US2195555A

US2195555A - Contra-angle dental handpiece

Info

Publication number: US2195555A
Application number: US139132A
Authority: US
Inventors: Harold H Beardsley
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-04-27
Filing date: 1937-04-27
Publication date: 1940-04-02
Anticipated expiration: 1957-04-02

Description

April 2, 1940. H. H. BEARDSLEY' CONTRA-ANGLE DENTAL HANDPIEGE 2 Sheets-Sheet 1 Filed April 27, 1937 1 Magi April 2, 1940.

H. H. BEARDSLEY CONTRA-ANGLE DENTALv HANDPIECE 2 Sheets-Sheet 2 rrr/67431441514.

Filed April 27 1937 l l BY PER

Patented Apr. 2, 1940 UNITED stares l rarest orrics 2,195,555k l f u i .y

u CONTRA-ANGLE DENTAL HANDPIEVCE Harold H.' lvearilsley, Denver, Colo." Application April v2&7, 1937, seriai No. 139,152

9 clams.` (ci. 52m-2n' This invention relates to improvement indental contra-angle hand pieces and particularly mission of the burr shanky thereinto and for clamping the burr shank in operative position., and (d) providinga rotating clamping means vhaving a smoothexterior. v

' With'these` and other objects in View, as willy hereinafter more fully appear, my invention comprises certain novell constructions, combinations and arrangements of parts as described in the following specification and dened in the appendedclaims and illustrated in the accompanying drawings in which:

Fig. 1 is a side elevation of a complete contra-angle hand piece rconstructed according to my invention. A l

Fig. 2 vis an enlarged fragment of Fig. 1. partly in elevation but mostly in vcentral section illustrating the contracting sleeve in clamping position.A

Fig. 3 is a sectional View on line 3--3 of Fig.'2 looking in the direction of the arrows but not includingthe burr and showing thel contracting sleeve in released position.

Fig. 4 is an elevation showing detail chuck in Figs. 2 and 3, forftapered burr shank.

Fig. 5 is a section on line 5-5 .of Fign4 looking in the direction of the arrows.

Fig. 6 isa detail view of a burr with parallel` sided shank.

- Fig. 'Tis a longitudinal section ofa modified closed Atherein as now in common use, suchA handle, including the enclosed parts, being generally indicated at H. Such a handle carries a tubular member I which, in turn, carries head housing 2, here illustrated 'as integral with the tubular member l. Within member. 4I is the 55 usual operating shaft 3 carrying suitable gear 4 ofthe which mesheswith gear 5 carried by hub having.v shoulder 1 Vwhich bears on a suitable bearing within housing 2 such as' the innerend of sleeve 8 threaded intok housing 2 and provided withl a head 9 for operation thereof andfor Alimiting its movement into the housing.

, Hub 6 carries an axially positioned chuck I havingan axial bore II for accommodationof the shank` cfa burr;v The bore II and'shank I 2 of the burr are vco-mating and may be tapered as illustrated in Figs. 2 and 3. The chuck lil is `reducedas at Illa and terminates in a frustoconical bearing IIlband is provided with a collar Ic. f

The lower or outer end of thev chuck l0 is slit as at |13 to formwspring fingers Ill and-these iingers are preferably provided with projections.

rotation'ofthe shank' with the` chuck will be insured but to insure such rotation even in case of inaccurate construction, positive means to secure such rotation may be provided as flat'. faced extension I1 ci the shank and stop I8on the inner wall 'of bore II so positioned Athat it will ybe encountered by extension I'I` in case of any rotative slip of shank I2 in bore II.,-

