JP2017089832A - solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure, in a solenoid valve formed by press-fitting a valve body in a solenoid, satisfactory actuation of a valve element while allowing reduction of a body in size by a simple technique.SOLUTION: A control valve 1 is formed by assembling a valve body 2 and a solenoid 3 in the axial direction. The solenoid 3 has an annular connection part 100 which can receive the end of the valve body 2. The valve body 2 comprises a cylindrical body 5 coaxially having a valve hole 20 and a guide hole 27, and a valve drive body 29 slidably supported in a guide part 106 which defines the guide hole 27. A press-fit part 104 provided at the end of the body 5 is press-fitted in the annular connection part 100. The body 5 has, at least partially in the axial direction, a portion where the press-fit part 104 and the guide part 106 overlap in the radial direction, and has a groove 102 for forming a radial space between the press-fit part 104 and the guide part 106. The press-fit part 104 has a shape symmetrical with respect to the axis of the body 5.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a solenoid valve, and more particularly to a solenoid valve configured by assembling a valve body and a solenoid by press-fitting.

  A control valve that controls the flow of the working fluid is used in an apparatus that performs control using the working fluid. For example, a variable capacity compressor (also simply referred to as a “compressor”) capable of varying the refrigerant discharge capacity is used in an automotive air conditioner so that a constant cooling capacity is maintained regardless of the engine speed. Generally, a solenoid-driven solenoid valve is used for controlling the capacity of the compressor.

  Such an electromagnetic valve is configured by assembling a valve main body that houses the valve mechanism and a solenoid that drives the valve mechanism in the axial direction. The valve body includes a body having a valve hole along the axis, and a valve body that opens and closes the valve portion in contact with and away from the valve hole. The driving force of the solenoid is transmitted to the valve body via a transmission member supported by the body so as to be slidable in the axial direction.

  By the way, such an electromagnetic valve is configured by assembling the body of the valve body and a solenoid in the axial direction, and simple press-fitting is often employed as an assembling method thereof (for example, see Patent Document 1). That is, by pressing the end of the body into the annular connection provided at the end of the solenoid, both are assembled coaxially.

JP 2015-21605 A

  However, it has been found by the inventors' verification that the following problems occur when such press fitting is employed. That is, with the press-fitting, a minute radial deformation occurs at the end of the body. For this reason, when the press-fitting part in the body (the part that is press-fitted into the annular connection part) and the guide part (the part that guides the sliding of the transmission member) overlap in the radial direction, the inner diameter of the guide part by press-fitting Becomes smaller than the design value, and the slidability of the transmission member decreases. As a result, the operability of the valve body is reduced. In order to avoid this, a design in which the press-fitting portion and the guide portion are displaced in the axial direction (that is, a design in which both do not overlap in the radial direction) is conceivable. In addition, a design in anticipation of changes in the inner diameter of the guide portion is conceivable, but it becomes very complicated when dimensional errors and the like are taken into consideration.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a solenoid valve obtained by press-fitting a valve main body into a solenoid, while enabling a reduction in size of the body by a simple method. It is to ensure good operation.

  One aspect of the present invention is an electromagnetic valve configured by assembling a valve body and a solenoid in the axial direction. The solenoid includes a core fixed to the valve body, a plunger provided coaxially with the core, and an annular connection part provided integrally with the core and capable of receiving the end of the valve body. The valve body is slidably supported by a cylindrical body having a valve hole and a guide hole coaxially, a valve body that opens and closes the valve part by opening and closing the valve hole, and a guide part that defines the guide hole. And a valve driving body capable of transmitting the driving force of the solenoid by the operation of the plunger to the valve body. And the valve main body and the solenoid are assembled | attached by press-fitting the press-fit part provided in the edge part of the body in the annular connection part. The body has at least a portion in the axial direction where the press-fit portion and the guide portion overlap in the radial direction, and has a groove for forming a radial space between the press-fit portion and the guide portion. . The press-fit portion has a symmetrical shape with respect to the axis of the body.

  According to this aspect, since the press-fitting portion and the guide portion have a portion that overlaps in the radial direction, the body and thus the solenoid valve can be made smaller accordingly. On the other hand, since a groove is formed between the press-fit portion and the guide portion, even when the end portion of the body is press-fitted into the annular connection portion, even if the press-fit portion is deformed inward in the radial direction, the space by the groove is The deformation can be absorbed. Further, since the press-fit portion has a symmetrical shape with respect to the axis of the body, when the press-fit portion is deformed in the radial direction, the press-fit portion is deformed substantially uniformly around the axis. As a result, the influence of the deformation of the press-fit portion on the guide portion can be eliminated or at least suppressed. That is, the diameter of the guide portion can be maintained substantially equal to that before press-fitting by a simple method of forming a groove in the body, and the slidability of the valve drive body and the operability of the valve body can be maintained well.

  According to the present invention, in an electromagnetic valve obtained by press-fitting a valve main body into a solenoid, it is possible to ensure a good operation of the valve body while making it possible to reduce the size of the body by a simple method.

It is sectional drawing which shows the structure of the control valve which concerns on embodiment. It is a partial expanded sectional view corresponding to the upper half part of FIG. It is a figure showing operation | movement of a control valve. It is a figure which represents roughly the assembly | attachment process of a valve main body and a solenoid. It is the elements on larger scale showing the principal part of an assembly structure.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for the sake of convenience, the positional relationship between the structures may be expressed as upper and lower with reference to the illustrated state.

Drawing 1 is a sectional view showing the composition of the control valve concerning an embodiment.
The control valve 1 is configured as an electromagnetic valve that controls the discharge capacity of a variable capacity compressor (simply referred to as “compressor”) installed in a refrigeration cycle of an automotive air conditioner. This compressor compresses the refrigerant flowing through the refrigeration cycle and discharges it as a high-temperature and high-pressure gas refrigerant. The gas refrigerant is condensed in a condenser (external heat exchanger) and further adiabatically expanded by an expansion device to become a low temperature / low pressure mist refrigerant. The low-temperature and low-pressure refrigerant evaporates in the evaporator, and the passenger compartment air is cooled by the latent heat of vaporization. The refrigerant evaporated in the evaporator is returned again to the compressor and circulates in the refrigeration cycle. The compressor has a rotating shaft that is rotationally driven by an automobile engine, and a compression piston is connected to a swing plate attached to the rotating shaft. The refrigerant discharge amount is adjusted by changing the stroke of the piston by changing the angle of the swing plate. The control valve 1 controls the flow rate of the refrigerant introduced from the discharge chamber of the compressor into the control chamber, thereby changing the angle of the swing plate, and hence the discharge capacity of the compressor. In addition, although the control chamber of this embodiment consists of a crank chamber, in the modification, the pressure chamber separately provided in the crank chamber or the crank chamber may be sufficient.

