JPS5826971A - Refrigerator - 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 The present invention relates to a refrigeration system, and more specifically, a bypass passage is provided in the middle part of the compression process in the cylinder chamber of a compressor and on the suction side of the compressor, and the bypass passage is provided with a bypass passage that can be opened and closed. The refrigeration system is provided with an on-off valve to control the capacity of the pressure 41 machine by opening or closing the on-off valve by applying low pressure or high pressure of the refrigeration equipment to the back chamber of the opening 1 valve. It is related to the device.

In this type of refrigeration system, in response to a decrease in the refrigeration load, the opening/closing valve is opened and the intermediate part of the compression process is communicated with the suction side of the compressor to control the eight edges of the compressor into a small device. An unload control is provided. Therefore, when the expansion device constituting a part of the refrigerant circuit is formed by a single capillary tube, the amount of refrigerant flowing through the capillary reach is determined by the pressure difference between the condensing pressure and the firing pressure. If a capillary tube is selected that has a refrigerant flow rate that will give an appropriate degree of superheat during load operation, that is, so-called full load operation, the pressure difference will be large even during unload operation (because it does not change) An amount of refrigerant greater than the required amount flows through the capillary tube, and the evaporation pressure increases.
As a result, there are problems in that the heat exchange efficiency of the heat exchanger decreases and failures occur due to the inflow of liquid refrigerant into the compressor. In addition, if a capillary tube is selected that has a refrigerant flow rate that provides the appropriate degree of superheat during the unload operation, only the amount of refrigerant that is less than the amount of refrigerant required for the proper operation will flow through the capillary tube during the full load operation. There was a problem in that the evaporation pressure decreased and the degree of superheating increased, resulting in poor heat exchange in the evaporator and a decrease in refrigerating capacity.Therefore, as a measure to prevent this problem, two expansion devices were installed. It is formed by interposing capillary tubes in parallel, and both are used during the full load operation, and one is used during the unload operation, so that the refrigerant can be controlled in accordance with the refrigeration load. Conceivable. However, by doing so, the capacity of the compressor can be controlled by using a solenoid valve that opens and closes the on-off valve and a control valve that allows or disables the refrigerant to flow into one of the two capillary tubes. Two valves are required, the number of parts increases, the refrigerant circuit becomes complicated, and the control system that controls both valves becomes complicated.There are many failure points throughout the system, making it unreliable and uneconomical. There was a problem.

Non-invention is to solve the following problems.The purpose is to solve the following problems by simply using a control valve such as a solenoid valve in 1.A. opening/closing control,
It is an object of the present invention to provide a refrigeration system that can reliably perform pressure reduction control of refrigerant using a capillary tube without malfunction, and can reliably perform capacity control and capacity reduction in response to fluctuations in refrigeration load. The refrigerant circuit has a refrigerant circuit in which a compressor, a condenser, an expansion device, and an evaporator are sequentially connected, and a bypass passage is provided at an intermediate part of the compression process in the cylinder chamber of the compressor and at the suction side of the compressor, and the bypass passage To,
An on-off valve that opens and closes the bypass passage is provided, and low pressure or high pressure of a refrigeration system is applied to a rear chamber of the on-off valve to open or close the on-off valve to control the capacity of the compressor. In the refrigeration system, the expansion device is formed by interposing a first capillary reach tube and a second capillary reach tube in parallel, and one control valve is provided on the inlet side of the second capillary reach tube, and the expansion device is formed by interposing a first capillary reach tube and a second capillary reach tube in parallel. One side of a communication pipe communicating with the back chamber of the on-off valve is connected between the control valve and the second capillary reach tube, and by opening or closing the control valve, the high pressure of the refrigeration equipment is transferred to the back chamber. Alternatively, the low pressure may be selectively applied, and both capillary tubes or the first capillary reach tube may be selectively used as an expansion device.

Hereinafter, embodiments of the refrigeration system of the present invention will be described with reference to the drawings.

What is shown in FIG. 1 is a schematic representation of the refrigeration system of the present invention. In FIG. A refrigerant circuit (61) is connected in which a condenser (2), an expansion device (3), and an evaporator (41) are connected in series, and the discharged gas is condensed and liquefied in the condenser (21). The pressure is reduced at 31, and then the evaporator is evaporated at 41, and then the compressor (
1) forms a refrigerant circuit that is sucked into the refrigerant.

As shown in FIG. 2, the rotary compressor 11) has a cylindrical body (7a) with both ends connected to an upper cover (7b) and a lower cover (7c).
A housing (7ζ motor (not shown) and a cylinder block (91) are arranged on top and bottom, and the motor drive shaft (81 is placed in a sealed housing) with a cylinder block (91
The cylinder block (91 has a cylinder chamber (91) having a wall surface concentric with the axis of the drive shaft (8). It consists of a cylinder body (11) with a cylinder chamber (lla), a front head (12) and a catcher head (13) that close the cylinder chamber (lla),
The rotor (10), which rotates eccentrically with respect to the drive shaft (81), is housed in the cylinder chamber (lla).

