JPH0395376A - Cooling device - Google Patents

Abstract

PURPOSE:To prevent a refrigerant accumulated in a refrigerant fluid reservoir from being increased and hence a fluid level from being raised from an open end of an inflow tube by interrupting a compressor after the refrigerant is directed to flow through both first and second coolers from a state where the refrigerant is directed to flow only through the second cooler. CONSTITUTION:When a compressor 62 is interrupted from a state where refrigerant is allowed to flow only through a refrigeration chamber cooler 18, the compressor 62 and a fan are forcedly operated independently of an output of a comparator for three minutes before the interruption of the compressor 62 and further a valve 65 is opened to direct the refrigerant to both coolers 44, 18, and after the elapse of three minutes the forced operation is interrupted at the time a flag F3 is reset. Accordingly, since a fluid level in an accumulator 68 is limited to L2 even after be interruption of the compressor 62, no refrigeration sound is produced. Although the period of the forced operation is determined to be a shortest one such that the refrigerant is also accumulated in the refrigerator chamber cooler 44 within a limit where no refrigeration sound is produced, it does not affect temperature control. Further, since the refrigerant fluid reservoir may be a typical one, separation function of gas/liquid refrigerant is not lost.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a cooling device that includes a first cooler and a second cooler, and further includes a refrigerant reservoir on the suction side of a compressor.

(Example) 2. Description of the Related Art Conventionally, there are conventional cooling devices such as refrigerator-freezers (for example, as shown in Japanese Utility Model Publication No. 58-32118).

In the structure shown here, when the refrigerator compartment needs to be cooled, the refrigerant passes through the refrigerator compartment cooler and then into the freezer compartment cooler, and when the refrigerator compartment does not need to be cooled, the refrigerant flows through the refrigerator compartment cooler. bypass and
By flowing refrigerant only through the freezer compartment cooler, independent temperature control of both the refrigerator compartment and the freezer compartment is achieved using a single compressor.

(c) Problems to be Solved by the Invention Here, a refrigerant reservoir (hereinafter referred to as an accumulator) is usually attached to the suction side of the compressor in order to prevent liquid compression in the kelp strainer. Further, a considerable amount of refrigerant is sealed in the refrigerant circuit so that sufficient cooling capacity can be exhibited with refrigerant flowing through both coolers.

Therefore, even if the compressor stops while refrigerant is flowing through both coolers, a certain amount of refrigerant will accumulate in both coolers, and the amount of refrigerant accumulated in the accumulator will be small. When the refrigerant is flowing, very little refrigerant flows into the refrigerator compartment cooler and almost no refrigerant accumulates, so the amount of refrigerant accumulated in the accumulator increases. Furthermore, when the compressor stops in this state, refrigerant flows into the accumulator from the high-pressure side through the capillary tube and the freezer compartment cooler, so a considerable amount of refrigerant accumulates in the accumulator.

FIG. 5 shows the general structure of this type of accumulator 6B. 68a is a tank having a predetermined capacity;
An inflow pipe 68b is inserted from the lower end of tank 68a and opens at a predetermined height within tank 68a. 68c is an outflow pipe that opens at the upper end of the tank 68a.

When refrigerant is flowing through both coolers, the refrigerant liquid level is L.
, and when the compressor stops from that state, the pressure rises to L due to the inflow from the high pressure side. On the other hand, when the liquid is flowing only to the freezer compartment cooler, the liquid level is approximately L, but when the compressor is stopped from that state, the liquid level is reduced to the inflow pipe 68b due to the inflow from the high pressure side.
It rises to L, which is higher than the open end of. Then, the refrigerant gas that continues to flow in from the inflow pipe 68b becomes bubbles and the liquid level reaches L. This causes the so-called refrigerant sound to pop.

In order to solve this problem, it is conceivable to raise the open end of the inflow pipe 68b, but in that case, the distance from the opening of the outflow pipe 68c will be close, so that the liquid refrigerant flowing from the inflow pipe 68b will directly flow into the outflow pipe 68c. There is a risk that fluid may flow into the tank and cause liquid compression at the humbpressor.

