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. 16, 1987
Filed:
May. 19, 1986
William H Kent, Westford, MA (US);
Robert C Steel, Westford, MA (US);
Gas Research Institute, Chicago, IL (US);
Abstract
A toroidal liquid filled sensor measures rotation with respect to vertical in any plane normal to the earth's surface and comprises a sealed, non-conductive, hollow toroidal housing of square or rectangular cross section with an interior circular cavity or channel of like cross section. A discontinuous resistive strip circles the interior surface of the channel outer wall and a continuous conductive strip or collector circles the exterior surface of the channel inner wall. Electrical contacts are connected to each end of the resistive strip and a third contact is connected to the collector. The channel contains a quantity of dielectric or resistive fluid which has total volume less than a 30.degree. sector of the channel. Electrical damping (R-C time constant) is achieved by balancing the capacitance and resistance parameters. A single sensor has a linear range greater than 270.degree.. The combination of two sensors allows measurement of full 360.degree. of rotation and use of a sensor array allows measurement in 2 degrees of freedom for measuring pitch and roll. The sensor system is suitable for use in many applications and in particular may be used as part of a system for horizontal, guided boring in the earth.