JP2006200435A - Control valve for variable displacement compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve for a variable displacement compressor, which can be used for a compressor with a clutch without greatly modifying a control valve of a clutchless compressor. <P>SOLUTION: Conventional valve rod 15 (a valve rod part 15') and working rod 14 (a working rod part 14') are integrally formed to be a valve rod 16. As a plunger 37 is attracted to an attraction piece 34, a valve body part 15a is moved to the valve closing direction. As the valve rod 16 is pressed downward by a bellows main body 40, the valve body part 15a is moved to the valve opening direction. Even when an electric current value supplied to a coil 32 is nearby zero, a valve opening degree can be continuously changed without causing a step. <P>COPYRIGHT: (C)2006,JPO&NCIPI

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, can be used for a compressor with a clutch without greatly modifying the control valve for a clutchless compressor. The present invention relates to a control valve for a variable displacement compressor.

  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 of Pd is squeezed and led out to the crank chamber, and the lead-out amount (throttle amount) to the crank chamber is controlled according to the suction pressure Ps of the compressor. As can be seen, 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 that can connect / disconnect a rotational driving force transmitted from an engine to a compressor rotating shaft with a clutch and a clutch are not interposed. There is a clutchless compressor in which the rotational driving force of the engine is transmitted to the compressor rotation shaft.

  Here, a conventional example of a control valve for a clutchless compressor is shown in FIG. The illustrated control valve 5 includes a valve rod 15 having a valve body portion 15 a and a valve chamber 21 provided with a valve seat (valve port) 22 to which the valve body portion 15 a comes in contact with and separates from the outer periphery of the valve chamber 21. A plurality of discharge pressure refrigerant introduction ports 25 for introducing a refrigerant having a discharge pressure Pd from the compressor are provided in a portion (upstream side of the valve seat 22), and a compressor crank is provided below the valve seat 22 (downstream side). A valve main body 20 ′ provided with a high-pressure refrigerant supply port 26 communicating with the chamber and an electromagnetic actuator 30 ′ are provided.

  The electromagnetic actuator 30 ′ is a coil 32 having a connector portion 31 ′ for energizing excitation, a cylindrical stator 33 disposed on the inner peripheral side of the coil 32, and press-fitted and fixed to the inner periphery of the lower end portion of the stator 33. A sucker 34 having a concave cross section, a pipe 35 ′ with a flange 35a whose upper end is joined to the outer periphery (step part) of the lower end of the stator 33 by welding, and an inner periphery of the pipe 35 ′ below the attractor 34 A plunger 37 is provided on the side so as to be slidable in the vertical direction, and a cylindrical housing 60 ′ with a bottomed hole is provided 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 main body 20 ′, and the center above the valve chamber including the convex stopper portion 28 is provided. A guide hole 19 through which the valve rod 15 is slidably inserted is formed in the portion. 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 refrigerant introduction ports 27 are formed on the outer periphery thereof, and are introduced from the introduction boat 27 into the introduction chamber 23. The refrigerant having the suction pressure Ps is sensed through the plurality of vertical grooves 37a formed in the outer periphery of the plunger 37, the communication holes 37d formed in the central portion, the communication holes 39 formed in the suction element 34, and the like. It is introduced into the pressure chamber 45.

  A valve closing spring 48 made of a conical compression coil spring for biasing the valve rod 15 upward is disposed at the lower part of the valve body 20 '(high pressure refrigerant supply port 26). Due to the urging force of 48, the upper end portion of the valve stem 15 is always in pressure contact with the plunger 37 (the communication hole 37d portion thereof).

