JP2007071049A - Control valve for variable displacement compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve for a compressor with a clutch for providing a required control pressure characteristic while using the control valve for a clutchless compressor and a part in common. <P>SOLUTION: This control valve has a valve rod 15 having a valve element part 15a, a valve body 20 having a valve chest 21 provided with a valve port 22 for contacting and separating the valve element part 15a, arranging a delivery pressure refrigerant inlet 25 on the upstream side of the valve port 22 and arranging a refrigerant outlet 26 communicating with a crankcase of the compressor with the clutch on the downstream side of the valve port 22, an electromagnetic actuator 30 for driving the valve rod 15 in the valve port opening-closing direction, and a pressure sensitive reactive member 40 for driving the valve rod 15 in the opening-closing direction of the valve port 22 in response to suction pressure of the compressor. Pressure Pc becoming Ia or less in an electric current value supplied to a coil 32 of the electromagnetic actuator 30, is set so as not to exceed an allowable pressure value Xc in the compressor with the clutch, and a pressure Pc characteristic exceeding Ia in the electric current value is set in the substantially same as a characteristic of the control valve for the clutchless compressor. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control valve for a variable displacement compressor used in a car air conditioner and the like, and in particular, a clutch capable of connecting and disconnecting a rotational driving force transmitted from an engine to a compressor rotation shaft. The present invention relates to a control valve for a variable displacement compressor suitable for a compressor with a load.

  In general, a compressor used in a car air conditioner uses an engine whose rotational speed varies depending on the situation as a drive source. For this reason, a variable capacity compressor capable of adjusting the refrigerant discharge capacity without being restricted by the engine speed is usually adopted as the car air conditioner compressor.

  The control valve used in such a variable capacity compressor introduces a refrigerant having a discharge pressure Pd from the compressor (discharge chamber) in order to adjust the pressure Pc in the crank chamber of the compressor, and discharge pressure thereof. The refrigerant (flow rate) of Pd is throttled and supplied to the crank chamber, and the supply amount (throttle amount) to the crank chamber is controlled in accordance with the suction pressure Ps of the compressor. As can be seen in Document 1 and the like, various proposals using an electromagnetic actuator (solenoid) have been put to practical use.

  In addition, as a variable capacity compressor used in a car air conditioner, a compressor with a clutch capable of connecting and disconnecting a rotational driving force transmitted from an engine to a compressor rotating shaft with a clutch, and a clutch interposed. There is a clutchless compressor in which the rotational driving force of the engine is directly transmitted to the compressor rotation shaft without any problem.

JP-A-2002-303262

  By the way, the control pressure characteristic of the control valve for the variable displacement compressor, in particular, the control valve for the clutchless compressor provided with an electromagnetic actuator (solenoid) composed of a coil, an attractor, a plunger, etc. is usually shown in FIG. The characteristic is as shown by the broken line. That is, when the current value supplied to the electromagnetic actuator (coil thereof) becomes Ia (for example, 0.1 A) which is close to 0 (energization cut off) or less, the suction force of the plunger by the attractor decreases, and the valve opening spring The valve stem (valve body part) is moved to the maximum lift position at once by the valve opening force, and the valve port where the valve body part comes in contact with and separates is fully opened (the valve opening or the valve lift amount is maximized). Therefore, the flow rate of refrigerant supplied from the refrigerant outlet downstream of the valve port to the crank chamber of the compressor increases at a stroke (maximum flow rate), and the pressure (control pressure) Pc in the crank chamber of the compressor rapidly increases. That is, when the current value is Ia, the control pressure Pc is Xa, but when the current value is smaller than that, the control pressure Pc becomes Xd much higher than the pressure value Xa, and the current value is close to zero. The region (Ia and below) is a non-control region.

  Even if such a non-control region exists, there is no particular problem with the clutchless compressor. However, when the compressor with a clutch enters the non-control region, the pressure Pc in the crank chamber exceeds the allowable pressure value Xc. This causes trouble in terms of control and structure. Therefore, the control valve for a clutchless compressor cannot be used for a compressor with a clutch as it is.

