JPS61186764A - Refrigeration cycle device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a refrigeration cycle device that can obtain three different cooling temperatures with one compressor, and is suitable for use as, for example, vehicle cooling, refrigeration, and freezing equipment. It is suitable.

[Conventional technology]

The present applicant has developed a refrigerator that achieves both cooling and refrigeration effects by differentiating the evaporation pressures of the evaporator for cooling the passenger compartment and the evaporator for refrigeration, as disclosed in Japanese Unexamined Patent Publication No. 11370/1983. We are proposing a cycle device first.

[Problem that the invention seeks to solve]

The above conventional devices all obtain two temperatures by changing the evaporation pressure in the two evaporators, but in recent years,
There is a tendency for vehicles to be used for leisure activities such as camping, and as a result, there is a demand for refrigerators to be equipped with two evaporators, one for refrigeration and one for freezing, to obtain two different cooling temperatures within the refrigerator. It looks like this.

Therefore, in view of the above points, an object of the present invention is to provide a refrigeration cycle device that can independently set three different cooling temperatures.

[Means for solving problems]

In order to achieve the above object, the present invention provides (a) at least a first suction port, a second suction port, and a third suction port independently, and the refrigerant sucked from each of the three suction ports. (b) a condenser configured to condense the gas refrigerant discharged from the compressor into liquid refrigerant; (c)
) a first pressure reducing device and a first evaporator provided between the refrigerant outlet side of the condenser and the first suction port; (d) a first pressure reducing device and a first evaporator provided between the refrigerant outlet side of the condenser and the second inlet a second pressure reducing device and a second evaporator provided between the suction port; and (e) a third pressure reduction device provided between the refrigerant outlet side of the condenser and the third suction port. (f) the first pressure reducing device, the second pressure reducing device and the third evaporator;
The pressure reducing device is configured such that the evaporation pressure decreases in the order of the first evaporator, the second evaporator, and the third evaporator. a communication mechanism that mixes refrigerant sucked in from the third suction port with high-pressure refrigerant sucked in from the first suction port before compressing the refrigerant; A technical measure is adopted in which the refrigerant is equipped with a communication mechanism that mixes it with the high-pressure refrigerant sucked in from the suction port of the refrigerant.

[Effect]

According to the above technical means, the first to
Refrigerants having different pressures set by the first to third pressure reducing devices can be sucked into the third suction port, so that the evaporation pressure in the evaporator connected downstream of the first to third pressure reducing devices are at different pressures, and the cooling temperatures by each evaporator are different.

In a preferred embodiment of the present invention, the first evaporator performs a cooling function, the second evaporator performs a refrigeration function, and the third evaporator performs a refrigeration function, and the cooling is performed in the order of cooling - cooling and freezing. temperature becomes lower.

In addition, since the compressor is equipped with a communication mechanism that mixes the refrigerant sucked in from the second and third suction ports with the high-pressure refrigerant sucked in from the first suction port before compression, the second and third suction ports mix the refrigerant with high pressure refrigerant sucked in from the first suction port. Although the three suction ports are provided independently, the refrigerant flow rate from the first suction port can be substantially increased, and therefore the cooling capacity (e.g. cooling capacity) in the first evaporator can be increased. can.

I will explain it in detail.

FIG. 1 is a refrigeration cycle diagram showing the configuration of a specific embodiment when used in an automobile refrigeration cycle device that simultaneously cools a vehicle compartment and refrigerates and freezes articles. The compressor 21 is coupled to a drive shaft of an automobile engine (not shown) via an electromagnetic clutch 20.

This compressor 21 is a swash plate type with 10 cylinders, of which 8 cylinders are configured as a compression section 21a for cooling, and 1 cylinder of the remaining 2 cylinders is configured as a compression section 21b for refrigeration,
The remaining one cylinder is configured as a compression section 21c for refrigeration. In this case, each compressor section 21a, 21b of the compressor 21,
21C is independently provided with a cooling inlet 21d, a refrigeration inlet 21e, and a freezing inlet 21''.

Further, the cooling compression section 21a and the refrigeration compression section 21b are communicated with each other by a first communication path 21g, and the cooling compression section 21a is connected to the cooling compression section 21a.
and the refrigeration compression section 21c are communicated with each other by a second communication passage 21h, and the refrigerant (R12) having different pressures sucked from each suction port 21d, 21e, and 21f is communicated with each other before being compressed in each compression section. The refrigerant is communicated with the passage 21g and the communication passage 21h, and after being raised to the pressure of the cooling refrigerant, it is compressed in each compression section and discharged from the common discharge port 21i.

