JP6064185B2 - Control valve for variable capacity compressor - Google Patents

Description

  The present invention relates to a control valve suitable for controlling the discharge capacity of a variable capacity compressor.

  In general, an air conditioner for an automobile compresses the refrigerant flowing through the refrigeration cycle and discharges it as a high-temperature / high-pressure gas refrigerant, a condenser that condenses the gas refrigerant, and adiabatic expansion of the condensed liquid refrigerant. And an expansion device that converts the refrigerant into a low-temperature and low-pressure refrigerant, an evaporator that exchanges heat with the air in the vehicle interior by evaporating the refrigerant, and the like. The refrigerant evaporated in the evaporator is returned to the compressor and circulates in the refrigeration cycle.

  As this compressor, a variable capacity compressor (also simply referred to as “compressor”) capable of varying the refrigerant discharge capacity is used so that a constant cooling capacity is maintained regardless of the engine speed. In this compressor, a piston for compression is connected to a swing plate attached to a rotary shaft that is driven to rotate by an engine, and the discharge amount of the refrigerant is changed by changing the stroke of the piston by changing the angle of the swing plate. adjust. The angle of the swing plate can be continuously changed by introducing a part of the discharged refrigerant into the sealed crank chamber and changing the balance of pressure applied to both surfaces of the piston. The pressure in the crank chamber (hereinafter referred to as “crank pressure”) Pc is controlled by a variable displacement compressor control valve (also simply referred to as “control valve”) provided between the discharge chamber and the crank chamber of the compressor. The

  As such a control valve, for example, there is a valve that controls the crank pressure Pc by adjusting the amount of refrigerant introduced into the crank chamber in accordance with the suction pressure Ps. This control valve senses and displaces the suction pressure Ps, receives a driving force from the pressure sensing unit, controls a valve that opens and closes a passage from the discharge chamber to the crank chamber, and a driving force by the pressure sensing unit. And a solenoid capable of varying the set value by an external current. Such a control valve opens and closes the valve portion so that the suction pressure Ps is maintained at a set pressure set by an external current. In general, since the suction pressure Ps is proportional to the refrigerant temperature at the evaporator outlet, freezing or the like of the evaporator can be prevented by maintaining the set pressure at a predetermined value or higher. Also, when the engine load of the vehicle is large, the solenoid is turned off to fully open the valve unit, the crank pressure Pc is increased, and the swing plate is made substantially perpendicular to the rotating shaft, thereby minimizing the compressor. It can be operated at capacity.

  In recent years, as such a control valve, a main valve is provided in a main passage that communicates the discharge chamber and the crank chamber, while a sub valve is provided in a sub passage that communicates the crank chamber and the suction chamber. A device driven by a single solenoid has also been proposed (see, for example, Patent Document 1). According to this control valve, the opening degree of the main valve is adjusted with the sub valve closed during the steady operation of the air conditioner. Thereby, the crank pressure Pc can be controlled as described above, and the discharge capacity of the compressor can be controlled. On the other hand, when the air conditioner is started, the sub-valve is opened with the main valve closed, so that the crank pressure Pc is quickly reduced, so that the compressor is shifted to the maximum capacity operation state relatively quickly. Can be demonstrated.

JP 2008-240580 A

  However, in such a control valve, when the suction pressure Ps is low, the urging force of the pressure sensing part acts greatly in the closing direction of the sub valve, so that even if the solenoid is turned on, the sub valve cannot be opened quickly, or There was a problem that the opening degree of the secondary valve could not be obtained sufficiently.

  The present invention has been made in view of such a problem, and in a control valve for a variable capacity compressor provided with a pressure sensitive part, the bleed function is effectively exhibited without depending on the pressure sensed by the pressure sensitive part. For the purpose.

  In order to solve the above-described problem, an aspect of the present invention provides a discharge capacity of a variable capacity compressor that compresses the refrigerant introduced into the suction chamber and discharges the refrigerant from the discharge chamber. It is a control valve that is changed by adjusting the flow rate. The control valve includes a body formed with a main passage for communicating the discharge chamber and the crank chamber, a sub passage for communicating the crank chamber and the suction chamber, a main valve seat provided in the main passage, and a main valve. A main valve body that opens and closes the main valve by attaching to and detaching from the seat; and a pressure-sensitive member that senses a predetermined sensed pressure and is displaced in the opening and closing direction of the main valve, and the main valve body according to the displacement of the pressure-sensitive member Is arranged between the power element and the solenoid, and the power element that can generate a force that opposes the driving force of the power element when energized. The auxiliary rod for transmitting to the auxiliary valve, the auxiliary valve seat provided in the auxiliary passage, and the auxiliary rod of the power element are integrally provided at the opposite end, and the auxiliary valve is attached to and detached from the auxiliary valve seat to open and close the auxiliary valve. Energize the valve body and auxiliary valve body in the valve closing direction Comprising a biasing member. When the control current of the main valve is supplied to the solenoid, the sub-valve element sits on the sub-valve seat and functions as a fixed end of the power element, and the solenoid supplies a current that is greater than the set value greater than the control current. When this is done, the urging force of the urging member is set so that the sub-valve element can be separated from the sub-valve seat and displaced integrally with the power element.

