This application claims priority to U.K. Application No. GB0722694.7, filed 20 Nov. 2007, by the same inventor, the entire contents of which hereby incorporated by reference.
The present invention relates to strip brushes.
Strip brushes generally comprise an elongate spine member, within which a plurality of bristles are held such that a free end of each bristle depends therefrom.
Such strip brushes are conventionally manufactured in a continuous production flow in which a length of spine material is deformed so as to trap bristles therein. The resulting lengths of strip brush are then cut to the desired length and crimped at each end to form discrete brushes. The substantially rigid spine allows attachment of the brushes to machinery or manual tools.
The strip brushes produced by this method of manufacture are used for a broad variety of applications across different industries. Numerous applications provide for the use of this form of brush as a sealing member, for attachment to moving machinery. The plurality of tightly packed bristles form a mechanical barrier which substantially inhibits the flow of particulate and/or fluid materials therethrough, dependent on the bristle arrangement and material.
In one example, polymer bristles may be provided so as to provide a hygienic seal for use in food handling or processing machinery. In another example, the bristles may be formed of metallic strands. Such an arrangement finds one application in the oil and gas industry for use as a mechanical seal for machinery in pipelines. Regardless of the industry requirements, the strip brushes are manufactured in substantially the same manner, such that lengths of strip brush are cut to the required dimensions for the application at hand.
During use, the free ends of the bristles are typically maintained in contact with an adjacent surface. This causes a contact force such that the bristles can bend or flex in response thereto to maintain the required seal or brushing effect. However, it has been found that the application of contact forces and/or vibrations to the strip brush during use can result in a number of bristles towards the peripheral edges of the strip brush becoming loose and shedding from the ends of the brush.
The shedding of bristles in this manner causes a problem since they can enter the flow of material through the machinery or the moving parts of the machinery itself. When one considers the use of the strip brushes on food handling equipment or else within fuel pipelines, it will be appreciated that the entrainment of loose bristles into the material being processed is a significant disadvantage which can lead to processed materials being rejected or machine down time.
It is an object of the present invention to provide an improved strip brush for which the problem of shedding bristles is alleviated.
According to a first aspect of the present invention there is provided a strip brush comprising a plurality of elongate bristles and a spine formation, the bristles having first and second free ends and being gripped by the spine formation between said ends, wherein the spine formation comprises a length of material having first and second spaced folds and the plurality of bristles are trapped between said folds such that the first and second folds define opposing ends of said spine formation, and wherein the spine formation of formed of a single sheet of planar material which is folded and/or otherwise deformed into the required profile.
The present invention allows for continuous folded ends of the strip brush in contrast to the discontinuity formed by cut and crimped brush ends. The folded ends of the strip brush are particularly advantageous since the bristles cannot be worked free of the ends during use. Thus the spine forms a loop about the plurality of bristles, trapping the bristles within the spine during use.
In one embodiment, the first and second folds are substantially parallel with the bristles. The length of spine material may comprise a spine member which may be elongate in shape. The spine member may have a longitudinal axis and the spine member may be folded about first and second axes or fold lines which are substantially perpendicular to the longitudinal axis so as to form the first and second folds.
The spine member may have opposing edges which meet or overlap part way along the length of the strip brush once formed. The spine formation may therefore comprise a single discontinuity part-way along the length of the spine member rather than at the ends of the brush once formed.
The spine member may be shaped to provide a first and second opposing wall portions extending between said folds with the bristles disposed therebetween.
In one embodiment the spine formation is shaped in the form of a trench or channel within which the bristles are held. The first wall portion of the spine member may comprise an outer wall of the channel and the second wall portion may comprise an inner wall of the channel. The channel typically has a base and opposing side walls which define an elongate slot or opening through which the bristles protrude. The channel may be substantially U-shaped in section. The opening may be of smaller width dimension than the base of the channel.
The bristles are typically bent or otherwise deformed within the spine.
The spine member may be formed of a strip of material of substantially uniform width which is folded or otherwise formed into the required shape. Alternatively, the spine member may have a first section which forms the first wall portion which is of greater width than one or more further portions which form the second wall portion.
In one embodiment, a spine support member is provided. The spine support member may take the form of an outer wall member shaped to surround the spine formation. The spine support member is typically of greater strength and or stiffness than the spine formation material and may be shaped to provide for attachment of the strip brush to machinery for use.
According to a further embodiment of the present invention there is provided a method of manufacture of a strip brush comprising: arranging a plurality of bristles relative to a spine member, formed of a single sheet of planar material, such that first and second ends of the bristles protrude outwardly from the spine member; and providing first and second spaced folds in the spine member such that the spine member surrounds said bristles at a location between said first and second bristle ends wherein said first and second folds define opposing ends of the spine member.
The spine member may comprise a length of material having opposing first and second edges, wherein the edges meet or overlap when the first and second folds are provided.
The first and second folds may be positioned so as to provide a strip brush of predetermined length without the need for cutting the brush to size.
