Brush

This invention relates to brushes, particularly to paint brushes and cleaning brushes and more particularly to vibrating brushes.

One form of known vibratory paint brush is disclosed in US 2004/0205914. One aim of the present invention is to provide an improved vibrating brush.

According to one of its aspects, the present invention provides a paint brush in accordance with claim 1. Other aspects of the invention are defined in other independent claims. The dependent claims define preferred or alternative embodiments.

One embodiment of the present invention comprises an active brush ie a brush fitted with an integral vibration mechanism; in this case, the brush is preferably provided with an actuator to turn the vibration mechanism on or off. This may facilitate alternating between using the brush in an active, vibrating mode and using it in a passive, non-vibrating mode. An alternative embodiment of the present invention comprises a passive brush ie not having a vibration mechanism.

Where a tapered connection is provided between a detachable brush head and a handle it is preferably self holding or self locking; it is preferably the only means provided for retaining the detachable brush head and the handle together. A self holding or self locking taper connection may be particularly advantageous for a vibrating brush as it may alleviate the tendency of other forms of connection (for example cylindrical screws or clips) to vibrate and/or work themselves loose. Furthermore, such a connection may ensure that the available vibrational energy is transmitted through the connection without loss of vibrational energy in or due to the mechanical fixing.

The connection between a detachable brush head and the handle is preferably provided by an interaction between surfaces as opposed to a point contact or series of point contacts. This may provide stability and or rigidity to the connection.

A cone form of connection may facilitate mounting and dismounting of the detachable brush head, for example using a slight rotation. It may also permit the user to select the orientation of the detachable brush head with respect to the handle. This may be particularly useful when using a flat form of brush head; when a user grips the handle in any particular way, the cone form of connection allows the rotational position of the brush head to be orientated at will relative to the handle. This may provide a more comfortable painting position.

The connection between the handle and the brush head is preferably a cone-in- cone connection. A morse cone may provide a particularly convenient form.

A connector having the form of a bore may be at greater risk of damage than a connector having the form of a trunion, especially in respect of the lip of the bore when made of a plastics material. Arranging for the tapered handle connection surface to be provided on a trunion may reduce the risk of damage to the handle; a damaged brush head may be more easily replaced than a damaged handle, especially when the handle incorporates a vibrating mechanism.

The taper length may be within the range 10 to 30mm and/or the taper angle may be within the ranges 0.5 ^> to 12.5 ^> , P to 25 ^> , P to 2Or 2 to 4°. Such configuration may facilitate assembly and/or disassembly and/or self locking of the connectors.

Particularly in the case of a passive paint brush, the handle may comprise wood or plastics. It may comprise an injection moulded plastics and/or a combination of plastics, for example a resilient plastics core and a softer plastics contact surface adapted to provide an agreeable feel or touch for the user.

Providing at least one of the tapered connection surfaces on a lining, for example a plastics or metal lining may:

• facilitate selection of a desired friction characteristic, hardness and/or resilience;

• allow the tapered connection surface to be removable and/or replaceable;

• facilitate incorporation of the tapered connection surface by allowing this to be provided on a separate piece rather than as an integral part of the handle or brush head.

Where a damper is provided this may provide sufficient damping to allow a paint brush to be used comfortably in its vibrating mode and sufficient rigidity to allow such a paint brush to be used as an ordinary, non-vibrating paint brush. This may allow: • the vibrating mode of the brush to be used for delicate painting portions, for example painting of a straight line, painting up to a border (for example the edge of a wall mounted light switch or cornice); and

• the non-vibrating mode to be used for applying paint more quickly away from such delicate portions. This may increase the overall efficiency of applying paint to walls, panels, doors and other surfaces. Furthermore, the facility and accuracy afforded for precision painting may

• allow non-professional decorators to easily carry out such painting; and/or • allow professional decorators to complete such precision painting in a manner that is less tiring and/or quicker.

The nature of any vibration provided is preferably such that:

• The paint has a tendency to move towards the free end of the bristles to facilitate accurate application to a surface; • Use of masking paper or tape can be reduced or eliminated;

• The paint is retained within the brush head and will not spatter.

