JPS5930281Y2 - pressure regulating valve - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pilot-type pressure regulating valve that maintains constant evaporation pressure in a refrigeration cycle.

This type of pressure regulating valve uses a pilot valve to open and close the pilot hole according to the temperature of the refrigerant flowing out of the evaporator, and this opening and closing controls the refrigerant communication by interlocking with the main valve to maintain a constant evaporation pressure. It is supposed to be done.

That is, in Fig. 3, a is a pilot hole, b is a sensing part provided above the pilot hole a, the inside of the sensing part is partitioned by a diaphragm C, and the upper chamber d is filled with gas at a constant pressure. Further, a pressure equalizing hole f is formed in the wall surface of the lower chamber e.

A double rotor valve g is attached to the center of the diaphragm C.

When the evaporation pressure is maintained at a predetermined value, the pressure and the pressure in the upper chamber d are balanced, and the pilot valve g is separated from the pilot hole a, that is, the pilot hole a is in an open state. .

When the evaporation pressure decreases below a predetermined value from this state, the pressure in the lower chamber e also decreases through the pressure equalization hole f, and accordingly, the pilot valve g descends and the pilot hole a is closed, and with this closing, the main valve (not shown) moves in the valve closing direction.

However, such a conventional configuration (Japanese Unexamined Patent Publication No. 53-73
No. 645), even when the pilot valve g is lowered, the pilot hole a remains open at the beginning, and it is only when the tip of the pilot valve g comes into contact with the inner peripheral edge of the pilot hole a that the actual state of the pilot hole a is opened. Closure is what is achieved.

That is, the actual closing of the pilot hole a is delayed in time from the drop in evaporation pressure, resulting in a disadvantage that responsiveness is lacking.

If the pilot valve g is placed close to the pilot hole a, the response can be improved that much. However, if the pilot valve g is placed close to the pilot hole a, the pilot valve g will be damaged due to vibration etc.
Therefore, it is necessary to keep the pilot valve g apart from the pilot hole a by a certain amount or more.

The present invention was developed with attention to these points, and its purpose is to provide a pressure regulating valve with excellent responsiveness that can immediately recover the evaporation pressure when it decreases. There is a particular thing.

That is, the present invention includes a main body having an inlet communicating with the outlet side of the evaporator and an outlet communicating with the suction side of the compressor;
The main body is divided into an inlet side and an outlet side, and a bottomed cylindrical holding cylinder has a communication port on one circumferential surface that communicates between the two, and the holding cylinder is slidably housed inside the holding cylinder. a main valve that opens and closes the communication port by its sliding displacement; and a spring that elastically biases the main valve to normally open the communication port.

A pilot chamber is formed between the holding cylinder and the end wall of the main valve and communicates with the inlet side of the main body via the pilot hole and the outlet side of the main body via the orifice, and the pilot hole is normally closed. It is equipped with a pilot valve and a heat-sensitive response mechanism provided facing the inlet side of the main body and interlocking the pilot valve.

The heat-sensitive response mechanism is characterized in that it senses a decrease in the temperature of the refrigerant, and opens the normally closed pilot valve based on the sensing.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 and 2.

In the figure, 1 is the main body, which has an inlet 2 that communicates with the outlet side of the evaporator at one end, and an outlet 3 that communicates with the suction side of the compressor at the other end.
have.

A cylindrical holding cylinder 4 with a bottom is provided inside the main body 1.

The holding cylinder 4 divides the inside of the main body 1 into an inlet 2 side and an outlet 3 side.

The holding cylinder 4 has its opening facing the outflow port 3 and slidably accommodates a main valve 5 therein, and the main valve 5 is elastically biased toward the depth of the holding cylinder 4 by a spring 6. has been done.

There are a plurality of communicating lowers on the surface of the holding cylinder 4, and an opening/closing opening 8 corresponding to the communicating lowers on the peripheral surface of the main valve 5.
. . . are respectively formed, and the communicating lowers . . . are opened and closed via the opening/closing ports 8 .

Further, a pilot chamber 9 is formed between the inner surface of the end wall of the holding cylinder 4 and the outer surface of the end wall of the main valve 5, and this pilot chamber 9 is always connected to the main valve body by an orifice 10 bored in the end wall of the main valve 5. It communicates with the outlet 3 side of 1.

