JPH025346Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a damper-type temperature regulator used in refrigerators, freezers, etc., which can automatically adjust the flow rate of cold air to the refrigerator compartment side.

Conventional damper-type temperature regulators seal refrigerant gas in a heat-sensitive tube, capillary tube, and bellows, displace the bellows by the expansion and contraction of the gas, and use a push rod to transfer this displacement into a duct that forms a cold air passage. The air is transmitted to a swinging flapper, which adjusts the flow rate of cold air into the refrigerator compartment to maintain a constant temperature inside the refrigerator compartment. For this reason, when the temperatures of the heat-sensitive tube and the bellows become close to each other, the temperature at which the flapper opens and closes due to the temperature of the heat-sensitive tube changes due to the influence of temperature changes in the bellows. Therefore, a small-capacity heater is attached to the bellows. The temperature is maintained at a constant level above the temperature of the heat-sensitive tube, and the degree of opening of the flapper can be adjusted simply by changing the temperature of the heat-sensitive tube. Normally, the temperature of the refrigerator compartment is adjusted to around +3°C, but at this time, the temperature of the bellows part is maintained at around +10°C, and the temperature in the refrigerator compartment is detected by a heat-sensitive tube installed inside the refrigerator compartment. The bellows are expanded, the push rod is pushed out, the flapper opening degree is increased, the amount of cold air to the refrigerator compartment is increased, and the temperature of the refrigerator compartment is lowered. Conversely, when the temperature in the refrigerator room becomes low, the bellows contract, the push rod is retracted, the opening degree of the flapper becomes smaller, the amount of cold air decreases, and the temperature in the refrigerator room increases. This conventional damper-type temperature controller has a heater installed in the bellows section to ensure stable damper opening/closing operation in response to temperature changes in the heat-sensitive tube.However, since the bellows heater is installed inside the refrigerator compartment, In order to cool down the amount of heat generated and the equivalent amount of heat generated,
The disadvantage is that the power consumption of the refrigerator increases.

An object of the present invention is to provide a refrigerator temperature regulator that operates stably in response to temperature changes within the refrigerator compartment without the need for a heater for heating the bellows. When liquid refrigerant is sealed in heat-sensitive tubes, capillary tubes, and bellows, expansion and contraction of the bellows occurs at the interface where liquid refrigerant and gas refrigerant coexist (hereinafter referred to as coexistence surface), no matter where the liquid refrigerant is located. Replacement of refrigerant/gas refrigerant (vaporization from liquid refrigerant to gas refrigerant or condensation from gas refrigerant to liquid refrigerant)
Focusing on the fact that the coexistence of liquid refrigerant and gas refrigerant is determined by the coexistence of liquid refrigerant and gas refrigerant, the coexistence of liquid refrigerant and gas refrigerant is created only in the heat-sensitive tube installed in the refrigerator compartment, and the temperature inside the refrigerator is controlled. It is designed to respond sensitively to almost equal temperature changes in the heat-sensitive tube.
This allows the bellows to expand and contract reliably in response to temperature changes within the refrigerator compartment, and eliminates the need for a heater attached to the bellows. That is, the bellows is housed in a closed space formed by the main body of the temperature regulator, and the main body of the temperature regulator is installed adjacent to a cold air outlet through which cool air from the cooler flows;
This keeps the temperature of the bellows lower than the temperature of the heat-sensitive tube, filling the inside of the capillary tube and the inside of the bellows with condensed liquid refrigerant, and also maintains the temperature for a refrigerator where liquid refrigerant and gas refrigerant coexist in the heat-sensitive tube. It is used as a regulator.

