JPH0593557A - Cooling cabinet - Google Patents

Abstract

PURPOSE: To efficiently cool the interior of a cabinet where a thermostat to control a compressor to be on or off is arranged. CONSTITUTION: This cooling cabinet is provided with a flow control valve 20 between the outlet of a capacitor 14 and the inlet of a capillary 18. This control valve 20 lets only the refrigerant of overcooled liquid flow, and when the overcooling of the refrigerant drops under the specified level, the control valve 20 closes to completely check the flow of refrigerant between the capacitor 14 and an evaporator 16. Then, in case that the compressor 12 is not performing the operation, the control valve 20 is kept always in close condition. When the compressor 12 operates and the overcooling of the refrigerant reaches the specified overcooling value, the control valve 20 begin to open, and vegulates the flow of the refrigerant, in proportion to the degree of overcooling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling cabinet, and more particularly to a freezing cabinet such as a household refrigerator and a freezer.

[0002]

2. Description of the Related Art Household refrigerators and freezer cooling cabinets have hitherto been constructed to reduce costs and improve reliability, but in order to meet these requirements, the structure is simplified. In addition, it is necessary to minimize the number of parts. Refrigerators or freezers generally include, in a circuit, a condenser, evaporator or evaporator,
It uses a vapor compressor with an optional accumulator and an airtight compressor driven by a fractional horsepower electric motor connected to a refrigerant flow limiting means provided between the condenser and the evaporator. For high energy efficiency, sufficient reser
It is desirable to use a relatively high duty cycle during the operating time of the compressor while maintaining ve). Thus, a thermostat responsive to the temperature in the cooling chamber is used to cycle the compressor as needed to maintain a predetermined temperature. Based on normal room temperature and absorption of heat into the cooling space through the insulation, the duty cycle of the compressor can be operated at 50% to 60%, leaving a reserve, Continuous operation is required under very high ambient temperature conditions or under conditions where doors are often opened to access the interior of the cooling chamber.

The flow restricting means are most often capillaries sized for optimum efficiency under the set of conditions of ambient temperature and cooling chamber internal temperature. Capillaries used as the only limiting means have the advantages of low cost, high reliability, and easy heat exchange with the return line from the evaporator to the compressor to increase efficiency.

Capillary devices that operate constantly at a single ambient temperature and constant load are significantly more efficient when the capillaries are sized to meet these conditions. When this is done and the device is operating under equilibrium conditions, the refrigerant at the condenser outlet where the refrigerant enters the capillary is saturated or is a slightly supercooled liquid. .. The liquefied refrigerant flows through the capillaries and the pressure is greatly reduced until it enters the evaporator, and the refrigerant evaporates in the evaporator and absorbs heat from the inside of the refrigerator or freezer.

[0005]

The refrigerant flows in a closed system,
Moreover, since the actual flow rate through the capillary depends on the pressure difference between the condenser pressure and the evaporator pressure, any change in the load conditions will affect the operation of the device. In the case of refrigerators and freezers, changes in operating conditions affect the load on the evaporator due to changes in the ambient temperature of the room, which affects the heat dissipation from the condenser, and the opening and closing of doors and the storage of warm items. Caused by changes in the conditions in the cooling chamber. Furthermore, the device operates on a cycle basis and retains storage capacity in the event of an emergency, so that the thermostat inside the refrigerator will turn on the cycle to the compressor.
When the off is performed and the compressor is off, the pressure is equalized throughout the device, removing the liquid refrigerant in the capillaries and allowing the capillaries to become completely filled with gas. Such changes in operating conditions often cause the cooling system to operate at sub-optimal conditions with respect to condenser and evaporator temperatures and pressures, compromising the energy efficiency of the system.

Some of these effects can be minimized by various methods. For example, in order to minimize the formation of flash gas in the capillaries, which tend to reduce the capillary action of the system, the capillaries are usually soldered and arranged to exchange heat with a return line extending from the evaporator to the compressor. Has been done. Since normal optimum conditions are such conditions, the capillaries are usually "loose", that is, when the device is operated at a duty cycle of about 50 percent, the evaporator fills ( It is sized to speed up flooding and reduce the restriction so that the suction and release pressures can quickly equalize when in the off part of the cycle.

Faster evaporator flooding allows the system to reach high operating efficiencies quickly, thereby reducing the total on-cycle compressor run time. When the evaporator is overfilled, this type of device allows gas to be introduced into the capillaries and directed directly to the evaporator. As the gas enters the evaporator from the condenser, it turns into a liquid and back into a gas, without the phase change necessary for effective cooling in the evaporator. This not only imposes a large mass flow on the compressor without cooling, but also carries heat to the evaporator, thus reducing the efficiency of the device. When the compressor is turned off at the end of the operating cycle, the pressure equilibrates relatively quickly between the condenser and the evaporator through the capillaries, allowing the hot gases and liquids to pass into the evaporator. This adds heat to the evaporator and reduces the overall efficiency of the device. However, the quick equalization described above allows a relatively low starting torque and low cost phase splitter compressor motor to be restarted after a short off cycle.

In contrast, the device is "tight"("tigh").
t ") ie when using more restrictive capillaries, the device has a slight improvement in efficiency during steady state operation, but the evaporator flooding is very slow at start-up,
Efficiency benefits are lost over the entire operating cycle. Furthermore, since the above equalization becomes longer,
The low starting torque that overcomes the residual back pressure in the condenser is not possible and the compressor will have difficulty starting during short off cycles.

In the case of larger cooling systems, these problems can be solved by using a controlled expansion valve as a limiting means instead of a capillary tube. Valves of this type are typically actuated by a refrigerant bulb which senses the temperature at a location in the device and which opens and closes a valve located at the inlet of the evaporator to alter the degree of restriction at this location. It uses a diaphragm or bellows. However, valves of this type are too large and too expensive to replace capillaries in small cooling devices.

