US2242743A - Toothbrush - Google Patents

Description

May 20, 1941. w ow 7 2,242,743

TOOTHBRUSH Filed May 15, 1959 M1 I f iiiiiiliii I Patented May 29, 1941 TOOTHBRUSH Donovan W. Brown, Huntington, Ind., assignor of one-half to Joseph T. McCarthy, Uhicago, Ill.

Application May 15, 1939, Serial No. 273,619

6 Claims.

This invention relates to an improvement in toothbrushes, and more particularly to the arrangement and construction of the bristles of the toothbrush.

One object of my invention is to provide a toothbrush, the bristle tufts of which tend to adapt themselves to the contour of the surfaces of the teeth, and which readily reach into the irregularities found on the surfaces of the teeth as well as the spaces between them.

Another object of my invention is to provide a toothbrush which assists the user in the proper brushing of the teeth.

Another object of my invention is to provide a toothbrush which readily adapts itself to the contour of the surfaces of the teeth, and which enters the irregularities and spaces found between the teeth with the minimum amount of pressure, thus lengthening the life of the bristles.

A more specific object of my invention is to provide a toothbrush having a working surface comprising a series of transverse inverted V- shaped grooves, each constituted by oppositely beveled upper surfaces of bristle tufts secured at an angle to the brush handle and crossing each other intermediate their ends.

Other objects and advantages of my invention will appear more fully from the following description, during the course of which reference is made to the accompanying drawing, in which:

Fig. 1 is a side elevational View of a toothbrush embodying my invention, showing the bristles of the brush in contact with a dental arch;

Fig. 2 is a side elevational view of a toothbrush is indicated in its entirety by reference character I0. It may be seen to comprise a handle portion l2, preferably made of rigid material in accordance with customary practice. The forward orhead portion 14 of the handle has secured to it a plurality of outwardly extending tufts l8 of suitable bristles. The head l4 may be dimensioned and shaped to suit the user or manufacturer, and this is true to a certain extent of the bristle tufts IS.

The bristles are constructed and arranged on the head of the brush to provide a series of transverse, broad, inverted V-shaped areas on the working surface, as indicated by the reference character l8. Furthermore, the bristles are arranged at an angle with respect to the brush head and handle so that when working pressure degrees, and the obtuse angle as approximately degrees. These values are the preferable values, and they may be varied somewhat. The tufts are so located with respect to each other that they cross intermediate their ends, and the outer ends are beveled in a manner now to be described.

The working ends of the tufts are beveled to provide the inverted V-shaped working areas previously referred to. Theends 24 of the tufts inrow 20 are beveled. toward thehandle 12 and theends 26 of the tufts inrow 22 are beveled in the opposite direction, that is, away from the handle. In other words, the bevel may be considered to be in a direction opposite to the direction in which the tuft slopes. The bevels are so designed that the acute angle between the surfaces thereof and a plane passing along the topmost part of the tufts is approximately 25 degrees. The angle included in the V is thus approximately 180 minus 50 or degrees. Here again the values given are the preferred values and may be varied.

The many advantages of the brush of my invention may perhaps be best noted from a consideration of the action of the brush when utilized in brushing the teeth. Referring first to Fig. 1 wherethe brush is illustrated in light contact with the dental arch, it may be noted that the transverse V-shaped grooves are so dimensioned that they fit the tooth contours with considerable accuracy, and that when pressure is applied to the brush, the bristles bend and slide along the surface of the teeth and reach into the irregularities in the individual tooth surfaces and in between adjacent teeth. The pressure required to force the bristles into the position indicated in Fig. 2 is relatively light, because the bristles bend and slide along the surfaces of the teeth. One of each pair of tufts defining an inverted V-shaped groove move in opposite directions. The construction, therefore, eliminates crinkling of the bristles and provides a more perfect working contact by slight bending of the individual bristles of each tuft.

The construction of the toothbrush with a series of relatively broad, transverse, inverted V- shaped grooves facilitates correct brush manipulation when the Charters method of brushing is used. This method, as well known to those skilled in the art, comprises moving the brush up and down.