  In other words, the control characteristics required for the control valve for the compressor with the clutch are the same as those for the clutchless compressor in the control region (Ia-Ib) exceeding the current value Ia, as shown by the solid line in FIG. In the non-control region where the current value is Ia or less, the pressure Pc is not higher than the pressure value Xa when the current value is Ia by a predetermined pressure Qs or more (allowable pressure value Xc). Need to be regulated)

  The present invention has been made in view of the above circumstances, and an object thereof is to obtain required control pressure characteristics while sharing parts with a control valve for a clutchless compressor. The object is to provide a control valve for a compressor with a clutch.

  In order to achieve the above object, a control valve for a variable displacement compressor according to the present invention is a clutch-equipped compressor that is capable of connecting and disconnecting a rotational driving force transmitted to a compressor rotating shaft with a clutch. Used to control the pressure (Pc) of the crank chamber of the compressor, comprising a valve rod having a valve body portion and a valve chamber provided with a valve port for contacting and separating the valve body portion. A valve main body provided with one or a plurality of discharge pressure refrigerant inlets upstream from the valve opening, and provided with a refrigerant outlet communicating with the crank chamber of the compressor downstream from the valve opening; And an electromagnetic actuator for driving the valve stem in the valve opening / closing direction, and a pressure sensitive responsive member for driving the valve stem in the valve opening / closing direction in response to the suction pressure of the compressor.

  The pressure (Pc) in the non-control region where the current value supplied to the coil of the electromagnetic actuator is equal to or less than the predetermined value (Ia) does not exceed the allowable pressure value (Xc) in the compressor with a clutch. In order to achieve this, there is provided a throttle mechanism for regulating the flow rate of the refrigerant guided from the refrigerant inlet to the valve port, and the pressure (Pc) characteristic in the control region where the current value exceeds the predetermined value (Ia). The maximum lift amount of the valve body portion from the valve port is set so as to be substantially the same as the characteristic in the state where the throttle mechanism is not provided.

  More specifically, the control valve for a variable displacement compressor according to the present invention has a valve rod having a valve body part, and a valve chamber provided with a valve port for contacting and separating the valve body part, One or a plurality of discharge pressure refrigerant inlets for introducing refrigerant at a discharge pressure from the compressor upstream from the valve port, and a refrigerant communicating with the crank chamber of the compressor downstream from the valve port A valve body provided with an outlet, a coil, a cylindrical stator disposed on the inner peripheral side of the coil, an attractor fixed to the stator, and slidable vertically below the attractor An electromagnetic actuator having a distributed plunger, a pressure sensing chamber formed above the suction element on the inner peripheral side of the stator and into which suction pressure is introduced from the compressor, and arranged in the pressure sensing chamber A pressure-sensitive response member, and the pressure-sensitive response member and the plunger And when the plunger is attracted to the suction element, the valve body portion is moved in the valve closing direction, and the pressure sensitive response member pushes the operation rod. When moved, the valve body portion is moved in the valve opening direction.

  The pressure (Pc) in the non-control region where the current value supplied to the coil of the electromagnetic actuator is equal to or less than a predetermined value (Ia) exceeds the allowable pressure value (Xc) in the compressor with a clutch. In order to prevent the pressure (Pc) characteristic in a control region in which a throttle mechanism for regulating the flow rate of the refrigerant guided from the refrigerant inlet to the valve port is provided and the current value exceeds the predetermined value (Ia). However, the maximum lift amount of the valve body portion from the valve port is set so as to be substantially the same as the characteristic in a state where the throttle mechanism is not provided.

The throttling mechanism is preferably composed of an orifice communicating the refrigerant inlet and the valve port.
In this case, in a preferred embodiment, a pair of left and right refrigerant inlets are provided, and the pair of refrigerant inlets and the valve ports are respectively communicated by orifices.

