JP3426791B2 - Temperature type automatic expansion valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature type automatic expansion valve used in an air conditioner.

[0002]

2. Description of the Related Art Conventionally, a vehicle such as a wagon is equipped with a desired conditioned air by blowing arbitrary conditioned air to a front seat side of a passenger compartment and a partial area inside the car, for example, a rear seat side. There is known a vehicle air conditioner that is maintained at a temperature.

FIG. 3 shows a conventional refrigeration cycle relating to this type of vehicle air conditioner, and a schematic actual view of an air conditioning system.
4 shows the cross-sectional view of the heater unit in FIG.

In these drawings, reference numeral 18 is a front seat air-conditioning unit installed in the front part of the automobile, which comprises a blower 15, an evaporator 11, a heater 16, an air mix damper 21, and
It is equipped with an outlet switching damper. Reference numeral 19 is a rear seat air conditioning unit installed in the rear part of the automobile, and is provided with a blower 17 and an evaporator 14. The refrigerant discharged from the compressor 12 driven from the engine 24 via the electromagnetic clutch 23 enters the condenser 13 where it radiates heat to be condensed and liquefied, and then branches via the receiver 9. One of the branched liquid refrigerant is adiabatically expanded by the expansion valve 1 via the electromagnetic valve 10 and then enters the evaporator 11, where the air in the vehicle interior 26 sent by the blower 15 or the outside air is cooled to evaporate the air. And returns to the compressor 12.

The other of the branched liquid refrigerant is the solenoid valve 25.
After being adiabatically expanded by the expansion valve 1 via the expansion valve 1, it enters the evaporator 14 where it cools the air in the passenger compartment 26 sent by the blower 17 to evaporate and vaporize the air.
Return to 2.

Evaporator 1 of front seat air conditioning unit 18
The air cooled by 1 is branched by the air mix damper 21, and a part of the air is heated by exchanging heat with the engine cooling water circulating in the heater 16 while flowing through the heater 16. Then, the air is mixed with the rest of the air bypassing the heater 16 to become conditioned air 22 of a predetermined temperature, and is blown out from the air outlet selected by an air outlet switching damper (not shown) to the front portion of the vehicle interior 26 to the front seat side. Air condition.

The air cooled by the evaporator 14 of the rear seat air conditioning unit 19 is blown out to the rear of the passenger compartment 26, and the thermostat 27 installed in the rear seat air conditioning unit controls the solenoid valve 25 to be turned on and off. Then air-condition at a predetermined temperature.

As shown in FIG. 3 , the conventional temperature type automatic expansion valve, that is, the expansion valve 1 is connected to the inlet side of the evaporators 11 and 14, and the outlets of the evaporators 11 and 14 detected by the temperature sensitive cylinder 6 are connected. The throttle amount is automatically controlled by the change of the refrigerant temperature, the refrigerant superheat degree at the outlets of the evaporators 11 and 14 is maintained in an appropriate state, the cooling effect is sufficiently exerted, and the function of preventing the liquid refrigerant from returning to the compressor 12 is provided. There is.

[0009]

The conventional temperature type automatic expansion valve described above has the following problems to be solved.

That is, the conventional automatic expansion valve 1 of the temperature type has only the function of adjusting the superheat degree of the refrigerant at the outlets of the evaporators 11 and 14, and has two or more evaporators 11 and 1.
In a refrigeration cycle in which 4 are connected in parallel, in order to stop the flow of the refrigerant to the evaporator that is not used when each evaporator 11 and 14 is used independently,
Separately, it was necessary to add an opening / closing device such as the solenoid valve 25 in the refrigeration cycle. However, the solenoid valve 25 is replaced by the expansion valve 1
When installed before, when the distance between the solenoid valve 25 and the expansion valve 1 is long, when the solenoid valve 25 is closed, the liquid refrigerant on the downstream side of the solenoid valve 25 flows to the low pressure side via the expansion valve 1. This causes bubbles. There is a problem that abnormal noise is generated when the liquid accompanied by the bubbles passes through the expansion valve 1.

Further, when the solenoid valve 25 is opened, the high-temperature high-pressure liquid refrigerant is rapidly released into the pipe between the solenoid valve 25 and the expansion valve 1 which is at a low pressure by the compressor 12, and an impact sound is generated in the pipe. There was a problem of doing.

An object of the present invention is to provide a temperature type automatic expansion valve and the like which solve the above problems.