The present invention will be explained with reference to an embodiment shown in FIGS. 1 to 3. 1 is a freezer compartment provided at the top of the refrigerator, and 2 is a refrigerator compartment. 3 is a temperature controller for the refrigerator compartment installed at the back of the refrigerator compartment. The cold air in the freezer compartment circulates as shown by the solid line arrow, and the cold air in the refrigerator compartment partially bypasses the freezer compartment outlet, passes through the duct in the temperature controller 3, and then circulates as the broken line arrow. Keep the room temperature at -18°C and the inside of the refrigerator at 1-5°C. 4 is a main body component of the temperature regulator 3;
5 is a flapper provided in the cold air passage. The flapper 5 can be moved around 5c to block the cold air outlet. 6 is a spring, one end of which is a flapper 5
and the other end is fixed to the main body 3. Reference numeral 7 denotes a push rod which is slidable in order to transmit the expansion and contraction displacement of the bellows 8 disposed at the bottom to the flapper 5. 9 is a capillary tube, and 10 is a heat-sensitive tube. The capillary tube 9 connects the bellows 8 and the heat-sensitive tube 10. 9c is a notch provided in the capillary tube, and through this notch 9c, the inside of the heat-sensitive tube 10 and the inside of the bellows 8 are communicated, and the refrigerant sealed in the heat-sensitive tube can move to the bellows side. 11
is a heat insulating material that surrounds the temperature regulator 3 and forms a cold air passage inside the main body 4. 12 is a temperature controller 3
This is a sealing material that is attached to the surface of the inner box in the refrigerator compartment in which the temperature controller is installed, and can seal the space 13 surrounded by this sealing material 12, the heat insulating material 11, and the temperature controller body 4.
The operation of this embodiment configured as above will be explained. A heat-sensitive tube 10 provided inside the refrigerator compartment detects the temperature inside the refrigerator compartment. When the temperature inside the refrigerator rises, the gas refrigerant inside the heat-sensitive tube expands, pushing up the push rod 7 that can slide on the top of the bellows 8, and the flapper 5 provided at the tip of the push rod 7 pulls the spring 6. It opens, the cold air passage expands, and the cold air from the cooler passes through the cold air passage provided between the main body 4 of the temperature controller and the heat insulating material 11, and flows into the refrigerator compartment. When the temperature in the refrigerator compartment decreases, the gas refrigerant in the heat-sensitive tube contracts, and the force pushing up the push rod 7 provided at the top of the bellows 8 becomes smaller, and the flapper 5 is pulled in the direction of closing the cold air passage by the spring 6, and this spring The compression force of 6 pushes the push rod 7 down in the direction in which the bellows 8 contract, and the amount of cold air from the cooler decreases. By repeatedly opening and closing this flapper, the refrigerator compartment can be maintained at a constant temperature. Next, the behavior of the refrigerant sealed in the heat-sensitive tube 10, capillary tube 9, and bellows 8 will be described. The liquid volume of the refrigerant to be sealed
V _L , bellows 8 and capillary tube 9
The liquid volume of the refrigerant, V _L , was selected to satisfy the following equation, where V _B is the internal volume of the tube, and V _S is the internal volume of the heat-sensitive tube.