The present invention is a cooling device for household refrigerators and freezers provided with a capillary limiting means, and a novel subcooling (subco) between the outlet of the condenser and the inlet end of the capillary.
It is an object of the present invention to provide a cooling cabinet that can improve operation and efficiency by disposing a flow control valve.

[0011]

SUMMARY OF THE INVENTION In accordance with the present invention, a cooling cabinet is provided. This cooling cabinet responds to the temperature inside the compartment, the compressor, the condenser, the evaporator disposed in the compartment, the capillary tube connecting the evaporator and the condenser in the closed circuit containing the first refrigerant, and the temperature inside the compartment. A thermostat for selectively driving the compressor to keep the temperature in the compartment within a predetermined range, and a flow control valve arranged between the condenser and the capillary tube, the flow control valve including the first flow control valve Forming a chamber of the first chamber, an inlet of the first chamber connected to the condenser, an outlet extending from the first chamber to the capillary, a valve seat provided at the outlet of the housing, and a second chamber. As described above, the movable wall member disposed in the first chamber and fixed to the housing is actuated by the movement of the movable wall member so as to come into contact with and separate from the valve seat. And a valve member when the subcooling of the first refrigerant in the first chamber becomes higher than a predetermined degree. Away from the valve seat, and the valve member is moved to engage the valve seat when the subcooling of the refrigerant in the first chamber is below a predetermined degree, and the valve member engages the valve seat. According to the constitution, the first refrigerant is prevented from flowing from the inlet to the outlet.

According to the invention, the evaporator is also in a closed circuit having a compartment, a compressor, a condenser, an evaporator arranged in the compartment and a return line containing the first refrigerant and extending from the evaporator to the compressor. And a condenser for connecting the capacitor and the condenser, a thermostat for selectively driving the compressor so as to keep the temperature in the compartment in a predetermined range in response to the temperature in the compartment, and the thermostat arranged between the condenser and the capillary. A subcooling flow control valve, the subcooling flow control valve comprising a housing, an inlet tube of the housing connected to the condenser, and an outlet tube extending from the housing to a capillary, the flow control valve at the inlet tube. When the supercooling of the refrigerant is higher than a predetermined level, open the control valve to open the condenser. The refrigerant to the capillary tube, and when the supercooling of the refrigerant in the inlet tube is lower than a predetermined degree, the control valve is closed to prevent the refrigerant from flowing to the capillary tube. A cooling cabinet is provided, wherein the housing is located adjacent to the compressor in the cabinet to bring the inlet tube into heat transfer contact with the return line.

Further, according to the present invention, the compartment, the compressor, the condenser, the evaporator disposed in the compartment, the outlet connected to the evaporator in the closed circuit including the first refrigerant, and the condenser are connected. Between the condenser and the inlet of the capillary, and a thermostat that selectively drives the compressor to keep the temperature in the compartment within a predetermined range in response to the temperature in the compartment. A flow control valve provided, the flow control valve comprising a housing forming a first chamber, an inlet of the first chamber connected to the condenser, an outlet extending from the first chamber to the capillary, and a housing The valve seat provided at the outlet at the outlet, the movable wall member disposed in the first chamber so as to form the second chamber and fixed to the housing, and the valve seat And a valve member that is actuated by the movement of the movable wall member so as to be separated from each other, the second chamber is filled with a predetermined saturation amount of the second refrigerant, and the valve member is the first refrigerant in the first chamber. Is separated from the valve seat when the subcooling of the refrigerant is higher than a predetermined degree, and the valve member is engaged with the valve seat when the subcooling of the refrigerant in the first chamber is lower than the predetermined degree. The first refrigerant is prevented from flowing from the inlet to the outlet by the engagement of the valve member with the valve seat, and the volume of the refrigerant in the space between the valve seat and the inlet of the capillary tube evaporates the refrigerant. Is the second
A cooling cabinet is provided which is small enough not to cool the chamber of the chamber and is adapted to move the valve member toward and away from the valve seat to reopen the closed valve. ..

[0014]

In the present invention having the above structure, the flow control valve is an internally self-contained unit for adjusting the flow of the refrigerant flowing through the control valve in proportion to the degree of supercooling.
Is. The control valve is set to close completely when the degree of subcooling falls below a certain minimum positive value,
Compressor equalizes system pressure
And when turned off to block the flow of hot refrigerant to the evaporator, it remains closed. When the compressor starts, the compressor must release pressure to the already high pressure condenser because no equalization has been done in the flow control valve. This pressure is lower than the normal operating pressure of the condenser due to cooling of the condenser during the off cycle, but as a motor using a compressor, it does not have a high rated horsepower in the operating state, but a motor with a large starting torque. is necessary. High starting torque is obtained by using a capacitor starting motor. When the compressor restarts, the pressure in the condenser rises until subcooled liquid appears at the outlet. When the outlet liquid reaches a certain minimum specified positive supercooling value, the flow control valve begins to open and the refrigerant flows through the capillaries into the evaporator. The flow control valve operates to increase the flow rate as the degree of subcooling increases.

In this device, the capillaries are significantly relaxed, that is, a significantly less restricted tube.
oser or lessrestrictive tube), the pressure drop is less than normal, the rest of the pressure drop is done through a flow control valve. Thus, the pressure drop across the capillary tube is kept proportional to the mass flow rate of the refrigerant, while the pressure drop across the flow control valve tends to be proportional to the degree of supercooling of the refrigerant at the condenser outlet. It is inversely proportional to the mass flow rate because the control valve opens more with some increase in mass flow. The flow control valve is
No gas enters the capillaries at any point in the operating cycle of the device as it closes before the degree of supercooling of the condenser outlet falls below a minimum specified value.

