US 3263258 A
Description (OCR text may contain errors)
D. E. BUR G E TOOTHBRUSH Aug. 2, 1966 Original Filed May 22, 1961 INVENTOR. DAVID E. BURGE United States Patent 2 Claims. (Cl. -167) This is a continuation of application Serial No. 111,839, filed May 22, 1961, for Toothbrush, now abandoned.
This invention relates, generally, to brushes and, more particularly, to a brush having a new and improved construction. While the novel construction characterizing the present invention applies particularly to toothbrushes, it applies also to many other kinds of brushes.
In the making of, for example, toothbrushes, the use of synthetic bristles is known, and such bristles are frequently though not always formed of nylon, a synthetic linear polyamide. The reference to nylon bristles in the description to follow is for the purpose of illustration, the invention not being limited to blushes having nylon bristles.
Manufacturers of nylon-bristle toothbrushes have provided, in the past, a variety of toothbrushes designated soft, medium, and hard to indicate the stiffness of the bristles. Usually it is the diameter of the individual bristles that determines the stiffness, the soft bristles having a diameter of nine (sometimes eight) thousandths of an inch (9 gauge), the medium bristles having a diameter of twelve thousandths of an inch (twelve gauge), and the hard bristles having a diameter of thirteen thousandths of an inch (thirteen gauge). For all bristles, there is generally a manufacturing or grading tolerance of about $0005 inch.
An object of the present invention is to provide a brush of new and improved construction.
Another object of the invention is to provide a brush of which each tuft has bristles of different characteristics.
A further object of the invention is toprovide a new and improved brush adapted to be used as a toothbrush.
A brush constructed in accordance with the principles of the present invention comprises a body portion having a plurality of tufts attached thereto at spaced-apart intervals. At least some of the tufts have a plurality of bristles of different characteristics-for example, different degrees of hardness or stiffness.
In a toothbrush constructed in accordance with the principles of the invention, there are two or more groups or classes of bristles in each tuft, the bristles of one class having a diameter different from the diameter of the bristles of the other class or classes, so that some of the bristles are harder than others. In some instances, there are three classes of bristles in each tuft. The arrangement of the bristles in each tuft may be either symmetrical or ran dom, and the various degrees of hardness may be obtained by means other than a variation of the diameters or crosssectional areas of the respective bristles, as will appear from the following detailed description.
A complete understanding of the invention may be obtained from the following detailed description of two structural arrangements constituting specific embodiments thereof, when taken in conjunction with the appended drawings, in which:
FIGURE 1 is a fragmentary view in perspective showing the bristles arranged symmetrically;
FIGURE 2 is a view similar to FIGURE 1 but showing the bristles arranged at random;
FIGURE 3 is a diagrammatic perspective view showing a toothbrush constructed in accordance with the principles of the invention; and
FIGURE 4 is a diagrammatic illustration showingthe operation of the toothbrush shown in FIGURE 3.
In FIGURE 1 of the drawings, the numeral ltlindicates, generally, a back or body portion of an adult-size toothbrush. The body portion 10 has any suitable configuration, and, although it may be formed of any suitablematerial such as metal, wood, rubber, or plastic, it is preferably formed of plastic.
A plurality of tufts 11 are mountedlon the body portion 10 by, for example, insertion of one end of each tuft into appropriately-spaced recesses or sockets 12.. Each of the tufts 11 is formed of any desirednumberof bristles. Usually, however, a toothbrush has approximately nine bristles in each tuft.
It is an important feature of the invention that the. bristles forming each tuft be of different characteristics. As shown in FIGURE 1 of the drawings, each tuft 11 is formed of a first plruality of soft nylon bristles 13, a
second plurality of medium nylon bristles14, and a third.
plurality of hard nylon bristles 15.
The soft bristles 13 are nine gauge (nine thousandths. of an inch in diameter). The medium bristles 1.4 are twelve gauge, and the hard bristles 15 are thirteen gauge. The tufts are substantially free of bristles having. a diameter departing fro-m the various nominal values by more than .0005 inch which represents a manufacturing or grading tolerance.