The present invention aims to solve this problem. (2) Means for Solving the Problems In the present invention, in a cooling device, refrigerant discharged from a compressor and passed through a condenser is allowed to flow through both a first cooler and a second cooler, or only into the second cooler. If the compressor is stopped with a refrigerant reservoir provided on the suction side of the compressor and refrigerant is flowing only into the second cooler, the first The refrigerant is made to flow through both the cooler and the second cooler.

(*> Effect) According to the present invention, before the compressor stops from the state in which refrigerant is flowing only through the second cooler, the refrigerant flows through both the first and second coolers and then stops. It is possible to suppress an increase in the amount of refrigerant accumulated in the liquid reservoir and prevent the liquid level from rising from the open end of the inflow pipe.

(g) Example Next, an example will be explained with reference to the drawings. Fig. 1 shows a front view of a refrigerator-freezer 1 as an example of the cooling device. The doors 2, 3 and 4, 5 are closed, and the bottom row is closed by a pull-out door 6. Furthermore, the doors 2, 3 and 4 are closed.
A control box 7 is protruded between 5 and 5. Figure 2 shows a front view of the refrigerator-freezer 1 excluding the doors 2, 3, 4.5 and the inner door 40, and Figures 3 and 4 are A-A in Figure 2.
,1! A heat insulating material 1o is filled by an in-situ foaming method between an outer box 8 that opens at the front and an inner box 9 built into the outer box 8, which is shown in a sectional view and a sectional view taken along the line B-B, respectively, to form a heat insulating box body 11. There is.

The inside of this heat insulating box 11 is divided into upper and lower parts by a heat insulating partition wall 12, forming an upper chamber and a lower chamber which are mutually partitioned and independent in terms of air circulation. The first freezer compartment 1 is divided into left and right sections.
4 and a second freezer compartment 15 are formed. At the back of the upper chamber, a vertical cooling chamber 17 is formed by a partition plate 16 spanning the entire left and right width, and a freezer compartment cooler 18 as a second cooler is vertically installed here.

A blower 2o for the freezer compartment is disposed in the cooling compartment 17 located above the cooler 18 and behind the partition wall 13. In addition, air outlets 21 and 22 are formed in the partition plates 16 corresponding to both the freezing compartments 14 and 15, respectively, and the first freezing compartment 14
An ice-making Suita port 23 is formed at the bottom, and an air outlet 24 is formed at the bottom of the second freezer compartment 15. Air outlet 21
23, 22, and 24 are connected to the freezer compartment cooler 18 by ducts 26 and 27 formed independently on a heat insulating plate 25 provided between the partition plates 16, respectively. The space 19, the air outlet 21, 22, and the duct 26 are communicated with each other. The blower 20 is a propeller fan that rotates and sucks in the cold air that has exchanged heat with the freezer compartment cooler 18 and sends it to the air outlets 21 and 22 and the air outlets 23 and 2.
The cold air blown out from the freezer compartments 14 and 15 from each of the freezer compartments 14 and 15 and circulated within the room is sucked through the suction port 28 at the front of the partition wall 12.

