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:
Mar. 16, 1989
Akio Yamada, Tokyo, JP;
Fumio Hayashi, Tokyo, JP;
Ishikawajima-Harima Heavy Industries Co., Ltd., Tokyo, JP;
Abstract
A rotating speed control system for a pneumatically driven spindle used in a machine tool, comprises a spindle possessing a male-threaded part, a turbine mounted on the spindle by a nut with a convexo-concave portion being formed in one face thereof, a casing for accommodating the spindle and the turbine, an air supply line connected to the casing so as to supply air to drive the turbine, a valve disposed in the air supply line so as to adjust the flow rate of the air to be supplied to the turbine, a sensor facing the convexo-concave portion of the nut so as to detect the rotating speed of the turbine, and a control circuit for comparing a sensor detected rotating speed with a predetermined rotating speed and for adjusting the valve in accordance with the difference between two rotating speeds, so as to reduce the difference.