The flow control valve is a self-contained device that responds to the supercooling of the refrigerant that actually flows through the control valve. According to a preferred embodiment of the control valve, the inlet of the housing is connected to the outlet of the condenser, the outlet is connected to the inlet of the capillary and thus to the evaporator, which housing forms a first chamber between the inlet and the outlet. Form. A movable wall member in the form of a closed bellows is provided between the inlet and the outlet.
Installed in the room. The part or end adjacent the inlet is fixed relative to the housing and the opposite or movable part or end carries the valve element. A valve seat is mounted on the housing adjacent the outlet and is engageable by the control valve block to seal and block the flow of refrigerant from the inlet to the outlet when the control valve is fully closed. .. A second chamber filled with the saturated refrigerant is formed inside the bellows, and the refrigerant may be the same as the refrigerant of the device or a fluid having a saturation pressure higher than that of the refrigerant of the device. You can For better response, the second chamber extends back into the inlet tube and comes in for the most efficient heat transfer between the device refrigerant and the second chamber refrigerant. The second chamber has a tubular portion exposed to the refrigerant, and the temperature and the refrigerant in the second chamber are
Come closer to the room.

The minimum specific subcooling value or set point is such that the control valve does not open in the absence of subcooled liquid in the first chamber and is always closed before gas enters the capillary. It has to be chosen such that the supercooling pressure of the ambient refrigerant in the first chamber is sufficiently high. Also, the set point should not be too high, otherwise it will be difficult to increase the initial flow when the control valve opens after the device has started.

Furthermore, it has been found that the flow control valve operates with a faster response time both when opened and when closed when located close to the compressor and the return line extending to the compressor. .. The control valve is arranged vertically with the tube at the inlet of the control valve, which extends a short distance parallel to the return line leading to the compressor. The two tubes are arranged so that they can transfer heat by contact. this is,
This can be done by soldering the tubes together along the length of the contacts. This can also be done using a spring clip mounted over the two tubes, not only to keep the tubes in contact, but also to transfer heat between the tubes. The area of heat transfer contact should be as close as possible to both the compressor and the control valve body.

The control valve often opens again after the compressor has stopped and first closed, which causes the control valve to cool to a temperature below the set point at which the control valve opens. It was found to occur by evaporation of the liquid refrigerant. According to the control valve of the present invention, this cooling is caused by the volume of refrigerant on the outlet side of the control valve at the inlet of the capillary. This volume can be substantially removed by placing the filler plug in the valve housing on the outlet side of the valve orifice, or by reshaping the valve housing itself to reduce this space. The resulting control valve does not have a sufficient amount of refrigerant in this part, and with sufficient cooling by evaporation it is possible to cool the control valve and the valve capsule below the set point where the control valve begins to reopen, and thus The control valve can remain closed until the compressor is restarted.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 in detail,
A vapor compression chiller 10 commonly used in domestic refrigerators or freezers is shown schematically. The device 10 comprises a compressor 12, preferably an airtight electric motor drive, and a condenser 14 to which the output of the compressor 12 is connected.
And an evaporator 16 mounted inside the insulated compartment 22, the return line from the evaporator 16 being connected to the inlet of the compressor 12. The cooling device 10 is a closed recirculation system filled with an appropriate refrigerant such as R12, and the capillary tube 18 is an expansion control device in order to provide a necessary flow rate limiting device between the condenser 14 and the evaporator 16. Is used as. Although not shown in FIG. 1, a capillary 18 carefully formed to have a predetermined inner diameter and length has a heat transfer contact (h
It is connected to the line between the compressor 12 and the capacitor 14 by an eat conducting contact). According to the invention, the control valve 20 comprises a condenser 14 and a capillary tube 1.
It is connected by a line between the inlet end of 8 and.

In order to maintain the compartment 22 at a desired temperature,
An appropriate thermostat 19 operates in response to a sensing bulb 21 located in the compartment 22 to sense the compartment temperature. Thermostat 19
It operates via electrical contacts that turn on and off the supply of electricity from the supply line 23 to the electric motor that drives the compressor 12. Thus, when the temperature sensed by the temperature sensitive body 21 rises to a predetermined level as a result of the inflow of heat into the compartment 22, the contacts of the thermostat 19 provide a time for the compartment 22 to cool to a lower temperature. , The compressor 12 is closed so as to excite, which causes the thermostat 19
And the compressor 12 turns off the cycle until the temperature rises again to a predetermined level.

The duty cycle, which is the time that the compressor 12 is in operation, depends on the ambient temperature around the compartment 22 and other components of the system, as well as the compartment 2.
2 depends on other factors such as the thermal mass on the inside and the number of times the warm air outside enters by opening and closing the access door. Thus, in most cases,
The equipment is such that the compressor has a duty cycle of about 5
It is sized to have 0 percent run time, but this is especially so if the doors are often opened or closed or the ambient temperature is high. Similarly, the duty cycle will be much lower if the refrigerator or freezer is located in a location with low ambient temperature.

One embodiment of control valve 20 is shown schematically in FIG. 2 as a longitudinal cross-section. The control valve 20 comprises a short tubular valve housing 26 at one end of which is welded or soldered an inlet mounting member 28 forming a reduced diameter inlet opening 29 to which the tube from the condenser 14 is connected. .. At the other end of the housing 26, an outlet mounting member 30 having a reduced diameter outlet opening 31 which can be configured similarly to the inlet mounting member 28 and is connected to the capillary tube 18 via an appropriate mounting member is mounted. There is.

