Miniature rotary compressor, and methods related thereto

Abstract

Disclosed is a rolling piston rotary compressor for use with primary refrigerants that is miniaturized for portable and mobile applications for which size and weight are often crucial. The miniature rotary compressor comprises a compressor mechanism, a brushless DC motor and a casing. The compressor mechanism comprises, a cylinder, a shaft having an eccentric part, one or more bearings to support the shaft, a roller, a vane, an oil sump, openings for communicating with lubricant oil and refrigerant, and inlet and discharge ports. The compressor mechanism and the motor are housed in a hermetically sealed or semi-hermetically sealed casing. The configuration and design of the present invention allow the realization of an ultralight miniature compressor. The miniature rotary compressor provides a higher power density and comparable efficiency as compared to state-of-the-art refrigerant-based rotary compressors. Also disclosed are methods of manufacturing the miniature rotary compressor.

Description

CROSS REFERENCE TO RELATED APPLICATION [0001] This is a non-provisional application claiming the benefit of and priority to provisional patent application Ser. No. 60 / 640,699 filed on Dec. 29, 2004, which is incorporated herein by reference.TECHNICAL FIELD [0002] The present invention relates generally to rotary compressors, and methods related thereto. Specifically, the present invention pertains to a rolling piston type miniature rotary compressor for use with primary refrigerants as the working fluid, as used in vapor compression systems. This miniature rotary compressor is especially useful in applications that require small and ultralight cooling systems, which can be battery-powered for portability and used in hot environments that are impractical for conventional air conditioning. BACKGROUND [0003] The emergence of new small-scale technologies has created an environment in which conventional space conditioning may be displaced. One area where such displacement may occur is in...

AI Technical Summary

Benefits of technology

[0012] It is, therefore, an aspect of the present invention to provide a compact, ultralight, miniature rolling piston rotary compressor having a diameter of up to about 2.5 in., axial length of up to about 3.5 in., weight of up to about 1.7 pounds, and displacement of up to about 3.0 cc / revolution.

[0013] It is another aspect of the present invention to provide an ultralight, miniature rolling piston rotary compressor that provides a higher power density and comparable efficiency as compared to state-of-the-art refrigerant-based rotary compressors.

[0014] It is another aspect of the present invention to provide an ultralight, miniature rolling piston rotary compressor that is reliable, that can be used with a range of refrigerants and can be produced cost-effectively

[0020] In one embodiment, a three-pin feed through for powering the motor drive is assembled and placed within the casing. In another embodiment, a thin-walled compressor casing is utilized while meeting the structural requirements of the ASME Pressure Vessel Code, and the hydrostatic test requirements of UL for hermetic compressors. In another embodiment, a support structure is utilized for the side-mounted outlet connection, which is used to keep the overall axial length to a minimum. In another embodiment, a muffler is incorporated in a way that oil loss is minimized while allowing for the smallest casing axial length and diameter to provide the desired cooling capacity and coefficient of performance. In another embodiment, the motor is fastened to the shaft without the use of heat shrinking.

[0021] The present invention also pertains to methods for manufacturing a miniature rolling piston rotary compressor. In one embodiment, a method for manufacturing a miniature rolling piston rotary compressor comprises the machining of component parts at a given set of tight tolerances, and incorporating a brushless DC motor that operates preferably at speeds of up to 7000 rpm. In another embodiment, a manufacturing method comprises assembling a cylinder, a shaft, roller, a vane, top and bottom bearing flanges with a drive motor and a casing. In another embodiment, the cylinder, roller, vane, shaft, top and bottom bearing flanges are each assembled prior to assembly with the drive motor, and casing. In another embodiment, the rotor is attached to the shaft in such a way as to avoid heating, which may damage the motor magnet. In another embodiment, a method of plasma-welding the casing is utilized in such a way as to avoid heat damage to the motor.

Problems solved by technology

However, even the smallest of these known rolling piston rotary compressors are too bulky and / or non-mobile and / or do not provide sufficient cooling effect for applications that require small and ultralight portable compressors.

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