WO2009149803A2

WO2009149803A2 - Air-conditioning system

Info

Publication number: WO2009149803A2
Application number: PCT/EP2009/003423
Authority: WO
Inventors: Doan Nguyen Van; Tilo SCHÄFER
Original assignee: Ixetic Mac Gmbh
Priority date: 2008-06-10
Filing date: 2009-05-14
Publication date: 2009-12-17
Also published as: EP2304343A2; EP2304343B1; DE112009001222A5; WO2009149803A3

Abstract

The invention relates to an air-conditioning system (4) comprising a coolant compressor having a low-pressure inlet (11) and a high-pressure outlet (12), and a variable flow resistance arranged in a main mass flow from the high-pressure outlet of the coolant compressor to a consumer. The invention is characterised in that a mass flow regulating device in the main mass flow has a variable flow resistance that can be adjusted by means of a control device (32).

Description

Klimasvstem

The invention relates to an air conditioning system with a refrigerant compressor, which has a low-pressure inlet and a high-pressure outlet, and with a variable flow resistance, which is arranged in a main mass flow from the high-pressure outlet of the refrigerant compressor to a consumer.

European Patent Application EP 1 091 125 A2 discloses a swash plate compressor with a control valve in the form of a solenoid valve which comprises a control piston. By varying an equilibrium of forces on the control piston by means of a magnetic force, it is possible to vary the main mass flow which flows through a constant throttle or a flow resistance.

The object of the invention is to provide an air conditioning system with a refrigerant compressor, which has a low-pressure inlet and a high-pressure outlet, and with a variable flow resistance, which is arranged in a main mass flow from the high-pressure outlet of the refrigerant compressor to a consumer, which is simple and inexpensive to produce ,

The object is achieved in a climate system with a refrigerant compressor, which has a low-pressure inlet and a high-pressure outlet, and with a variable flow resistance, which is arranged in a main mass flow from the high-pressure outlet of the refrigerant compressor to a consumer, characterized in that a mass flow control device in the main mass flow a variable Contains flow resistance, which is adjustable by means of a control device. The arranged in the main mass flow flow resistance is actively adjustable according to an essential aspect of the invention from the outside and provides, inter alia, the advantage that the main mass flow of the refrigerant compressor can be varied depending on demand in a simple manner. In addition, the main mass flow can be kept constant regardless of the drive speed of the refrigerant compressor. Furthermore, the mass flow control device according to the invention fulfills high requirements with regard to the control quality and the dynamics. Finally, the mass flow control device according to the invention is compact and inexpensive to produce.

A preferred embodiment of the air conditioning system is characterized in that the variable flow resistance is designed as a variable throttle. The main mass flow is varied by adjusting the flow cross sections at the variable throttle.

A further preferred exemplary embodiment of the air conditioning system is characterized in that the mass flow control device comprises a piston slide valve with a valve piston which is acted on by control pressure surfaces in front of and behind the variable flow resistance. The control pressure surfaces are preferably provided at the two ends of the valve piston. Preferably, a valve spring is biased against one end of the valve piston.

A further preferred embodiment of the air conditioning system is characterized in that the spool valve has a pressure port, which is acted upon by the pressure before the variable flow resistance. The pressure connection is connected directly or indirectly, for example with the interposition of an oil separator, to the high-pressure outlet of the refrigerant compressor.

A further preferred exemplary embodiment of the air conditioning system is characterized in that the piston slide valve has a drive chamber pressure connection, which is acted on by a drive chamber pressure of the refrigerant compressor. The drive-chamber pressure connection is preferably in direct communication with a drive chamber of the refrigerant compressor.

A further preferred exemplary embodiment of the air conditioning system is characterized in that the valve piston of the piston slide valve has a control edge which opens or closes a connection between the pressure connection and the drive chamber pressure connection in dependence on a pressure difference at the control pressure surfaces of the valve piston. Such a piston valve with only one control edge is also referred to as a single edge regulator.

A further preferred embodiment of the air conditioning system is characterized in that the valve piston of the spool valve has a further control edge, the one Connection between the engine pressure port and a low pressure port of the spool valve in response to the pressure difference at the control pressure surfaces of the valve piston opens or closes. Such a piston valve with exactly two control edges is also referred to as two-edge rule. The low pressure port of the spool valve is in communication with the low pressure input of the refrigerant compressor.

A further preferred embodiment of the air conditioning system is characterized in that an oil separator between the high pressure outlet of the refrigerant compressor and the pressure port of the spool valve is arranged. Oil is separated from the main mass flow via the oil separator. The separated oil is returned via the spool valve back into the drive chamber of the refrigerant compressor.