Next, the specific configuration of the compressor 21 will be explained with reference to FIGS. 2 to 7. The compressor 21 of this embodiment has a rotation shaft 210 driven by an automobile engine via an electromagnetic clutch 20. The force is transferred to the piston 2 by the swash plate 211.
The swash plate 211 is keyed to the shaft 210 and rotates together with the shaft 210. Rotation of swash plate 211 is transmitted to piston 212 via shoes 213 and balls 214.

There are five pistons 212, and their surfaces are coated with a resin material such as Teflon. These pistons 212 are arranged to be able to reciprocate in the axial direction within five cylinder bores (one bore 216 is shown in FIG. 3) formed in the cylinder block 215. Both end surfaces of the piston 212 are the cylinder bore 2
16 in cooperation with 10 cylinders (cylinder chambers) 217.2
17a and 217b, and one cylinder 217a (see FIGS. 3 and 4) among these 10 cylinders constitutes the refrigerating compression section 21b in FIG. 1,
Another cylinder 217b (see FIG. 4) constitutes the refrigeration compression section 21C, and the remaining eight cylinders 217 constitute the cooling compression section 21a. cylinder block 2
An axial hole for the shaft zlO and a swash plate chamber 218 that accommodates the swash plate 211 are formed in the center of the cylinder 15, and the swash plate chamber 218 communicates with the cylinder bore 216.

On the other hand, an oil chamber 219, which is normally filled with lubricating oil, is also formed in the lower part of the cylinder block 215.

On both end faces of the cylinder block 215, an annular pulp plate 220 and a suction valve 2 formed of an elastic metal plate are provided.
End plates 222 and 223 are attached via 21,
These parts'215.220.221.222.22
3 are fastened to each other by through bolts 224. Five suction ports 225 are formed in each of the left and right valve plates 220 and 220, and these suction ports 225 can communicate with ten cylinders 217, 217a and 217b via suction valves 221, respectively. ing.

Both end plates 222 and 223 have the same structure, but one end plate 222 has a refrigerating inlet 21e which is a first sub-inlet and a freezing inlet 21 which is a second sub-inlet.
They differ from each other in that the other end plate 223 has a central hole 226 through which the shaft 210 rotatably passes. Both end plates 222 and 223 have a dish-like shape, and approximately circular partition walls 227 and 222 are provided on their inner surfaces, respectively.
8 are provided to protrude in the axial direction, and the inside of the partition walls 227.228 serves as a discharge chamber 229, and the partition walls 227.
A suction chamber 231 is formed between 228 and the outer peripheral wall of each end surface 222,223. The end plate 222 is a partition wall 227
It has separate partition walls 233 and 240, and this partition wall 2
It also differs from the end plate 223 in that the sub-suction chamber 234 for refrigeration and the sub-suction chamber 241 for freezing are partitioned from the suction chamber 231 by 33.240 (see FIG. 4). The refrigeration suction port 21e is opened in the refrigeration sub-suction chamber 234, and the freezing suction port 21f is opened in the freezing sub-suction chamber 241, respectively. The auxiliary suction chambers 234, 241 communicate with the cylinders 217a, 217b via suction ports 225 corresponding to the cylinders 217a, 217b, respectively, while the suction chamber 231 communicates with all remaining cylinders 217. The left and right valve plates 220, 220 are provided with five discharge boats 235 corresponding to the five cylinders, and these discharge boats 235 are opened and closed by discharge valves (not shown), and when they are opened, the discharge chamber 229 is filled. Communicate. This discharge chamber 229 communicates with the discharge port 21i of FIGS. 1 and 2 via a passage 236 of FIG. 4.

As is clear from the above explanation, the refrigeration sub-intake chamber 234
One cylinder 217a that can communicate with the refrigeration sub-compression section 21b constitutes the refrigeration sub-compression section 21b, one cylinder 217b that can communicate with the freezing sub-suction chamber 241 constitutes the refrigeration compression section 2IC, and the other 8 The cylinders 217 are the main compression section 2 for cooling.
1a. Cooling inlet 21 which is the main inlet
d is the cylinder block 21 as shown in FIGS. 2 and 3.
5, and communicates with the swash plate chamber 218 by a structure described later. The swash plate chamber 218 communicates with the left and right suction chambers 231 via a passage formed by a gap between the through bolt 224 and the bolt hole 224a. Therefore, the refrigerant flowing into the suction chamber 231 from the swash plate chamber 218 passes through the suction boat 225 and into the cylinders 217a and 217b.
The air is drawn into all cylinders 217 other than the above. On the other hand, the refrigerant flowing into the refrigeration sub-suction chamber 234 from the refrigeration suction port 21e passes through the suction boat 225 corresponding to the cylinder 217a, that is, the refrigeration sub-compression section 21b.
is inhaled. Similarly, the refrigerant flowing into the freezing sub-suction chamber 241 from the freezing suction port 21' passes through the suction boat 225 corresponding to the cylinder 217b, and then enters the cylinder 217b.
b, that is, it is sucked into the refrigeration sub-compression section 21C.

