BACKGROUND TO THE INVENTION Brushes, and more particularly broom heads, which are made from a synthetic material such as plastics, synthetic rubber and the like are well known. The bristles of the known brushes are generally parallel sided and are either round or rectangular in cross-section.

The bristles are uniformly flexible over their lengths.

Most of the known synthetic material broom heads are constructed from a number of separate mouldings which are in themselves expensive and labour intensive to assemble after moulding. For example, the relatively soft bristles are moulded to depend from or pass through a backing plate of one sort or another which is fixed to the broom head and in some cases the handle socket housing is made separate from the head and later fixed to it by welding or suitable adhesive.

With all synthetic material brooms known to the inventor of the broom of this invention, the predominant sweeping action of the brooms, particularly on carpets or carpet like surfaces, is backwardly towards the sweeper. The reason for this is that the broom head handle sockets and so the broom handles on the brooms in use are incline backwardly from the head towards the sweeper with the bristles being caused roughly to align with the pulling force imposed on them by the handle on the back stroke of the broom. On the forward broom sweeping stroke, however, the softly flexible bristles are caused to fold backwardly under the broom head with the forward and downward handle force then jamming the soft bristles against one another and downwardly onto the surface being brushed to result in high frictional resistance of the broom to forward motion and a negative sweeping result as loose material on the surface being swept and on the broom

bristles is now pressed into the surface as opposed to being swept from it.

SUMMARY OF THE INVENTION A sweeping brush according to the invention includes an integrally moulded elongated backing member and elongated sweeping blades which are substantially rectangular in cross-section and project outwardly from a common surface of the backing member with each of the sweeping blades having opposite sweeping faces which are transverse to the sweeping directions of the brush and which are tapered towards each other towards the free end of the blade. Conveniently, the edges of the blades on the sides of their sweeping faces also taper towards each other towards the free ends of the blades.

Preferably, at least a portion of the length of the sweeping faces of each sweeping blade from its free end towards the backing member is concave.

The sweeping blades may be spaced from each other in rows on the backing member with the blades in adjacent rows being staggered so that the blades in one row overlap the spaces between the blades in an adjacent row in the sweeping direction of the brush.

The sweeping blades in each row of blades may be progressively shorter from a central length of the row towards the longitudinal ends of the backing member.

The brush preferably includes a bracing member in the form of a flat plate which is embedded in and extends over a substantial portion of the length of the backing member and is made from a plastics material which is significantly less flexible than the remaining brush material.

In a preferred form of the invention the brush is a broom head and includes a broom handle engaging socket arrangement which is integral with the backing member material and projects outwardly from a surface of the backing member opposite the surface from which the sweeping blades project. With this version of the invention the bracing plate carries an integral outwardly projecting reinforcing sleeve which is coaxially bonded to the material of the broom handle socket.

The material from which the backing member and sweeping blades may be made is a mixture of 80% ethylene vinyl acetate resin and 20% of low density polyethylene with the mixture having a shore hardness on the A scale of between 65 and 75.

The material from which the bracing member is made is polypropylene having a shore hardness on the D scale of between 60 and 70.

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention is now described by way of example only with reference to the drawings in which : FIGURE 1 is a front elevation of a broom head according to the invention, FIGURE 2 is a plan view of the Figure 1 broom head, FIGURE 3 is an underplan of the broom head of Figures 1 and 2, FIGURES 4 and 5 are enlarged side elevations of the broom head shown sectioned on the lines 4-4 and 5-5 in Figure 1 respectively, FIGURE 6 is an enlarged front elevation of a sweeper blade of the broom, FIGURE 7 is a side elevation of the Figure 6 blade, FIGURE 8 is an enlarged plan view of the blade of Figures 6 and 7 as seen from its upper end, and FIGURE 9 is a fragmentary diagrammatic side elevation of two of the sweeping blades of the brush of the invention, in use, illustrating the flex of the bristles.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The broom head 10 of the invention is shown in Figures 1 to 5 to include a backing member 12, sweeping blades 14, a handle socket housing 16, a squeegee blade 18 and a bracing member 20.

The backing member, blades 14 and the squeegee 18 are integrally moulded from a plastic material consisting of 80% ethylene vinyl acetate resin and 20% of a low density polyethylene having a shore hardness on the A scale of between 65 and 75. The bracing member 20 is moulded from a substantially more rigid material such as polypropylene having a shore hardness on the D scale of between 60 and 70 which, during the moulding process of the remainder of the broom head over it, is thermally bonded in the mould to the head material.

The bracing member 20 consists of a rectangular plate 22 which is a little smaller in dimension than the broom head in plan, an incline reinforcing socket 24 for the socket housing 16 and two triangular bracing gussets 26, which extend from the wall of the socket 24 onto the plate 22, as shown in Figure 1. The material of the bracing plate 22, as mentioned above, is thermally bonded to the head material as the head material is moulded over it. The plate 22 may additionally, however, include a number of suitably spaced material keying apertures 28, as shown in Figure 4, further to ensure the integrity of the head materials during even the most robust use of the broom head.

The sweeping blades 14 of the broom head are shaped as shown in Figures 6 to 8. The relative dimensions of the various portions of the blades are shown in millimetres in these drawings but it is to be understood that these dimensions are in no way limiting to the invention and are provided merely to illustrate the currently optimal dimensional proportionality of the blades. As is seen in Figure 8, the sweeping faces of the blades are each concave to provide a scooping action while sweeping which tends to throw particulate matter being swept in the sweeping direction with very little sideways component which is not the case with bristles which are round or even purely rectangular in cross-section. The cross-sectional shape of the blades additionally enhances the

predominant tip-action flexibility of the blades during sweeping as is shown in Figure 9.

Although the concave surfaces of the blades shown in the drawings are V-shaped the surfaces could equally well be smoothly curved.

As will be seen from Figures 3,4 and 5, this embodiment of the broom of the invention carries six or seven rows of sweeping blades 14 with alternate rows being staggered so that the space between the blades of each row is covered by the blades in an adjacent row in the sweeping direction of the broom to ensure that particulate dirt does not traverse the broom head during sweeping.

As will be noticed from Figure 1, the sweeping blades 14 are made progressively shorter from the central zone of each row of blades towards the longitudinal ends of the backing member. The purpose of this arrangement is that when only light sweeping is required from a broom including the boom head 10, such as would generally be the case over a domestic carpet, the frictional sweeping resistance of the outer sweeping blades of each row of blades is eliminated or at least minimised to lighten the required sweeping pressure on the broom handle.

It has been established during extensive trials with the broom of the invention on various surfaces that six rows of sweeping blades 14 are adequate for conventional sweeping and are significantly less than the number of bristle rows to be found on conventional synthetic material brooms. This results in the broom head of the invention being lighter in weight and so relatively cheaper than conventional synthetic broom heads.

The most important features of the broom of the invention are the shape of the bristle blades and the hardness of the material from which they are made. As mentioned above, conventional moulded synthetic broom bristles are uniformly or very nearly so, flexible over their lengths. The blades 14 of the broom head of the invention on the other hand are, principally because of their two direction tapered shape and the material from which they are made, progressively more flexible towards their free ends to result in a predominantly tip flex action as illustrated in Figure 9. As is shown in Figure 9, even with moderately high sweeping pressure, in the direction of the arrow in the drawing, the

bristles of the broom of the invention do not fold up under the head 12 and jam against one another and as a result the forward sweeping efficiency of the broom is much the same as its rearward efficiency making the broom of the invention a far more useful sweeping implement than the known almost single direction sweeping synthetic brooms.