JPH0214621B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a differential pressure on-off valve that closes a circuit to prevent condensed refrigerant from flowing into an evaporator when a compressor is stopped in a refrigeration system.

In a refrigeration system, when the compressor is stopped, the difference in refrigerant pressure before and after the compressor is balanced, but the high pressure in a certain area of the circuit is maintained by maintaining the high pressure of the condensed refrigerant in the condenser and blocking the flow to the evaporator. By reducing the restart load while maintaining the power efficiency, power efficiency is improved.

Conventionally, for this purpose, a solenoid valve is provided between the condenser and the capillary tube, and the solenoid valve is operated by a compressor operation signal so that the valve is opened when the compressor is in operation and closed when the compressor is stopped. However, in refrigerators that are used for a long time, it is desirable to eliminate the solenoid valve even if its power consumption is small, and depending on the location where the refrigerator is installed, the problem of the solenoid valve's suction noise has often been pointed out.

Therefore, in recent years, a technique has been developed that uses a differential pressure on-off valve instead of a solenoid valve.

FIG. 3 shows an example of a refrigeration system using such a differential pressure on/off valve, with rotary compressor A, condenser B,
Capillary tube C and evaporator D are sequentially connected by pipe E, and condenser B and capillary tube C
A differential pressure on/off valve _V1 is interposed between the evaporator D and the evaporator D.
A check valve V ₂ is interposed between the check valve V 2 and the rotary compressor A, and a pressure introduction pipe F ₁ is provided between the suction side of the rotary compressor A after the check valve V ₂ and the differential pressure on/off valve V ₁ , and A pressure introduction pipe F2 is connected between the outlet side of the evaporator D in front of the check valve _V2 and the differential pressure on/off valve _{V1 ,} respectively.

In the differential pressure on/off valve _V1 , a primary port 2 and a secondary port 3 are formed in the valve chamber S of the valve body 1, and a ball valve 5 approaches and separates from a valve seat 4 between them. A diaphragm 8 is provided at the lower part of the valve body 1 with its peripheral edge supported by a lid 6 and a lid 7, and a pressure introduction pipe _F1 communicates with a pressure chamber within the lid 6. A valve rod 9 is in contact with the upper side of the diaphragm 8 via a stopper 16, and a spring 15 is provided between the valve rod 9 and the valve body 1. In the illustrated example, a spring retainer 14 attached to the upper end of the valve stem 9 locks a spring 15 and holds the ball valve 5. The valve stem 9 is the valve body 1
It is inserted through a packing housing 11 provided between the two and sealed with a sealing packing 10.
A seal presser 12 is provided for the seal seal 10, which is pressed by a leaf spring 13. A pressure introduction pipe is installed in the pressure chamber inside the lid 7 above the diaphragm 8.
F ₂ is communicating. A conduit E ₁ from the condenser B is connected to the primary port 2, and a conduit E ₂ to the capillary tube C is connected to the secondary port 3.

In the above configuration, while the rotary compressor A is in operation, the pressures before and after the check valve V ₂ are in a low pressure state that is almost equal, and these are introduced to both sides of the diaphragm 8 by the pressure introduction pipes F ₁ and F ₂ and the spring 15 Due to this, the ball valve 5 is connected to the valve seat 4.
The refrigerant leaves the capillary tube C.

Next, when the rotary compressor A is stopped, the high pressure on the discharge side leaks to the suction side, so the pressure rises on the suction side, but since it is blocked by the check valve _V2 , it is passed through the pressure introduction pipe _F1. A high pressure state is introduced below the diaphragm 8, and the ball valve 5 is pushed up against the valve seat 4 against the low pressure state above the diaphragm 8 and the pressure from the spring 15, cutting off the refrigerant and flowing into the capillary tube C. is occluded.

By the way, in this structure, when transmitting the operation of the diaphragm, which is a pressure-responsive member, to the valve body via the valve stem, the valve stem is slid into a sealing member provided between the valve chamber and the pressure-responsive member. Therefore, the sliding resistance of the valve stem is large, and it is difficult to quickly grasp the differential pressure and operate the valve body with a small differential pressure.

The present invention has been made with attention to the above-mentioned points, and in opening and closing differential valve pressure by transmitting the operation of the pressure-responsive member to the valve body via the valve stem, there is By developing a structure that does not provide a sealing member for the valve stem, it is possible to operate the valve body with a small differential pressure.

FIG. 1 shows an embodiment of the present invention, including a rotary compressor A, a condenser B, a capillary tube C,
The evaporator D and the differential pressure on/off valve V ₁ ' are connected by a conduit E.

In other words, the differential pressure on/off valve V ₁ ′ is in the valve body 20,
It has a first inlet 20a, a first outlet 20b, a second inlet 20c, and a second outlet 20d,
A first inlet 20a connects to the outlet of condenser B via line _E1 , a first outlet _20b connects to the inlet of capillary tube C via line E2, and a second inlet 20c connects to line _E3. through the outlet of the evaporator D, and the second
The outlets 20d of are respectively connected to the inlets of the rotary compressor A via conduits _E4 .

