JP3993737B2 - Control valve for variable capacity compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control valve for a variable capacity compressor, and more particularly to a pressure receiving member used for this type of control valve.
[0002]
[Prior art]
For example, in an automotive air conditioner, a compressor (compressor) constituting the refrigeration cycle is driven by being directly connected to an automobile engine with a belt or the like. Therefore, adjustment of the cooling capacity required in the refrigeration cycle cannot be performed by controlling the rotation speed of the compressor. Therefore, in this type of refrigeration cycle, a variable capacity compressor is used that can adjust the cooling capacity by changing the discharge amount of the refrigerant without being restricted by the rotational speed of the engine.
[0003]
As shown in FIG. 1, this type of variable capacity compressor 40 is, for example, tilted by rotating a tilting plate 42 having a variable tilt angle in an airtight crank chamber 41 around a rotating shaft 43. Exercise. The refrigerant in the suction chamber 46 is sucked into the cylinder 45 by the piston 44 reciprocating in conjunction with the tilting motion, compressed in the cylinder 45, and then discharged into the discharge chamber 47. The refrigerant discharge amount is changed by changing the tilt angle of the tilt plate 42 in accordance with the difference between the pressure in the crank chamber 41 and the pressure in the suction chamber 46.
[0004]
By the way, the compressor 40 uses a device called a control valve in order to change the amount of refrigerant by changing the inclination angle of the tilting plate 42 according to the pressure difference as described above. An example of this type of control valve is described in Japanese Utility Model Publication No. 64-27487. Here, the electromagnetic drive unit of the variable capacity compressor is, for example, a plunger via a pressure receiving member provided between a plunger driven in a predetermined direction by the action of a solenoid by an external signal and a control valve unit. The valve part which contacts is driven.
[0005]
Conventionally, in this type of control valve for a variable capacity compressor, for example, a bellows or a metal diaphragm has been used as the pressure receiving member.
[0006]
[Problems to be solved by the invention]
However, the conventional variable displacement compressor control valve has the following drawbacks. First, when a bellows is used as a pressure receiving member, the structure becomes complicated, which is inevitably expensive and causes high costs. In addition, when a metal diaphragm is used, the diaphragm itself has a large rigidity and a large spring constant. Therefore, it is difficult to smoothly transmit the movement of the valve section in the control valve section to the electromagnetic drive section, and the operating characteristics are reduced. It had the problem of causing variation.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a control valve having stable characteristics with little variation in operation characteristics of valve operation by an electromagnetic drive section.
[ 0008 ]
[Means for Solving the Problems]
The present invention relates to a valve portion for controlling the pressure in the crank chamber of the compressor, an operating rod that opens and closes in conjunction with the valve portion, a valve that receives the pressure in the suction chamber of the compressor and operates in conjunction with the operating rod. In a control valve having a pressure receiving member for regulating the movement of the part and an electromagnetic driving part for regulating the opening / closing operation of the valve part in conjunction with the operating rod, the diaphragm as the pressure receiving member has a thickness of about 0.05 mm. A polyimide sheet and a waterproof material made of Teflon coating or Teflon sheet are laminated on one side of the polyidiimide sheet on the side in contact with the disc-like disk operated by the plunger driven in the axial direction by the operation of the electromagnetic drive unit. The peripheral portion of the contact surface between the plunger driven by the electromagnetic drive unit and the pressure receiving member is a curved surface (curvature radius: m) of 0.3 to 2.0. Et al, the flexure gap of the pressure receiving member by the driving of the plunger, characterized in that a 1 to 1.2 mm.
[0009]
In addition, the pressure receiving member according to the present invention is characterized in that at least one surface is waterproofed. Further, the pressure receiving member has a two-layer structure of a synthetic resin material (for example, a polyimide sheet) and a waterproof material (for example, a Teflon sheet). In this case, preferably, the waterproof material is disposed on the control valve portion side.
[0010]
Further, a peripheral portion R (curvature radius: m) of a contact surface between the plunger driven by the electromagnetic drive unit according to the present invention and the pressure receiving member is a curved surface of 0.3 to 2.0. And Moreover, it is preferable that the bending portion gap of the pressure receiving member driven by the plunger is 0.8 to 4.0 mm.
[0011]
In the control valve according to the present invention, the rigidity of the pressure receiving member can be reduced by using a synthetic resin diaphragm as the pressure receiving member. For this reason, the operation characteristics of the electromagnetic drive unit are stable with little variation.
[0012]
Further, when polyimide is used as the synthetic resin material, polyimide is vulnerable to moisture and vapor. For this reason, the strength easily deteriorates due to moisture or steam generated in the refrigeration cycle. Therefore, it is possible to prevent strength deterioration due to moisture, etc. by applying waterproof treatment to the polyimide surface or attaching a waterproof sheet to at least one side of the polyimide sheet, significantly extending the life of the diaphragm and improving durability. Is possible.