A further preferred exemplary embodiment of the air conditioning system is characterized in that the refrigerant compressor comprises a drive chamber, which is connected to the low-pressure inlet of the refrigerant compressor with the interposition of an outlet throttle. The pressure prevailing in the engine room is called the engine room pressure. The drive chamber communicates with the drive chamber pressure port of the spool valve.

A further preferred embodiment of the air conditioning system is characterized in that a bypass flow flows from the oil separator into the drive chamber even when the valve piston is closed. As a result, the lubrication of the drive room is maintained.

Another preferred embodiment of the air conditioning system is characterized in that the bypass flow is represented by a leakage flow through the spool valve. The leakage flow is ensured, for example, by appropriate tolerances of the individual parts, such as the valve piston, of the piston slide valve.

Another preferred embodiment of the air conditioning system is characterized in that the bypass flow flows through a bypass channel. The bypass channel is preferably arranged separately from the spool valve.

A further preferred embodiment of the air conditioning system is characterized in that a filter device between the oil separator and the spool valve ange- is orders. As a result, an impairment of the operation of the mass flow control device is avoided by impurities contained in the lubricating oil.

Further advantages, features and details of the invention will become apparent from the following description in which, with reference to the drawings, various embodiments are described in detail. Show it:

1 shows an air conditioning system according to a first embodiment with a

Edges and

FIG. 2 shows a similar air conditioning system as in FIG. 1 with a two-edge regulator.

FIGS. 1 and 2 each show an air conditioning system 1 with a refrigerant compressor 4 in the form of a hydraulic circuit diagram. The refrigerant compressor 4 is preferably designed as a swivel ring compressor or swash plate compressor and is supplied via a low-pressure inlet 11 with refrigerant, which is acted upon by low pressure. In the refrigerant compressor 4, the refrigerant is then subjected to high pressure and conveyed via a high-pressure outlet 12 to a consumer. The consumer is, for example, a gas cooler or condenser, which may be equipped with a blower. The air conditioning system 1 may further include an accumulator having a coolant dryer, an evaporator, an expansion valve, an internal heat exchanger, a blower, and a temperature controller.

In a connecting line 14 between the low-pressure inlet 11 and the refrigerant compressor 4, a branch 15 is provided, whose function will be explained later. The outlet of the refrigerant compressor is connected via a high-pressure line 18 with an oil separator 20 in connection. The oil separator 20 is connected via a further high pressure line 22 to the high pressure outlet 12 in connection. In the high-pressure line 22, two further branches 24, 25 are provided, whose function will also be explained later.

The climate system 1 according to the invention comprises for mass flow control of the main mass flow an adjustable measuring device in the form of a variable flow resistance 28, which is designed as a variable throttle. By a bent arrow 29 is symbolically indicated that the adjusting throttle 28 via an amplifier 30 by means of a control device 32nd is controlled. The controller 32, as indicated by arrows, setpoint values, such as a desired temperature supplied.

From the branch 24, a connecting line 34, in which the oil separator 20 is arranged, extends to a pressure port 35 of a piston valve 40. The spool valve 40 further comprises a drive pressure chamber 36, which via a further connecting line 37 with a drive chamber 38 of the refrigerant compressor 4 in Connection stands. The drive chamber 38 is connected via a further connecting line 39, in which an outlet throttle 42 is arranged, with the branch 15 of the connecting line 14 in connection.

The piston valve 40 includes a longitudinally displaceable valve piston 44 which is acted upon at one end by the biasing force of a valve spring 45. At the end with the valve spring 45, a control line 46 is connected to the spool valve 40. The control line 46 starts from the branch 25, so that the valve spring 45 facing the end of the valve piston 44 is acted upon by the pressure after the adjusting throttle 28.

The pressure in front of the adjusting throttle 28 is supplied via a further control line 48 to the end of the valve piston 44 facing away from the valve spring 45. The pressure in the drive chamber 38, which also prevails in the connecting line 37 as well as on the drive chamber pressure connection 36, is referred to as drive-chamber pressure.

The piston slide valve 40 shown in FIG. 1 comprises a valve piston 44 with exactly one control edge 51. Such a piston slide valve is also referred to as a single-edge regulator. In the illustrated position of the valve piston 44, a connection between the pressure port 35 and the drive pressure chamber 36 of the spool valve 40 is interrupted by a collar of the valve piston 44 with the control edge 51. When the valve piston 44 shifts to the right, that is to the valve spring 45, due to the pressure difference applied to the control pressure surfaces 45, the control edge 51, as soon as the pressure difference exceeds a certain value, the connection between the pressure port 35th and the engine pressure port 36, so that coolant and lubricating oil separated in the oil separator 20 are returned via the spool valve 40 and the connecting pipe 37 back into the driving space 38 of the refrigerant compressor 4 is promoted. As soon as the pressure difference at the control pressure surfaces at the ends of the valve piston 44 decreases, the valve piston 44 is moved back into its initial position shown by the biasing force of the valve spring 45.

