US1476519A - Toothbrush - Google Patents

Description

Dec. 4 1923.

W. KARL ET AL TOOTHBRUSH Filed Nov. 10 7 Invnfors Patented Dec. 4, 1923.

UNITED STATES ream PATEN .OTFFWE.

WILLIAM KARL AND HEINRICH KARL, F JERSEY CITY, NEW J TOOTHBRUSH.

Application filed November 10, 1917. Serial K020136 14.

To all whom it may concern:

Be it known that we, IVILLIAM KARL, 'a citizen of the United States, and HEINRIOH KARL, a citizen of Germany, residing at 5 Jersey City, county of Hudson, State of New Jersey, have invented certain new and useful Improvements in Toothbrushes, of which the following is a specification.

The present invention relates to improve ments in toothbrushes, and has for its object to provide means by which the bristles of a tooth-brush may be protected against breakage at their points of connection to the handle or backing. At the same time this invention provides means by which the bristles would be impregnated, and thereby rendered more elastic and therefore more resistant to wear.

A further object is to provide a brush which will be moisture-resisting, so that the bristles will not absorb water. In this way the life of the brush will be materially increased.

With our improvements we further provide a brush which will have improved cleansing properties that is, it will polish and clean the teeth in a manner not possible with the ordinary tooth-brush.

IVith this and other objects in view em- 30 bodiments of our invention are shown in the accompanying drawings, and these embodiments will be hereinafter more fully described with reference thereto, and the invention will be finally pointed out in the claims:

In the accompanying drawings:

Fig. 1 is a side-elevation of a tooth-brush embodying our invention;

Fig. 2 is a horizontal sectional view taken along the line of 2-2 of Fig. 1;

Fig. 3 is a vertical sectional view taken along the line of 33 of Fig. 1;

Fig. I is a perspective view showing a device employed in manufacturing the brush of our invention;

Fig. 5 is a plan view of this device.

Fig. 6 is a perspective view of a tool for use in applying a compound used in constructing a tooth-brush embodying the invention, a portion of the brush being shown in dotted lines; and r Fig. 7 is a side elevation of a brush 'enr bodying a slightly different form of the invention.

imil r re rence charac ers indicate corone, and at the same time to hold the compound securely with relation to the bristles.

The compound 22 must have certain characteristics: for instance it must not be injurious to the teeth or gums. It cannot, therefore, be a very hard substance but must on the contrary be quite soft. The degree of softness of the compound is preferably such as to cause it to wear slightly when the brush is in use. As one embodiment we propose to employ para rubber, which is ofa very soft, and at the same time elastic and fiexible, character. Of course other materials which do not contain ingredients injurious to the teeth may also be employed.

vVe propose to mix rubber with particles of cord or cork-dust .or other material which will not be injurious to .the teeth. In' some cases it may be preferable to apply two or more layers 35, 36, and 37 all of different substance, and in such caseswe may provide as the top layer 37 para rubber which has a property of constituting polishing meansfor the teeth.

While we have shown an elastic and flexible compound, as extending a short way along the bristles, it will be understood that it may be only a thin layer extending slightalmost to the end of the bristles leaving only the points free.

The bristles may be impregnated with oil 7 or other moisture-resisting substances prior to the application of the compound to them, especially if the compound which isto be 1y above the base or it may, if desired, reach applied, consists of rubber, but we may pro- 7 vide a compoundor compounds which are themselves mixed with a suitable oil. In the case last mentioned, the oil or the compound may be caused to impregnate the bristles in a very thorough manner thus rendering a special impregnation of the bristles unnecessary, A special impregnatlonof the br t es.

I bemoisture-resisting and the bristles will not become water-soaked.

We know that it has heretofore been proposed by others to use certain materials such as cement and rubber, the latter beingusually vulcanized, for holding the bristles of a brush firmly in the backing. Inasmuch, however, as the substance thus used were intended to serve only to secure the bristles to the-backing, theywere so arranged as in reality to form merely a molded portion of the backing, and even when the compounds composed of rubber were made hard, as by vulcanization, they became injurious to the teeth or gums if brought in contact with them when using the brush. The compounds employed by us act on the other hand not only to prevent breakage of the bristles, but also to provide a polishing medium for the teeth,.and other purposes for which the construction of the prior art are not adapted.

