US 4,340,368 A · Dental handpiece or the like

Abstract

A hand held power tool, particularly of the type of a dental handpiece or the like is provided with power shut-off means disposed directly within the handle. The shut-off means is mechanically connected with a suspension means for suspending the hand piece or the like power tool such that the weight of the tool shuts off power supply to the tool. In a particularly preferred embodiment, a dental handpiece is disclosed wherein the suspension means is a magnet, whereby the handpiece can be suspended on any ferromagnetic surface without having to reach to a suspension fork which, in the known devices, is itself associated with a shut-off valve. The basic idea of the invention has broad application in many different fields of technology. The advance in the art, best represented by the dental handpiece, is an added convenience of temporarily suspending the handpiece at a place remote from the suspension fork which often is inconvenient to reach, while achieving the power shut-off without having to manipulate any further control means.

Claims23

Dependent claims

A dental handpiece assembly of the type including:

(a) an elongate handle provided at one end thereof with dental burr mounting means for releasably securing a dental burr to said handle;
(b) burr drive means for rotating a burr secured in said mounting means;
(c) drive shut-off means for selectively shutting off rotary motion of a burr mounted in said mounting means;
(d) suspension engagement means for suspending said handle on a support and secured to said handle to form a generally integral unit therewith but being movable relative to the handle within predetermined limits of movement, said engagement means being adapted to move to one of said predetermined limits due to the weight of the suspended handle when the handpiece assembly is not in use;
(e) mode control means for selectively maintaining said shut-off means in one of its "on" or "off" modes;
(f) said mode control means being operatively associated with said engagement means such that the limits of movement of said engagement means corresponds to the respective modes of the mode control means, said "off" mode corresponding to the limits obtained on suspension of said handle.

3 more elements

A hand held power tool assembly of the type comprising, in combination:

(a) a housing unit having a tool at one end thereof and including handle means generally integral with said housing unit and adapted to manipulate said tool;
(b) a power source associated with power communication means communicating said source with said tool for activating the latter;
(c) suspension engagement means at one end of said housing, for engaging a support thus rendering the tool suspended when not in use;
(d) said suspension engagement means being generally integral with said handle but being movable relative thereto within predetermined limits of movement, the engagement means being so arranged relative to said housing and/or said handle that on suspension of the handle, the engagement means is caused by the weight of said handle and/or said housing to reach one of said limits of movement, said engagement means being operatively associated with said power source and/or with said power communication means to discontinue supply of power to said tool when the engagement means reaches said one of said limits of movement;
(e) reversal means of the type of a resilient member for moving said engagement means to the other limit of movement when the engagement means is disengaged from a support, to thus activate said tool;
and
(f) said engagement means including a magnetic surface disposed exteriorly of said housing and/or handle, whereby the power tool can be suspended on a ferromagnetic surface.

4 more elements

A hand held power tool assembly of the type comprising, in combination:

(a) a housing unit having a tool at one end thereof and handle means generally integral with said housing unit and adapted to manipulate said tool;
(b) a source of electric power associated with electric power conductor means communicating said source of electric power with said tool for activating the latter;
(c) suspension engagement means for engaging a support thus rendering the tool suspended when not in use;
(d) said suspension engagement means being generally integral with said handle but being movable relative thereto within predetermined limits of movement, the engagement means being so arranged relative to the housing and/or said handle that on suspension of the handle the engagement means is caused, by the weight of said handle and/or said housing, to reach one of said limits of movement, said engagement means being operatively associated with shut off switch means disposed within said electric power conductor means to shut off supply of power to deactivate said tool when the engagement means reaches said one of said limits of movement;
(e) reversal means of the type of a resilient spring member for moving said engagement means to the other limit of movement when the engagement means is disengaged from a support, to thus activate said tool;
and
(f) said engagement means including a magnetic surface disposed exteriorly of said housing and/or handle, whereby the power tool can be suspended on a ferromagnetic surface.

4 more elements

Dependencies are inferred from the claim text.

Dental handpiece or the like

Life of this patent

Dental handpiece or the like

Life of this patent

Abstract

Claims23