The weighted displacement of the brush head relative to the handle, particularly the grip portion of the handle, when subjected to an external force may provide one indication of the brush's suitability for use in a non-vibrating mode. This may be assessed by maintaining the grip portion of the handle horizontal, suspending a mass of 400g on a wire from the brush head at a

position corresponding to the root of the bristles and measuring the angle of displacement of the brush head relative to the grip portion of the handle. The suspended mass of 40Og is representative of the force that will be exerted on the brush head when the brush is used for painting in a passive, non-vibrating mode. A displacement of less than 18P, preferably less than 15° provides desirable passive painting characteristics. The displacement may be greater than 5Or greater than 8P. These characteristics may be provided essentially by the damper and/or by the damper in combination with the way it is secured to the handle.

The held vibration sensation may be:

• Less than 35%, preferably less than 30%; and/or

• Greater than 10%, particularly greater than 15%; of the full vibration.

This ensures that: • the vibration felt by a user holding the grip portion of the handle is not uncomfortable or unduly tiring;

• there is suitable separation between the grip portion of the handle and the active portion of the handle to allow adequate vibration of the brush head; and • the vibration of the active portion of the handle is transferred primarily to the brush head and not "lost" in vibrating the grip portion of the handle.

An explanation of measurement of the held and full vibration is given in relation to the accompanying figures.

Particularly in the case of a paint brush, the bristles of the brush head may comprise a mixture of synthetic bristles and natural bristle, for example of pig hair. The bristles may comprise:

• between 15% and 45% synthetic bristles (preferably between 20% and 40%); and

• between 55% and 85% natural bristles (preferably between 60% and 80%);

The synthetic bristles may facilitate precision for application of paint to a surface and the natural bristles may provide advantageous paint retention and/or capillary action. This combination may be particularly advantageous in respect of a vibrating paint brush to ensure that the paint has a tendency to move towards the free end of the bristles to facilitate accurate application to a surface and yet is retained within the brush head and will not spatter.

Alternatively, the bristles may consist of synthetic bristles.

The bristles may be:

• greater than 35mm, preferably greater than 40 mm in length; and/or

• less than 100mm, preferably less than 80mm, more preferably less than 65 mm in length.

This may provide a suitable amount of resilience and/or movement and/or resonance in the bristles to enhance any vibration movement.

In the case of a rectangular form brush head the bristles are preferably between 35 mm and 55 mm in length.

In the case of a cylindrical form brush head, the bristles are preferably between 50 mm and 70 mm in length.

The bristles of a rectangular form brush head may form a brush head having

- a bristle width of:

• Greater than 20mm, preferably greater than 25, more preferably greater than 30 mm; and/or

• Less than 100mm, preferably less than 80mm, more preferably less than 70mm; and/or

- a bristle thickness

• Greater than 5mm, preferably greater than 8 mm, and/or

• Less than 30 mm, preferably less than 20 mm, more preferably less than 15 mm.

The bristles of a cylindrical form brush head may form a brush head having a diameter:

• Greater than 10mm, preferably greater than 15 mm, and/or

• Less than 25 mm, preferably less than 22 mm, more preferably less than 20 mm.

The length of bristles defined above is the free length, particularly the length projecting from a ferrule or attachment securing the bristles in place. The thickness, width and diameter are those at the base of the bristles.

The combination of desired dampening and rigidity of the damper when assembled in the brush may be achieved by a damper which comprises or consist essentially of a material having a shore hardness in the range 45 to 75, preferably 50 to 60. The dampening/rigidity properties may also be influenced by the fixation of the damper to the handle. Preferably, the damper is secured to the handle by a gripping or clamping arrangement, more preferably between plates or flanges. Contact between the damper and the handle may be arranged around the entire or substantially the entire periphery of the damper. This may help to maximise the contact between the damper and the handle. Arranging the damper to be of substantially cylindrical cross section may facilitate mounting and/or contact with the handle. Whilst an adhesive may be used, assembly is facilitated if no adhesive is used in the damper mounting.

Arranging for at least one stop to be provide, preferably as part of the damper, may reduce the risk of the damper becoming damaged or dislodged, for example, by excessive movement between the parts of the handle to which it is attached. The stop or stops preferably act over 36CP, i.e. they are effective at each position around the perimeter of the brush to limit the angle of displacement between the active and grip portions of the handle.