The compressor mountain is of a stationary blade type, and the rotor (10) is connected to the drive shaft (81).
a cam (10a) extending integrally from the cam and having a cylindrical curve;
A roller (10b) that fits around the outer periphery of the cam (10a), and the axis of the cam (10a) is aligned with the cylinder chamber (ll).
The roller (10b) is eccentric to the axis of the roller (10b).
is made equal to the length between the heads (12) and (13), and the outer circumferential surface is brought into contact with the cylinder wall at a location '1'.

The cylinder body (11) is provided with a blade (1) in a guide groove formed in the body (11) as shown in FIG.
4) is slidably attached, a spring (15) is provided on the back of the blade (14), and the tip surface is attached to the roller (10b).
It is pressed into sealing contact with the outer circumferential surface of. In addition, a suction boat (16) and a discharge boat (17) that open into the cylinder chamber (lla) are provided at positions close to each other on both sides of the blade (14), and the discharge boat (1
7), a discharge valve (18) whose one end is supported by the front head (12) is provided at the opening to the housing (7). The suction port (16) has a suction pipe (6a) extending from the evaporator (41) of the refrigerant circuit (6).
A discharge pipe (6b) leading to the condenser (2:) of the refrigerant circuit (61) is connected to the upper lid (7b).

The capacity control mechanism (51) provided in the compressor (1) controls the suction in the cylinder chamber (lla);
T? - An intermediate pressure port (19) is located in the middle of the compression process from the opening position of the boat (16) to the opening position of the discharge boat (17).
) is opened and a valve chamber (20) communicating with the port (19) is provided, and the suction port (16) is opened from the valve chamber (20).
) is provided with a bypass passage (21) communicating with the valve chamber (
20) includes an on-off valve (22) that opens and closes the intermediate pressure port (19) and the bypass passage (21), and the on-off valve (20).
The compressor (1) is equipped with a spring (23) that always biases the compressor (2) in the opening direction, and the on-off valve (22) is opened and closed by controlling the pressure in the back chamber (24) of the on-off valve (22).
The capacity of 1 is controlled to be a small capacity and a full capacity.

Therefore, what is shown in FIG. 1 is the expansion device (3).
is formed by interposing a first capillary reach tube (3a) and a second capillary reach tube (3b) in parallel, and one control valve 1 is provided on the inlet side of the second capillary reach tube (3b). is provided, and the on-off valve (22) is provided between the closed control valve and the second capillary reach tube (3b).
) by connecting one side of the connecting pipe (25) that communicates with the rear chamber (24), and opening the control valve (1) to supply high-pressure refrigerant from the high-pressure liquid pipe (6c) to the rear chamber (24). By communicating with the on-off valve (22) and closing the control valve (1), the back chamber (24) is communicated with the suction side and the on-off valve (22) is opened. .

The control valve is closed when the refrigeration load is in a large load range from full load to a predetermined intermediate load, and closed when the refrigeration load is in a small load range below the predetermined intermediate load. be.

In Fig. 2, (28) is a connecting pipe (29) for connecting the suction pipe (6a) to the suction boat (16), and (30) is a connecting member for connecting the connecting pipe (25). in,
The on-off valve (22) also serves as a stopper when retracting.However, in the above configuration, if the refrigeration load is in the large load range during refrigeration operation,
njJ control valve (■) is held open, the high-pressure refrigerant in the high-pressure liquid pipe (6c) flows through the @1 branch pipe (26) and the communication pipe (25) to the back chamber of the on-off valve (22). (24)
The compressor (1) presses the on-off valve (22) against the urging force of the spring (23) to close the intermediate pressure boat (19), and the compressor (1) performs a compression action during the entire compression process. It will be in the operating state of the Zenkaku-kei. In addition, in this case, the high pressure liquid pipe (6c
) high-pressure refrigerant is supplied to the first capillary reach tube (3a).
The pressure is reduced from this, and the second capillary reach tube (26) and the second branch pipe (27) are
3b), the pressure is also reduced by the second capillary reach tube (3b). From the above, refrigerating operation can be performed reliably in response to the above-mentioned large load.

Further, when the refrigeration load falls to the small shellfish load range, the control valve (1) is switched to the closed state. As a result, the back chamber (24) of the on-off valve (22) is communicated with the suction side, so the on-off valve (22) is pressed by the biasing force of the spring (23) and the intermediate pressure of the intermediate pressure port (19). and retreat. Therefore, the intermediate pressure boat (19) is communicated with the suction boat (16) via the bypass passage (21), and the compressor +11 is a small compressor that performs a partial compression action after the intermediate pressure boat (19) in the compression process. The capacity is in operation. Further, in this case, the pressure of the high-pressure refrigerant in the high-pressure liquid pipe (6C) is reduced only by the first capillary reach tube (3a), and the amount of circulating refrigerant is derived. As a result of the above, refrigerating operation can be performed reliably in response to the small load.

