RU2347985C2 - Cooling device - Google Patents

Abstract

FIELD: heating.

SUBSTANCE: present invention pertains to a cooling device. The cooling device has cooling circuit (9) comprising: i) compressor (2), executing the cooling cycle; ii) evaporator (3), absorbing heat energy of the medium being cooled; iii) condenser (4), transmitting heat energy to an external medium; iv) capillary pipe (5), allowing for expansion of the cooling agent coming out of condenser (4), and carrying the cooling agent to evaporator (3); v) valve (6) with electromagnetic control, controlling flow of the cooling agent and located between condenser (4) and capillary pipe (5); vi) bypass line (7), leveling pressure in the sucking and blowing parts of the compressor (2). The cooling circuit (9) also has: i) valve (16) electromagnetically controlled, which prevent reverse flow to evaporator (3) when compressor (2) is not working and which is in the sucking part of the compressor (2); ii) control mechanism (8), which delays opening of electromagnetically controlled valve (16) by a period, which runs from starting the compressor (2) until a limit value of torque is attained.

EFFECT: prevention of migration of cooling agent when the compressor is not working and easier start up of the compressor.

3 cl, 3 dwg

Description

The present invention relates to a cooling device, wherein the device includes a cooling circuit that prevents migration of the refrigerant.

In cooling devices, such as refrigerators and air conditioners, when the compressor is not running, the refrigerant, which is under high pressure inside the condenser, moves to the evaporator, which is under lower pressure; the refrigerant, which reaches the evaporator and has a high temperature, creates an additional load during cooling. This process, leading to the loss of useful work, is called migration of the refrigerant. For this reason, in cooling systems, when the compressor is stopped, the path of the refrigerant, which moves to the evaporator from the condenser, is blocked and thus prevents the migration of the refrigerant, however, unless other precautions are taken, until the pressure between the condenser and the evaporator is not aligned, due to the high pressure difference between the suction and discharge parts of the compressor, a problem arises regarding the compressor starting at the beginning of the working period, that is, after tadii compressor stop. When solving the problem of compressor start-up, even if equilibrium of the pressure medium is reached during start-up, by using, for example, bypass lines provided between the suction and discharge parts of the compressor, an intense flow will be created until, during the initial seconds of the operating period, compressor torque limit value.

In US patents US 5088303 and US 3722228, as well as in European patent EP 0060315 proposed mechanical prevention of migration of the refrigerant through the use of valves.

In US patents US 4735054 and US 4790142 proposed prevention of migration of the refrigerant by using a blocking valve with automatic control in a heat pump operating in two directions, while at the beginning of the operating period, the reverse flow valve is actuated, the pressure between the suction and discharge parts is balanced and thereby facilitating compressor start-up.

US Pat. No. 5,309,728 proposes preventing the migration of a refrigerant in an air conditioner, including a large number of evaporators, within a short period after the equipment stops in the internal circuit, while the compressor is stopped or the compressor is in reverse mode and the pressure is balanced by the bypass lines between capacitor and exhaust lines.

According to European patent application EP 0692687, a solenoid valve is used at the inlet of the capillary tube and thus prevents the refrigerant from migrating, using a control mechanism that sets the time between the operation of the solenoid valve and the compressor.

The objective of the present invention is to provide a cooling device and a method of its operation, which can prevent the migration of the refrigerant occurring when the compressor is stopped, and also improve the start-up of the compressor in the initial period of operation, which occurs immediately after the period of the stopped state.

The specified technical problem is solved in the proposed cooling device containing a cooling circuit, including: i) a compressor that performs a cooling cycle; ii) an evaporator that absorbs the thermal energy of the medium to be cooled; iii) a capacitor that transfers thermal energy to the environment; iv) a capillary tube that expands the refrigerant that leaves the condenser and transfers the refrigerant to the evaporator; v) an electromagnetically controlled valve that controls the flow of the refrigerant between the condenser and the capillary tube; vi) a bypass line balancing the pressure in the suction and discharge parts of the compressor, the cooling circuit according to the invention comprising: i) an electromagnetic valve that prevents backflow to the evaporator when the compressor is idle and which is located in the suction part of the compressor; ii) a control mechanism that delays the opening of the solenoid valve for the period that elapses from the compressor starting up until the torque limit is reached.