[0013]
Further, the contact characteristics between the plunger 23 driven by the magnetic circuit constituting member 32 or the electromagnetic drive unit and the pressure receiving member 35 are set in the above range, or the bending portion gap of the pressure receiving member is set in the above range. Can be further improved. That is, the hysteresis is small and the pressure resistance can be ensured. In this case, if the gap between the upper end inner surface of the magnetic circuit constituting member 32 or the outer peripheral surface of the plunger 23 and the pressure receiving member 35 is too small, the hysteresis is increased, and if the gap is too large, the pressure resistance is reduced. Become.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a control valve for a variable capacity compressor according to the present invention will be described. A control valve M for a variable capacity compressor shown in FIGS. 1 and 2 includes a control valve unit 1 and an electromagnetic drive unit 2. ing.
[0015]
The control valve unit 1 includes a valve main body 11, a filter 12 for removing foreign matter such as iron scrap and dust, an operating rod 13, a disk-shaped disk 14, a spring support 15, a spring 16, and a ball. It consists of a valve portion 17 such as a valve. Here, in the valve body 11, the first communication passage 6 that communicates with the discharge chamber 47 in use, the second communication passage 7 that communicates with the crank chamber 41, and the third communication passage that communicates with the suction chamber 46. The communication passages 8 are respectively formed at the illustrated positions. Furthermore, a fourth communication passage 9 communicating with the first communication passage 6, the second communication passage 7, and the third passage connection 8 is formed in the center of the valve body 11 in the axial direction. A valve port 18 that is opened and closed by the valve portion 17 is provided at the upper end of the communication passage 9.
[0016]
The operating rod 13 and the disk 14 are connected by fitting the end of the operating rod 13 into a recess formed in the disk. Further, the other end of the operating rod 13 is inserted into the fourth communication passage 9 located on the upper side of FIG. 1 so as to be movable up and down, and the upper end of the operating rod 13 is a valve portion for opening and closing the valve port 18. 17 abuts from below. The valve portion 17 is operated via a pressure receiving member 35 and an operating rod 13 which will be described later by a plunger 23 which is driven in the axial direction by the operation of an electromagnetic driving portion 2 which will be described later.
[0017]
In the hollow portion 30 provided in the axial direction inside the main body portion 20 constituting the electromagnetic drive portion 2, there is a metal sleeve 21, and the outside of the bobbin 22 a having flanges on both sides outside the sleeve. A solenoid 22 wound around a coil, a plunger 23 accommodated in the sleeve so as to be movable back and forth in the axial direction, a cylindrical core 24 positioned below the plunger, and one end thereof. An operating rod 25 inserted into the plunger 23 and inserted into the core 24 is accommodated.
[0018]
A support hole 30a for supporting the lower end of the operating rod 25 is provided in the hollow portion 30, and a retaining ring 26 is attached to an intermediate portion of the operating rod 25, and between the inner end wall 30b of the hollow portion and the retaining ring 26 is provided. The spring 27 is bulleted. Further, the connector part 3 in which one end of the connection terminal 28 for supplying power to the solenoid 22 is disposed in the recess 29 and the main body part 20 are integrally formed, and the other end of the connection terminal is the outer periphery of the bobbin 22a. Is connected to a coil wound around.
[0019]
A disc-shaped plate 33 forming a part of a magnetic circuit constituent member is attached between the solenoid 22 provided in the main body portion 20 and the connector portion 3, and the outside of the solenoid 22 is made of a magnetic material. The electromagnetic drive unit 2 is configured by covering with the member 32 and caulking the periphery of the plate 33 with the lower end of the component member 32.
[0020]
At the center of the magnetic circuit constituting member 32, the plunger 23 protrudes from an internal opening 30c provided with substantially the same diameter as the sleeve 21. Further, a pressure receiving member 35 that also serves as a seal member is interposed between the upper surface of the magnetic circuit constituent member 32 and the control valve portion 1, and an upper peripheral edge portion of the circuit constituent member 32 is provided at the lower end portion of the valve body 11. Squeeze out. Reference numeral 36 denotes a sealing material that hermetically seals between the pressure receiving member 35 and the electromagnetic driving unit 2. The plunger 23 functions as a driving body by the operation of the solenoid 22.
[0021]
In a state where no power is supplied to the solenoid 22, the plunger 23 moves upward in FIG. 1 due to the elastic force of the spring 27, and the end of the disk 14 abuts on the valve body 11 via the pressure receiving member 35, The valve portion 17 is pushed upward at the upper end of the operating rod 13 to open the valve port 18. Thus, when the solenoid 22 is inoperative, the plunger 23 is moved upward by the spring 27, and the pressure receiving member 35 is bent upward and deformed in FIG.
[0022]
On the other hand, when power is supplied to the solenoid 22 to drive it, the plunger 23 is driven downward in FIG. 2 by the action of the solenoid against the elastic force of the spring 27. When the load from the plunger 23 disappears, the actuating bar 13 pushes the valve portion 17 downward by the spring force of the spring 16 to close the valve port 18. As described above, the valve portion 17 functions to open and close the communication between the discharge chamber 47 and the crank chamber 41.
