JP2000179739A - Combined solenoid valve and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To act a rear side expansion function of a car cooler by attaching two solenoid valves on one valve body, and performing ON/OFF control of two solenoid valves. SOLUTION: In a valve body 8 composed of first and second circulation passages 2, 4, chambers 5, 5a communicated with the first circulation passage 2, valve seats 6, 6a disposed on bottom parts of the chambers 5, 5a, a large valve port 7 communicated with the first circulation passage 2, and a small valve port 7a communicated with the second circulation passage 4, a first solenoid valve 18 is arranged on an inlet side of a refrigerant, and a second solenoid valve 19 is arranged on an outlet side of the refrigerant. A refrigerant flow rate is controlled step by step by ON/OFF control of the first and second solenoid valves 18, 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for a vehicle, in which an air conditioning unit having a built-in evaporator for a refrigeration cycle is provided on both the front side and the rear side in a vehicle compartment. The present invention relates to a composite solenoid valve which fulfills the expansion function of the above.

[0002]

2. Description of the Related Art Conventionally, evaporators for cooling have been provided in air conditioning units before and after a vehicle cabin, for example, in order to independently perform air conditioning control on a front side and air conditioning control on a rear side in a vehicle interior. In addition, there has been known a refrigeration cycle for vehicle air conditioning, in which two cooling evaporators and expansion valves for reducing the pressure of refrigerant flowing into these evaporators are arranged in parallel. In this refrigerating cycle, an electromagnetic valve is installed in series with the expansion valve to switch the flow of the refrigerant to these evaporators.

FIG. 5 shows an entire configuration of a refrigeration cycle to which a conventional solenoid valve-integrated expansion valve is applied. The refrigeration cycle of FIG. 5 can be independently controlled on a front seat side and a rear seat side of a vehicle. It is used for a vehicle air conditioner having a simple air conditioning unit.

In the refrigeration cycle shown in FIG.
Compresses the suction refrigerant and discharges it as a high-temperature and high-pressure gas refrigerant. The condenser 31 cools and condenses the gas refrigerant discharged from the compressor 30, and the condensed liquid refrigerant flows into the liquid receiver 32.

The liquid refrigerant is supplied to the gas-liquid 2
First and second expansion valves 33 and 34 for reducing the pressure to expand into a phase state
And first and second evaporators 35 and 36 for evaporating the refrigerant passing through the first and second expansion valves 33 and 34 are arranged in parallel with each other. Here, the first expansion valve 33 and the first evaporator 35 are provided in a front air-conditioning unit 37 arranged on an instrument panel in a front part of the vehicle interior, and are used for air conditioning on a front seat side in the vehicle interior. Used for First expansion valve 3
As is well known, reference numeral 3 denotes a temperature-type expansion valve whose valve opening is automatically adjusted so as to maintain the superheat degree of the refrigerant at the outlet of the first evaporator 35 at a predetermined value. It has a temperature sensing part 33a that senses the temperature of the refrigerant and changes the internal refrigerant pressure.

On the other hand, the second expansion valve 34 and the second evaporator 36 are provided in a rear air-conditioning unit 38 arranged at the rear of the vehicle interior, for example, at the ceiling of a wagon-type automobile, and a rear seat in the vehicle interior is provided. Used for side air conditioning. The refrigerant outlet sides of the first and second evaporators 35 and 36 are merged and connected to the suction side of the compressor 30. The second expansion valve 34 is a solenoid valve-integrated expansion valve in which the temperature expansion valve 34 having the diaphragm type actuator 39 and the solenoid valve 40 are integrated. In addition, R is a pressure introduction channel.

FIG. 6 is a longitudinal sectional view of the above-described solenoid valve-integrated expansion valve expansion valve. The solenoid valve-integrated expansion valve 34 includes a normally-closed solenoid valve 40 that shuts off the flow of refrigerant to the rear cooler side.
It has.