Although the internal structure of the control valve 20 is shown schematically, the internal mechanism includes an inlet plate 32 extending across the inlet side of the housing 26. The inlet plate 32 is formed with a plurality of through inlet openings 33 that provide sufficient area for the free flow of refrigerant from the inlet mounting member 28 to the first chamber 36 of the housing 26. The other end of the first chamber 36 extends in a sealed manner across the housing 26 and is axially aligned with the inlet mounting member 28 and the outlet mounting member 30 to form a valve seat 35 in the central opening. Is closed by.

Thus, the first chamber 36 is formed by the valve housing 26 and the two plates 32 and 34, and the actuating valve mechanism is located in this chamber. A boss 38 is formed inside the first chamber 36 of the inlet plate 32 to act as a sheet at one end of an elongated movable wall member or bellows 40. The other end of the bellows 40 is closed by the base 43 of the valve member 42.
2 has a tip 46 adapted to engage the valve seat 35. The bellows 40 has a valve member 42.
Is movable in the longitudinal direction so as to move in the first chamber 36 along the axis in a direction away from and in contact with the valve seat 35 carried by the outlet plate 34. Thus, the bellows 40 forms within the bellows 40 itself a second chamber 44 which is completely sealed from the first chamber 36 and which is calibrated and filled with a suitable refrigerant. The refrigerant can be the same refrigerant used in this device, such as R12, or R5
It may be a refrigerant having a higher vapor pressure under saturated conditions at the same temperature, such as 00. As long as the condition in the first chamber 36 is set such that the degree of supercooling of the refrigerant in the device is lower than a predetermined minimum value or set point, the amount of this refrigerant charge is set so that the control valve 20 is completely closed. Calibrated to ensure it is closed. Only if the supercooling exceeds the set point will the control valve 20 open to allow the supercooled liquid refrigerant to enter the capillary 18.

A tubular portion 48 is disposed protruding from the boss 38 and engages the base 43 of the valve member 42 under extreme cold conditions to move the valve member 42 away from the outlet plate 34. I am trying to limit it. An extension tube 49 is mounted within the tubular portion 48 and extends rearwardly through the inlet opening 29. The extension tube 49 is sealed and forms part of the second chamber 44. The extension tube 49 extends rearward through the inlet to make heat transfer contact with the incoming refrigerant, thereby allowing the second chamber 44 to
The delay in the response time of the control valve 20 is minimized by making the temperature of the internal refrigerant as close as possible to the temperature of the incoming refrigerant of the device. The tip 46 of the valve member 42 extending through the valve seat 35 provides a different orifice for the valve seat 35 as the valve member 42 moves to different axial positions in response to pressure and temperature changes within the control valve 20. Shaped to provide size.

When the compressor 12 is off and is not in operation for a period of time, the control valve 20 is closed, the tip 46 of the valve member 42 is in tight engagement with the valve seat 35, and the refrigerant is It reliably prevents flow from the inlet to the outlet and thus from the condenser 14 to the evaporator 16. When the compressor 12 is started after the off cycle, the remaining refrigerant is pumped from the evaporator 16 to the condenser 14,
Increase the pressure in 4. Since the refrigerant at the outlet of the condenser 14 is already at a relatively low temperature, the increase in pressure generated through the condenser 14 causes the refrigerant to be supercooled at the outlet of the condenser 14 and the inlet of the control valve 20. The increase in pressure acts on the refrigerant in the second chamber 44, which is maintained at the same low subcooling temperature as the incoming refrigerant, and the second chamber 4
Reduce the volume inside 4. This allows the bellows 40
Contracts and moves the valve member 42 toward the inlet, the tip 46 of the valve member 42 moves away from the valve seat 35, and the control valve 20 opens, causing refrigerant to flow into the capillary tube 18 and thus into the evaporator 16. It begins to flow. When the compressor 12 performs its initial start, the valve member 42 will open somewhat more gradually and the pressure drop across the control valve 20 will increase to account for the total pressure drop between the condenser 14 and the evaporator 16. Only a small portion will occur through the capillaries 18. As the valve member 42 moves further away from the valve seat 35, the pressure drop across the restricting means reduces the pressure drop across the control valve 20 and increases the pressure drop across the capillary tube 18, thus increasing the total mass of the refrigerant. The flow rate increases. When the evaporator 16 is warmed to a temperature substantially higher than the normal operating temperature, such as a frost-free refrigerator or a freezer after a defrost cycle in which the evaporator 16 is further heated by a defrost electric heater, Since the flow rate of the refrigerant is maximum and the control valve 20 is in a significantly wide open state, substantially all of the pressure drop is in the capillary tube 18, and therefore the capillary tube 18 is in this state under this condition. It must be sized to allow.

When the compressor 12 continues to operate in the on-cycle, the cooled compartment 22 continues to cool, and the temperature of the evaporator 16 also drops. Thus, the total mass flow rate of the refrigerant is reduced, the subcooling at the outlet of the condenser 14 is reduced, and the valve member 42 moves closer to the closed position. However, the control valve 20 remains open as long as a subcooling condition exists at the outlet of the condenser 14.

If the compressor 12 is stopped for any reason, such as by the operation of a thermostat 19 which detects the lowest temperature in the compartment 22, no refrigerant will flow to the condenser 14 and the pressure at the outlet will be the liquid refrigerant control valve. It tends to rise as it continues to flow through 20 to the capillary 18. However, as soon as the pressure reaches a set point that is still within the subcooling range, the valve member 42
Is closed and the tip 46 seals the valve seat 35, preventing further refrigerant flow from the condenser 14 to the evaporator 16. This ensures that no steam enters the evaporator 16 and as long as the compressor 12 is off cycle.
It prevents heat transfer from the condenser 14 to the evaporator 16. When the refrigerant becomes higher than the supercooling temperature and vapor enters the evaporator 16, the efficiency of the device decreases, so blocking the flow of the refrigerant during the off-cycle heats the evaporator 16 and thus the compartment 22. Prevent heating. Such heating will occur in the absence of the control valve 20. The pressure in the condenser 14 continues to drop from the cooling of the refrigerant during the off-cycle of the compressor 12, but when the compressor 12 restarts at the beginning of the next on-cycle, there is a large back pressure on the discharge side of the compressor 12. Is still present, and in the presence of this back pressure, the condenser 14 and evaporator 16
A much higher starting torque is required from the compressor 12 than would be required to equalize the pressures between and. This can be eliminated by using a high starting torque electric motor for the compressor 12, and if a compressor starting type motor is used for the compressor 12, a sufficient starting torque can be easily obtained.
It is possible to eliminate the problem related to the restart of item 2.