  In the control valve for a variable displacement compressor according to the present invention, the pressure at the non-control region where the current value is Ia or less does not exceed the allowable pressure value Xc in the compressor with a clutch. An orifice is formed between the valve port and the refrigerant flow rate (discharge pressure Pd) guided to the valve port is reduced, and the pressure Pc characteristic in the control region where the current value exceeds Ia is the characteristic of the control valve for the clutchless compressor. Since the maximum lift amount from the valve port of the valve body is set so as to be substantially the same as the characteristics, the control pressure characteristics required for the compressor with a clutch can be obtained.

  In addition, since it is only necessary to make some modifications to the control valve for the clutchless compressor, most of the parts can be shared when producing control valves for both the clutchless compressor and the compressor with the clutch. Manufacturing costs can be kept low.

Hereinafter, embodiments of a control valve for a compressor of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a control valve for a compressor with a clutch according to the present invention.
The illustrated control valve 1 for a compressor with a clutch is obtained by slightly modifying the control valve for a clutchless compressor, and most of the parts are the same as those for a clutchless compressor. The configuration will be described in detail below.

  The control valve 1 is a valve chamber 21 provided with a valve rod 15 provided with a cross-sectional or T-shaped valve body 15a at the lower end and a valve port (valve seat) 22 through which the valve body 15a contacts and separates. Discharge pressure refrigerant inlets 25 and 25 with a pair of left and right filters 49 for introducing a refrigerant having a discharge pressure Pd from the compressor are provided on the outer peripheral portion (upstream side of the valve port 22) of the valve chamber 21. And a valve body 20 provided with a refrigerant outlet 26 communicating with the crank chamber of the compressor below the valve port 22 (downstream side), and an electromagnetic actuator 30.

  In this embodiment, as will be described in detail later, the pair of left and right refrigerant inlets 25 and 25 and the valve port 22 are provided to regulate the flow rate of the refrigerant introduced from the refrigerant inlets 25 and 25 to the valve port 22. They are communicated with each other through orifices 80 and 80 as throttle mechanisms.

  The electromagnetic actuator 30 includes a coil 32 having a connector portion 31 for energization excitation, a cylindrical stator 33 disposed on the inner peripheral side of the coil 32, and a concave section that is press-fitted and fixed to the inner periphery of the lower end portion of the stator 33. Pipe-shaped suction element 34, pipe 35 with flange 35a whose upper end is joined to the outer periphery (stepped part) of the lower end of stator 33 by welding, and vertically below the suction element 34 on the inner peripheral side of pipe 35 And a plunger housing 37 slidably disposed on the bottom of the coil 32 and a cylindrical housing 60 with a bottomed hole disposed so as to cover the outer periphery of the coil 32.

  Further, an adjusting screw 65 having a hexagonal hole is screwed onto the stator 33, and a suction pressure Ps of the compressor is interposed between the adjusting screw 65 and the suction element 34 on the inner peripheral side of the stator 33. Is formed in the pressure sensing chamber 45. The pressure sensing chamber 45 includes a bellows 41, a reverse convex upper stopper 42, a reverse concave lower stopper 43, and a compression coil. A bellows body 40 comprising a spring 44 is disposed, and further, a compression coil that urges the bellows body 40 and the suction element 34 in a direction in which the bellows body 40 contracts (a direction in which the bellows body 40 is compressed toward the adjustment screw 65). A spring 46 is disposed. Also, a stepped operating rod 14 that passes through the suction element 34 is disposed between the lower stopper 43 (reverse concave part thereof) of the bellows body 40 and the plunger 37 (recessed part 37c thereof). A valve-opening spring 47 made of a compression coil spring that biases the valve rod 15 downward (in the valve-opening direction) via the plunger 37 is disposed between the valve 34 and the plunger 37 (the recess 37b).