It wil1`be understood that shank I2 isrto be inserted in bore II `untill it fits snugly therein and projectionsll are so positioned as to engage shoulder I6 when shank I2 is thus seated and fingers I4 have been contracted. `'Accordingly taperedy shank I2 will be snugly seated in'v tapered bore II and will be positively held againstlongitudinal movement outwardly fromthe chucky when ngers I4 are contracted as illustrated in Fig. 2.- Normally the fingersv I -if-fiare outwardly to a degree which permits the insertion and withdrawal -of burr shank I2 without obstruction by projections v,I5 so that in order to clamp the shank within the chuck as illustrated in Figure 2J means "'must'be provided for pressing the fingers I4 inwardly after the shank has been inserted in the` chuck. Such means must also, y

be capable of releasing such pressure, allowing 4 ngers I4 to resumetheir normal position when For thispurpose I provide a slidable contractingsleeve or ring I9 slidably enclosing the lower end of .chuck Ill and provided at its lower end it is desired to withdraw the-shank from the Suitable means as bevelled shoulder 2l, are provided for contracting lingers I4 and guiding.

the ends thereof into bore 2U Whensleeve ,I9 is forced up over the chuck I from position shown` in Fig. 3 to that shown in Fig. 2, f

22, the lever being fulcrumed at 23, in lug 24 here shown as carried by member I and housing 2. The ends 25 of lever 22 engage sleeve I9 in any suitable manner for permitting rotation of sleeve I9 While insuring longitudinal movement of the sleeve I9 with ends 25 of the lever when the lever is moved between the solid line position shown in Figs. l and 2 and the position indicated by dotted lines in Fig. 2 and shown in solid lines in Fig.v 3; Such means may consist of annular groove 26 in sleeve I9 to accommodate ends 25 of the lever 22 which endsare, for this purpose, preferably rounded as clearly shown at Fig. 1.

Bearing member 2l is threaded into housing 2, the-frusto-conical bearing IIlb being seated therein.

Normally ends 25 of the lever will retain sleeve I9 even when in unclamped position as 'shown at Fig. 3 so that inadvertent dropping of sleeve It' is provided against and sleeve I9 is normally automatically retained in position for insertion and clamping of the shank and loss of the clamping members is prevented. Two objections toa threaded clamping member, viz: the danger of misplacement or dropping of the member and the knurled or roughened surface provided on such member for turning the same, are therei fore obviated by my invention.

Furthermore the operation of my clamping and releasing structure is simplified and facilitated,

such operation being accomplished by the thumb or nger of the hand of the operator While holding the handpiece in usual manner.

` For burrs having parallel sided shanks as shown in Fig. 6, I provide a chuck of form shown in Fig. 7 which is the samev in principle of construction and operation as the chuck shown in the other figures, having the same slot I3 and spring iingers I4, with preferable projections I5. In this modied structure, however, I provide bevelled shoulder 2.8 on the shank and bevelled seat 29 in the bore of the chuck and recess 3i) for reception of flat facedexte'nsion `3I to insure rotation of the burr with the chuck.

In Figs. 8 and 9 I have villustrated modifications of structural details of my means for eX- erting a resilient grip on a burr shank having parallel sides. Withsucha shank, accurately seated in the chuck, it will be found unnecessary to have the spring fingers contracted for- Ward of the shoulder of the shank, a resilient grip on the parallel sides of the shankl being suihcient. In such case vthe spring fingers I4 may be formed With outwardly projectingportions such as 32 in Fig. 8 or 33 in Fig. 9. In

such case also the sleeve I9- is structurally modified so that when it is forced over the fingers I4 it will contract the

projections

32 or 33, as the case may be, thus forcing those portions of the fingers which are adjacent the sides of the shank to grip the Shank in a resilient grip thus minimizing the danger of loosening of parts due to vibration. v

.The smallness of `dental hand pieces and the parts thereof and the corresponding minuteness ofsorne of the elements should be kept in mind for clear understanding of this specification and the accompanying illustrative drawings. For example, projections I will perform their functions'if only 1%000 or even 1A000 of an inch in depth.

Other dimensions may be correspondingly mi- For moving sleeve I9 intoor out of the clampy ing position shown in Fig. 2 I provide a lever preferably of bell crank U form as indicated atnute.

