JPS5950912B2 - refrigeration cycle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigeration cycle in which refrigerant is supplied by heating a refrigerant supply passage connected to a liquid reservoir with a heater.

For example, in a two-temperature refrigerator, a freezer compartment cooler and a refrigerator compartment cooler are usually used to separately cool the freezer compartment and the refrigerator compartment.

In this case, as an example of a method for controlling refrigerant supply to each cooler, liquid refrigerant that has been compressed by a compressor and liquefied by a condenser is temporarily stored in a liquid reservoir, and the liquid refrigerant stored in the liquid reservoir is When a predetermined amount of liquid is exceeded, refrigerant supply to the freezer compartment cooler is started, while a predetermined portion of the refrigerant supply passage connecting the liquid reservoir and the refrigerator compartment cooler is energized or disconnected depending on the refrigerator room temperature. The liquid refrigerant in the heated portion of the refrigerant supply passage is heated by a heater, and the pumping action of the bubbles is used to supply refrigerant from the liquid reservoir to the cooler for the refrigerator compartment. Something is being offered.

However, with this configuration, when a rise in the refrigerator room temperature is detected and power is started to the heater, the heated liquid refrigerant does not boil immediately even if the liquid temperature reaches the boiling point, and the temperature actually exceeds the boiling point. After being overheated, bumping occurs and bubbles are generated, so the refrigerant supply to the refrigerator room cooler is delayed from the time the heater is turned on until it reaches the overheated state where bumping occurs, during which time the refrigerator room temperature rises. There was a problem with this.

Therefore, in order to accurately control the temperature of the refrigerator compartment, it is desired to improve the structure described above so that the refrigerant supply can be started more quickly in response to the energization or disconnection of the heater. Ta.

The present invention has been made in view of the above-mentioned circumstances, and is made by forming an uneven part on the inner surface of the heater heating part of the refrigerant supply passage connected to the liquid reservoir, so that air bubbles are immediately removed when the liquid refrigerant reaches the boiling point of the refrigerant. An object of the present invention is to provide a refrigeration cycle that can accurately control refrigerant supply so that refrigerant can occur.

An embodiment in which the present invention is applied to a two-temperature refrigerator will be described below with reference to the drawings.

1 is a compressor, and its discharge port 1a is connected to a condenser 2
It is connected to the upper part of the liquid reservoir 4 via the capillary tube 3 and the capillary tube 3 in this order.

Reference numeral 5 denotes a refrigerator cooler installed in the refrigerator compartment (not shown), and 6 is formed into a box shape, the inside of which is used as a freezer compartment (not shown).
In the refrigerator compartment cooler 5, the outlet 5a of the refrigerator compartment cooler 5 is
is connected to the inlet 6a of the freezer compartment cooler 6, and furthermore, the outlet 6b of the freezer compartment cooler 6 is connected to the suction port 1b of the compressor 1 via a suction pipe 7.

Reference numeral 8 denotes a refrigerant pipe for supplying liquid refrigerant from the liquid reservoir 4 to the freezer compartment cooler 6, one end of which projects upward for a predetermined length from the bottom wall of the liquid reservoir 4, and the other end. The outlet 5 of the refrigerator compartment cooler 5 is connected to the inlet 6a of the freezer compartment cooler 6.
It is connected with a.

As a result, when the level of the liquid refrigerant discharged from the discharge port 3a of the capillary tube 3 and stored in the liquid reservoir 4 exceeds the upper end of the refrigerant pipe 8, the liquid refrigerant flows into the refrigerant pipe 8. The liquid refrigerant is supplied to the freezer compartment cooler 6 due to the pressure difference between the liquid reservoir 4 and the suction pipe 7.

Reference numeral 9 designates a control pipe as a refrigerant supply passage, which has one end slightly protruding upward into the liquid reservoir 4, and a midway portion bent into a substantially U-shape to direct upward.
The other end is bent into a substantially inverted U shape at a position higher than the inside of the liquid reservoir 4, and is connected to the upper end of a connecting pipe 10 communicating with the inlet 5b of the refrigerator compartment cooler 50.

By the way, the lower part of the rising part 9a of this control pipe 9 is a heating part 11 as a heater heating part heated by a heater to be described later, and the peripheral wall of this heating part 11 has a large number of inwardly recessed portions. A V-shaped groove 12 is formed, and the inner surface thereof is formed into an uneven shape (see FIG. 3).

13 is the aforementioned heater wrapped around the outer peripheral wall of the heating section 11;
This is for heating the heating part 11 of the control pipe 9 to boil the liquid refrigerant inside, and supplying the liquid refrigerant to the refrigerator compartment cooler 5 by the pump action of the bubbles.

Reference numeral 14 denotes a pressure equalizing pipe that connects the upper part of the liquid reservoir 4 and the upper end of the connecting pipe 10, and thereby balances the internal pressure of the connecting pipe 10 with the internal pressure of the liquid reservoir 4, so that the liquid reservoir The liquid refrigerant in the refrigerator compartment 4 is prevented from being supplied to the refrigerator compartment cooler 5 side due to the pressure difference.

Next, the operation of the above configuration will be explained.

First, in this embodiment, the motor of the compressor 1 is controlled to be turned on and off by a freezing room temperature detection switch which detects the freezing room temperature and turns on and off, and the heater 13 is basically controlled to be turned on and off by a refrigeration room temperature detection switch. shall be.

Now, when it is detected that the room temperature in the freezer and refrigerator compartments is above the set value, both of the above detection switches are turned on.
Therefore, the compressor 1 goes into operation and the heater 1
3 starts heating the heating part 11 of the control pipe 9.

