The displacement is transmitted to the valve stem 15, thereby adjusting the valve opening (the lift amount of the valve body 16).

  That is, the valve opening degree is the refrigerant acting on the valve rod 15 including the valve body portion 16, the suction force of the suction element 34, the biasing force (load) of the bellows 40, the biasing force (load) of the valve opening spring 51. The throttle of the refrigerant of the discharge pressure Pd introduced into the valve chamber 21 from the discharge pressure refrigerant introduction port 25 according to the valve opening degree, which is determined by the pressure (discharge pressure Pd, suction pressure Ps, and crank chamber pressure Pc). The amount, that is, the amount derived to the crank chamber (throttle amount) is adjusted. In other words, the pressure Pc in the crank chamber is controlled according to the valve opening, and accordingly, the inclination angle of the swash plate of the compressor and the stroke of the piston are adjusted to increase or decrease the discharge amount.

Here, in this control valve 1 ′,
Aop: Pressure receiving area of valve stem 15 in the valve opening direction
Fsp: Spring load of the valve opening spring 51
Fbe: Load of bellows 40
Acl: Pressure receiving area of valve stem 15 in the valve closing direction
Assuming that Fso is the suction force of the suction element 34, the balance equation of the force acting in the valve opening direction and the force acting in the valve closing direction is expressed as the following equation (1).
(Pd-Pc)-Aop + Fsp + Fbe = (Pd-Ps)-Acl + Fso (1)
In the above formula (1), the left side is the force acting in the valve opening direction, the right side is the force acting in the valve closing direction, and (Pd−Pc) · Aop is the refrigerant pressure (load) acting in the valve opening direction, (Pd−Ps) Acl is the refrigerant pressure (load) acting in the valve closing direction. In this example, Aop and Acl are substantially equal, and Pc is made larger than Ps, so the refrigerant pressure works in the valve closing direction in the valve. It is like that.

When the energization of the electromagnetic actuator 30 (solenoid) is turned off (suction force Fso = 0), the spring load Fsp of the valve opening spring 51 necessary to move the valve rod 15 and the plunger 37 in the valve opening direction. Is represented by the following equation (2).
Fsp = (Pd-Ps), Acl- (Pd-Pc), Aop-Fbe (2)
From this equation (2), it can be seen that the larger the difference between the crank chamber pressure Pc and the suction pressure Ps, the larger the spring load Fsp of the valve opening spring 51 needs to be.

JP 2008-298013 A

  By the way, in the conventional control valve 1 ′ as described above, when the difference between the crank chamber pressure Pc and the suction pressure Ps is large, in other words, when the refrigerant pressure works in the valve closing direction, the electromagnetic actuator Even if the power supply to 30 is turned off, the load (biasing force) of the valve opening spring 51 is insufficient, and the plunger 37 and the valve stem 15 (valve body portion 16) may not be able to move smoothly in the valve opening direction. There is.

  If the spring load (initial set load) of the valve-opening spring is increased in order to solve this problem, the suction force required to move the valve stem and plunger against the biasing force of the valve-opening spring in the valve closing direction also increases. This increases the size and cost of the electromagnetic actuator.

  This will be described in detail below. First, the relationship of the separation distance (valve lift amount) between the valve body 16 and the valve seat 22 with respect to the current value supplied to the electromagnetic actuator 30 in the control valve 1 ′ of the conventional example (referred to as the conventional example 1), and The relationship of the spring load of the valve-opening spring 51 with respect to the supply current value will be described with reference to FIG. In the control valve 1 ′ (conventional example 1), in the fully open state shown in FIG. 8, the separation distance between the valve body 16 and the valve seat 22, that is, from the fully open state to the fully closed state (the valve body portion 16 is in the valve seat). The lift amount of the valve body portion 16 (valve stem 15) required until the state of contact with 22) is L4.

  Usually, an electromagnetic actuator (solenoid) has a very weak attractive force when the supply current value is close to 0, and does not exhibit a required attractive force unless the current value is increased to some extent. That is, when the current value supplied to the electromagnetic actuator 30 is gradually increased from 0, the attracting force of the attracting element 34 is smaller than the spring load (initial set load) F1 until the current value becomes A1, so that the plunger 37 (and valve stem 15) does not move, and when the current value reaches A1, the suction force becomes larger than the spring load F1, and the plunger 37 starts to move in the valve closing direction against the biasing force of the valve opening spring 51. (Hereinafter, it may be referred to as “activation”.) When the current value becomes A1 or more, the valve opening spring 51 is proportionally compressed as the suction force increases. Therefore, the spring load gradually increases to the right, but when the plunger 37 is activated (current value). In A1), since the separation distance between the valve body 16 and the valve seat 22 is large and the suction force is not stable, the flow rate control cannot be started, the current value becomes A2, and the separation distance becomes L2. Until it becomes, it becomes a non-control area. The separation distance becomes steeply L2 from L4 until the current value becomes A1 to A2, but when the current value exceeds A2, the separation distance gradually decreases, and when the current value is A3, the separation distance is Fully closed or close to L1, and the spring load at this time is F2. A2 is a control start current value, and A2 and subsequent are a control region.

