JP2007085706A - Refrigerating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerating device capable of cooling a compressor heated by the operation of the compressor by providing an injection circuit, and improving refrigerating capacity and COP by being constituted to lower a temperature of a refrigerant flowing into an evaporator by utilizing the injection circuit. <P>SOLUTION: In this refrigerating device 1 comprising a refrigerating circuit formed by successively and circularly connecting the compressor 2, a condenser 4, a liquid receiver 5, a pressure reducing device 7 and an evaporator 8, and provided with a first injection circuit K10 comprising an opening/closing valve 10 and a refrigerant expansion adjusting means 9 for supplying a part of the liquid refrigerant to the compressor to cool the same, in the refrigerating circuit from the condenser 4 to the pressure reducing device 7, heat is exchanged between piping H5 of the first injection circuit K10 behind an installation position of the opening/closing valve 10 and the refrigerant expansion adjusting means 9, and piping H3 at an outlet side of liquid receiver 5, and the opening/closing valve 10 and the refrigerant expansion adjusting means 9 are controlled to lower the temperature of the refrigerant flowing into the evaporator 8. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a refrigeration apparatus configured to cool a compressor by a liquid injection method, for example.

  In the conventional refrigeration apparatus 60, for example, as shown in FIG. 8, the high-temperature and high-pressure refrigerant discharged from the compressor 50 flows into the condenser 51 through the discharge side pipe H11 and is condensed there, and then passes through the pipe H12. It is stored in a liquid receiver (liquid reservoir) 52. The liquid refrigerant stored in the liquid receiver 52 flows out from the pipe H13 and is decompressed by the expansion valve 53, and then flows into the evaporator 54 and evaporates. The refrigeration apparatus 60 exhibits a cooling action by the endothermic action generated at this time. And the refrigerant | coolant which came out of the evaporator 54 performs the circulation which returns to the compressor 50 from the suction side piping H14.

Further, a part of the liquid refrigerant stored in the liquid receiver 52 is guided to the injection circuit K10 by the pipe H15, decompressed through the electromagnetic valve SV (electric on-off valve) 10 and the flow control valve V10, and then compressed. It returns to the intermediate pressure part of the machine 50. In this case, a predetermined amount of refrigerant is sealed in the temperature sensing tube 55 and is connected to the flow rate control valve V <b> 10 via the capillary tube 56. The valve opening degree of the flow control valve V10 is controlled as the temperature on the discharge side of the compressor 50 detected by the temperature sensing cylinder 55 increases. And cooling of the compressor 50 which raised the temperature by the operation | movement by evaporating in the compressor 50 was performed (refer patent document 1).
JP 7-127925 A

  However, the refrigeration apparatus provided with the conventional injection circuit has room for improvement with respect to the refrigeration capacity and the COP.

  The purpose of the present invention is to provide an injection circuit to cool the compressor whose temperature has risen due to the operation of the compressor, and to cool the injection circuit by exchanging heat with the piping on the outlet side of the liquid receiver and to flow into the evaporator It is intended to provide a refrigeration apparatus that is configured to lower the temperature of the refrigerant to be improved, improve the refrigeration capacity, and increase the COP.

In order to solve the above problems, a refrigeration apparatus according to claim 1 of the present invention includes a refrigeration circuit in which a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are sequentially connected in an annular fashion, and the decompression is performed from the condenser. In a refrigeration apparatus provided with a first injection circuit having an on-off valve and a refrigerant expansion adjusting means for supplying a part of the liquid refrigerant to the compressor and cooling the refrigeration circuit up to the apparatus,
The piping of the first injection circuit after the installation position of the on-off valve and the refrigerant expansion adjusting means is heat-exchanged with the pipe on the outlet side of the liquid receiver, and the on-off valve and the refrigerant expansion adjusting means are controlled to control the evaporation. The temperature of the refrigerant flowing into the vessel is reduced.