While I have illustrated and described many detailsof vconstructionl do not wish to be restricted thereto because many changes in such details, within the spirit of my invention and the scope of the appended claims, will be obvious to those skilled in the art.

l. In a dental handpiece, in combination, a housing, a chuck rotatably mounted in the housing and adapted to receive a burr shank having a shoulder, the :shank-receiving end of the chuck being divided into a plurality of resilient 'members extendingfrom said end of said chuck inwardly beyond saidf'shoulder'when the shank is seatedin the chuck and means slidable over the ends' of said members fadapted to contract ysaid members and causesaid members to resiliently grip said shoulder and'a bifurcated bell-crank lever fulcrurned on' said housing with its Weight arms engaging said slidable means for moving said slidable means into and out of contracting engagement with said resilient members.

` 2. In a'v dental handpiece, in combination, a housing, a chuck rotatably mounted inthe 'housing and adapted to receive a burr shank having a shouldenftheshank-receiving end of, the chuck being divided into a plurality of resilient' members extending from said end of Said chuck inwardly 'beyond said shoulder when theshank is seated inthe vchuckand means slidable over the ends of said members adapted to contract-said membersvand cause said' membersvto resiliently grip said shoulderand a bifurcated bell-crank leverfulcrumed on said housing with its Weight arms engaging said slidable means for moving said slidable'means into and out of contracting engagement withv said yresilient rmembers but adapted to permit rotation of sai-d slidable means with said chuck.

3. In a dental handpiece, in combination, a housing, a chuck rotatably mounted in vthe housing and adapted t'o receive aburr shank having a shoulder, the shank-receiving end of the chuck being divided intoa plurality of resilient members extending fromsaid end of said chuck in- Wardly beyond said shoulder when the shank is seated in the chuck, projections on the inner faces of said resilient members and means, operable bya bifurcated'bell-crank lever vfulcrumed on the housing, slidable over the ends of said resilient members adapted to contract said members and bringY `saidrproj ectionsl intor engagement with said shoulder. if A 4. In a dental handpieca in combination, a housing, a chuck rotatably mounted ini the housing and adapted to receive a burr shank having ashoulderfA the shank-receiving end of the chuck beingdivldedinto a plurality of resilient memland a lever whose bers` extending from said end of said'chuck in# Wardly beyond said shoulder when the shank is seated in they chuck and means slidable overl the ends of said members adapted to contract said members and a lever whose Weight arm engages said slidable means and which is fulcrumed on said housing and adapted to move said slidable means into and out of contracting engagement with said resilient members. f

, 5. In a dental handpiece, in combination, a` housing. a chuck rotatably mounted in the hous` 6. In a dental handpiece, in combination, av

housing, a chuck rotatably mounted in the housing and adapted to receive a burr shank, the shankereceiving end of Said chuck being divided into a plurality of resilient members and means 1 slidable over said members and adapted to con. tract said members to resiliently grip said shank weight arm engages said slidable means and which is fulcrumed on said housing and adapted to move said slidable member longitudinally of the chuck but to permit rota. tion of vsaid slidable member with the chuck.

7. In'a dental handpiece, in combination,

I housing, Ya chuck rotatably mounted in the housing, means slidable over the shank-receiving end 4of said chuck, resilient nie'ansfoperable by said slidable means for gripping said shank when seated in the chuck and lever means fulcrumed on the housing'and Whose weight arm engages and is adapted vto longitudinally reciprocate said slidable means. v

l8.In` a dental handpiece,l in combination, a housing, a chuck rotatably mounted in thel housing, means slidable over the Ishank-receiving end of` said chuck, resilient means operable byksaid Islidable means for gripping said shank when seated in the chuck and lever means fulcrumed v on the housing and whose Weight arm has a peripherally slidable engagement with and is adapted to reciprocate said slidable means longitudinally While permitting rotation of said slidable means with the chuck. I

9. In a dental handpiece having a housing, a burr shank chuck rotatably mounted in the housing and clamping means moveable longitudinally of the chuck for clamping and unclamping the shank, a bifurcated bell-crank lever fulcrumed on the housing having Weight arms engaging the clamping means to move the said means longitudinally and permit the rotation ofA said means `With-the chuckwlien clamped thereon.

HAROLD H. BEARDSl'aEY.