  According to this aspect, since the pressure-sensitive part is configured as a movable power element, the sub-valve element is opened and closed by a balance between the force in the valve opening direction by the solenoid and the force in the valve closing direction by the biasing member. Become. That is, the effect of the sensed pressure is substantially not exerted when the auxiliary valve is opened or closed. As a result, according to the control valve of this aspect, the bleed function can be effectively exhibited without depending on the pressure sensed by the pressure sensing unit as long as the current exceeding the set value is supplied.

  According to the present invention, a bleed function can be effectively exhibited in a control valve for a variable displacement compressor including a pressure sensing unit without depending on the pressure sensed by the pressure sensing unit.

It is sectional drawing which shows the structure of the control valve which concerns on 1st 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 showing operation | movement of a control valve. It is a figure showing operation | movement of a control valve. It is a partial expanded sectional view corresponding to the upper half part of the control valve concerning a 2nd embodiment. It is a partial expanded sectional view corresponding to the upper half part of the control valve concerning a 3rd embodiment.

  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.

[First Embodiment]
FIG. 1 is a cross-sectional view illustrating a configuration of a control valve according to the first embodiment.
The control valve 1 is configured as an electromagnetic valve that controls the discharge capacity of a variable capacity compressor (not shown) (simply referred to as “compressor”) installed in the refrigeration cycle of the 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 crank chamber, thereby changing the angle of the swing plate, and thus the discharge capacity of the compressor.

  The control valve 1 is configured as a so-called Ps sensing valve that controls the flow rate of the refrigerant introduced from the discharge chamber into the crank 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 integrally assembling a valve body 2 and a solenoid 3. 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 crank chamber when the compressor is in operation, and a so-called bleed valve that releases the refrigerant in the crank 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 crank 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, 16, and 18 from its upper end side. Ports 12 and 18 function as "crank chamber communication ports" and communicate with the crank chamber of the compressor. The port 14 functions as a “suction chamber communication port” and communicates with the suction chamber 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 end member 13 is provided with a plurality of communication holes communicating with the inside and outside of the body 5, and these communication holes constitute the port 12. The lower end of the body 5 is connected to the upper end of the solenoid 3.

  In the body 5, a main passage that communicates the port 16 and the port 18 and a sub passage that communicates the port 12 and the port 14 are formed. A main valve is provided in the main passage, and a sub valve is provided in the sub passage. The control valve 1 has a configuration in which a sub valve, a power element 6, a main valve, and a 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 16 introduces a refrigerant having a discharge pressure Pd from the discharge chamber. The port 18 guides the refrigerant that has passed through the main valve toward the crank chamber during steady operation of the compressor. On the other hand, the port 12 introduces a refrigerant having a crank pressure Pc discharged from the crank chamber when the compressor is started. The refrigerant introduced at this time is guided to the auxiliary valve. The port 14 introduces the refrigerant having the suction pressure Ps during the steady operation of the compressor, and guides the refrigerant through the sub valve toward the suction chamber when the compressor is started. An annular strainer 15 is attached to the port 16. The strainer 15 includes a filter for suppressing entry of foreign matter into the body 5.

  A main valve hole 20 is provided between the port 16 and the port 18, and a main valve seat 22 is formed at the lower end opening thereof. A guide hole 25 is provided between the port 16 and the port 14. A guide hole 26 is provided in the lower part of the body 5 (on the side opposite to the main valve hole 20 of the port 18). A cylindrical main valve body 30 is inserted through the lower half of the body 5. The main valve body 30 is supported at two points by the body 5 in such a manner that one end side is slidably supported by the guide hole 25 and the other end side is slidably supported by the guide hole 26. The main valve body 30 is attached to and detached from the main valve seat 22 from the port 18 side to open and close the main valve, and adjust the flow rate of refrigerant flowing from the discharge chamber to the crank chamber.

  On the other hand, a ring-shaped valve seat forming member 31 is press-fitted between the port 12 and the port 14 in the body 5. A sub valve hole 32 is provided inside the valve seat forming member 31, and a sub valve seat 34 is formed at the upper end opening thereof. On the port 12 side of the valve seat forming member 31, a disc-shaped sub-valve element 36 is disposed. The auxiliary valve 36 opens and closes when the auxiliary valve body 36 is attached to and detached from the auxiliary valve seat 34. The auxiliary valve body 36 divides the auxiliary passage into a capacity chamber 37 that communicates with the port 12 and a working chamber 39 that communicates with the port 14. A spring 40 (which functions as a “biasing member”) that biases the sub-valve body 36 in the valve closing direction is interposed between the sub-valve body 36 and the end member 13.

