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:
Mar. 31, 1992
Filed:
Dec. 21, 1990
Charles E Hixon, Huffman, TX (US);
Cummins Engine Company, Inc., Columbus, IN (US);
Abstract
The present invention provides a lubricant circulation system for a rock drill bit which circulates a flow of lubricant over the bit bearing surfaces to keep the bearings optimally lubricated and free to particulate contaminants from the drilling process. A lubricant pumping assembly, including a pair of nested gerotor pump elements is attached to either the drill bit cutting element or support structures so that one of the gerotors is driven by rotation of the bit cutting element or related structures and the other gerotor rotates freely. The gerotors have a corresponding tooth and recess configuration that pulls lubricant from the lubricant supply under positive pressure into a variable sized cavity formed as the gerotors rotate relative to each other and then forces lubricant to the bearing surfaces. Lubricant may optionally be pumped back to the lubricant supply with continued rotation of the gerotors or out of the journal area with the drilling cuttings for return to the surface.