The temperature-type expansion valve 34 includes a diaphragm-type actuator 39 for sensing the temperature of the refrigerant in the low-pressure refrigerant flow path and controlling the flow rate, a prismatic valve body 41 made of metal such as aluminum, and a low-pressure expansion valve. A temperature sensing rod 42 for sensing the temperature of the refrigerant in the refrigerant flow path, an operating rod 43, a spherical valve element 44, and a spring mechanism 4 for applying a predetermined spring force to the valve element 44.
5 and a metal plug 46.

The prismatic valve body 41 is provided with a refrigerant inlet 4
7 (indicated by a two-dot chain line), a refrigerant outlet 48 and a low-pressure refrigerant channel 49 are provided. Further, a stepped inner hole 50 is formed in the center of the valve body 41, and a small diameter portion of the hole is used as a pressure chamber 51. A temperature sensing rod 42 having an upper end formed in a large-diameter portion 42a is inserted into the stepped inner hole 50, and the large-diameter portion 42a is disposed in a pressure equalizing chamber 57 described later. Further, a communication hole 52 is provided between the refrigerant outlet 48 of the valve body 41 and the pressure chamber 51, and the refrigerant at the outlet 48 is connected to the communication hole 52 → the pressure chamber 51 → the communication hole of the temperature sensing rod. 42b → connected to the pressure equalizing chamber 60. Further, the valve body 41 is provided with a communication chamber 53 connected to the solenoid valve 40 side, and the communication chamber 53 is provided with a communication hole 55.
→ Throttle channel 56 for decompressing and expanding the high-pressure side liquid refrigerant →
It is connected to the outlet refrigerant passage 55 via the gap 57. Incidentally, 54a, 54b and 55 are outlet refrigerant passages. 58 is a valve seat.

The diaphragm-type actuator 39 constitutes a valve body operating mechanism. The diaphragm actuator 39 includes upper and lower two casings 59 and 60, and a diaphragm 61 that is a pressure responsive member. The diaphragm actuator 39 is air-tightly fixed to the valve body 41 by screwing. ing. Further, the internal space of both casing members 59 and 60 is partitioned by a diaphragm 61 into a temperature sensing chamber (first pressure chamber) 62 and a pressure equalizing chamber (second pressure chamber) 63. In the upper temperature sensing chamber 62, the same refrigerant as the refrigeration cycle circulation refrigerant is sealed by a capillary tube 64 at a predetermined pressure.

The temperature sensing rod 42 has a communication hole 42b penetrating the center thereof in the axial direction, and a groove 42c having a U-shaped cross section is provided at the lower end of the temperature sensing rod 42. Even if the lower end of the temperature sensing rod 42 is in contact with the upper end of the operating rod 43, the pressure chamber 51 is always in communication with the communication hole 42b through the groove 42c. The large diameter portion 42 a of the temperature sensing rod 42 is arranged in the pressure equalizing chamber 63.

The spring mechanism 45 is provided with the stepped inner hole 5.
0, is housed in a housing chamber 65 formed below,
The spring mechanism 45 includes a spherical valve body 44 made of stainless steel.
And a metal support plate 66 joined to it by welding or the like, and a coil spring (spring means) 67. The accommodation chamber 65 communicates with the refrigerant inlet 47 into which the high-pressure liquid refrigerant flows.

On the other hand, the normally closed solenoid valve 40 has a substantially disc-shaped valve body 69 having a fine valve hole 68 formed in the center thereof,
This is a pilot-type solenoid valve provided with an electromagnet 70 and a cylindrical plunger 71 made of a magnetic material, wherein the valve body 69 is formed of a resin member. Also, this valve element 6
A piston member 72 formed of a metal such as brass is arranged on the outer peripheral portion of 9, and both are integrally connected by means such as caulking.

The mounting screw member 73 made of a non-magnetic metal is
It is detachably screwed and fixed to the valve body 41,
The piston member 72 is slidably fitted in the inner peripheral portion of the mounting screw member 73 in the left-right direction.

The electromagnet 70 has a bobbin 75 made of resin wound around a solenoid 74.
A cylindrical magnetic pole member 76 is coaxially fitted in the hollow distal end portion, and the magnetic pole member 76 is fastened and fixed to a magnetic frame 77 made of a magnetic material by screws.

