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:
Sep. 26, 1995
Filed:
Oct. 04, 1993
Daniel G Bills, Boulder, CO (US);
Michael D Borenstein, Louisville, CO (US);
Granville-Phillips Company, Boulder, CO (US);
Abstract
A device for determining a pressure of gas in an evacuated chamber including a cylinder positioned in fluid communication with the evacuated chamber with the cylinder forming a compressed gas chamber, a reciprocating piston received within the cylinder and mounted for reciprocal movement therein, a port or valve for providing selective fluid communication between the compressed gas chamber and the evacuated chamber is disclosed. A drive mechanism is provided for reciprocating the piston between a retracted position, where the compressed gas chamber communicates with the evacuated chamber, and an extended position where communication between the compressed gas chamber and the evacuated chamber is interrupted, the position being a position where a pressure transducer determines that a predetermined pressure differential between the chambers has been reached. In the preferred embodiment, a stepper motor is used to measure a distance travelled by the piston at the point where the predetermined pressure differential is reached. Utilizing these parameters, a processor then determines the pressure of the gas within the evacuated chamber.