The inside of the first freezer compartment 14 is divided into upper and lower sections by a partition plate (not shown) attached in correspondence with the ice-making outlet 23, and the lower part thereof is used as an ice-making compartment for accommodating an ice-making tray (also not shown). If the first freezer compartment 14 and the second freezer compartment 15 are divided in this way and closed with separate seals s2 and s3, the open area of one side is smaller than if the whole is closed with one door, so The inflow of warm air when opened can be suppressed as much as possible. or,
Since the ice is cooled through a cold air circulation path independent of the refrigeration room (described later), there is no odor transfer to the ice produced. The lower chamber below the partition wall 12 is a refrigerator room 38. Insulating partition plate 39
partition plate 39 and inner s
40 forms an ice chamber 41. A cooling chamber 43 is formed by a partition plate 42 above the refrigerator compartment 38 at the back of the ice room 41, and a refrigerator compartment cooler 44 as a first cooler is installed vertically inside the cooling compartment 43. A refrigerator compartment air blower 45 is attached above the refrigerator compartment cooler 44, and a duct extending above the ice chamber 41 is installed on the partition plate 42 in front of the refrigerator compartment cooler 44.
a is formed. Refrigerator cooler 44 and partition plate 42
A heat insulating plate 48 is provided between them to form a duct 47 that extends downward from both sides of the cooler 44 from the space in front of the blower 45 and opens into the refrigerator compartment 38 . The blower 45 is a blower fan, which rotates to draw in the cold air that has exchanged heat with the refrigerator compartment cooler 44, and blows it forward into the ice room 41 through a plurality of discharge ports 49 formed on both sides of the duct 42a. While blowing out the cold air, the cold air is also supplied from the duct 47 to the refrigerator compartment 38 through the outlet 46. The cold air that has cooled the ice room 41 is drawn from the suction [150] formed in the partition plate 42, and the cold air that has cooled the refrigerator compartment 38 is drawn to the lower surface of the partition plate 39, extends from the partition plate 42, and flows from the front and side surfaces. The air then returns to the cooling chamber 43 through a suction duct 52 having a plurality of suction ports 51 .

A central shelf bracket 29 is attached to the duct 42a in a hanging manner, and shelf brackets 30, 30 are arranged opposite to each other on the left and right sides of the ice room 41.
is suspended. Two shelves 31.31 are supported in parallel between these shelf supports 29, 30.30. A manual damper D for opening and closing the discharge port 49 is installed in the central shelf support 29, so that the temperature inside the ice room 41 can be adjusted. Shelf support 30,3
There are through holes 30a, 30a that pass through the shelf 31. 31, and the inside of the ice greenhouse 41 can be cooled evenly.

The lower part of the refrigerator compartment 38 is further divided by a partition plate 53 and a partition front 54, and a container 56 with an upward opening supported by a frame 55 on the door 6 is housed below the partition plate 53, and the inside thereof is used as a vegetable compartment 57. 58 is a small container provided within the container 56. 60 is a machine room formed at the bottom of the heat insulating box 11;
A compressor 62 is installed on a base 61 provided at the inner rear part.

Next, FIG. 4 shows a refrigerant circuit diagram of the refrigerator-freezer 1.

The high-temperature, high-pressure gas refrigerant discharged from the compressor 62 flows into a condenser 64 disposed at an appropriate location in the refrigerator-freezer 1, radiates heat, and reaches a branch point P in a liquid state. From the branch point P, a series circuit of the solenoid valve 65, the first cracking tube 66, the refrigerator compartment cooler 44, and the freezer compartment cooler 18 connects a certain first flow path and a second key. It is divided into a second flow path consisting of a series circuit of the cold storage tube 67 and the freezer compartment cooler 18. That is, the second capillary tube 67 bypasses the solenoid valve 65, the first capillary tube 66, and the refrigerator compartment cooler 44. The flow path resistance value of the first Ki-Birari tube 66 is, for example, 5 kg/cm",
It is assumed that the weight of the second capillary tube 67 is 7 kg/(. to return to.

The inflow pipe 68b of the accumulator 68 is connected to the freezer compartment cooler 1.
The outlet pipe 18a of No. 8 and the outflow pipe 68c are connected to the suction side pipe 62a of the compressor 62, respectively. The gas-liquid mixed refrigerant flowing into the tank 68a from the inflow pipe 68b is separated into gas and liquid here, and the liquid refrigerant flows into the tank 68a.
Only the gas refrigerant accumulated in the gas refrigerant is sucked into the compressor 62 from the outflow pipe 68c. As will be described later, the solenoid valve 65 closes the flow path when cooling of the refrigerator compartment 38 is not required, so the refrigerant leaving the condenser 64 is transferred to the second
It flows only into the freezer compartment cooler 18 through the cavillary tube 67 . On the other hand, when the refrigerator compartment 38 needs to be cooled, such as when the refrigerator-freezer 1 is pulled down, the solenoid valve 65 opens the flow path.