Maximum cleansing is provided by the angular relation between the tooth surfaces and the bristles, and the bristles adapt themselves to surfaces which are irregular or uneven with a minimum of pressure. A longer brush life is insured because of the slight amount of pressure required and the resulting decreased strain on the bristles. The decrease in pressure likewise eliminates crinkling of the bristles.

The brush also guides itself into the areas needing brushing; that is, the spaces between the teeth and the hollows or irregularities on the surfaces of the teeth. A further advantage of the brush is that the tufts spread out freely during use, thus creating a larger working area.

The above-described embodiment of my invention has been included herein for the purpose of illustration only, and modifications thereof may occur to those skilled in the art. Among these modifications may be mentioned the variation of the angle of the tufts with respect to the brush and the angle included in the transverse grooves. As a matter of fact, certain advantages of my invention may be realized without providing any transverse grooves whatever. Furthermore, instead of having two rows of bristle tufts, a greater number of rows may be utilized.

What I claim as new and desire to secure by United States Letters Patent is:

1. A toothbrush comprising handle and head portions, parallel rows of bristle tufts secured to said head portion and projecting outwardly therefrom, the tufts in one of said rows being secured to the head portion at an acute angle with respect to said handle portion, and the tufts in another row being secured to said head portion at an obtuse angle with respect to said handle, and the outer end of each of said bristle tufts being beveled inwardly in a direction opposite to the direction in which the tuft slopes at an angle such that the working surface is at an acute angle with respect to a plane passing along the outer extremities of the tufts.

2. A toothbrush comprising handle and head portions and parallel rows of bristle tufts secured to said head portion, the tufts in one of said rows being secured to said head portion at an angle opposite to that at which those in a second row are secured to the said head portion, and each tuft in one row crossing a tuft in another row longitudinally of the brush and intermediate the ends of the tufts, and the outer ends of said tufts being beveled in directions opposite to the slope of the tufts to define working surfaces located at acute angles with respect to a plane passing along the outer extremities of the tufts.

3. A toothbrush comprising a handle portion and a head portion, bristle tufts mounted on said head portion providing a working surface consisting of a series of transverse, inverted V-shaped grooves, each groove comprising the tips of a pair of tufts secured at an angle to the brush and crossing each other intermediate their ends, the tips of said tufts being beveled oppositely across the entire widths thereof.

4. A toothbrush comprising handle and head portions, and parallel rows of bristle tufts secured to the head portion and projecting outwardly therefrom, the tufts in one of said rows being secured to the head portion at an acute angle with respect to said handle portion and the tufts in another row being secured to said head portion at an obtuse angle with respect to said handle portion, the outer end of each of said bristle tufts being beveled in a direction opposite to the direction in which the tuft slopes to define plane working surfaces disposed at angles of approximately 25 degrees to a plane passing along the outer ends of the tufts.

5. A toothbrush comprising handle and head portions, and two parallel rows of bristle tufts secured to the head portion and projecting outwardly therefrom, the tufts in one of said rows being secured to the head portion at an angle of approximately degrees with respect to said handle portion and the tufts in the other row being secured to said head portion at an angle of approximately degrees with respect to said handle portion, the outer end of each of said bristle tufts being beveled in a direction opposite to the direction in which the tuft slopes to define plane working surfaces disposed at angles of approximately 25 degrees to a plane passing along the outer ends of the tufts.

6. A toothbrush comprising handle and head portions, and two parallel rows of bristle tufts secured to the head portion and projecting outwardly therefrom, the tufts in one of said rows being secured to the head portion at an angle of approximately 65 degrees with respect to said handle portion and the tufts in the other row being secured to said head portion at an angle of approximately 115 degrees with respect to said handle portion, each tuft in one row crossing a tuft in another row longitudinally of the brush and intermediate the ends of the tufts, and the outer end of each of said bristle tufts being beveled in a direction opposite to the direction in which the tuft slopes to define longitudinally spaced apart plane working surfaces disposed at an angle of approximately 25 degrees to a plane passing along the outer ends of the tufts.

DONOVAN W. BROWN.

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