US2314117A - Shielded rotary toothbrush - Google Patents

Description

March 16, 1943. D, s, BECKNER 2,314,117

SHIELDED ROTARY TOOTHBRUSH Filed Jan. 27, 1941 I/wnvrop, Omoar J, Bax/v52,

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Patented Mar. 16, 1943 UNITED STATES PATENT OFFICE 2,314,117 SHIELDED ROTARY TOOTHBRUSH Dwight S. Beckner, Rushville, Ind. Application January 27, 1941, Serial No. 376,108

2 Claims.

This invention relates to means for brushin and cleaning teeth in ones mouth by means of a power driven brush. A primary object of the invention is to provide a rotary driven brush which may be employed in the mouth to brush the upper teeth downwardly from the gums and the lower teeth upwardly from their gums and at the same time guard the inner cheek wall from contact by the brush.

A still further important object of the invention is to provide not only the above indicated guard means but also to incorporate with the guard and brush, means to hold and present a quantity of dentifrice to be picked up by the brush when it is being operated.

A still further important object of the invention is to provide in such means as above indicated, a brush and guard structure that may be supported by a head in such manner that other like brushes and guards may be employed to the end that a common head may be employed by all members of a family with an individual guard and brush set for each member of the family.

These and many other objects and advantages of the invention will become apparent to those versed in the art from the following de scription of one particular form of the invention as illustrated in the accompanying drawing, in which Fig. 1 is a view in side elevation of a structure embodying the invention in partial section;

Fig. 2, a top plan view thereof with one of the walls of the head broken away;

Fig. 3, a detail in longitudinal central section through the guard head;

Fig. 4, an end elevation of assembly;

Fig. 5, a transverse section in Fig. 1;

Fig. 6, a transverse in Fig. 1; and

Fig. 7, a side elevation of a dentifrice capsule to be carried by the guard.

Like characters of reference indicate like parts in the several views in the drawing.

I form a head, generally designated by the numeral III, of such size and proportion that it may be conveniently grasped across the palm of the persons hand and contain a suitable driving motor of any nature, such as a spring motor or an electric motor, an electric motor H being herein indicated as the source of power. In

the guard and brush on the line 5-5 section on the line 6-8 this respect, the important feature is that there be presented a driven shaft I: through one end of the housing to releasably receive by its outer end in any suitable manner the end of the brush shaft l3. The shaft l2 may carry any suitable type of engaging means for this purpose in the nature of a chuck, a simple frictional type of chuck being herein indicated wherein the shaft l2 has a central axial conical bore entered from its outer end to form a tapered socket to receive therein the conical end ll of the brush shaft l3. The degree of taper of the socket and the end It is made to be such that the end It will be frictionally retained within the socket in the shaft l 2 sufficient to form a driving connection therebetween and yet permit the brush shaft I3 to be pulled outwardly for disengagement. Whatever type of motor ll may be employed, the shaft l2 driven thereby operates at a relatively low speed, not to exceed five hundred revolutions per minute, first, to prevent any harsh action on the tissues within ones mouth and, secondly, to prevent centrifugal action throwing off dentifrice from the brush to any great degree.

The brush shaft I3 is made out of any suitable material such as will have the required structural strength for mounting and carrying a. brush I5 'spirally formed around its outer end portion.

Furthermore this shaft I: should be resilient in nature, at least to some degree. It is desirable to have this brush formed in such manner that the outer end, as indicated in Fig. 4, will have bristles presented thereacross so as to completely conceal the end of the shaft l3. The overall diameter of the brush is made to be that which will conveniently fit and give satisfactory operation over the teeth. I find that anoverall diameter of the bristles of flv-eighths of an inch to be quite satisfactory for this purpose, particularly for adults.

To one side of the brush I5 is positioned a guard or shield It by means of a resilient stem l'l extending substantially parallel to the shaft l3 and having an end releasably entered into and frictionally retained by a socket within the head I ll. Preferably the end l8 of this stem I1 is given some cross-sectional shape other than round, herein shown as rectangular, to prevent rotation of the stem I! about its axis. In addition to the cross-sectional shape to prevent rotation, this end I8 is preferably tapered so as to wedge itself into the socket in the head 10 for retention.

