GB2052963A - Brush tuft element - Google Patents

Abstract

A method of fabricating a brush tuft or tuft assembly comprising the steps of arranging together a plurality of individual strands (15) of material with suitable individual shape, size and abrasive and wearing properties into an assembly (13) of the desired overall cross-sectional shape, size and to the desired length, fitting a hollow metal sleeve (19) over the strand assembly (13) and crimping tho sleeve (19) to secure firmly together the individual strands (15) within the crimped sleeve (14), folding (22) the sleeve (19) over at the crimp (21) to form a tuft assembly with exposed free strand ends (15) at one end and an enlarged head defined by the sleeve (19) at the opposite end. <IMAGE>

Description

SPECIFICATION Brush tuft element This invention relates to brushes and is particularly concerned with a brush tuft or tuft assembly incorporating a plurality of individ-ual strands and which is adapted for mounting in a support with a collection of other tufts to form a multi-tuft brush head.

The invention is particularly, but not exclusively, concerned with heavy duty brushes in which the individual tuft strands are fabricated of heavy duty material with high abrasive and hard wearing properties, such as metal wire.

By way of example, an important application of such heavy duty brushes is in mobile, vehicle-mounted street cleansing equipment incorporating heavy duty gutter brushes. In practice, even with heavy duty brushes incorporating heavy duty section wire strands, there is an appreciable wear rate and brushes or brush tufts must frequently be replaced.

Generally, the fabrication of heavy duty brushes does not lend itself to mechanised production processes, such as high output brush making machinery, and the fabrication has to be carried out largely by hand. This is laborious and time consuming and increases production costs, particularly as compared with the production of conventional brushes with lighter duty, finer gauge strands on conventional brush making machinery.

A particular problem is encountered in trying to adapt conventional brush making machinery for heavier gauge strands, whether of round, oval, square or rectangular section.

Generally such strands are assembled by hand into a tuft and'laced in position by lighter gauge soft wire and then mounted on a support or backing plate.

According to the invention, a method of fabricating a brush tuft or tuft assembly comprises the steps of arranging together a plurality of strands of material with suitable abrasive and wearing properties and individual strand size into the desired overall cross-sectional shape, size and to the desired length, fitting a hollow metal sleeve over the strand assembly and crimping the sleeve to secure firmly together the individual strands within the crimped sleeve, folding the sleeve over at the crimp to form a tuft assembly with exposed free strands at one end and an enlarged head defined by the sleeve at the opposite end.

The tuft thus fabricated may then be inserted in a support or backing member, for example by passing the tuft through a correspondingly shaped aperture in the backing member and locating the tuft securely therein by frictional engagement of the crimped end in the aperture. A backing or support member may be fixed against the head of the crimped end one received in the aperture in this manner to inhibit withdrawal from the aperture under load.

Optionally, the aperture and/or the crimped head of the tuft may be orientated to achieve a desired orientation of the tuft in the support member.

There now follows a description of a particular embodiment of the invention, by way of example only, with reference to the accompanying diagrammatic drawings, in which: Figures la to le inclusive show successive stages in a fabrication method for a brush tuft according to the invention; Figure If shows a modification of the brush tuft shown in Fig. le; Figure 2 shows a perspective view of the brush tuft shown in Fig. 1 e; and Figure 3 shows a sectional view of the manner of assembly of brush tufts according to Fig. 2 in a support and backing member forming a brush head.

Referring to the drawings, a brush tuft 1 4 according to the invention is fabricated by assembling generally equal length strands of desired properties, in particular cross-sectional shape and size and material hardness to achieve desired brush abrasive and wearing properties. The strands 1 5 may be generally similar or a mixture of different types (as indicated on opposite sides of the break line in Fig. la) and are aligned at their opposite ends 1 6 and 1 7 in an assembly 1 3 of corresponding cross-sectional shape and size to that of the desired tuft and typically being of circular section.A hollow sleeve 1 9 of internal section corresponding to that of the dsired tuft cross-sectional shape and size is slid over the assembly 1 3 to a point 1 8 generally midway between its opposite ends 16 and 1 7. The sleeve 1 9 is then locally deformed by the application of lateral pressure, as indicated at 20, to form a local restriction or crimp 21 by which the individual strands 1 5 are firmly secured together. - The crimped sleeve 1 9 is then folded over about the crimp 21, as indicated by dashed lines in Fig. 1d, until the sleeve 1 9 is formed into generally a U-shape and the opposite ends 1 6 and 1 7 of the strands 1 5 of the assembly 1 3 are brought adjacent and into line as shown in Fig. le.