The plunger 71 has a valve portion 71a that protrudes in a conical shape on the end face on the valve body 69 side. And
The plunger 71 is urged by the coil spring 78 toward the valve body 69, and the valve portion 71 a is seated in the valve hole 68 of the valve body 69, thereby closing the valve hole 68.

A back pressure chamber 79 is formed between the end face of the plunger 71 on the valve portion 71a side and the valve body 69, and a minute pressure for constantly communicating between the back pressure chamber 79 and the communication chamber 53. A hole 80 is provided in the valve body 69. In the normally-closed solenoid valve 40 configured as described above, when the solenoid is energized and generates magnetic flux, the plunger 71 is attracted by the magnetic pole member 76 against the coil spring 78, and the valve portion 71a And the valve hole 68 is opened. Then, the back pressure chamber 79 communicates with the coolant outlet 48 through the coolant channel 53, and the pressure in the back pressure chamber 79 decreases to the pressure on the coolant outlet 48 side.

Next, the operation of a conventional expansion valve integrated with a solenoid valve used for a rear cooler will be described. In FIG. 3, when the compressor 30 operates by receiving power from an engine of the vehicle via an electromagnetic clutch, the compressor 30 sucks and compresses the refrigerant in the downstream flow passages of the evaporators 35 and 36, and compresses the high-temperature and high-pressure. Is discharged toward the condenser 31. Then, the gas refrigerant is cooled and condensed in the condenser 31.

The condensed refrigerant then flows into the liquid receiver 32, where the refrigerant gas and liquid are separated, the liquid refrigerant flows out of the liquid receiver 32, and the first and second liquid refrigerants are arranged in parallel. Expansion valve 33, 3
Head to side 4. Here, when no occupant is on the rear seat side of the vehicle, the rear air conditioning unit 38 is not operated because there is no need to air-condition the rear seat side. Therefore, energization of the solenoid of the solenoid valve 40 is cut off,
The valve body 69 is in the valve closed state, and the refrigerant outlet 48 is closed. For this reason, the inlet-side refrigerant flow path of the second evaporator 36 is closed, and the refrigerant does not circulate.

Therefore, when the solenoid valve 40 is closed, the high pressure side acts on the pressure equalizing chamber 63 and the high pressure side pressure is sufficiently higher than the refrigerant saturation pressure at room temperature. Even if the temperature of the temperature 62 rises to about room temperature, the pressure in the pressure equalizing chamber 63 becomes sufficiently higher than the pressure in the temperature sensing chamber 62. As a result, the diaphragm 61 of the diaphragm actuator 39 is elastically deformed upward in FIG. 4, and accordingly, the valve body 44, the operating rod 43, and the temperature sensing rod 42 are moved by the spring force of the coil spring 67 in FIG. The valve body 44 is displaced upward, and the valve body 44 is seated on the valve seat surface 58 to be in a closed state.

Next, as described above, the valve element 44 of the expansion valve 34
When the solenoid of the solenoid valve 40 is energized in order to operate the rear air conditioning unit 38 in a state in which the valve is closed, the valve body 69 of the solenoid valve is opened, and the refrigerant flow paths 54a, 54
b opens. However, at this time, the valve element 4 of the expansion valve 34
Since the valve 4 is closed, a large flow of refrigerant does not suddenly start flowing when the solenoid valve 40 is opened.

That is, the pressure in the pressure equalizing chamber 63 of the diaphragm actuator 39 gradually decreases to the low pressure side pressure through the above-described pressure introduction flow path after the solenoid valve 40 is opened. The opening of the body 44 also gradually increases, and as a result, the flow rate of the refrigerant passing through the expansion valve 34 also gradually increases. Therefore, when the solenoid valve 40 is opened, noise due to sudden pressure fluctuations around the valve body 44 of the expansion valve 34 and flow noise (water hammer phenomenon) due to a sudden flow of a large flow refrigerant are effectively generated. It has the advantage that it can be suppressed.