When the compressor 12 is restarted, the pressure differential between the condenser 14 and the evaporator 16 caused by the closing of the control valve 20 causes the operating conditions to be reestablished more quickly than if the pressures were equal. Since the evaporator 16 is refilled more quickly, the operating time of the compressor 12 which performs a predetermined cooling during the on-cycle is shortened.

Another embodiment of the control valve is shown at 58 in FIG.
It can be arranged in the device shown in FIG. 1 in the same manner as the control valve 20 shown in FIG. The control valve 58 includes a housing 60 having a cup-shaped inlet member 61 and an outlet member 62, each member 61 and 62 including a peripheral flange 63 and 64, respectively. Disposed within the housing 60 is a transverse partition member 65 which also has a peripheral flange 66 clamped in a sandwich between the flanges 63 and 64, which is brazed or welded to the flanges 63 and 64. In this way, an integrated closed housing 60 can be provided. The inlet member 61 is provided with a central inlet mounting member 67 connected to the condenser 14, and the lower or outlet member 62 is provided with an outlet mounting member 68 connected to the capillary tube 18. When the control valve 58 is located in the device, the inlet mounting member 67 is at the top and the mounting member 67 is
It is preferable to arrange so that the axial alignments of and 68 are substantially vertical. The control valve 58 is typically a capacitor 1
4 should be located low in the device to ensure liquid flow from 4 to the inlet attachment 67.

The partition member 65 is a first member formed inside the housing 60 between the inlet member 61 and the partition 65.
Chamber 71 (inlet chamber) and an outlet chamber 72 formed between the partition 65 and the outlet member 62. Entrance room 71
A support plate 74 is disposed inside the partition chamber 65 with a predetermined distance therebetween, and the support plate 74 is fixed to the flange 66 and the partition 65 in the inlet chamber 71 by welding or soldering to the outer peripheral edge portion 76. have.
The support plate 74 has a plurality of openings 77 formed on both sides of the support plate 74 so as to freely communicate with each other in the inlet chamber 71.

A movable wall member in the form of upper and lower diaphragm members 81 and 82 is disposed between the support plate 74 and the partition 65. The diaphragm members 81 and 82 are sealed to each other at the edge portion 83 to form a second chamber 80 therebetween. The upper diaphragm member 81 is fixed to the support plate 74, and the lower diaphragm member or movable diaphragm or wall member 82.
Carries a cup 84 secured to it by welding or brazing on the underside. The cup 84 carries a valve seat 86 which may be formed from polytetrafluoroethylene or any suitable rubbery elastic member that is sufficiently compatible with the refrigerant of the device. The valve seal 86
It penetrates through the partition member 65 and comes into contact with a valve seat 87 formed around an opening 88 which provides a sole means of communication between the inlet chamber 71 and the outlet chamber 72. If desired, the cup 84 or other member engages the partition 65 to limit movement of the cup 84 and seal 86 relative to the valve seat 87, thereby effecting a cooling flow or set on the material forming the seal 86. Can minimize the effect of.

To hold the upper diaphragm member 81 in place, the upper diaphragm member 81 is attached to the mounting member 9
0 flange 91, which is also held in place relative to the underside of support plate 74 by beads 92 formed on mounting member 90 above support plate 94. An opening 94 is formed in the upper end of the mounting member 90, and the mounting member 90 is sealed at this end to the end of a tube 95 extending upward through the inlet mounting member 67. The tube 95 is sealingly fitted at the lower end to the opening 96 of the upper diaphragm 81, and the inside of the tube 95 and the second chamber 80 are in complete fluid communication with each other, but the inlet chamber 71 and the outlet chamber 72 are It is sealed from. Thus, the second chamber 80 is filled with a second refrigerant that is saturated in the same manner as the second chamber 44 of the control valve 20.

Thus, the control valve of FIG. 3 operates in the same manner as the control valve of FIG. That is, the entrance chamber 71
If the temperature and pressure conditions of the fluid in the inlet and inlet mounting member 67 are above the subcooling level, the valve seal 86
Closely engage valve seat 87 to prevent fluid communication between inlet chamber 71 and outlet chamber 72, thus preventing fluid from flowing through control valve 58. If subcooling conditions exist when the device is in operation, such subcooling will immediately cause the temperature and / or pressure in the inlet chamber 71, and thus the second chamber 80, to increase and the refrigerant to Since the valve seal 86 can be moved away from the valve seat 87 to flow through the control valve 58 in the same manner as, the refrigerant flows through the control valve 58 in the same manner as described above.

FIG. 4 shows a refrigerator 1 to which the present invention is applied.
It is a rear view of 10. The refrigerator 110 is provided with a cabinet 111 having a rear panel 112 having an opening formed in a lower portion thereof, which exposes a compartment 114 in which a compressor 116 and other components of the refrigerator device are incorporated. The compressor 116 moves upward along the rear panel 112 to the upper end of the serpentine tube condenser 121, which is appropriately installed at a predetermined distance from the rear panel 112 so as to perform sufficient air circulation and heat transfer. Exit line 118 connected to extending vertical line 119
Have.