  On the other hand, in the conventional example 2 in which the spring load (initial set load) is increased by, for example, incorporating the valve-opening spring 51 in a compressed state from that of the conventional example 1, as shown in FIG. Since the spring load (initial set load F1 ′, spring load F2 ′ at the current value A3) is considerably larger than that of the conventional example 1, even if the refrigerant pressure works in the valve closing direction, the electromagnetic actuator 30 If the power supply to is turned off, the plunger 37 and the valve stem 15 (valve body portion 16) can be moved smoothly and reliably in the valve opening direction, but the suction force is the spring load (initial set load) F1. The current value that becomes larger (the current value that activates the plunger 37) is A1 'that is larger than A1 in the conventional example 1, and the control start current value is also A2' that is larger than A2 in the conventional example 1. This means that the non-control region is widened and a response delay is likely to occur when the plunger 37 is moved in the valve closing direction from the fully open state where the energization is OFF. In order to make the control start current value equal to that of the conventional example 1, it is necessary to increase the attractive force when starting the plunger 37, which leads to an increase in size and cost of the electromagnetic actuator.

  The present invention has been made in view of the above circumstances, and the purpose of the present invention is to provide a plunger that is turned off when the electromagnetic actuator is turned off, even if the refrigerant pressure works in the valve closing direction. Control that allows the plunger to move smoothly and reliably in the valve opening direction, and allows the plunger to move quickly and smoothly in the valve closing direction from the fully opened state, without increasing the size or cost of the electromagnetic actuator. To provide a valve.

  In order to achieve the above object, a control valve according to the present invention basically includes a valve stem having a valve body portion, a valve body having a valve seat to which the valve body portion comes in contact with and away from, and the valve stem being closed. A coil for energization excitation for driving in the valve direction, an attractor disposed on the inner peripheral side of the coil, an electromagnetic actuator having a plunger disposed opposite to the attractor, the valve stem, and / or Or a first urging means for constantly urging the plunger in the valve opening direction, the fluid pressure is made to act in the valve closing direction, and the supply current value to the electromagnetic actuator is increased from 0, When the valve stem and the plunger are attracted by a predetermined amount or more from the fully open position against the biasing force of the first biasing means, the valve stem and / or the plunger is biased in the valve opening direction. A second urging means for starting to urge is provided.

  A more preferable control valve according to the present invention basically has a valve rod having a valve body portion and a valve chamber provided with a valve seat to which the valve body portion comes into contact with and separates from the compressor, and discharge pressure from the compressor. A discharge pressure refrigerant inlet for introducing a refrigerant is provided upstream of a valve port formed in the valve seat, and a refrigerant outlet communicating with the crank chamber of the compressor is provided downstream of the valve port. An electromagnetic having a valve body, a coil for energizing excitation for driving the valve stem in the valve closing direction, an attractor disposed on the inner peripheral side of the coil, and a plunger disposed to face the attractor A first actuator that constantly biases the valve stem and / or the plunger in the valve-opening direction, and a pressure-sensitive response member that drives the valve stem in the valve opening / closing direction in response to the suction pressure of the compressor. And a refrigerant pressure is exerted in the valve closing direction, The supply current value to the magnetic actuator is increased from 0, and the valve rod and the plunger are attracted by a predetermined amount or more to the attractor side against the biasing force of the first biasing means from the fully opened position. A second urging means is provided to start urging the valve stem and / or plunger in the valve opening direction.

  In a preferred embodiment, the second urging means is interposed between a stationary part such as the suction element and the plunger or the valve rod, and when fully opened, the second urging means is substantially in a no-load state. A separation distance between the working end and the stationary part or the plunger or the valve rod is made shorter than a separation distance between the valve body part and the valve seat.

The first urging means is preferably constituted by a coil spring.
The second urging means is preferably constituted by a coil spring.

The second urging means is preferably composed of an elastic elastic member such as rubber.
The second biasing means is preferably constituted by a washer-like thin plate spring.

  In another preferred embodiment, the second urging means is coaxially arranged on the inner peripheral side or the outer peripheral side of the first urging means.