When a predetermined time elapses after the solenoid valve 40 is opened, the pressure in the pressure equalizing chamber 63 of the diaphragm actuator 39 is increased by the refrigerant pressure on the inlet side of the second evaporator 36 (the refrigerant pressure on the inlet side of the evaporator). Thereafter, the low-pressure pressure on the evaporator inlet side applied to the pressure equalizing chamber 63 and the temperature-sensitive chamber 62
The valve element 44 of the expansion valve 34 is located at a position corresponding to the pressure difference between the refrigerant pressure corresponding to the refrigerant temperature at the evaporator outlet and the spring force of the coil spring 67 of the spring mechanism 45.
Is displaced.

Thus, the valve body 44 of the expansion valve 34 adjusts the degree of opening of the throttle passage 56 to adjust the flow rate of the refrigerant so that the refrigerant at the evaporator outlet maintains a predetermined degree of superheat. That is,
The expansion valve 34 is an internal pressure equalization type expansion valve that adjusts the flow rate of the refrigerant.

As described above, the conventional expansion valve integrated with a solenoid valve has a compact design, and when the solenoid valve is opened, noise due to sudden pressure fluctuations before and after the valve element of the expansion valve,
There is an advantage that generation of flow noise (water hammer phenomenon) due to a rapid flow of a large flow refrigerant can be effectively suppressed.

[0026]

However, the structure on the side of the expansion valve is formed of a diaphragm-type actuator 39 for controlling the flow rate by sensing the refrigerant temperature in the low-pressure refrigerant flow path, and a metal such as aluminum. A prismatic valve body 41,
A temperature sensing rod 42 for sensing the refrigerant temperature in the low-pressure refrigerant flow path, an operating rod 43, a spherical valve element 44, a spring mechanism 45 for applying a predetermined spring force to the valve element 44, and a metal plug 46, and the structure on the solenoid valve side includes a substantially disk-shaped valve body 69, an electromagnet 70, a cylindrical plunger 71 made of a magnetic material, and caulking or the like on the outer peripheral portion of the valve body 69. A piston member 72 made of a metal such as brass and the like, a mounting screw member 73 made of a non-magnetic metal, a columnar magnetic pole member 76, a magnetic frame 77 made of a magnetic material, and a coil spring 78 There is a problem that the structure is complicated and the cost is high because of the configuration. Also, in the temperature sensing chamber 62 of the diaphragm type actuator,
Generally, helium gas is mixed with the above-mentioned refrigerant gas and sealed at a volume ratio of 9: 1. This is to make the security inspection easy. However, in order to detect an extremely small amount of leak, the refrigerant gas leaked from the temperature sensing chamber 62 within a certain period is detected and its airtightness is detected. However, for example, there is a problem in that measurement cannot be performed after an extremely long period of time, such as several tens of days, and the product lead time becomes longer.

[0027]

SUMMARY OF THE INVENTION The present invention has been made in view of the problems of a conventional expansion valve integrated with a solenoid valve, and more particularly, relates to a composite electromagnetic valve having an expansion function as a rear side evaporator. The configuration is achieved by attaching two solenoid valves to one valve body having a first flow passage and a second flow passage, and operating the two solenoid valves by an ON / OFF control circuit with delay control added. Refrigerant flow rate can be controlled step by step,
It is another object of the present invention to provide a composite solenoid valve and a composite solenoid valve which can be produced at a low cost and which does not cause flow noise (water hammer phenomenon) during a valve opening operation to a valve closing operation.

