JPS6325258B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid control valve for a refrigeration system using a high-pressure container-type hermetic compressor.

In small refrigeration equipment that uses a high-pressure container-type hermetic compressor (hereinafter referred to as a rotary compressor) like a general rotary compressor, the inside of the closed container is on the high pressure side, so the pressure is low like a general reciprocating compressor. Compared to a container-type hermetic compressor (hereinafter referred to as a reciprocating compressor), the amount of refrigerant sealed in the refrigeration system is significantly increased. As an example, in popular refrigerator-freezers, reciprocating type refrigerant fills approximately 150g, while rotary type refrigerant fills approximately 250g.
g, which is a large increase of more than 50%. Of this 100g increase in refrigerant, part is converted into high-temperature, high-pressure superheat gas, and part is dissolved in the refrigerating machine oil and remains in the sealed container. These high-temperature, high-pressure refrigerants are in a gas state when the refrigeration equipment is stopped due to the action of the temperature regulator of the refrigeration equipment, and those dissolved in the refrigeration oil are vaporized and heated in the high-temperature part of the sealed container. The gas becomes a high-temperature, high-pressure superheat gas and flows into the evaporator. As the first flow path, it flows from the closed container to the condenser to the capillary reach tube to the evaporator, and as the heat is radiated by the condenser, it flows as superheated gas at room temperature, but the temperature difference with the evaporator is very large, so the evaporator The disadvantage was that it heated the air, creating a large heat load. In addition, as a second flow path, the high-temperature, high-pressure superheat gas flows as it is from the closed container to the cylinder chamber of the compression element to the suction line to the evaporator, heating the evaporator, which also has the disadvantage of causing a large heat load. The high-temperature, high-pressure gas in the closed container flows into the cylinder chamber because the cylinder chamber of existing rotary compressors is constructed with a mechanical seal made of metal surface contact.
That is, in the refrigeration system using this rotary compressor, a large amount of high-temperature, high-pressure superheat gas flows into the evaporator, resulting in a large heat load. Therefore, even when a rotary compressor, which is about 20% more efficient than a conventional reciprocating compressor, is actually attached to a refrigerator-freezer and measured in the JIS C 9607 power consumption test for electric refrigerators and electric freezers, the effect is still large. The amount of electricity saved was only about 5%. In order to increase the amount of reduction in power consumption equivalent to the efficiency improvement of the rotary compressor,
The purpose is to prevent a large amount of superheat gas from flowing into the evaporator from the first and second flow paths. Currently, some methods are used to improve the second flow path, such as providing a check valve in the suction line of the refrigeration system or providing a check valve inside the rotary compressor. Since the first channel has not been improved, the effect is small, and the reduction in power consumption is only about 5%, for a total effect of about 10%. Further, possible methods for improving the first flow path include:
There is a method of installing a solenoid valve at the condenser outlet and opening and closing it in conjunction with the operation of the refrigeration equipment, but solenoid valves are expensive, generate noise during operation, and require a control circuit for this solenoid valve, making the electrical circuit complicated. Therefore, it had its own drawbacks such as consuming electricity.

In view of the above drawbacks, the present invention is an energy-saving refrigeration system that is inexpensive, does not require electrical control, is quiet, and has an efficiency equal to or higher than that of a rotary compressor alone. The present invention aims to provide a fluid control valve for a refrigeration system.

An embodiment of the present invention will be described below. 1
The rotary compressor is composed of a closed container 2, a compression element 3, and an electric element (not shown).
Furthermore, this rotary compressor 1 is not equipped with a check valve inside. The refrigeration system includes a rotary compressor 1, a condenser 4, a first valve device 5a of a fluid control valve 5 for a refrigeration system of the present invention (hereinafter simply referred to as a fluid control valve), a capillary reach tube 6, an evaporator 7, the fluid The second valve device 5b of the control valve 5, the suction line 8, and the rotary compressor 1 are sequentially connected in an annular manner. The fluid control valve 5 includes a first valve device 5a located above, interposed on the high pressure circuit A side, and a second valve device 5b located below, interposed on the low pressure circuit B side, which are arranged substantially vertically. are doing. Further, the fluid control valve 5 forms an outer shell 11 with a high-pressure side casing 9 having a substantially hollow cylindrical shape and a low-pressure side casing 10 also having a substantially hollow cylindrical shape, and both 9 and 10 are integrated to maintain airtightness. 12 partitions the outer shell 11 into a first valve device 5a and a second valve device 5b;
This is a diaphragm (hereinafter referred to as a pressure responsive element) that moves up and down in response to the pressure of the elevation circuits A and B.