  Further, an elongated operating rod 38 is provided along the axis of the body 5. The upper end portion of the operating rod 38 is connected to the power element 6 via the transmission member 33 so as to be operatively connectable. The lower end portion of the operating rod 38 is connected to a plunger 50, which will be described later, of the solenoid 3 so as to be operable and connectable. The upper half of the operating rod 38 penetrates the main valve body 30 and supports the transmission member 33 from below at its upper end. The transmission member 33 is provided with a communication hole 35 that communicates the inside and the outside. The communication hole 35 allows the internal passage 43 of the main valve body 30 and the working chamber 39 to communicate with each other. Between the main valve body 30 and the solenoid 3, a spring 42 (functioning as "another urging member") for urging the main valve body 30 in the valve closing direction of the main valve is interposed.

  The power element 6 is disposed in the working chamber 39 and is sandwiched between the auxiliary valve body 36 and the transmission member 33. The power element 6 includes a bellows 45 (functioning as a “pressure-sensitive member”) that senses and displaces the suction pressure Ps, and applies a driving force in the valve opening direction to the main valve body 30 according to the displacement of the bellows 45. To do. This driving force is transmitted to the main valve body 30 via the transmission member 33. Between the power element 6 and the transmission member 33, a spring 44 (functioning as an “urging member”) that biases the transmission member 33 toward the main valve body 30 is interposed. In the present embodiment, the load of the spring 44 is set larger than the load of the spring 42, and the load of the spring 40 is set larger than the load of the spring 44. A pressure chamber 24 is formed between the lower end portion of the body 5 and the solenoid 3. The suction pressure Ps of the working chamber 39 is introduced into the pressure chamber 24 through the communication hole 35 and the internal passage 43.

  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 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, and an electromagnetic coil A cylindrical case 56 is provided so as to cover 54 from the outside and also functions as a yoke, and an end member 58 provided to seal the lower end opening of the case 56. In the present embodiment, the body 5, 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 pressure chamber 24 is formed between the core 46 and the main valve body 30. A ring-shaped shaft support member 60 is press-fitted into the upper end portion of the core 46, and the operating rod 38 is supported by the shaft support member 60 so as to be slidable in the axial direction. A communication groove parallel to the axis is formed at a predetermined location on the outer peripheral surface of the shaft support member 60. The suction pressure Ps of the pressure chamber 24 is also guided to the inside of the sleeve 48 through the communication groove, the communication path 62 formed by the gap between the operating rod 38 and the core 46.

  The communication path 62 functions as an orifice for making the inside of the sleeve 48 an oil damper chamber. That is, in the present embodiment, in the manufacturing process of the control valve 1, oil of the same type as that contained in the refrigerant is lubricated in the sleeve 48 in advance for lubricating the compressor. In the present embodiment, the communication groove provided in the shaft support member 60 functions as a throttle passage that resists oil entering and exiting the sleeve 48. With such a configuration, the sleeve 48 can function as an oil damper chamber, and minute vibrations of the plunger 50 disposed in the sleeve 48 are suppressed. As a result, the generation of noise due to such minute vibration is prevented or suppressed. In the modified example, the communication path 62 may function as a throttle path that resists oil entering and exiting the sleeve 48. That is, at least one of the communication groove and the communication path 62 provided in the shaft support member 60 may function as a throttle path.

  The sleeve 48 is made of a nonmagnetic material. Plural communicating grooves 66 parallel to the axis are provided on the side surface of the plunger 50, and plural communicating grooves 68 extending in the radial direction and communicating between the inside and the outside are provided on the lower end surface of the plunger 50. 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).

  The spring 44 also functions as an off-spring that urges the core 46 and the plunger 50 in a direction to separate them from each other. Note that the lower end portion of the operating rod 38 may be press-fitted and fixed to the plunger 50, but may be merely brought into contact therewith. This is because the spring 44 (off spring) is provided between the transmission member 33 and the power element 6, so that there is no problem even if the press-fitting and fixing between the operating rod 38 and the plunger 50 is omitted. Rather, by eliminating such press-fitting and fixing, it is possible to improve the workability of parts of the actuating rod 38 and the plunger 50 and their assemblability.

  The operating rod 38 is supported from below by the plunger 50 and is configured to be operatively connected to the main valve body 30 via the transmission member 33, while being operatively connected to the sub-valve body 36 via the transmission member 33 and the power element 6. It is configured to be possible. 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 via the transmission member 33 to appropriately control the opening degree of the main valve.

  In addition, since the load of the spring 40 is set to be sufficiently large, the sub valve is basically not opened in the control state of the main valve. That is, in a state where the control current of the main valve is supplied to the solenoid 3, the sub valve body 36 is seated on the sub valve seat 34 and functions as a fixed end of the power element 6. For this reason, the bellows 45 can be stably expanded or contracted in the valve opening direction of the main valve according to the magnitude of the suction pressure Ps. As a result, the operation of the main valve body 30 is also stabilized, and the opening of the main valve is adjusted stably.