At the bottom of the condenser 121, the refrigerant flows through the connecting tube 123 into the dryer cartridge 12
The outlet of the dryer cartridge 122 is connected via an inlet tube 126 to a flow control valve 124, which is preferably constructed as described below. The outlet side of the flow control valve 124 extends upward to the evaporator 129 mounted in the cabinet 111, and the outlet of the evaporator 129 causes the compressor 11 to pass through.
6 is connected to a return line 131 extending to 6 and a capillary tube 128 extending in a heat transfer relationship. As shown in FIGS. 5A and 6A, an inlet tube 126 between the dryer cartridge 122 and the flow control valve 124.
The portion 134 extends in parallel with the portion of the return line 131 close to the compressor 116 and in abutting contact with the portion 136. Because of the heat transfer between the portions 134 and 136, the responsiveness of the flow control valve 124 is improved by the heat transfer both when starting and stopping the compressor 116. Thus, when the compressor 116 is turned off, the hot compressor 116 returns heat via the return line 131 to allow the flow control valve 1 to operate.
Warming 24 will force it into the closed position. On the other hand, when the compressor 116 is started, a pressure drop is immediately generated in the return line 131 to lower the temperature, and the flow control valve 124 is cooled by cooling the refrigerant entering the control valve 124. Valve 124 opens faster and compressor 1
16 minimizes post-start delays and allows fluid to flow through the system.

A modified example of the flow rate control valve 124 is shown in FIG. 7, and the control valve 124 has substantially the same structure as the control valve 58 shown in FIG. Control valve 124
Has upper and lower housing members 143 and 146 having flanges 144 and 147 and in the form of opposing cup-shaped members, respectively. Flange 144 and 1
47 extends across the insides of the housing members 143 and 147, and inside thereof, the first chamber (upper chamber) 153 and the lower chamber 1
The flange 152 of the central partition member 151 divided into 54
Are fastened to each other around the edges on both sides of the. The dryer cartridge 1 is provided at the center of the upper housing member 143.
A mounting member is provided for receiving the inlet tube 126 from 22 while the lower honing member 146 is provided with a mounting member for receiving the outlet tube shown at 148 to which the capillary tube 128 is connected.

Within the upper chamber 153, there is disposed a support member or plate 156 which extends across the chamber at a predetermined distance from the partition member 151, and the support plate 156.
Is firmly fixed to the partition member 151 via the peripheral flange 157. The support member 156 is formed with a large number of openings 158 so that the refrigerant can freely flow through the support member to a position adjacent to the partition member 151. In the space between the support member 156 and the partition member 151, an assembly including an upper diaphragm member 161 and a lower diaphragm member 162 forming a closed second chamber 160 is arranged. The upper diaphragm member 161 is firmly fixed to the mounting member 164, the mounting member 164 is firmly fixed to the support member 156, and forms a part of the second chamber 160, and heat transfer is performed by the fluid in the upper chamber 153. Is connected to a tube 166 that extends upward in the inlet line for the distance between the and the fluid in the sealed second chamber 160. The lower diaphragm member 162 supports a cup 168 that is firmly fixed to the central portion, and the cup 168 is formed in the center of the partition member 151 and has an opening 171 in the valve seat.
And a resilient valve seal 169 adapted to make a valving contact with the control valve.

The upper and lower chambers 153 and 154 contain the device charge refrigerant, and the second chamber 160, which communicates with the interior of the tube 166, is sealed from the device coolant.
There is a saturated charge of the refrigerant that can be the same as the refrigerant of the device or have a higher vapor pressure at the same temperature under saturation.
The amount of saturated refrigerant in the second chamber 160 is carefully calibrated to ensure movement of the lower diaphragm member 162, and thus opening and closing of the control valve by contact and separation of the valve seal 167 with respect to the valve seat 171. It Thus, the amount of refrigerant is such that the upper chamber 153 and thus the second chamber 160
Sufficient to allow the control valve to close normally until the pressure and temperature inside reach a set point below the subcooled condition and the upper chamber 153 is filled with subcooled liquid from the condenser. Will be things. In such a supercooled state, the refrigerant in the second chamber 160 is compressed and the lower diaphragm member 162 moves upward to move the valve seal 1
Move 69 away from seal 171. When this is done, the control valve 124 opens and the refrigerant flows through the capillary tube 128.
The cabinet 111 can be cooled by passing through the evaporator 129. Thus, the compressor 116
When operating, the control valve 124 operates in a regulated manner to allow only supercooled liquid to enter the capillary tube 128. Therefore, when the degree of supercooling of the upper chamber 153 increases, the valve seal 169 moves further away from the valve seat 171, and the fluid flowing to the capillary increases, but when the degree of subcooling falls below the set point, the valve seal 169 moves. 169 moves closer to the valve seat 171, further limiting fluid flow into the capillaries.

The compressor 116 is installed in the cabinet 11.
When turned off by a control signal from the thermostat indicating that the temperature of the chamber of No. 1 is the lowest, the capacitor 121
The fluid is prevented from flowing further into the upper chamber 153, and the supercooling in the upper chamber 153 is reduced, so that the vapor is present at the outlet of the condenser 121. Without the control valve 124, vapor would enter the capillaries and thus the evaporator 129, causing a heating effect that somewhat impedes rapid cooling. To prevent this, when supercooling drops below the set point, control valve 124 closes and valve seal 169 moves into sealing engagement with valve seat 171 to prevent refrigerant from flowing from condenser 121 to capillary tube 128. Stop. Holding control valve 124 closed when compressor 116 is off eliminates heat transfer to evaporator 129 caused by the flow of gas through capillary tube 128, and
The amount of liquid left in the condenser 121 restarts the compressor 116 and the supercooled condition recreates fairly quickly after the control valve 124 opens. However, it is important that control valve 124 not open when compressor 116 is in the off cycle. It has been found that under certain conditions the control valve 124 reopens resulting in a loss of efficiency, which may be due in part to the presence of a large amount of refrigerant in liquid form in the lower chamber 154. It has been found that when the compressor 116 is stopped and the control valve 124 is closed, the liquid refrigerant in the lower chamber 154 gradually evaporates by flowing through the capillary tube 128 due to the differential pressure present. Due to the phase change of the refrigerant in the lower chamber 154, which changes to gas, from the other side of the partition member 151 to the position where the control valve 124 can be reopened due to the state in the diaphragm chamber 160, sufficient supercooling of the refrigerant occurs. Cooling is performed to absorb the heat. When this occurs in the off-cycle, the control valve 124 will not close again and the control valve 124 will be unable to prevent heat transfer to the evaporator 129.