In the embodiment of theinvention shown in FIGURE 1, the bristles in each tuft are arranged symmetrically with.
respect to each other. For example, the hard bristles 15 are positioned in the center, and the bristles 13 and 14 are arranged alternately around the hard bristles 15.
In the embodiment of the invention shown in FIGURE 2, the bristles are arranged at random. The numerals 13, 14, and 15 designate in FIGURE 2 bristles identical to the ones respectively identified by those numerals in FIG- URE 1.
By combining the bristles as described above, the soft bristles 13 remove materials from the crevices between the teeth of a user and around the gums. The hard bristles support the soft bristles so that the latter do not bend away from the surfaces of the teeth and thus become unavailable to penetrate the crevices. At the same time, the hard bristles effectively polish the surfaces of the teeth.
A toothbrush having tufts of entirely hard bristles or medium bristles fails to penetrate certain of these crevices, since the tuft is larger than many crevices. A brush having entirely soft bristles likewise fails to penetrate certain of these crevices, because all of the bristles tend to bend under pressure.
As FIGURE 4 illustrates diagrammatically, the soft bristles 13 penetrate the crevices between the teeth while the medium bristles 14 and the hard bristles 15 stabilize the soft bristles against bending away as pressure is applied to the body portion 10. The medium bristles 14 and the hard bristles 15 effectively clean the surfaces of the teeth while the soft bristles are penetrating the crevices. Inasmuch as there are substantially no bristles having a diameter departing from the various nominal values by more than .0005 inch, there can be no impediment to the desired interaction between th various classes of bristles.
Since the soft, medium, and hard bristles are combined in the tufts, localized cleaning effects are obtained for each tooth. Since only a few tufts can come into contact with a single tooth at one time, it has been found to be a particular advantage to combine the various bristles described above in a single tuft rather than to provide for each tuft only bristles of a single class.
Another advantage of a toothbrush constructed in accordance with the principles of the invention is that the action of cleaning the teeth is quicker since the crevices are cleaned at the same time the teeth are brushed, elim- Patented August 2, 1966 inating the need for subsequent treatment of th crevices. Moreover, while the soft bristles penetrate the crevices, the hard and medium bristles not only clean the surfaces of the teeth but massage the gums.
If desired, each of the bristles 13, 14, and 15 may be of different colors to give aesthetic appeal.
Of course, the total number of the bristles 13, 14, and 15 in each tuft 11 is not limited to the number shown in the drawings. Where an eight-bristle tuft is desired, however, it is preferred that one of the medium bristles 14 be eliminated rather than a. hard or a soft bristle. Also, in some instances, a tuft of only two classes of bristles may be usedfor example, the hard and the soft bristles. For optimum results, however, it is preferred that a tuft have all three classes of bristles.
Some of the desirable results inherent in this invention may be obtained by various modifications of the exact configurations shown. v The scope of the invention is therefore limited only by the terms'of the appended claims.
I claim: i
1. A brush comprising a body portion and a plurality of tufts attached to said body portion, each of said tufts comprising a first, a second, and a third group of bristles, each bristle of said first group of bristles having a diamto said body portion, each of said tufts comprising a relatively-small-diameter class of bristles and a relativelydiffering from each other by at least .003 inch, and
eter' of approximately .009 inch, each bristle of said second group of bristles having a diameter of approximately .012 inch, and each bristle of said third group of bristles having a diameter of approximately 0.13 inch, said third group of bristles being positioned in the center of each tuft, and said first and second groups of bristles being alternately arranged around said third group of bristles.
2. A toothbrush comprising a body portion for insertion into the mouth of a user and a plurality of tufts attached each of said tufts being free of bristles having a diameter within the range of (a) said relatively small value plus .0005 inch to (b) said relatively large value less .0005 inch. I
References Cited by the Examiner UNITED STATES PATENTS 2/1942 Millard et al 15167 FOREIGN PATENTS 1,134,245 11/1956 France.
705,725 3/1954 Great Britain.
1,134,245 11/1956 France.
707,725 3/1954 Great Britain.
CHARLES A. WILLMUTH, Primary Examiner.
PETER FELDMAN, Assistant Examiner.