US1774031A - Rotary toothbrush - Google Patents

Description

Aug 26, 1930 c. MCLELLAN 1,774,031

ROTARY TOOTHBRUSH rusa July 13, 1929 Patented Aug. 26, 1,930

a (Hermanns MnnnLAN, ors1oux.c1'rY,-Iow.a

j ROTARY 'roo'.rBBRUsn Appiieation ined Juiyr' 13, 1929. A' Serial No. erases'.

Myinvention relates to rotary toothbrushes and has for its object to provide a toothbrush of simple, durable and inexpensive construction. f

5 The invention ving a casingiproviding ahood .for covering a portion Vofthe brush and a handletobe grasped by the hand of the operator, abrush ournalled-in the handle anda knob tobe engaged by the vtingersoic. the operator'for rotating the brush.

As already stated, itis my purpose to `provide a construction asv inexpensive as possible. However,

element in a brush of this charactennamely, the possibility of removing and replacing the brush per se from the casingwhich holds To this end, my invention contemplates providing av device in which the brush is embodied in a detachable'unit comprising the brush and afshank byy means of which the brush may be attached to the knob.

A A further 'object ofmy invention "necessarily resultingv from the labove mentioned Objectis' that'or` providing ,ank arrangementbrushand knob may be attachedtogether in connection with the handle which in v`whi ch Ythe supports them insuch a way `that-they are journalledv within the handle. for rotation. Atthe same time, itzis an arrangement in whichlthe att-achinggor detaching of thebrush/may be accomplished in a very simple manner. To this end,my invention contemplates .the use of a snap linkdriving connectionbetween the brushand the knob andthe hiding of said driving connection within the handle of the brush. T v

`A further object to 'provideA a ldevice ofy 40 the above characterjin which the ysnap* driving connection betweenthe two rotating; elements of the brush` is not required tosustain the burden of? supportingl thefbrushk and knob in axial alignment with 'each other. i To this a end, my invention rproposes .to utilize the han,-v

is embodied in a d'evicefhavanother feature is avery important `template'd are attained, as hereinafter more 'and parts lbeing' shown y 'illustrate lthel construction.

my purpose to provide f and dle as a bushing'to support rotatable shaft portions of the brush and knob, respectively,

the shaft portions both: beingV oflsncient -length to give the required-'support andthe :snap drivlng'y connection being interposedV 'therebetween and-'positioned intermediatethe ends of the handle.

`Another object of my invention, is tovf'provide a` brush whichis particularly adapted tov be cleaned and kept in asanitary condition.v

With these and other objects in view, my

"invention" consists in thel construction, ar-

rangementland combination of the various parts of my device, wherebythe objects con- Fig. 2 is a longitudinal, sectional view of a thebrush. *i v Fig. 3 is ay similarl sectional vview ofthe -rotating assembly, the 'bruvshrbeing omitted irl-elevation to further Fig. 4 is an end `view ofthe brush shank. Fig. l5 is an 'end view of the brush shank viewed from the socket end. Y' l Fig. Gais an end view of the knob viewed from its'vshaft end. n s f* l 7-is`an end view of the assembledv brush `Fig.` 8 isa detaiL'section'al view showing a ymodified form of'snaplink connection. v

Ihave 'used' the reference character 10 to indicate-l i generally lthe i casing of the f device which is constructed in one integral piece't'o form ahoo'dv 1-1 and a handle or barrel 12.`

The Qbarrelis provided 4with an axial bore,

whichisfsuiiciently smooth toform a bearing surfacefor the rotating parts.A Between the hood 11, and barrel 12 is `formed i asquared shoulder `13, jwhich may beconsidered 'asv one y 1 the barrel 12.v

end of the barrel 12, the other end also being squared as shown.

The brush unit comprises a cylindrical brush 14:, which is provided with the central core yor spindle 15, on which the bristles of the brush are mounted. The spindle 15 projects from one end as at 16, where it is received in the shank 17 Vof the brush, which is cylindrical in form and sized to fit smoothly within thebore of the barrel 12.

The shank 17 is provided at one end with an enlarged collar` 18, formed integrally with the shank and-adapted to engagethe shoulder 13 of the barrel l2.

At its other end the shank 17 is provided with a' socket 18a, which is preferably polyhedral in construction, as shown in Fig. 5. The end of the shank 17 is split'as atV 19 to forml two socket jaws 20, the .slotl 19-allowing the jaws to spread.

