JP3741038B2 - 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 displacement compressor used in a vehicle air conditioning system.
[0002]
[Prior art]
Conventionally, for example, Japanese Patent Application Laid-Open No. 2000-18420 discloses a control valve having a sleeve and a valve housing in which a movable iron core (plunger) is movably accommodated. In such a control valve, the sleeve and the valve housing are fixed by brazing. By brazing, the position of the sleeve is fixed, and airtightness is ensured to seal the sleeve and the valve housing. Since the valve housing constitutes a yoke, it is made of an iron-based metal, and the sleeve is made of stainless steel having no magnetism. For this reason, the valve housing, which is an iron-based metal, has been plated for rust prevention.
[0003]
In the control valve described in Japanese Patent Application Laid-Open No. 2000-120912, the sleeve and the valve housing are sealed with an O-ring. The sleeve was fixed in position by sandwiching the collar portion between the components of the valve housing.
[0004]
[Problems to be solved by the invention]
However, the brazing process performed by the former control valve is expensive. Further, since the brazing process is performed at a high temperature, the plating process needs to be performed after the sleeve and the valve housing are brazed. However, since the sleeve is made of a stainless material, it is difficult for the plating to adhere to it. Also, since the inner peripheral surface of the sleeve is a sliding surface of the movable iron core, it is not preferable that the plating peels off and becomes a foreign substance. For this reason, when plating is performed, masking is performed so that the inside of the sleeve is not plated. That is, first, the valve housing and the sleeve are brazed, and then the valve housing is plated with the sleeve masked. Therefore, the number of processing steps has been increased by masking to prevent plating in the sleeve.
[0005]
Moreover, in the latter control valve, since it is not necessary to braze, only the valve housing can be plated. However, when the bottomed cylinder is formed like the sleeve of the former control valve, in the control valve with the inside of the sleeve at the high pressure side, a bending stress acts on the collar due to the load applied in the axial direction of the sleeve by the high pressure gas in the sleeve. There is a risk that the flange portion of the sleeve may be deformed. The conventional control valve has the above disadvantages.
[0006]
It is an object of the present invention to seal the sleeve and the valve housing without brazing, to reduce the number of processing steps and to reduce the manufacturing cost, and to prevent deformation of the sleeve even when the inside of the sleeve is used as a high pressure side. An object of the present invention is to provide a control valve for a variable compressor.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, in the control valve of the variable displacement compressor capable of changing the discharge capacity, a movable iron core for operating a valve body disposed in the valve housing; A sleeve made of a non-magnetic material having a bottomed cylindrical shape that encloses the movable iron core, a coil that is disposed outside the sleeve and applies electromagnetic force to the movable iron core, and a yoke that constitutes the valve housing; A gist is provided with a sealing member for sealing between the cylindrical portion of the sleeve and the yoke, and a fixing member made of resin for fixing the position of the sleeve at the bottom surface thereof.
[0008]
According to this invention, the bottomed cylindrical sleeve is fixed at the bottom by the fixing member made of resin, and the space between the cylindrical portion of the sleeve and the yoke is sealed by the sealing member. Further, a magnetic path is formed by the yoke and the movable iron core so that the movable iron core can move.
[0009]
The invention according to claim 2 is summarized in that, in the invention according to claim 1, the fixing member is made of a mold resin for molding the coil.
According to this invention, the bottom surface of the bottomed cylindrical sleeve is fixed by the mold resin.
[0010]
According to a third aspect of the present invention, in the first or second aspect of the invention, the cylindrical portion of the sleeve has a latching portion having a shape in which an opening is widened so as to be hooked by the seal member. The gist.
[0011]
According to the present invention, it is possible to hook the latching portion having a shape with an enlarged opening at the tip of the cylindrical portion of the sleeve onto the seal member. Thereby, it is possible to prevent the sleeve from falling off from the yoke during assembly.
[0012]
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, a nonmagnetic reinforcing member is insert-molded into the fixing member made of the molding resin, and the fixing member is formed of the sleeve. The gist is to hold the bottom surface via the nonmagnetic reinforcing member.
