US2258361A - Paintbrush - Google Patents

Description

l |=|G."4. Y Heus.l Haz L. s. HEwEs PAINTBRUSH Filed June `2&3, 193s- 2 sheets-sheet 2 lNvENToR l LAWMWCESHEWES ATTORNEY In Fig. 5 the ferrule 2 is shown placed in an intermediate position on the formed body of bristles I', this being a step in the fabrication of the 'brush enabling the butt ends of the bristles to be treated with a binding compound, preferably one having a rubber base, in any suitable manner, such as by dipping. The binder is in this way permitted to fill the spaces between the butts to a predetermined distance and serves to nrmly cement into a unitary body or knot, one end of the bristles which are to form the brush. The portion of the bristle bunch treated bristle-body, as a Whole', firmly in the ferrule knots having square cut butt ends.

and retaining the individual bristles firmly in the knot, as will be more fully explained hereinafter. For these purposes the wing yportions peaned or otherwise set in a iiianner to make thebristle-body and its surrounding ferrule, a

` mechanically and firmly connected unit.

use of the brush to be borne by a stronger body,A

i. e., a mixture of bristles and'czement,v than the cement or binding ller alone.l It has been found unsatisfactory to depend on anchorage throughv the filler al'one due to its structural need not extend into the ferrule to a `greater distance than is customary with respect to bristle In general it may be said. that the wing portions need not .extend more. than about 1/2 inch into the ferrule.

. attached by means of the ferrule.

In larger sizedbrushes they may need to extend into the ferrule slightly more than half an inch while in smaller brushes they need not extend into theferrule even as much as this. Viewed from another angle it may be said that the winged end of the knot should extend into the ferrule far enough to locate the bottom of the valley` 'i say between 1A; and 1A of an inch or even less above a plane extending across the lower e'dges of the ferrule. A desired quantity of the same or other suitable bonding material is thenplaced in the ferrule 2, Fig. 6, to form a. portion I0 above the bristle knot, and the unit is subjected to processing which finally solidifles the bonding material and causes the 'parts 9 -and i0 to unite and form a unitary base adhering to the ferrule and having the bristle ends firmly and xedly embedded therein, thus forming a sub-assembly to which any suitable type of handle may be The processing of the binding material, when a rubber compound is used', is commonlykno'wn as vulcanizing, but it will be understood that other adhesive, binding substances may be employed, if desired, and subjected to appropriate processing conditions.

As is well known, certain types and sizes of brushes are subjected to severe strains in use,

'and are further subjected to various conditions and treatments which tend to loosen the bristlebody from the ferrule and to expand this body with a consequent distortion of the encasing ferrule. To reinforce the brush and strengthen it so as toprevent such deformation, it is desirable to further anchor the bristle body i in and to the ferrule 2, and to so clamp the opposed sides of the latter as to resist the distorting forces. For this purpose holes may be made in the ferrule and the adjacent bristle body and headed nails or rivets I-I ofl suitable length may be driven in the holes and through the bristle unit. The exposedl ends of these nails or rivets opposed to the heads may then be clinched,

weakness. Now in accordance with the present invention the winged structure, which is a combination of bristles and bonding agent, serves very effectively to bear the strains imparted-in the use of the brush, particularly in view of the fact that the wings are reinforced o r backed by the binding filler provided in the valley 1. The resistance to strains is equally as good as if the bristle butt were sheared straight across and extended into the ferrule the same amount as the wings of the improved construction. Yet there is a substantial saving in the bristles because the average amount to which they extend into the ferrule is considerably reduced. While, with this arrangement, the bristles which terminate adjacent the bottom of the trough 1 extend into the ferrule only a slight distance, it'has been found that they are firmly held in the bristle-body by virtue of the action of the cementing agent and the clamping effect of the outer bristles forming the wings. On the other hand, if the innermostv bristles do not extend into the ferrule a slight distance they Willhave a tendency to tear loose from the knot in the course of severe usage.

When nails or rivets are employed` to reinforce the construction, as explained above, these may be passed through the cemented'end of the bristle body just below the bottom of the valley 1, as shown in Figure 7, which will insure maximum strength and avoid any danger of having the nails form an opening or split to the end of the bristle body. However, substantially equal strength can be attained by passing the nails merely through the wings 8 above the bottom of the trough or valley fl so that a part of the nails will also be anchored in the downward i extension of theA binding compound I0, as shown in Figs. 3 and 4. This feature -of the improved operative end I3a, instead of the chisel end and' brush brings about a substantial saving in the length of the bristles. Inasmuch as the nails Il will ordinarily be driven through the ferrule at a given distance, less than a quarter of an inch in the average brush, from the lower edge cf the ferrule, preferably adjacent a lower bead or between a pair of beads extending around the nferrule near its lower edge, that portion of the bristle body that is held Within the ferrule may be reduced to a minimum by adopting this feature of the present invention. Thus a brush of given size that has its bristles projecting a given` length from the lower edge of the ferrule, is produced with minimum bristle length.

