Single stage piston compressor or multistage piston compressor for cooling of an electrical motor for a single stage piston compressor or for a multistage piston compressor

Abstract

A multistage piston compressor and a method for cooling of an electrical motor for a multistage piston compressor. Conventional piston compressors produce a high part of heat dissipation. This influences negatively the energy balance of the piston compressor and requires a high expenditure in cooling agents for conserving and treating with care the piston compressor. It is therefore disclosed to furnish the always present volume changeable free chamber (19) at the piston compressor (1) as a pressure chamber and a suction chamber, and to connect this volume changeable free chamber (19) to the atmosphere through the inner chamber of the electrical motor (2).

Description

[0001] 1. Field of the Invention[0002] The Invention relates to a single stage piston compressor or to a multistage piston compressor according to the preamble of claim 5.[0003] 2. Brief Description of the Background of the Invention Including Prior Art[0004] Such piston compressors are employed in particular in the vehicle industry. Such a piston compressor in a two-stage embodiment is described in detail for example in the German printed Patent document DE 197 15 291 A1. The German printed Patent document DE 197 15 291 A1 is herewith incorporated by reference as if fully set forth herein. This two-stage piston compressor comprises a compressor casing forming a cylindrical low-pressure chamber with a larger low-pressure piston and a cylindrical high-pressure chamber with a smaller high-pressure piston. Here, the low-pressure chamber and the high-pressure chamber are disposed on a common axis and the low-pressure piston and the high-pressure piston are formed a single piece with a c...

AI Technical Summary

Benefits of technology

"The present invention is a piston compressor that includes a piston compressor proper, an electrical motor, and a mechanical drive. The mechanical drive converts the rotating motion of the electric motor into an oscillating linear motion and transfers it onto the piston compressor proper. The compressor has a volume changeable pressure chamber with a pressure piston and a volume changeable low-pressure chamber with a low-pressure piston and a volume changeable high-pressure chamber with a high-pressure piston. A volume changeable free chamber is disposed between the low-pressure piston and the high-pressure piston. The volume changeable free chamber is connected to the outer atmosphere through an admission check valve. The invention has the advantage of eliminating the need for expensive cooling steps for the piston compressor and the electrical motor, saving production costs. It also simplifies the construction of the piston compressor and saves additional drive energy. The piston compressors according to the present invention can be employed for all kinds of protection."

Problems solved by technology

Piston compressors of this kind are associated with the disadvantage that an essential part of the drive energy is converted into heat and thus negatively influences the efficiency of the technical unit.

In this way the electric motor produces its own heat, wherein this heat then has to be led away or cooled again in an expensive way and for the protection of the insulations.

This limits on the one hand the lifetime of the electrical motors and requires additional and expensive cooling steps at the electrical motor.

The internal friction of this enclosed air volume in the free chamber depends on the construction of the piston compressor, but at any rate represents a power dissipation for which an additional drive power has to be furnished in a non-justifiable manner.

The this way generated warming up at the piston compressor is either compensated to an acceptable measure by a corresponding material selection or material dimensioning or the released heat energy is again cooled expensively.

This all interferes with the efficiency of the technical unit and renders the technical unit expensive and cost intensive because of the increased cooling provisions.

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