[0013]
According to the present invention, the sleeve holding portion can be reinforced by fixing the bottom surface of the bottomed cylindrical sleeve through the nonmagnetic reinforcing member rather than directly fixing the bottom surface of the sleeve with the fixing member made of mold resin.
[0014]
According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, a magnetic path forming body constituting the yoke is disposed at a position opposite to the seal member in the axial direction with respect to the coil. The gist is that the magnetic path forming body is arranged in a state where it does not extend to the bottom surface of the sleeve.
[0015]
According to this invention, the magnetic path forming body constituting the yoke does not extend to the bottom surface of the bottomed cylindrical sleeve, and the magnetic path entering from the bottom surface of the bottomed cylindrical sleeve is suppressed to be very small. be able to.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in a control valve of a variable displacement swash plate compressor included in a vehicle air conditioner will be described with reference to FIGS. 1 and 2.
[0017]
(Capacity variable swash plate compressor)
As shown in FIG. 1, a variable displacement swash plate compressor (hereinafter simply referred to as a compressor) includes a cylinder block 1, a front housing 2 joined and fixed to the front end thereof, and a valve forming body at the rear end of the cylinder block 1. 3 and a rear housing 4 fixedly joined to each other.
[0018]
A crank chamber 5 is defined in a region surrounded by the cylinder block 1 and the front housing 2. A drive shaft 6 is rotatably supported in the crank chamber 5. The drive shaft 6 is operatively connected to a vehicle engine E as an external drive source. A lug plate 11 is fixed on the drive shaft 6 in the crank chamber 5 so as to be integrally rotatable.
[0019]
A swash plate 12 is accommodated in the crank chamber 5. The swash plate 12 is supported by the drive shaft 6 so as to be slidable and tiltable. The hinge mechanism 13 is interposed between the lug plate 11 and the swash plate 12. Therefore, the swash plate 12 can rotate synchronously with the lug plate 11 and the drive shaft 6 by the hinge connection with the lug plate 11 via the hinge mechanism 13 and the support of the drive shaft 6. Can be tilted with respect to the drive shaft 6 while being slid in the axial direction.
[0020]
A plurality of cylinder bores 1 a (only one is shown in the drawing) are formed so as to penetrate the drive shaft 6 in the cylinder block 1. The single-headed piston 20 is accommodated in each cylinder bore 1a so as to be able to reciprocate. The front and rear openings of the cylinder bore 1a are closed by the valve forming body 3 and the piston 20, and a compression chamber whose volume changes according to the reciprocating motion of the piston 20 is defined in the cylinder bore 1a. Each piston 20 is anchored to the outer peripheral portion of the swash plate 12 via a shoe 19. Therefore, the rotational motion of the swash plate 12 accompanying the rotation of the drive shaft 6 is converted into the reciprocating linear motion of the piston 20 via the shoe 19.
[0021]
A suction chamber 21 and a discharge chamber 22 are defined between the valve forming body 3 and the rear housing 4, respectively. The refrigerant gas in the suction chamber 21 is sucked into the cylinder bore 1a through the suction port 23 and the suction valve 24 formed in the valve forming body 3 by the movement from the top dead center position to the bottom dead center side of each piston 20. Is done. The refrigerant gas sucked into the cylinder bore 1a is compressed to a predetermined pressure by the movement from the bottom dead center position of the piston 20 to the top dead center side, and passes through the discharge port 25 and the discharge valve 26 formed in the valve forming body 3. Through the discharge chamber 22.
[0022]
(Capacity control configuration)
The crank pressure control mechanism for controlling the pressure (crank pressure Pc) of the crank chamber 5 involved in the control of the inclination angle of the swash plate 12 includes an extraction passage 27 provided in the compressor housing shown in FIG. The air supply passage 28 and the control valve CV are used. The bleed passage 27 connects the crank chamber 5 and the suction chamber 21 which is a suction pressure (Ps) region. The supply passage 28 connects the discharge chamber 22 which is a discharge pressure (Pd) region and the crank chamber 5, and a control valve CV is disposed in the middle thereof.
