JP4260037B2 - Expansion device - Google Patents

Description

  The present invention relates to an expansion device in which a solenoid valve and an expansion valve are integrated, and in particular, with a solenoid valve used in a rear side circuit of an automotive air conditioner capable of independently air-conditioning a front side and a rear side in a vehicle interior. The present invention relates to an expansion device.

  Conventionally, as an automotive air conditioner, a front evaporator and its expansion valve, a rear evaporator, and a rear-side air-conditioning control can be independently performed in a vehicle interior. A refrigeration cycle configured by arranging the expansion valve in parallel is used.

  These expansion valves often use temperature-type expansion valves that sense the outlet temperatures of the refrigerant discharged from the front and rear evaporators and control the flow rate of the refrigerant supplied to the front and rear evaporators. . In the temperature type expansion valve, the power element senses the refrigerant outlet temperature of the front and rear evaporators, and controls the lift amount of the valve body arranged on the upstream side of the valve seat by the shaft extending through the valve hole. It is configured. Since the valve body is arranged on the upstream side of the valve seat, the high-pressure refrigerant introduced from the condensed air acts on the valve body in the valve closing direction. For this reason, if there is a sudden increase in the pressure of the refrigerant and a load is applied to the valve body in the valve closing direction, a water hammer phenomenon occurs in which the valve closes and the pressure further increases, causing the valve body to self-vibrate. It may end up.

  Therefore, in order to suppress such self-excited vibration, a vibration control mechanism that applies a brake to the movement of the valve body has been proposed and put into practical use. As a vibration damping mechanism, for example, a mechanism that slows the movement of the shaft in the axial direction by applying a lateral load to the shaft that transmits the movement of the power element to the valve body is known. In other words, there is a structure in which an inclined contact surface is formed on the diaphragm receiving plate in the power element, and a shaft is contacted to the inclined contact surface to configure a vibration damping mechanism (for example, FIG. 1 of Patent Document 1). (See FIGS. 4 and 7.) In this vibration damping mechanism, the valve body applies a load in the valve closing direction due to an increase in the pressure of the refrigerant, so that the shaft applies a load obliquely to the inclined contact surface of the diaphragm receiving plate. Receives a lateral load and generates a sliding resistance due to friction with the body holding the shaft, making the valve body difficult to move. As another vibration damping mechanism, a lateral load is applied to the shaft using a spring, which generates sliding resistance with the body holding the shaft, making the valve body difficult to move and vibrating from the expansion valve. There is also one that does not generate sound (for example, see FIGS. 10 and 13 of Patent Document 1). As another vibration suppression mechanism, there is a mechanism in which a leaf spring is provided on a shaft or a valve body, and the leaf spring generates a sliding resistance for vibration suppression with the body (see, for example, Patent Document 2). .)

  When the front side refrigeration cycle is used in the refrigeration cycle using such an expansion valve in the front and rear evaporators, the rear refrigeration cycle is not necessarily used. Therefore, an electromagnetic valve that functions as a stop valve is provided in the rear circuit so that the refrigerant does not flow when the rear refrigeration cycle is not used.

As the electromagnetic valve and the expansion valve used for such applications, an expansion device with an electromagnetic valve in which they are integrated is proposed in view of their installation space, interconnection piping and cost (for example, patents). Reference 3).
JP 2003-307372 A US Pat. No. 4,542,852 (FIGS. 1 and 4) Japanese Patent Laid-Open No. 11-182983 (FIG. 2)

  However, even in an expansion device with an electromagnetic valve in which an electromagnetic valve and an expansion valve are integrated, in order to suppress self-excited vibration, it is necessary to give a sliding resistance to axial movement of the valve body or the shaft. There is a problem that the structure becomes complicated and the cost of parts increases. Further, the expansion valve is provided with an adjusting screw for adjusting the superheat characteristic, which causes a problem that the processing cost of the adjusting screw and the body becomes high.

  The present invention has been made in view of these points, and an object thereof is to provide an expansion device with an electromagnetic valve that can suppress self-excited vibration without increasing costs.

