GB2408926A

GB2408926A - Brush attachment

Info

Publication number: GB2408926A
Application number: GB0328704A
Authority: GB
Inventors: Nicholas Andrew Brown
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-12-11
Filing date: 2003-12-11
Publication date: 2005-06-15
Anticipated expiration: 2023-12-11
Also published as: GB2408926B; GB0328704D0

Abstract

A brush attachment for a mechanical sweeping machine comprises a base plate 110 defining an upper and lower base surface 112; 114, a securing plate 150 defining an upper and lower securing surface and brush filaments 140. The securing plate is reversibly receivable by the upper base surface of the base plate. Both the base plate and the securing plate are provided with a plurality of channels 120a; 152a; 152b for threaded receipt of the brush filaments extending from their upper surfaces to their lower surfaces. Upon threaded receipt of the brush filaments by the base plate and the securing plate, the brush filaments are secured thereby such that filament ends 142 thereof splay out from the lower base surface of the base plate.

Description

Brush attachment The present invention relates to a cleaning tool. In

particular, the present invention relates to a rotating sweeping brush for use with a mechanical sweeping machine such as that used for the cleaning of road surfaces.

Mechanical sweeping machines are used widely by government authorities, environmental agencies and other organizations that have the responsibility for cleaning large public surfaces or transport highways. The rotating sweeping brush used therewith typically comprises a plate (e. g. ring-shaped) into which flexible sweeping filaments, commonly referred to as bristles, are permanently threaded. Typically, the plate of the rotating sweeping brush comprises a plurality of thread-receiving channels provided thereto, wherein the upper entry holes to each channel are arranged radially, but the channels splay out at an angle to the plane defined by the plate. This arrangement may be better understood by referring to Figure 1, which shows a prior art sweeping brush and to Figures 2 and 3a, which respectively show a top and cross- sectional view (about D-D) of an unthreaded plate of the prior art sweeping brush of Figure 1.

In more detail, Figures 1, 2 and 3a shows circular plate 10, to which plural thread- receiving channels 20a-c are provided concentrically in regular radial arrangement about the centre 30 of the plate 10. The circular plate 10 is also provided with fixing holes 11 for fixing to a rotary sweeping machine. Each channel 20a-c may be seen to splay outwards from the centre 30 such that each entry hole 22a-c thereto is radially closer to the central axis 30 than is each exit hole 24a-c. The motivation for adopting such a splayed out channel arrangement becomes apparent when reference is made to Figure 1 and to Figure 3b, which shows a cross-sectional view (again about D-D) of the plate of Figures 2 and 3a, now threaded. Bristle filaments 40a-c are received in threaded fashion at each pair of channels 20a-c such that the bristle ends thereof splay out to form a suitable overall sweeping brush form.

The Applicant has now realized that the conventional sweeping brush described above has a number of disadvantages.

A first set of disadvantages arises because the brush filaments are designed for permanently threading to the plate. Once the bristle ends have worn down, the entire plate and the remaining sweeping elements are generally disposed of as they cannot easily be separated or re-used. Moreover, as the plate used to support the brush filaments and form the brush must be disposable it is economically necessary to manufacture it from an inexpensive material. This often results in a plate that is not durable or fully waterproof and can therefore promote the premature failure of the brush during arduous use.

A further set of disadvantages arises because of the splayed out configuration of the channels provided to the plate of the conventional sweeping brush. Such a configuration is very difficult to manufacture from by a moulding process because a suitable straightforward moulding (e. g. injection-moulding) tool cannot be readily applied to the plate to form radially arranged, splayed out channels. The problem arises because such a tool would need to comprise plural pins radially arranged in splayed out fashion to mirror the required channel configuration. Once such pins are inserted en masse into the plate to create the channels the splayed channel geometry form makes it very difficult to again withdraw the pins en masse. Whilst this problem could be addressed by having a tool with individually insertable and retractable pins, such solution would be expensive and require not only a complex tool but also complex systems to control individual pin movements.

The difficulties in applying a moulding process to the conventional sweeping brush arrangement have meant that the conventional manufacturing process instead involves individually drilling channels in the desired radial, splayed out arrangement into a bare plate. This individual holedrilling process is time-consuming and labour-intensive.

The splayed out configuration of the channels also makes it difficult and time-consuming to remove used bristles for recycling thereof. In essence, each bristle set must be removed individually from its threaded location by a laborious process that is complex to automate.

To address the above-described problems the Applicant has now devised a rotating sweeping brush attachment that is readily susceptible to manufacture by a moulding process and that enables recycling of used brush filaments, whilst still providing for the desired splayed out presentation of brush filament ends to provide the overall brush.

