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:
Oct. 30, 1990
Filed:
Jul. 14, 1988
Akito Uchida, Nagano, JP;
Iwao Sakaguchi, Nagano, JP;
Kabushiki Kaisha Nagano Keiki Seisakusho, Tokyo, JP;
Abstract
A vacuum pump provided with a restoration coil spring 18 having a reduced size and reduced biasing force to render an overall size of the pump compact includes a casing which defines therein a pumping chamber 6 and an operational chamber 3; a piston 7 reciprocally disposed in the pumping chamber, the piston dividing the pumping chamber into front and rear compartments R1, R2; an operational mechanism disposed in the operational chamber for moving the piston; and, a piston rod 4 having one end connected to the piston, the piston rod extending through the rear compartment and the operational chamber. The operational mechanism includes a solenoid armature 13 on the piston rod, and an electromagnet 14, 15 in the operational chamber.