In the present invention, in order to solve the above problem, in the expansion device in which an expansion valve for adiabatically expanding the refrigerant and a stop valve for opening and closing the refrigerant passage are integrated, the expansion is performed according to the temperature and pressure of the refrigerant discharged from the evaporator. A power element that displaces in the opening and closing direction of the valve, and a driving force transmission member that extends from the power element through the valve hole of the expansion valve and is movable in the axial direction so as to transmit the displacement of the power element If, before the combined valve body for the power element opposite the expansion valve disposed retractably in the axial direction are guided by the driving force transmitting member in side and the check valve Kiben hole, wherein when energized A solenoid that switches the function so as to function as an expansion valve and function as the stop valve when de-energized, and the solenoid A first iron core that is slidably disposed in a sleeve extending in a linear direction and is fixed to an end of the driving force transmission member opposite to the power element; and A first spring that urges the driving force transmission member in contact with the power element by urging in the direction of the power element, and the first iron core while passing through the driving force transmission member in the sleeve. A second iron core that is slidably arranged on the power element side and is fixed to the dual-purpose valve body, and is arranged between the first iron core and the second iron core. A second spring that biases the dual-purpose valve body in a direction to close the valve hole, and the second spring pulls the second iron core away from the first iron core when the solenoid is not energized. Energizing in the direction away from the valve body The first iron core and the second iron core are electromagnetically coupled when energized, so that the displacement of the power element is the driving force transmission member and the first An expansion device is provided that functions as the expansion valve by transmitting to the dual-purpose valve body via an iron core and the second iron core .

  According to such an expansion device, the first iron core and the second iron core of the solenoid that transmits or blocks the displacement of the power element to the dual-purpose valve body guide these in such a manner that they can advance and retract in the axial direction. The sleeve is inscribed on the inner wall surface of the sleeve. As a result, when acting as an expansion valve by energizing the solenoid, the first iron core and the second iron core are driven and controlled by the power element while sliding on the inner wall surface of the sleeve. The self-excited vibration of the expansion valve can be suppressed by the frictional resistance.

  In the expansion device according to the present invention, the sliding friction generated between the first iron core and the second iron core and the inner wall surface of the sleeve constitutes a vibration damping mechanism that suppresses self-excited vibration. It is not necessary to mount parts for constituting the mechanism, and a vibration damping function can be added without increasing the cost.

  In addition, in order to adjust the degree of superheat of the expansion valve, an adjustment piece is press-fitted into the sleeve, and finally it is fixed to the sleeve by caulking. This eliminates the need for screw processing with a high processing cost, which is necessary for an adjustment mechanism using an adjustment screw, and thus a mechanism for adjusting the load of the first spring can be configured at low cost.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a system diagram of an automotive air conditioner to which an expansion device with a solenoid valve according to the present invention is applied.

  This automotive air conditioner can independently air-condition the front and rear sides of a passenger compartment, and includes a compressor 1, a condenser 2, a temperature type expansion valve 3, and a front evaporator 4. The refrigeration cycle of the front-side air conditioner is configured, and the expansion device 5 and the rear evaporator 6 having functions of a temperature type expansion valve and a stop valve are connected in parallel with the circuits of the expansion valve 3 and the front evaporator 4. Part of the refrigeration cycle of the rear air conditioner.

  The high-temperature and high-pressure refrigerant compressed by the compressor 1 is sent to the condenser 2, where it is heat-exchanged with the air outside the passenger compartment and condensed to become a liquid refrigerant. This liquid refrigerant is sent to the expansion valve 3 and the expansion device 5. In the expansion valve 3, the liquid refrigerant is adiabatically expanded to form a low-temperature / low-pressure gas-liquid mixed refrigerant and sent to the front evaporator 4. The front evaporator 4 evaporates the refrigerant sent from the expansion valve 3 by exchanging heat with the air in the front passenger compartment or the air outside the passenger compartment introduced into the passenger compartment, and the gas refrigerant evaporated here Is returned to the compressor 1. At this time, the expansion valve 3 detects the refrigerant temperature at the outlet of the front evaporator 4 and controls the refrigerant flow rate so that the refrigerant at the outlet has a predetermined degree of superheat.

  Similarly, in the expansion device 5, the liquid refrigerant condensed in the condenser 2 is adiabatically expanded to form a low-temperature / low-pressure gas-liquid mixed refrigerant and sent to the rear evaporator 6. The rear evaporator 6 evaporates the refrigerant sent from the expansion device 5 by exchanging heat with the air in the vehicle interior on the rear side, and the gas refrigerant evaporated here passes through the expansion device 5 and passes through the compressor 1. Returned to At this time, the expansion device 5 detects the temperature and pressure of the refrigerant discharged from the rear evaporator 6 and controls the refrigerant flow rate so that the refrigerant at the outlet has a predetermined degree of superheat.

When the rear-side air conditioner is not used, the expansion device 5 blocks the internal refrigerant passage so that the refrigerant does not flow through the rear-side circuit.
Next, a specific embodiment of the expansion device 5 according to the present invention will be described.