  On the other hand, a convex stopper portion 28 for restricting the lowest position of the plunger 37 protrudes above the valve chamber 21 in the valve body 20, and a central portion above the valve chamber including the convex stopper portion 28. A guide hole 19 through which the valve rod 15 is slidably inserted is formed. In addition, a suction pressure introduction chamber 23 is formed on the outer periphery of the convex stopper portion 28, and a plurality of suction pressure inlets 27 are formed on the outer periphery thereof, and the suction introduced into the introduction chamber 23 from the inlet 27. The pressure Ps is transmitted through the longitudinal grooves 37a, 37a,... Formed in the outer periphery of the plunger 37, the communication hole 37d formed in the central portion, the communication hole 39 formed in the suction element 34, and the like. To be introduced.

  Further, in the refrigerant outlet 26 provided at the lowermost part of the valve body 20, a conical compression in which the valve rod 15 is urged upward and the upper end thereof is pressed against the plunger 37 (the communication hole 37 d portion thereof). A valve closing spring 48 made of a coil spring is disposed.

  A lower end flange 35a of the pipe 35 is placed on the upper end of the valve body 20 via an O-ring 57, and a short cylindrical shape with a flange 56a is provided between the flange 35a and the coil 32. The pipe holder 56 is interposed, and the hook-like portions 35 a and 56 a are fastened and fixed together by the upper end outer periphery caulking portion 29 of the valve body 20. Further, the bottom portion 61 with a hole of the housing 60 is press-fitted and fixed to the upper end portion of the pipe holder 56, and the upper end portion 62 of the housing 60 is caulked and fixed on the flange-shaped portion 31 c of the connector portion 31. An O-ring 66 is interposed between the connector part 31 and the coil 32. A concave portion 31a is formed at the lower center of the connector portion 31. The concave portion 31a is formed with a convex portion 31b fitted into the hexagonal hole of the adjusting screw 65. The stator 33 and the adjusting screw are formed in the concave portion 31a. The upper part of 65 is inserted.

  In the control valve 1 having such a configuration, when the solenoid portion including the coil 32, the stator 33, and the attractor 34 is energized and energized, the plunger 37 is attracted to the attractor 34. Is moved upward (in the valve closing direction) by the urging force of the valve closing spring 48. On the other hand, the suction pressure Ps introduced from the compressor into the suction pressure inlet 27 passes through the longitudinal grooves 37a, 37a,... Formed in the outer periphery of the plunger 37 from the introduction chamber 23, the communication holes 39 formed in the suction element 34, and the like. The bellows main body 40 (inside the vacuum pressure) is expanded and contracted according to the pressure in the pressure sensitive chamber 45 (suction pressure Ps) (contracts when the suction pressure Ps is high and expands when the pressure is low). Then, the displacement is transmitted to the valve stem 15 via the operating rod 14 and the plunger 37, and thereby the valve opening degree (the lift amount from the valve opening 22 of the valve body portion 15 a), in other words, the outflow from the valve opening 22. The refrigerant flow rate to be adjusted is adjusted. That is, the refrigerant flow rate is determined by the attraction force of the plunger 37 by the solenoid portion including the coil 32, the stator 33, and the attraction element 34, the urging force of the bellows body 40, and the urging force by the valve opening spring 47 and the valve closing spring 48. It is determined.

  Here, in this embodiment, in order to regulate the flow rate of the refrigerant guided from the refrigerant inlets 25 and 25 to the valve port 22, the pair of left and right refrigerant inlets 25 and 25 and the valve port 22 each have a hole diameter as a throttle mechanism. The orifices 80 and 80 of d are connected to each other.

  In this way, by forming the orifices 80 and 80 between the refrigerant inlets 25 and 25 and the valve port 22 to reduce the flow rate of refrigerant (discharge pressure Pd) guided to the valve port 22, a two-dot chain line in FIG. Control pressure characteristics as shown are obtained.