In another aspect, the rotating sweeping brush attachment herein provided comprises a base plate provided with channels arranged radially for receipt of suitable brush filaments and a securing plate reversibly applicable to the plate to reversibly secure the brush filaments in the desired brush configuration, wherein the securing plate also comprises plural channels for threaded receipt of brush filaments. In combination, the bristles are wedged within the base plate and securing plate such that the bristles are secured and the filament ends thereof splay out from the lower surface of the base plate. The bristles are readily withdrawn from the base plate for recycling by withdrawing the securing plate (and bristles threaded thereto) from the base plate.

In another aspect, the rotating sweeping brush attachment herein provided comprises a plate provided with generally tapering channels (e.g. 'wedgeshaped' in cross-sectional profile) arranged radially for receipt of suitable brush filaments and a securing means reversibly applicable to the plate to reversibly secure the brush filaments in the desired brush configuration. Such a plate is readily susceptible to manufacture by a moulding process.

According to one aspect of the present invention there is provided a brush attachment for a mechanical sweeping machine comprising a base plate, said base plate defining an upper and lower base surface; provided to the base plate and extending from said upper to lower base surface, plural channels for threaded receipt of brush filaments; reversibly receivable by the upper base surface of the base plate, a securing plate, said securing plate defining an upper and lower securing surface; and provided to the securing plate and extending from said upper to lower securing surface, plural channels for threaded receipt of said brush filaments, wherein upon threaded receipt of the brush filaments by the base plate and the securing plate the brush filaments are secured thereby such that filament ends thereof splay out from the lower base surface of the base plate.

The brush attachment herein is suitable for use with a mechanical sweeping machine, for example of the type used for sweeping large public spaces and / or roads.

The brush attachment comprises a base plate. The base plate is generally of substantially planar form, and typically has a generally circular profile. The base plate is s suitably provided with for means for attaching it to drive means of a mechanical sweeping machine.

The base plate defines an upper and lower surface. In use, the upper surface of the plate will face towards the drive means of the mechanical sweeping machine (generally upwards) and the lower surface will face towards the surface to be brushed (generally downwards).

The base plate is provided with plural channels for threaded receipt of brush filaments.

The channels extend from the upper to lower surface of the plate (i.e. generally through the plate in lateral fashion). On threaded receipt of the brush filaments, the profile of the respective channels is such that the filament ends of the brush filaments splay out from the lower surface of the base plate. That is to say the filament ends of the brush filaments project from the channels at the lower plate surface such that they are splayed out to form a brush-like configuration extending below and away from the lower surface of the plate.

Securing means are used to secure said threaded brush filaments within said plural channels. The securing means is reversibly receivable by the upper surface of the base plate.

The securing means is in the form of a securing plate (e.g. ring-shaped plate) defining an upper and lower securing surface. The securing plate is provided with plural channels for threaded receipt of said brush filaments, wherein the plural channels extend from the upper to lower securing surface.

Upon threaded receipt of the brush filaments by the base plate and the securing plate the brush filaments are secured thereby such that filament ends thereof splay out from the lower base surface of the base plate. It will therefore be appreciated that the brush filaments are secured in place by the gripping / wedging action (of the channels) of the base plate and securing plate acting in combination (i.e. jointly).

Orientation of the brush filaments to the desired splayed-out configuration is suitably achieved through appropriate shaping of the geometry (e.g. by tapering as described hereinafter) of the plural channels of the base plate.

Suitably, the plural channels of both the base plate and securing plate are radially arranged (e.g. in concentric circle arrangement) but the radius defined by the plural channels of the base plate is greater than that defined by the (relevant, matching set of) plural channels of the securing plate. This arrangement means that when the securing plate is received by the base plate the relevant channels (e.g. sets thereof) are in off-set registration, which assists wedging of the relevant brush filaments.

Suitably, the securing plate of generally similar form (e.g. shape, size) to that of the base plate and receivable in mating fashion by the base plate. Suitably, the securing plate is provided with fixing means for reversibly fixing it to the base plate.

In one aspect, the securing plate is a ring-shaped plate member receivable within a ring-shaped recess provided to the upper base surface of the base plate.

The invention provides the potential advantage that only the sweeping elements, that is, the brush filaments, need to be transported from the manufacturer to the user. The base plate and the securing means may be reused many times and can therefore be manufactured in a manner that will be suitable for more arduous duty.

Suitably, each of the plural channels provided to the base plate has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.