The refrigeration apparatus according to claim 2 of the present invention includes a refrigeration circuit in which a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are sequentially connected in an annular manner, and a liquid is provided in the refrigeration circuit from the condenser to the decompression device. A first injection circuit having an on-off valve and a refrigerant expansion adjusting means for supplying a part of the refrigerant to the compressor for cooling is provided, and a second injection circuit having an on-off valve and a refrigerant expansion adjusting means is provided in the first In a refrigeration system provided in parallel with one injection circuit,
Heat exchange is performed between the piping of the first injection circuit or the piping of the second injection circuit after the installation position of the on-off valve and the refrigerant expansion adjusting means with the piping on the outlet side of the liquid receiver, and the on-off valve and the refrigerant expansion The adjusting means is controlled so as to reduce the temperature of the refrigerant flowing into the evaporator.

  The refrigeration apparatus according to claim 3 of the present invention is the refrigeration apparatus according to claim 1 or 2, wherein the pipe from the condenser to the liquid receiver, the liquid refrigerant reservoir in the liquid receiver or the receiver. One end of the pipe of the injection circuit is connected to the pipe from the liquid vessel to the pressure reducing device.

  A refrigeration apparatus according to a fourth aspect of the present invention is the refrigeration apparatus according to any one of the first to third aspects, wherein the refrigerant expansion adjusting means is a mechanical refrigerant expansion adjusting means or an electric refrigerant expansion adjusting means. It is characterized by that.

  The refrigeration apparatus according to claim 5 of the present invention is the refrigeration apparatus according to any one of claims 1 to 4, wherein the refrigerant temperature or refrigerant overheat of the first injection circuit or the second injection circuit after heat exchange. The on-off valve and / or the refrigerant expansion adjusting means are controlled according to the degree.

  The refrigeration apparatus according to claim 6 of the present invention is the refrigeration apparatus according to any one of claims 1 to 5, wherein the refrigerant flows in the injection circuit for heat exchange and the piping on the outlet side of the receiver. It is characterized in that the flow direction of the refrigerant is counterflow.

  The refrigeration apparatus according to a seventh aspect of the present invention is the refrigeration apparatus according to any one of the first to sixth aspects, wherein the on-off valve and / or refrigerant expansion is performed depending on a compressor discharge refrigerant temperature or a compressor discharge refrigerant superheat degree. The adjusting means is configured to be controlled.

The refrigeration apparatus according to claim 1 of the present invention includes a refrigeration circuit in which a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are sequentially connected in an annular manner, and a liquid is provided in the refrigeration circuit from the condenser to the decompression device. In the refrigeration apparatus provided with the first injection circuit including the on-off valve and the refrigerant expansion adjusting means for supplying a part of the refrigerant to the compressor for cooling, the refrigeration apparatus is provided after the installation position of the on-off valve and the refrigerant expansion adjusting means. The pipe of the first injection circuit is exchanged with the pipe on the outlet side of the liquid receiver, and the temperature of the refrigerant flowing into the evaporator is lowered by controlling the on-off valve and the refrigerant expansion adjusting means. It is characterized by that,
The first injection circuit is provided to cool the compressor whose temperature has increased due to the operation of the compressor, and the piping of the first injection circuit is heat-exchanged with the piping on the outlet side of the receiver, so that the outlet of the receiver Since the refrigerant in the side pipe is cooled to lower the temperature of the refrigerant flowing into the evaporator, the refrigerating capacity is improved, the COP is increased, and the reliability can be improved. .

The refrigeration apparatus according to claim 2 of the present invention includes a refrigeration circuit in which a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are sequentially connected in an annular manner, and a liquid is provided in the refrigeration circuit from the condenser to the decompression device. A first injection circuit having an on-off valve and a refrigerant expansion adjusting means for supplying a part of the refrigerant to the compressor for cooling is provided, and a second injection circuit having an on-off valve and a refrigerant expansion adjusting means is provided in the first In the refrigeration apparatus provided in parallel with the one injection circuit, the pipe of the first injection circuit or the pipe of the second injection circuit after the installation position of the on-off valve and the refrigerant expansion adjusting means is connected to the outlet side of the receiver. Heat exchange with piping, and control of the on-off valve and refrigerant expansion adjusting means to reduce the temperature of the refrigerant flowing into the evaporator Which is characterized,
The first and second injection circuits are provided to cool the compressor whose temperature has increased due to the operation of the compressor, and the first injection circuit pipe or the second injection circuit pipe is connected to the outlet side pipe of the receiver. Heat exchange is performed to cool the refrigerant in the pipe on the outlet side of the receiver and to reduce the temperature of the refrigerant flowing into the evaporator. This improves the refrigeration capacity, increases COP, and compresses the refrigerant. When the load on the compressor is large, the on-off valves and / or refrigerant expansion adjusting means of the first and second injection circuits are controlled to give priority to cooling of the compressor, and when the load is small, the on the outlet side of the receiver The cooling of the refrigerant in the piping can be prioritized, and the compressor can be reliably cooled using both circuits in accordance with the load of the compressor, so that the reliability can be improved.