  FIG. 2 is a longitudinal sectional view showing a configuration example of the expansion device, and FIG. 3 is a partial cross-sectional side view of the expansion device as viewed from the side to which the pipes of the condenser and the compressor are connected. In FIG. 2, in order to simultaneously show a state that functions as a stop valve that blocks the refrigerant passage and a state that functions as a normal expansion valve whose opening degree is controlled, From the center of the figure, the right side shows the closed state when not energized, and the left side shows the state when functioning as an expansion valve when energized.

  The expansion device 5 according to the present invention includes a body 11 that houses the stop valve and the valve portion of the expansion valve, a power element 12 that senses the temperature and pressure of the refrigerant returned from the rear evaporator 6, and a stop valve function or expansion. And a solenoid 13 for switching the valve function.

  The body 11 includes a port 14 that receives high-temperature and high-pressure refrigerant from the condenser 2, a port 15 that supplies low-temperature and low-pressure refrigerant adiabatically expanded by the expansion device 5 to the rear evaporator 6, and rear evaporation. A port 16 for receiving the refrigerant returned from the container 6 and a port 17 for sending the refrigerant in the port 16 to the compressor 1 are provided.

  A valve seat 18 is formed integrally with the body 11 between the port 14 and the port 15. A first shaft 19 and a second shaft 20, which are driving force transmission members, are disposed on the central axis of the valve hole that forms the valve seat 18 so as to freely advance and retract in the axial direction. The upper end of the first shaft 19 abuts on the center disk 22 disposed on the lower surface of the diaphragm 21 of the power element 12, and the lower end abuts on the upper end of the second shaft 20 disposed through the valve hole. Has been. The lower end of the second shaft 20 is fixed to a first iron core 24 disposed in a non-magnetic sleeve 23 of the solenoid 13 so as to be movable back and forth in the axial direction. The second shaft 20 has the same outer diameter as the inner diameter of the valve hole, and the side in contact with the first shaft 19 is reduced in diameter.

  The second shaft 20 is provided with a second iron core 25 and a valve body guide 26 that can move forward and backward in the axial direction using this as a guide. The valve element guide 26 is fitted to the second iron core 25. At the tip of the valve element guide 26 on the power element 12 side, a spool-shaped dual-purpose valve element 27 that can advance and retreat in the axial direction is formed integrally with the reduced diameter portion of the second shaft 20 as a guide. 27 is provided with a ring-shaped valve seat 28 having flexibility. Thereby, the second iron core 25 to which the valve element guide 26 is fixed works as a movable iron core that drives the dual-purpose valve element 27. When the dual-purpose valve element 27 functions as the expansion valve, When the throttle part is configured to contact and separate from the valve seat 18 and functions as a stop valve, it is inserted into the valve hole to close the valve hole. When functioning as a stop valve, the valve seat 28 completely seals between the dual-purpose valve body 27 and the valve seat 18 so that the flow of the refrigerant can be completely stopped. Furthermore, when functioning as a stop valve, the second shaft 20 passes through a gap between the second iron core 25, which slides in the axial direction using this as a guide, the valve element guide 26 and the dual purpose valve element 27. In order to prevent internal leakage in which the refrigerant leaks to the downstream side of the valve portion, the V packing 29 of the seal member is formed in the space formed between the second iron core 25, the valve body guide 26, and the second shaft 20. Is arranged.

  A spring 30 for urging the first iron core 24 upward in the drawing is disposed in the sleeve 23 of the solenoid 13. The spring 30 ensures that the second shaft 20 fixed to the first iron core 24, the first shaft 19, and the center disk 22 of the power element 12 are always in contact with each other. The spring 30 is received by an adjustment piece 31 that is press-fitted from the open end of the sleeve 23, and the load of the spring 30 is adjusted by adjusting the amount of press-fitting of the adjustment piece 31. The adjustment piece 31 is finally fixed to the sleeve 23 by caulking the sleeve 23 from its outer periphery, and the expansion device 5 becomes an expansion valve set to a desired degree of superheat. Compared with the case where an adjustment screw is used to adjust the load of the spring 30, this load adjustment mechanism eliminates the need for screw processing with a high processing cost on the adjustment screw, and even for a thin sleeve 23 that receives the adjustment screw. Since it is not necessary to perform threading which is difficult to process, it can be configured at low cost.

  A spring 32 is also disposed between the first iron core 24 and the second iron core 25. The spring 32 urges the second iron core 25 in a direction away from the first iron core 24 when the solenoid 13 is not energized, and thereby the dual-purpose valve body 27 held by the second iron core 25. The valve seat 28 provided on the valve seat is always seated on the valve seat 18 so that the fully closed state can be maintained.