In order to communicate the cooling inlet 21d and the swash plate chamber 218, a communication groove 237 is formed on the inner surface of each cylinder bore 216 at the axial center of the cylinder bore 216. JI237 is a piston in cylinder bore 216:
It has an annular shape extending in the circumferential direction over a portion around /212. This communication groove 237 directly opens into the swash plate chamber 218, and also communicates with the cooling intake port 21d via a communication hole (not shown).

Note that the discharge port 21i of the compressor 21 is aligned with the cooling intake port 21d as shown in FIG.
15, and this discharge port 21i
communicates with the discharge chambers 229, 229 in the left and right end plates 222, 223 via passages 236 shown in FIGS. 4 and 5.

The refrigeration communication passage 21g shown in FIG.
7a has a circumferential annular groove 238 formed over the entire circumference of the inner circumferential surface of the piston 212.
A plurality of axial communication holes 239 (fifth
It is constantly in communication with the swash plate chamber 218 and the communication groove 237 via the swash plate chamber 218 and the communication groove 237 via the swash plate chamber 218 (see FIG. Therefore, the piston 2 in the cylinder 217a
12 moves in the direction of arrow G in FIG.
After that, the piston 212 reaches near the bottom dead center and the circumferential annular groove 238 is opened to the cylinder 217a. a communication hole 239 through which the low-pressure refrigerant forms a communication path 21g from the groove 237 and the swash plate chamber 218;
It flows into the cylinder 217a through the annular groove 238 and mixes with the low-pressure refrigerant for refrigeration in the cylinder 217a.

Here, the pressure of the low-pressure refrigerant for refrigeration is 1.2 kg/cdG,
Assuming that the pressure of the low-pressure refrigerant for cooling is 2.5 kg/cnfG, when the low-pressure refrigerant for cooling flows into the cylinder 217a through the communication passage 21g and mixes with the low-pressure refrigerant for refrigeration, the refrigerant in the cylinder 217a The pressure in the main compression section 2
The pressure is approximately equal to the pressure at the start of compression of the other cylinder 217 constituting 1a, that is, 2.5 kg/ciG.

The same configuration as above is also adopted for the refrigeration communication passage 21h, and the cylinder 217 that constitutes the refrigeration sub-compression section 21C.
A circumferential annular groove (not shown, the same as the annular groove 238) is formed in the inner peripheral surface of the cylinder 217b over the entire circumference at a position near the bottom dead center of the piston 212 in the cylinder 217b. is constantly connected to the swash plate chamber 218 and the communication groove 237 through a plurality of axial communication holes 242 (FIG. 5) that are formed in the circumferential wall of the cylinder 217b surrounding the piston 212 and spaced apart from each other in the circumferential direction. It's communicating. Therefore, after the piston 212 in the cylinder 217b moves in the direction of arrow G in FIG. When the annular groove in the circumferential direction opens into the cylinder 217b, the low-pressure refrigerant for cooling will flow from the groove 237 and the swash plate chamber 218 to the communication path 2i.
The cylinder 21 passes through the communication hole 242 and the annular groove forming the shape h.
7b and mixes with the low-pressure freezing refrigerant in this cylinder 217b. Here, if the pressure of the low-pressure refrigeration refrigerant is, for example, 0.5 kg/cdG, when the low-pressure cooling refrigerant flows into the cylinder 217b through the communication passage 21h and mixes with the low-pressure refrigeration refrigerant, the cylinder 217b The refrigerant pressure in 217b is equal to the pressure (2.5 kg/
aJG).

From the above, the refrigerating/freezing cylinders 217a, 217
The compression stroke in b starts at almost the same pressure as the compression start pressure of the other cooling cylinder 217, and the compressed refrigerant is discharged into the common discharge chamber 229 and joins with the refrigerant discharged from the other cylinder 217. , and is discharged toward the condenser 22 from the discharge port 21i in FIGS. 1 and 2 via the passage 236.

Therefore, since the refrigerant compression sections 21b and 21c for refrigeration and freezing can be compressed by the pistons from the same pressure state as the cooling compression section 21a, the compressor 21 performs compression from different suction pressure states. It saves power compared to the case.

By the way, the amount of inflow of low-pressure refrigerant for cooling that enters the refrigerating/freezing cylinders 217a and 217b through the aforementioned circumferential annular groove 238 (hereinafter referred to as a "slit" for convenience) (this is referred to as a "slit inflow rate"). ), and the inflow amount of the low-pressure refrigerant for refrigeration/freezing sucked into the cylinders 217a, 217b from the sub-intake ports 21e, 21f for refrigeration/freezing (this is called "volume efficiency") is the width of the slit 238, that is, the cylinder 217a. , 217b is determined by the axial dimension 1 (FIG. 6). FIG. 7 shows the results of various experiments regarding this point. In the experiments, the slits 238 were provided over the entire circumference of the inner surfaces of the cylinders 217a and 217b, and the slit widths l were varied. Here, the width l of the slit 238 with respect to the stroke of the piston 212
The ratio multiplied by 100 is called the "slit aperture ratio",
This slit aperture ratio is plotted on the horizontal axis in FIG.