  On the other hand, when the main valve is closed, the actuating rod 38 is displaced relative to the main valve body 30 in accordance with the magnitude of the solenoid force, and the sub valve can be opened. That is, when a current (starting current) greater than a set value larger than the control current of the main valve is supplied to the solenoid 3, the solenoid force overcomes the load of the spring 40, and the power element 6 and the sub valve body 36 are integrated. Push up. As a result, the auxiliary valve body 36 is separated from the auxiliary valve seat 34 and the auxiliary valve is opened. Thereby, the bleed function is exhibited. In other words, the load of the spring 40 is set so that the sub-valve element 36 can be separated from the sub-valve seat 34 and integrally displaced with the power element 6 when a current equal to or greater than the set value is supplied to the solenoid 3. In the present embodiment, the control current of the main valve is set to a range up to 0.68 A, and the set value is set to 0.8 A, but other current value ranges may be set. In the present embodiment, when the control valve 1 is started, a starting current greater than the set value is supplied to the solenoid 3 to open the sub-valve to exert the bleed function. However, other than when the control valve 1 is started (for example, The sub-valve may be opened as required also during the control of the main valve.

FIG. 2 is a partially enlarged cross-sectional view corresponding to the upper half of FIG.
The main valve body 30 is attached to and detached from the main valve seat 22 at a tapered step provided in the middle thereof, and opens and closes the main valve. The inner diameter of the upper end portion of the main valve body 30 is slightly enlarged, and a locking portion 74 capable of locking the transmission member 33 from below is formed. The transmission member 33 has a bottomed cylindrical shape, and a flange portion 76 extending outward in the radial direction is provided at a lower end opening thereof. The transmission member 33 is attached to and detached from the locking portion 74 at the flange portion 76. The communication hole 35 is provided on the side portion of the transmission member 33. The operating rod 38 has a reduced diameter at the top and penetrates the main valve body 30. The upper end portion of the operating rod 38 is accommodated in the transmission member 33, and the distal end surface thereof is connected so as to contact the bottom portion of the transmission member 33.

  The power element 6 includes a base member 84 and a bellows 45. The base member 84 is formed by pressing a metal material into a bottomed cylindrical shape, and has a flange portion 86 extending outward in the radial direction at an upper end opening thereof. The bellows 45 is closed at the lower end of the bellows-shaped main body, and the upper end opening is airtightly welded to the lower surface of the flange portion 86. The inside of the bellows 45 is a sealed reference pressure chamber S, and a spring 88 that biases the bellows 45 in the extending direction is interposed between the bellows 45 and the flange portion 86. The reference pressure chamber S is in a vacuum state in this embodiment. The bellows 45 expands and contracts with the main body of the base member 84 as an axis. The bellows 45 is supported by the transmission member 33 at the end opposite to the flange portion 86. On the other hand, the sub-valve element 36 is provided so as to abut on the upper end surface (side surface opposite to the bellows 45) of the base member 84.

  That is, the power element 6 and the auxiliary valve body 36 are elastically supported between the end member 13 and the transmission member 33. The main body of the base member 84 extends inward of the bellows 45 to the vicinity of the bottom thereof, and the bottom thereof is disposed close to the bottom of the bellows 45. The transmission member 33 has an upper end surface that can contact the lower end surface of the bellows 45. The bellows 45 expands or contracts in the axial direction (opening / closing direction of the main valve) according to the differential pressure between the suction pressure Ps of the working chamber 39 and the reference pressure of the reference pressure chamber S. However, even if the differential pressure increases, if the bellows 45 contracts by a predetermined amount, the main body of the base member 84 comes into contact with and is locked, so that the contraction is restricted.

  An insertion hole 90 is provided at the center of the sub valve body 36. A columnar shaft portion 92 extends downward from the center of the lower surface of the end member 13. The axis of the shaft portion 92 and the axis of the operating rod 38 are configured to coincide with each other. The shaft portion 92 passes through the insertion hole 90 and is partially inserted into the upper portion of the base member 84. With such a configuration, the power element 6 can be displaced in the axial direction while being stably supported so that the base member 84 slides on the shaft portion 92. The load of the spring 40 (the set load for opening the auxiliary valve) can be adjusted by adjusting the press-fitting amount of the end member 13 into the body 5.

  In the present embodiment, the effective pressure receiving diameter A (seal part diameter) of the sliding part with the guide hole 25 of the main valve body 30 and the effective pressure receiving diameter B (seal part diameter) of the main valve of the main valve body 30 are as follows. Are set equal. For this reason, the influence of the discharge pressure Pd acting on the main valve body 30 is cancelled. Further, although the effective pressure receiving diameter C (seal part diameter) of the sliding portion with the guide hole 26 of the main valve body 30 is slightly larger than the effective pressure receiving diameters A and B, they are set to be approximately equal. For this reason, the influence of the crank pressure Pc and the suction pressure Ps that directly act on the main valve body 30 in the control state of the main valve is substantially 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 39. That is, the control valve 1 functions as a so-called Ps sensing valve.

