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:
Dec. 24, 1991
Filed:
Feb. 26, 1991
Takasuke Nakanishi, Kanuma, JP;
Nakanishi Dental Mfg. Co., Ltd., Tochigi, JP;
Abstract
A device for preventing intrusion of foreign matter into a dental handpiece includes an end cap secured to a bur sleeve for rotation in unison with the bur sleeve. Around the end cap, there are delimited gap sections the one end of which communicates with a forward or lower ball bearing positioned towards a tool inserting opening and the other end of which is opened at the foremost part of the handpiece. A discharge port passing through the main body of the handpiece and communicating with the gap sections is formed at the foremost part of the handpiece. With rotation of the bur sleeve, the end cap is rotated so that the pressure within the gap sections is decreased to suck the foreign matter, such as cut tooth particles or chips, which is expelled to outside through the discharge port under the centrifugal force of the end cap.