[0023]
Then, by adjusting the opening degree of the control valve CV, the amount of high-pressure discharge gas introduced into the crank chamber 5 via the air supply passage 28 and the amount of gas discharged from the crank chamber 5 via the bleed passage 27 Is controlled and the crank pressure Pc is determined. As the crank pressure Pc is changed, the difference between the crank pressure Pc through the piston 20 and the internal pressure of the cylinder bore 1a (compression chamber) is changed, and the inclination angle of the swash plate 12 is changed. That is, the discharge capacity is adjusted.
[0024]
(Control valve)
As shown in FIG. 2, the control valve CV includes an inlet valve portion that occupies the upper half portion and a solenoid portion 60 that occupies the lower half portion. The inlet side valve portion adjusts the opening degree (throttle amount) of the air supply passage 28 connecting the discharge chamber 22 and the crank chamber 5. The solenoid unit 60 is a kind of electromagnetic actuator for energizing and controlling the operating rod 40 disposed in the control valve CV based on energization control from the outside. The actuating rod 40 is a rod-shaped member that includes a partition wall portion 41 that is a distal end portion, a connecting portion 42, a valve body portion 43 that is substantially in the center, and a guide rod portion 44 that is a proximal end portion. The valve body portion 43 hits a part of the guide rod portion 44.
[0025]
The valve housing 45 of the control valve CV includes a plug body 45a, an upper half main body 45b that constitutes a main outline of the inlet side valve portion, and a yoke 45c that constitutes a main outline of the solenoid portion 60. Yes. A valve chamber 46 and a communication passage 47 are defined in the upper half body 45b of the valve housing 45, and a pressure sensitive chamber 48 is defined between the upper half body 45b and the plug body 45a press-fitted into the upper half body 45b. ing.
[0026]
An operating rod 40 is disposed in the valve chamber 46 and the communication passage 47 so as to be movable in the axial direction (vertical direction in the drawing). The valve chamber 46 and the communication passage 47 can communicate with each other depending on the arrangement of the operation rod 40. On the other hand, the communication passage 47 and the pressure sensing chamber 48 are blocked by the partition wall 41 of the operating rod 40 fitted in the communication passage 47.
[0027]
The bottom wall of the valve chamber 46 is provided by the upper end surface of the fixed iron core 63 described later. A port 51 extending in the radial direction is provided on the peripheral wall of the valve housing 45 surrounding the valve chamber 46, and this port 51 communicates the valve chamber 46 with the discharge chamber 22 through the upstream portion of the air supply passage 28. A port 52 extending in the radial direction is also provided on the peripheral wall of the valve housing 45 surrounding the communication passage 47, and this port 52 communicates the communication passage 47 with the crank chamber 5 via the downstream portion of the air supply passage 28. Therefore, the port 51, the valve chamber 46, the communication passage 47, and the port 52 constitute a part of the air supply passage 28 that allows the discharge chamber 22 and the crank chamber 5 to communicate with each other as a control valve passage.
[0028]
In the valve chamber 46, a valve body 43 of the operating rod 40 is disposed. A step located at the boundary between the valve chamber 46 and the communication passage 47 forms a valve seat 53, and the communication passage 47 forms a kind of valve hole. When the operating rod 40 moves upward from the position shown in FIG. 2 (the lowest movement position) to the uppermost movement position where the valve body 43 is seated on the valve seat 53, the communication passage 47 is blocked.
[0029]
A pressure sensitive member 54 made of a bellows is accommodated in the pressure sensitive chamber 48. The pressure-sensitive member 54 is made of a metal material such as copper, and its upper end is fixed to a plug body 45a of the valve housing 45 by welding or the like. Accordingly, the pressure-sensitive chamber 48 includes a first pressure chamber 55 that is an inner space of the pressure-sensitive member 54 and a second pressure chamber that is an outer space of the pressure-sensitive member 54 by a pressure-sensitive member 54 having a bottomed cylindrical shape. 56.
[0030]
A rod receiver 54a is recessed in the bottom wall portion of the pressure-sensitive member 54, and the tip of the partition wall 41 of the operating rod 40 is inserted into the rod receiver 54a. The pressure-sensitive member 54 is assembled in a state of being compressed and elastically deformed, and is pressed against the partition wall portion 41 via the rod receiver 54a by an urging force based on the elastic deformation.