The refrigeration apparatus according to claim 3 of the present invention is the refrigeration apparatus according to claim 1 or 2, wherein the pipe from the condenser to the liquid receiver, the liquid refrigerant reservoir in the liquid receiver or the receiver. One end of the pipe of the injection circuit is connected to the pipe from the liquid container to the pressure reducing device,
There is a further remarkable effect that a part of the liquid refrigerant can be easily introduced into the injection circuit.

A refrigeration apparatus according to a fourth aspect of the present invention is the refrigeration apparatus according to any one of the first to third aspects, wherein the refrigerant expansion adjusting means is a mechanical refrigerant expansion adjusting means or an electric refrigerant expansion adjusting means. It is characterized by that,
The mechanical refrigerant expansion adjusting means or the electric refrigerant expansion adjusting means has a further remarkable effect that it has a simple structure and high reliability, and is easily available and inexpensive.

The refrigeration apparatus according to claim 5 of the present invention is the refrigeration apparatus according to any one of claims 1 to 4, wherein the refrigerant temperature or refrigerant overheat of the first injection circuit or the second injection circuit after heat exchange. It is configured to control the on-off valve and / or the refrigerant expansion adjusting means depending on the degree,
By setting and controlling an appropriate control value of the refrigerant temperature or the degree of refrigerant superheat according to the temperature rise due to the operation of the compressor, the compressor can be reliably cooled and the reliability can be further improved. There is an effect.

The refrigeration apparatus according to claim 6 of the present invention is the refrigeration apparatus according to any one of claims 1 to 5, wherein the refrigerant flows in the injection circuit for heat exchange and the piping on the outlet side of the receiver. It is characterized in that the flow direction of the refrigerant in the counterflow is,
In the present invention, the flow direction of the refrigerant in the injection circuit for heat exchange and the flow direction of the refrigerant in the pipe on the outlet side of the evaporator may be parallel flow, but heat exchange is achieved by using a counter flow. There is a further remarkable effect that the efficiency can be further improved.

The refrigeration apparatus according to a seventh aspect of the present invention is the refrigeration apparatus according to any one of the first to sixth aspects, wherein the on-off valve and / or refrigerant expansion is performed depending on a compressor discharge refrigerant temperature or a compressor discharge refrigerant superheat degree. It is characterized by being configured to control the adjusting means,
Reliable and accurate control of refrigerant temperature and refrigerant pressure with accurate on / off control of the on-off valve and refrigerant volume control using refrigerant expansion control means and refrigerant expansion control according to temperature rise due to compressor operation. There is a further remarkable effect that the property is improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(1) First embodiment:
FIG. 1 is an explanatory diagram showing an embodiment of a refrigeration circuit and a first injection circuit of a refrigeration apparatus according to the present invention.
FIG. 2 is an enlarged sectional explanatory view of the compressor of the refrigeration apparatus of the present invention.
In FIG. 1, 2 is a scroll type compressor, 3 is an oil separator, 4 is a condenser, 5 is a liquid receiver, 6 is an electromagnetic valve, 7 is an expansion valve as a pressure reducing device, and 8 is an evaporator. Are connected in an annular fashion by pipes H1, H2, H3, and H4 to constitute a refrigeration circuit of the refrigeration apparatus 1.