A coil spring 13 is provided at the center of the lower surface of the pressure-responsive element 12 for biasing the pressure-responsive element 12 upward in the figure. 14 is a retainer that holds the lower end of the coil spring 13, and the pressure responsive element 1
2 to restrict excessive movement and prevent damage. This retainer 14 is provided with a plurality of small holes 14a, 14a, . . . for forming refrigerant flow paths. This retainer 14 also includes a valve seat body 10 which will be described later.
c is integrally press-fitted and fixed. Next, the above-described first valve device 5a and second valve device 5b will be explained. The high-pressure side casing 9 has an inlet pipe 9a, an outlet pipe 9b, and a valve seat body 9c of the high-pressure circuit A, and the valve seat body 9c and a high-pressure valve 16, which will be described later, form a first valve device 5a as a high-pressure valve device. It is something that forms.
Specifically, a through hole 12a is provided approximately in the center of the pressure responsive element 12 as shown in FIG.
A protrusion 15a of the holder (hereinafter referred to as a holder) is inserted and sealed, and a high pressure valve 16 made of a ball valve is placed in a recess 15b with a flat bottom formed at the center of the upper end of the holder 15, with a slight gap 15c between the holder 15 and the holder 15. It is held by caulking so that it can be moved slightly. In other words, the gap 15c serves to align the high pressure valve 16 with respect to the valve seat body 9c. The low pressure side casing 10 also has an inlet pipe 10a, an outlet pipe 10b, and a valve seat body 10c, and this valve seat body 10c and a low pressure valve 18, which will be described later, form a second valve device 5b as a low pressure side valve device. It is something to do. More specifically, a low pressure valve 18, which is a leaf valve, is movably housed approximately in the center of the valve seat body 10c, the outer edge of which is provided with a notch 18a that forms a gas passage. Further, above the low pressure valve 18, a retainer 14 for restricting excessive movement of the low pressure valve 18 and holding the coil spring 13 is press-fitted into the valve seat body 10c. The low pressure side casing 10 and the valve seat body 10c are fixed with a screw 10d formed on the valve seat body 10c as shown in FIG. It is sealed and kept airtight.

Next, the operation when the fluid control valve 5 is incorporated into a refrigeration system will be described. FIG. 1 shows a state diagram when the refrigeration system is in operation. The high pressure side of the refrigeration system is at normal high pressure, and the low pressure side is also at normal low pressure, so the pressure responsive element 12 of the fluid control valve 5 The coil spring 13 is pushed down by the pressure difference between the high voltage circuit A and the low voltage circuit B, and is deformed until it hits the retainer 14. Therefore, in the high pressure valve 16, the force due to the pressure difference between the high pressure circuit A and the low pressure circuit B communicating with the evaporator 7 is applied to the valve seat body 9c by the holder 15 integrally attached to the pressure responsive element 12, and the biasing force of the coil spring 13 is applied to the high pressure valve 16. The first valve device 5a overcomes the
is in an open state. On the other hand, the second valve device 5
The low pressure valve 18 of b is blown up by the gas flow flowing in from the evaporator 7 and separated from the valve seat body 10c.
It contacts the retainer 14. The gas flows without any hindrance from the gap between the notch 18a on the outer edge of the low pressure valve 18 and the retainer 14 as shown by the arrow a in FIG.
The valve device 5b is in an open state. Therefore,
The refrigerant gas discharged from the rotary compressor 1 is transferred to the condenser 4, the first valve device 5a of the fluid control valve 5, the capillary reach tube 6, the evaporator 7, the second valve device 5b of the fluid control valve 5, and the suction line 8. , flows to the rotary compressor 1 without any hindrance and performs the refrigeration action.

