Air conditioning unit with refrigerant charging and recovery function

Abstract

The present invention provides an air conditioning unit with a refrigerant filling and recovery function. The air conditioning unit includes a condenser, a compressor and a refrigerant pump in a refrigerant cycle, and also includes a refrigerant tank. A refrigerant replenishment pipeline is provided between the refrigerant tank and the condenser. The refrigerant pump has a first state in which it is connected to the lubrication pipeline and the pumping direction is from the condenser to the compressor, and a second state in which it is connected to the refrigerant replenishment pipeline and the pumping direction is from the refrigerant tank to the condenser. The air conditioning unit with a refrigerant filling and recovery function provided by the present invention is provided with a refrigerant tank on the air conditioning unit, and the existing refrigerant pump on the air conditioning unit is used and controlled by the on-off mechanism to directly realize the process of filling the refrigerant during the installation and commissioning of the unit and recovering the refrigerant during maintenance, thereby overcoming the need for an independent external refrigerant filling and recovery machine in the prior art, thereby improving the convenience of installation and maintenance of the air conditioning unit.

Description

Technical Field

[0001] The invention relates to the technical field of refrigerant heat exchange devices, in particular to an air conditioning unit with a refrigerant charging and recovery function. Background Art

[0002] In centrifugal chillers that use refrigerant to lubricate bearings, a refrigerant pump must be installed. Before the main motor of the unit is running, the refrigerant pump should be turned on first to supply the bearings with refrigerant of sufficient flow and pressure difference to ensure adequate bearing lubrication and prevent bearing wear. After the pressure difference between the evaporator and condenser of the unit is established, the pressure difference between the condenser and the evaporator can be used to press the liquid refrigerant in the condenser to the compressor bearings to ensure the bearings are supplied with liquid. At this time, the refrigerant pump can be turned off. When the unit is shut down, since the pressure difference between the condenser and the evaporator gradually decreases, the refrigerant pump can be turned on to ensure the bearings are supplied with liquid when the main motor is idling. After the main motor stops completely, the refrigerant pump can be turned off again. However, when debugging and repairing centrifugal chillers, it is often necessary to fill and recover the refrigerant in the unit. At this time, an external refrigerant filling and recovery machine is required. The equipment is large in size, difficult to carry, and inconvenient for engineering maintenance. Summary of the invention

[0003] In order to solve the technical problem of the difficulty in the debugging and maintenance process of the air-conditioning unit in the prior art, an air-conditioning unit with refrigerant filling and recovery function is provided, which utilizes the refrigerant pump of the air-conditioning unit to fill and recover the refrigerant, thereby overcoming the need of external refrigerant filling and recovery machines in the prior art.

[0004] An air-conditioning unit, comprising a refrigerant pump and a condenser and a compressor in a refrigerant cycle, a lubrication pipeline being arranged between the condenser and the compressor, the air-conditioning unit further comprising a refrigerant tank, a replenishment pipeline being arranged between the refrigerant tank and the condenser, the refrigerant pump having a first state in which the refrigerant pump is connected to the lubrication pipeline and the pumping direction is from the condenser to the compressor, and the refrigerant pump having a second state in which the refrigerant pump is connected to the replenishment pipeline and the pumping direction is from the refrigerant tank to the condenser.

[0005] A first on-off mechanism is provided between the refrigerant tank and the inlet of the refrigerant pump, a second on-off mechanism is provided between the condenser and the inlet of the refrigerant pump, a third on-off mechanism is provided between the outlet of the refrigerant pump and the compressor, and a fourth on-off mechanism is provided between the outlet of the refrigerant pump and the condenser, and in the first state, the second on-off mechanism and the third on-off mechanism are connected and the first on-off mechanism and the fourth on-off mechanism are disconnected, and in the second state, the first on-off mechanism and the fourth on-off mechanism are connected and the second on-off mechanism and the third on-off mechanism are disconnected.

[0006] A recovery pipeline is further provided between the refrigerant pump outlet and the refrigerant tank, and the refrigerant pump has a third state in which the condenser and the refrigerant tank are connected through the recovery pipeline and the pumping direction is from the condenser to the refrigerant tank.

[0007] The recovery pipeline is provided with a fifth on-off mechanism, and in the third state, the second on-off mechanism and the fifth on-off mechanism are connected, and the first on-off mechanism, the third on-off mechanism and the fourth on-off mechanism are disconnected.

[0008] The first on-off mechanism, the second on-off mechanism, the third on-off mechanism, the fourth on-off mechanism and the fifth on-off mechanism are one of a ball valve, a stop valve, a solenoid valve or a butterfly valve.

[0009] The air conditioning unit further comprises an evaporator and a throttling mechanism, and the compressor, the condenser, the throttling mechanism and the evaporator are sequentially connected in series to form a refrigerant heat exchange cycle.

[0010] An air return pipe is arranged between the compressor and the evaporator.

[0011] The compressor includes a bearing, and an end of the lubrication pipeline and an end of the return air pipe are both in communication with the bearing.