When the solenoid valve 65 is open, the refrigerant that has exited the condenser 64 is divided into both flow paths at a substantially inverse ratio of the flow path resistance values of the two cavillary tubes 66 and 67, and flows into the first cavillary tube 66. The refrigerant whose pressure has been reduced in step flows into the refrigerator compartment cooler 44 and a part of it first evaporates there, and the unevaporated refrigerant subsequently flows into the freezer compartment cooler 1 and evaporates. On the other hand, the refrigerant whose pressure has been reduced in the second split tube 67 directly flows into the freezer compartment cooler 18, where it evaporates for the first time.

Next, FIG. 6 shows the electric circuit of the control device 70 of the refrigerator-freezer 1. 71 is a microcomputer. 74 is a sensor consisting of a negative characteristic thermistor that detects the temperature inside the refrigerator compartment 38, and the terminal voltage divided by the resistor 75 is sent to the converter 7.
No. 6-) Input is being made to the input terminal. Converter 76
A certain reference voltage is input to the (+) input terminal of the comparator 76 through variable resistors 72 and 77, and a positive feedback resistor 80 is connected between the (+> input terminal and the output of the comparator 76. The output is input to the microcomputer 71.A sensor 82 is a negative characteristic thermistor that detects the temperature inside the second freezing compartment 15.The terminal voltage divided by the resistor 83 is input to the (1) input terminal of the converter 84. A reference voltage made up of variable resistors 85 and 86 is input to the (+) input terminal of the converter 84, and a positive feedback resistor 8 is connected between the <+) input terminal of the converter 84 and the output.
7 is connected. The output of this comparator 84 is also input to the microcomputer 71. The terminal voltage of the sensor 82 is further input to the (-) input terminal of the comparator 88, the reference voltage formed by resistors 89 and 90 is input to the (+> input terminal, and the +> input terminal and A positive feedback resistor 91 is connected between the outputs.The output of this converter 88 is also input to the microcomputer 71.The output of the microcomputer 71 is connected to the blower 45.
and solenoid valve 65 are connected to the same output, and blower 20 and compressor 62 are connected to each other.

Next, the microcomputer 71 shown in FIGS. 7 to 8
Temperature control of both the freezer compartments 14 and 15 and the refrigerator compartment 38 will be explained based on the broached text. In step 100, it is determined whether or not the freezer compartment cooler 18 is being defrosted. If it is not defrosting, it is determined in step 101 whether the flag F3 is set. If it is reset, the process proceeds to step 102. .

In step 102, a determination is made based on the output of the comparator 84. The converter 84 sets a set temperature A of the second freezing compartment 15, which is set at a temperature between -18°C and -24°C by a variable resistor 85, depending on both input potentials, and
The temperature T1 of the second freezer compartment 15 detected by the sensor 82 is compared, and the upper and lower limit temperatures are set above and below the set temperature A by the resistor 87, and when the temperature T1 rises and exceeds the upper limit temperature, an output is generated. is set to a high potential (hereinafter referred to as "H"), and when the temperature T1 decreases to below the lower limit temperature, the output is set to a low potential (hereinafter referred to as r L ). The microcomputer 71 proceeds to step 103 when the output of the converter 84 becomes rH, and proceeds to step 10 if the output is rL.
Proceed to step 6.

In step 103, a determination is made based on the output of the comparator 76. The converter 76 uses both input potentials to generate a set temperature B of the refrigerator compartment 38, which is set at a temperature between 0°C and 4°C by the variable resistor 76, and a temperature T2 of the refrigerator compartment 38 detected by the sensor 74. The upper and lower limit temperatures are set above and below the set temperature B using the resistor 80, and when the temperature T2 rises and exceeds the upper limit temperature, the output is set to l″H.
”, and when the temperature T2 decreases to below the lower limit temperature, the output is set to “L”. When the output of the converter 76 becomes r H , the microcomputer 71 performs step 105.
If the flag is l″L, the flag F2 is set in step 104, and in either case, the process proceeds to step 111, where the compressor 62 is operated. That is, when it is necessary to cool the second freezer compartment 15 or the refrigerator compartment 38, the compressor 62 is operated. As will be described later, even in step 120, step 10
The same process as in 3 is performed, and the output of the converter 76 is "L".
If so, the process proceeds to step 122, and if the flag F3 has been reset, the valve 65 is closed and the blower 45 is stopped in step 124. That is, the flag F2 is set while the valve 65 is closed and the refrigerant is flowing only to the freezer compartment cooler 18.