  In the refrigeration apparatus 1 of the present invention shown in FIG. 1, the high-temperature and high-pressure refrigerant discharged from the compressor 2 flows into the oil separator 3 through the discharge-side pipe H1, and flows into the condenser 4 after the oil is separated. Then, after being condensed there, it is stored in the liquid receiver (liquid reservoir) 5 through the pipe H2. The liquid refrigerant stored in the liquid receiver 5 flows out from the pipe H3, and after being cooled by heat exchange in the heat exchanger 11 and the pipe H5 of the first injection circuit K10 as described below, the liquid refrigerant passes through the solenoid valve 6. After being depressurized by the expansion valve 7, it flows into the evaporator 8 and evaporates. The refrigeration apparatus 1 exhibits a cooling action by the endothermic action generated at this time. And the refrigerant | coolant in the suction side piping H4 which came out of the evaporator 8 returns to the compressor 2 through the piping H4, and is circulated and used.

  That is, a part of the liquid refrigerant stored in the liquid refrigerant storage section 5-1 in the liquid receiver 5 is supplied to the refrigerant expansion adjusting means 9 (for example, a capillary tube, an expansion valve) and the on-off valve 10 (for example, the pipe H5). The first injection circuit K10 having a solenoid valve or the like is led through the refrigerant expansion adjusting means 9 to be decompressed to a low temperature, and the flow rate is controlled. Then, the pipe H5 of the first injection circuit K10 after the installation position of the refrigerant expansion adjusting means 9 and the on-off valve 10 is heat-exchanged in the heat exchanger 11 with the pipe H3 on the outlet side of the liquid receiver 5, and the refrigerant in the pipe H3 is To be cooled. The heat exchanged pipe H5 communicates with the intermediate pressure part 23A of the refrigerant compression chamber 23 in the scroll compression part 21 of the compressor 2 shown in FIG. 2, and the refrigerant of the compressor 2 is injected by the refrigerant injected into the intermediate pressure part 23A. Cooling takes place.

  As shown in FIG. 2, the compressor 2 includes a sealed cylindrical container 30, a drive motor 22, and a scroll compression unit 21. The container 30 is composed of a main body 30A, a bottom lid 30C, and an upper lid 30B, and the peripheral portions 26A and 26B are assembled by argon welding between the main body 30A, the bottom lid 30C, and the upper lid 30B.

  The container 30 is provided with a refrigerant suction port P4, a refrigerant discharge port P1, and an injection suction port P5. A pipe H4 on the outlet side of the evaporator 8 is connected to the refrigerant suction port P4 and is connected to the refrigerant discharge port P1. The discharge side pipe H1 is connected, and the pipe H5 of the first injection circuit K10 is connected to the injection suction port P5.

  In addition, an oil level gauge 24A is provided on the transparent window 24 so that the bottom lid 30C of the container 30 can confirm the amount of oil (not shown) inside. Further, the main body 30A of the container 30 is provided with a power source for the internal drive motor 22 and a terminal 25 such as a temperature detection device (not shown) for detecting the temperature of the compressor 2, and the terminal cover 26 is not shown. It is attached with a mounting band.

  A fixed scroll 27 is provided on the upper lid 30B of the container 30, and the peripheral edge 27A is fixed by shrink fitting as described above. A rocking scroll 28 is disposed opposite to the fixed scroll 27, a refrigerant compression chamber 23 is formed between the fixed scroll 27 and the rocking scroll 28, and rocks in conjunction with the crankshaft 29 of the drive motor 22. The scroll 28 revolves.

  On the other hand, the pipe H2 from the condenser 4 is drawn into the upper part of the receiver 5 and opens there, and the gas-liquid mixed refrigerant condensed in the condenser 4 enters the receiver 5 from the opening of the pipe H2. Inflow. Then, the liquid refrigerant in the refrigerant flowing into the liquid receiver 5 is stored by its own weight in the liquid refrigerant storage section 5-1 in the lower part of the liquid receiver 5, whereby the refrigerant is gas-liquid separated.

  The operation of the refrigeration apparatus 1 of the present invention will be described with the above configuration. When a power switch (not shown) is turned on, commercial power is supplied to the drive motor 22 via the terminal 25. Then, when the drive motor 22 rotates and the swinging scroll 28 of the scroll compression unit 21 starts revolving in conjunction with the crankshaft 29, the refrigerant sucked from the suction side located around the scroll compression unit 21 is It is confined in a half-moon shaped refrigerant compression chamber 23 formed by both scrolls 27 and 28, and its volume is gradually reduced toward the center. As a result, the refrigerant is compressed, and the high-temperature and high-pressure gas refrigerant is discharged from the center of both scrolls 27 and 28 to the discharge-side pipe H1 from the refrigerant discharge port P1.