  An electromagnetic coil 33 is provided around the outside of the sleeve 23, and the electromagnetic coil 33 is surrounded by a yoke 34 and a plate 35. As shown in FIG. 3, the yoke 34 is fixed to the body 11 by caulking a shoulder portion formed by recessing the body 11 as shown in FIG. ing. The through holes 36 and 37 formed through the body 11 are mounting holes through which bolts for fixing the plate holding the end of the pipe extending from the rear evaporator 6 to the body 11 are passed through the expansion device 5. The stud bolts 38 and 39 implanted in the body 11 are for fixing the plate holding the ends of the pipes connected to the compressor 1 and the condenser 2 to the body 11.

  In this way, the solenoid 13, which forms the magnetic circuit with the electromagnetic coil 33, the yoke 34, the plate 35, the first iron core 24, and the second iron core 25, is energized with the first iron core 24. By having the second iron core 25 adsorbed and having the function of electromagnetically coupling the dual-purpose valve body 27 and the second shaft 20, the dual-purpose valve element 27 and the second shaft 20 are coupled to each other. The displacement of the diaphragm 21 of the power element 12 is transmitted to the dual-purpose valve body 27, so that the opening degree can be controlled.

  In the expansion device 5 having the above configuration, when the rear air conditioner is not used, the solenoid 13 is in a non-energized state. For this reason, the second iron core 25 is urged away from the first iron core 24 by the spring 32, so that the valve seat 28 held by the dual purpose valve body 27 is seated on the valve seat 18. As a result, the expansion device 5 functions as a stop valve and the internal refrigerant passage is blocked, so that the refrigerant does not flow into the rear circuit.

  Next, when using the rear air conditioner, the solenoid 13 is energized. As a result, the first iron core 24 and the second iron core 25 are sucked and adsorbed to each other, so that the dual-purpose valve element 27 is indirectly fixed to the second shaft 20. At this time, since the second iron core 25 moves toward the first iron core 24, the dual-purpose valve element 27 comes out of the valve hole and the valve seat 28 is separated from the valve seat 18. As a result, the high-temperature and high-pressure refrigerant supplied from the condenser 2 to the port 14 flows to the port 15 through the gap between the dual-purpose valve element 27 and the valve seat 18. At this time, the high-temperature and high-pressure refrigerant is adiabatically expanded to become a low-temperature and low-pressure refrigerant and is sent from the port 15 to the rear evaporator 6.

  In the rear evaporator 6, the refrigerant supplied from the expansion device 5 is evaporated by exchanging heat with the air in the vehicle interior on the rear side, and the evaporated refrigerant is returned to the expansion device 5. In the expansion device 5, the refrigerant returned from the rear evaporator 6 enters the port 16 and is returned from the port 17 to the compressor 1. At this time, in the expansion device 5, the diaphragm 21 of the power element 12 senses the temperature and pressure of the refrigerant that has passed, and the displacement of the diaphragm 21 in accordance with the temperature and pressure of the refrigerant is detected by the first shaft 19 and the second shaft 20. And it transmits to the combined valve body 27 via the 1st and 2nd iron cores 24 and 25, and controls a refrigerant | coolant flow volume.

  Here, when the expansion device 5 operates as an expansion valve, a current is passed through the electromagnetic coil 33 to adsorb the first iron core 24 and the second iron core 25. At this time, the first iron core 24 and the second iron core 25 are not only attracted to each other, but are also attracted to the yoke 34 and the plate 35. The first iron core 24 and the second iron core 25 are not supported in a state of being concentric with the sleeve 23, but are merely disposed in the sleeve 23. Therefore, the yoke 34 and the plate A portion of the outer peripheral surface is always pressed against the inner wall surface of the sleeve 23 by the suction force between the sleeve 35 and the outer surface 35. Thus, when the first iron core 24 and the second iron core 25 are about to move in the axial direction within the sleeve 23, the first iron core 24 and the second iron core 25 and the inner wall surface of the sleeve 23 Since the sliding friction is generated during this period, the self-excited vibration in which the dual-purpose valve body 27 freely vibrates in the opening / closing direction due to the rapid pressure fluctuation of the high-pressure refrigerant can be suppressed by the sliding friction. That is, in this expansion device 5, the first iron core 24 and the second iron core 25 are inscribed in the inner wall surface of the sleeve 23 to generate frictional resistance due to sliding, so that self-excited vibration is generated. This makes it possible to configure the vibration damping mechanism without requiring special parts for suppression.