[0013]

As a means for solving the above problems, the present invention is to provide a temperature type automatic expansion valve described in (1 ) below and a refrigeration cycle described in ( 2 ) below.

(1) A throttle valve mechanism provided on the evaporator inlet side of the refrigeration cycle for adiabatically expanding the high temperature and high pressure liquid refrigerant from the condenser, a temperature sensitive tube for detecting the refrigerant temperature at the evaporator outlet, and a temperature sensitive tube. Detected refrigerant temperature, comprising a diaphragm mechanism that operates the throttle valve mechanism according to the change in pressure, the temperature of the refrigerant at the evaporator outlet,
In a thermal automatic expansion valve that automatically controls the throttle according to the change in pressure and maintains the refrigerant superheat at the evaporator outlet in an appropriate state, a system path that guides the pressure on the high pressure side of the throttle valve mechanism to the low pressure side chamber of the diaphragm mechanism. The temperature-controlled automatic expansion valve is characterized in that the electromagnetic on-off valve mechanism is incorporated in the same path.

[0015]

( 2 ) In a refrigeration cycle in which a compressor, a condenser, a temperature type automatic expansion valve and an evaporator are connected by a refrigerant pipe, the temperature type automatic expansion valve and the evaporator are connected in parallel in a plurality of lines, and each pipe system is connected. in the refrigeration cycle formed by providing a solenoid valve, in place of the temperature automatic expansion valve and solenoid valve, a refrigeration cycle characterized by using a thermostatic automatic expansion valve of the above (1) Symbol placement.

[0017]

Since the present invention is constructed as described above, it has the following actions.

(1). In the configuration of (1) above, a system path (flow path) for guiding the high pressure side of the throttle mechanism of the temperature type automatic expansion valve to the low pressure side of the diaphragm mechanism is provided, and an electromagnetic opening / closing valve mechanism is incorporated in the system path. With the configuration, when the electromagnetic on-off valve is opened, the high-pressure refrigerant acts on the low-pressure side of the diaphragm through the system path, and the valve rod and valve that are displaced together with the diaphragm close the flow path as the temperature type automatic expansion valve, and the refrigerant is completely discharged. To be shut off.

Therefore, an independent solenoid valve is not required on the upstream side of the temperature type automatic expansion valve as in the conventional case.

Therefore, there is also no space for producing bubbles or impact noise.

[0021]

( 2 ). In the configuration of ( 2 ) above, a plurality of normal temperature type automatic expansion valves and evaporators are connected in parallel, and an electromagnetic opening / closing valve is provided in each piping system. Since the temperature-type automatic expansion valve described in (1 ) above is used instead of the valve, the functions of the conventional temperature-type automatic expansion valve and the electromagnetic on-off valve can be obtained by one temperature-type automatic expansion valve and different from the conventional one. No sound or impact noise is generated.

[0023]

An example of the embodiment of the present invention will be described with reference to FIGS.

The same components as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted unless necessary.

[0025]

FIG. 1 is a vertical cross-sectional view of a temperature type automatic expansion valve according to the present embodiment (hereinafter simply referred to as "expansion valve"), and FIG. 2 is an enlarged view of the vicinity of the coil 8 on the right side of FIG. .

Here, a high-pressure liquid refrigerant flows in from a lower inlet, is throttled by a throttle valve, adiabatically expands, and then flows out from a lateral outlet.

In FIG. 1, the expansion valve 1 has a temperature sensing cylinder 6 for detecting the refrigerant temperature at the evaporator outlet, a diaphragm 5 that moves up and down depending on the pressure balance between the temperature sensing cylinder 6 and the inside of the valve body, and pushes the diaphragm 5 upward. It is composed of a spring 4 acting in the direction of closing the valve 3 and a valve rod 2 connecting the valve 3 and the diaphragm 5. Further, as shown in FIG. 2, a coil 8, a valve 28, a plunger 29, and a spring 30 are provided on the low pressure side of the pipe 7 that connects the high pressure side and the low pressure side below the diaphragm 5, and when the coil 8 is energized. , The plunger 29 and the valve 28 are sucked to the right in the figure, the flow path of the pipe 7 is opened, and the high-pressure refrigerant flows into the low-pressure portion below the diaphragm 5 and pushes the diaphragm 5 upward, whereby the valve rod 2, the valve 3 is also pushed upwards and valve 3
This closes the mainstream flow path. On the other hand, when the coil 8 is not energized, the spring 29 causes the plunger 29 and the valve 28 to move.
Moves to the left, the flow path of the pipe 7 is closed, the inflow of high-pressure refrigerant to the lower portion of the diaphragm 5 is stopped, and only normal expansion valve control is performed.

