COMPRESSOR HOUSING HAVING PRESSURE LIMITATION, AND METHOD FOR OPERATION

Abstract

A housing of an air-conditioning compressor comprising at least two housing components is proposed, wherein the at least two housing components are sealed with respect to each other and are connected to each other by means of screws, and the housing components comprise aluminum or an aluminum alloy and the screws are ultra-high-strength screws. UHS screws are means for further ensuring an excess pressure safety function.

Claims

1. A housing of a refrigerant compressor comprising at least two housing components, wherein the at least two housing components are sealed with respect to each other and are connected to each other by means of screws, characterized in that the housing components comprise aluminum or an aluminum alloy and are connected to each other by means of ultra-high-strength screws.

2. The housing as claimed in claim 1, wherein there is a surface pressure between the housing components.

3. The housing as claimed in claim 1, wherein a resilient seal is constructed between the housing components.

4. The housing as claimed in claim 1, wherein a flat seal is constructed between the housing components.

5. The housing as claimed in claim 4, wherein the walls of the housing components in the region of the screw connection in the region of the flat seal are less than 10 mm thick.

6. The housing as claimed in claim 1, wherein the screws ultra-high-strength screws of the strength class 14.8//15.8//16.8 according to VDA 235-205.

7. The housing as claimed in claim 1, wherein a refrigerant used in the refrigerant compressor is R744.

8. The housing as claimed in claim 3, wherein the housing and the seal are configured for a pressure range of up to 100 bar.

9. The housing as claimed in claim 1, wherein the screws have a diameter of 7 or 8 mm.

10. A method for operating a refrigerant compressor as claimed in claim 1, wherein, with the housing components of aluminum or an aluminum alloy in combination with the ultra-high-strength screws, a reversible pressure limitation function is provided by relieving the separation joint between the housing components in order to reduce pressures between a maximum operating pressure and a bursting pressure.

Description

DRAWINGS

[0017] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0018] FIG. 1 is a schematic illustration of the exemplary embodiment,

[0019] FIG. 2 shows further details.

DETAILED DESCRIPTION

[0020] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0021] The air-conditioning compressor 1 according to the invention comprises housing components 2 which are connected to each other by means of ultra-high-strength screws 3. In this instance, a variant the connection of two housing components or a plurality of housing components is configured as in FIG. 2 with a screw 3 which extends almost over the structural height of the compressor. The housing component and the connections and seals thereof when R744 is used must withstand up to 100 bar internal pressure.

[0022] The housing components 2 are positioned one on the other with flat seals 4 in a state sealed relative to each other. In order to achieve uniform pressing of the flat seal, the number of screws corresponds to at least that of the pistons since they are arranged between the pistons when a piston compressor is used. With piston numbers less than 6, a plurality of screws between the pistons are also conceivable.

[0023] The use of ultra-high-strength screws and the configuration of the screw connection is carried out in such a manner that, when a defined pressure is exceeded, the surface pressure of the flat seals between the housing components is not sufficient to seal so that leakage occurs and consequently no further significant pressure increase occurs. Consequently, there is produced a safety function which acts as an additional function to other excess pressure components or as an individual safety function. In contrast to the use of standard screws, UHS screws as a result of their greater elongation at rupture and their higher apparent yielding point enable a reversible behavior of the described pressure limitation device.

[0024] The screws are intended to be configured in such a manner that they withstand the bursting pressure so that component and assembly tolerances can be absorbed in order to be able to ensure the described safety function. The bursting pressure should be above the response pressure of the safety function by a factor of from 1.1 to 1.8.

[0025] Bainitically quenched and tempered screws (UHS screws) have high elongations at rupture with high strengths. It is thereby possible to configure in particular screw connections with large clamping lengths and different material pairings and thermal expansion. Housing components of aluminum are thus connected using the ultra-high-strength steel screw.

[0026] When ultra-high-strength screws are used, the screw diameter may be selected to be smaller than with standard screws. The ultra-high-strength screw is thereby softer than a standard screw of lower strength and accordingly larger diameter. As a result of the smaller thread diameter, the ultra-high strength screw must absorb lower mechanical and thermal auxiliary screwing forces, which at the same time leads to a low loading of the housing in the screw head support region and in the nut thread.

[0027] The advantages when ultra-high-strength screws are used to connect housing components of a refrigerant compressor are in this instance the smaller structural space as a result of the smaller diameter of the ultra-high-strength screws, the higher level of resilience thereof and the lower weight of the entire subassembly.

[0028] During operation of the refrigerant compressor, it is important that, with housing components of aluminum or an aluminum alloy in combination with ultra-high-strength screws, a reversible pressure limitation function can be represented by relieving the separation joint between the housing components in order to reduce pressures between the maximum operating pressure and the bursting pressure.

LIST OF REFERENCE NUMERALS

[0029] 1 Compressor

[0030] 2 Housing components

[0031] 3 Screw

[0032] 4 Flat seal