V _S > V _L > V _B The enclosed refrigerant is condensed and liquefied starting from the gas refrigerant present in the lowest temperature part of the heat sensitive tube 10, capillary tube 9, and bellows 8. At the beginning of operation of the refrigerator, both the bellows 8 and the heat-sensitive tube 10 are in a high temperature state, so the push rod 7 is pushed upward and the flapper 5 is in a position to open the cold air passage. For this reason,
The cold air from the cooler hits the body 4 of the temperature controller and then flows out into the refrigerator compartment 2. Here, the state of the refrigerant sealed in the temperature regulator 3 at the initial stage of operation after the refrigerator is installed will be described. Bellow 8,
The liquid refrigerant sealed in the capillary tube 9 and the heat-sensitive tube 10 may exist on the bellows 8 side or on the heat-sensitive tube 10 side depending on the attitude of the temperature regulator 3 before it is installed in the refrigerator. I don't know if there are any. In other words, if the bellows 8 of the temperature regulator 3 is left at a lower position than the heat-sensitive tube before being installed in the refrigerator, the liquid refrigerant will be present on the bellows 8 side, and conversely, if the bellows 8 is placed at a position higher than the heat-sensitive tube 10. The liquid refrigerant that has been left in the heat-sensitive tube 10 is present in the heat-sensitive tube 10. If a temperature difference occurs between the bellows 8 and the heat-sensitive tube 10, due to the nature of the refrigerant, the liquid refrigerant and the gas refrigerant coexist, no matter where the liquid refrigerant is located, so the liquid refrigerant and the gas refrigerant are constantly replaced. and activate bellows 8. Therefore, the operation of the bellows 8 is determined by the temperature of the portion where the liquid refrigerant and the gas refrigerant coexist. As mentioned earlier, the volume of the liquid refrigerant is larger than the internal volume of the bellows 8, so if the bellows is left in a low position, the inside of the bellows 8 will be filled with liquid refrigerant, and the coexistence surface of the liquid refrigerant and gas refrigerant will be exists inside the heat-sensitive tube 10. Also, if bellows 8 is left in a high position,
As shown in the above equation, since the volume of the liquid refrigerant is smaller than the internal volume of the heat-sensitive tube 10, all of the liquid refrigerant and the gas refrigerant coexist within the heat-sensitive tube 10, and only the gas refrigerant exists within the bellows 8. First, the initial operating state of the refrigerator after installation will be explained. Cold air from the cooler hits the main body 4 of the temperature controller, and then flows out into the refrigerator compartment 2. When the main body 4 is cooled, the air in the sealed space 13 on the back side of the main body 4 is gradually cooled. This cooling rate is very small, as the internal volume of the closed space 13 is approximately 1/200 to 1/300 of the internal volume of the refrigerator compartment 2.
The cooling rate in this refrigerator compartment 2 is faster than the cooling rate in the refrigerator compartment 2.
The bellows 8 housed in the closed space 13 is cooled down earlier than the heat-sensitive tube 10 placed inside. Therefore,
At the beginning of operation, that is, immediately after the start of operation, even if the liquid refrigerant is on the heat-sensitive tube 10 side, the bellows 8 is cooled first, so the enclosed refrigerant passes through the notch 9c of the capillary tube 9 and condenses on the bellows 8 side. The refrigerant becomes a liquid refrigerant and accumulates inside the bellows 8. This movement of the liquid refrigerant is transient, and a surface where the liquid refrigerant and gas refrigerant coexist temporarily occurs within the bellows 8. When there is a coexistence surface within the bellows 8, the bellows 8 does not expand or contract. This is because there is a coexistence surface of liquid refrigerant and gas refrigerant on the heat-sensitive tube 10 side as well, which makes it easy to replace the gas refrigerant and liquid refrigerant.
That is, the pressure does not fluctuate until the gas refrigerant condenses into liquid refrigerant and accumulates in the bellows 8. Since the liquid refrigerant volume is larger than the internal volume of the bellows and capillary tube, the liquid refrigerant remains in the heat-sensitive tube 10, and the liquid refrigerant and gas refrigerant are mixed in the heat-sensitive tube 10. Therefore, the bellows can be expanded and contracted depending on the temperature of the heat-sensitive tube in which liquid refrigerant and gas refrigerant are mixed. By surrounding the bellows 8 with the heat insulating material 11 as in this embodiment, the temperature of the dense space around the bellows is always maintained lower than the temperature of the refrigerator compartment 2 during refrigerator operation, and the liquid refrigerant is inside the bellows 8. By doing so, the bellows can be stably extended and contracted. Furthermore, by placing the bellows 8 at a position lower than the bottom of the heat-sensitive tube 10,
More liquid refrigerant can be held within the bellows. When the bellows 8 is installed at a higher position than the heat-sensitive tube, a trap is provided in a part of the capillary tube 9 coming out from the heat-sensitive tube as shown in FIG. It is possible to prevent the refrigerant from returning to the heat-sensitive tube due to its own weight, and improve the accuracy of temperature detection by the heat-sensitive tube 10. When the liquid refrigerant condensed in the bellows on the low-temperature side falls to the trap 9t position due to its own weight, the liquid refrigerant in the trap is held down to that position by the internal pressure of the heat-sensitive tube on the high-temperature side, and the liquid refrigerant in the trap The high-pressure, high-temperature gas refrigerant passing through the tube condenses into liquid refrigerant one after another in the bellows, filling the area higher than the trap with liquid refrigerant, and finally filling the bellows with liquid refrigerant, causing liquid to flow inside the heat-sensitive tube. Gas becomes mixed. If the refrigerant is R-142b, for example, it is possible to push the liquid refrigerant up to about 1 meter.