[0012] The volume of the refrigerant tank is greater than the amount of refrigerant in the refrigerant heat exchange cycle.

[0013] A filter is also provided between the condenser and the compressor.

[0014] The air conditioning unit is a centrifugal chiller.

[0015] The air-conditioning unit with refrigerant filling and recovery function provided by the present invention is provided with a refrigerant tank on the air-conditioning unit, and the existing refrigerant pump on the air-conditioning unit is utilized and controlled by the on-off mechanism to directly realize the process of filling refrigerant during installation and commissioning of the unit and recovering refrigerant during maintenance, thereby overcoming the need for an independent external refrigerant filling and recovery machine in the prior art, thereby improving the convenience of installation and maintenance of the air-conditioning unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A structural schematic diagram of an air-conditioning unit of an embodiment of an air-conditioning unit with a refrigerant charging and recovery function provided by the present invention;

[0017] Figure 2 Another structural schematic diagram of an embodiment of an air-conditioning unit with a refrigerant charging and recovery function provided by the present invention;

[0018] In the figure:

[0019] 1. Condenser; 2. Compressor; 3. Refrigerant pump; 4. Refrigerant tank; 5. First on-off mechanism; 6. Second on-off mechanism; 7. Third on-off mechanism; 8. Fourth on-off mechanism; 9. Fifth on-off mechanism; 10. Evaporator. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] like Figure 1 and Figure 2 The air-conditioning unit shown in the figure includes a refrigerant pump 3 and a condenser 1 and a compressor 2 in a refrigerant cycle, a lubrication pipeline is arranged between the condenser 1 and the compressor 2, and the air-conditioning unit also includes a refrigerant tank 4, a replenishing pipeline is arranged between the refrigerant tank 4 and the condenser 1, the refrigerant pump 3 has a first state in which it is connected to the lubrication pipeline and the pumping direction is from the condenser 1 to the compressor 2, and the refrigerant pump 3 has a second state in which it is connected to the replenishing pipeline and the pumping direction is from the refrigerant tank 4 to the condenser 1. In the first state, the refrigerant pump 3 pumps the liquid refrigerant in the condenser 1 into the compressor 2 to meet the purpose of refrigerant lubrication of the compressor 2, and in the second state, the refrigerant pump 3 sends the refrigerant in the refrigerant tank 4 to the condenser 1 to realize the refrigerant injection, which overcomes the problem of difficulty in transportation caused by the need for an external refrigerant injection machine for injection, which is not conducive to engineering maintenance.

[0022] A first on-off mechanism 5 is arranged between the refrigerant tank 4 and the inlet of the refrigerant pump 3, a second on-off mechanism 6 is arranged between the condenser 1 and the inlet of the refrigerant pump 3, a third on-off mechanism 7 is arranged between the outlet of the refrigerant pump 3 and the compressor 2, and a fourth on-off mechanism 8 is arranged between the outlet of the refrigerant pump 3 and the condenser 1, and in the first state, the second on-off mechanism 6 and the third on-off mechanism 7 are connected and the first on-off mechanism 5 and the fourth on-off mechanism 8 are disconnected, so that the condenser 1 and the compressor 2 are connected to meet the purpose of refrigerant lubrication, and in the second state, the first on-off mechanism 5 and the fourth on-off mechanism 8 are connected and the second on-off mechanism 6 and the third on-off mechanism 7 are disconnected, so that the condenser 1 and the refrigerant tank 4 are connected to meet the refrigerant perfusion, wherein the first on-off mechanism 5, the second on-off mechanism 6, the third on-off mechanism 7 and the fourth on-off mechanism 8 can all be effectively opened and blocked.

[0023] A recovery pipeline is also provided between the outlet of the refrigerant pump 3 and the refrigerant tank 4, and the refrigerant pump 3 has a third state in which the condenser 1 and the refrigerant tank 4 are connected through the recovery pipeline and the pumping direction is from the condenser 1 to the refrigerant tank 4, thereby recovering the refrigerant in the air-conditioning unit into the refrigerant tank 4 to complete the refrigerant recovery.

[0024] The recovery pipeline is provided with a fifth on-off mechanism 9, and in the third state, the second on-off mechanism 6 and the fifth on-off mechanism 9 are connected, and the first on-off mechanism 5, the third on-off mechanism 7 and the fourth on-off mechanism 8 are disconnected.

[0025] The first on-off mechanism 5 , the second on-off mechanism 6 , the third on-off mechanism 7 , the fourth on-off mechanism 8 and the fifth on-off mechanism 9 are one of a ball valve, a stop valve, a solenoid valve or a butterfly valve.

[0026] The air-conditioning unit also includes an evaporator 10 and a throttling mechanism. The compressor 2, the condenser 1, the throttling mechanism and the evaporator 10 are connected in series in sequence to form a refrigerant heat exchange cycle. When the air-conditioning unit is working, the refrigerant performs normal heat exchange in the refrigerant heat exchange cycle.

[0027] An air return pipe is provided between the compressor 2 and the evaporator 10, so that the refrigerant can flow back into the evaporator 10 through the air return pipe and finally enter the refrigerant heat exchange cycle.