The discharged high-temperature and high-pressure gas refrigerant enters the condenser 4 through the pipe H <b> 1, and is condensed and liquefied there, and then enters the liquid receiver 5 through the pipe H <b> 2. 1 is temporarily stored. Then, the liquid refrigerant stored in the liquid refrigerant storage section 5-1 at the lower part of the liquid receiver 5 is exchanged with the pipe H5 of the first injection circuit K10 in the heat exchanger 11 through the pipe H3. The refrigerant is cooled. The refrigerant in the pipe H3 cooled in the heat exchanger 11 passes through the pipe H3, is reduced in pressure by the expansion valve 7 through the electromagnetic valve 6, and then flows into the evaporator 8, where it evaporates and vaporizes. The refrigeration apparatus 1 exhibits a cooling capacity by the endothermic effect generated at this time.
The evaporated low-temperature gas refrigerant in the pipe H4 on the outlet side of the evaporator 8 is further sucked into the compressor 2 through the pipe H4.

  The first injection circuit K10 is provided to cool the compressor 2 whose temperature has risen due to the operation of the compressor 2, and the pipe H5 of the first injection circuit K10 is heat-exchanged with the pipe H3 on the outlet side of the liquid receiver 5. Since the refrigerant in the pipe H3 on the outlet side of the liquid receiver 5 is cooled and the temperature of the refrigerant flowing into the evaporator 8 is lowered, the refrigerating capacity is improved, the COP is increased, and the reliability is increased. Can be improved.

  For example, when the refrigerant expansion adjusting means 9 and the on-off valve 10 of the first injection circuit K10 are controlled to cool the refrigerant in the pipe H5 of the first injection circuit K10 to about 5 to 10 ° C., the first injection circuit When heat is not exchanged between the pipe H5 of the K10 and the pipe H3 on the outlet side of the liquid receiver 5, the temperature of the refrigerant in the pipe H3 on the outlet side of the liquid receiver 5 was about 45 ° C., but the first injection circuit When the pipe H5 of K10 is cooled by exchanging heat with the pipe H3 on the outlet side of the liquid receiver 5, the temperature of the refrigerant in the pipe H3 on the outlet side of the liquid receiver 5 is reduced to about 25 ° C., and as a result, Refrigeration capacity is improved and COP is increased.

  On the other hand, the opening / closing valve 10 of the injection circuit K10 opens simultaneously with the start of the compressor 2. When high-temperature and high-pressure gas refrigerant is discharged from the compressor 2, the temperature of the discharge-side pipe H1 rises, and as a result, the refrigerant pressure in the temperature sensing cylinder 55 (not shown) installed in the discharge-side pipe H1 rises. Then, the pressure in the pressure chamber (not shown) in the refrigerant expansion adjusting means 9 rises through the capillary tube 56 (not shown), and the valve opening degree of the refrigerant expansion adjusting means 9 is controlled by the pressure in the pressure chamber, so that the valve is appropriately opened.

The liquid refrigerant in the liquid receiver 5 also flows into the pipe H5 of the injection circuit K10, expands through the refrigerant expansion adjusting means 9, is reduced in pressure, becomes low temperature, and the flow rate is controlled. Then, heat is exchanged between the pipe H5 of the first injection circuit K10 in the pipe H3 on the outlet side of the liquid receiver 5 and the heat exchanger 11, and the refrigerant in the pipe H3 is cooled.
After the heat exchange, the refrigerant in the pipe H <b> 5 of the first injection circuit K <b> 10 is supplied to the intermediate pressure part 23 </ b> A in the middle of the compression in the scroll compression part 21 of the compressor 2 to cool the compressor 2. In this case, the refrigerant pressure in the temperature sensing cylinder 55 (not shown) changes due to the change in the temperature of the discharge side pipe H1 of the compressor 2, thereby adjusting the valve opening amount of the on-off valve 10 and optimizing the temperature of the compressor 2. Adjusted to

  In the first embodiment, the refrigerant temperature or refrigerant superheat degree (refrigerant temperature-refrigerant saturation temperature) at point b of the pipe H5 of the first injection circuit after heat exchange shown in FIG. If the refrigerant temperature or refrigerant superheat degree at point a of the pipe H3 after the detection is detected and the on-off valve 10 and / or the refrigerant expansion adjusting means 9 are thereby controlled, the temperature rise due to the operation of the compressor is facilitated. Accurately capture and cool the compressor properly.