[0031]
The first pressure chamber 55 communicates with the discharge chamber 22 serving as the first pressure monitoring point P1 through a P1 port 57 and a first pressure detection passage 37 formed in the plug body 45a. The second pressure chamber 56 is communicated with the second pressure monitoring point P2 through a P2 port 58 formed in the upper half main body 45b of the valve housing 45 and the second pressure detection passage 38. That is, the monitoring pressure PdH at the first pressure monitoring point P1 is led to the first pressure chamber 55, and the monitoring pressure PdL at the second pressure monitoring point P2 is led to the second pressure chamber 56.
[0032]
The solenoid unit 60 includes a bottomed cylindrical sleeve 61. The sleeve 61 is sealed with an O-ring 62 as a seal member with respect to a yoke 45c constituting the valve housing 45 at an opening side front end portion 61b of the cylindrical portion 61a. The sleeve 61 is disposed in a state in which the fixed iron core 63 is inserted from the opening side of the cylindrical portion 61 a to a predetermined depth, and the solenoid chamber 64 is partitioned in the sleeve 61 by the fixed iron core 63. A movable iron core 65 is accommodated in the solenoid chamber 64 so as to be movable in the axial direction. A guide hole 66 extending in the axial direction is formed at the center of the fixed iron core 63, and the guide rod portion 44 of the operating rod 40 is disposed in the guide hole 66 so as to be movable in the axial direction. The proximal end (lower end in the figure) of the guide rod portion 44 is fitted and fixed to the movable iron core 65 in the solenoid chamber 64. Therefore, the movable iron core 65 and the operating rod 40 move up and down all the time.
[0033]
In the solenoid chamber 64, a valve body biasing spring 67 made of a coil spring is accommodated between the fixed iron core 63 and the movable iron core 65. The valve body urging spring 67 acts in a direction to move the movable iron core 65 away from the fixed iron core 63 to urge the operating rod 40 (valve body portion 43) downward in the drawing.
[0034]
Around the sleeve 61, there are provided a coil 68a, a magnetic path forming body 68b which is a magnetic body (iron-based metal), and a mold resin portion 68c. The coil 68a is wound around the fixed iron core 63 and the movable iron core 65 in a range straddling the iron cores 63 and 65. The coil 68 a is disposed in a state of being press-fitted into an annular housing recess defined by the inner peripheral surface of the yoke 45 c and the outer peripheral surface of the sleeve 61.
[0035]
The magnetic path forming body 68b is externally fitted to the sleeve 61 in a state of being arranged on the lower side of the coil 68a in the drawing, and the inner peripheral surface thereof is in contact with the cylindrical portion 61a of the sleeve 61. The magnetic path forming body 68 b does not extend to the bottom surface of the sleeve 61. In the present embodiment, the yoke is constituted by the yoke 45c and the magnetic path forming body 68b. A magnetic path is formed by the magnetic path forming body 68 b, the yoke 45 c, the fixed iron core 63, the movable iron core 65, and the operating rod 44.
[0036]
The mold resin portion 68c fixes the bottom surface of the sleeve 61, and the sleeve 61 is positioned by the mold resin portion 68c. That is, the bottom surface of the sleeve 61 is completely covered with the mold resin portion 68c. A terminal pin 69 is provided at the end of the mold resin portion 68c (lower end in FIG. 2).
[0037]
A drive signal is supplied to the coil 68a from the drive circuit 73 based on a command from the control device 72 according to external information (such as cabin temperature information and set temperature information) from the external information detection means 71, and the coil 68a Then, an electromagnetic attractive force (electromagnetic biasing force) having a magnitude corresponding to the power supply amount is generated between the movable iron core 65 and the fixed iron core 63. The energization control for the coil 68a is performed by adjusting the voltage applied to the coil 68a.