As is clear from Fig. 7, the volumetric efficiency (inflow amount of low-pressure refrigerant) on the refrigeration side and freezing side decreases as the slit opening ratio increases, so to suppress this decrease, the slit width l should be shorter. On the other hand, the slit inflow rate (slit 238
The inflow amount of low-pressure refrigerant for air conditioning (inflow from (referred to as the "saturation point"). Therefore, during the suction stroke of the cylinders 217a and 217b, the slit 238 is inserted into the cylinder 217 due to the movement of the piston 212.
In order to minimize the decrease in volumetric efficiency caused by opening the slit 238 to the cylinders 217a and 217b and to ensure a sufficient slit inflow rate, it is necessary to
The slit opening ratio is set to be in the range of about 1.6% to 2.4% on the refrigeration side, and in the range of 2.0% to 2.8% on the freezing side. It is clear from FIG. 7 that this is optimal.

The discharge port 21i of the compressor 21 is connected to a condenser 22, as shown in FIG. 1, and the discharge side of the condenser 22 is connected to a receiver 23. A cooling pressure reducing device, in this example a temperature-operated expansion valve 24, and a cooling evaporator 25 connected thereto are provided on the discharge side of the receiver 23. A fan 50 for blowing air is provided. The cooling suction port 2 of the compressor 21 is connected to the refrigerant outlet side of the evaporator 25 by a cooling suction pipe 45.
1d.

On the other hand, the refrigeration cooling unit 26 is provided in parallel with the cooling expansion valve 24 and the evaporator 25, and the refrigeration unit 26 includes a constant pressure expansion valve 27, which is a specific example of a refrigeration pressure reducing device, and It has a refrigerating evaporator 28a connected thereto, and a check valve 29 that allows refrigerant gas to pass in only one direction toward the compressor suction side. The discharge side of the check valve 29 is connected to the refrigeration suction port 21e of the compressor 21 through a refrigeration suction pipe 46. The constant pressure expansion valve 27 opens when the downstream pressure thereof, that is, the pressure inside the refrigerating evaporator 28a, falls below a set pressure, for example, 1.2 kg/cdG.

A refrigeration cooling unit 30 is provided in parallel with the refrigeration cooling unit 26, and this refrigeration cooling unit 30 includes a constant pressure expansion valve 3 which is a specific example of a refrigeration pressure reducing device.
1, a refrigeration evaporator 32a connected to this, and a check valve 33 that allows refrigerant gas to pass only in one direction toward the compressor suction side.
It has The discharge side of this check valve 33 is connected to a pipe 47.
is connected to the refrigeration suction port 21f of the compressor 21. Further, the constant pressure expansion valve 31 has a downstream pressure, that is, a pressure inside the refrigeration evaporator 32a, which is set at a set pressure of, for example, 0.5.
The valve opens when the value falls below kg/cjG.

A solenoid valve 48a is installed in a communication passage 49 that directly connects the cooling suction pipe 45 and the refrigeration suction pipe 46, and when the solenoid valve 48 is opened, the two pipes 45 and 46 are brought into communication. There is.

Similarly, the cooling suction pipe 45 and the freezing suction pipe 47
A solenoid valve 48b is provided in the communication passage 50 that directly connects the two, and when the solenoid valve 48b is opened, the suction pipes 45 and 47 are brought into communication.

Further, the refrigeration evaporator 28a is housed in a cold storage 35 filled with a cold storage agent 28b, and similarly the freezing evaporator 32a is housed in a cold storage 36 filled with a cold storage agent 32b. The detailed structure will be described later.

Next, the electrical circuit of the refrigeration cycle device configured as described above will be described. Reference character 1 denotes an on-vehicle battery, and a cooling control circuit 3 is connected to the battery 1 via a cooling switch 2.

4 is a refrigerator switch, which is connected to the battery 1 via the cooling switch 2;
A refrigerator control circuit 5 is connected to. 6 is a temperature sensor attached to the air blowing side of the cooling evaporator 25;
It consists of a thermistor and is connected to the cooling control circuit 3. In order to prevent the cooling evaporator 25 from freezing, this temperature sensor 6 increases its resistance value when the temperature of the blown air falls below a set temperature.The cooling control circuit 3 determines this change in resistance value, and The compressor 21 is turned off and the compressor 21 is stopped.