A vibration movement which comprises a translation, possibly as part of a rotational movement, may provide an effective vibration action.

The vibrator may comprise a motor having an eccentric mass connected to its spindle. The axis about which the eccentric mass rotates is preferable co-axial

with the handle; it is preferably coaxial with the length of the bristles of the brush. The vibrational movement of the bristles is preferably substantially perpendicular to their length.

A motor adapted to rotate at a speed within the range 6000 to 8000 rpm, having a mass in the range 5 to 7 g, preferably 5.2 to 6.3g arranged with an eccentricity with respect to the axis of the motor within the range 2 to 4 mm may provide a particularly advantageous form of vibration, particularly for painting applications.

A motor adapted to rotate at a speed within the range 7000 to 10000 rpm with a mass in the range 5 to 7 g, preferably 5.2 to 6.3g arranged with an eccentricity with respect to the axis of the motor within the range 2 to 4 mm may provide a particularly advantageous form of vibration, particularly for cleaning applications.

The direction of rotation of the motor may be selectable by the user, for example by means of a switch.

An amplitude measured at the root of the bristles in the range 1.5 to 3.5 mm, preferably in the range 2 to 3 mm and a frequency in the range 60 to 100 Hz, preferably 75 to 85 Hz may provide a particularly advantageous form of vibration, particularly for a paint brush.

An amplitude measured at the root of the bristles in the range 2 to 4 mm, preferably in the range 2.5 to 3.5 mm and a frequency in the range 80 to 120 Hz, preferably 90 to 110 Hz may provide a particularly advantageous form of vibration, particularly for a cleaning brush.

The vibration of the brush, brush head or bristles may be a vibration obtainable with any of the configurations described herein.

The brush, when configured as a paint brush, may be used with one or more of: acrylic paint; glycarophtalic paints; water based paints; resin based paints; solvent based paints; varnishes; paints in gel form. Paint brushes according to

the invention are particularly useful for decoration eg applying paint to walls, doors, window frames and building panels.

The brush may be adapted to be used with a plurality of interchangeable brush heads; these may be selected from paint brush heads, cleaning brush heads, polishing brush heads.

A particularly advantageous configuration in accordance with the invention is the combination or association of (i) a handle having a handle connector and/or (ii) a brush head having a head connector and/or (iii) a brush head receptacle, in which the handle connector and the head connector are configured to permit assembly, retention and disassembly of the handle and the brush head, and in which the brush head receptacle comprises an attachment adapted to releasably retain the brush head within the receptacle.

One use of such a configuration is in relation to paint brushes. A sequence of painting using such a configuration may comprise one or more of the steps of:

- fitting a first paint brush head to the handle and completing a first painting task (for example using a rectangular paint brush head to paint a substantially straight portion of a wall adjacent to a cornice);

- disassembling the first paint brush head from the handle and storing the first paint brush head in a brush head receptacle; - fitting a second paint brush head to the handle and completing a second painting task (for example using a round paint brush head to paint a corner of a wall adjacent to a cornice);

- disassembling the second paint brush head from the handle and storing the second paint brush head in a brush head receptacle; - removing the first paint brush head from its receptacle and re-assembling it with the handle for use in a third paining task.

Any aspect of this invention may be used alone or in combination in relation to various brushes, particularly paint brushes and cleaning brushes.

Embodiments of the invention will now be described, by way of example only, with reference to:

Figs 1 and 2 - schematic perspective drawings of an assembled, active paint brush;

Figs 3 and 4 - perspective drawings of detachable heads for the brush of Figs 1 and 2; Fig 5 - a cross sectional view of a passive, non-vibrating paint brush handle;

Fig 6 - a cross sectional view of the handle of Fig 5 assembled with a detachable brush head;

Fig 7 - a cross sectional view of an alternative passive paint brush handle;

Fig 8 - a perspective view of a brush head adapted for use with the handle of Fig 7;

Fig 9 - a perspective view of the active brush of Figs 1 and 2 with the brush head removed;

Fig 10 - a partially cut away perspective view corresponding to Fig 9;

Figs 11 and 12 - partially cut away perspective views showing the attachment between a brush head and a portion of the handle;

Fig 13 - a perspective view of a damper;

Fig 14 - a representation of the movement of the bristles;

Fig 15 - a representation of the movement of the brush head;

Fig 16 - a schematic perspective view of a brush suspended for measuring vibration;

Fig 17 - a perspective view of use of a flat brush head;

Fig 18 - a perspective view of use of a round brush head;

Fig 19 - a schematic cross section of a round brush head in a storage receptacle; and Fig 20 - a schematic cross section of a flat brush head in a storage receptacle.