[0038]
The plating process necessary for the rust prevention treatment is performed solely on the yoke 45c, and the assembly is performed after the plating process. In the assembly, the yoke 45c and the opening-side tip portion 61b of the cylindrical portion 61a of the sleeve 61 are first assembled in a state where they are sealed by the O-ring 62. Next, a movable iron core 65, a fixed iron core 63, an operating rod 40, etc., which are assembled in advance, are inserted into the sleeve 61, and the inlet side valve portion is assembled. Then, after assembling the coil 68a, the magnetic path forming body 68b, etc. to the yoke 45c, the end is molded with resin. The cylindrical portion 61a of the sleeve 61 is straight and is not fixed with a flange as in the prior art, and the sleeve 61 is fixed on the bottom surface with a mold resin portion 68c. Therefore, even if the control valve CV is used in such a way that the inside of the sleeve 61 becomes the high pressure side, the sleeve fixed to the opening-side tip portion 61b of the cylindrical portion 61a of the sleeve 61 by the collar portion described in the prior art. The bending stress like is not generated.
[0039]
In the present embodiment, the following effects can be obtained.
(1) The bottomed cylindrical sleeve 61 was fixed on the bottom surface with the mold resin portion 68c, and the sleeve 61 and the yoke 45c were sealed with an O-ring 62. Thereby, the brazing process conventionally performed can be abolished. For this reason, the plating process may be performed only on the yoke 45c. Therefore, the masking process of the sleeve 61 is not necessary, and the reduction of processing man-hours and the reduction of manufacturing costs can be realized. Further, deformation of the sleeve 61 due to a load applied in the axial direction due to the high pressure in the sleeve 61 can be prevented.
[0040]
(2) The magnetic path forming body 68b that forms the magnetic path is disposed in a range not extending to the bottom surface of the bottomed cylindrical sleeve 61. Thereby, the amount of magnetic flux entering from the bottom surface of the sleeve 61 can be suppressed. Therefore, it is not necessary to increase the thickness of the bottom surface of the sleeve 61 or dispose a separate nonmagnetic shield, so that the thickness of the bottom surface of the sleeve 61 can be reduced. Therefore, the sleeve 61 can be manufactured by stamping press forming of a stainless steel plate. In addition, since it is not necessary to form a collar on the sleeve 61, a simple shape that can be easily processed can be employed.
[0041]
In addition, the said embodiment of this invention can also be changed and implemented in another form as follows.
As shown in FIG. 3, in the bottomed cylindrical sleeve 61, a latching portion 61c having a shape in which an opening is widened outward is formed at the tip of the cylindrical portion 61a. With such a configuration, since the latching portion 61c is caught by the O-ring 62, both the iron cores 63, 65 are held in the sleeve 61 while the sleeve 61 is held via the O-ring 62 with respect to the yoke 45c during assembly. And when assembling the operating rod 40 and the like, the sleeve 61 is less likely to fall out of the yoke 45c.
[0042]
As shown in FIG. 4, a reinforcing member 74 made of a nonmagnetic metal such as stainless steel or aluminum is insert-molded in the mold resin portion 68c. Thus, the sleeve 61 is fixed by receiving the bottom surface of the bottomed cylindrical sleeve 61 with the reinforcing member 73. With such a configuration, a change in dimensions due to resin creep that occurs when the sleeve 61 is directly received by the mold resin portion 68c can be reduced, the holding portion of the sleeve 61 can be reinforced, and the sleeve 61 caused by resin creep can be reinforced. Misalignment can be prevented.
[0043]
The magnetic path forming body does not have to have an L-shaped cross section. For example, as shown in FIG. 5, the magnetic path forming body 68d may be formed in a cylindrical shape. Even in such a configuration, the same effect can be obtained because the lower end (lower side in the drawing) of the magnetic path forming body 68d does not extend to the bottom surface of the bottomed cylindrical sleeve 61.
[0044]
In the above embodiment, a bellows is used as the pressure-sensitive member 54, but a diaphragm may be used.
A control valve structure in which a ball is accommodated in the rod receiver 54a of the pressure-sensitive member 54 and the pressure-sensitive member 54 and the partition wall 41 of the operating rod 40 are brought into contact with each other via the ball may be employed.
[0045]
2 is changed, the communication passage 47 is connected to the discharge chamber 22 through the upstream portion of the port 52 and the air supply passage 28, and the valve 51 is connected to the discharge passage 22 through the downstream portion of the air supply passage 28. The chamber 46 may be connected to the crank chamber 5.