  In this embodiment, the valve seat 28 is provided on the side of the dual-purpose valve element 27, but it is needless to say that the valve seat 28 may be provided on the side of the valve seat 18. The expansion device with a solenoid valve of the present invention is not applied to a refrigeration cycle using a specific refrigerant, but can be applied to a refrigeration cycle using any kind of refrigerant. Furthermore, in the above embodiment, the case where the expansion device with a solenoid valve according to the present invention is applied to the temperature type expansion valve of the rear side air conditioner has been described as an example, but the temperature type expansion valve of the front side air conditioner, Or it can also apply as a temperature type expansion valve of both a front side and rear side air conditioner.

1 is a system diagram of an automotive air conditioner to which an expansion device with a solenoid valve according to the present invention is applied. It is a longitudinal cross-sectional view which shows the structural example of an expansion apparatus. It is the partial cross section side view which looked at the expansion | swelling apparatus from the side to which piping with a condenser and a compressor is connected.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Condenser 3 Expansion valve 4 Front evaporator 5 Expansion device 6 Rear evaporator 11 Body 12 Power element 13 Solenoid 14, 15, 16, 17 Port 18 Valve seat 19 First shaft 20 Second shaft DESCRIPTION OF SYMBOLS 21 Diaphragm 22 Center disk 23 Sleeve 24 1st iron core 25 2nd iron core 26 Valve body guide 27 Valve body 28 Valve seat 29 V packing 30 Spring 31 Adjustment piece 32 Spring 33 Electromagnetic coil 34 York 35 Plates 36, 37 Through hole 38, 39 Stud bolt

Claims (7)

In an expansion device in which an expansion valve for adiabatically expanding the refrigerant and a stop valve for opening and closing the refrigerant passage are integrated,
A power element that is displaced in the opening and closing direction of the expansion valve in accordance with the temperature and pressure of the refrigerant that has left the evaporator;
A driving force transmission member extending from the power element through the valve hole of the expansion valve and arranged to be movable forward and backward in the axial direction so as to transmit the displacement of the power element ;
And the power element and the combined valve body for the driving force is guided by the transmission member the expansion valve and the stop valve arranged to freely advance and retreat in the axial direction on the opposite side of the front Kiben hole,
A solenoid that switches the function so that it functions as the expansion valve when energized and functions as the stop valve when de-energized,
The solenoid is slidably disposed in a sleeve extending in the axial direction of the driving force transmission member, and is fixed to an end of the driving force transmission member opposite to the power element. And a first spring that urges the first iron core in the direction of the power element so that the driving force transmission member always contacts the power element, and the driving force transmission member in the sleeve. A second iron core that is slidably disposed on the power element side from the first iron core while being penetrated, and is fixed to the dual-purpose valve body, the first iron core, and the second iron core A second spring that is disposed between the iron core and biases the dual-purpose valve body in a direction to close the valve hole,
As the stop valve, the second spring biases the second iron core in a direction away from the first iron core when the solenoid is not energized to maintain the dual-purpose valve body in a closed state. When functioning, the first iron core and the second iron core are electromagnetically coupled to each other so that the displacement of the power element is the driving force transmission member, the first iron core, and the second iron core. An expansion device that functions as the expansion valve by transmitting to the dual-purpose valve body via a valve .   The driving force transmission member has one end that is in contact with the power element and the same diameter as the inner diameter of the valve hole of the expansion valve, passes through the valve hole and contacts the first shaft. A second shaft having a reduced diameter portion at one end in contact with the second shaft and urging the other end of the first shaft by the first spring, and the second shaft includes: The expansion device according to claim 1, wherein the second iron core is guided on the first iron core side, and the dual-purpose valve body is guided by the reduced diameter portion so as to advance and retract in the axial direction.   The expansion device according to claim 2, wherein a seal member is disposed between the dual-purpose valve body and the second shaft.   2. The expansion device according to claim 1, wherein a flexible valve seat for completely stopping the flow of the refrigerant is provided on the dual-purpose valve body or a valve seat on which the dual-purpose valve body is seated.   The expansion device according to claim 1, wherein a load of the first spring is adjusted by a press-fitting amount of an adjusting piece press-fitted into the sleeve.   6. The expansion device according to claim 5, wherein the adjustment piece that adjusts the load of the first spring is fixed to the sleeve by caulking the sleeve. The expansion device according to claim 1, wherein the solenoid is fixed to a body of the expansion valve by caulking the yoke.

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