  Further, if the compressor discharge refrigerant temperature or the compressor discharge refrigerant superheat degree is detected and the on-off valve 10 and / or the refrigerant expansion adjusting means 9 are controlled thereby, the on / off control of the on-off valve 10 and the refrigerant expansion are performed. Control of the refrigerant amount and the refrigerant pressure by the refrigerant amount control and the refrigerant expansion control using the adjusting means 9 can be performed accurately and reliably.

  In the first embodiment, an example is shown in which the flow direction of the refrigerant in the pipe H5 of the injection circuit K10 for heat exchange and the flow direction of the refrigerant in the pipe H3 on the outlet side of the liquid receiver 5 are set in parallel flow. However, although not shown, the heat exchange efficiency can be further improved by using a counter flow.

  As an example of the refrigerant expansion adjusting means 9, an example of an electric valve that is an electric refrigerant expansion adjusting means has been described. However, as the refrigerant expansion adjusting means 9, the mechanical expansion valve as described above can be used. As an example of the mechanical expansion valve, an example in which a predetermined amount of refrigerant is sealed in a temperature sensing cylinder 55 as shown in FIG. 8 and connected to the refrigerant expansion adjusting means 9 through a capillary tube 56 can be given. As the temperature on the discharge side of the compressor detected by the temperature sensing cylinder 55 rises, the opening degree of the refrigerant expansion adjusting means 9 is controlled.

  In the said 1st embodiment, although the example of the order of the refrigerant | coolant expansion | swelling adjustment means 9 and the on-off valve 10 from the upstream was shown for the installation order of the refrigerant | coolant expansion adjustment means 9 and the on-off valve 10 in a 1st injection circuit, this order is this. However, the order of the on-off valve 10 and the refrigerant expansion adjusting means 9 may be arranged from the upstream.

(2) Second embodiment:
FIG. 3 is an explanatory view for explaining a refrigeration circuit and a first injection circuit of another refrigeration apparatus of the present invention.
Another refrigeration apparatus 1A of the present invention is the same as the refrigeration apparatus 1 of the present invention shown in FIG. 1 except that one end of the pipe H5 of the first injection circuit K10 is connected to the pipe H2 from the condenser 4 to the receiver 5. It is the same. In addition to being able to easily introduce a part of the liquid refrigerant into the pipe H5 of the first injection circuit K10 branched from the pipe H2, there are the same effects as the refrigeration apparatus 1 of the present invention shown in FIG.

(3) Third embodiment:
FIG. 4 is an explanatory view for explaining a refrigeration circuit and a first injection circuit of another refrigeration apparatus of the present invention.
Another refrigeration apparatus 1B of the present invention is the same as the refrigeration apparatus 1 of the present invention shown in FIG. 1 except that one end of the pipe H5 of the first injection circuit K10 is connected to the pipe H3 from the receiver 5 to the decompression apparatus 7. It is the same. In addition to being able to easily introduce a part of the liquid refrigerant into the pipe H5 of the first injection circuit K10 branched from the pipe H3, the same effects as the refrigeration apparatus 1 of the present invention shown in FIG.