Reference numeral 7 denotes a temperature sensor, which is a thermistor, installed to sense the outer surface temperature of the regenerator 35 in which the refrigerating evaporator 28a is housed. Reference numeral 8 denotes a temperature sensor, which is a thermistor, installed to sense the outer surface temperature of the regenerator 36 in which the refrigerating evaporator 32a is housed. Both temperature sensors 7.8 are connected to the refrigerator control circuit 5.

The solenoid valves 48a and 48b are both controlled to open and close by an output signal from the refrigerator control circuit 5, and in this example, both solenoid valves 48a and 48b close when energized and close when energized. A structure that opens when the flow is interrupted is used. In addition, the refrigerator control circuit 5
is based on the temperature detected by the temperature sensor 7.8, the lamp,
A display device 9.10 such as an LED is turned on.

Refrigerating regenerator 3 housing the aforementioned refrigerating evaporator 28a
5 and a freezing regenerator 3 that houses a freezing evaporator 32a.
The refrigerator-freezer 60 according to the present invention is installed in a refrigerator-freezer, and the structure of this refrigerator-freezer will be explained with reference to FIGS. 8 and 9. It is attached by a bracket (not shown) to the upper wall surface of the rear nap seat 72 located behind the nap seat. A door 62 is provided at the front of a case 61 of the refrigerator-freezer 60 so as to be openable and closable. The case 61 of the refrigerator-freezer 60 is a box with a so-called double wall structure using double resin members made of polyethylene or polypropylene, and hard polyurethane is used between the double walls to improve heat insulation. This is done by injecting insulation materials such as door 6
Similarly, the case 2 has a structure combining a double wall structure and a heat insulating material such as hard polyurethane, and is connected to the case 61 by a hinge (not shown) so as to be openable and closable.

The inside of the case of the refrigerator 60 is vertically partitioned by a partition plate 63 made of a hard material with excellent thermal conductivity.

A freezer 64 is installed in the upper left side of the refrigerator interior above the partition plate 63 using a double-layered resin member similar to the case 61, and inside the freezer 64, which is made of a heat insulating member injected with a resin heat insulating material. The freezer 64 has a door 65 that combines a similar double wall structure with a heat insulating material such as hard polyurethane.
are connected by a hinge so that they can be opened and closed. Freezer 64
A refrigerating regenerator 36 made of a material with excellent thermal conductivity and corrosion resistance, such as stainless steel or aluminum, and having an appropriate internal capacity is disposed at the innermost part. Inside the freezing regenerator 36, 400 g of a 19.7% eutectic solution of potassium chloride having a melting point of -11"C is sealed as a refrigerating regenerator 32b to maintain the freezing temperature for a long time, and A refrigeration refrigerant evaporator 32a made of a meandering copper pipe or the like is arranged.A constant pressure expansion valve 31 is provided on the refrigerant inlet side of the refrigeration refrigerant evaporator 32a, and a non-return valve 31 is provided on the refrigerant outlet side. A valve 33 is provided, and a refrigerating regenerator 36 is provided.
The interior of the freezer 64 except for the inside of the freezer 64 is partitioned into upper and lower parts by a partition plate 66, and the space divided into the upper and lower parts is used as a space for storing the object A to be frozen. On the other hand, the refrigerating regenerator 36 is located at the far right side of the chamber above the partition plate 63.
Similarly, a refrigerating regenerator 35, which is made of a material with excellent thermal conductivity and corrosion resistance and has an appropriate capacity inside, is installed. A refrigeration refrigerant evaporator 28a is installed, which is filled with 1000 g of water and is formed into a meandering shape by bending a pipe or the like. A constant pressure expansion valve 27 is provided on the refrigerant inlet side of the refrigerant evaporator 28a for refrigeration.
A check valve 29 is provided on the refrigerant outlet side. Freezer 6
The inside of the case 61 excluding the refrigerating regenerator 4 and the refrigerating regenerator 35 is used as a space for storing the object B to be refrigerated. Four refrigerant pipes are led out from the inside of the case 61 to the outside, and the solenoid valves 48a and 48b shown in FIG. 1 are installed at appropriate locations outside the case 61.

Next, the operation of this embodiment in the above configuration will be explained. Now, when the cooling switch 2 is turned on while the automobile engine is operating, current flows through the cooling control circuit 3 to the excitation coil of the electromagnetic clutch 20, and the electromagnetic clutch 20 is connected. The driving force of the engine is the compressor 21
The compressor 21 rotates and compresses the refrigerant gas.

In the above state, opening/closing of the refrigerator switch 4 and freezing/unfreezing of the cold storage materials 28b, 32b will be sequentially explained.

First, a case will be described in which the refrigerator switch 4 is closed and both the cold storage materials 28b and 32b are not frozen.