In this state, the liquid refrigerant liquefied in the condenser 2 flows into the liquid reservoir 4 from the discharge port 3a of the capillary tube 3 and is temporarily stored there. There will be a natural influx of water.

A part of the liquid refrigerant stored in the liquid reservoir 4 is supplied to the freezer compartment cooler 6 via the refrigerant pipe 8, where it is gasified and returned to the compressor 1 via the suction pipe 7.

On the other hand, since the heating section 11 of the control pipe 9 is heated by the heater 13, the liquid refrigerant inside eventually begins to boil and generate many bubbles.

Therefore, the liquid refrigerant in the control pipe 9 and, in turn, the liquid refrigerant in the liquid reservoir 4 is continuously supplied to the refrigerator compartment cooler 5 via the control pipe 9 and the connecting pipe 10 by the pumping action of the bubbles. Most of it is gasified here, and the remaining part is all gasified in the freezer cooler 6 and returned to the compressor 1 via the suction pipe 7.

By supplying the refrigerant as described above, the refrigerator compartment cooler 5 and the freezer compartment cooler 6 produce a cooling effect, and the room temperature of each of the freezer compartment and the refrigerator compartment gradually decreases, and the refrigerator compartment is cooled to the set temperature. Then, the refrigerator room temperature detection switch turns off and the power to the heater 13 is cut off.

Then, the supply of liquid refrigerant from the liquid reservoir 4 to the refrigerator compartment cooler 5 is stopped, and only the freezing compartment cooler 6 continues to cool the freezer compartment.

In this state, if the refrigerator room temperature rises due to frequent opening and closing of the refrigerator compartment side door, the heater 13 is energized again and the supply of liquid refrigerant to the refrigerator compartment cooler 5 is restarted.

When the freezing chamber is cooled to the set temperature, the freezing room temperature detection switch is turned off to stop the compressor 1, and one cooling cycle operation is thus completed.

Then, when the freezing room temperature becomes equal to or higher than the set temperature, the compressor 1 is operated again, and one cooling cycle operation as described above is started.

By the way, in general, when heating a liquid to generate bubbles, if the heat transfer surface is smooth, there is no opportunity for bubble generation, so even if the liquid reaches its boiling point, it will not start boiling immediately.
A bumping phenomenon occurs in which boiling suddenly begins when a certain level of overheating is reached.

In a refrigeration cycle that uses bubble pump action to control refrigerant supply, 1. If a normal pipe with a smooth inner surface is used, the heater will be energized when it senses that the internal temperature has reached a predetermined level. However, since it takes a long time to generate bubbles and the time is not constant, effective temperature control cannot be performed.

Furthermore, in order to shorten the time from the start of energization to the generation of bubbles, if the heater capacity is made larger than necessary and the heater reaches an overheating state in a short time, the thermal effect on the outer periphery of the heater becomes large. There are problems such as an increase in power consumption.

In contrast, in this embodiment, a large number of grooves 12 are formed on the outer circumferential wall of the heating section 11 of the control pipe 9, thereby making the inner surface uneven and smooth boiling with microbubbles generated especially in the concave portions as nuclei. When the boiling point is reached, bubbles are generated immediately after the boiling point is reached.

Therefore, the refrigerant starts to be supplied to the refrigerator compartment cooler 5 within a short time from the start of energization to the heater 13, and the refrigerator compartment is quickly cooled.

In addition, since it is not necessary to bring the heating section 11 into a highly overheated state,
When the power to the heater 13 is cut off, the temperature of the liquid refrigerant immediately drops below its boiling point, and the generation of bubbles immediately stops.

Therefore, there is no risk that the refrigerant compartment will become appropriately cooled due to excessive supply of refrigerant.

That is, in this embodiment, it is possible to prevent a delay in the response of supplying or stopping the refrigerant due to the bumping phenomenon of the liquid refrigerant, so it is possible to suppress fluctuations in the temperature of the refrigerator room to a small extent, and to perform accurate temperature control of the refrigerator compartment. be able to.

Moreover, although it has such an excellent effect, since the unevenness on the inner surface of the control pipe 9 is formed by a large number of grooves 12 formed by recessing the peripheral wall inside, the processing can be performed from the outside and is relatively simple. This is easy, and the groove 12 can also act as a stop for the heater 13 wrapped around it.

As described above, the present invention supplies a refrigerant by heating a refrigerant supply passage connected to a liquid reservoir with a heater, in which the inner surface of the heater heating portion of the refrigerant supply passage is formed in an uneven shape. By doing so, it is possible to quickly respond to the heater's energization or disconnection to prevent the generation or stop of bubbles in the liquid refrigerant in the refrigerant supply passage, thereby improving the responsiveness of refrigerant supply control and ensuring accurate temperature control. A refrigeration cycle that can be controlled can be provided.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a configuration diagram of a refrigeration cycle, FIG. 2 is a sectional side view of a liquid reservoir, and FIG. 3 is a partially cutaway side view of essential parts. In the figure, 4 is a liquid reservoir (liquid reservoir part), 9 is a control pipe (refrigerant supply passage), 11 is a heating part (heater heating part), 13
is a heater.

Claims (1)

[Claims] 1 The refrigerant from the condenser side is stored in a liquid reservoir, the refrigerant supply passage connected to this liquid reservoir is heated by a heater, and the refrigerant in the liquid reservoir is pumped into the cooler by the pumping action of bubbles generated by this heating. 1. A refrigeration cycle in which refrigerant is supplied to the side, characterized in that an uneven portion is formed on an inner surface of a heater heating portion of the refrigerant supply passage.