Fig 1 shows a vibrating paint brush 10 having a handle 11 and a detachable head 42 (shown schematically in dotted lines). The handle 11 comprises an active portion 13 housing an integral vibrator and a grip portion 14 separated by a damper 15. The grip portion 14 of the handle 11 houses one or more batteries, preferably rechargeable, to power the vibrator via an on/off switch 105. Alternatively or additionally the vibrator may be powered by an external electrical power source.

The detachable brush head 42 has its bristles 43 arranged as a round or conical brush head and is attached and secured to the active, vibrating portion 13 of the handle 11 by cooperation between a morse cone trunion provided at the end of the handle 11 and a corresponding morse cone bore provided within the brush head 42.

In use, a painter will generally hold the grip portion 14 of the handle 11. The vibrator may be activated particularly to facilitate application of paint in a border zone along a border or at in intersection between two surfaces. The vibrator may be turned off and the brush used as an ordinary paint brush, for example, to apply paint from the border zone towards a large area to be painted. The remaining, large surface may then be painted with a roller.

Fig 2 show a similar paint bush, save that it is fitted with a detachable brush head 32 having its bristles 33 arranged as a substantially flat or rectangular brush.

The term flat brush head is intended to denote a generally rectangular form of brush head, for example as illustrated in Fig 3. The term round or circular brush head is used to denote a generally round or cylindrical from of brush head, for example as illustrated in Fig 4. Such round brush heads generally have a tapered portion 44 finishing in a point 45

Figs 5 and 6 illustrate the connection between a wooden handle 51 and a detachable brush head 62. The handle 51 has a tapered handle connection surface 54 in the form of a morse cone provided as a plastics lining secured, for example by adhesive, to the handle 51. Alternatively, the handle connection surface 54 may be provided as an integral part of the handle 51.

The detachable brush head 62 has a head connector 63 having a tapered head connection surface 64 corresponding in form and angle to the tapered handle connection surface 54.

Fig 7 and 8 illustrate a similar connection arrangement between a handle 71 and a flat form detachable brush head 82. One or both of the connectors 73, 83 may be of a moulded plastics material.

Figs 9 and 10 again illustrate the active 13 and grip 14 portions of the handle 11 connected by the intervening damper 15. A tapered handle connection surface 101 in the form of a morse cone is provided on the active portion 13 of the handle. The active portion 13 of the handle houses an integral motor 102 having an eccentric mass 103 attached to its spindle. Advantageously, the rotating mass rotates within at least a portion of the connection cone provided by connection surface 101. Consequently, the source of vibration is arranged towards, substantially adjacent to or indeed at the position of the roots of the bristles of a brush head attached to the handle. This provides a particularly advantageous transmission of vibration to the brush head and/or bristles.

The motor 102 is powered by batteries housed within the grip portion 14 of the handle via an on/off switch 105 and wire (not shown) which passes through a bore 151 of the damper. The batteries 14 may provide a counterweight to the motor 102 to make the handle more comfortable to hold and manipulate, for example by being spaced from the damper 15 by an intervening space 106. An alternative or additional counterweight may be provided.

Fig 11 shows the attachment between the morse cone 101 connector of the active portion 13 of the handle and a corresponding tapered head connection surface 111 of a head connector 112 of the detachable brush head 32. The taper length tl is about 20mm and the taper angle ta is about 2?. The term taper angle signifies the inclination of the tapered surface with respect to a principle axis 199.