  The control valve 1 is configured as a so-called Ps sensing valve that controls the flow rate of refrigerant introduced from the discharge chamber into the control chamber so as to keep the suction pressure Ps (corresponding to “sensed pressure”) of the compressor at a set pressure. Yes. The control valve 1 is configured by assembling a valve body 2 and a solenoid 3 in the axial direction. The valve body 2 is a main valve that opens and closes a refrigerant passage for introducing a part of the discharged refrigerant into the control chamber when the compressor is in operation, and a so-called bleed valve that releases the refrigerant in the control chamber to the suction chamber when the compressor is started. Including a functioning secondary valve. The solenoid 3 controls the flow rate of the refrigerant introduced into the control chamber by driving the main valve in the opening / closing direction to adjust the opening degree. The valve body 2 includes a stepped cylindrical body 5, a main valve and a sub valve provided inside the body 5, a power element 6 that generates a force that opposes the solenoid force in order to adjust the opening of the main valve, and the like. It has. The power element 6 functions as a “pressure sensitive part”.

  The body 5 is provided with ports 12, 14, and 16 from the upper end side. The port 12 functions as a “suction chamber communication port” and communicates with the suction chamber of the compressor. The port 14 functions as a “control room communication port” and communicates with the control room of the compressor. The port 16 functions as a “discharge chamber communication port” and communicates with the discharge chamber of the compressor. An end member 13 is fixed so as to close the upper end opening of the body 5. The valve body 2 and the solenoid 3 are fixed by press-fitting the lower end portion of the body 5 into the upper end portion of the solenoid 3.

  In the body 5, a main passage that is an internal passage that communicates the port 16 and the port 14, and a sub passage that is an internal passage that communicates the port 14 and the port 12 are formed. A main valve is provided in the main passage, and a sub valve is provided in the sub passage. That is, the control valve 1 has a configuration in which the power element 6, the sub valve, the main valve, and the solenoid 3 are sequentially arranged from one end side. A main valve hole 20 and a main valve seat 22 are provided in the main passage. A sub valve hole 32 and a sub valve seat 34 are provided in the sub passage.

  The port 12 allows the working chamber 23 defined in the upper part of the body 5 to communicate with the suction chamber. The power element 6 is disposed in the working chamber 23. The port 16 introduces a refrigerant having a discharge pressure Pd from the discharge chamber. A main valve chamber 24 is provided between the port 16 and the main valve hole 20, and the main valve is disposed. The port 14 leads out the refrigerant having the control pressure Pc via the main valve during steady operation of the compressor toward the control chamber, while the refrigerant having the control pressure Pc discharged from the control chamber when the compressor is started. Introduce. A sub valve chamber 26 is provided between the port 14 and the main valve hole 20, and a sub valve is disposed. The port 12 introduces the refrigerant having the suction pressure Ps during the steady operation of the compressor, and guides the refrigerant having the suction pressure Ps to the suction chamber via the auxiliary valve when the compressor is started.

  That is, when the main valve is opened, the port 16 functions as an “introduction port” for introducing the refrigerant from the discharge chamber, and the port 14 serves as an “outlet port” for deriving the refrigerant toward the control chamber. Function. On the other hand, when the auxiliary valve is opened, the port 14 functions as an “introduction port” for introducing the refrigerant from the control chamber, and the port 12 serves as an “outlet port” for deriving the refrigerant toward the suction chamber. Function. The port 14 functions as an “introduction / exit port” for introducing or deriving the refrigerant according to the open / close state of the main valve and the subvalve.

  Cylindrical filter members 15 and 17 are attached to the ports 14 and 16, respectively. The filter members 15 and 17 include a mesh for suppressing entry of foreign matter into the body 5. When the main valve is opened, the filter member 17 restricts entry of foreign matter into the port 16, and when the auxiliary valve is opened, the filter member 15 restricts entry of foreign matter into the port 14.

  A main valve hole 20 is provided between the main valve chamber 24 and the sub valve chamber 26, and a main valve seat 22 is formed at the lower end opening end thereof. A guide hole 25 is provided between the port 14 and the working chamber 23. A guide hole 27 is provided in the lower part of the body 5 (on the side opposite to the main valve hole 20 of the main valve chamber 24). A stepped cylindrical valve driver 29 is slidably inserted into the guide hole 27 (a guide portion 106 described later that defines the guide hole 27).

  The upper half part of the valve drive body 29 is reduced in diameter to form a partition part 33 that partitions the inside and the outside while penetrating the main valve hole 20. A step portion formed at an intermediate portion of the valve driver 29 is a main valve body 30 that is attached to and detached from the main valve seat 22 to open and close the main valve. The main valve body 30 is attached to and detached from the main valve seat 22 from the main valve chamber 24 side, thereby opening and closing the main valve and adjusting the flow rate of refrigerant flowing from the discharge chamber to the control chamber. The upper portion of the partition portion 33 is increased in a tapered shape toward the upper side, and a sub-valve seat 34 is formed at the upper end opening. The auxiliary valve seat 34 functions as a movable valve seat that is displaced together with the valve driver 29. In the present embodiment, the valve driver 29 and the main valve element 30 are distinguished from each other, but the valve driver 29 may be regarded as a “main valve element”.

  On the other hand, a cylindrical sub-valve element 36 is slidably inserted into the guide hole 25. An internal passage of the auxiliary valve body 36 is an auxiliary valve hole 32. This internal passage allows the auxiliary valve chamber 26 and the working chamber 23 to communicate with each other by opening the auxiliary valve. The auxiliary valve body 36 and the auxiliary valve seat 34 are disposed to face each other in the axial direction. The auxiliary valve body 36 opens and closes the auxiliary valve by attaching and detaching to the auxiliary valve seat 34 in the auxiliary valve chamber 26.