[0029]

[0030]

[0031]

As described above, according to the present embodiment, when it is desired to shut off the refrigerant passing through the expansion valve 1, when the coil 8 is energized, the valve 28 on the pipe 7 side is opened and the high pressure refrigerant flows under the diaphragm 5. , Valve 5 with diaphragm 5, valve 3
Since the valve 3 closes up the mainstream refrigerant passage, there is an advantage that no special solenoid valve needs to be provided upstream of the expansion valve 1 unlike the conventional case.

Further, since the expansion valve 1 itself has the function of completely shutting off the refrigerant, and does not require a special independent solenoid valve on the upstream side, the solenoid valve between the solenoid valve and the expansion valve which are closed as in the conventional case is provided. The liquid refrigerant flows to the low pressure side through the expansion valve, and there is an advantage that a problem such as making an abnormal noise does not occur when the liquid that has generated bubbles passes through the expansion valve.

Further, since it is not necessary to provide an independent solenoid valve on the upstream side of the expansion valve 1, when the solenoid valve is opened as in the conventional case, a high temperature is generated in the pipe between the solenoid valve and the expansion valve 1. There is an advantage that the problem that the high-pressure liquid refrigerant is suddenly released and an impact sound is generated in the pipe does not occur.

[0035]

[0036]

[0037]

[0038]

Since the present invention is configured as described above, it has the following effects (1) to (3).

(1). According to the expansion valve of the present invention, since the function equivalent to the function of the electromagnetic valve is added to the conventional expansion valve, there is no need to separately prepare an independent electromagnetic valve,
The number of parts can be reduced.

(2). When the flow of the refrigerant is stopped, the refrigerant is stopped by the valve portion provided in the expansion valve, so that the liquid refrigerant accompanied by bubbles does not pass through the expansion valve, and no abnormal noise is generated.

(3). Since an independent solenoid valve is not required upstream of the expansion valve, when the solenoid valve is opened as in the conventional case, high-temperature high-pressure liquid refrigerant is suddenly released between the expansion valve and the solenoid valve, and an impact noise is generated. That problem does not occur.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a temperature type automatic expansion valve according to an embodiment of the present invention,

FIG. 2 is an enlarged view of the right side portion of FIG.

FIG. 3 is a refrigeration cycle diagram of a conventional vehicle air conditioning system,

FIG. 4 is a schematic actual view of a conventional vehicle air conditioning system,

FIG. 5: Heater unit of conventional vehicle air conditioning system
FIG.

[EXPLANATION OF SYMBOLS] 1 expansion valve (thermostatic automatic expansion valve) 2 stem 3 valve 4 spring 5 Diaphragm 6 temperature sensing tube 7 pipe 8 coil 11 the evaporator 12 compressor 13 condenser 14 evaporator 28 valve 29 plunger 30 sprint grayed

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F25B 41/06 F25B 41/00 B60H 1/32

Claims (2)

(57) [Claims] 1. A throttle valve mechanism provided on the evaporator inlet side of a refrigeration cycle for adiabatically expanding high-temperature and high-pressure liquid refrigerant from a condenser, a temperature-sensitive tube for detecting the refrigerant temperature at the evaporator outlet, and a temperature-sensitive tube for detection. Equipped with a diaphragm mechanism that operates the throttle valve mechanism in response to changes in the temperature and pressure of the refrigerant, and automatically controls the throttle in accordance with changes in the temperature and pressure of the refrigerant at the evaporator outlet, to optimize the degree of refrigerant superheat at the evaporator outlet. In the temperature type automatic expansion valve that keeps
A temperature type automatic expansion valve, characterized in that a system passage for guiding the pressure on the high pressure side of the throttle valve mechanism to the low pressure side chamber of the diaphragm mechanism is provided, and an electromagnetic on-off valve mechanism is incorporated in the system passage. 2. A compressor, a condenser, a temperature type automatic expansion valve.
And a refrigeration cycle consisting of an evaporator connected by a refrigerant pipe.
The temperature-controlled automatic expansion valve and evaporator.
Several systems are connected in parallel and an electromagnetic on-off valve is installed in each piping system.
In the provided refrigeration cycle, the temperature-based automatic expansion
The temperature type automatic valve according to claim 1, instead of the valve and the solenoid opening / closing valve.
A refrigeration cycle comprising a dynamic expansion valve.