(4) Fourth embodiment:
FIG. 5 is an explanatory diagram for explaining a refrigeration circuit, a first injection circuit, and a second injection circuit of another refrigeration apparatus of the present invention.
As shown in FIG. 5, another refrigeration apparatus 1 </ b> C of the present invention is an on-off valve for supplying a part of the liquid refrigerant from the liquid refrigerant reservoir 5-1 of the liquid receiver 5 to the compressor 2 for cooling. 10 and the first injection circuit K10-1 having the refrigerant expansion adjusting means 9 are provided in the pipe H5, and the second injection circuit K10-2 having the on-off valve 10 and the refrigerant expansion adjusting means 9 is branched from the pipe H5. 1 is provided in parallel with the injection circuit K10-1, and the pipe H5 of the first injection circuit K10-1 after the installation position of the on-off valve 10 and the refrigerant expansion adjusting means 9 is heat exchanged with the pipe H3 on the outlet side of the liquid receiver 5. Then, after controlling both the on-off valves and both refrigerant expansion adjusting means to lower the temperature of the refrigerant in the pipe 3, the pipe H5 after joining both circuits and exchanging heat is compressed as shown in FIG. Machine 2 The refrigeration apparatus shown in FIG. 1 except that the compressor 2 is communicated with the intermediate pressure portion 23A of the refrigerant compression chamber 23 in the compressor compressor 21 and the compressor 2 is cooled by the refrigerant injected into the intermediate pressure portion 23A. It is the same as 1.

The pipe H5 of the first injection circuit K10-1 is heat-exchanged with the pipe H3 on the outlet side of the receiver 5 to cool the refrigerant in the pipe H3 and to reduce the temperature of the refrigerant flowing into the evaporator 8. Therefore, the refrigerating capacity is improved, the COP is increased, and the reliability can be improved.
When the load on the compressor 2 is large, the first injection circuit K10-1 and the second injection circuit K10-2 are preferentially used for cooling the compressor 2, and when the load on the compressor 2 is small, the priority is given. It can be used for cooling the refrigerant flowing into the evaporator 8, and can appropriately cope with the load of the compressor 2.

(5) Fifth embodiment:
FIG. 6 is an explanatory diagram for explaining a refrigeration circuit, a first injection circuit, and a second injection circuit of another refrigeration apparatus of the present invention.
Another refrigeration apparatus 1D of the present invention is such that one end of a pipe H5 connected to the first injection circuit K10-1 and the second injection circuit K10-2 is connected to the pipe H2 from the condenser 4 to the receiver 5. Is the same as the refrigeration apparatus 1C of the present invention shown in FIG. A part of the liquid refrigerant can be easily introduced into the first injection circuit K10-1 and the second injection circuit K10-2 through the pipe H5 branched from the pipe H2, and the refrigeration apparatus 1C of the present invention shown in FIG. The same effect is produced.

(6) Sixth embodiment:
FIG. 7 is an explanatory diagram for explaining a refrigeration circuit, a first injection circuit, and a second injection circuit of another refrigeration apparatus of the present invention.
Another refrigeration apparatus 1E according to the present invention is such that one end of a pipe H5 connected to the first injection circuit K10-1 and the second injection circuit K10-2 is connected to the pipe H3 from the liquid receiver 5 to the decompression device 7. Is the same as the refrigeration apparatus 1C of the present invention shown in FIG. A part of the liquid refrigerant can be easily introduced into the first injection circuit K10-1 and the second injection circuit K10-2 through the pipe H5 branched from the pipe H3, and the refrigeration apparatus 1C of the present invention shown in FIG. The same effect is produced.

  The description of the above embodiment is for explaining the present invention, and does not limit the invention described in the claims or reduce the scope thereof. Moreover, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim.

The refrigeration apparatus of the present invention includes a refrigeration circuit in which a compressor, a condenser, a receiver, a decompression device, and an evaporator are sequentially connected in an annular manner, and a part of the liquid refrigerant is added to the refrigeration circuit from the condenser to the decompression device. In the refrigeration apparatus provided with a first injection circuit having an on-off valve and a refrigerant expansion adjusting means for supplying and cooling to the compressor, the first injection after the installation position of the on-off valve and the refrigerant expansion adjusting means The circuit piping is configured to exchange heat with piping on the outlet side of the receiver, and to control the on-off valve and the refrigerant expansion adjusting means to reduce the temperature of the refrigerant flowing into the evaporator. Is what
The first injection circuit is provided to cool the compressor whose temperature has increased due to the operation of the compressor, and the piping of the first injection circuit is heat-exchanged with the piping on the outlet side of the receiver, so that the outlet of the receiver Since the refrigerant in the side pipe is cooled to lower the temperature of the refrigerant flowing into the evaporator, the refrigerating capacity is improved, the COP is increased, and the reliability can be improved. So the industrial utility value is high.