  Further, an elongated operating rod 38 is provided along the axis of the body 5. The upper end portion of the operating rod 38 passes through the sub valve body 36 and is connected to the power element 6 so as to be operatively connectable. The lower end portion of the operating rod 38 is connected to a plunger 50 (described later) of the solenoid 3. The upper half of the actuating rod 38 passes through the valve driver 29 and the upper part thereof is reduced in diameter. The subvalve body 36 is extrapolated to the reduced diameter portion and fixed by press-fitting. The tip of the reduced diameter portion is connected to the power element 6.

  A ring-shaped spring receiver 40 is fitted and supported at an intermediate portion in the axial direction of the operating rod 38. A spring 42 (functioning as an “urging member”) that biases the valve driving body 29 in the valve closing direction of the main valve and the subvalve is interposed between the valve driving body 29 and the spring receiver 40. . When the main valve is controlled, the valve drive body 29 and the spring receiver 40 are stretched by the elastic force of the spring 42, and the main valve body 30 and the operating rod 38 operate integrally.

  The power element 6 includes a bellows 45 that is displaced by sensing the suction pressure Ps, and generates a force that opposes the solenoid force by the displacement of the bellows 45. This counter force is also transmitted to the main valve body 30 via the actuating rod 38 and the auxiliary valve body 36. When the auxiliary valve body 36 is seated on the auxiliary valve seat 34 and closes the auxiliary valve, the relief of the refrigerant from the control chamber to the suction chamber is blocked. Further, when the auxiliary valve body 36 is separated from the auxiliary valve seat 34 and opens the auxiliary valve, the refrigerant is allowed to be relieved from the control chamber to the suction chamber.

  On the other hand, the solenoid 3 includes a stepped cylindrical core 46, a bottomed cylindrical sleeve 48 assembled so as to seal the lower end opening of the core 46, and the sleeve 46 accommodated in the axial direction of the core 46. A stepped cylindrical plunger 50 disposed opposite to the core 46, a cylindrical bobbin 52 extrapolated to the core 46 and the sleeve 48, an electromagnetic coil 54 wound around the bobbin 52 and generating a magnetic circuit by energization, A cylindrical case 56 provided to cover the electromagnetic coil 54 from the outside, an end member 58 provided to seal the lower end opening of the case 56, and embedded in the end member 58 below the bobbin 52. A collar 60 made of a magnetic material is provided. The core 46, the case 56, and the collar 60 constitute a yoke. The body 5, the end member 13, the core 46, the case 56, and the end member 58 form the body of the entire control valve 1.

  The valve body 2 and the solenoid 3 are fixed by press-fitting the lower end of the body 5 into the upper end opening of the core 46. A working chamber 28 is formed between the core 46 and the valve driver 29. On the other hand, the operating rod 38 is inserted so as to penetrate the center of the core 46 in the axial direction. The working chamber 28 communicates with the working chamber 23 through the internal passages of the valve drive body 29 and the sub-valve body 36. For this reason, the suction pressure Ps of the working chamber 23 is introduced into the working chamber 28. The suction pressure Ps is also guided to the inside of the sleeve 48 through the communication passage 62 formed by the gap between the operating rod 38 and the core 46.

  Between the core 46 and the plunger 50, a spring 44 (functioning as a “biasing member”) that biases them in a direction to separate them from each other is interposed. The spring 44 functions as a so-called off spring that opens the main valve when the solenoid 3 is off. The operating rod 38 is coaxially connected to each of the auxiliary valve body 36 and the plunger 50. The upper part of the operating rod 38 is press-fitted into the sub-valve body 36, and the lower end part is press-fitted into the upper part of the plunger 50. The actuating rod 38, the auxiliary valve body 36, and the plunger 50 constitute a “movable member” that is integrally displaced with the valve drive body 29 when the main valve is controlled.

  The operating rod 38 appropriately transmits a solenoid force, which is a suction force between the core 46 and the plunger 50, to the main valve body 30 and the sub valve body 36. On the other hand, the actuating rod 38 is loaded with a driving force (also referred to as “pressure-sensitive driving force”) due to the expansion / contraction operation of the power element 6 so as to oppose the solenoid force. That is, in the control state of the main valve, the force adjusted by the solenoid force and the pressure-sensitive driving force acts on the main valve body 30 to appropriately control the opening degree of the main valve. When the compressor is started, the operating rod 38 is displaced relative to the body 5 against the biasing force of the spring 44 in accordance with the magnitude of the solenoid force, and after closing the main valve, the sub valve body 36 is pushed up to Open the valve. Even during the control of the main valve, if the suction pressure Ps is considerably increased, the actuating rod 38 is displaced relative to the body 5 against the urging force of the bellows 45, and the sub valve is closed after the main valve is closed. The body 36 is pushed up to open the auxiliary valve. As a result, the bleed function is exhibited.

  The sleeve 48 is made of a nonmagnetic material. A side surface of the plunger 50 is provided with a communication groove 66 parallel to the axis, and a lower portion of the plunger 50 is provided with a communication hole 68 for communication between the inside and the outside. With such a configuration, the suction pressure Ps is guided to the back pressure chamber 70 through the gap between the plunger 50 and the sleeve 48 even when the plunger 50 is located at the bottom dead center as shown in the figure.

  A pair of connection terminals 72 connected to the electromagnetic coil 54 extend from the bobbin 52, and extend through the end members 58 to the outside. For convenience of explanation, only one of the pair is displayed in the figure. The end member 58 is attached so as to seal the entire structure in the solenoid 3 included in the case 56 from below. The end member 58 is formed by molding (injection molding) of a resin material having corrosion resistance, and the resin material is also filled in the gap between the case 56 and the electromagnetic coil 54. In this way, the resin material fills the gap between the case 56 and the electromagnetic coil 54 so that the heat generated in the electromagnetic coil 54 can be easily transferred to the case 56 and the heat dissipation performance is enhanced. The end portion of the connection terminal 72 is drawn out from the end member 58 and connected to an external power source (not shown).