The guard I6 is positioned to be in close proximity but preferably not in direct contact with the outer ends of the brush bristles, Fig. 5, and the longitudinal marginal edges of the shield or guard terminate in a plane back of the axis of the complished by the shaft ii. In other words these marginal edges do not come around to the diametrical plane of the brush. Also in this guard 16 there is an outer overturned lip l9, Fig. 4, which will form a positive stop and yet at the same time will not interfele with the use of the end of the brush, particularly when the extreme rear teeth are to be reached.

' The guard I6 is also formed to have a longitudinal channel 20 presented along its inner side opening toward the brush. This channel 20 has an entrance opening 2| through the lip l9, Fig. 4. This channel 20 is provided to form a reservoir to contain a supply of dentifrice in any of the suitable and well known 'forms. A convenient way for charging the dentifrice into this channel is by means of a capsule 22, Fig. '7, having a water soluble wall and filled with the dentifrice in liquid form, paste form, or powder form. The diameter of the capsule 22 is made to be such that the bristles of the brush I will be in contact with it as the brush revolves so that, while the capsule wall is soluble itself, the action of the brush thereagainst, will quickly cause the wall to break down and release the dentifrice directly onto the brush so that the dentifrice is then available and distributed throughout the brush for application against the teeth.

Some dentists advise that the teeth should always be brushed by carrying the brush bristles along the teeth substantially vertically and away from the gums. This action is quite readily acinvention by reversing the direction of rotation of the shaft l2, which, with the use of the electric motor I I, is readily accomplished by simply reversing the motor in the usual and well known manner by means of a switch controlling set of buttons 23 and 24 conveniently located at the end of the head where they may be selectively operated by the thumb and index finger of the operator. The exact structure of the motor II and of the switch to be operated by the buttons 23 and 24 are not herein shown in detail for the reason that both are standard constructions readily obtainable on the market, and their details do not enter per se into the present invention. Thus by reversing the direction of rotation of the shaft l3, the brush I5 may be revolved in a direction to carry its bristles downwardly from the gums of the upper teeth, and then by operating the shaft in the opposite direction, the brush may be employed on the lower teeth to have the bristles moved upwardly from the lower gums.

As above indicated, by reason of the mounting of the shaft l3 and the stem l1, both of these members may be readily disengaged from the head and other like members substituted for them. This is entirely feasible in view of the fact that the brush and guard members are relatively inexpensive as to cost of manufacture. The

flexibility of the stem l1 together with flexibility of the shaft I3 make the device more convenient in use to apply the desired pressure against the teeth and at the same time prevent damage and injury. Furthermore, by means of this relative flexibility of the two members, the shield or guard l6 may be pressed closer to the brush I! at times, particularly in order to pick up residual quantities of the dentifrice within the shield.

While the invention has herein been described and shown in the one particular form in more or less minute detail, it is entirely obvious that structural changes may be employed, such as the particular shape of the dentifrice retentive and charging means, the shape and design of the head itself, and the particular holding means for the guard and driving shaft, all without departing from the spirit of the invention and I, therefore, do not desire to be limited to that precise form beyond the limitations as may be Y imposed by the following claims.

I claim:

1. The combination with a head and a driving shaft journaled therein, of a brush; a resilient shaft carrying the brush; means interengaging the brush shaft with said driving shaft; a brush shield; said brush being free to be yieldingly shlftable laterally in respect to said shield; and means carried by said head to support said shield in close proximity to and along one side of said brush; said shield positioning means comprising a resilient shaft, one end of which is detachably received and held against rotation by the head.

2. The combination with a head and a driving shaft carried thereby, of a brush; a resilient shaft carrying the brush; means interengaging the brush shaft with said driving shaft; a brush shield; said brush being free to be yieldingly shiftable laterally in respect to said shield; means carried by said head to support said shield in close proximity to and along one side of said brush; said shield carrying means comprising a resilient shaft, whereby brush may be laterally shifted one in respect to the other and also collectively in respect to the axis of rotation of said driving shaft; and means carried by said shield for holding dentifrice to be distributed by said brush whereby the brush and shield one in respect to the other will effect the removal of the dentifrice from said holding means.

DWIGHT S. BECKNER.

both the shield and the shifting of

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