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:
Oct. 22, 1996
Filed:
Jul. 21, 1995
Juergen Wohlgemuth, Darmstadt, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A dental turbine drive contains a rotor disk which is mounted for rotation in a rotor chamber in a head housing of a dental handpiece and is driven by compressed air from a nozzle in the known way. A control element for regulating the speed is arranged in the flow path of the exhaust air and is constructed to change shape or position upon rotation of the rotary disk as a consequence of centrifugal force so that the effective cross section of the exhaust path decreases with increasing speeds and will increase with decreasing speeds. In addition, an additional or second element is provided and includes a pressure chamber connected by channels to the rotor chamber so that the additional element will respond to changes in the pressure in the rotor chamber to support the effect of the control element. The second element can be a diaphragm valve having a valve member extending into either an exhaust channel or a delivery channel. The additional or second element can be a disk coacting with a resilient ring of the control element to form the control chamber in a recess on the rotor which receives the control element.