In Fig 12, the direction of the length of the bristles is represented by z. The direction of vibration of the brush head and/or the bristles is essentially orthogonal to the length z, that is to say substantially parallel to a plane intersecting axes x and y. Particularly in the case of round brush heads, the bristles tend to splay outwardly from their point of attachment. In this case, the direction of length of the bristles should be understood as that of the central or un-splayed bristles. The movement is preferably multidirectional that is to say the movement is primarily one of vibration or micro-vibration rather than simply a rotation such that the bristles, and particularly ends of the

bristles, travel in a variety of x and y directions and preferably have a movement which is circular or oval on form, the angular velocity of bristles towards the centre of the brush head being substantially the same as the angular velocity of bristles toward the exterior of the brush head. This would not be the case with a simple rotating head.

In the Fig 12 embodiment, the length of the brush head 120 is 83 mm and the exposed length of the bristles 121 is 48 mm. The quotient (exposed length of bristles 121) / (length of brush head 120) may be at least 0.5, preferably at least 0.55 or at least 0.6. In the Fig 12 embodiment it is 0.58. One significance of this quotient is that it expresses the concept of preferably arranging an interconnection 122 between the head connector 112 and the handle connector 101 in close proximity to the base of the bristles. It also expresses the concept that the total length of the brush head is no greater than twice the exposed length of this bristles. This is of significance with respect to storage of brush heads using receptacles described herein; the primary function of such receptacles may be to retain and/or protect the bristles and such receptacles may be configured to be relatively compact when the aforementioned conditions are satisfied.

The damper 15 shown Figs 10 and 13 comprises a moulded, synthetic rubber material having a shore hardness of about 60. It has a first connection portion 91, a second connection portion 92 and an intervening portion 93. The first connection portion 91 comprises a cylindrical connection flange 94 adapted to be secured to the active portion 13 of the handle by means of an interference or clamp fit between a damper connection surface 95 and a damper connection flange 96 which projects inwardly from the periphery 97 of the handle. A similar arrangement connects the second connection portion 92 to the grip portion 14 of the handle.

The intervening portion 93 of the damper 90 comprises a first stop 98 and a second stop 99 in the form of spaced flanges which project from the body of the damper toward the periphery of the handle 97 and are separated by a recess 141. These stops 98, 99 provide a physical limitation to possible

rotational displacement between the active 13 and grip 14 portions of the handle if the grip portion 14 of the handle is moved in direction 142 and the active portion 13 of the handle is moved in direction 143 so as to pivot about the damper 15. The circular nature of the stops 98, 99 enables them to act irrespective of the orientation of such bending about the axis 144 of the handle.

Fig 14 represents the vibration characteristics measured at the root of the bristles of a bush head of the paint brush. This may be measured by cutting the brush head at the position of the roots of the bristles, arranging for the path of a light beam to be cut by the vibration movement (indicated at R) and measuring the amplitude and frequency of vibration. Fig 14 represents

• a rest position 152 of this portion of the paint brush before the vibrator is turned on,

• that when the vibrator is turned on the bristle roots initially have a spiral movement 153 orthogonal to their length, • that when the vibrator is stable, each bristle root has a substantially similar movement 154 orthogonal to its length which, when allowed to move freely, is substantially circular with an amplitude a of about 2mm and a frequency of about 80 Hz.

When the vibrating brush head is placed against a surface to be painted for example with the bristles at about 45° to the surface, as represented schematically in Fig 16, the free circular movement is deformed and becomes a flattened circular or oval movement 161. This give the vibration brush head a tendency to advance by itself along a surface to be painted.

Fig 16 shows a paint brush 10 suspended vertically by opposed point contacts 171, 172 by the damper 15. The full vibration is measured as the amplitude of vibration of the active portion 13 of the brush measured at a position 173 corresponding to the position of the roots of the bristles of a brush head attached to the brush. The held vibration sensation is measured as the amplitude of vibration at a position 174 at the grip portion of the handle at a distance vd of 5cm from the position at which the damper 15 is held. This

position is representative of the position at which a user will generally hold the brush when in use.

The holding structure of the contact points 171, 172 (which may be metal spikes) is arranged and given a suitable inertia such that it does not significantly affect the vibration characteristic being measured.