Preferably, the tapering profile is such that part of each tapering channel is generally perpendicular to the plane defined by the plate and part of each tapering channel defines an acute angle to the plane defined by the plate. It will be appreciated that the part of each tapering channel which defines an acute angle is arranged such that the channel profile thereby defined acts such as to guide the filament ends of threaded brush filaments to splay out from the lower surface of the base plate.

A preferred tapering profile is generally 'wedge-shaped' when viewed in cross-section (wherein a suitable cross-section is one perpendicular to the plane defined by the plate and bisecting a tapering channel). The part of the 'wedge' that is substantially perpendicular to the plane defined by the plate is located more distant from the centre of the plate than is that part of the 'wedge' that defines an acute angle to the plane defined by the plate.

Suitably, each of the plural channels provided to the securing plate has a non-tapered profile. That is to say, the cross-sectional area of an entrance thereto at the upper surface of the securing plate is equal to that of an exit thereto at the lower surface of the securing plate.

According to another aspect of the present invention there is provided a brush attachment for a mechanical sweeping machine comprising a base plate, said base plate defining an upper and lower surface; provided to the base plate and extending from said upper to lower surface, plural channels for threaded receipt of brush filaments such that filament ends of said brush filaments splay out from the lower surface of the base plate; and reversibly receivable by the upper surface of the base plate, securing means to secure said threaded brush filaments within said plural channels, wherein each of the plural channels has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.

According to another aspect of the present invention there is provided a base plate for use with a brush attachment for a mechanical sweeping machine as described hereinbefore, said base plate defining an upper and lower surface; and provided to the base plate and extending from said upper to lower surface, plural channels for threaded receipt of brush filaments such that filament ends of said brush filaments splay out from the lower surface of the base plate, wherein each of the plural channels has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.

There is also provided a moulding (e.g. injection-moulding) process for making the base plate by use of a suitable mould.

According to a further aspect of the present invention there is provided a threaded brush attachment for a mechanical sweeping machine comprising a brush attachment as described herein and received by the plural channels, brush filaments arranged such that filament ends of said brush filaments splay out from the lower surface of the base plate.

Suitable brush filaments are formed from a plastic polymer (e.g. polypropylene) or a metal (e.g. steel).

According to a further aspect of the present invention there is provided a mechanical sweeping machine comprising a drive motor; and drivable in sweeping fashion thereby, a brush attachment or threaded brush attachment as described herein.

Suitably, the brush attachment or threaded brush attachment additionally comprises fixing means (e.g. a fixing plate) to fix the brush attachment to the drive motor of the mechanical sweeping machine. Preferably, the fixing plate and brush attachment are secured through a quick-release fixing mechanism.

According to one aspect of the present invention there is provided a kit of parts for a brush attachment for a mechanical sweeping machine comprising (a) a base plate, said base plate defining an upper and lower base surface, wherein said base plate is provided with plural channels for threaded receipt of brush filaments, said plural channels extending from said upper to lower base surface; (b) reversibly receivable by the upper base surface of the base plate, a securing plate, said securing plate defining an upper and lower securing surface, wherein said securing plate is provided with plural channels for threaded receipt of brush filaments, said plural channels extending from said upper to lower securing surface; (c) brush filaments for threaded receipt by the plural channels of the base plate and securing plate; and wherein upon threaded receipt of the brush filaments by the base plate and the securing plate the brush filaments are secured thereby such that filament ends thereof splay out from the lower base surface of the base plate.

In a further aspect of the present invention there is provided a kit of parts for a brush attachment for a mechanical sweeping machine comprising (a) a base plate, said base plate defining an upper and lower surface, wherein the base plate is provided with plural channels extending from said upper to lower surface, said plural channels for threaded receipt of brush filaments such that filament ends of said brush filaments splay out from the lower surface of the base plate; (b) brush filaments for threaded receipt by the plural channels; and (c) reversibly receivable by the upper surface of the base plate, securing means to secure said threaded brush filaments within said plural channels, wherein each of the plural channels has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.

The invention will now be described further with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a conventional (i.e. prior art) sweeping brush attachment; Figure 2 shows a plan view from above of the conventional (i.e. prior art) sweeping brush attachment of Figure 1 absent its bristles; Figure 3a shows a crosssectional view of the conventional sweeping brush attachment of Figure 2, the cross-section taken along line D-D of Figure 2; Figure 3b shows a cross-sectional view of the conventional sweeping brush attachment of Figure 2 as threaded with bristles, the cross-section again taken along line D-D of Figure 2; Figure 4 shows a plan view from above of a first sweeping brush attachment herein; Figure 5 shows a cross-sectional view of the sweeping brush attachment of Figure 4, the cross-section taken along line X2-X2 of Figure 4; Figures 6a and 6b show sequential steps in a suitable moulding process herein as depicted in cross-sectional view.; Figure 7a shows a cross-sectional view of a second sweeping brush attachment herein; and Figure 7b shows in cross-sectional view the second sweeping brush attachment of Figure 7a as threaded with bristles.

