A HANDLE FOR A PAINT BRUSH

The present invention is concerned with handles for paint brushes. In particular, the present invention is directed towards a handle for a paint brush which has improved ergonomic properties.

Traditionally, paint brushes comprise a handle having a brush located at one end thereof. The handle is typically connected to the brush head such that the brush head lies symmetrical with respect to the handle. The handle is typically elongate and extends away from the brush head in a straight rod-like manner such that its cross-section is substantially circular. Such handles are known as dagger-type handles in the art. Alternatively, the handle may have substantially flat major opposed surfaces such that its cross-section is substantially rectangular. Typically, the handle and brush head are located substantially in the same plane such that they are coaxial and coplaiiar with one another.

A known problem with traditional paint brushes is that a user's hand and arm may become tired after a certain period of time and therefore it is desirable to have an improved ergonomic handle to reduce hand fatigue.

US2004/0231083 discloses an ergonomic paint brush in which the handle has a curved shape. The handle, brush head and bristles thereof are all substantially coplanar with one another. However, the handle is not coaxial with the brush head

and the bristles. Rather, the handle is curved in the same plane that the brush head lies in.

Although handles for paint brushes are known, as discussed above, which do not conform to the traditional form there is still a requirement for an improved ergonomic handle for a paint brush which reduces hand fatigue.

In one aspect the invention provides an ergonomic paint brush handle, the handle having an elongate body for receiving a brush at one end thereof so that the brush lies in a notional brush plane, the body having a median plane lying along the length thereof and transverse to the brush plane, wherein the body is curved in the median plane.

It is possible for a part or the whole of the body to be curved. In one embodiment the handle body is substantially continuously curved in the median plane such that no part of the handle is planar and parallel to the notional brush plane.

The handle body may have first and second opposed major surfaces. The first major surface may be convex in the median plane such that it is continuously curved. The second major surface may be concave in the median plane so that it has a surface which is approximately parallel to the first major surface. However, in one embodiment only one of the two major surfaces may be curved (either convex or concave) with the other opposite major surface being planar and lying in the brush plane.

If the two major opposing surface are both continuously curved then they may be substantially parallel to one another with the same radii of curvature, such that they both take the form of an arc from the same circle. Alternatively, they may have differing radii of curvature such that they take the form of arcs from circles with different radii. For instance, the convex surface may have a radius of curvature which is less than the radius of curvature of the concave major surface. In such a case the two major surface would taper towards one another. In one embodiment this tapering effect is found towards the distal (opposite to the end for receiving the brash) or tail-end of the handle.

For the purposes of this application, the width of the handle is defined as the dimension across the handle body as measured parallel to the brash plane. In one embodiment, this width may vary along the length of the handle.

The handle may have a first width at the end for receiving a brush, a second width at the opposite end of the handle thereof (i.e. at the distal or tail end of the handle) and a waist provided therebetween. In one configuration, the first width is substantially equal to the second width and the width of the waist is considerably smaller than the first or second widths. The width of the waist may in fact be less than 35% of the first and second widths.

In use, the handle may be held in a user's hand such that the waist of the handle is supported by the junction of the thumb and forefinger of the hand.

The waist may be provided at a point which lies equal to or more than half way along the length of the handle distal from the end for receiving the brush.

The shape of the handle may in fact be generally pisciform when viewed along the median plane and transverse the longitudinal length of the elongate body.

The shape of the tail end of the handle, opposite to the end for receiving the brush, may be wedge-, sector-, or fan-shape as viewed along the median plane and transverse to the longitudinal lengths of the elongate body. This tail may rest on the back of the hand anterior (i.e. towards the wrist) of the junction of the thumb and forefinger which supports the waist of the handle.

The tail end may be resiliently flexible in that it may be bent or twisted with respect to the handle so that upon release of a bending force the tail may return to its initial shape, configuration and orientation with respect to the handle. This resilient flexibility provides for greater comfort (compared to a handle having a rigid inflexible body) since it will flex with the movement of a user's hand in use. The tail end may have rounded corners further improve the comfort.

The handle may be manufactured at least in part from a thermoplastic elastomer and in one embodiment may have a solid core encapsulated by the thermoplastic elastomer for improved comfort. This core may extend along the whole longitudinal length of the handle body or may only extend part way along from the end for receiving a brush towards the tail end. Consequently, the resilient

flexibility of the handle may vary along the longitudinal length thereof from a more rigid state at the end for receiving the brush to a less rigid state towards the tail.

The handle according to the invention may be formed so as to be ambidextrous in that it may be held in both a left and a right hand with equal effectiveness, symmetry and comfort. This may be because the handle is symmetrical about the median plane.