Next, the state in which the refrigeration system is stopped will be explained using FIG. 2. Since the gas flow from the evaporator 7 is stopped due to the stop of the rotary compressor 1, the low pressure valve 18 of the second valve device 5b of the fluid control valve 5 falls under its own weight and comes into contact with the valve seat body 10c, causing the second
The valve device 5b is closed. As a result, the superheat gas from the rotary compressor 1 is prevented from flowing back into the evaporator 7. As time further passes, the superheated gas in the closed container 2 flows into the cylinder chamber (not shown) of the compression element 3, further into the suction line 8, and into the low pressure side casing 10 of the fluid control valve 5 ( ), so the casing 1
The pressure inside the high pressure side casing 9 rises rapidly and the pressure inside the high pressure side casing 9
The pressure within is approximated. Both casings 9, 1
When the pressure within 0 becomes approximate, the biasing force of the coil spring 13 provided below the pressure-responsive element 12 is applied to the pressure-responsive element 12 due to the pressure difference within both casings 9 and 10.
The holder 15 is pushed up by overcoming the force generated, and the first valve device 5a is closed, thereby preventing superheat gas from flowing into the evaporator 7 from the condenser 4.

Furthermore, the action of the coil spring 13 that urges the pressure responsive element 12 upward will be explained using the pressure change diagram of the refrigeration system shown in FIG. In the figure, the second valve device 5b is closed at the same time as the rotary compressor 1 stops, and the pressure in the suction line 8 of the low pressure circuit B rapidly increases due to the superheat gas flowing back from the rotary compressor 1. At this time, the first valve device 5a is still in an open state, and the pressures in the capacitor 4 and the high-pressure circuit A gradually drop to be equal. When a minute time t has elapsed after this stop, the differential pressure ΔP between the inside of the high pressure side casing 9 and the inside of the low pressure side casing 10 acts on the pressure responsive element 12.
The force F _P (F _P =ΔP×S) generated by the effective area S of the pressure responsive element 12
The biasing force F _C increases, the holder 15 is pushed up, and the first valve device 5a is brought into a closed state. From this point on, the refrigerant flowing into the high-pressure side casing 9 stops, so the pressure in the outlet pipe 9b of the high-pressure circuit A drops rapidly. Due to this pressure drop, the high pressure valve 16 is further attracted to the valve seat body 9c, and leakage is reduced. Note that after the rotary compressor 1 stops, the short time t until the first valve device 5a closes must be about 30 seconds or less. This period of 30 seconds or less depends on the size of the refrigeration system and the size of the rotary compressor 1, but for about 45 seconds to 1 minute after the refrigeration system has stopped, the liquid refrigerant condensed in the condenser 4 flows into the capillary reach tube. This is because the first valve device 5a only needs to be closed before this occurs, since the first valve device 5a flows into the first valve device 6 and performs a normal refrigerating action. For that purpose, the minute time t
It is necessary to make it as small as possible, and for this purpose, the first valve device 5a is closed when the differential pressure ΔP is large. On the other hand, the pressure difference between the high-pressure side casing 9 and the low-pressure side casing 10 at low outside temperatures gradually decreases, and if the differential pressure ΔP is set to a large value, the first valve device 5a will be in the closed state even when the refrigeration system is in operation. No action is taken. Based on the above, the differential pressure ΔP is set to around 2 kg/cm ² . When the refrigeration system is started, the pressure in the low-pressure circuit B becomes low instantaneously, and the pressure-responsive element 12 is pulled down, and the high-pressure valve 16 integrated with the pressure-responsive element 12 via the holder 15 is lowered.
The first valve device 5a opens and performs normal refrigeration. In particular, in the relationship between the connection member 15 provided on the pressure-responsive member 12 that moves up and down, the high-pressure valve 16 provided on this connection member 15, and the valve seat body 9c, changes in the pressure-response element 12 or the holder 1
Since the high pressure valve 16 is movable despite the mounting error between the valve seat body 9c and the valve seat body 9c, the valve seat body 9c can be reliably closed. Further, the holder 15 is a pressure-responsive element 1
Since the protrusion 15a of the pressure-responsive element 12 is crimped and fixed to the through-hole 12a, the pressure-responsive element 12 will not be thermally deformed during assembly, and its characteristics will not change. Furthermore, since the adjustment device for adjusting the biasing force of the coil spring 13 is integrally provided on the valve seat body 10c, the differential pressure ΔP can be set accurately by rotating the screw 10d, and the adjustment device has a simple structure and is inexpensive. be.