In more detail, Figures 4 and 5 show a first embodiment of the sweeping brush attachment herein comprising circular base plate 110 defining upper 112 and lower 114 planar surfaces. Plural thread-receiving channels 120a, 120b are provided to the base plate 110 in pair-wise in regular radial arrangement about the centre 130 of the plate 110. Bristle filaments 140 are received in threaded fashion at each pair of channels 120a, 120b such that the bristle ends thereof 142 splay out from the lower surface 114 of the base plate 110 to form a suitable overall sweeping brush form.

Each channel 120a may be seen to have a particular tapered (or 'wedgeshaped') form wherein each entry hole 122 provided at the upper surface 112 of the base plate 110 has a larger diameter, and hence crosssectional area than its corresponding exit hole 24 provided at the lower surface 114 of the base plate 110. In more detail, each channel 120a may be seen to have a first part (i.e. a part of the wall of the channel) 126 that is essentially perpendicular to the plane defined by the base plate 110 and a second part (i.e. another part of the wall of the channel) 128 that defines an acute angle to the plane defined by the base plate 110. It may be seen that the second, acute-angled wall 128 of the channel acts such as to guide the received threaded brush filament 140 such that the desired splayed-out brush ends 142 configuration is adopted.

The upper surface 112 of the base plate 110 is further provided with securing means in the form of a securing plate 150 having apertures 152 provided thereto, each arranged for registration with the entry 122 to an adjoining pair of channels 120a, 120b. The securing plate150 is further provided with a screw fixing means154 for reversibly screw fixing it to the base plate 110. It may be seen that when the securing plate 150 is sofixed to the base plate 110 the received brush filaments 140 in the channels 120a, 120b of the base plate 110 are secured in place.

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In use, the securing plate 150 is tightly screwed down to the base plate 110 to secure the brush filaments 140 in place. When however, the ends 142 of the brush filaments become worn down, they may be replaced by unscrewing the screw fixing means 154 to enable the securing plate 150 to be removed from the base plate. The worn brush filaments 140 are then removed and the channels rethreaded with fresh brush filaments 140.

It is an advantage of the present invention that the base plate 110 of the brush attachment is readily manufacturable by a moulding process. Figures 6a and 6b show in schematic form sequential steps in a suitable moulding process.

In Figure 6a, first trough form mould 160 defines the outline of the generally circular plate 110 form and second mould form 170 defines a wedge-shaped profile 172 for defining the form of each channel 120a to be provided to the plate 110. In Figure fib, the first 160 and second 170 mould forms are brought together to define the overall plate form including the form of suitable channels. It will be appreciated that the second moulding form 170 can be readily withdrawn from the first trough form 160 after the moulding operation is completed.

Figures 7a and 7b show a second embodiment of the sweeping brush attachment herein comprising base plate 210 defining upper 212 and lower 214 planar surfaces and provided with fixing holes 211 for fixing to a mechanical sweeping machine. Thread- receiving channels 220a, 220b are provided to the base plate 210 in pair- wise, regular radial arrangement about the central axis 230 of the plate 210.

The upper surface 212 of the base plate 210 is further provided with ringshaped recess 216 for receipt of securing means in the form of a ring-shaped securing plate 250 having apertures 252a, 252b provided thereto, each arranged for off-set registration with the entry 222a, 222b to relevant channels 220a, 220b.

As shown in Figure 7b, bristle filaments 240a, 240b are received in threaded fashion at channels 220a, 220b of the base plate 210 and adjoining relevant apertures 252a, 252b of the securing plate such that the bristle ends thereof 242a, 242b splay out from the lower surface 214 of the base plate 210 to form a suitable overall sweeping brush form.

It will be appreciated that the securing plate 250 is also secured to the base plate 210 by the threaded action of the received brush filaments 240 that are wedged there within.

Each received brush filament is essentially wedged by forces acting at points A and B as shown on Figure 7b, and further guided to the required splayed out form by angled wall 228 of the base plate channel. To secure the brush attachment to a mechanical sweeping machine a fixing plate (not shown) of the sweeping machine fixes to the upper surface 212 of the base plate by means of screw-fixing using fixing holes 211 such that the fixing plate presses down on the protruding top parts of the brush filaments 240 thereby further securing them to the base plate 210.

