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. 08, 1992
Filed:
Sep. 11, 1989
William F Marantette, Torrance, CA (US);
Optima Industries, Inc., Torrance, CA (US);
Abstract
A high speed spindle is provided which includes a rotor driven by an electric motor and provided with tapered journals received in tapered rubber bearings. Lubricating water flows to the bearings through metered openings in the journals, flowing from the openings through reverse spiral grooves in the journals which have diminishing cross section. The water flowing through the rotor also cools the rotor, as well as the collet driven by the rotor and a tool held by the collet. Rubber seals around the rotor shaft wear to a zero clearance during run-in for confining the water that exhausts from the bearings. Compressed air is introduced into the spindle to cooperate with the seals in preventing water leakage. The compressed air also reacts against a bladder that is arranged to impose an end load on one of the bearings, which is movable, to urge the bearing toward its journal. The force is varied to increase the bearing end load as rotor speed increases. The collet employs self-holding tapers to retain it in a closed position and has cam surfaces to help open it to the released position. The collet is retained by a removable member so that the collet can be removed and a broken tool shank extracted.