As a special modification the inventionmay be applied to brushesv having a substantially dat particularly where such brushes have the outer faces 'or' sides composed of bristles of a kind the structure might be such as to provide a plurality of valleys with one or more dividing lay-` ers of bristles. Onesuch dividing layer is illustrated in the brush ofFig. 9 in which I2, I2 are the outer layers, I a dividing layer and I3', I3' the valleys formed between these layers. As in the illustrated forms hereinbefore described this particular construction also permits the use of a minimum length of bristle in portions of l the brush body as 'a result of the wing-like extensions of the outer layers and possible inter. mediate layer or layers. It will be understood that nails maybe inserted as described and as shownrat II in Fig. 9.

Fig. 10 illustrates the application of features of the invention to another type of brush in which an inserted plug I forms a part of the butt endv rf the bristle body. In other respects this form zf the brush is shown as similar to that illustrated in Figure A3 but it will be understood that it might follow the construction of any of the modifications such an inserted plutghis used it brings about-an inward tapering o f e bristle body toward the lower end which may be supplemented by the chisel-like formation of the group of bristles themselves.

While certain illustrative forms of brushes embodying the principles and features of the present invention have been described in considerable detail it will be understood that numerous other variations and modifications may be made and that the features may be applied to various types of ferrules, with or without nails, rivets or other clamping devices, without departing from the scope of the invention. 1t will be understood that features disclosed in connection with one embodiment may be utilized, if desired, in connection with one or another of the other embodiments. Inigeneral, it may be said that the invention provides a brush having agiven effective bristle length, i. .e., from the bottom of the` ferrule to the tips of the bristles, with a minimum actual bristle length and without m'aterially weakeningv the construction of the brush as awhole. i what is claimed ii:

1. A brush comprising a bristle body, a ferrule surrounding a portion of said bristle body. said bristle body being formed to provide a depression in its upper end denned by upwardly extendingl wing portions and to provide a complementary chisel-like formation at its lower end, cementing means permeating substantially the entire upper end of the bristle body within the ferrule for bonding together the bristles 'in and adjacent the wing portions, and additional cementing means bonded to form an integral unit with said first-mentioned cementing means and hereinbefore described. When filling said depression, the said upper end of the bristle body extending into the ferrule a sui'licient distance -to retain nrmly in the bristle body the innermost bristles adjacent the bottom of said depression but only to auch extent as to place the bottom of said depression not more than about three-sixteenths of an inch above the lower edge of the ferrule, the construction being such as to eilect a saving in the length of the bristles employed while providing a strength substantially equal to that of a brush in which the bristle knot is square-cut at its upper end and is inserted in the ferrule to the same extent as said wing portions.

' 2. A brush comprising a bristle body, a ferrule surrounding a portion of said bristle body, said bristle body being formed to provide a depression in its upper end defined by upwardly extending wing portions and to provide a comple-y mentary chisel-like formation at its lower end, cementing means permeating substantially the entire upper end of the `bristle body within the ferrule for bonding together the bristles in and adjacentV the wing portions, and additional cementingmeans bonded to form an integral unit with said first-mentioned cementing means and lling said depression, said wing portions extendirig into the ferrule a distance no greater-.than the usual extent of a bristle knot having its upper end square-cut, the construction being such as to effect a saving in the length of the bristles employed while providing a strength substan-l tially equal to that of a brush in which the bristle knot is square-cut at its upper end and is inserted in the ferrule to the same extent as said wing portions.

3. A brush comprising. a bristle body, a ferrule surrounding a portion of said bristle body, said bristle body beingformed to provide a depression in its upper end defined by upwardly extending wing portions and to provide a complementary chisel-like formation at its lower end,

cementing means permeating substantially the pression to form an integral unit with the bristle body, said upper end extending into the ferrule only a suicient distance to retain firmly in the bristle body the innermost bristles adjacent the bottom of said depression, and fastening means` extending through said ferrule, said wing por# tions, and the cementing means within said depression, the construction being such as to effect a saving in the length of the bristles employed while providing a strength substantially equa1 to that of a brush in which the bristle knot is square-cut at its upper end and is inserted in the ferrule to the same extent as said wing portions. v v

4. A method of making a brush involving 'a saving in bristle length without sacrincing any strength which comprises forming a group of bristles of substantially the same length into a body having a chisel-like formation at one end and a complementary depression at its other end, applying a cementing substance to said other end of said body and permeating the same with said substance adjacent said depression, permitting said substance to only partially age and solidify, placing said end with the` partially solidified cementing substance in its nnally desired position in a ferrule, adding more ofthe same cementing substance to fill said depression, and applying a handle to said ferrule.

' LAWRENCE S. HEWES.

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