[0046]
○ The bottomed cylindrical sleeve is not limited to the one in which the opening side tip of the cylindrical portion extends substantially straight in the axial direction. For example, the distal end portion of the cylindrical portion may have an extending portion (a collar portion) that bends at a substantially right angle. In this case, if the extension portion of the sleeve is not sandwiched between the constituent members of the valve housing, there is no problem because bending stress is not applied to the extension portion of the sleeve.
[0047]
O You may make it materialize in PS control valve (control valve which controls discharge capacity according to suction pressure).
○ It may be embodied in a wobble type variable capacity compressor.
[0048]
The technical idea grasped from the embodiment and another example will be described below.
(1) In any one of claims 2, 3, and 5, the bottom surface of the sleeve is covered with the mold resin portion.
[0049]
(2) In any one of claims 1 to 5 and the technical idea (1), the opening-side tip portion of the cylindrical portion of the sleeve extends substantially straight in the axial direction.
[0050]
(3) In any one of claims 1 to 5 and the technical ideas (1) and (2), the seal member is provided between the sleeve portion of the sleeve and the yoke at the tip portion of the sleeve portion. It is characterized by sealing.
[0051]
(4) In any one of claims 1 to 5 and the technical thoughts (1) to (3), the fixing member receives a force toward the bottom surface in the axial direction of the sleeve, thereby causing the sleeve to move in the axial direction. It is characterized by being fixed in position.
[0052]
(5) In any one of claims 1 to 5 and the technical ideas (1) to (4), the fixing member fixes the position of the sleeve in the axial direction in contact with the bottom surface of the sleeve. It is characterized by that.
[0053]
【The invention's effect】
As described above in detail, in the control valve of the variable displacement compressor of the present invention, the sleeve and the valve housing can be sealed without brazing, the processing man-hours can be reduced, the manufacturing cost can be reduced, and the inside of the sleeve can be reduced. Even when used as a high-pressure side, deformation of the sleeve can be avoided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a variable capacity swash plate compressor.
FIG. 2 is a cross-sectional view of a control valve.
FIG. 3 is an enlarged cross-sectional view of a main part showing another example of a control valve.
4 is an enlarged cross-sectional view of a main part showing another example different from FIG. 3. FIG.
FIG. 5 is an enlarged cross-sectional view of a main part showing another example different from FIG. 4;
[Explanation of symbols]
45 ... valve housing, 45c ... yoke constituting the valve housing, 61 ... bottomed cylindrical sleeve, 61a ... cylindrical portion, 61b ... opening side tip, 61c ... latching portion, 62 ... O-ring as seal member, 63 ... fixed iron core, 65 ... movable iron core, 68a ... coil, 68b ... magnetic path forming body constituting the yoke, 68c ... mold resin part, 74 ... reinforcing member, CV ... control valve.

Claims (5)

In a control valve of a variable displacement compressor capable of changing a discharge capacity, a movable iron core that operates a valve body disposed in a valve housing;
A sleeve made of a bottomed cylindrical non-magnetic material movably enclosing the movable iron core;
A coil that is disposed outside the sleeve and applies electromagnetic force to the movable iron core;
A yoke constituting the valve housing;
A seal member that seals between the cylindrical portion of the sleeve and the yoke;
A control valve for a variable displacement compressor, comprising: a fixing member made of a resin for fixing the position of the sleeve at a bottom surface thereof. The control valve for a variable displacement compressor according to claim 1, wherein the fixing member is made of a mold resin for molding the coil. The control valve for a variable displacement compressor according to claim 1 or 2, wherein a hook portion having a shape in which an opening is widened in a shape to be caught by the seal member is provided at a distal end portion of the sleeve portion of the sleeve. The non-magnetic reinforcing member is insert-molded in the fixing member made of the mold resin, and the fixing member holds the bottom surface of the sleeve via the non-magnetic reinforcing member. A control valve for a variable displacement compressor according to claim 1. A magnetic path forming body constituting the yoke is disposed at a position opposite to the seal member in the axial direction with respect to the coil, and the magnetic path forming body is disposed in a state where it does not extend to the bottom surface of the sleeve. The control valve for a variable displacement compressor according to any one of claims 1 to 4, wherein the control valve is provided.

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