That is, according to the first aspect of the present invention, the first flow path 2 connected to the inflow port 1, the second flow path 4 connected to the outflow port 3, and the chamber connected to the first flow path 2 are provided. 5 and 5a, valve seats 6 and 6a provided at the bottom of the chambers 5 and 5a, and a large valve port 7 communicating with the first flow passage 2 and the second flow passage 4 A valve body 8 having a small valve opening 7a, a non-magnetic plunger tube 9 and 9a fixed to the upper surface of the valve body 8 at a distance, and a lower end fixed to the plunger tubes 9 and 9a. Attraction portions 11 and 11a having elastic packings 10 and 10a fixed thereto, and insertion holes 12 and 12a for upper coil springs, and elastic valve packings 13 and 13a provided at a lower end portion of the plunger tube. 9 and the plunger 14 and 14a were interpolated slidably within 9a vertically, the compression coil spring biases the plunger 14 and 14a downwards 1
5 and 15a, the electromagnetic coils 16 and 16a, and the housing 17 made of a magnetic material form a first electromagnetic valve 18 on the inlet side of the refrigerant and a second electromagnetic valve 19 on the outlet side of the refrigerant. ON / O of the first solenoid valve 18 and the second solenoid valve 19
A composite solenoid valve characterized in that the flow rate of refrigerant can be controlled stepwise by FF control.

According to the present invention, the flow rate of the refrigerant can be controlled stepwise by mounting two solenoid valves on one valve body and operating the two solenoid valves by the ON / OFF control circuit with delay control added. Thus, a composite solenoid valve as an expansion valve for a rear cooler can be obtained at low cost.

According to a second aspect of the present invention, the valve packings 13 and 13a are provided with notches 21 and 21a at the outer peripheral edges of the upper surfaces, and the lateral grooves 22 and 22a are formed at the upper surfaces.
And a plurality of vertical grooves 23 and 23a on the side surface,
The composite solenoid valve according to claim 1, wherein the plungers (14, 14a) are provided with vertical holes (20, 20a) at the center thereof.

According to the present invention, when the refrigerant gas is introduced into the chambers 5, 5 ', 5a, 5a', the vertical holes 20, 20a of the plungers 14, 14a and the valve packing 13,
The chambers 5 and 5 'and the chambers 5a and 5a' are defined by the horizontal grooves 22 and 22a and the vertical grooves 23 and 23a of 13a.
And the pressure is always equalized and the force is canceled, and the refrigerating machine oil mixed in the refrigerant gas is prevented from flowing downward to accumulate in the chambers 5 ′ and 5a ′. And the plungers 14, 14a can be easily slidable in the vertical direction.

Further, the invention according to claim 3 is characterized in that the first solenoid valve 18 and the second solenoid valve 19 are provided side by side, and the two solenoid coils 16, 16a are integrally molded. 2. The composite solenoid valve according to claim 1, wherein:

According to the present invention, two electromagnetic coils 1
Since the moldings 6 and 16a are integrally molded, the cost can be reduced.

Further, according to the invention of claim 4, in controlling the flow rate of the refrigerant in a stepwise manner in the composite solenoid valve of the first aspect, when a large flow rate of the refrigerant is stopped, (a) a large valve port is provided. The fact that the first solenoid valve 18 and the second solenoid valve 19 having a small valve port are turned on and in the open state is as follows: (b) First, the first solenoid valve 18 is turned off and the large valve port 7 is closed. Next, when the second solenoid valve 19 is turned OFF after a few seconds and the small valve port 7a is closed to stop the refrigerant flowing from the first passage 2 to the second passage, and to stop the medium flow refrigerant,
(C) The second solenoid valve 19 having a small valve port is turned off and the first solenoid valve 18 having a large valve port is turned on to open the valve, and the refrigerant flows into the inlet port 1 → the large valve port 7 → the second. (D) Once the first solenoid valve 1
8 and the second solenoid valve 19 are turned on to allow a large flow of refrigerant to flow therethrough. (E) Next, the first solenoid valve 18 is turned off to close the large valve port 7, and then delayed for a few seconds. Second solenoid valve 19
Is turned off, the small valve port 7a is closed to stop the refrigerant flowing from the first passage 2 to the second path, and to stop the small flow of the refrigerant, (f) a first solenoid valve having a large valve port 18
Is OFF and the second solenoid valve 18 having a small valve port is O
N, the valve is opened and the refrigerant flows from the inlet 1 → the first flow passage 2 → the small valve port 7a. Close valve 1
A refrigerant flowing from the second passage to the second passage is stopped.