The resulting tuft 1 4 has a collection of aligned free strand ends at one end and a reinforced enlarged head 23 at the opposite end for mounting of the tuft 1 4. During the folding operation of the sleeve 1 9 to form the head 23 of the tuft 14, the latter may be canted to give any desired orientation of the head 23 relative to the strands 15, for example the acute orientation as shown in Fig. 1 f, in order that the tuft 1 4 may be orientated in the desired direction when mounted in a brush head, as described later with reference to Fig. 3.

Fig. 2 shows a perspective view of the tuft in which the head 23 has a larger cross sectional diameter D1 than that of the sleeved strand assembly 13, as indicated by D2.

Fig. 3 shows how the tuft head 23 configuration may be used to mount the individual tufts 14 in a support member 25, with tuftreceiving apertures 26 of corresponding crosssectional shape and size to the tuft crosssection D2 so that the individual tufts 14 are located laterally and are restrained from moving through in one longitudinal direction by virtue of the enlarged head 23. The latter is engaged by a backing member 30 fitted to the support member 25 and thus the individual tufts 14 are secured firmly in position.As indicated in dashed lines at 28 in Fig. 3, the apertures for the individual tufts 14 may be arranged at any desired angle to the general plane of the support member 25, in particular to orientate the tufts 1 4 at an acute angle a as indicated and to form a flared brush head configuration from the combination of individual tufts 14.

The brush head assembly defined by the individual tufts or tuft assemblies 1 4 mounted in a support member 25 may vary in shape and size according to the desired purpose. For example a heavy duty gutter brush for a vehicle-mounted, mobile street cleansing machine as previously mentioned would have a generally circular configuration with the outer tuft or tuft assemblies 14 progressively flared outwards to allow the brush head to approach the gutter at an angle to reach into the corner of the gutter.

CLAIMS (6 July 1979) 1. A method of fabricating a brush tuft or tuft assembly comprising the steps of arranging together a plurality of strands of material with suitable abrasive and wearing properties and individual strand size into the desired overall cross-sectional shape, size and to the desired length, fitting a hollow metal sleeve over the strand assembly and crimping the sleeve to secure firmly together the individual stands within the crimped sleeve, folding the sleeve over at the crimp to form a tuft assembly with exposed free strands at one end and an enlarged head defined by the sleeve at the opposite end.

2. A method according to Claim 1 in which the head is folded to lie inclined with respect to the strands in order that the strands may be presented at a desired orientation when the head is fitted into a support member.

3. A method of fabricating a brush tuft or tuft assembly, substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

4. A brush tuft or tuft assembly produced by the method according to any of the preced

Claims (4)

ing claims. 5. A brush head incorporating a plurality of brush tufts or tuft assemblies according to Claim 4, fitted into correspondingly shaped and sized apertures in a support member, the apertures being arranged to present the individual tufts or tuft assemblies at the desired spacing and orientation. 6. A brush tuft or tuft assembly substantially as hereinbefore described with reference to, and as shown in the accompanying drawings. 7. A brush head substantially as hereinbefore described with reference to, and as shown in, Fig. 3 of the accompanying drawings. CLAIMS (16 September 1980)

1. A method of fabricating a brush tuft or tuft assembly comprising the steps of arranging together a plurality of strands of material with suitable abrasive and wearing properties and individual strand size into the desired overall cross-sectionai shape, size and to the desired length, fitting a hollow metal sleeve over the strand assembly and crimping the sleeve to secure firmly together the individual strands within the crimped sleeve, folding the sleeve over at the crimp to form a tuft assembly with exposed free strands at one end and an enlarged head defined by the sleeve at the opposite end and by which the individual tuft assembly may be restrained from withdrawal from a mounting aperture.

2. A method according to Claim 1 in which the head is folded to lie inclined with respect to the strands in order that the strands may be presented at a desired orientation when the head is fitted into a support member.

3. A method of fabricating a brush tuft or tuft assembly, substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

4. A brush tuft or tuft assembly produced by the method according to any of the preceding claims.