To solve this problem, the lower chamber 15
Control valve 1 by reducing the volume of 4 absolutely
It has been found that it is possible to effectively prevent 24 from reopening. This fills the lower chamber 154 with a plug 173, which may be formed from any suitable plastic material such as nylon, and shortens the outlet tube 148 so that the inlet of the capillary tube 128 is as close as possible to the valve seat 171 of the opening. It can be done by Of course, the volume can be reduced by reforming the lower housing member 146 to minimize the volume of the lower chamber 154.

To further prevent re-opening of the control valve 124 when the compressor 116 is off, and to increase the response time that the control valve 124 reopens after the compressor 116 restarts, the control valve 124 may be replaced by the compressor 116. Is attached to a position adjacent to the control valve 124 and the inlet tube 126 of the control valve 124 is attached to the evaporator 129.
It has been found that it is desirable to actually make heat exchange contact with the compressor return line 131 from. Control valve 12
4 is an inlet tube 126 arranged along the vertical axis
And the outlet tube 148 should be attached vertically so that the upper end of the inlet tube 126 extends between the inlet tube 126 and the compressor 116 itself by extending a short distance parallel to the return line 131 as close as possible to the compressor 116. It is preferably bent at a predetermined angle so that the length between them is minimized. In order to make heat transfer contact, the inlet tube 126 and the return line 131 are connected to the metal clip 1 as shown in FIG.
It is held in abutting contact by 76. The metal clip 176 is preferably formed from a flat band of spring steel that extends in abutting contact around the inlet tube 126 and the return line 131, whereby the inlet tube 126.
And not only by abutting contact of the return line 131, but also by heat transfer between the inlet tube 126 and the return line 131 via clips extending a substantial portion around the inlet tube 126 and the return line 131. Done.

An alternative configuration is shown in FIG. 6A, where there is no clip 176 and a bead 179 of solder is secured to the inlet tube 126 and return line 131 to hold them in abutting contact. The heat is transferred through the beads themselves.

Inlet tube 1 extending to control valve 124
Since heat is transferred between the compressor 26 and the return line 131, the performance of the control valve 124 can be improved both when the compressor 116 is started and when it is stopped. When the compressor 116 is off,
Cooling of the control valve 124 and the second chamber 160 can be further prevented by the heat transferred from the relatively hot compressor 116 through the return line 131 to the inlet tube 126. Tube 166 in inlet tube 126
Form an extension of the second chamber 160, the inlet tube 126 is quickly warmed by the heat transferred from the return line 131, which heats the second chamber 160 and the tube 1.
It can be added to the refrigerant in 66, thus ensuring that the control valve 124 remains closed when the compressor 116 is off. Compressor 1
When 16 is restarted, the pressure in the return line 131 drops due to suction in the compressor 116, so the return line 131 immediately cools. This cooling in the return line 131 absorbs heat from the inlet tube 126 and further cools the interior of the second chamber 160 and tube 166, thus creating a subcooled condition and quickly opening the control valve 124 to condense the refrigerant. Inflow from 121.

Thus, the control valve 124 not only opens and closes quickly with the start and stop of the compressor 116, but also more quickly and by avoiding reopening during an off-cycle which results in a loss of efficiency of the system. It operates in a more reliable manner.

[0047]

As described above, in the present invention, since the flow control valve for supercooling is provided between the outlet of the condenser and the inlet end of the capillary, the cooling cabinet can be operated efficiently. ..

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a cooling device incorporating a flow control valve constructed according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a preferred flow control valve constructed in accordance with an embodiment of the invention.

FIG. 3 is a cross-sectional view of another preferred flow control valve constructed in accordance with an embodiment of the present invention.

FIG. 4 is a rear view of a refrigerator incorporating the cooling cabinet of the embodiment of the present invention.

5A is a partial front view showing a mode of attachment of a flow rate control valve, and FIG. 5B is a cross-sectional view taken along line bb of FIG. 5A.

FIG. 6A is a view showing another embodiment of the present invention.
6 is a partial front view similar to FIG. 6A, and FIG.
It is a bb line cross-sectional view of (a).

FIG. 7 is an enlarged vertical sectional view showing a modified example of the flow control valve.

[Explanation of symbols]

10 ... Cooling device, 12 ... Compressor, 14 ... Condenser, 16 ... Evaporator, 18 ... Capillary tube, 19 ... Thermostat, 20 ... Flow control valve, 21 ... Thermosensitive element, 22
... compartment chamber, 26 ... valve housing, 28 ... inlet mounting member, 29 ... inlet opening, 30 ... outlet mounting member, 31 ...
Outlet opening, 32 ... Inlet plate, 33 ... Inlet opening, 34
... outlet plate, 35 ... valve seat, 36 ... first chamber, 40 ... bellows, 44 ... second chamber, 46 ... tip portion,
49 ... Extension tube, 58 ... Control valve, 60 ... Housing, 61 ... Inlet member, 62 ... Outlet member, 67 ... Inlet mounting member, 68 ... Outlet mounting member, 71 ... Inlet chamber, 72
… Exit room, 110… Refrigerator, 111… Cabinet, 1
12 ... Rear panel, 114 ... Compartment, 116 ... Compressor, 118 ... Exit line, 119 ... Vertical line, 12
1 ... Condenser, 124 ... Flow control valve, 126 ... Inlet tube, 128 ... Capillary tube, 129 ... Evaporator,
131 ... Return line, 143, 146 ... Housing member, 153 ... Upper chamber, 154 ... Lower chamber, 156 ... Support plate, 166 ... Tube, 168 ... Cup, 169 ...
Valve seal, 171 ... Valve seat, 173 ... Plug, 176 ... Band, 179 ... Solder bead.