In one embodiment, the spine member is further folded or deformed in an orientation substantially perpendicular to the first and/or second folds. The third fold or deformation may be substantially along the length of the spine. The spine member may be deformed such that it is substantially channel shaped in section. The cross-sectional shape of the spine once formed may be substantially V-shaped or U-shaped or rounded in the form of a partial ellipse or a horseshoe shape.
Further preferable features of the present invention are defined within the claims.
One or more specific embodiments of the present invention are described in further detail below with reference to the accompanying drawings, of which:
Turning firstly to
The bristles 12 are elongate in shape and have free ends 16 spaced from the spine formation 14. The spine formation comprises an inner 18 and outer 20 wall formed of a single piece of resilient material as will be described below. The outer wall 20 is substantially U-shaped or horseshoe shaped in section so as to form a channel or gulley within which the bristles 12 are located.
The inner wall 18 is positioned within the outer wall 20 and is correspondingly shaped. The inner wall 18 is substantially concentric within the outer wall 20 with the bristles trapped therebetween. It will be appreciated that the channel formed by the outer wall 20 is of slightly greater width than the inner wall such that it can accommodate the inner wall and the bristles therein. The channel of the outer wall 20 has an opening 22 which is elongate in form when viewed from above and through which the bristles extend.
A mid portion 17 of the bristles 12 is held tightly in the spine formation 14 between the inner 18 and outer 20 walls. In this embodiment the mid portion 17 is substantially equidistant from each end 16 of the bristles 12 such that each free end 16 of the bristles extends to substantially the same distance form the spine formation 20. The embodiment of
However, it will be appreciated that the bristles may be held within the spine formation 14 at any point between the opposing ends of the bristle and need not be held about their mid point 28. The plurality of bristles 12 may be considered to be a collection or else a semi-ordered array in which the orientation of each bristle is substantially fixed, although the exact position of each bristle is subject to change dependent on the interaction between bristles during manufacture. The collection of bristles typically has a width dimension which is greater than its depth and, more typically, the collection has a width dimension (which corresponds to the length of the strip brush) which is an order of magnitude or more greater than the depth.
It will also be appreciated that, whilst the channel shape of the spine formation is formed by bending of the inner and outer walls at a pair of locations equidistant from the axis 26, a single bend could be provided or else two or more bends or folds which are not symmetrical about the axis 26.
The trapped section 17 of the bristles 12 is deformed within the outer wall 20 about the inner wall 18 such that it conforms substantially to the shape of the channel.
In use the spine formation provides a substantially rigid portion of the brush which can be use to attach the brush 10 to machinery or the like.
The spine formation 14 is formed of a resiliently deformable material, which is typically a metal such as mild steel. Other materials can be used dependent on the brush specifications.
Turning now to
A plurality of bristles 12 (see
The spine material 30 is deformed about spaced fold lines 34 and 36 so as to produce folds 35 and 37, resulting in the profile shown in
The folds 35 and 37 are spaced by a distance A which defines the length of the spine formation 14. The outer regions 38 and 40 are folded over in the form of flaps which are folded back upon the central portion substantially about 180°. The length A and the length of the outer regions 38 and 40 are selected such that the formed flaps overlap when folded flat as shown in
In one embodiment the spine material may be folded by approximately 95° or else until the opposing edges of the inner wall 18 touch. In alternative embodiments, the spine material may be longitudinally folded by less than 90° so as to form an open channel or V-shaped section.
The folding of the spine material in this manner causes the bristles to be bent back upon themselves such that the free ends 16A and 16B protrude from the spine formation 14 in substantially the same direction. Whilst two longitudinal folds 44 and 46 are preferably use to achieve this effect, a single longitudinal fold of approximately 180° may also be used. A single or a plurality of folds may also be tailored to deform the spine material about a curved sectional shaped such that it is rounded in section. All such embodiments are intended to fall within the scope intended by the terms “fold,” “folded,” or “folding.”
It will be appreciated that the inner 18 and outer walls 20 of the spine formation in
The folds of
The support formation 48 provides additional strength and rigidity to the spine of the brush and may be provided with a particular profile in order to be fixable within a correspondingly shaped slot on a machine. In one embodiment, the shaping of the spine in this manner allows simple fixation of the strip brush to a machine or device for use without the need for additional fixing means. However, it will be appreciated that conventional fixing means may also be provided.
In
The support member 48 may have straight or angled sides or else may be bulbous or rounded in section as shown in
The spine support 48 may be preformed into an open tubular arrangement as shown in
Turning now to
The spine material 54 has a central region 56 and outer regions 58 and 60 which are folded about folds 62 and 64 to form overlapping flaps. However, the outer regions or flaps 58 and 60 in
The spine formation 66 of
Other features of the embodiment of
Any or all fold lines described above need not be marked or otherwise indicated on the spine material 30. Alternatively any or all fold lines may comprise marked lines of predetermined spacing or else may be embodied by physical features on the spine material such as by way of indents, lines of weakness, sections of increased thickness or the like.
Number | Date | Country | Kind |
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GB 0722694.7 | Nov 2007 | GB | national |