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:
Nov. 07, 1995
Filed:
Aug. 19, 1994
Applicant:
Inventor:
Thomas Bierbaum, Lorsch, DE;
Assignee:
Siemens Aktiengesellschaft, Munich, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
A61C / ;
U.S. Cl.
CPC ...
433 84 ; 433114 ;
Abstract
A dental handpiece has a coupling member in which a passage for delivering a coolant to a discharge nozzle at the head part is provided. In order to prevent a flow-back of contaminated fluid with bacteria past the handpiece, a check valve is provided and comprises a check valve member disposed in a recess that extends radially inward from an outer surface of the coupling member and receives a flexible portion for closing a portion of the passage. The flexible portion is such that when the fluid is turned off, a suction in the fluid line will cause the flexible member to be pressed against the base of the recess and to prevent dripping from the exit nozzle.