FIG. 2 is a partially enlarged cross-sectional view corresponding to the upper half of FIG.
A labyrinth seal 74 composed of a plurality of annular grooves for suppressing the circulation of the refrigerant is provided on the sliding surface of the valve driver 29 with the guide hole 27. The spring receiver 40 is formed of a so-called E-ring, is supported so as to be fitted in an annular groove formed in an intermediate portion of the operation rod 38, and is disposed in the operation chamber 28.

  The lower half of the valve driver 29 has an enlarged inner diameter, and the spring 42 is disposed so as to be accommodated in the enlarged diameter portion. With such a configuration, the contact point between the spring 42 and the valve drive body 29 is located closer to the main valve chamber 24 than the center of the sliding portion in the guide hole 27, so that the valve drive body 29 is so-called stubborn. In this manner, the spring 42 is stably supported. As a result, it is possible to prevent or suppress the occurrence of hysteresis due to wobbling when the main valve body 30 is driven to open and close.

  The sub-valve element 36 has an insertion hole 43 that passes through the center in the axial direction. The upper part of the operating rod 38 extends through the insertion hole 43 to the power element 6. The sub-valve body 36 is positioned with respect to the operating rod 38 by being locked to a stepped portion 79 that is the base end of the reduced diameter portion of the operating rod 38. A plurality of internal passages 39 for communicating the internal passage 37 of the valve driver 29 and the working chamber 23 are formed around the insertion hole 43 in the sub valve body 36. The internal passage 39 extends in parallel with the insertion hole 43 and penetrates the auxiliary valve body 36. A labyrinth seal 75 is provided on a sliding surface of the auxiliary valve body 36 with the guide hole 25. In the illustrated state in which the sub-valve body 36 is seated on the sub-valve seat 34, the actuating rod 38 is arranged such that the upper surface of the spring receiver 40 is separated from the lower surface of the valve driver 29 by at least a predetermined interval L. The position of the stepped portion 79 is set. The predetermined interval L functions as so-called “play”.

  When the solenoid force is increased, the operation rod 38 can be displaced relative to the main valve body 30 (valve drive body 29) to push up the sub valve body 36. Thereby, the auxiliary valve body 36 and the auxiliary valve seat 34 can be separated and the auxiliary valve can be opened. Further, the solenoid force can be directly transmitted to the main valve body 30 in a state where the spring receiver 40 and the valve drive body 29 are engaged (contacted), and the main valve body 30 is closed in the valve closing direction. Can be pressed with great force. This configuration functions as an unlocking mechanism for releasing the operation of the main valve element 30 when the operation of the main valve element 30 is locked due to the foreign matter biting into the sliding portion between the valve driver 29 and the guide hole 27.

  The main valve chamber 24 is provided coaxially with the body 5 and is configured as a pressure chamber having a larger diameter than the main valve hole 20. For this reason, a relatively large space is formed between the main valve and the port 16, and a sufficient flow rate of the refrigerant flowing through the main passage can be ensured when the main valve is opened. Similarly, the auxiliary valve chamber 26 is also provided coaxially with the body 5 and is configured as a pressure chamber having a larger diameter than the main valve hole 20. For this reason, a relatively large space is also formed between the auxiliary valve and the port 14. As shown in the figure, the attachment / detachment portion between the upper end of the valve driver 29 and the lower end of the sub-valve body 36 is set so as to be positioned at the intermediate portion of the sub-valve chamber 26. That is, the movable range of the main valve body 30 is set so that the sub valve seat 34 is always located in the sub valve chamber 26, and the sub valve is opened and closed in the sub valve chamber 26. For this reason, when the sub valve is opened, the flow rate of the refrigerant flowing through the sub passage can be sufficiently secured. That is, the bleed function can be effectively exhibited.

  The power element 6 is configured such that the upper end opening of the bellows 45 is closed by a first stopper 82 and the lower end opening is closed by a second stopper 84. The bellows 45 functions as a “pressure sensitive member”, and the first stopper 82 and the second stopper 84 each function as a “base member”. The first stopper 82 is supported coaxially by the end member 13. The stoppers 82 and 84 are formed into a bottomed cylindrical shape by press-molding a metal material, and have a flange portion 86 extending outward in the radial direction at the opening end portion thereof. The bellows 45 has a bellows-like main body, the upper end opening of the main body is air-tightly welded to the flange portion 86 of the first stopper 82, and the lower end opening of the main body is air-tight to the flange portion 86 of the second stopper 84. It is welded to. The inside of the bellows 45 is a sealed reference pressure chamber S, and a spring 88 that urges the bellows 45 in the extending direction between the first stopper 82 and the second stopper 84 inside the bellows 45. Is intervening. The reference pressure chamber S is in a vacuum state in this embodiment.

  The end member 13 is a fixed end of the power element 6. At the center of the lower surface of the end member 13, a support portion 89 protrudes downward. The support portion 89 is coaxially fitted to the first stopper 82 and supports the first stopper 82 from above. Since the tip of the support portion 89 locks the bottom portion of the first stopper 82, the upward displacement of the power element 6 is restricted. By adjusting the amount of press-fitting into the body 5, the set load of the power element 6 (set load of the spring 88) can be adjusted.

  The central portion of the first stopper 82 extends downward toward the inside of the bellows 45, the central portion of the second stopper 84 extends upward toward the inside of the bellows 45, and these are the shafts of the bellows 45. A core is formed. The upper end portion of the operating rod 38 is fitted in the second stopper 84. The bellows 45 expands or contracts in the axial direction (the opening and closing directions of the main valve and the subvalve) according to the differential pressure between the suction pressure Ps of the working chamber 23 and the reference pressure of the reference pressure chamber S. A driving force in the valve opening direction is applied to the main valve body 30 in accordance with the displacement of the bellows 45. Even if the differential pressure increases, if the bellows 45 contracts by a predetermined amount, the second stopper 84 comes into contact with the first stopper 82 and is locked, so that the contraction is restricted.

