JPH0356392B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigeration system with a reduced restart load, and more specifically to a refrigeration system in which a circuit is closed to prevent condensed refrigerant from flowing into an evaporator when the compressor is stopped.
It also relates to improvements in differential pressure on/off valves that operate quickly.

When the compressor is stopped, the refrigerant pressure difference before and after the compressor is balanced, but the high pressure of the condensed refrigerant in the condenser is maintained while blocking the flow to the evaporator, reducing the restart load and improving power efficiency. is planned.

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 it has often been pointed out that the solenoid valve attracts noise depending on the location of the refrigerator.

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

FIG. 1 shows an example of a refrigeration system using such a differential pressure on/off valve, with rotary compressor A, condenser B,
Capillary tube C evaporator D is sequentially connected by conduit E, and a differential pressure on/off valve _V1 is interposed between condenser B and capillary tube C, and between evaporator D and rotary compressor A. A check valve V ₂ is interposed, and a pressure introduction pipe F 1 is installed 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 F ₁ is installed between the suction side of the rotary compressor A after the check valve V ₂ and the A pressure introduction pipe _F2 is connected between the outlet side of the evaporator D and the differential pressure on/off valve _V1 , respectively.

In the differential pressure on/off valve V ₁ , the primary port 2 is connected to the valve body 1.
and a secondary port 3 are formed, and a ball valve 5 approaches and separates from the valve seat 4 between them. A diaphragm 8 is provided at the bottom of the valve body 1 with its peripheral edge supported by a lid 6 and a lid 7, and a pressure introduction pipe is connected to the pressure chamber in the lid 6.
F ₁ is communicating. 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 inserted through a packing housing 11 provided between the valve body 1 and
It is sealed with a seal seal 10. A seal presser 12 is provided for the seal seal 10, which is pressed by a leaf spring 13. diaphragm 8
A pressure introduction pipe _F2 communicates with the pressure chamber in the upper lid 7. Primary port 2 has a pipe line from condenser B.
E ₁ is connected to the secondary port 3, 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 to the diaphragm. A high pressure condition is introduced below the diaphragm 8.
The ball valve 5 is pushed up against the valve seat 4 against the pressure generated by the upper low pressure state and the spring 15, thereby cutting off the refrigerant and blocking the inflow into the capillary tube C.

By the way, in this structure, the differential pressure on-off valve and the check valve are separate, and two pressure introduction pipes must be drawn from the front and back of the check valve to the pressure on-off valve and connected. There is a problem that the process becomes complicated and piping work such as brazing takes time.

The present invention has been made with attention to the above-mentioned points, and a check valve is integrated into a differential pressure on/off valve.

FIG. 2 shows an embodiment of the present invention, in which a rotary compressor A, a condenser B, a capillary tube c as a pressure reducing mechanism, an evaporator D, and a differential pressure shut-off valve V ₁ ' are connected by a conduit E. .

That is, the differential pressure on/off valve V ₁ ′ is located in the valve body 20,
It has a first inlet 20a, a first outlet 20b, a second inlet 20c, and a second outlet 20d,
The first inlet 20a is connected to the outlet of the condenser B via line _E1 , the first outlet 20b is connected to the inlet of the capillary tube C via line _E2 , and the second inlet 20c is connected to the outlet of condenser B via 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 .

A valve seat 21a is provided in the valve chamber 21 between the first inlet 20a and the first outlet 20b.
A ball valve 22 that approaches and separates from 1a 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. The presser foot 24 is attached to the packing housing 25
is slidably engaged with.

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 in the middle of a passage that opens into both pressure chambers R ₁ and R ₂ . The stop valve body 29 extends in the pressure chamber _R1 direction and has a sliding cylinder portion 29b relative to the valve body 20.

Check valve main body 29 fixed to diaphragm 28
An interlocking rod 31 is provided between the ball valve 22 and the ball valve 22 . 32 is a seal packing, which is pressed against the packing housing 25 by a spring 33. 34 is Batsuki Bolt.

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.

Next, when the rotary compressor A stops, the refrigerant flows backward, closing the check valve _V2 , and the pressure in the pressure chamber _R2 rises, becoming greater than the sum of the pressure in the pressure chamber _R1 and the force of the spring 23. When the diaphragm 28 is pushed down, the ball valve 22 is closed via the interlocking rod 31, preventing hot refrigerant gas from flowing into the cooler and maintaining the pressure difference.

As explained above, in the present invention, since the check valve is provided inside the differential pressure on/off valve of the refrigeration circuit, the number of brazed parts is reduced, the circuit is simplified, and the response due to the differential pressure is quick. It is.

In particular, in the present invention, since a check valve is provided on the diaphragm that partitions the pressure chamber, the structure can be simplified and manufacturing is easy.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a conventional example, and FIG. 2 is an explanatory diagram showing an embodiment of the present invention. V ₁ ′... Differential pressure on/off valve, 20... Valve body, 20a
...First entrance, 20b...First exit, 20c
...Second entrance, 20d...Second exit, 22...
... Valve body, 23 ... Spring, 28 ... Diaphragm, 31 ... Interlocking rod, V ₂ ' ... Check valve.

Claims (1)

[Claims] 1. A first inlet 20a connected to the condenser, which is a differential pressure on-off valve connected to the pipeline and which works to prevent the high-pressure refrigerant from diffusing into the low-pressure part when the refrigeration cycle is stopped. A valve body 22 biased in the valve opening direction by a spring 23 is provided in the valve chamber 21 between the first outlet 20b and the first outlet 20b connected to the pressure reducing mechanism to open and close the passage between the two ports, and is connected to the evaporator. A second inlet 20c connected to the compressor
A diaphragm 28 is provided between the outlet 20d to partition the pressure chambers R ₁ and R ₂ , and a check valve main body 29 that communicates with both pressure chambers R ₁ and R ₂ is fixed to the diaphragm 28 and is fixed to the check valve main body 29 . Valve body 3 that approaches and separates from valve seat 29a
0 to constitute the check valve V ₂ ', and the diaphragm 2
An interlocking rod 31 is provided between the valve body 22 and the check valve.
The differential pressure is characterized in that the diaphragm 28 closes the valve body 22 against the spring 23 via the interlocking rod 31 due to the differential pressure generated between the pressure chambers R ₁ and R ₂ when V _{2 '} is closed. Open/close valve.