  In another preferred aspect, the second urging means is disposed at a position separated from the first urging means along the urging direction.

  In a preferred embodiment of the control valve according to the present invention, a first valve opening spring (for example, the above-described conventional example 1) comprising, for example, a compression coil spring as a first urging means for constantly urging the valve rod and the plunger in the valve opening direction In addition to the valve opening spring 51, when the valve stem and the plunger are attracted to the attractor side by a predetermined amount or more from the fully opened position, the valve stem and the plunger start to be urged in the valve opening direction. Since the second valve-opening spring comprising, for example, a compression coil spring is provided as the biasing means, the initial set load is only that of the first valve-opening spring, and the suction force of the suction element is the spring load (initial The current value (current value at which the plunger is activated) larger than the set load) is equivalent to that of Conventional Example 1 described above, and the control start current value is only slightly larger than that of Conventional Example 1. For this reason, since the non-control region is almost the same as the conventional example 1 having only one valve opening spring, there is no response delay as in the conventional example 2 described above, which increases the size and cost of the electromagnetic actuator. Without inviting, the plunger can be moved quickly and smoothly in the valve closing direction from the fully open state.

  In addition, when the valve stem and the plunger are pulled toward the suction element by a predetermined amount or more from the fully opened position, the second valve opening spring starts to urge the valve stem and the plunger in the valve opening direction. The valve rod and plunger are urged in the valve opening direction by a combined spring load that combines the spring load of the first valve opening spring and the spring load of the second valve opening spring. Even if it works, it is possible to move the plunger and the valve stem smoothly and reliably in the valve opening direction by turning off the energization of the electromagnetic actuator.

The schematic block diagram which shows the fully open state of one Embodiment (Example 1) of the control valve which concerns on this invention. The schematic block diagram which shows the fully closed state of the control valve shown by FIG. The schematic block diagram which shows Example 2 of the control valve which concerns on this invention. The schematic block diagram which shows Example 3 of the control valve which concerns on this invention. (A) is a schematic block diagram which shows Example 4 of the control valve based on this invention, (B) shows the washer-like thin plate work spring used for the control valve of (A), (a) is a top view, (B) is XX arrow sectional drawing of (a). The schematic block diagram which shows Example 5 of the control valve which concerns on this invention. The schematic block diagram which shows Example 6 of the control valve which concerns on this invention. The longitudinal cross-sectional view which shows an example of the conventional control valve for variable displacement compressors. The characteristic view with which it uses for description of operation | movement of the conventional and the control valve for variable displacement type compressors of this invention Example, and an effect.

Hereinafter, embodiments of a control valve of the present invention will be described with reference to the drawings.
FIG. 1 and FIG. 2 are schematic configuration diagrams showing a fully open state and a fully closed state, respectively, of an embodiment (Example 1) of a control valve according to the present invention.

  The control valve 1 of the illustrated embodiment 1 is a variable displacement compressor control valve having the same basic configuration as the conventional example 1 shown in FIG. In the variable displacement compressor control valve 1 shown in FIG. 1, portions corresponding to the respective portions of the variable displacement compressor control valve 1 ′ of the conventional example 1 shown in FIG. Thus, the duplicate description is omitted, and in the following, the differences will be mainly described.

  In the control valve 1 of the first embodiment, similarly to the conventional example 1, in the fully opened state shown in FIG. 1, the separation distance between the valve body 16 and the valve seat 22, that is, from the fully opened state to the fully closed state (see FIG. The lift amount of the valve body 16 (valve stem 15) required until the state shown in Fig. 2 is L4.

  In the control valve 1, the first valve-opening spring 51 (conventional example 1 described above) composed of a compression coil spring as a first urging means that constantly urges the valve rod 15 and the plunger 37 in the valve-opening direction. In addition to the valve opening spring 51), when the valve body 16, the valve stem 15, and the plunger 37 are drawn toward the attractor 34 by a predetermined amount or more from the fully opened position (position shown in FIG. 1) A second valve-opening spring 2 comprising a compression coil spring longer than the first valve-opening spring 51 is provided as second biasing means for starting to bias the rod 15 and the plunger 37 in the valve-opening direction.

  The second valve opening spring 52 is coaxially inserted on the outer peripheral side of the actuating rod portion 15B of the valve rod 15 and is inserted into a central recess 37a formed in the plunger 37. ) Is in contact with or fixed to the bottom of the central recess 37a, and the other working end (upper end) is in a no-load (no compression) state when fully open (when the electromagnetic actuator 30 is turned off) A separation distance L3 between the upper end and the lower surface of the suction element 34 is shorter than a separation distance L4 between the valve body 16 and the valve seat 22.