  In the present embodiment, the effective pressure receiving diameter A of the bellows 45, the effective pressure receiving diameter B (seal part diameter) of the main valve body 30 and the sliding part diameter C (seal part diameter) of the valve drive body 29 The sliding part diameter D (seal part diameter) of the auxiliary valve body 36 is set equal. The term “equal” as used herein may include concepts that are substantially equal (substantially equal) as well as concepts that are completely equal. Therefore, in a state where the valve drive body 29 and the power element 6 are operatively connected, the influence of the discharge pressure Pd, the control pressure Pc, and the suction pressure Ps acting on the combined body of the main valve body 30 and the sub-valve body 36 is affected. Canceled. As a result, in the main valve control state, the main valve body 30 opens and closes based on the suction pressure Ps received by the power element 6 in the working chamber 23. That is, the control valve 1 functions as a so-called Ps sensing valve.

  In this embodiment, in this way, the diameters B, C, and D are made equal, and the internal passage of the valve body (the main valve body 30 and the sub-valve body 36) is vertically penetrated, thereby acting on the valve body ( The influence of Pd, Pc, Ps) can be canceled. That is, the pressure before and after (up and down in the drawing) of the combined body of the auxiliary valve body 36, the valve driving body 29, the operating rod 38 and the plunger 50 can be made the same pressure (suction pressure Ps), thereby realizing the pressure cancellation. Is done. Thereby, the diameter of each valve body can also be set, without depending on the diameter of the bellows 45, and a design freedom is high. For this reason, in a modification, while making diameter B, C, and D equal, effective pressure receiving diameter A may differ from these. That is, the effective pressure receiving diameter A of the bellows 45 may be smaller than the diameters B, C, and D, or larger than the diameters B, C, and D.

  On the other hand, in the present embodiment, the seal portion diameter E in the sub valve of the sub valve body 36 is made smaller than the seal portion diameter effective pressure receiving diameter B in the main valve of the main valve body 30, and the control pressure Pc and the suction pressure Ps are reduced. The differential pressure (Pc−Ps) acts on the valve driver 29 in the valve opening direction of the auxiliary valve. Such a pressure receiving structure and an urging structure by the spring 42 realize a “differential pressure valve opening mechanism” that opens the auxiliary valve when the differential pressure (Pc−Ps) exceeds the set differential pressure ΔPset. Yes.

  On the outer peripheral surface of the body 5, an O-ring 92 is fitted between the port 12 and the port 14, and an O-ring 94 is fitted between the port 14 and the port 16. Further, an O-ring 96 is fitted on the outer peripheral surface near the upper end of the core 46. These O-rings 92, 94, and 96 have a sealing function, and restrict leakage of the refrigerant when the control valve 1 is attached to the attachment hole of the compressor.

Next, the operation of the control valve will be described.
In the present embodiment, a PWM (Pulse Width Modulation) system is adopted for energization control to the solenoid 3. This PWM control is performed by supplying a pulse current of about 400 Hz set to a predetermined duty ratio, and is executed by a control unit (not shown). The control unit includes a PWM output unit that outputs a pulse signal having a designated duty ratio. However, since the configuration itself is employed, detailed description thereof is omitted.

  FIG. 3 is a diagram illustrating the operation of the control valve. FIG. 2 which has already been described shows the minimum capacity operation state of the control valve. FIG. 3 shows a state when the bleed function is operated when the control valve is started. The following description is based on FIG. 1 and with reference to FIGS. 2 and 3 as appropriate.

  When the solenoid 3 is not energized (off) in the control valve 1, that is, when the automobile air conditioner is not operating, no suction force acts between the core 46 and the plunger 50. On the other hand, the urging force of the spring 44 is transmitted to the valve driving body 29 via the plunger 50, the operating rod 38 and the auxiliary valve body 36. As a result, as shown in FIG. 2, the main valve body 30 is separated from the main valve seat 22 and the main valve is fully opened. At this time, the auxiliary valve maintains the closed state.

  On the other hand, when an activation current is supplied to the electromagnetic coil 54 of the solenoid 3 at the time of activation of the automotive air conditioner, as shown in FIG. 3, the valve opening pressure (“sub-valve opening” is determined by the supply current value. If it is higher than "pressure", the secondary valve opens. That is, the solenoid force overcomes the urging force of the spring 42, and the auxiliary valve body 36 is pushed up integrally. As a result, the auxiliary valve body 36 is separated from the auxiliary valve seat 34, the auxiliary valve is opened, and the bleed function is effectively exhibited. During this operation, the main valve body 30 is pushed up by the urging force of the spring 42 and is seated on the main valve seat 22. As a result, the main valve is closed. That is, after the main valve is closed and the introduction of the refrigerant discharged into the control chamber is restricted, the sub valve is opened to quickly relieve the refrigerant in the control chamber to the suction chamber. As a result, the compressor can be started quickly. Note that the “sub-valve opening pressure” changes accordingly when a set pressure Pset, which will be described later, is changed according to the environment in which the vehicle is placed.

  When the current value supplied to the solenoid 3 is within the control current value range of the main valve, the opening of the main valve is adjusted autonomously so that the suction pressure Ps becomes the set pressure Pset set by the supply current value. In the control state of the main valve, the sub valve body 36 is seated on the sub valve seat 34, and the sub valve maintains the closed state. On the other hand, since the suction pressure Ps is relatively low, the bellows 45 extends, and the main valve body 30 operates to adjust the opening of the main valve. At this time, the main valve body 30 is in a valve lift position in which the force in the valve opening direction by the spring 44, the solenoid force in the valve closing direction, and the force in the valve opening direction by the power element 6 according to the suction pressure Ps are balanced. Stop.

  For example, when the refrigeration load increases and the suction pressure Ps becomes higher than the set pressure Pset, the bellows 45 is reduced, so that the main valve body 30 is displaced relatively upward (in the valve closing direction). As a result, the valve opening of the main valve decreases, and the compressor operates to increase the discharge capacity. As a result, the suction pressure Ps changes in a decreasing direction. Conversely, when the refrigeration load is reduced and the suction pressure Ps is lower than the set pressure Pset, the bellows 45 extends. As a result, the power element 6 urges the main valve body 30 in the valve opening direction to increase the valve opening of the main valve, and the compressor operates to reduce the discharge capacity. As a result, the suction pressure Ps is maintained at the set pressure Pset.