In a further aspect, the invention provides a handle for a paint brush which has the shape of the anterior three-quarters (i.e. from the flipper to the tail) of a whale.

This shape may in fact more closely resemble the shape of the anterior three- quarters of a humpback whale. A humpback whale is so-called because when it comes to the surface of the sea and then dives back down its back arches in the shape of a hump. The tail is the last part of the whale to enter the water. The tail has two lobes, known as flukes, one at either corner of its wedge-shape. The back of the body of the whale is known as the dorsal surface and the underside of the body as the ventral surface. Correspondingly, the handle in one embodiment may have an arched or humped section and a wedge-shaped tail section at the end thereof. The tail end of the handle may also have two lobes or flukes, one located at either corner thereof.

The handle is ergonomic in the sense that it may fit a user's hand more naturally than an elongate dagger-type handle of the prior art. In particular, the fingers may slightly curl around and over the hump of the handle and the thumb may rest on the ventral or concave surface. With the hand in a natural relaxed position (in other words with the fingers in line with the forearm), the brush lies at an angle of approximately 45° from the notional axis of the forearm and fingers. This allows for a natural and relatively relaxed method of holding the brush such that in use both wrist and hand fatigue is avoided or postponed compared to the use of prior art brush handles. The thermoplastic elastomer covering, or forming, the handle may provide a surface which a user may readily grip comfortably without the possibility of the handle slipping relative to the fingers. Further, its resilience is more comfortable to hold than a solid incompressible surface.

In use, if a handle according to the invention is held such that the user's forearm is held out in front perpendicular to the user's body, with the hand orientated such that the forefinger and thumb are towards the shoulder of the user and the other fingers are aligned with the forefinger such that the little finger is towards the feet of the user, and with the forefinger approximately in line with the forearm, the handle, and thus a brush connected to it, will be orientated approximately 45 degrees away from the line of the forearm in the direction of the user's feet. This provides a natural orientation which is useful and ergonomically comfortable for painting something directly in front of the user at approximately the same level as the waist. The brush may be moved back and forth across and in front of the user's torso by rotation of the forearm relative to the upper arm, or by rotation of the

wrist, to provide even brush strokes and thus apply paint in the well understood preferred manner. Further, with the handle held in this position the brush may be orientated in a variety of directions in front of the user's torso merely by rotation of the wrist.

By contrast, a user adopting the same position as described above would hold a paint brush having a dagger-type handle with the fingers curled underneath to support the handle and the thumb gripping the opposite surface. The brush would then be pointing directly away from the user's torso approximately transverse to the upper arm and torso. In this position it is difficult to orientate the handle and thus the brush such that paint may be applied to a surface in front of the user's torso and at a position between the feet and the forearm of the user. Rather, the user would have to either raise the upper arm to shoulder level in order to rotate the forearm such that the brush may be pointed towards the feet and thus apply paint to the surface or would have to change the position of the handle relative to the hand.

A dagger-type handle of the prior art allows for it to be held in many different orientation with respect to the hand. By contrast, the handle of at least some embodiments of the present invention may only comfortably fit into the hand in one optimal orientation with respect to the hand. In other words the handle is prescriptive in nature with respect to the way it is held by a user. This orientation involves the fingers of the hand being kept substantially straight at least to the extent that they are not fully curled as is often the case with so-called dagger type handles. Keeping the fingers straight is known to allow a handle to be held and

used for longer periods, than compared with a handle being tightly gripped by the fingers, before cramp or other fatigue occurs.

According to a further aspect of the present invention there is provided an ergonomic paint brush handle, the handle having an elongate body for receiving a brush at one end thereof, whereby the brush lies in a notional brush plane, the body having a median plane lying along the length thereof and transverse to the brush plane, wherein the body is curved in the median plane, and the end portion of the handle, remote from that end of the handle which is arranged to receive said brush, being enlarged relative to a central waist portion of the handle and shaped to lie against the rear of either hand, between the thumb and forefinger, when in use.

According to a further aspect of the present invention there is provided an ergonomic paint brush handle, the handle having an elongate body for receiving a brush at one end thereof, whereby the brush lies in a notional brush plane, the body having a median plane lying along the length thereof and transverse to the brush plane, wherein the body is curved in the median plane, the body comprising a waist portion between its two ends for accommodating between the thumb and forefinger of either hand, and having a substantially fan-tailed end portion remote from the end arranged to receive said brush.