In step 106, the same processing as in step 103 is performed, and if the output of the humidifier 76 is "H", the process proceeds to step 105, and if it is "rL", the process proceeds to step 1o7. Step 1
It is determined in step 07 whether the work flag F2 is set, and if it is reset, the compressor 62 is stopped in step 110. If the flag F2 is set, step 1
Proceed to step 08, set brag F3, then step 1o
At step 9, the microcomputer 71 sets the timer TM2 as its function to 3 minutes, and proceeds to step 111.

From steps 110 and 111, the process proceeds to step 112, where it is determined whether the flag F3 is set. If it is set, timer TM2 is subtracted at step 113. At step 114, it is determined whether the count of timer TM2 is 0. If not, the process proceeds to step 116, and if it is 0, the flag F3 is reset in step 115. That is, the flag F3 is set in step 10B when the refrigerant is flowing only through the freezer compartment cooler 18 and cooling of both compartments 15 and 38 is no longer necessary, and 3 minutes later, the flag F3 is set in step 11.
It is reset at 5.

Next, in steps 116 and 117, both coolers 44 and 18
It is determined whether or not the defrosting is being performed. If neither is being defrosted, the process advances to step 118 and a determination is made based on the output of the converter 88. The converter 88 is connected to the resistor 89 due to the potential of both people.
In step 90, the abnormal temperature C of the second freezing compartment 15 set at a temperature of, for example, -12°C is compared with the temperature T1 of the second freezing compartment 15 detected by the sensor 82, and the temperature T1 set by the resistor 91 is compared. When T1 exceeds the abnormal temperature with some hysteresis, the output is set to r H , and when it is lower than that, the output is set to "L". If the output of the comparator 88 is "L", the microcomputer 71 proceeds to step 120, performs the same process as step 103, and outputs the output of the comparator 7
If the output of valve 65 is r H , then in step 123 the valve 65 is
is opened and the blower 45 is operated, and if it is "L", the valve 65 is closed in step 124 as described above, and the blower 45 is operated.
stop. That is, when it is necessary to cool the refrigerator compartment 38, the valve 65 is opened, the compressor 62 is operated as described above, the refrigerant is flowed to the refrigerator compartment cooler 44, and the blower ja 45 is operated to cool the refrigerator compartment 38 and the ice room. 41, and if cooling is not required, close the valve 65 to prevent refrigerant from flowing into the refrigerator compartment cooler 44, and stop the blower 45.

Next, in step 125, it is determined whether the compressor 62 is in operation, and if it is in operation, it is determined in step 126 whether or not the plug F3 is set, and if it is reset, the same process as in step 102 is performed in step 127, and the comparator When the output of 84 is rHJ, the blower 2o is operated in step 129, and when it is ``L,'' the blower 2o is stopped in step 128.In other words, when the second freezing compartment 15 needs to be cooled, the compressor 2o is operated. 62 and the blower 20 to cool both freezer compartments 14 and 15, and stop the blower 20 when it is not needed.If the flag F3 is set here, the flag F2 is set in steps 101 to 130. Reset step 11
1 to operate the compressor 62. Furthermore, in step 122, the process proceeds to step 123, where the valve 65 is opened and the blower 20 is operated. Further, in step 126, the process directly advances to step 129 to operate the blower 20. That is, when the combus 1 nosser 62 is about to stop from a state where refrigerant is flowing only to the freezer compartment cooler 18, the compressor 62, blower 20, and 45 , the valve 65 is opened to allow the refrigerant to flow into both the coolers 44 and 18, and the
If the flag F3 is reset after the minute has passed, step 1
This forced operation is stopped at steps 10, 124 and 129. Therefore, the liquid level in the accumulator 68 remains at L even after the compressor 62 is stopped, so the above-mentioned refrigerant noise does not occur. The period of this forced operation is determined to be the shortest period so that the refrigerant does not accumulate in the refrigerator compartment cooler 44 and does not cause refrigerant noise and does not adversely affect temperature control. It had no effect.