  When such steady control is being performed, the load on the engine increases, and when it is desired to reduce the load on the air conditioner, the solenoid 3 in the control valve 1 is switched from on to off. As a result, no suction force acts between the core 46 and the plunger 50, so that the main valve body 30 is separated from the main valve seat 22 by the biasing force of the spring 44, and the main valve is fully opened. At this time, the auxiliary valve body 36 is basically seated on the auxiliary valve seat 34, so that the auxiliary valve is closed. As a result, the refrigerant having the discharge pressure Pd introduced from the discharge chamber of the compressor into the port 16 passes through the fully opened main valve and flows from the port 14 to the control chamber. Therefore, the control pressure Pc is increased and the compressor is operated at the minimum capacity.

Next, the main part of the assembly structure and method of the control valve 1 will be described in detail.
FIG. 4 is a diagram schematically illustrating an assembly process of the valve body and the solenoid. FIG. 5 is a partially enlarged view showing the main part of the assembly structure. FIG. 5A shows the assembly structure of this embodiment, and corresponds to an enlarged view of part A in FIG. FIG. 5B is a partially enlarged view of the assembly structure according to the comparative example. 5 shows a structural portion on one side with respect to the axis of the control valve 1 for the sake of convenience, a similar configuration appears symmetrically with respect to the axis as shown in FIG.

  As shown in FIG. 4, in the assembly process of the control valve 1, the valve body 2 and the solenoid 3 are individually assembled and then assembled together in the axial direction. Schematically, the power member 6, the auxiliary valve body 36, the valve drive body 29, the O-rings 92, 94 and the like are assembled to the body 5 with respect to the filter member 17 below (with the solenoid 3 of the body 5). The filter member 15 is assembled from above (the front end side of the body 5). A partition wall 90 protrudes from the outer peripheral surface of the body 5 so as to separate the port 14 and the port 16, and the filter member 15 and the filter member 17 are engaged with the partition wall 90 so as to be engaged with the body 5. Assembled into. Thus, the control valve 1 is obtained by press-fitting the lower end portion (lower end portion of the body 5) of the valve body 2 to which each filter member is assembled into the upper end opening portion of the core 46. The upper end opening of the core 46 is an annular connection 100 that can receive the lower end 98 of the body 5.

  Thus, since press-fitting is employed for assembling the valve body 2 and the solenoid 3, a predetermined press-fitting allowance is provided between the lower end portion 98 of the body 5 and the annular connection portion 100. In other words, the outer diameter of the body 5 is slightly larger than the inner diameter of the annular connection portion 100 at the press-fitting portion of both. For this reason, in the press-fitting process, the lower end portion 98 of the body 5 receives a radially inward compressive stress. If the inner diameter of the guide hole 27 changes due to this compressive stress, the smooth slidability of the valve drive body 29 may be reduced, and the stable operation of the main valve body 30 may be affected.

  Therefore, in the present embodiment, a concentric annular groove 102 is provided at the lower end portion of the body 5, and a press-fit portion 104 that is press-fitted into the annular connection portion 100 and a guide portion 106 that slidably supports the valve driver 29 are provided. Separated in the radial direction. Although not shown, the annular groove 102 has a shape in which the concave grooves are connected in an annular shape on the lower surface of the body 5. Regarding the thickness in the radial direction at the lower end of the body 5, the thickness on the press-fit portion 104 side is smaller than the thickness on the guide portion 106 side with the annular groove 102 as a boundary. Further, the port 16 is provided at a position avoiding the press-fit portion 104, and the press-fit portion 104 has a symmetrical shape with respect to the axis of the body 5. In the present embodiment, no hole or groove is formed along the peripheral surface of the press-fit portion 104. For this reason, when the press-fit portion 104 is deformed in the radial direction, the press-fit portion 104 is deformed substantially uniformly around the axis. Thereby, the influence of the press-fitting of the press-fitting part 104 does not easily reach the guide part 106, and the inner diameter change of the guide hole 27 at the time of assembly is substantially prevented. In addition, even if the guide hole 27 is accompanied by a slight change in the inner diameter, the guide hole 27 is almost uniformly deformed, so that it is possible to prevent one-sided contact between the guide portion 106 and the valve driver 29, and Smooth slidability can be maintained.

  More specifically, as shown in FIG. 5A, the annular connecting portion 100 has a circular concave hole for inserting the lower end portion of the body 5, and is press-fitted into the lower half portion of the inner peripheral surface thereof. Accept part 104. Further, the inner diameter of the upper half of the annular connecting portion 100 is slightly expanded to be the insertion guide portion 108, while the outer diameter in the vicinity of the lower end of the body 5 is slightly reduced to be the insertion distal end portion 110. Accordingly, the lower end portion of the body 5 can be easily inserted into the annular connection portion 100, and thus the press-fit portion 104 can be easily press-fitted.

  On the other hand, the guide portion 106 is located further in the axial direction of the body 5 than the press-fit portion 104, and ensures the size of the working chamber 28 in combination with the formation of the annular groove 102. The inner peripheral portion of the lower end of the guide portion 106 has a tapered shape that expands downward, facilitating insertion of the valve driver 29 into the body 5.

  In the present embodiment, as illustrated, the length L1 of the press-fit portion 104 and the length L2 of the guide portion 106 are sufficiently large with respect to the dimension in the axial direction. Thereby, the body 5 is firmly fixed to the solenoid 3 and the valve driver 29 is stably supported. In the present embodiment, the length G2 of the insertion guide portion 108 is considerably larger than the length G1 of the insertion tip portion 110. This is to secure a region in which the O-ring 96 is fitted on the outer side in the radial direction of the insertion guide portion 108 in the annular connection portion 100. When the O-ring 96 is not positioned on the annular connecting portion 100, the length of the insertion guide portion 108 can be made smaller than that shown in the drawing.