  That is, as shown in FIG. 3, the opening diameter of the refrigerant inlets 25, 25 is D, and the refrigerant flow rate (discharge pressure Pd) guided from the inlets 25, 25 to the valve port 22 is not substantially reduced. In the control valve 1 ′ for the clutchless compressor thus configured, as indicated by a broken line in FIG. 4 (the same as the broken line in FIG. 5 described above), the current value supplied to the coil 32 of the electromagnetic actuator 30 Is less than Ia (e.g., 0.1 A) close to 0 (energization cut off), the crank chamber pressure (control pressure) Pc becomes Xd much higher than the pressure value Xa at the current value Ia, whereas the refrigerant By forming orifices 80 and 80 between the inlets 25 and 25 and the valve port 22 to reduce the refrigerant flow rate (discharge pressure Pd) guided to the valve port 22, as shown by a two-dot chain line in FIG. The current value becomes Ia or less In the non-control region, the pressure Pc is suppressed to a pressure value Xb that is a predetermined pressure Qs higher than the pressure value Xa when the current value is Ia, and smaller than the allowable pressure value Xc in the compressor with a clutch. In the non-control region, the characteristics required for the control valve for the compressor with a clutch can be satisfied.

  However, if the orifices 80 and 80 are formed between the refrigerant inlets 25 and 25 and the valve port 22 as described above and the refrigerant flow rate (discharge pressure Pd) guided to the valve port 23 is reduced, the control exceeds the current value Ia. In the region (Ia-Ib), the pressure Pc becomes lower than the characteristics required for the clutch-equipped compressor control valve indicated by the solid line in FIGS. 4 and 5 (the same characteristics as those for the clutchless compressor).

  Therefore, in the control valve 1 for a compressor with a clutch of the present embodiment, the pressure Pc characteristic in the control region is in a state where the throttle mechanism (orifices 80, 80) is not provided, that is, the clutch shown in FIG. The maximum lift amount La from the valve port 22 of the valve body 15a is set so as to be substantially the same as the characteristics of the control valve 1 ′ for the less compressor.

  Specifically, the hole diameters d of the pair of left and right orifices 80 and 80 are set to 0.83 to 0.85 mm, respectively, and the maximum lift amount La is set to 0.15 to 0.25 mm. Incidentally, in the clutchless compressor control valve 1 ′ shown in FIG. 3, the maximum lift Lb is, for example, 0.6 mm.

  The refrigerant inlet 25 and the orifice 80 may be only one instead of the left and right pair (two) as described above. In this case, the effective passage cross-sectional area is substantially the same as that of the two. In addition, the hole diameter d of the orifice is preferably 1.10 to 1.20 mm.

  In the control valve 1 for a compressor with a clutch of this embodiment having such a configuration, the pressure Pc in the non-control region where the current value is Ia or less does not exceed the allowable pressure value Xc in the compressor with a clutch. Therefore, orifices 80, 80 are formed between the refrigerant inlets 25, 25 and the valve port 22 to reduce the flow rate of refrigerant (discharge pressure Pd) guided to the valve port 22, and the current value exceeds Ia. Since the maximum lift amount from the valve port 22 of the valve body portion 15a is set so that the pressure Pc characteristic at the point is substantially the same as the characteristic of the control valve 1 ′ for the clutchless compressor, the solid line in FIG. The control pressure characteristics required for a compressor with a clutch as shown in FIG.

  In addition, since it is only necessary to make some modifications to the control valve for the clutchless compressor, most of the parts can be shared when producing control valves for both the clutchless compressor and the compressor with the clutch. Manufacturing costs can be kept low.

The longitudinal cross-sectional view which shows one Embodiment of the control valve for compressors with a clutch which concerns on this invention. The expanded longitudinal cross-sectional view of the valve chamber periphery used for description of the control valve for compressors with a clutch shown by FIG. The expanded longitudinal cross-sectional view of the valve chamber periphery used for description of the control valve for clutchless compressors. The graph which shows the relationship between the pressure Pc and an electric current value used for description of operation | movement of the control valve for compressors shown in FIG. 1, an effect | action, and an effect. The graph which shows the relationship between the pressure Pc and an electric current value used for operation | movement description of the conventional control valve for clutchless compressors, and the control valve for compressors with a clutch.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control valve 14 for a compressor with a clutch Actuating rod 15 Valve rod 15a Valve body part 16 Valve rod 18 Large diameter member 20 Valve main body 21 Valve chamber 22 Valve port 25 Discharge pressure refrigerant inlet 26 Refrigerant outlet 27 Suction pressure inlet 30 Electromagnetic actuator 32 Coil 33 Stator 34 Suction element 35 Pipe 37 Plunger 40 Bellows body 45 Pressure sensing chamber 48 Valve closing spring 50 Connection body 60 Housing 80 Orifice