[0023]
The pressure receiving member 35 partitions the disk 14 and the plunger 23 in a state where the control valve unit 1 and the electromagnetic drive unit 2 are combined as shown in FIGS. And this pressure receiving member 35 is comprised from the polyimide which consists of synthetic resin materials. Specifically, it is made from a polyimide sheet having a thickness of about 0.05 mm. Preferably, a Teflon coating is applied to the upper side of the polyimide sheet in FIG. Or the disk 14 side of the polyimide sheet may have a structure in which Teflon sheets are laminated.
[0024]
By laminating a Teflon coating or a Teflon sheet on one side of the polyimide sheet, that is, the disk side, the strength of the pressure receiving member 35 is prevented from deteriorating due to moisture or steam, thereby significantly extending the service life and improving the durability. It can be done.
[0025]
As shown in FIG. 3, the upper inner peripheral surface of the circuit component member 32 that contacts the pressure receiving member 35 and the upper outer peripheral surface of the plunger 23 are in contact with the pressure receiving member 35, that is, the peripheral portion of the contact surface (curvature). Radius: m) R has a curved surface of 0.3 to 2.0, preferably 0.5. By making the curved surface of this curvature, the pressure receiving member 35 is easily elastically deformed by bending in the vertical direction in FIGS. 1 and 2 due to the drive of the electromagnetic drive unit 2 and the vertical movement of the plunger 23 by the spring 27. Further, it is possible to prevent the pressure receiving member 35 from being damaged during elastic deformation.
[0026]
Further, in the state of FIG. 1 in which the solenoid 22 is not energized, and the state of FIG. 2 in which the solenoid 22 is energized to drive the plunger 23 downward, the bending portion gap s in the central portion of the pressure receiving member 35, It is desirable that s shown in FIG. 3 be restricted to 0.8 to 4.0 mm, preferably 1 to 1.2 mm, thereby preventing damage during elastic deformation of the pressure receiving member 35 as described above. it can.
[0027]
In the control valve for a variable capacity compressor having the above-described configuration, the tilting plate 42 in the compressor has a large inclination angle, and the valve portion 17 is closed in a state where the discharge amount of the compressor is large. The pressure is almost equal to the pressure in 46.
[0028]
On the other hand, in order to reduce the discharge amount of the compressor, the energization of the energized solenoid 22 is interrupted. The plunger 23 that has lost the electromagnetic force moves upward due to the elastic force of the spring 27, and opens the state shown in FIG.
[0029]
When the plunger 23 moves upward, the actuating bar 13 pushes up the valve portion 17 against the elastic force of the spring 16 through the pressure receiving member 35 and the disk 14 to open the valve port 18. Then, the opening of the valve port 18 increases the pressure in the crank chamber 41 through the first communication path 6 and the second communication path 7, and as a result, the tilt angle of the tilt plate 42 becomes smaller. The discharge amount of the compressor can be reduced.
[0030]
【The invention's effect】
As described above, according to the present invention, by using a diaphragm having a two-layer structure of a polyimide sheet and a waterproof material made of Teflon coating or Teflon sheet as the pressure receiving member, the rigidity of the pressure receiving member can be reduced. For this reason, the dispersion | variation in the operation characteristic of an electromagnetic drive part can be made small and stable, and the control valve for variable capacity compressors with the stable characteristic can be provided. Further, by performing waterproofing on at least one surface of the pressure receiving member, it is possible to prevent strength deterioration due to moisture, steam, etc., and to significantly extend the life of the pressure receiving member and improve durability.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a control valve for a variable capacity compressor according to the present invention.
FIG. 2 is a cross-sectional view showing another operating state of the control valve shown in FIG.
FIG. 3 is an enlarged cross-sectional view of a pressure receiving member attached between a control valve unit and an electromagnetic drive unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Control valve part 2 Electromagnetic drive part 13 Actuating rod 17 Valve part 23 Plunger 35 Pressure receiving member 40 Variable capacity compressor 41 Crank chamber 46 Suction chamber 47 Discharge chamber s Deflection part clearance of pressure receiving member

Claims (1)

A valve for controlling the pressure in the crank chamber of the compressor; an operating rod that opens and closes in conjunction with the valve; and a pressure in the suction chamber of the compressor that receives the pressure in the compressor and moves the valve in conjunction with the operating rod. In a control valve having a pressure receiving member to be regulated and an electromagnetic driving part for regulating the opening and closing operation of the valve part in conjunction with the operation rod,
A diaphragm as a pressure receiving member is made of a polyimide sheet having a thickness of about 0.05 mm and a polyidimide sheet on the side in contact with a disk-like disk operated by a plunger driven in the axial direction by operation of the electromagnetic drive unit. A two-layer structure is formed by laminating a waterproof material made of Teflon coating or Teflon sheet on one side,
The peripheral portion of the contact surface between the plunger driven by the electromagnetic drive unit and the pressure receiving member is a curved surface (curvature radius: m) of 0.3 to 2.0, and further by the driving of the plunger The bending portion gap of the pressure receiving member is O.D. A control valve characterized by being 8 to 4.0 mm .

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