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:
Jul. 14, 2015
Filed:
Dec. 13, 2012
Schlumberger Technology Corporation, Sugar Land, TX (US);
Shigeru Sato, Inagi, JP;
Hideyuki Kamei, Yokohama, JP;
Schlumberger Technology Corporation, Sugar Land, TX (US);
Abstract
Apparatus to provide a time reference are disclosed herein. An example apparatus disclosed herein includes a resonator. A first cap is coupled to a first side of the resonator to define a first cavity, and a second cap is coupled to a second side of the resonator to define a second cavity. The first cavity and the second cavity provide a first vacuum in which the resonator is to resonate. The resonator, the first cap and the second cap have substantially identical thermal expansion coefficients. The example apparatus also includes a vacuum chamber surrounding the resonator, the first cap and the second cap. The vacuum chamber is to provide a second vacuum in which the resonator, the first cap and the second cap are disposed. A frequency of resonance of the resonator in the first vacuum is to provide a time reference.