Claims (4)

Clutch used in a clutch-equipped compressor capable of connecting / disconnecting the rotational driving force transmitted to the rotary shaft of the compressor with a clutch, and controlling the pressure (Pc) of the crank chamber of the compressor A control valve for a compressor,
A valve rod having a valve body portion and a valve chamber provided with a valve port for contacting and separating the valve body portion; and one or a plurality of discharge pressure refrigerant inlets are provided upstream from the valve port. A valve body provided with a refrigerant outlet communicating with the crank chamber of the compressor downstream from the valve port, an electromagnetic actuator for driving the valve rod in the valve port opening / closing direction, and a suction of the compressor A pressure-sensitive responsive member that drives the valve stem in a valve opening / closing direction in response to pressure,
The pressure (Pc) in the non-control region where the current value supplied to the coil of the electromagnetic actuator is not more than a predetermined value (Ia) does not exceed the allowable pressure value (Xc) in the compressor with a clutch. Therefore, a throttle mechanism that regulates the flow rate of the refrigerant guided from the refrigerant inlet to the valve port is provided, and the pressure (Pc) characteristic in a control region where the current value exceeds the predetermined value (Ia) is A control valve for a compressor with a clutch, wherein a maximum lift amount from the valve port of the valve body portion is set so as to be substantially the same as a characteristic in a state where the throttle mechanism is not provided. . Clutch used in a clutch-equipped compressor capable of connecting / disconnecting the rotational driving force transmitted to the rotary shaft of the compressor with a clutch, and controlling the pressure (Pc) of the crank chamber of the compressor A control valve for a compressor,
A valve rod having a valve body portion and a valve chamber provided with a valve port for contacting and separating the valve body portion, and one for introducing a refrigerant having a discharge pressure from a compressor upstream from the valve port Alternatively, a valve body provided with a plurality of discharge pressure refrigerant inlets and a refrigerant outlet communicating with the crank chamber of the compressor on the downstream side of the valve opening, and a coil, and disposed on the inner peripheral side of the coil An electromagnetic actuator having a cylindrical stator, a suction element fixed to the stator, and a plunger slidably arranged in the vertical direction below the suction element, and an inner periphery side of the stator A pressure-sensitive chamber formed above the suction element and into which suction pressure is introduced from the compressor; a pressure-sensitive response member disposed in the pressure-sensitive chamber; and a space between the pressure-sensitive response member and the plunger. An actuating rod disposed on the suction element, When the actuator is pulled, the valve body portion moves in the valve closing direction, and when the operating rod is pushed by the pressure sensitive member, the valve body portion moves in the valve opening direction. Is supposed to
The pressure (Pc) in the non-control region where the current value supplied to the coil of the electromagnetic actuator is not more than a predetermined value (Ia) does not exceed the allowable pressure value (Xc) in the compressor with a clutch. Therefore, a throttle mechanism for restricting the flow rate of refrigerant guided from the refrigerant inlet to the valve port is provided, and the pressure (Pc) characteristic in a control region where the current value exceeds the predetermined value (Ia) is A control valve for a compressor with a clutch, wherein a maximum lift amount from the valve port of the valve body portion is set so as to be substantially the same as a characteristic in a state where the throttle mechanism is not provided. .   3. The control valve for a compressor with a clutch according to claim 1, wherein the throttle mechanism includes an orifice that communicates the refrigerant inlet and the valve opening. 4.   4. The control valve for a compressor with a clutch according to claim 3, wherein a pair of left and right refrigerant inlets are provided, and the pair of refrigerant inlets and the valve ports are respectively connected by orifices.

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