The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 29, 1993
Filed:
Feb. 20, 1992
Antonius A Benschop, Eindhoven, NL;
Johannus C Roelofs, Valkenswaard, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A motor compressor unit comprises a hermetically sealed housing, a vibration motor with a rotationally vibrating drive shaft, and a symmetrical twin free-piston compressor comprising two oppositely disposed identical free pistons which can be reciprocated in respective cylinders by the drive shaft. In order to minimize piston drift from the center position, each cylinder is formed with a duct connecting the respective compression space to the space between the housing and the motor-compressor where the suction pressure prevails, which ducts are situated at equal distances from the respective cylinder end walls and can be closed by the respective pistons. As a result of this, the pressure in both cylinders is built up with the same swept volume and piston drift is minimized.