Preferably, the cooling circuit also comprises: i) a bypass line that is located between the solenoid valve and the compressor suction part and which allows the refrigerant to flow to the compressor suction part, thereby establishing a pressure balance in the compressor suction and discharge parts.

The cooling circuit may include: i) a bypass line that balances the pressure when the solenoid valve is blocked to prevent refrigerant migration, and which is installed between the suction and discharge parts of the compressor; ii) a solenoid valve that is installed on the bypass line.

A cooling device with a control method designed to achieve the above objectives according to the invention is shown in the accompanying drawings, in which:

figure 1 presents a perspective view of a cooling device;

figure 2 presents a schematic view of a cooling circuit;

figure 3 presents a schematic view of a cooling circuit in an alternative application of the invention.

The elements shown in the drawings are individually numbered as follows:

1 - cooling device;

2 - compressor;

3 - evaporator;

4 - capacitor;

5 - capillary tube;

6, 16, 116 - valve with electromagnetic control;

7, 17 - bypass line;

8 - control mechanism;

9 - cooling circuit.

The cooling circuit (9), which provides a cooling cycle and which is used for cooling devices (1), for example, refrigerators and air conditioners, includes a compressor (2), an evaporator (3) that takes the thermal energy of the environment to be cooled, a condenser (4) that transfers thermal energy to the external environment, a capillary tube (5) that expands the refrigerant that leaves the condenser (4) and transfers the refrigerant to the evaporator (3), preferably a two-way valve (6) with electromagnetic control, which prevents the migration of the refrigerant by blocking the flow when the compressor (2) is stopped, and which is located between the condenser (4) and the capillary tube (5), the valve (16) with electromagnetic control, which prevents the return flow to the evaporator (3) when the compressor (2) is stopped and which is located in the suction part of the compressor (2), a bypass line (7), which is located between the solenoid valve (6) and the suction part of the compressor (2) and the cat The open one allows the flow of the refrigerant, blocked when the compressor (2) is stopped, to the suction part of the compressor (2), while balancing the pressure in the suction and discharge parts of the compressor (2), a control mechanism (8) that controls the operation of the valves (6 , 16) with electromagnetic control and compressor (2) (figure 2).

An electromagnetic-controlled valve (6) allows you to maintain a cooling cycle by directing the flow to the capillary tube during the working period and deflects the flow to the bypass line (7), blocking the flow that passes to the capillary tube (5) with the compressor (2) stopped.

In the method for controlling the cooling device (1), which is the subject of the invention, in the case of a stopped compressor (2), the migration of the refrigerant from the condenser (4) to the evaporator (3) is prevented by closing the outlet of the capillary tube (5) of the valve (6) with electromagnetic control. At the same time, the output of the bypass line (7) of the valve (6) with electromagnetic control is opened and, by deflecting the flow to the suction part of the compressor (2), the pressure between the suction and discharge parts of the compressor (2) is brought into equilibrium. The valve (16) with electromagnetic control, which is located on the suction part of the compressor (2), is closed and prevent backflow to the evaporator (3). When the compressor (2) is in operation, to maintain the cooling cycle, the output of the capillary tube of the valve (6) with electromagnetic control is opened, and the output of the bypass line (7) is blocked. If the valve (16) with electromagnetic control opens synchronously with the period of operation of the compressor (2), the pressure in the suction part of the compressor (2) partially decreases until the limit value of the torque that must be obtained by the compression function after the initial start is reached , and during the stopped state, even if the pressure is balanced, there will be a pressure difference between the two parts of the compressor (2); this pressure difference creates a strong flow during the initial start-up of the compressor (2). In the case of the application constituting the subject of the invention, when the compressor (2) switches from the stopped state to the working period, the opening of the valve (16) with electromagnetic control is delayed by the period that represents the period between the start of the compressor (2) start and the torque limit is reached moment. Therefore, the balanced pressure values maintained when the compressor (2) is stopped will be maintained when the limit value of the torque is reached and at that moment in time when the discharge function of the compressor (2) begins, by the bypass line (7), while the high flow rates provided by the compressor traction (2) during the start-up will be prevented.