In the embodiment shown in Figure 2, the valve piston 44 of the spool valve 40 in addition to the control edge 51, a further control edge 52 which is provided on the same collar as the control edge 51. Because of the two control edges 51 and 52, the spool valve 40 shown in Figure 2 is also referred to as two-edge rule. The first control edge 51 performs the same function as in the embodiment shown in Figure 1. The second control edge 52 cooperates with a low-pressure connection 56, which communicates via a connecting line 55 with a further branch 54, which is provided between the inlet of the refrigerant compressor 4 and the low-pressure inlet 11. In the position of the valve piston 44 shown in FIG. 2, the drive-chamber pressure connection 36 communicates with the low-pressure connection 56. When the valve piston 44 far enough due to the applied to the control pressure surfaces at the ends of the valve piston 44 pressure difference against the biasing force of the valve spring 45 to the right, ie to the valve spring 45, moves, then this connection is interrupted by the further control edge 52.

According to one essential aspect of the invention, the adjusting throttle 28 is thus combined in the main mass flow with a pressure compensator for the drive chamber pressure in the drive chamber 38 of the refrigerant compressor 4. The spool valve 40 operates as a pressure compensator as a function of a substantially constant pressure drop across the variable throttle 28. The mass flow is varied by adjusting the flow cross sections of the variable throttle 28. By this arrangement, a simple and robust control device is provided to adjust the main mass flow of the refrigerant to the specifications and needs of the consumer.

The oil separator shown in Figure 2 can also be when using a two-edge controller with a separate throttled line connected to the drive chamber (not shown), so that the oil supply of the drive chamber is secured regardless of the position of the two-edge controller. LIST OF REFERENCES

Claims

claims

An air conditioning system having a refrigerant compressor (4) having a low pressure inlet (11) and a high pressure outlet (12) and having a variable flow resistance arranged in a main mass flow from the high pressure outlet (12) of the refrigerant compressor (4) to a consumer. characterized in that a Massenstromre- geleinrichtung in the main mass flow includes a variable flow resistance (28) which is adjustable by means of a control device (32).

2. Air conditioning system according to claim 1, characterized in that the variable flow resistance (28) is designed as an adjusting throttle.

3. Air conditioning system according to one of the preceding claims, characterized in that the mass flow control device comprises a piston slide valve (20) with a valve piston (44) which is acted upon at control pressure surfaces with the pressure in front of and behind the variable flow resistance (28).

4. Air conditioning system according to claim 3, characterized in that the piston slide valve (40) has a pressure connection (35), which is acted upon by the pressure in front of the variable flow resistance (28).

5. Air conditioning system according to claim 3 or 4, characterized in that the piston slide valve (40) has a drive pressure chamber (36) which is acted upon by a drive-chamber pressure of the refrigerant compressor (4).

6. The air conditioning system according to claim 5, characterized in that the valve piston (44) of the spool valve (40) has a control edge (51), the connection between the pressure port (35) and the drive pressure chamber (36) in response to a pressure difference across the Control pressure surfaces of the valve piston (44) opens or closes.

7. Air conditioning system according to claim 6, characterized in that the valve piston (44) of the spool valve (40) has a further control edge (52) which has a connection between the drive pressure chamber (36) and a low-pressure connection (56) of the KoI benschieberventils (40) in response to the pressure difference at the control pressure surfaces of the valve piston (44) opens or closes.

8. Air conditioning system according to claim 6 or 7, characterized in that an oil separator (20) between the high pressure outlet (12) of the refrigerant compressor (4) and the pressure port (35) of the spool valve (40) is arranged.

9. Air conditioning system according to one of the preceding claims, characterized in that the refrigerant compressor (4) comprises a drive chamber (38), with the interposition of an outlet throttle (42) with the low pressure inlet (11) of the refrigerant compressor (4) is in communication.

10. Air conditioning system according to one of the preceding claims, characterized in that even with the valve piston (44) closed, a bypass flow from the oil separator (20) flows into the drive chamber.

1 1. An air conditioning system according to claim 10, characterized in that the bypass flow of a leakage flow through the spool valve (40) is shown.

12. Air conditioning system according to claim 10, characterized in that the bypass flow flows through a bypass channel.

13. Air conditioning system according to one of the preceding claims, characterized in that a filter device between the oil separator (20) and the piston slide valve (40) is arranged.