  As described above, the effective pressure receiving diameters A, B, and C are made substantially equal, and the pressure (Pd, Pc, Ps) acting on the main valve body 30 is increased by vertically passing through the internal passage 43 of the main valve body 30. The influence can be canceled. That is, the pressure before and after (up and down in the figure) of the combined body of the transmission member 33, the main valve body 30, the operating rod 38 and the plunger 50 can be made the same pressure (suction pressure Ps), thereby realizing pressure cancellation. The Thereby, the diameter of the main valve body 30 can be set without depending on the diameter of the bellows 45. That is, the effective pressure receiving diameter of the bellows 45 may be equal to the effective pressure receiving diameters A, B, and C, or may be larger or smaller. For this reason, the design freedom of the bellows 45 and the main valve body 30 is high.

  In such a configuration, in a stable control state of the control valve 1, the main valve operates autonomously so that the suction pressure Ps of the working chamber 39 becomes a predetermined set pressure Pset. This set pressure Pset is basically adjusted in advance by the spring load of the springs 42, 44, 88, and is set as a pressure value that can prevent freezing of the evaporator from the relationship between the temperature in the evaporator and the suction pressure Ps. The The set pressure Pset can be changed by changing the supply current (set current) to the solenoid 3.

  On the other hand, when a current equal to or greater than the set value is supplied to the solenoid 3 when the control valve 1 is started, a solenoid force that overcomes the load of the spring 40 is applied to the sub-valve element 36 via the power element 6. As a result, the auxiliary valve body 36 and the auxiliary valve seat 34 can be separated from each other to open the auxiliary valve. That is, the control valve 1 has a “forced valve opening mechanism” for forcibly opening the auxiliary valve using the driving force of the solenoid 3.

Next, the operation of the control valve will be described.
3-5 is a figure showing operation | movement of a control valve, and respond | corresponds to FIG. FIG. 2 which has already been described shows the minimum capacity operation state of the control valve. 3 and 4 show the state when the bleed function is operated when the control valve is activated. FIG. 3 shows a state when the suction pressure Ps is high, and FIG. 4 shows a state when the suction pressure Ps is low. FIG. 5 shows a relatively stable control state. The following description is based on FIG. 1 and with reference to FIGS.

  When the solenoid 3 is not energized in the control valve 1, that is, when the automotive air conditioner is not operating, no suction force acts between the core 46 and the plunger 50. On the other hand, the suction pressure Ps is relatively high under a normal environment. For this reason, as shown in FIG. 2, the urging force of the spring 44 is transmitted to the main valve body 30 via the transmission member 33 in a state where the bellows 45 is contracted. As a result, the main valve body 30 is separated from the main valve seat 22 and the main valve is fully opened. At this time, the power element 6 does not substantially function, and a force in the valve opening direction does not act on the auxiliary valve body 36. For this reason, the auxiliary valve maintains a closed state.

  On the other hand, when a starting current exceeding the set value is supplied to the electromagnetic coil 54 of the solenoid 3 at the time of starting the automobile air conditioner, the solenoid force overcomes the biasing force of the spring 40 as shown in FIG. 6 and the auxiliary valve body 36 are 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. In this operation process, the transmission member 33 is pushed up by the actuating rod 38, so that the main valve body 30 is pushed up by the biasing force of the spring 42 and is seated on the main valve seat 22. As a result, the main valve is closed. That is, when the starting current is supplied to the solenoid 3, the main valve is closed to restrict the introduction of the refrigerant discharged into the crank chamber, and at the same time, the sub valve is immediately opened to quickly relieve the refrigerant in the crank chamber to the suction chamber. As a result, the compressor can be started quickly.

  Further, even when the suction pressure Ps is low and the bellows 45 is extended as shown in FIG. 4 as in the case where the vehicle is placed in a low temperature environment, for example, the starting current exceeding the set value is supplied to the solenoid 3. By doing so, the auxiliary valve can be opened, and the compressor can be started quickly. That is, in the state shown in FIGS. 3 and 4, the sub-valve element 36 does not function as a fixed end of the power element 6 and the power element 6 is suspended, so that the driving force of the power element 6 is changed to the solenoid force. There is virtually no competition. For this reason, in order to open the auxiliary valve, it is sufficient to generate a solenoid force that can overcome the load of the spring 40. That is, it suffices to supply current exceeding the set value to the solenoid 3.