Here, the degree of freezing of the cold storage materials 28b and 32b is determined by the freezing degree of the cold storage materials 28b and 32b.
Experiments have shown that if the surface temperature of 5.36 is below -2°C and -12°C, respectively, freezing is sufficient. A comparator in the control circuit 5 compares and determines the set temperature with the temperature detected by the temperature sensor 7.8 to determine whether or not the cold storage materials 28b, 32b are frozen.

When the cold storage materials 28b and 32b are not frozen, the two solenoid valves 48a and 48b are activated by the output of the comparator.
is energized to keep the t magnetic valves 48a and 48b in a normally closed state.

The refrigerant gas discharged from the compressor 21 is cooled and condensed by the condenser 22, and the liquefied refrigerant is stored in the receiver 23. This liquefied refrigerant is used in a temperature-operated expansion valve 2 for cooling.
4. Constant pressure expansion valve 27 for refrigeration and constant pressure expansion valve 3 for freezing
1, the refrigerant becomes a low-temperature, low-pressure gas-liquid two-phase refrigerant, which is then evaporated in the evaporators 25, 28a and 32a, taking heat from the surroundings. The refrigerant that has passed through the cooling evaporator 25 passes through the pipe 45 and is sucked into the compressor 21 from the cooling suction port 21d. On the other hand, the refrigerant that has passed through the refrigeration evaporator 28a passes through the check valve 29 and piping 46 to the refrigeration inlet 21.
The refrigerant that has passed through the refrigeration evaporator 32a is sucked into the compressor 21 through the refrigeration suction port 21f via the check valve 33 and piping 47. Here, as described above, at the end of the suction stroke, the refrigeration and freezing compression sections 21b and 21C communicate with the cooling compression section 21a through the communication passages 21g and 21h, so that the pressure of the refrigerant that has passed through the cooling evaporator 25 (for example, 2.5 kg/cdG), all cylinders of the compressor 21 compress refrigerant whose pressure is 2.5 kg/cdG. The refrigerant supplied to the refrigeration cooling unit 26 is supplied to the constant pressure expansion valve 27 (set pressure 1.2 kir).
/c+Jc, ), the evaporation pressure becomes 1.2 k+r/aJ C; and the evaporation temperature -10.5°C in the refrigerating evaporator 28a, and the regenerator 28 in the regenerator 35
b is gradually frozen. In addition, the cooling unit 30 for freezing
The refrigerant supplied to
Q. The evaporation temperature becomes -21° C., and the cold storage agent 32b in the cold storage device 36 is gradually frozen. In addition, the cooling evaporator 2
5, due to the action of the expansion valve 24, under normal cooling load, the evaporation pressure is 2.5 kg/cdG and the evaporation temperature is 4°C.

FIG. 1O is a Mollier diagram of the refrigeration cycle according to the present invention, where 90 indicates the evaporation pressure in the cooling evaporator 25, 91 indicates the evaporation pressure in the refrigeration evaporator 28'a, and 92 indicates the evaporation pressure in the refrigeration evaporator 28'a. The evaporation pressure in the vessel 32a is shown.

Next, a case will be described in which the refrigerator switch 4 is closed and only the freezing regenerator 32b is sufficiently frozen, that is, when the outer surface temperature of the freezing regenerator 36 is 112° C. or lower. At this time, the comparator in the control circuit 5 determines the detection signal of the temperature sensor 8 and cuts off the power to the solenoid valve 48b, so that the solenoid valve 48b remains open at all times. Further, the solenoid valve 48a remains closed. Solenoid valve 48b
When the valve is opened, the cooling side refrigerant (pressure is 2.5 kg/aJ
G) flows in, the constant pressure expansion valve 31 for refrigeration closes, and no refrigerant flows into the refrigeration cooling unit 30. on the other hand,
A refrigerant flows into the refrigeration evaporator 28a to freeze the refrigeration cold storage agent 28b. The control circuit 5 also includes the solenoid valve 4.
The completion of freezing of the refrigerating regenerator 32b is indicated by cutting off the power to the refrigerating cold storage agent 32b and turning on the refrigerating display device lO.

Note that since a check valve 33 is disposed downstream of the freezing evaporator 32a, there is no possibility that the refrigerant on the cooling side will pass through the pipe 47 and suddenly increase the pressure inside the freezing evaporator 32a. do not have.