Accordingly the compound or compounds used by us are located on different parts of the bristles from the molded-backing-members proposed by others, and possess characteristics different from those of such backing members.

In carrying out our invention it will be understood that any suitable material having the properties desired may be employed,

but preferably these should be such that they Y will not have abad taste, as well as not be injurious to the teeth.

With our improvements it will be seen that the bristles are supported by means additional to those usually employed on toothbrushes, and therefore applied to parts of the bristles which on other tooth-brushes are left free. The grip upon the bristles and the protection afforded them is therefore such that danger of the bristles breaking off or pulling out is entirely obviated. In the old forms of brushes, the bristles would very soon break off after very little use, the breaking occurring usually at their base, this being the result of the bristles becoming too brittle.

In our invention the bristles may be sufliciently stifi to properly cleanse the teeth, and at the same time they are so flexibly supported that they will not break off.

It shoud also be mentioned that the oiling alone will not -suiiic'e to render the bristles continuously elastic and therefore resistant to breakage, -tastier se the oil will "be gradually The compound 22 may be applied in various ways, the one herein employed consisting in the use of a tool shown in Figs. 4 and 5, and another tool constructed as shown. in Fig. 6.

In order to apply the compound 22 in a A neat manner, a tool such as shown in Figs. 4 and 5 may be employed. This tool shown in Figs. t and 5 consists of a sheet of metal 10 having a slit 11 adapted to embrace the bristles, the side portions of the sheet being bent upwardly and inclined oppositely from each other. The bristles, of the brush are placed in the slit and held together, whereby the compound 22 will be confine-d to its proper shape. The tool shown in Fig. 6 comprises a sheet 30 of metal sharply bent midway its side edges, as shown at 30 and having a slit 30 which extends a portion of its length. I

This tool is used for applying the (10mpound 22 between the rows of bristles, and between the individual bristles as illustrated in Fig. 6 whereby the bristles are divided by the portions of the sheet 30 and the compound 22 will be poured or placed in the space between the two upwardlybent in clined portions and 30 of the device. A slight pressure will force the compound through the slit 30 and cause it to contact with the base portion of the bristles and with the backing. This method of applying the compound prevents smearing of the tips of bristles with the compound, and by turning the tool horizontally, soiling o-f'the outer portions of the bristles by the compound, will be avoided;

e have illustrated and described a preferred and satisfactory embodiment of our invention, but it is obvious that changes may be made therein within. the spirit and scope thereof as defined in the appended claims,

and that the invention may be embodied 2. In a tooth-brush, a base, bristles set in said base, a latterly disposed cord entwined about said bristles adjacent said base, and an elastic compound disposed upon said base, and imbedding said bristles adjacent their ends set in said base and gripping said cord, and constituting a flexible strengthening means adapted to prevent breaking ofl of the bristles set in said base.

3. In a tooth-brush, a base, bristles set in said base, and an elastic compound having a finely divided polishing substance mixed therein, said elastic compound disposed upon said base and imbedding the bristles adj acent their endsset in said base, constituting a flexible strengthening means adapted to prevent breaking off of said bristles adj acent said base.

4:. In a tooth-brush, a base, bristles set in said base, an elastic adhesive compound disposed upon said base, embedding the bristles for a portion of their length between their base portion and their tip ends, said compound servingto support the bristles yieldingly adjacent their base portion to prevent breaking of the bristles, the bristles being also impregnated with oil to make them resistant to the absorption of Water, and to render them less brittle.

5. In a tooth-brush, a backing, a compound disposed upon said backing embedding the bristles between the base and the points thereof for holding the bristles straight and rendering them resistant to breakage, and another compound disposed upon said firstmentioned compound and being mixed with cork particles constituting a harmless cleansing and polishing means for the teeth in co-operation with the bristles.

WILLIAM KARL. HEINRICH KARL.

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