  When the current value supplied to the solenoid 3 is within the control current value range of the main valve, the load of the spring 40 is sufficiently larger than the solenoid force, so that the sub valve body 36 is connected to the sub valve seat as shown in FIG. The sub-valve maintains a 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 opens in the valve opening direction by the power element 6 according to the force in the valve opening direction by the spring 44, the force in the valve closing direction by the spring 42, the solenoid force in the valve closing direction, and the suction pressure Ps. Stops at the valve lift position where the power of the balance is balanced.

  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, since the auxiliary valve body 36 is seated on the auxiliary valve seat 34, 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 14 passes through the fully opened main valve and flows from the port 12 to the crank chamber. Therefore, the crank pressure Pc is increased and the compressor is operated at the minimum capacity.

  As described above, in the present embodiment, the base end portion of the power element 6 is fixed or movable according to the current value supplied to the solenoid 3. That is, the sub-valve element 36 functions as a fixed end of the power element 6 in the control state of the main valve, and the sub-valve element 36 can be displaced integrally with the power element 6 when a current exceeding the set value is supplied to the solenoid 3. The load of the spring 40 was set. As a result, as long as a current equal to or higher than the set value is supplied to the solenoid 3, the auxiliary valve can be opened without depending on the suction pressure Ps sensed by the power element 6, and the bleed function can be effectively exhibited.

[Second Embodiment]
FIG. 6 is a partially enlarged cross-sectional view corresponding to the upper half of the control valve according to the second embodiment. Below, it demonstrates centering on difference with 1st Embodiment. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals.

  The control valve 201 is configured so that the set load of the power element 206 (the set load of the spring 88) can be easily adjusted after the assembly, and the control valve 201 is locked by foreign matter biting into the sliding portion of the main valve body 230. Is different from the first embodiment in that a lock release mechanism is provided for releasing the occurrence of the occurrence of the problem. The control valve 201 is configured by integrally assembling a valve main body 202 and a solenoid 203. In this embodiment as well, the body 205, the core 246, the case 56, and the end member 58 form the body of the entire control valve 201.

  In the present embodiment, the positions of the ports 16 and 18 are upside down with respect to the first embodiment. That is, as a port disposed opposite to the main valve body 230, a port for introducing the discharge pressure Pd is disposed on the side relatively close to the solenoid 203, and a port for deriving the crank pressure Pc on the relatively remote side. Is arranged. The shaft support member 60 as in the first embodiment is not provided at the upper end portion of the core 246.

  The power element 206 is disposed on the body 205 in such a manner that the power element 6 of the first embodiment is turned upside down. A convex portion is provided at the center of the upper surface of the bellows 245. On the other hand, the auxiliary valve body 236 has a stepped disk shape, and an engaging portion 237 complementary to the upper surface of the bellows 245 is provided at the center of the lower surface. The sub-valve element 236 and the bellows 245 are engaged with each other so that the both are positioned. The power element 206 has a base member 84 supported by the transmission member 33 from below. The spring 44 is interposed between the base member 84 and the transmission member 33.

  The auxiliary valve hole 32 and the auxiliary valve seat 34 are formed integrally with the body 205. The auxiliary valve body 236 is attached to and detached from the auxiliary valve seat 34 at the end face of the lower end opening. An end member 213 is fixed to the upper end portion of the body 205. The end member 213 has a ring shape and is fixed by crimping the upper end opening of the body 205. Between the end member 213 and the sub valve body 236, a spring 240 (functioning as a “biasing member”) that biases the sub valve body 236 in the valve closing direction is interposed. The spring 240 has a conical shape, and has a small-diameter end connected to the sub-valve 236 and a large-diameter end connected to the end member 213. This makes it easy to insert a tool for adjusting the set load of the power element 206 from the upper end opening of the body 205. That is, in this embodiment, after the control valve 201 is assembled, the set load of the power element 206 (the set load of the spring 88) can be easily adjusted by deforming the central portion of the upper surface of the sub-valve element 236. ing.

  A partition wall 270 is provided on the upper portion of the main valve body 230. The partition wall 270 functions as an “engaged portion” that can be appropriately engaged and connected to the operation rod 238 on the lower surface thereof. The upper portion of the operating rod 238 has a reduced diameter and passes through an insertion hole provided in the center of the partition wall 270. In the operating rod 238, an engaging portion 272 is constituted by a step of the reduced diameter portion. Around the insertion hole of the partition wall 270, a plurality of through holes 276 for allowing the refrigerant to pass therethrough are formed. Note that the position of the step of the operating rod 238 is set so that the engaging portion 272 is separated from the partition wall 270 with at least a predetermined interval L in a state where the transmission member 33 is seated on the locking portion 74. The predetermined interval L functions as so-called “play”.

  When the solenoid force is increased, the transmission rod 33 can be pushed up by displacing the operating rod 238 relative to the main valve body 230. 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 230 in a state in which the engaging portion 272 and the partition wall 270 are engaged (contacted), and the main valve body 230 has a large force in the valve closing direction of the main valve. Can be pressed. This configuration functions as an unlocking mechanism for releasing the main valve body 230 when the main valve body 230 is locked due to the foreign matter biting into the sliding portions of the main valve body 230 and the guide holes 25 and 26.