Next, a case will be described where the refrigerator switch 4 is closed and only the refrigerating agent 28b is sufficiently frozen, that is, when the surface temperature of the refrigerating regenerator 35 is 12° C. or lower. At this time, the control circuit 5 cuts off the power to the solenoid valve 48a in response to the detection signal of the temperature sensor 7, and opens the solenoid valve 48a. As a result, the cooling side refrigerant flows into the refrigeration sub-inlet 21e of the compressor 21 via the communication path 49, so the refrigeration constant pressure expansion valve 27 closes, and the refrigerant no longer flows into the refrigeration cooling unit 26. On the other hand, a refrigerant flows through the freezing evaporator 28a to freeze the freezing cold storage agent 32b. When the outer surface temperature of the refrigerating regenerator 35 falls below the set temperature (-2° C.), the control circuit 5 compares and determines the detection signal of the temperature sensor 7 and lights up the refrigerating display device 9.
Displays the completion of freezing of the refrigerating cold storage agent 28b. At this time as well, the check valve 29 allows the refrigerant on the cooling side to flow into the refrigeration evaporator 28.
Prevent backflow into a.

Finally, when the refrigerator switch 4 is closed and both the cold storage agents 28b and 32b are sufficiently frozen, that is, the outer surface temperature of the cold storage cold storage 35 is 12 degrees Celsius or less, and the cold storage for freezing The case will be described when the outer surface temperature of the container 36 is 112° C. or less or when the refrigerator switch 4 is open.

In this case, since there is no need to flow refrigerant to the refrigeration cooling unit 26 and the freezing cooling unit 30, the control circuit 5
In response to the output signal, both solenoid valves 48a and 548b are opened, and the pipe 45 is connected to the pipe 46.4 via the communication path 49.50.
Connects to 7. This allows the refrigerant on the cooling side to flow into the communication path 49.
．． 50, via piping 46.47, refrigeration and freezing inlet 2
1e, 21f to refrigeration compression section 21b1 freezing compression section 2
1C, all cylinders of the compressor 21 can be used for cooling. At this time, check valves 29 and 33 are provided downstream of the refrigeration and freezing evaporators 28a and 32a, respectively, so that the refrigerant gas that has passed through the cooling evaporator 25 flows into the refrigeration and freezing evaporators. It does not flow back into the evaporators 28a, 32a and cause the pressure in the evaporators 28a, 32a to rise rapidly. On the other hand, the constant pressure expansion valve 27.31 has a low pressure side pressure of set pressure 1.2.0.5 kg/co1, respectively.
When the temperature rises above G, it automatically closes and stops the supply of refrigerant.

At this time, the display devices 9 and 10 are both lit, and the cold storage agent 2
Displays the completion of freezing of 8b and 32b.

In addition, in an automobile air conditioner, the compressor 21 is controlled intermittently by various signals as is well known, but when the compressor 21 is stopped due to this intermittent control, the evaporation pressure in the cooling evaporator 25 is gradually increases, but the pressure within the freezing and refrigerating evaporators 28a and 32a does not increase in the same way as above.

As described above, the refrigeration cycle is operated, the cold storage agent 28b,
By freezing 32b, the temperature inside the refrigerator is kept low by the latent heat of fusion even when the refrigeration cycle is stopped, such as when parking, and the contents can be maintained at a low temperature.

Although illustration of the specific configuration of the refrigerator control circuit 5 has been omitted in the above description, it is obvious to those skilled in the art that the control circuit 5 can be easily configured by combining well-known comparators, logic circuits, etc. .

The present invention is not limited to the above-described embodiments, but can be implemented in a wide variety of ways, and representative modifications will be listed below.

(1) When using a swash plate type multi-cylinder compressor 21, the refrigeration and freezing compression sections 21b and 21C are
Of course, the number of cylinders is not limited to one cylinder, and the number of cylinders may be increased as appropriate depending on the capacity required for the refrigerator-freezer.

(2) In addition to the swash plate type multi-cylinder compressor 21 described above, a vane type compressor can also be used.

In that case, if the freezing suction port 21f, the refrigeration suction port 21e, and the cooling suction port 21d are sequentially opened in order of decreasing suction pressure along the rotational direction of the rotor, each compression portion 21c
, 21b, 21a all have the highest suction pressure of 2.5kg/c
It becomes possible to start compressing the refrigerant in a state where the refrigerant reaches dG.

(3) The temperature sensor 7.8 that detects the degree of freezing of the cold storage agents 28b and 32b for freezing and refrigeration may detect the temperature inside the freezer and refrigerator, and the temperature sensor 7.8 may be used instead of a thermistor. A temperature switch using a reed switch or the like may also be used.

(4) As a pressure reducing device on the freezing and refrigeration side, the constant pressure expansion valve 27
．． In addition to 31, an ordinary temperature-operated expansion valve or a combination of a solenoid valve and a fixed throttle can be used.

(5) The cooling control circuit 3 and the refrigerator control circuit 5 may be integrated, or both circuits 3 and 5 may be configured using a microcomputer that performs digital arithmetic processing.

(6) The set pressure of the constant pressure expansion valve 27.31 can be freely changed depending on the temperature at which the inside of the refrigerator is desired to be cooled, the freezing temperature of the cold storage agents 28b and 32b, and the like.