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

  In the control valve 5 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 refrigerant having the suction pressure Ps introduced from the compressor into the suction pressure introduction port 27 passes through the vertical groove 37a formed in the outer periphery of the plunger 37 from the introduction chamber 23, the communication hole 39 formed in the suction element 39, and the like. The bellows body 40 (internally 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). The displacement is transmitted to the valve stem 15 via the actuating rod 14 and the plunger 37, thereby adjusting the valve opening (effective passage cross-sectional area between the valve seat 22 and the valve body portion 15a). That is, the valve opening is determined by the attraction force of the plunger 37 by the solenoid portion comprising the coil 32, the stator 33 and the attraction element 34, the urging force of the bellows body 40, the urging force by the valve opening spring 47 and the valve closing spring 48, In accordance with the valve opening degree, the amount (throttle amount) of the discharge pressure Pd introduced from the discharge pressure refrigerant introduction port 25 into the valve chamber 21 to the refrigerant supply port 26 side, that is, the crank chamber is adjusted. Thus, the pressure Pc in the crank chamber is controlled.

JP-A-2002-303262

  Incidentally, in the control valve 5 for the conventional clutchless compressor as described above, the relationship (control characteristic) between the current value supplied to the coil 32 and the pressure Pc (valve opening) in the crank chamber is shown in FIG. As shown by the broken line in FIG. 4, the current value changes continuously (linearly) as the current value changes from large to small. However, when the current value becomes Ia close to 0, the suction force of the plunger 37 by the suction element 34 decreases. The valve stem 15 is pushed down to the lowest position at a stroke by the valve opening force of the valve opening spring 47, the valve body 15a is fully opened, and the pressure Pc in the crank chamber increases rapidly stepwise. That is, when the current value is Ia or less, the non-control region is set.

  On the other hand, in the control valve for the compressor with a clutch, as shown by the solid line in FIG. 3, the pressure Pc (valve opening) changes continuously (linearly) even when the current value is Ia or less. If control characteristics that can be controlled are required, and the control valve 5 for the clutchless compressor is used as it is, a trouble occurs on the compressor side.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to be used for a compressor with a clutch without greatly modifying a control valve for a clutchless compressor. The object is to provide a control valve for a variable displacement compressor.

  In order to achieve the above object, one of the control valves for a variable displacement compressor according to the present invention is a valve chamber provided with a valve rod having a valve body portion and a valve seat for contacting and separating the valve body portion. A discharge pressure refrigerant introduction port for introducing a refrigerant having a discharge pressure from the compressor upstream from the valve seat, and a high pressure communicating with the crank chamber of the compressor downstream from the valve seat. A valve body provided with a refrigerant supply port, a coil constituting an electromagnetic actuator, a cylindrical stator disposed on the inner peripheral side of the coil, an attractor fixed to the stator, and a lower part of the attractor A plunger arranged slidably in the vertical direction, a pressure sensing chamber formed above the suction element on the inner peripheral side of the stator, and into which the suction pressure of the compressor is introduced, and the pressure sensing chamber A pressure-sensitive response member disposed on the surface, and the pressure-sensitive response member and the plug. An actuating rod disposed between the plunger 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 operation is performed by the pressure sensitive response member. When the rod is pushed downward, the valve body is moved in the valve opening direction.

  The valve rod and the operating rod are integrally formed or integrally connected, and the valve opening is continuously changed without causing a step even when the current value supplied to the coil is close to zero. It is made to be able to do it.

  Another one of the control valves for a variable displacement compressor according to the present invention includes 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 valve body. A discharge pressure refrigerant introduction port for introducing refrigerant at a discharge pressure from the compressor is provided upstream from the seat, and a high-pressure refrigerant supply port communicating with the crank chamber of the compressor is provided downstream from the valve seat. Valve body, a coil constituting an electromagnetic actuator, a cylindrical stator disposed on the inner peripheral side of the coil, an attractor fixed to the stator, and sliding vertically below the attractor Plungers arranged freely, a pressure sensing chamber formed above the suction element on the inner peripheral side of the stator and introduced with the suction pressure of the compressor, and a feeling arranged in the pressure sensing chamber A pressure-responsive member, and is disposed between the pressure-sensitive member and the plunger. When the plunger is attracted to the suction element, the valve body portion is moved in the valve closing direction, and the operating rod is pushed downward by the pressure-sensitive response member. As a result, the valve body portion is moved in the valve opening direction.