  Also in the present embodiment, the sub-valve element 236 functions as a fixed end of the power element 206 in the control state of the main valve, and the sub-valve element 236 is connected to the power element 206 when a current exceeding the set value is supplied to the solenoid 203. The load of the spring 240 is set so that it can be displaced integrally. Thereby, the effect similar to 1st Embodiment can be acquired. Furthermore, the set load of the spring 88 can be finely adjusted by accurately deforming the set pressure Pset by deforming the central portion of the sub-valve element 236 in the axial direction with the assembly of the control valve 201 being almost completed. can do.

[Third Embodiment]
FIG. 7 is a partially enlarged cross-sectional view corresponding to the upper half of the control valve according to the third embodiment. Below, it demonstrates centering on the difference with 1st, 2nd embodiment. In the figure, the same reference numerals are assigned to components that are substantially the same as those in the first and second embodiments.

  The control valve 301 has substantially the same configuration as the control valve 201 of the second embodiment except that the positions of the ports 12 and 14 are different. The control valve 301 is configured by integrally assembling a valve main body 302 and a solenoid 203. Also in this embodiment, the body 305, the core 246, the case 56, and the end member 58 form the entire body of the control valve 301.

  The port 14 is provided at the upper end opening of the body 305, and the port 12 is provided at the side. An annular strainer 315 is also attached to the port 12. The strainer 315 includes a filter for suppressing entry of foreign matter into the body 305. A sub valve hole 32 and a sub valve seat 34 are provided in the lower part of the working chamber 39. The sub-valve element 336 has a bottomed cylindrical shape, and has an engaging portion 237 on the upper bottom. The sub-valve element 336 is configured to be larger in the axial direction than the sub-valve element 236 of the second embodiment, and defines the working chamber 39 inside thereof. The sub-valve element 336 is slidably supported in a guide hole 325 provided in the upper part of the body 305, and is operable in the axial direction. The lower end opening of the sub valve body 336 is attached to and detached from the sub valve seat 34 to open and close the sub valve. A plurality of communication holes 340 for allowing the port 14 and the working chamber 39 to communicate with each other are provided in the peripheral portion of the upper bottom portion of the sub valve body 336. When the auxiliary valve is opened, the refrigerant introduced from the crank chamber through the port 12 is relieved to the suction chamber through the auxiliary valve, the working chamber 39, the communication hole 340, and the port 14, thereby exhibiting a bleed function. Is done.

  In the present embodiment, the effective pressure receiving diameter D (seal portion diameter) of the sliding portion with the guide hole 325 of the sub valve body 336 and the effective pressure receiving diameter E (seal portion diameter) of the sub valve of the sub valve body 336 are as follows. Equally set (corresponds to “cancel structure”). For this reason, the influence of the crank pressure Pc and the suction pressure Ps acting on the auxiliary valve body 336 is cancelled.

  Also in this embodiment, the same effect as 2nd Embodiment can be acquired. Further, since the differential pressure (Pc−Ps) between the crank pressure Pc and the suction pressure Ps does not act on the sub-valve body 336, the force in the valve closing direction that acts on the sub-valve body 336 is substantially only the load of the spring 240. It becomes. That is, since the opening / closing operation of the sub valve body 336 does not depend on the refrigerant pressure, the set value of the solenoid force (that is, the current set value) for opening the sub valve can be accurately set based on the load of the spring 240. it can. Furthermore, since the port 12 into which the crank pressure Pc is introduced and the port 18 from which the crank pressure Pc is derived are arranged close to each other, these ports can be connected to a common passage on the compressor side. That is, the passage structure on the compressor side can be simplified.

  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.

  Although not described in the first embodiment, the port 16 and the port 18 shown in FIG. That is, as a port arranged opposite to the main valve body 30, a port for introducing the discharge pressure Pd is disposed on a side relatively close to the solenoid 3, and a port for deriving the crank pressure Pc on a relatively remote side. May be provided.

  Although not described in the first embodiment, a lock release mechanism similar to that in the second and third embodiments may be provided. Conversely, the lock release mechanism in the second and third embodiments may be omitted.

  Although not described in the above embodiment, the operating rods 38 and 238 and the transmission member 33 may be fixed. Or you may integrally mold the transmission part which functions similarly to the transmission member 33 at the front-end | tip part of the actuating rod 38,238.

  In the above-described embodiment, a so-called Ps detection valve that operates by directly detecting the suction pressure Ps by arranging the power element in the working chamber that satisfies the suction pressure Ps is exemplified as the control valve. In the modified example, the power element is disposed in the capacity chamber that is filled with the crank pressure Pc, while adopting a structure that cancels the crank pressure Pc, the Ps sensing valve that operates by substantially sensing the suction pressure Ps. It may be configured.