The following results were obtained measured for two different dampers:

Fig 17 illustrates a flat brush head 32 used in the active mode of a vibrating brush to paint the precision portion of the edge of a surface 181 at its intersection with a cornice 182. The brush head is held up against and substantially perpendicular to the intersecting edge and at an angle of about 45° with respect to the plane of the surface 181 and the surface 184 of the cornice. The precision of the vibrating brush is such that is it not necessary to mask the surface 184 of the cornice and substantially no paint is deposited on that surface. The flat, vibrating brush head is particularly adapted for painting line intersections of planes.

Fig 18 illustrates a round brush head 43 used in the active mode of a vibrating brush to paint an internal corner portion 191 at the intersection of a surface and first 192 and second 193 planes. The brush head 43 is held at about 45° to each of the planes 192, 193 so as to be able to access the corner portion 191 and apply paint to the surface without applying paint to faces 192 or 193.

Fig 19 shows a substantially cylindrical storage and/or cleaning receptacle for a brush head. The receptacle 200 comprises a container portion 205 having sidewalls, a base 207 and an open end 206. The open end 206 is adapted to be closed by a lid 208 by a snap fit connection provided by a projection 211

provided around the peripheral edge of the side wall of the container portion 205 and a cooperating clip 212 provided around the periphery of the lid 208. An additional seal (not shown) between the receptacle 200, and the lid 208 may be provided. When closed with the lid 208, the receptacle 200 is preferably watertight. Alternatively, the connection between the lid 208 and the container portion 205 may be provided by a screw fit connection, which may be a bayonet type connection.

The lid 208 comprises an attachment 209 adapted to removeably secure the lid 208 and a paint brush head 201 together. In this embodiment, the attachment 209 comprises a tapered connection surface 210 in the form of a cone adapted to cooperate with a corresponding, conical tapered connection surface 203 of the paint brush head 201. The lid 208 may be easily removed from the container portion 205 to allow the lid 208 and the paint brush head 201 to be assembled or disassembled.

In use, the paint brush head 201 is suspended from the attachment 209 of the lid 208 such that its bristles 202 do not touch the base 207 of receptacle 200. Preferably, the receptacle 200 stands on its base. However, in preferred embodiments, even if the receptacle 200 falls over or sits on its side, the bristles 202 of the paint brush head 201 do not touch the walls of the receptacle 200.

Fig 20 shows a flat brush head suspended from the lid of a receptacle which contains water or a cleaning or wetting fluid up to a level 214 to substantially cover the bristles of the brush. The receptacle may be substantially cylindrical or it may be substantially rectangular in cross section.

Graduations 213 are provided at the side wall of the receptacle to indicate a suitable level to which a liquid may be introduced prior to inserting a brush head. The different graduations may take account of the different displacement of different sizes of brush heads that may be placed within the receptacle.

The receptacle may be used for temporary storage of a paint brush head prior to reuse, for example to facilitate storage without drying of a brush head whilst a decorator uses an alternative brush head or takes a break. This may avoid the necessity of cleaning the brush head prior to reuse in such circumstances or wrapping it in a rag or in plastic film. The receptacle may be used for cleaning or partial cleaning of a brush head, the paint attached to the bristles having a tendency to fall to the base of the receptacle when suspended in water or another suitable cleaning fluid. A receptacle containing a brush head and a cleaning fluid may be agitated, for example shaken, and/or left to settle to facilitate this. The receptacle may also be used for more permanent storage of paint brush heads, either with or without the presence of a liquid, the absence of contact between the bristles and the receptacle being advantageous for avoiding deformation of the bristles.

The Fig 20 receptacle is provided with a suspension attachment 215 which, in this embodiment, is integral with the lid 208. The suspension attachment 215 may allow the receptacle to be hung for example from a hook or rail, for example for storage or for display. The suspension attachment 215 may be foldable such that it may lie against or within the lid 208; this may facilitate stacking of one receptacle on another.

The distance 216 between the base 207 of the receptacle and the bristles of a brush retained at in the receptacle by the attachment 209 may be greater than 5mm or 10mm; it may be less than 40 mm or 30 mm. Such a configuration may provide a space separated from the bristles at which sediment may collect; it may enable a compact configuration of the receptacle.

Whilst a receptacle has been described in relation to a particular paint brush, receptacles may be may be used with other types of bushes and/or brush heads.