  In the control valve 1 of the present embodiment configured as described above, as shown in FIG. 9C, the initial set load is only F1 of the first valve opening spring 51, and the suction force of the suction element 34 is reduced. The current value (current value at which the plunger is activated) larger than the spring load (initial set load) F1 is A1 which is the same as that in the conventional example 1 described above. When the current value B1 is slightly larger than the current value A1, the separation distance becomes L3, and the upper end of the second valve opening spring 52 comes into contact with the lower surface of the suction element 34, and the second opening degree is determined from the current value B1. When the valve spring 52 starts to be effective and the current value becomes B1 or more, the spring load acting in the valve opening direction of the control valve 1 is the spring load of the first valve opening spring 51 and the spring of the second valve opening spring 52. The combined spring load is combined with the load. In this case, the control start current value at which the separation distance is L2 is only A2 ″, which is slightly larger than that of the conventional example 1. For this reason, since the non-control region is almost the same as the conventional example 1 having only one valve opening spring, there is no response delay as in the conventional example 2 described above, which increases the size and cost of the electromagnetic actuator. Without inviting, the plunger 37 and the valve stem 15 can be moved quickly and smoothly from the fully open state in the valve closing direction.

  Further, when the valve stem 15 and the plunger 37 are attracted to the suction element 34 side by a predetermined amount (L4-L3) or more from the fully opened position, the second valve opening spring 52 moves the valve stem 15 and the plunger 37 in the valve opening direction. Since the biasing starts, in the control region, the valve rod 15 and the plunger 37 are applied in the valve opening direction with a combined spring load obtained by combining the spring load of the first valve opening spring 51 and the spring load of the second valve opening spring 52. Therefore, when the current value is A3, a spring load substantially equal to the spring load F2 ′ of the conventional example 2 in which the initial set load is increased is obtained. Therefore, even if the refrigerant pressure works in the valve closing direction, it is possible to move the plunger 37 and the valve stem 15 smoothly and reliably in the valve opening direction by turning off the power to the electromagnetic actuator 30. It becomes.

  In the second embodiment shown in FIG. 3, the upper end of the second valve opening spring 52 is fixed to the lower surface of the suction element 34 with an adhesive or the like, and the lower end and the bottom of the central recess 37a in the plunger 37 are separated by a distance L3. It has been. Other configurations are the same as those of the first embodiment.

  Even in such a configuration, substantially the same effects as those of the first embodiment can be obtained. Note that the second valve opening spring 52 does not necessarily need to be fixed, and both ends may be arranged in a free state. Also in this case, the second valve-opening spring 52 is substantially unloaded when the electromagnetic actuator 30 is turned off, and one end (or both ends) of the second valve-opening spring 52 and a non-moving portion such as the attractor 34 or the plunger 37. Alternatively, the dimensional shape and the like of each part may be set so that the separation distance (total) from the valve stem 15 is shorter than the separation distance L4 between the valve body 16 and the valve seat 22.

In the third embodiment shown in FIG. 4, both the first valve opening spring and the second valve opening spring are coaxially arranged between the suction element 34 and the valve stem 15, and the valve stem 15 is directly connected. The valve is energized in the valve closing direction. More specifically, an inverted conical compression coil spring is used as the first valve opening spring 53. The first valve opening spring 53 is extrapolated to the small-diameter shaft portion 15c of the valve rod 15, and the lower end thereof is attached to the valve rod 15. A second step consisting of a compression coil spring so as to be received by the upper step (terrace) portion 15e of the actuating rod portion 15B, and so that the actuating rod portion 15B of the valve rod 15 is inscribed in the central recess 37c of the plunger 37. A spring receiving flange 15d is provided for receiving the lower end of the valve opening spring 54. In the fully opened state, the upper end of the second valve opening spring 54 and the lower surface of the suction element 34 are separated by a distance L3 (<L4). Have been to.
In the third embodiment having such a configuration, substantially the same effects as the first and second embodiments can be obtained.

  In the fourth embodiment shown in FIG. 5 (A), a first valve-opening spring 55 made of a compression coil spring is mounted between the lower surface of the suction element 34 and the bottom of the central recess 37a of the plunger 37 so as to provide a washer shape. A second valve opening spring 56 made of a thin plate work spring is attached and fixed to the lower surface of the suction element 34. As shown in FIG. 5B, the second valve-opening spring 56 is formed by punching a thin plate and forming a circular ring having a pair of left and right tongue-shaped bent elastic pieces 56a, 56a. The lower end of the tongue-like bent elastic piece 56a of the second valve opening spring 56 and the upper end of the plunger 37 are separated from each other by a distance L3.