A heat sensitive response mechanism 11 is provided on the outer surface of the end wall of the holding cylinder 4,
This is formed by partitioning the inside of a flat shell 12 with a diaphragm 13, with one chamber serving as an expansion/contraction chamber 12a and the other chamber serving as an inflow chamber 12b.

The inflow chamber 12b communicates with the inlet 2 side of the main body 1 through a through hole 14 bored in the shell 1''2K, and
It communicates with the pilot chamber 9 through a relatively large pilot hole 16 formed in the end wall of the holding cylinder 4, and a pilot valve 15 is attached to the diaphragm 13 in correspondence with the pilot hole 16. .

The expansion chamber 12a is filled with condensable gas, and the pressure of this gas presses the pilot valve 15 through the diaphragm 13 during normal times, that is, when the evaporation pressure is maintained at a predetermined pressure. Pilot hole 16
is closed.

With the pressure regulating valve configured in this way, when the evaporation pressure of the evaporator is acting on the inlet 2 at a predetermined pressure, the pilot chamber 9 is maintained at a low pressure by the suction force of the compressor. As shown in FIG. 1, the main valve 5 is held in the upper part by the urging force of the spring 6, so that the opening/closing port 8 faces the communication lower part, and the refrigerant is sequentially supplied from the inlet port 2 to the communication lower part. . . . flows to the outflow port 3 via the opening/closing port 8 .

When the evaporation pressure of the refrigerant falls below a predetermined value in such a state, the temperature of the refrigerant also falls, and this temperature change is transmitted to the condensable gas in the expansion/contraction chamber 12a.

Then, the gas condenses and the pressure inside the expansion and contraction chamber 12a decreases, and the diaphragm 13 is displaced and the pressure inside the expansion and contraction chamber 12a decreases.
a contracts, the pilot valve 15 is displaced upward, and the pilot hole 16 is opened.

Due to this opening, the inflow chamber 12b and the pilot chamber 9 communicate with each other, and the refrigerant on the inlet 2 side flows into the pilot chamber 9 through the through hole 14 and the pilot hole 16 in order, and the pressure in the pilot chamber 9 increases. The main valve 5 is pushed down against the spring 6 due to the upward movement, and the communication port I is closed by the peripheral wall of the main valve 5, thereby preventing the flow of the refrigerant.

As a result, the pressure of the refrigerant recovers to the predetermined value, and after this recovery, the temperature of the refrigerant also recovers to the current temperature, which is sensed by the condensable gas, so each member returns to its original position and the refrigerant flows to the inlet. 2 to the outlet 3.

However, by repeating such operations, the evaporation pressure is maintained at a constant value.

In the above embodiment, the expansion/contraction chamber is constructed using a diaphragm, but it may also be constructed using a bellows or the like.

As explained above, according to the present invention, the pilot hole is normally closed by the pilot valve, and when the evaporation pressure decreases, the normally closed pilot valve rises and the pilot hole is opened. The main valve moves in the valve closing direction, and therefore, the pilot hole is opened at the same time as the pilot valve starts operating.

In other words, the pilot hole is sensitively opened at the same time as the evaporation pressure drops, without the time delay that is conventional.
It is possible to immediately move the main valve in the valve closing direction, and therefore the response is improved and the evaporation pressure can be quickly recovered.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of an embodiment of the present invention before operation;
The same figure is a cross-sectional view after operation, and FIG. 3 is a cross-sectional view showing a conventional pressure regulating valve. 1. Main body, 2. Inlet, 3. Outlet, 4.
・・Holding tube, 5・・Main valve, 6・・Spring, T・
- Series of ports, 9... Pilot chamber, 10... Orifice, 11... Heat sensitive response mechanism, 15... Pilot valve, 16... Pilot hole.

Claims (1)

[Scope of utility model registration request] A main body has an inlet communicating with the outlet side of the evaporator and an outlet communicating with the suction side of the compressor, and the main body is divided into an inlet side and an outlet side, and a circular shape is formed between the two. a bottomed cylindrical holding cylinder having a communication port for communicating with the main valve; A spring is formed between the retaining cylinder and the end wall of the main valve, and the spring is biased to normally open the communication port. a pilot chamber that communicates with each other, a pilot valve that normally closes the pilot hole, and a thermally responsive mechanism that communicates with the pilot valve that is provided facing the inlet side of the main body, and the thermally responsive mechanism that communicates with the refrigerant. A pressure regulating valve is characterized in that it senses a temperature drop in the air and opens the normally closed pilot valve upon sensing the temperature drop.