The valve chamber 21 between the first inlet 20a and the first outlet 20b is provided with a valve seat 21a on the first inlet 20a side, and a ball valve 2 that approaches and separates from the valve seat 21a.
2 is provided. The ball valve 22 is held by a retainer 24 of a spring 23 provided between the ball valve 22 and the valve body 20, and is urged by the spring 23 in a direction away from the valve seat 21.

On the other side of the valve body 20, an upper lid 26 and a lower lid 27
A metal diaphragm 28 is provided with its peripheral edge supported, and a pressure chamber R ₁ and a pressure chamber R ₂ are formed on both sides of the diaphragm 28, and the second inlet 20c communicates with the pressure chamber R ₁ . and second exit 2
0d communicates with the pressure chamber _R2 .

A check valve V ₂ ' is fixed to the diaphragm 28 through a center hole 28a by ring projection welding. The check valve main body 29 is located in the pressure chamber R ₂ and has a valve body 30 that comes into contact with and separates from a valve seat 29 a provided at the end of a passage that opens into both pressure chambers R ₁ and R ₂ . The check valve main body 29 extends in the pressure chamber _R1 direction and has an engaging cylinder portion 29b. A stopper 29' for the diaphragm 28 engages with the engagement cylinder portion 29b.

A valve rod 31 is provided between the ball valve 22 and the stop 29' that abuts the diaphragm 28. 3
Reference numeral 2 denotes a partitioning member provided between the valve chamber 21 and the diaphragm 28 as a pressure responsive member, and a guide hole 32a for the valve stem 31 is formed in the center.
A valve seat 21b is formed at the end portion a facing the valve chamber 21, facing the valve seat 21a. The partition member 32 is fixed with bolts 33. Note that the presser foot 24 of the spring 23 described above moves while being guided by the outer periphery of the partitioning member.

In the above configuration, when the rotary compressor A is in operation, the pressure chambers R ₁ and R ₂ are at almost the same pressure, so the ball valve 22 is opened by the force of the spring 23, and the refrigerant flows as shown by the arrow. flows.

At this time, the ball valve 22 comes into contact with the valve seat 21b to prevent high pressure from leaking to the low pressure side from the gap between the guide hole 32a and the valve stem 31 (FIG. 2B).

Next, when the rotary compressor A stops, the refrigerant flows backward, which closes the check valve V ₂ ', and the pressure in the pressure chamber R ₂ rises, becoming greater than the sum of the pressure in the pressure chamber R ₁ and the force of the spring 23. When the temperature rises, pushing down the diaphragm 28 moves the ball valve 22 via the valve stem 31 to close the valve seat 21a (Fig. 2A), preventing high-temperature refrigerant gas from flowing into the cooler and reducing the pressure. Maintain the difference.

When the valve is closed, the ball valve 22 is
1b, but since the valve is closed without introducing high pressure into the valve chamber by contacting the valve seat on the inlet side to the valve chamber, there is no problem with respect to leakage.

As explained above, in the present invention, a partitioning member is provided between the pressure-responsive member and the valve chamber, and the operation of the pressure-responsive member is transmitted to the valve body via the valve stem provided in the guide hole of the partitioning member. When the valve body is closed, the valve body is driven by the pressure-responsive member and comes into contact with the valve seat provided at the inlet side of the valve chamber, and when the valve body is opened, the valve body is driven by the spring and is brought into contact with the valve seat provided at the end of the guide hole. Since it is in contact with the valve seat, it is possible to prevent refrigerant leakage while greatly reducing the sliding resistance of the valve stem compared to conventional valve stems. The pressure valve can be activated quickly.

[Brief explanation of drawings]

FIG. 1 is an explanatory cross-sectional view of a main part of an embodiment of the present invention, FIGS. 2A and 2B are enlarged cross-sectional views showing the operation of a ball valve, and FIG. 3 is an explanatory view of a conventional example. V ₁ ′... Differential pressure on/off valve, 20... Valve body, 20a
...Inlet, 20b...Outlet, 21...Valve chamber, 21
a, 21b...Valve seat, 22...Valve body, 23...Spring, 28...Pressure responsive member (diaphragm), 31...Valve rod, 32...Dividing member, 32a
...Guidance hole.

Claims (1)

[Claims] 1 A differential pressure opening/closing valve connected to a pipeline that functions to prevent high-pressure refrigerant from diffusing to a low-pressure section when the refrigeration cycle is stopped, and is defined between the pressure-responsive member 28 and the valve chamber 21. A member 32 is provided and the operation of the pressure responsive member is transmitted to the valve body 22 via a valve stem 31 provided in a guide hole 32a of the partitioning member,
When the valve body is closed, the valve body is driven by the pressure responsive member and comes into contact with the valve seat 21a provided on the inlet side of the valve chamber 21, and when the valve body is opened, the valve body is moved into the guide hole by the spring 23. A differential pressure on/off valve characterized in that it comes into contact with a valve seat 21b provided at an end of the valve.