[0028] The compressor 2 includes a bearing, and the end of the lubrication pipeline and the end of the return pipe are both connected to the bearing. Before the compressor 2 is operated, the refrigerant pump 3 is first turned on to put the refrigerant pump 3 in the first state, and the liquid refrigerant pump 3 at the bottom of the condenser 1 is pumped to the bearing of the compressor 2 to supply the bearing with a refrigerant with sufficient flow and pressure difference, to ensure sufficient lubrication of the bearing and prevent bearing wear, and finally returns to the evaporator 10 through the return pipe. After the pressure difference between the evaporator 10 and the condenser 1 of the unit is established, the pressure difference between the condenser 1 and the evaporator 10 can be used to press the liquid refrigerant in the condenser 1 to the bearing of the compressor 2 to ensure the bearing is supplied with liquid, and the refrigerant pump 3 can be turned off at this time. When the unit is shut down, since the pressure difference between the condenser 1 and the evaporator 10 gradually decreases, the refrigerant pump 3 can be turned on and switched to the first state to ensure that the bearing is supplied with liquid when the main motor of the compressor 2 is idling. After the main motor is completely stopped, the refrigerant pump 3 is turned off again to ensure reliable lubrication at the bearing.

[0029] The volume of the refrigerant tank 4 is greater than the amount of refrigerant in the refrigerant heat exchange cycle, thereby ensuring that the refrigerant in the refrigerant tank 4 meets the needs of the air-conditioning unit. At the same time, the refrigerant tank 4 can fully carry the refrigerant in the refrigerant heat exchange cycle, thereby meeting the filling and recovery of the refrigerant.

[0030] A filter is further provided between the condenser 1 and the compressor 2 .

[0031] The air conditioning unit is a centrifugal chiller.

[0032] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An air conditioning unit, comprising a refrigerant pump (3) and a condenser (1) and a compressor (2) in a refrigerant cycle, wherein a lubrication pipeline is provided between the condenser (1) and the compressor (2), characterized in that: The air conditioning unit further comprises a refrigerant tank (4), a liquid replenishing pipeline is arranged between the refrigerant tank (4) and the condenser (1), the refrigerant pump (3) has a first state in which it is connected to the lubrication pipeline and the pumping direction is from the condenser (1) to the compressor (2), and the refrigerant pump (3) has a second state in which it is connected to the liquid replenishing pipeline and the pumping direction is from the refrigerant tank (4) to the condenser (1); A first on-off mechanism (5) is provided between the refrigerant tank (4) and the inlet of the refrigerant pump (3), a second on-off mechanism (6) is provided between the condenser (1) and the inlet of the refrigerant pump (3), a third on-off mechanism (7) is provided between the outlet of the refrigerant pump (3) and the compressor (2), and a fourth on-off mechanism (8) is provided between the outlet of the refrigerant pump (3) and the condenser (1), and in the first state, the second on-off mechanism (6) and the third on-off mechanism (7) are connected and the first on-off mechanism (5) and the fourth on-off mechanism (8) are disconnected, and in the second state, the first on-off mechanism (5) and the fourth on-off mechanism (8) are connected and the second on-off mechanism (6) and the third on-off mechanism (7) are disconnected; A recovery pipeline is also provided between the outlet of the refrigerant pump (3) and the refrigerant tank (4), and the refrigerant pump (3) has a third state in which the condenser (1) and the refrigerant tank (4) are connected via the recovery pipeline and the pumping direction is from the condenser (1) to the refrigerant tank (4); The recovery pipeline is provided with a fifth on-off mechanism (9), and in the third state, the second on-off mechanism (6) and the fifth on-off mechanism (9) are connected, and the first on-off mechanism (5), the third on-off mechanism (7) and the fourth on-off mechanism (8) are disconnected; The air conditioning unit further comprises an evaporator (10) and a throttling mechanism, and the compressor (2), the condenser (1), the throttling mechanism and the evaporator (10) are sequentially connected in series to form a refrigerant heat exchange cycle.

2. The air conditioning unit according to claim 1, characterized in that: The first on-off mechanism (5), the second on-off mechanism (6), the third on-off mechanism (7), the fourth on-off mechanism (8) and the fifth on-off mechanism (9) are one of a ball valve, a stop valve, a solenoid valve or a butterfly valve.

3. The air conditioning unit according to claim 1, characterized in that: An air return pipe is provided between the compressor (2) and the evaporator (10).

4. The air conditioning unit according to claim 3, characterized in that: The compressor (2) comprises a bearing, and the end of the lubrication pipeline and the end of the return air pipe are both connected to the bearing.

5. The air conditioning unit according to claim 1, characterized in that: The volume of the refrigerant tank (4) is greater than the amount of refrigerant in the refrigerant heat exchange cycle.

6. The air conditioning unit according to claim 1, characterized in that: A filter is also provided between the condenser (1) and the compressor (2).

7. The air conditioning unit according to claim 1, characterized in that: The air conditioning unit is a centrifugal chiller.

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