As described above, according to this embodiment, by simply controlling the opening and closing of the expansion device (even if a capillary tube is used for 31, the one control valve (1)), without using a complicated control device. Large-capacity and small-capacity refrigeration operations can always be performed efficiently and reliably depending on the size of the load.

Moreover, in operating the refrigeration equipment as described above,
When stopping the outside of the compressor (1), the control valve ■
), the on-off valve (22) is automatically opened by the action of a spring, and the bypass passage (21) is closed.
Since the opening of the valve opens, the pressure between high and low pressure is quickly equalized, and again without using a complicated control device, one
Pressure equalization can also be performed by controlling the two control valves (1).In addition, by closing the control valve for a certain period of time during startup and reducing the startup load applied to the motor (81), the startup can be started easily with less startup current. It can be done.

Furthermore, in the refrigerant circuit shown in FIG. 1, the one shown in FIG. By connecting one side to the connecting pipe (25), when the load is large, the control valve (2) is opened and a portion of the high-pressure liquid refrigerant flows through the connecting pipe (25) and the other side to the connecting pipe (25). Flows into the third cow Yabira reach tube via the auxiliary communication pipe (32),
The pressure is reduced by the third capillary reach tube to compress am
The exhaust gas is injected into the suction bow (16) of the compressor (1) and maintains the cylinder block (9) of the compressor (1) and motor 18+ at an appropriate temperature without overheating the discharge gas.
Note that the embodiment shown in Fig. 3 is a model in which the temperature of the discharged gas and the coil temperature of the motor 18) rise excessively when the control valve ①) is opened and the motor 18) is operated at full load. It is applied to compressors.

In the embodiments shown in FIGS. 1 to 3, the first capillary reach tube (3a) has a plurality of capillary tubes formed in series or in parallel so as to have the same depressurizing ability. It includes.

The refrigeration system of the present invention described above is of a heat pump type,
Air conditioning can be applied to equipment that cools and heats the target area.

As described above, the present invention forms the expansion device fil +31 by interposing the first +cabinary reach tube (3a) and the second capillary reach tube (3b) in parallel, 3b), and a communication pipe communicating with the back chamber (24) of the on-off valve (22) is provided between the control valve IVI and the second capillary reach tube (3b). (25), and by opening or closing the control valve (1), the high pressure or low pressure of the refrigeration system is selectively applied to the back chamber (24), and both the capillary reach and Bu (3a) (3
b) Or, by selectively operating the first capillary reach tube (3a) as an expansion device, one control valve IVI can be opened and closed to respond to fluctuations in the refrigeration load.
It is possible to provide a refrigeration system with a simple structure and high reliability, which can reliably perform both the capacity control by the compressor (11) and the pressure reduction control of the refrigerant by the capillary tubes (3a) and (3b) without malfunction.

[Brief explanation of drawings]

Fig. jJ1 is a refrigerant circuit diagram showing an embodiment of the present invention, Fig. 2 is a longitudinal sectional view of a rotary compressor, and Fig. 3 is a refrigerant path diagram showing another embodiment. (1)...Compressor, (2)...Condenser, (31...Expansion device, (3a)...
1st capillary reach tube, (3b)...2nd
Beef Yabirari Yubu, (4)...Evaporator, (
lla)...Cylinder chamber, (21)...
・Bypass passage, (22)...On-off valve, (24
)... Back chamber, (25)... Communication pipe,
■1... Control valves and above Patent applicant Daikin Industries, Ltd. 1 Figure 1el14 1) Figure 3 + 1) 14 1 piece

Claims (1)

[Claims] 111 Compressor (1), condenser (2), expansion device (3
), an evaporator (4) connected in sequence, and a bypass passage ( 21), and the bypass passage (21) is provided with an on-off valve (22) for opening and closing the bypass passage (21),
The on-off valve (22) is opened or closed by applying low pressure or high pressure of the refrigeration system to the back chamber (24) of the on-off valve (22), thereby controlling each company of the compressor (1). In the refrigeration device, the expansion device (3)
is formed by interposing a first capillary reach tube (3a) and a second capillary reach tube (3b) in parallel, and one control valve (2) is provided on the inlet side of the second capillary reach tube (3b). , an 11:1 opening/closing valve (22
) by connecting one side of the communication pipe (25) that communicates with the rear chamber (24) and opening or closing the pressure valve IVI, the pressure of the refrigeration system or low pressure can be supplied to the rear chamber (24). In addition to selectively acting on both capillary tubes (
3a) (3b) or first capillary reach tube (3a)
A refrigeration device characterized in that the refrigeration device selectively acts as an expansion device.