This invention installs a bellow inside the temperature controller body that is exposed to cold air from the cooler, and covers the area around the bellow with an insulating material, so that the sealed space around the bellows is always lower than the temperature inside the refrigerator where the heat-sensitive tube is installed. With this configuration, the inside of the bellows and the capillary can be filled with liquid refrigerant, and liquid and gas refrigerants can be mixed in the heat-sensitive tube. The refrigerant and the gas refrigerant are constantly replaced, whereby the bellows 8 expands and contracts and the flapper 5 operates. By filling the bellows 8 side with liquid refrigerant, the heat capacity of the refrigerant on the bellows 8 side is made larger than that on the heat-sensitive tube 10 side, thereby slowing down the movement of the bellows 8 due to temperature changes on the bellows 8 side.
Temperature changes can be sensitively sensed due to the coexistence of gas refrigerant and liquid refrigerant on the heat-sensitive tube 10 side. Therefore, without having to install a heater in the bellows part to maintain the bellows part at a constant temperature as in the past, the flapper 5 can be stabilized in response to temperature changes in the heat-sensitive tube 10 corresponding to changes in temperature in the refrigerator compartment. In addition to having the effect of opening and closing the bellows, the area around the bellows, which is colder than the refrigerator compartment, is a sealed space, thereby eliminating frost build-up around the bellows, making it possible to provide a practical damper-type temperature controller for refrigerators. . In addition, according to this embodiment, by providing the bellows section at a lower position than the heat-sensitive tube, liquid accumulates in the bellows section faster and the flapper opens and closes more stably. When the capillary tube is set at a high position, a trap is provided in a part of the capillary tube to push the liquid refrigerant to a higher position than the heat-sensitive tube, and the flapper is opened and closed only by temperature changes in the heat-sensitive tube. Both can improve practicality.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a refrigerator-freezer, Fig. 2 is an external view of the temperature controller for a refrigerator according to the present invention, and Fig. 3 is a partial cross-section of the temperature regulator according to the present invention assembled into the cold room of the refrigerator. 4 are operation explanatory diagrams showing another embodiment according to the present invention. 1... Freezer room, 2... Refrigerator room, 3... Refrigerator temperature controller, 4... Temperature regulator main body member, 5...
Flapper, 6... Spring, 7... Push rod, 8... Bellow, 9... Capillary tube, 10... Heat sensitive tube, 11... Heat insulating material, 12... Sealing material, 13...
...closed space.

Claims (1)

[Scope of utility model registration request] A heat-sensitive tube, a bellows, each of which is filled with a refrigerant, and a capillary tube that communicates between the above two members, and a transmission means that transmits the displacement of the bellows due to expansion and contraction of the refrigerant to an opening/closing member of a cold air passage to a refrigerator compartment. The temperature controller for a refrigerator is equipped with a temperature controller body that forms a sealed space for accommodating the bellows, and the temperature controller body is installed adjacent to a cold air outlet through which cold air from the cooler flows. , wherein the heat-sensitive tube is installed in a refrigerator compartment, the capillary tube and the bellows are filled with a liquid refrigerant, and a liquid refrigerant and a gas refrigerant are present in the heat-sensitive tube. vessel.