In yet another application according to the invention, the cooling circuit (9) includes an electromagnetic valve (6) that prevents the refrigerant from migrating by blocking the flow when the compressor (2) is stopped and which is located between the condenser (4) and the capillary tube (5 ), the valve (16) with electromagnetic control, which prevents the return flow to the evaporator (3) when the compressor (2) is stopped and which is installed on the suction part of the compressor (2), the bypass line (17), which is balanced there is pressure when the valve (6) with electromagnetic control is blocked to prevent migration of the refrigerant, and which is installed between the suction and discharge parts of the compressor (2), the valve (116) with electromagnetic control, which is installed on the bypass line (17), and the mechanism control (8), which controls the operation of valves (6, 16, 116) with electromagnetic control and compressor (2) (figure 3).

With the indicated application of the invention in the case of a stopped compressor (2), as soon as the solenoid valve (6), which is located between the condenser (4) and the capillary tube (5), is blocked, the solenoid valve (116) is located on the bypass line (17), opens and allows the flow to flow in a direction that is opposite to the discharge direction, and thus the pressure will be balanced. A valve (16) with electromagnetic control located on the suction part of the compressor (2), when closed, prevents reverse flow to the evaporator (3). When the compressor (2) is switched to the operating mode to maintain the cooling cycle, the solenoid valve (6), which is located between the capillary tube (5) and the condenser (4), opens, and the solenoid valve (116), which is located on bypass line (17), closes. The opening of the valve (16) with electromagnetic control can be delayed by the control mechanism (8) for the period that elapses from the start of the compressor (2) until the maximum torque value is reached. Therefore, the balanced pressure values, reversed when the compressor (2) is stopped, will be saved by the bypass line (17) until the limit value of torque is reached, and the compressor (2) performs its discharge function, at this will prevent draft by compressor (2) with high flow rates.

In the case of the cooling device (1) and its control method, which are the subject of the invention, migration of the refrigerant which occurs when the compressor (2) is stopped from the condenser (4) to the evaporator (3) and which leads to loss of useful work will be prevented; provided that the refrigerant migration is prevented, the pressure between the suction and discharge parts of the compressor (2) will be equalized, this will allow easier start-up of the compressor (2), and during the start-up, until the torque limit value is reached, traction by compressor (2) with high flow rates will be prevented.

Claims (3)

1. A cooling device (1) comprising a cooling circuit (9) including: i) a compressor (2) performing a cooling cycle; ii) an evaporator (3) that absorbs the thermal energy of the medium to be cooled; iii) a capacitor (4) that transfers thermal energy to the external environment; iv) a capillary tube (5) that expands the refrigerant that leaves the condenser (4) and transfers the refrigerant to the evaporator (3); v) a valve (6) with electromagnetic control that controls the flow of the refrigerant and located between the condenser (4) and the capillary tube (5); vi) a bypass line (7, 17) balancing the pressure in the suction and discharge parts of the compressor (2), characterized in that the cooling circuit (9) contains: i) an electromagnetic control valve (16) that prevents backflow to the evaporator ( 3) with an idle compressor (2) and which is located in the suction part of the compressor (2); ii) a control mechanism (8) that delays the opening of the solenoid valve (16) for a period that elapses from the start-up of the compressor (2) until the torque limit is reached. 2. A cooling device (1) according to claim 1, characterized in that the cooling circuit (9) comprises: i) a bypass line (7) that is located between the solenoid valve (6) and the compressor suction part (2) and which allows the refrigerant to flow to the suction part of the compressor (2), thereby establishing a pressure balance in the suction and discharge parts of the compressor (2). 3. A cooling device (1) according to claim 1, characterized in that the cooling circuit (9) comprises: i) a bypass line (17) that balances the pressure when the solenoid valve (6) is blocked to prevent migration of the refrigerant, and which is installed between the suction and discharge parts of the compressor (2); ii) an electromagnetic control valve (116) that is installed on the bypass line (17).

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