  A spring member that biases the plunger upward is provided so that the valve opening can be continuously changed without causing a step even when the current value supplied to the coil is close to zero. It is characterized by being made.

  According to the present invention, since the valve opening can be continuously changed without causing a step even when the current value supplied to the coil is close to 0, the control valve for the clutchless compressor is It can be used as a compressor with a clutch without major modifications, and when producing control valves for both a clutchless compressor and a compressor with a clutch, it is possible to share parts and reduce manufacturing costs. It can be greatly reduced.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an embodiment of a control valve for a variable displacement (with clutch) compressor according to the present invention. In the clutch-equipped compressor control valve 1 shown in FIG. 1, the same reference numerals are given to the portions corresponding to the respective parts of the conventional variable displacement (clutchless) compressor control valve 5 shown in FIG. A duplicate description will be omitted, and the following will focus on the differences.

  In the control valve 1 of the illustrated embodiment, the valve stem 15 (valve stem portion 15 ′) and the actuating rod 14 (actuating rod portion 14 ′) in the conventional example are integrally formed, and this is the valve stem 16. The valve body 20 has a valve chamber 21 provided with a valve seat (valve port) 22 with which the valve body portion 15a of the valve stem 16 contacts and separates, and an outer peripheral portion of the valve chamber 21 (upstream side of the valve seat 22). Are provided with a plurality of discharge pressure refrigerant introduction ports 25 for introducing refrigerant having a discharge pressure Pd from the compressor, and a high pressure refrigerant supply port 26 communicating with the crank chamber of the compressor below the valve seat 22 (downstream side). Is provided.

  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. A pipe-shaped suction element 34, a pipe 35 whose upper end is hermetically joined to the outer periphery (step part) of the lower end of the stator 33 by brazing, and slides up and down on the inner peripheral side of the pipe 35 below the suction element 34. A plunger 37 disposed freely, and a cylindrical housing 60 with a bottomed hole disposed so as to cover the outer periphery of the coil 32 are provided.

  An adjustment screw 65 with a hexagonal hole is screwed onto the top of the stator 33 from the bottom to the top, and between the adjustment screw 65 and the suction element 34 on the inner peripheral side of the stator 33, A pressure-sensitive chamber 45 into which the suction pressure Ps of the compressor is introduced is formed. In the pressure-sensitive chamber 45, a bellows 41, a reverse convex upper stopper 42, and a reverse concave lower A bellows main body 40 including a stopper 43 and a compression coil spring 44 is disposed. Further, the bellows main body 40 is contracted between the bellows main body 40 and the suction element 34 (a direction in which the bellows main body 40 is compressed toward the adjustment screw 65). A compression coil spring 46 is disposed to urge the spring. Further, between the lower stopper 43 (reverse concave portion) of the bellows body 40 and the plunger 37 (recessed portion 37c), a small-diameter operating rod portion 14 'of the valve rod 16 is positioned. A large-diameter member 18 that is slidably fitted into the concave portion 37b and abuts against the bottom portion thereof is caulked and fixed (caulked portion 18a) at the lower end portion of '.

  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 into which the valve stem 16 (the large-diameter valve stem portion 15 ') is slidably inserted is formed. A ring-shaped groove 15b is formed on the outer periphery of the portion of the valve stem 16 (the large-diameter valve stem portion 15 ') that is in sliding contact with the guide hole 19. Further, the upper portion of the valve stem 16 (the large-diameter valve stem portion 15 ′) is inserted into an insertion hole 37 e formed in the lower portion of the plunger 37.

  A suction pressure introduction chamber 23 is formed on the outer periphery of the convex stopper portion 28 in the valve body 20, and a plurality of suction pressure refrigerant introduction ports 27 are formed on the outer periphery thereof. The introduced refrigerant having the suction pressure Ps is introduced into the pressure sensitive chamber 45 through a plurality of vertical grooves 37 a formed on the outer periphery of the plunger 37, operating rod insertion holes 49 formed in the suction element 34, and the like.