Front Page Continuation (72) Inventor William G. Nelson Minnesota, United States 56301, Matsu Cloud, Twenty Seventh Street South 2419 (72) Inventor Gary Earl Peter, United States, Michigan 49341, Rotskward, Highland Road 195 ( 72) Inventor Sammy Sea Beach, Junior, 13620, Chickstain Mile Road, Gauen, 49326, Michigan, USA

Claims (12)

[Claims] 1. A compartment, a compressor, a condenser, an evaporator disposed in the compartment, a capillary tube connecting the evaporator and the condenser in a closed circuit containing a first refrigerant, and the compartment. A thermostat for selectively driving the compressor so as to keep the temperature in the compartment in a predetermined range in response to the temperature, and a flow control valve arranged between the condenser and the capillary tube. The flow control valve has a housing forming a first chamber, an inlet of the first chamber connected to the condenser, an outlet extending from the first chamber to the capillary, and an outlet to the housing. A valve seat provided, a movable wall member disposed in the first chamber so as to form a second chamber and fixed to the housing, and the valve seat. And a valve member actuated by movement of said movable wall member toward and away from relative bets,
The second chamber is filled with a predetermined saturation amount of the second refrigerant, and the valve member is provided when the supercooling of the first refrigerant in the first chamber becomes higher than a predetermined degree. Away from the valve seat and the valve member is moved to engage the valve seat when the subcooling of the refrigerant in the first chamber falls below the predetermined degree;
A cooling cabinet, characterized in that the engagement of the valve member with the valve seat prevents the first refrigerant from flowing from the inlet to the outlet. 2. The cooling cabinet according to claim 1, wherein one part of the movable wall member is attached to the housing and the other part is a bellows attached to the valve member. 3. The cooling cabinet according to claim 1, wherein the second refrigerant is the same as the first refrigerant. 4. The cooling cabinet according to claim 1, wherein the second refrigerant has a higher vapor pressure than the first refrigerant at the same temperature. 5. A compartment, a compressor, a condenser, an evaporator disposed in the compartment, and a evaporator in a closed circuit including a first refrigerant and having a return line extending from the evaporator to the compressor. A capillary for connecting the condenser, a thermostat for selectively driving the compressor to keep the temperature in the compartment in a predetermined range in response to the temperature in the compartment, the condenser and the capillary. A subcooling flow control valve disposed between the subcooling flow control valve and a housing, an inlet tube of the housing connected to the condenser, and an outlet tube extending from the housing to the capillary tube. The flow control valve is provided with a predetermined degree of supercooling of the refrigerant in the inlet tube. When the temperature is higher than a certain degree, the valve is opened so that the refrigerant flows from the condenser to the capillary tube, and when the supercooling of the refrigerant in the inlet tube is lower than the predetermined degree, the valve is closed and the refrigerant is cooled. A cooling cabinet operative to prevent flow into the capillaries, wherein the housing of the flow control valve is located in the cabinet adjacent to the compressor to bring the inlet tube into heat transfer contact with the return line. .. 6. The cooling cabinet according to claim 5, further comprising heat transfer means fixed to both the tube and the return line. 7. The cooling cabinet according to claim 6, wherein the heat transfer means is a metal clip extending over the tube and the return line. 8. The cooling cabinet according to claim 6, wherein the heat transfer means is a soldered joint. 9. A compartment, a compressor, a condenser, an evaporator arranged in the compartment, an outlet connected to the evaporator and an inlet connected to the condenser in a closed circuit containing a first refrigerant. A capillary tube having a thermostat for selectively driving the compressor to keep the temperature in the compartment in a predetermined range in response to the temperature in the compartment, the condenser and the inlet of the capillary tube. A flow control valve disposed therebetween, the flow control valve comprising a housing defining a first chamber, and the first control valve connected to the condenser.
Of the chamber, an outlet extending from the first chamber to the capillary, a valve seat provided at the outlet of the housing, and a second chamber disposed in the first chamber to form a second chamber. And a movable wall member fixed to the housing, and a valve member actuated by the movement of the movable wall member so as to move toward and away from the valve seat.
Is filled with a predetermined saturation amount of the second refrigerant, and the valve member is removed from the valve seat when the supercooling of the first refrigerant in the first chamber becomes higher than a predetermined degree. And the valve member is moved to engage the valve seat when the supercooling of the refrigerant in the first chamber falls below the predetermined degree, and the valve member of the valve member The first refrigerant is prevented from flowing from the inlet to the outlet by the engagement of, and the volume of the refrigerant in the space between the valve seat and the inlet of the capillary tube is equal to that of the second refrigerant. A cooling cabinet which is sufficiently small so as not to cool the chamber and is adapted to reopen the closed valve by moving the valve member towards and away from the valve seat. 10. The space between the valve seat and the capillary tube forms a third chamber, the third chamber being substantially filled with an inert member. Cooling cabinet as described. 11. The cooling cabinet according to claim 10, wherein the inert member is a plastic plug. 12. The cooling cabinet according to claim 11, wherein the plastic is nylon.