  In each of the above embodiments, the so-called Ps sensing valve that senses the suction pressure Ps as the sensed pressure is shown as the control valve. However, the control valve may be configured as a so-called Pc sensing valve that senses the crank pressure Pc. In that case, the port 14 is communicated with the crank chamber.

  In the said embodiment, although the example which employ | adopts the bellows 45 and 245 as a pressure sensitive member which comprises the power elements 6 and 206 was shown, you may employ | adopt a diaphragm. In this case, a plurality of diaphragms may be connected in the axial direction in order to ensure an operation stroke necessary for the pressure sensitive member.

  In the above embodiment, the spring (coil spring) is exemplified as the biasing member for the springs 40, 42, 44, 88, 240 and the like, but an elastic material such as rubber or resin or an elastic mechanism such as a leaf spring is adopted. Needless to say.

  In the above embodiment, the reference pressure chamber S inside the bellows 45, 245 is in a vacuum state, but it may be filled with air or with a predetermined gas as a reference. Alternatively, any one of the discharge pressure Pd, the crank 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, 14, 16, 18 port, 20 main valve hole, 22 main valve seat, 30 main valve body, 31 valve seat forming member, 32 sub Valve hole, 33 Transmission member, 34 Sub valve seat, 36 Sub valve body, 38 Acting rod, 39 Acting chamber, 40, 42 Spring, 43 Internal passage, 44 Spring, 45 bellows, 201 Control valve, 202 Valve body, 203 Solenoid , 205 body, 206 power element, 230 main valve body, 236 sub-valve body, 238 actuating rod, 240 spring, 245 bellows, 301 control valve, 302 valve body, 305 body, 336 sub-valve body.

Claims (7)

Control for 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 crank chamber A valve,
A body formed with a main passage for communicating the discharge chamber and the crank chamber, and a sub-passage for communicating the crank chamber and the suction chamber;
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;
A power element that includes a pressure-sensitive member that senses a predetermined sensed pressure and displaces in the opening and closing direction of the main valve, and can apply a driving force in the valve-opening direction to the main valve body according to the displacement of the pressure-sensitive member When,
A solenoid capable of generating a force that opposes the driving force of the power element by energization;
An actuating rod disposed between the power element and the solenoid for transmitting the force of the solenoid to the power element;
An auxiliary valve seat provided in the auxiliary passage;
A sub-valve element that opens and closes the sub-valve by attaching and detaching to the sub-valve seat;
A biasing member that biases the sub-valve element in the valve closing direction;
With
In a state where the control current of the main valve is supplied to the solenoid, the sub-valve element is seated on the sub-valve seat and functions as a fixed end of the power element, and the solenoid has a set value larger than the control current. The variable displacement compression is characterized in that the biasing force of the biasing member is set so that the sub-valve element can be separated from the sub-valve seat and integrally displaced with the power element when the above current is supplied. Control valve for machine.   2. The control valve for a variable capacity compressor according to claim 1, wherein the sub-valve body is integrally provided at an end portion of the power element opposite to the operation rod. Another urging member for urging the main valve body in the valve closing direction;
The main valve body is provided with an internal passage extending in the axial direction,
2. The structure according to claim 1, wherein the operating rod is provided so as to be inserted through the internal passage, and is configured to be capable of being integrally displaced or relatively displaced with the main valve body according to an operating state of the power element. 2. A control valve for a variable capacity compressor according to 2. The power element is disposed in a working chamber that is partitioned by the sub-valve body and that satisfies the suction pressure of the suction chamber,
The pressure sensitive member senses the suction pressure as the sensed pressure,
4. The variable displacement compression according to claim 3, wherein an internal passage of the main valve body and the working chamber communicate with each other, and an influence of the suction pressure that directly acts on the main valve body is substantially canceled. Control valve for machine. A transmission member provided between the pressure-sensitive member and the main valve body and capable of transmitting the driving force of the power element to the main valve body;
5. The control valve for a variable capacity compressor according to claim 4, wherein a communication hole for communicating the internal passage and the working chamber is provided in the transmission member.   The control valve for a variable capacity compressor according to any one of claims 1 to 5, further comprising a cancel structure for canceling an influence of pressure acting on the sub-valve element. The body includes a discharge chamber communication port for introducing the refrigerant in the discharge chamber into the main passage, a first crank chamber communication port for guiding the refrigerant having passed through the main valve to the crank chamber, and the crank A second crank chamber communication port for introducing the refrigerant of the chamber into the auxiliary passage, and a suction chamber communication port for deriving the refrigerant having passed through the auxiliary valve to the suction chamber,
The variable capacity according to any one of claims 1 to 6, wherein each port is disposed so that the first crank chamber communication port and the second crank chamber communication port are adjacent to each other in the body. Control valve for compressor.

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