  In addition, by configuring the press-fit portion 104 and the guide portion 106 so as to have a portion overlapping in the radial direction (overlap portion where the projections in the radial direction overlap each other) in the axial direction by the length h, A compact design in the axial direction of 5 is realized. On the other hand, an annular groove 102 is formed between the press-fit portion 104 and the guide portion 106. The depth D1 of the annular groove 102 with respect to the lower end of the body 5 is set to be sufficiently large, and the bottom portion of the annular groove 102 is located deeper in the axial direction of the body 5 than the overlap portion. That is, the depth of the annular groove 102 is set so that the bottom of the annular groove 102 is farther from the opening end than the press-fit portion 104 with respect to the position in the axial direction with respect to the opening end of the body 5 on the solenoid 3 side. ing. With such a configuration, even when the press-fit portion 104 is deformed inward in the radial direction when the body 5 is press-fitted into the annular connection portion 100, the space Sr by the annular groove 102 can absorb the deformation. As a result, the influence of the deformation of the press-fit portion 104 on the guide portion 106 can be substantially eliminated. As illustrated, when the bottom portion of the annular groove 102 is taken as a reference, the height D2 of the guide portion 106 is smaller than the height D1 of the opening end of the body 5. The height D3 of the sliding surface of the guide portion 106 is smaller than the height D2 of the guide portion 106.

  On the other hand, in the comparative example shown in FIG. 5B, although a radial overlap portion is formed between the press-fit portion 104 and the guide portion 106, a space such as a groove is formed between the two. Absent. In such a configuration, when the press fitting portion 104 is deformed inward in the radial direction when the body 105 is press-fitted into the annular connection portion 100, the deformation leads to the deformation of the guide portion 106, and the inner diameter of the guide hole 27 is reduced. . As a result, the sliding resistance applied to the valve drive body 29 becomes larger than the design value, and the slidability of the valve drive body 29 and thus the operability of the main valve body 30 may be reduced. In other words, according to the present embodiment, such a problem can be avoided.

  In addition, although an overlap portion in the radial direction is formed between the press-fit portion 104 and the guide portion 106, the overlap portion is biased to one side (lower side) in the axial direction of the guide portion 106. For this reason, according to the comparative example, the clearance between the valve driver 29 and the guide portion 106 decreases toward one side in the axial direction. Since the differential pressure (Pd−Ps) between the discharge pressure Pd and the suction pressure Ps acts between the port 16 and the working chamber 28, the clearance decreases toward the low pressure side. For this reason, if a minute foreign matter passes through the filter member 17 and enters the main valve chamber 24, the foreign matter is likely to stay in a place where the clearance becomes small. As a result, the slidability of the valve driver 29 may be reduced. In this regard, according to the present embodiment, the clearance between the valve drive body 29 and the guide portion 106 can be kept substantially constant from the high pressure side toward the low pressure side, and thus such a problem can be avoided. it can.

  As described above, in this embodiment, the inner diameter of the guide portion 106 (that is, the diameter of the guide hole 27) can be maintained substantially equal to that before press-fitting by a simple method of forming the annular groove 102 in the body 5. As a result, the slidability of the valve driver 29 and the operability of the main valve body 30 can be stably maintained as designed.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the technical idea of the present invention. Absent.

  In the above embodiment, as shown in FIG. 5A, an example of the positional relationship between the press-fit portion 104 and the guide portion 106 has been shown. In a modified example, the overlapping portion in the radial direction may be enlarged by extending the guide portion 106 downward from the illustrated configuration. Thereby, the position of the guide part 106 can be brought close to the solenoid 3, and the body 5 can be further downsized. Also in that case, the depth of the annular groove 102 shall be sufficiently ensured. That is, a radial space Sr is formed between the press-fit portion 104 and the guide portion 106 at least in the axial direction region corresponding to the overlap portion.

  In the above embodiment, as the shape of the annular groove 102, a shape (tapered shape) in which the outer wall portion is parallel to the outer peripheral surface of the press-fit portion 104 and the inner wall portion is inclined with respect to the guide portion 106 (guide hole 27) is adopted. . In the modification, other shapes may be used. For example, the inner wall portion of the annular groove may be parallel to the guide portion 106. Moreover, it is good also as a shape (taper shape) which inclines the outer wall part of an annular groove with respect to the outer peripheral surface of the press-fit part 104. FIG.

  In the above embodiment, the thickness on the press-fit portion 104 side is made smaller than the thickness on the guide portion 106 side with the annular groove 102 as a boundary. In the modification, the thicknesses of both may be the same. Alternatively, the thickness on the press-fit portion 104 side may be larger than the thickness on the guide portion 106 side. However, considering the absorption of the compressive stress by the press-fit portion 104 and the securing of the support rigidity by the guide portion 106, the configuration of the above embodiment is preferable.

  In the said embodiment, the example in which the main valve body 30 and the subvalve seat 34 were provided integrally was shown. In a modification, these may be configured separately from each other. Specifically, a valve seat member may be provided separately from the main valve body 30, and the sub valve seat 34 may be formed on the valve seat member.

  In the said embodiment, the example which fixes the subvalve body 36 with respect to the action | operation rod 38 was shown. In a modification, you may comprise both so that relative displacement is possible. Specifically, a spring (functioning as an “urging member”) that slidably inserts the auxiliary valve body 36 shown in FIG. 2 into the operating rod 38 and urges the auxiliary valve body 36 in the valve closing direction. It may be interposed. For example, a spring may be interposed between the sub valve body 36 and the power element 6. However, the displacement of the auxiliary valve body 36 in the valve closing direction is regulated by the step portion 79 of the operating rod 38.

  In the above embodiment, as shown in FIG. 2, the example in which the spring 42 is interposed between the valve driver 29 and the operating rod 38 has been shown. In a modification, the spring 42 may be interposed between the valve driver 29 and the core 46 (the body of the control valve 1).

  In the said embodiment, the structure by which the annular connection part 100 was integrally molded with the core 46 was illustrated. In a modified example, the annular connecting portion and the core may be formed separately and fixed coaxially. In other words, the valve main body and the solenoid may be fixed via an annular connecting portion, and the annular connecting portion may be substantially regarded as a component of the solenoid.

  In the said embodiment, the example which comprised the valve drive body 29 and the action | operation rod 38 by the separate body so that relative displacement was possible was shown. In a modified example, the valve driving body 29 and the operating rod 38 may be integrally fixed with separate members, or the valve driving body 29 and the operating rod 38 may be integrally formed with the same member. In the latter case, it may be configured as a shaft that does not distinguish between the two, and may function as a “valve driver”.