According to the present invention, the flow rate of the refrigerant can be controlled stepwise by operating the two solenoid valves by the ON / OFF control circuit to which the delay control is added, and the flow noise when the valve is closed from the open state. (Water hammer phenomenon) does not occur.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a composite solenoid valve and a method for controlling the composite solenoid valve according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a composite solenoid valve of the present invention according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The composite solenoid valve of the present invention performs an expansion valve function (controls the flow rate of the refrigerant in a stepwise manner) and an electromagnetic valve function used for air conditioning control on the rear seat side in the vehicle compartment. The composite solenoid valve has one valve body 8 having a first flow passage 2 and a second flow passage 4 and two solenoid valves attached to the valve body 8, that is, a first solenoid valve 18 and a second solenoid valve. Solenoid valve 19
The two solenoid valves are operated by an ON / OFF control circuit to which delay control is added, so that the flow rate of the refrigerant can be controlled in a stepwise manner. Phenomenon) does not occur.

The valve body 8 is connected to the inlet 1 of the high-pressure refrigerant.
Is provided at the outlet of the low-pressure refrigerant in parallel with the first flow passage 2.
Is provided with a second flow passage 4 leading to the second passage. Further, the valve body 8 is provided with chambers 5 and 5a connected to the first flow passage 2, and provided with valve seats 6 and 6a at the bottoms of the chambers 5 and 5a. The valve seat 6 has a large valve port 7 communicating with the first flow passage 2.
However, a small valve port 7a communicating with the second flow passage 4 is provided in the valve seat 6a.

The first solenoid valve 18 is provided on the refrigerant inlet side, and the second solenoid valve 19 is provided on the refrigerant outlet side. These first solenoid valve 18 and second solenoid valve 19 are
Non-magnetic plunger tubes 9 and 9a fixed to the upper surface of the valve body 8 at intervals, and elastic packings 10 and 10a fixed to the plunger tubes 9 and 9a and fixed at lower ends thereof. Children 11 and 11a,
Plungers 14 and 14a which are provided with insertion holes 12 and 12a for the upper coil spring and elastic valve packings 13 and 13a at the lower end thereof and which are slidably inserted in the plunger tubes 9 and 9a vertically. It is constituted by compression coil springs 15 and 15a for urging the plungers 14 and 14a downward, electromagnetic coils 16 and 16a, and a housing 17 made of a magnetic material.

As described above, by arranging the first electromagnetic valve 18 and the second electromagnetic valve 19 side by side, the two electromagnetic coils 16 and 16a can be integrally molded.

The valve packings 13 and 13a
As shown in FIG. 3, a notch 2
1 and 21a, and lateral grooves 22 and 2 on the upper surface.
2a and a plurality of vertical grooves 23 and 23a on the side surface, while vertical holes 20 and 20a are provided in the center of the plungers 14 and 14a side. When introduced into 5 ′, 5a, 5a ′, the vertical holes 20, 20a in the plungers 14, 14a
The chambers 5, 5 'and the chambers 5a, 5a' communicate with each other by the horizontal grooves 22, 22a and the vertical grooves 23, 23 of the valve packings 13, 13a, so that the pressure is always equalized and the force is canceled, and the refrigerant is cooled. The plungers 14, 14 are mixed with the gas so that the refrigerating machine oil does not flow downward so that oil does not accumulate in the chambers 5 ', 5a'.
a can be easily slidable in the vertical direction.

The flow rate of the refrigerant can be controlled stepwise by ON / OFF control of the first solenoid valve 18 and the second solenoid valve 19. That is, when a large amount of refrigerant flows, the first solenoid valve 18 and the second solenoid valve 19 are turned on.
, And the high-pressure refrigerant flows from the inflow port 1 through the first flow path 2 to the chamber 5.
After that, one of them flows from the valve port 7 to the second flow passage 4,
The other is configured to flow out of the first flow passage 2 → the chamber 5 a → the valve port 7 a → the second flow passage 4 from the flow outlet 3.