Thejaws 20 are also cut away as at 21 so that the cross sectioned area within the circumference of the outeredgesv of the jaws is less than theV cross sectional area-of the interior ofthe barrel`l2. The objectof thus reducingithe jaws is to allow them to spread within the barrel 12.

The knobA 22 is formed integrally with a knob shaft V23,y which-also is shaped to smoothlylitl within the'bore of the barrel 12. A shoulder 24de formedybetween the shaft 23 and knob 22, which engages the free end of The end. ofthe shaftf23fopposite the knob 22 is providedwith a teat 25, which is shaped to, fit snugly'within the socket 18; The socket w18 and teat 25'are formed withoneor more inclined sides, thus enlarging their cross sectional area near theinner extremity of the socket and near the endo'f the teat.

The teat is providedL with a bevelled' end face 27, which spreads the jaws 2O to allow Ithe teatto-enter the socket.v It will now be seen that a'snap construc tionis provided, `which not onlyacts as a driving connection between the two rotatable members, but also serves to hold them together'against pulling apart. At the same time, when sufficient pullis exerted against the'inembers by the hands of the operator, they may be separated for the purpose ofreplacing a brush or for cleaning,

It will be under stood that the ordinary person using a brush ofthis kind will wish to clean'the brush, at least tovrinse it,'after ,each period of use. For this purposeit will be desirable to' separate the parts and to wash orrinse ,them individually. Thus the brush is, much more sanitary than it, would be if the part-s were not readily separable.

j The shaft 23and shank17ua`re journalled withinthebarrel 12 so that/lateral support for the brushy and knob are provided. The

' snap connection'is thus relieved of' all lateral strainsand may thus' v'be constructed more each other from delicately and with much less length to the socket than would otherwise be necessary. The only functions of the snap connection are those of providing a. driving connection and yieldably holding the knob and brush together.

The shoulders 18 and 24 tend to prevent the entrance of moisture or foreign material into the barrel of the brush and thus assure smooth operation of the brush.

It will be understood that the snap construction might be any of several types. For instance, the construction shown inFig. 8 might be employed, wherein, instead of a teat that is approximately square in cross section, a flat vfinger 30 vmay be employed, adapted to enter a slot 3 1 in the end of the shank 17 and provided with a pair of lugs or the like 32, adaptedto enter depressions formed for them between the jaws 20a.

The advantagesof my invention reside in its sanitary features and inits simplicity and inexpensiveness. The combination vof the sanitary feature, the detachability ofA the brush unit and the simplicity and sturdiness of construction are believed to be novel in Vrotary toothbrushes.

Some changes may be made in the construction and arrangement of the parts of my invention without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms ofV structure or use of mechanical equivalents, which may be Areasonably included within their scope.

1 claim as my invention:

1. In a rotary tooth brush, a barrel serving as a handle, said'barrel having a longitudinal cylindrical bore extending therethrough, a brush',l a shank in which said brush is mounted, al driving member including a shaft and a knob, thea shank and shaft having cylindrical portions snugly journalled in the barrel, anda separable connection between the cylindrical portions, comprising projections on the ends of the respective cylindrical por.

tions extending longitudinally thereof into latching engagement, the projections having non-cylindrical faces in engagement with each other tov formv a driving connection between the cylindricalk portions, said projection'svbeing of resilient material and the said faces being inclinedulaterally outwardl from the cylindrical portions, so that the'projections must spring apart in order to move past latched to unlatched positions.A l

2. In a rotary tooth brush, a barrel serving asa handle, said barrel having a longitudinal cylindrical bore extending therethrough, a brush.,v al shank in which said brush is mounted', a driving member including a shaft and a knob, the shaft and shank being of resilient material land having cylindrical' portions journall'e'd in theb'arrel', the inner end of one f pulling apart under normal working condi' y of said cylindrical portions being split to form two separated members provided with a.

space between them that is non-cylindrical in cross-section and has a constricted mouth, and a teat formed on the other cylindrical portion, including an enlarged portion joined to the body of said other cylindrical portion by means of a reduced neck and receivable between said spaced members to form therewith a driving connection between the shank and shaft and to latch them together against tions.

Signed this 8th day of July, 1929, in the county of Woodbury and State of Iowan CHARLES MGLELLAN.

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