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. 04, 1991
Filed:
Oct. 26, 1989
Garfield R Lunn, Amherstburg, CA;
Arvid Machine Tools Ltd., Windsor, CA;
Abstract
A tool shaft is supported for rotation about a vertical axis by means of upper and lower bearings. A motor drives the shaft at least at 500 rpm. A gap is formed radially between the shaft and an adjacent stationary member, the gap extending from one bearing to the other. A reservoir which contains lubricating oil communicates with the gap to supply oil thereto to cool and lubricate. The tool shaft carries a helical thread disposed within the gap which pumps the oil upwardly through the gap and through the bearings to create a hydrostatic bearing for the shaft segment extending between the bearings. The tool shaft is driven by a gear shaft which also is provided with a hydrostatic support by means of oil pumped through a radial gap by means of helical threads which are stationary, but which are disposed closely adjacent a surface of the gear shaft.