It is explanatory drawing which shows 1 embodiment of the freezing circuit of the freezing apparatus of this invention, and a 1st injection circuit. It is expansion sectional explanatory drawing of the compressor of the freezing apparatus of this invention. It is explanatory drawing explaining the freezing circuit and 1st injection circuit of the other freezing apparatus of this invention. It is explanatory drawing explaining the freezing circuit and 1st injection circuit of the other freezing apparatus of this invention. It is explanatory drawing explaining the freezing circuit of the other freezing apparatus of this invention, a 1st injection circuit, and a 2nd injection circuit. It is explanatory drawing explaining the freezing circuit of the other freezing apparatus of this invention, a 1st injection circuit, and a 2nd injection circuit. It is explanatory drawing explaining the freezing circuit of the other freezing apparatus of this invention, a 1st injection circuit, and a 2nd injection circuit. It is explanatory drawing explaining the refrigeration circuit and liquid injection circuit of the conventional freezing apparatus.

Explanation of symbols

1, 1A, 1B, 1C, 1D, 1E Refrigeration device 2 Compressor 3 Oil separator 4 Condenser 5 Liquid receiver 5-1 Liquid refrigerant reservoir 6 Electromagnetic valve 7 Expansion valve 8 Evaporators H1, H2, H3, H4, H5 Piping 9 Refrigerant expansion adjusting means 10 On-off valve 11 Heat exchanger K10, K10-1 First injection circuit K10-2 Second injection circuit 23 Refrigerant compression chamber 23A Intermediate pressure part

Claims (7)

A refrigeration circuit in which a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are sequentially connected in an annular manner, and a part of the liquid refrigerant is supplied to the compressor from the condenser to the decompression device. In the refrigeration apparatus provided with the first injection circuit including the on-off valve for cooling and the refrigerant expansion adjusting means,
The piping of the first injection circuit after the installation position of the on-off valve and the refrigerant expansion adjusting means is heat-exchanged with the pipe on the outlet side of the liquid receiver, and the on-off valve and the refrigerant expansion adjusting means are controlled to control the evaporation. A refrigeration apparatus configured to reduce the temperature of the refrigerant flowing into the container. A refrigeration circuit in which a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are sequentially connected in an annular manner, and a part of the liquid refrigerant is supplied to the compressor from the condenser to the decompression device. In the refrigeration apparatus provided with the first injection circuit including the on-off valve and the refrigerant expansion adjusting means for cooling, and the second injection circuit including the on-off valve and the refrigerant expansion adjusting means provided in parallel with the first injection circuit,
Heat exchange is performed between the piping of the first injection circuit or the piping of the second injection circuit after the installation position of the on-off valve and the refrigerant expansion adjusting means with the piping on the outlet side of the liquid receiver, and the on-off valve and the refrigerant expansion A refrigeration apparatus configured to control the adjusting means to reduce the temperature of the refrigerant flowing into the evaporator.   One end of a pipe of the injection circuit is connected to a pipe from the condenser to the liquid receiver, a liquid refrigerant reservoir in the liquid receiver or a pipe from the liquid receiver to the pressure reducing device. Item 3. The refrigeration apparatus according to claim 1 or 2.   4. The refrigeration apparatus according to claim 1, wherein the refrigerant expansion adjusting means is a mechanical refrigerant expansion adjusting means or an electric refrigerant expansion adjusting means.   2. The on-off valve and / or the refrigerant expansion adjusting means are controlled by the refrigerant temperature or the refrigerant superheat degree of the first injection circuit or the second injection circuit after heat exchange. Item 5. The refrigeration apparatus according to any one of Items 4 to 4.   6. The flow direction of the refrigerant in the injection circuit for heat exchange and the flow direction of the refrigerant in the pipe on the outlet side of the receiver are set as counterflows. Refrigeration equipment.   The refrigeration apparatus according to any one of claims 1 to 6, wherein the on-off valve and / or the refrigerant expansion adjusting means are controlled by a compressor discharge refrigerant temperature or a compressor discharge refrigerant superheat degree. .

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