In more detail, each channel 220a, 220b of the base plate 210 may be seen to have a particular tapered (or 'wedge-shaped') form wherein each entry hole 222a, 222b provided at the upper surface 212 of the base plate 210 has a larger diameter, and hence cross-sectional area than its corresponding exit hole 224a, 224b provided at the lower surface 214 of the base plate 210. Thus, each channel 220a may be seen to have a first part (i.e. a part of the wall of the channel) 226 that is essentially perpendicular to the plane defined by the base plate 210 and a second part (i.e. another part of the wall of the channel) 228 that defines an acute angle to the plane defined by the base plate 210. It may be seen that the second, acute-angled wall 228 of the channel acts such as to guide the received threaded brush filament 240 such that the desired splayed-out brush ends 242 configuration is adopted. It will also be noted that the walls 256, 258 of each aperture 252a of the securing plate 250 are shaped to match the tapering of its adjacent channel 220a of the base plate 210.

In use, the securing plate 250 is tightly secured to the base plate 210 by the forces acting on the brush filaments 240 threaded jointly therethrough. When however, the ends 242 of the brush filaments 240 become worn down, they may be replaced by holding onto the base plate 210 and withdrawing the securing plate 250 therefrom. The worn brush filaments 240 remain with the securing plate 250 and are thus removed en masse from the base plate 210, which is then rethreaded with fresh brush filaments 140.

Claims

Claims 1. A brush attachment for a mechanical sweeping machine comprising

a base plate, said base plate defining an upper and lower base surface; provided to the base plate and extending from said upper to lower base surface, plural channels for threaded receipt of brush filaments; reversibly receivable by the upper base surface of the base plate, a securing plate, said securing plate defining an upper and lower securing surface; and provided to the securing plate and extending from said upper to lower securing surface, plural channels for threaded receipt of said brush filaments, wherein upon threaded receipt of the brush filaments by the base plate and the securing plate the brush filaments are secured thereby such that filament ends thereof splay out from the lower base surface of the base plate.
2. A brush attachment according to claim 1, wherein the base plate has a generally circular profile.
3. A brush attachment according to either of claims 1 or 2, wherein the plural channels of both the base plate and securing plate are arranged radially and the radius defined by the plural channels of the base plate is greater than that defined by the plural channels of the securing plate.
4. A brush attachment according to any of claims 1 to 3, wherein the securing plate is a ring-shaped plate receivable within a ring-shaped recess provided to the upper base surface of the base plate.
5. A brush attachment according to any of claims 1 to 4, wherein the securing plate is provided with fixing means for reversibly fixing it to the base plate.
6. A brush attachment according to any of claims 1 to 5, wherein each of the plural channels of the base plate has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.
7. A brush attachment according to claim 67 wherein the tapered profile is generally wedge-shaped in cross-section.
8. A threaded brush attachment for a mechanical sweeping machine comprising a brush attachment according to any of claims 1 to 7 and received by the plural channels, brush filaments arranged such that filament ends of said brush filaments splay out from the lower surface of the base plate.
9. A threaded brush attachment according to claim 8, wherein the brush filaments comprise a plastic polymer or a metal.
10. A mechanical sweeping machine comprising a drive motor; and drivable in sweeping fashion thereby, a threaded brush attachment according to either of claims 8 or9.
11. A brush attachment for a mechanical sweeping machine comprising a base plate, said base plate defining an upper and lower surface; provided to the base plate and extending from said upper to lower surface, plural channels for threaded receipt of brush filaments such that filament ends of said brush filaments splay out from the lower surface of the base plate; and reversibly receivable by the upper surface of the base plate, securing means to secure said threaded brush filaments within said plural channels, wherein each of the plural channels has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.
12. A base plate for use with a brush attachment for a mechanical sweeping machine according to claim 11, said base plate defining an upper and lower surface; and provided to the base plate and extending from said upper to lower surface, plural channels for threaded receipt of brush filaments such that filament ends of said brush filaments splay out from the lower surface of the base plate, wherein each of the plural channels has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.
13. A base plate according to claim 12, obtainable by a moulding process.
14. A kit of parts for a brush attachment for a mechanical sweeping machine comprising (a) a base plate, said base plate defining an upper and lower surface, wherein the base plate is provided with plural channels extending from said upper to lower surface, said plural channels for threaded receipt of brush filaments such that filament ends of said brush filaments splay out from the lower surface of the base plate; (b) brush filaments for threaded receipt by the plural channels; and (c) reversibly receivable by the upper surface of the base plate, securing means to secure said threaded brush filaments within said plural channels, wherein each of the plural channels has a tapered profile such that the cross-sectional area of an entrance thereto at the upper surface of the base plate is greater than that of an exit thereto at the lower surface of the base plate.