(7) Any material may be used as the regenerators 28b and 32b, and the method is not limited to filling the regenerators 35 and 36 with the regenerators 28b and 32b and immersing the evaporator pipes therein. A structure may be adopted in which a cold storage agent sealed in a thin, easily deformable bag made of resin is used, and this cold storage agent is pressure-bonded to the pipes of the evaporators 28a and 32a.

(8) The evaporators 28a and 32a are not limited to those that cool the cold storage agents 28b and 32b, but can also be applied to those that directly cool the air inside the refrigerator, and in that case, it does not matter whether or not an internal fan is used.

(9) In the refrigeration cycle shown in Fig. 1, the refrigerator side has two cooling units 26 and 30 for refrigeration and freezing, and in parallel with these are a solenoid valve, a constant pressure expansion valve, an evaporator, and a check valve. A cooling unit provided with a valve and its connecting pipe may be further added, and the number of cooling units is not limited at all.

Instead of the αllO solenoid valves 48a and 48b, it is also possible to use an electrically controlled valve that opens and closes the valve body by the displacement of a piezoelectric element, or a motor-operated valve.In short, any electrically controlled valve can be used. Can be used.

aυAlso, in the above-mentioned embodiment, the case where the three functions of air conditioning, refrigeration, and freezing are obtained was explained, but the present invention can also be applied to applications that do not require the cooling function. For example, in a single refrigerator, The present invention can be effectively implemented when three or more different cooling temperatures (evaporation pressures) are set.

〔Effect of the invention〕

As mentioned above, according to the present invention, with a simple refrigeration cycle that commonly uses one compressor and one condenser,
There is an excellent effect that three different cooling temperatures can be obtained.

Moreover, the three first to third suction ports 21d, 21e, 2
1f are provided independently, the high pressure refrigerant from the first suction port 21d is mixed with the refrigerant sucked from the second and third suction ports 21e and 21f before compression. By doing so, the flow rate of refrigerant from the first suction port 21d can be substantially increased, and the cooling capacity (for example, cooling capacity) of the first evaporator can be increased. In other words, even though the second and third evaporators provide a cooling effect (e.g., refrigeration/freezing effect), the cooling capacity (e.g., cooling capacity) of the first evaporator is slightly reduced. I can do it.

[Brief explanation of drawings]

All drawings show embodiments of the present invention, and the first
The figure is a refrigeration cycle diagram of the present invention, including an electric circuit. Figure 2 is a perspective view of the main parts of the compressor 21 in Figure 1;
4 is a partial cross-sectional side view of FIG. 3, FIG. 5 is a sectional view taken along the line A-A in FIG. 3, and FIG. 6 is a cross-sectional view taken along the line B-- 7 is an explanatory diagram of the operation of the communication mechanism of the compressor in the present invention, FIG. 8 is a partial perspective view of the interior of the vehicle illustrating the mounting position of the refrigerator-freezer, and FIG. 9 is an illustration of the refrigerator-freezer being opened. FIG. 10, which is a transparent perspective view in the door state, is a Mollier diagram of the refrigeration cycle. 21...Compressor, 211...Discharge port, 21d...
Cooling inlet (first inlet), 21e... Refrigeration inlet (second inlet), 21f... Freezing inlet (third inlet), 21g, 21h... Communication mechanism, 22.
... Condenser, 24... Cooling pressure reducing device (first pressure reducing device), 25... Cooling evaporator (first evaporator), 27
...Refrigerating pressure reducing device (second pressure reducing device), 28a...
Refrigeration evaporator (second evaporator), 31... Freezing pressure reducing device 4 (third pressure reducing device), 32a... Freezing evaporator (third evaporator). Representative Patent Attorney Takashi OkabeFigure 4Figure 5Figure 6Figure 7Figure 8

Claims (1)

[Claims] (a) At least a first suction port, a second suction port, and a third suction port are independently provided, and the refrigerant sucked from each of the three suction ports is compressed, and one refrigerant is compressed. a compressor configured to discharge from a discharge port; (b) a condenser configured to condense gas refrigerant discharged from the compressor into liquid refrigerant; and (c) a refrigerant outlet of the condenser. (d) a first pressure reducing device and a first evaporator provided between the refrigerant outlet side of the condenser and the second inlet; (e) a third pressure reducing device and a third evaporator provided between the refrigerant outlet side of the condenser and the third suction port; (f) the first pressure reducing device, the second pressure reducing device and the third pressure reducing device;
The pressure reducing device is configured such that the evaporation pressure decreases in the order of the first evaporator, the second evaporator, and the third evaporator; a communication mechanism that mixes the refrigerant sucked in through the third suction port with the high-pressure refrigerant sucked in through the first suction port before compressing the refrigerant; A refrigeration cycle device comprising a communication mechanism that mixes a high-pressure refrigerant sucked in from a first suction port.