  Although not described in the above embodiment, the radial thickness of the annular connecting portion is made smaller than the radial thickness of the press-fitting portion of the body to prevent or suppress deformation of the press-fitting portion of the body in the radial direction during press-fitting. You may make it do. That is, the deformation of the press-fit portion may be suppressed by making the annular connection portion easily bent outward in the radial direction.

  In the above embodiment, as the control valve, the power element 6 is disposed in the working chamber 23 where the suction pressure Ps is satisfied, and the so-called Ps detection valve that operates by directly sensing the suction pressure Ps is exemplified. In a modified example, a so-called Pc sensing valve that operates by sensing not the suction pressure Ps but the control pressure Pc as the sensed pressure may be used. Alternatively, a movable member including a valve element may be configured as a differential pressure valve that operates by sensing a differential pressure without providing a power element. For example, a Pd-Ps differential pressure valve that operates so that a differential pressure (Pd-Ps) between the discharge pressure Pd and the suction pressure Ps becomes a set differential pressure. Or it is good also as a Pd-Pc differential pressure valve which operate | moves so that the differential pressure (Pd-Pc) of discharge pressure Pd and control pressure Pc may become a setting differential pressure | voltage.

  In the above-described embodiment, the spring is exemplified as the biasing member (elastic body) with respect to the springs 42, 44 and the like, but it goes without saying that an elastic material such as rubber or resin may be adopted.

  In the above embodiment, the reference pressure chamber S inside the bellows 45 is in a vacuum state, but it may be filled with the atmosphere or a predetermined gas as a reference. Alternatively, any one of the discharge pressure Pd, the control pressure Pc, and the suction pressure Ps may be satisfied. And it is good also as a structure which a power element senses the pressure difference inside and outside a bellows suitably, and act | operates. Moreover, in the said embodiment, although it was set as the structure which cancels the pressure Pd, Pc, Ps which a main valve body receives directly, it is good also as a structure which does not cancel at least any one of these pressures.

  In addition, this invention is not limited to the said embodiment and modification, A component can be deform | transformed and embodied in the range which does not deviate from a summary. Various inventions may be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments and modifications. Moreover, you may delete some components from all the components shown by the said embodiment and modification.

1 control valve, 2 valve body, 3 solenoid, 5 body, 6 power element, 12 ports, 14 ports, 16 ports, 20 main valve holes, 20 valve holes, 22 main valve seats, 23 working chamber, 27 guide holes, 28 Actuating chamber, 29 Valve drive body, 30 Main valve body, 32 Sub valve hole, 34 Sub valve seat, 36 Sub valve body, 38 Actuating rod, 46 Core, 50 Plunger, 100 Annular connection part, 102 Annular groove, 102 Groove, 104 Press-in part, 106 guide part, 108 insertion guide part, 110 insertion tip part, Sr space.

Claims (7)

An electromagnetic valve configured by assembling a valve body and a solenoid in the axial direction,
The solenoid is
A core fixed to the valve body;
A plunger provided coaxially with the core;
An annular connection provided integrally with the core and capable of receiving the end of the valve body;
With
The valve body is
A cylindrical body having a valve hole and a guide hole coaxially;
A valve body that opens and closes the valve portion in contact with and away from the valve hole;
A valve drive body that is slidably supported by a guide portion that defines the guide hole, and that can transmit a driving force of the solenoid to the valve body by the operation of the plunger;
With
By press-fitting a press-fitting portion provided at an end of the body into the annular connection portion, the valve body and the solenoid are assembled,
The body is
A portion where the press-fitting portion and the guide portion overlap in the radial direction at least partially in the axial direction;
A groove for forming a radial space between the press-fitting portion and the guide portion;
The electromagnetic valve, wherein the press-fitting portion has a symmetrical shape with respect to the axis of the body.   2. The solenoid valve according to claim 1, wherein in the body, a thickness on the press-fit portion side is smaller than a thickness on the guide portion side with the groove as a boundary.   Regarding the position in the axial direction with respect to the opening end on the solenoid side of the body, the depth of the groove is set such that the bottom of the groove is farther from the opening end than the press-fitting portion. The electromagnetic valve according to claim 1 or 2, characterized in that:   The pressure on the solenoid side with the guide portion as a boundary with respect to the pressure of the fluid in the body is configured to be smaller than the pressure on the side opposite to the solenoid. A solenoid valve according to any one of the above. The electromagnetic capacity for the variable capacity compressor that changes the discharge capacity of the variable capacity compressor that compresses the refrigerant introduced into the suction chamber and discharges it from the discharge chamber by adjusting the flow rate of the refrigerant introduced from the discharge chamber into the control chamber. Configured as a valve,
The body includes a discharge chamber communication port that communicates with the discharge chamber, a control chamber communication port that communicates with the control chamber, a suction chamber communication port that communicates with the suction chamber, and a working chamber that communicates with the suction chamber communication port And
The valve hole is provided in a fluid passage for communicating the discharge chamber communication port and the control chamber communication port;
The solenoid valve according to claim 4, wherein the guide hole is formed between the discharge chamber communication port and the working chamber. The body having a main passage as the fluid passage, and a sub-passage for communicating the control chamber communication port and the suction chamber communication port;
A main valve seat provided in the main passage;
A main valve body that opens and closes the main valve by attaching to and detaching from the main valve seat;
An auxiliary valve seat provided in the auxiliary passage;
A sub-valve element that opens and closes the sub-valve by attaching to and detaching from the sub-valve seat;
An actuating rod connected coaxially to the plunger and transmitting the driving force of the solenoid to the valve driver;
With
While the main valve body is integrally formed with the valve driving body as the valve body, the operation rod is provided so as to be relatively displaceable,
The actuating rod penetrates the valve driver,
The auxiliary valve body is provided integrally with the operating rod;
The sub valve seat is provided integrally with the valve driver;
The electromagnetic valve according to claim 5, wherein the suction chamber communication port and the working chamber communicate with each other through the valve drive body. A pressure sensing unit that senses a predetermined sensed pressure and generates a driving force in the valve opening direction of the main valve according to the magnitude of the sensed pressure;
The actuating rod is disposed between the pressure sensitive portion and the plunger;
The solenoid valve according to claim 6, wherein the opening degree of the main valve is controlled so that the sensed pressure becomes a set pressure corresponding to a supply current value to the solenoid.

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