For example, when a large amount of food is put into both freezer compartments 14 or 15, the heat load increases, and the temperature T of the second freezer compartment 15 decreases.
If I rises abnormally and exceeds the temperature C which is -12°C, the output of the converter 88 becomes rH, so the microcomputer 71 proceeds from step 118 to step 121, and if flags F4 and F3 have been reset, step 121 and 122, proceeding to step 124. That is, when the temperature of the second freezer compartment 15 rises abnormally, the valve 65 is closed and the refrigerant flows only through the freezer compartment cooler 18 to cool both freezer compartments 14 and 15, regardless of the output of the converter 76. The increased capacity achieves rapid freezing of input food and prevents food already stored from thawing.

Here, the flag F4 is set when the refrigerator-freezer 1 is powered on, and if the flag F4 is set, the process proceeds from step 121 to step 120, and the above-mentioned operation at abnormal temperature is not performed. Therefore, during the so-called pull-down after installing the refrigerator-freezer 1, even if the temperature of the second freezer compartment 15 is high, both coolers 4
4. and 18 by flowing refrigerant into each chamber 14, 15, 38.4
Perform cooling as described in step 1. Also, this flag F4 is the second freezer compartment 1.
When the temperature T1 of No. 5 falls below C, the process proceeds from step 118 to step 119 and is reset.

In addition, in the examples, the present invention was applied to a so-called refrigerator-freezer, but
For example, you can cool a single storage room with two coolers and choose whether to flow the refrigerant into both or only one.
It is also effective for selectively controlling cooling capacity.

<G> Effects of the Invention According to the present invention, it is possible to selectively control whether the refrigerant flows to both the first cooler and the second cooler or only to the second cooler, and In a compressor equipped with a refrigerant reservoir, when the compressor attempts to stop from a state in which refrigerant is flowing only to the second cooler, the refrigerant flows to both coolers before stopping, so the compressor It is possible to reduce the amount of refrigerant that collects in the refrigerant reservoir during the stoppage of the refrigerant, thereby preventing the generation of refrigerant noise in the refrigerant reservoir. Furthermore, since a normal refrigerant reservoir can be used, the gas-liquid refrigerant separation function is not impaired.

[Brief explanation of drawings]

Figure 1! Fig. 2 is a front view of the refrigerator-freezer, with some doors removed, Fig. 3 is a sectional view taken along line A-A in Fig. 2, Fig. 4 is a refrigerant circuit diagram, and Fig. 5 is a refrigerant diagram. Longitudinal cross-sectional view of the liquid reservoir,
FIG. 6 is an electric circuit diagram of the control device, and FIGS. 7 and 8 are flow charts showing software of the microcomputer. 1... Freezer-refrigerator, 14.15... First and second freezer compartments, 18... Freezer compartment cooler, 38.
...Refrigerating room, 44...Refrigerating room cooler, 62.
...Compressor, 64...Capacitor, 6
5...Solenoid valve, 66.67...First and second key~
Pillari tube, 68... Refrigerant reservoir, 70...
·Control device.

Claims (1)

[Claims] 1. Selectively control whether the refrigerant discharged from the compressor and passed through the condenser flows to both the first cooler and the second cooler or only to the second cooler, and also controls the suction of the compressor. In a compressor equipped with a refrigerant liquid reservoir on the side, if the compressor is stopped while the refrigerant is flowing only to the second cooler, the first cooler and the second cooler are A cooling device characterized by flowing refrigerant into both sides of the container.