  A valve closing spring 48 made of a conical compression coil spring that biases the valve rod 16 upward is disposed at the lower portion of the valve body 20 (high-pressure refrigerant supply port 26). Due to this urging force, the upper end portion of the valve rod 16 (actuating rod portion 14 ′) is always in pressure contact with the lower stopper 43 (the bottom of the reverse recess) of the bellows body 40.

  Further, a ring-shaped connecting body 50 is disposed between the upper end portion of the valve body 20 and the coil 32. At the lower part of the connecting body 50, there is provided a cylindrical portion 50a with a thin wall that is fitted on the outer periphery of the upper portion of the valve body 20, and the connecting body 50 is connected to the valve body 20 by peel caulking the cylindrical portion 50a with a thin wall. Is fixed. Furthermore, the lower end portion of the pipe 35 is hermetically joined to the inner periphery (step portion) of the connecting body 50 by brazing, and the inner peripheral convex portion 50b protruding from the upper end of the connecting body 50 is connected to the housing 60. The bottom portion 61 with a hole is externally fitted and hermetically sealed by brazing. An upper end portion 62 of the housing 60 is caulked and fixed near the upper end portion of the coil 32.

  In the control valve 1 of the present embodiment, the valve opening spring 47 that is present in the control valve 5 for the clutchless compressor of the conventional example does not exist. Further, the valve body portion 15a (the rod-like portion 15c) is slightly thickened so that the effective passage sectional area when fully opened is smaller than that of the conventional example.

  In the control valve 1 having such a configuration, when the solenoid portion including the coil 32, the stator 33, and the attracting element 34 is energized and energized, the plunger 37 is attracted to the attracting element 34. Is moved upward (in the valve closing direction). On the other hand, the refrigerant of the suction pressure Ps introduced from the compressor to the suction pressure introduction port 27 is a longitudinal groove 37a formed in the outer periphery of the plunger 37 from the introduction chamber 23, an operation rod insertion hole 49 formed in the suction element 39, and the like. The bellows 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 increases and expands when the pressure decreases). Then, the displacement is transmitted to the valve rod 16, thereby adjusting the valve opening (effective passage cross-sectional area between the valve seat 22 and the valve body portion 15a). That is, the valve opening degree is determined by the attraction force of the plunger 37 by the solenoid portion comprising 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 closing spring 48, In accordance with the valve opening, the discharge amount Pd introduced into the valve chamber 21 from the discharge pressure refrigerant introduction port 25 is adjusted to the refrigerant supply port 26 side, that is, the amount (throttle amount) to the crank chamber. The pressure Pc in the crank chamber is controlled.

  In this case, in the control valve 1 for the compressor with a clutch according to the present embodiment, the valve rod 15 (valve rod portion 15 ′) and the operating rod 14 (operating rod portion 14 ′) of the conventional control valve 5 for the clutchless compressor. ) Are integrally formed, and this is used as the valve stem 16 and the valve opening spring 47 is removed, so the relationship between the current value supplied to the coil 32 and the pressure Pc (valve opening) in the crank chamber As shown by the solid line in FIG. 3, the control characteristic is such that the pressure Pc (valve opening degree) is continuously increased until the current value changes from large to 0, that is, even when the current value becomes Ia or less. Linear).

  Therefore, the control valve for a clutchless compressor can be used for a compressor with a clutch without making a major modification to it, and both control valves for a clutchless compressor and a compressor with a clutch are produced. In addition, the parts can be shared, and the manufacturing cost can be greatly reduced.

  In the above embodiment, the valve stem 15 (valve stem portion 15 ′) and the actuating rod 14 (actuating rod portion 14 ′) in the conventional example are integrally formed as the valve stem 16. Instead, as shown in FIG. 2, as in the conventional example, the valve rod 15 and the actuating rod 14 are separated, and the valve-opening spring 47 is removed and the play and play of the plunger 37 are eliminated. A compression coil spring 70 as a spring member that biases the plunger 37 upward may be disposed in the introduction chamber 23, and the other configuration may be the same as that of the above embodiment. Also in the control valve 2 for a compressor with a clutch having such a configuration, the valve opening is continuously reduced without causing a step even when the current value supplied to the coil 32 is close to 0, as in the above-described embodiment. Because it can be changed, the control valve for the clutchless compressor can be used for the clutched compressor without any major modifications to it, and control for both the clutchless compressor and the clutched compressor When producing valves, parts can be shared and manufacturing costs can be greatly reduced.