As is clear from the above explanation, the fluid control valve for a refrigeration system of the present invention has a first valve interposed on the high pressure circuit side.
and a second valve device interposed on the low-pressure circuit side, the first valve device and the second valve device being pressure responsive to a pressure difference between the high-pressure circuit and the low-pressure circuit. The first valve device is divided by a response element, and the first valve device includes a high-pressure valve that opens and closes the high-pressure circuit, and a connecting member that is connected to the pressure-response element and holds the high-pressure valve, and the second valve device is configured to perform a check valve operation, and the pressure responsive element is configured to close the first valve device when the pressure difference is below a predetermined value, and further includes a high pressure valve held by the connecting member. Since the first valve device is designed to be able to move over a short distance, the first valve device responds to the pressure by opening when the pressure in the low pressure circuit is low and closing when it is high. When the equipment is in operation, normal refrigerant circulation is performed, and when the refrigeration equipment is stopped, the second valve device, which has a check valve function, immediately closes, and at the same time the pressure in the low pressure circuit suddenly increases, causing the first valve device to close. Since the valve is closed during a short period of time when the refrigerant is flowing out to the pressure reducing device, superheated gas in the closed container and the condenser is prevented from flowing into the evaporator via the suction line and the pressure reducing device. Therefore, it has a greater power saving effect than a type without a fluid control valve, and is cheaper than a type controlled by a solenoid valve.Furthermore, it does not require power for control, does not require a control circuit, and requires no extra electrical wiring. It also has the characteristics of not requiring any noise, and since it operates smoothly, it does not generate noise. In addition, the high-pressure valve is held movably with a small gap in the holder, so even if there is a mounting error between the valve seat body and the holder, the high-pressure valve closes centripetally to the valve seat body, resulting in less leakage. Valve function can be maintained. or,
For the first valve device, the pressure-responsive element is made with a through hole, the protrusion of the holder is inserted, and then the holder is crimped and sealed, so there is no characteristic change due to heat compared to fixing by welding or brazing. It is simple, inexpensive, and can reliably maintain airtightness.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of a refrigeration system equipped with a fluid control valve for a refrigeration system according to an embodiment of the present invention, and is a cross-sectional view of the main parts during operation, and Fig. 2 is a fluid control valve corresponding to Fig. 1 when it is stopped. 3 is a sectional view of the main part of the high-pressure valve part, FIG. 4 is a sectional view of the main part of the spring biasing force adjustment device, and FIG. 5 is a pressure change diagram of the refrigeration system shown in FIG. 1. . A...High pressure circuit, B...Low pressure circuit, 5...Fluid control valve, 5a...First valve device, 5b...Second valve device, 12...Pressure responsive element, 15...Holder (coupling) member), 15c... gap, 16... high pressure valve.

Claims (1)

[Claims] 1 A first valve device interposed on the high pressure circuit side and a second valve device interposed on the low pressure circuit side, the first valve device and the second valve device being connected to the high pressure circuit side. The first valve device is divided by a pressure-responsive element that responds to a pressure difference in a low-pressure circuit, and includes a high-pressure valve consisting of a ball valve that opens and closes the high-pressure circuit, and a high-pressure valve that is connected to the pressure-responsive element and holds the high-pressure valve. the second valve device is configured to perform a check valve operation, and the pressure responsive element is configured such that the first valve device closes when the pressure difference is below a predetermined value. The connecting member has a protrusion, the protrusion is inserted into a through hole provided in the pressure responsive element and fixed by pressure, and a recess for accommodating a high pressure valve, the opening side of the recess being A fluid control valve for a refrigeration system, which is formed by caulking to have a diameter smaller than that of the high pressure valve, and is movably held within the recess with a small gap.