When a medium flow rate of refrigerant flows, the first solenoid valve 18 is turned on and the second solenoid valve 19 is turned off, the valve port 7 is opened, and the valve port 7a is closed. Flows into the chamber 5 from the inflow port 1 through the first flow path 2, and then flows from the valve port 7 → the second flow path 4 → the outflow port 3.

When a small amount of refrigerant flows, the first solenoid valve 18 is turned off and the second solenoid valve 19 is turned on, the valve port 7 is closed, and the valve port 7a is open. Flows into the chamber 5 from the inflow port 1 through the first flow path 2, and then flows from the first flow path 2 to the outflow port 3.

Next, in order to prevent the water hammer phenomenon when the operation of the rear cooler is stopped, that is, when the flow of the refrigerant to the evaporator is stopped, an ON / OFF control with a delay control of these two solenoid valves is added. Since the operation is performed by the control circuit, a control method thereof will be described below.

FIG. 4 is a graph chart for delay control of two solenoid valves. In FIG. 4, among the input signals, a signal A is a signal for flowing a large flow rate refrigerant, a signal B is a signal for flowing a medium flow rate refrigerant, and a signal C is a signal for flowing a small flow rate refrigerant. The first solenoid valve 18 having a large valve port and the second solenoid valve 19 having a small valve port
To stop the flow of the refrigerant from the open state (a large flow of the refrigerant is flowing) after N, the first solenoid valve 18 is first turned off to close the large valve port 7 and then delayed for several seconds. The second solenoid valve 19 is turned off to close the small valve port 7a to stop the refrigerant flowing from the first passage 2 to the second passage.

In the case of a medium flow, a second valve having a small valve port
The solenoid valve 19 is turned off and the first solenoid valve 18 having a large valve port is turned on to open the valve, and the refrigerant flows through the inlet 1 → the large valve port 7 → the second flow passage 4 → the outlet 3. When the flow of the refrigerant is stopped from the state in which the first electromagnetic valve 18 and the second electromagnetic valve 19 are once turned on, a large flow amount of the refrigerant flows, and then the first electromagnetic valve 18 is turned off. The large valve port 7 is closed, and then the second solenoid valve 19 is turned off with a delay of a few seconds to close the small valve port 7a, and the first passage 2 is closed.
The refrigerant flowing from the second passage to the second passage is stopped.

In the case of a small flow, the first having a large valve port
From the state where the electromagnetic valve 18 is turned off and the second electromagnetic valve 18 having a small valve port is turned on to open the valve, and the refrigerant flows from the inlet port 1 → the first flow path 2 → the small valve port 7a,
When stopping the flow of the refrigerant, the second solenoid valve 19 is turned off to close the small valve port 7a, and the second solenoid valve 19 is closed from the first passage 2 to the second passage.
Stop the refrigerant flowing to the passage.

[0048]

According to the composite solenoid valve of the present invention, the construction is such that two solenoid valves are attached to one valve body having a first flow passage and a second flow passage, and the two solenoid valves are mounted on the valve body. Since the refrigerant flow is controlled in a stepwise manner by operating the ON / OFF control circuit with the delay control of the above, the expansion as the evaporator on the rear side of the car cooler can be achieved with a simple structure and low cost. Can perform functions. Further, according to the control method of the composite solenoid valve of the present invention, since these two solenoid valves are operated by ON / OFF control with delay control added, the solenoid valve is changed from the open state to the valve closing operation. No flow noise (water hammer phenomenon).

[Brief description of the drawings]

FIG. 1 is a plan view of a composite solenoid valve of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an enlarged perspective view of a valve packing according to the present invention.

FIG. 4 is a graph chart for delay control of two solenoid valves.

FIG. 5 is a circuit diagram of a refrigeration cycle to which a conventional solenoid valve-integrated expansion valve is applied.

FIG. 6 is a longitudinal sectional side view of a conventional solenoid valve-integrated expansion valve.