The longitudinal section showing one embodiment of the control valve for variable capacity type compressors concerning the present invention. The longitudinal section showing other embodiments of the control valve for variable capacity type compressors concerning the present invention. The graph which is provided for the comparison explanation of the control characteristic of the control valve for Clares compressors and the control characteristic required for the control valve for compressors with a clutch. The longitudinal cross-sectional view which shows an example of the conventional control valve for variable displacement type (clutchless) compressors.

Explanation of symbols

1, 2 Variable displacement compressor control valve 14 Actuating rod 15 Valve rod 15a Valve body portion 16 Valve rod 18 Large diameter member 20 Valve body 21 Valve chamber 22 Valve seat 25 Discharge pressure introduction port 26 High pressure refrigerant supply port 27 Suction pressure Introducing port 30 Electromagnetic actuator 32 Coil 33 Stator 34 Suction element 35 Pipe 37 Plunger 40 Bellows body 45 Pressure sensitive chamber 48 Valve closing spring 50 Connection body 60 Housing

Claims (2)

  A discharge pressure for introducing a refrigerant having a discharge pressure from a compressor upstream of the valve seat, having a valve chamber provided with a valve rod having a valve body portion and a valve seat to which the valve body portion contacts and separates; A valve body provided with a refrigerant introduction port and provided with a high-pressure refrigerant supply port communicating with the crank chamber of the compressor downstream from the valve seat, a coil constituting an electromagnetic actuator, and an inner peripheral side of the coil A cylindrical stator disposed on the stator, a suction element fixed to the stator, a plunger disposed slidably in the vertical direction below the suction element, and the suction element on the inner peripheral side of the stator A pressure-sensitive chamber that is formed at a higher position and into which the suction pressure of the compressor is introduced; a pressure-sensitive reaction member that is disposed in the pressure-sensitive chamber; and a pressure-sensitive reaction member that is disposed between the pressure-sensitive reaction member and the plunger An actuating rod, and the plunger on the suction element When pulled, the valve body portion moves in the valve closing direction, and when the operating rod is pushed downward by the pressure sensitive member, the valve body portion moves in the valve opening direction accordingly. A control valve for a variable displacement compressor, wherein the valve rod and the actuating rod are integrally formed or integrally connected, and a current value supplied to the coil is close to zero. A variable displacement compressor control valve, wherein the valve opening can be continuously changed without causing a step.   A discharge pressure for introducing a refrigerant having a discharge pressure from a compressor upstream of the valve seat, having a valve chamber provided with a valve rod having a valve body portion and a valve seat to which the valve body portion contacts and separates; A valve body provided with a refrigerant introduction port and provided with a high-pressure refrigerant supply port communicating with the crank chamber of the compressor downstream from the valve seat, a coil constituting an electromagnetic actuator, and an inner peripheral side of the coil A cylindrical stator disposed on the stator, a suction element fixed to the stator, a plunger disposed slidably in the vertical direction below the suction element, and the suction element on the inner peripheral side of the stator A pressure-sensitive chamber that is formed at a higher position and into which the suction pressure of the compressor is introduced; a pressure-sensitive reaction member that is disposed in the pressure-sensitive chamber; and a pressure-sensitive reaction member that is disposed between the pressure-sensitive reaction member and the plunger An actuating rod, and the plunger on the suction element When pulled, the valve body portion moves in the valve closing direction, and when the operating rod is pushed downward by the pressure sensitive member, the valve body portion moves in the valve opening direction accordingly. A control valve for a variable displacement compressor, wherein a spring member for urging the plunger upward is provided, and the valve opening degree even when the current value supplied to the coil is close to 0 A control valve for a variable displacement compressor, wherein the control valve can be continuously changed without causing a step.

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