  In the fourth embodiment having such a configuration, substantially the same effects as those of the first to third embodiments can be obtained.

In the fifth embodiment shown in FIG. 6, a rubber elastic elastic member 57 in the form of a circular ring is used in place of the second valve opening spring 56 made of the washer-like thin plate work spring in the fourth embodiment.
In the fifth embodiment, substantially the same effect as that of the fourth embodiment can be obtained.

In the sixth embodiment shown in FIG. 7, the first valve opening spring 51 is similar to the second valve opening spring 56 in order to avoid interference between the first valve opening spring and the second valve opening spring. A second valve opening spring 58 made of a washer-like thin plate work spring having a structure is arranged in the suction element 34 which is a position separated along the urging direction (vertical direction).
In the fifth embodiment, substantially the same effects as in the first to fifth embodiments can be obtained.

1, 2, 3, 4, 5, 6 Variable displacement compressor control valve 15 Valve rod 16 Valve body 20 Valve body 21 Valve chamber 22 Valve seat 22a Valve port 25 Discharge pressure Refrigerant inlet 26 Refrigerant outlet 27 Suction pressure Refrigerant inlet 30 Electromagnetic actuator 32 Coil 34 Suction element 37 Plunger 40 Bellows 45 Pressure sensing chambers 51, 53, 55 First valve opening springs 52, 54 Second valve opening spring 56 Washer-shaped thin plate work spring (second Valve opening spring)
57 Elastic elastic member made of rubber (second urging means)
58 Washer-like thin plate spring (second valve opening spring)
Pd Discharge pressure Ps Suction pressure Pc Crank chamber pressure

Claims (9)

A valve stem having a valve body portion, a valve body having a valve seat to which the valve body portion contacts and separates, a coil for energization excitation for driving the valve stem in a valve closing direction, and an inner peripheral side of the coil And an electromagnetic actuator having a plunger disposed opposite to the suction element, and first biasing means for constantly biasing the valve rod and / or the plunger in the valve opening direction. A control valve in which the fluid pressure works in the valve closing direction,
The supply current value to the electromagnetic actuator is increased from 0, and the valve rod and the plunger are attracted by a predetermined amount or more to the attractor side against the urging force of the first urging means from the fully opened position. And a second urging means for starting to urge the valve rod and / or the plunger in the valve opening direction when provided. A valve rod having a valve body portion and a valve chamber provided with a valve seat for contacting and separating the valve body portion, and a discharge pressure refrigerant inlet for introducing a refrigerant having a discharge pressure from a compressor is formed in the valve seat. A valve body provided upstream of the formed valve port and provided with a refrigerant outlet communicating with the crank chamber of the compressor downstream of the valve port, and for driving the valve rod in the valve closing direction And an electromagnetic actuator having a coil for energization excitation, an attractor disposed on the inner peripheral side of the coil, and a plunger disposed to face the attractor, and in response to the suction pressure of the compressor A pressure sensitive member for driving the valve stem in the valve opening / closing direction; and a first biasing means for constantly biasing the valve rod and / or the plunger in the valve opening direction so that the refrigerant pressure works in the valve closing direction. A control valve for a variable displacement compressor,
The supply current value to the electromagnetic actuator is increased from 0, and the valve rod and the plunger are attracted by a predetermined amount or more to the attractor side against the urging force of the first urging means from the fully opened position. And a second urging means for starting to urge the valve rod and / or the plunger in the valve opening direction when provided.   The second urging means is interposed between a stationary part such as the suction element and the plunger or the valve rod, and when fully opened, the second urging means is substantially in a no-load state. The control valve according to claim 1 or 2, wherein a separation distance between the stationary part or the plunger or the valve rod is shorter than a separation distance between the valve body part and the valve seat.   The control valve according to any one of claims 1 to 3, wherein the first urging means includes a coil spring.   The control valve according to any one of claims 1 to 4, wherein the second urging means includes a coil spring.   The control valve according to any one of claims 1 to 4, wherein the second urging means is made of an elastic elastic member such as rubber.   The control valve according to any one of claims 1 to 4, wherein the second urging means is configured by a washer-like thin plate work spring.   The control according to any one of claims 1 to 7, wherein the second urging means is coaxially arranged on an inner peripheral side or an outer peripheral side of the first urging means. valve.   The said 2nd biasing means is distribute | arranged to the position spaced apart along the biasing direction with respect to the said 1st biasing means, It is any one of Claim 1 to 7 characterized by the above-mentioned. The control valve described.

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