[Explanation of symbols]

1 inlet 2 first passage 3
Outflow port 4 Second flow path 5 Chamber 6 Valve seat 7 Valve port 8 Valve body 9 Plunger tube 10 Packing 11 Suction element 12 Coil spring insertion hole 13 Valve packing 14 Plunger 15 Compression coil spring 16 Electromagnetic coil 17 Housing 18 First solenoid valve 19 Second solenoid valve 20 Vertical hole

Continuation of the front page F term (reference) 3H106 DA07 DA13 DA25 DA32 DB02 DB13 DB24 DB32 DC02 DC17 DD03 EE34 EE37 GA13 GA15 GA26 GB06 GB11 HH05 KK17 KK23

Claims (4)

[Claims] 1. A first flow passage 2 leading to an inlet 1; a second flow passage 4 leading to an outlet 3; chambers 5 and 5a leading to the first flow passage 2; Valve seats 6 and 6a provided at the bottom of 5 and 5a,
A valve body 8 having a large valve port 7 communicating with the first flow path 2 and a small valve port 7a communicating with the second flow path 4; Non-magnetic plunger tubes 9 and 9a fixed thereto, and suction elements 11 and 11a fixed to the plunger tubes 9 and 9a and having elastic packings 10 and 10a fixed to lower ends thereof.
And plungers 14 and 14a, which are provided with insertion holes 12 and 12a for the upper coil spring and elastic valve packings 13 and 13a at the lower end thereof so as to be vertically slidable in the plunger tubes 9 and 9a. The compression coil springs 15 and 15a for urging the plungers 14 and 14a downward, the electromagnetic coils 16 and 16a and the housing 17 made of a magnetic material make the first side of the refrigerant inlet side open.
An electromagnetic valve 18 is provided, and a second electromagnetic valve 19 is provided on the refrigerant outlet side. ON / OFF of the first electromagnetic valve 18 and the second electromagnetic valve 19
A composite solenoid valve characterized in that the flow rate of refrigerant can be controlled stepwise by control. 2. Notches 21 and 21a are provided on the outer peripheral edge of the upper surface of the valve packings 13 and 13a, and lateral grooves 22 and 22a are provided on the upper surface, and a plurality of vertical grooves 23 and 23a are provided on the side surface. The composite solenoid valve according to claim 1, wherein the plungers (14, 14a) are provided with vertical holes (20, 20a) at the center thereof. 3. The first solenoid valve 18 and the second solenoid valve 19 are provided side by side and two electromagnetic coils 16, 16 are provided.
The composite solenoid valve according to claim 1, wherein a is integrally molded. In the compound solenoid valve according to the first aspect, when controlling the flow rate of the refrigerant in a stepwise manner, when the large flow rate of the refrigerant is stopped, (a) the first solenoid valve 18 having a large valve port and the small The fact that the second solenoid valve 19 having the valve port is turned on and in the open state is determined by (b) first turning off the first solenoid valve 18 to close the large valve port 7, and then delaying by a few seconds. (2) When the small valve port 7a is closed by turning off the electromagnetic valve 19 to stop the refrigerant flowing from the first passage 2 to the second path and stop the medium flow rate refrigerant, (c) the small valve port is provided. The second solenoid valve 19 is turned off and the first solenoid valve 18 having a large valve port is turned on to open the valve, and the refrigerant flows into the inlet 1 → the large valve port 7 → the second flow passage 4 → the outlet 3 (D) Once the first solenoid valve 18 and the second solenoid valve 19 are once turned on
(E) Next, the first solenoid valve 18 is turned off to close the large valve port 7, and then the second solenoid valve 19 is turned off after a delay of several seconds to reduce the small flow rate. Valve port 7
When the valve a is closed to stop the refrigerant flowing from the first passage 2 to the second passage and to stop the small amount of refrigerant, (f) the first solenoid valve 18 having a large valve port is turned off and the small valve is turned off. When the second solenoid valve 19 having a port is turned on to open the valve, and the refrigerant flows from the inlet port 1 → the first flow passage 2 → the small valve port 7a, (g) the second solenoid valve 19 A control method for a composite solenoid valve, characterized in that the valve is turned off to close a small valve port (7a) to stop the refrigerant flowing from the first passage (2) to the second passage.