US 6,742,213 discloses a handle for a paint brush which has a "dog-leg" or step along its length such that the majority of the length is not coplanar with the brush head. However, the handle axis remains substantially parallel to the brush plane

but at an offset distance. Such a brush handle is known in the art as a "cutting-in" brush handle.

According to a further aspect of the present invention there is provided an ergonomic paint brush handle comprising: a head section for receiving a brush bristle cluster and oriented along a brush plane; and a handle section oriented along a handle plane the brush plane and the handle plane being substantially parallel to each other and offset from each other; in which the head section comprises a thumb rest portion on a dorsal side and a finger rest portion on a ventral side.

The thumb and finger rest portions allow the handle to be held comfortably between the thumb and one ore more fingers in the brush and handle planes. In other words the thumb and fmger/s extend generally parallel to the planes and coaxially with notional brush head and handle axes.

The thumb rest may comprise a raised surface, for example a disc-shape projection.

The finger rest portion may comprise an inclined step. The step may be inclined away from the brush head.

The finger rest and/or thumb rest may be positioned substantially opposite each other on the dorsal and ventral sides.

Further embodiments are disclosed in the dependent claims attached hereto.

Embodiments for the present invention will now be more particularly described, by way of example, and with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a handle for a paint brush according to the present invention;

Figure 2 is a side view of the handle of Figure 1;

Figure 3 is a plan view of the handle of Figure 1; Figure 4 is a perspective view of the handle of Figure 1 including two reference planes and an axis;

Figure 5 is a perspective view of the handle according to the present invention in use and being held in a left hand;

Figures 6 to 9 are a series of perspective views of the handle according to the present invention in use and being held in a right hand;

Figure 10 is a photograph of the brush of Figures 1 to 9 shown with the handle and brush head separated;

Figure 11 is a photograph of a perspective view of the brush handle shown in Figure 10; Figure 12 is a rear perspective view of the dorsal surface of the handle shown in Figure 11;

Figure 13 is a rear perspective view of the ventral surface of the handle shown in Figure 11 ;

Figure 14 is a cross-sectional view of a handle according to the present invention;

Figure 15 is a side elevation of a handle formed according to an alternative embodiment; Figure 16 is a side elevation of a handle formed according to a further embodiment;

Figure 17 is a side elevation of a handle formed according to an alternative aspect;

Figure 18 is a perspective view of a handle formed according to an altςrnative embodiment;

Figure 19 is a side elevation of the handle of Figure 18; Figure 20 is a plan view of the handle of Figure 18; Figure 21 is a side elevation of a handle according to an alternative embodiment; Figure 22 is a perspective view of the handle of Figure 21; and

Figure 23 is a side view of the handle of Figures 21 and 22 in use.

The handle 10 has an end for receiving a brush at one end thereof. A brush 15, typically comprising a bristle cluster, is attached to the handle at this end and held in place by means of a metal ferrule 20. The bristles are set into the ferrule 20 by a suitable adhesive, such as an epoxy, that extends into internal grooves formed by ribs in the wall of the ferrule 20. The ferrule 20 is connected to the handle 10 by a groove formed by a rib in the ferrule 20 and also by fasteners, which may comprise nails or rivets 21.

The handle 10 has an upper or dorsal surface 50 and a lower or ventral surface 60. The upper surface 50 has a hump 40 and is continuously curved from the end for receiving the brush head to a tail portion 30 comprising two flukes 30a, 30b at the opposite end. The upper surface curve is convex in form. By contrast, the lower surface 60 has a continuously curved surface which is concave in form. The handle 10 has a width (more readily seen in Figure 3) which varies along the longitudinal length of the handle such that there is a waist portion 70 approximately midway between the end for receiving the brush head at one end and the tail portion 30 at the other end.

Figure 2 shows more clearly the dorsal or upper surface 50 and the hump 40. Further, the ventral or lower surface 60 is more clearly seen to be curved concavely. The thickness of the handle is seen to taper towards the tail end 30.

The plan view of the handle in Figure 3 more clearly shows the width of the handle varying along its longitudinal length such that the end for receiving a brush head is approximately the same width as the tail end 30. However, between these two portions the width is reduced to a waist portion 70.

To better understand the shape of the handle 10, Figure 4 has been annotated to include a brush plane 85, a median plane 80 and an axis 95. Further, a line of intersection of the median plane 80 with the handle is indicated by a broken line 90.

It may be seen that the brush 15 lies in the brush plane 85. Further, it may be seen that the handle 15 is curved out of the brush plane 85 but so that it is curved in the median plane 80.

The upper surface 40 and lower surface 60 are curved, as described above, about an approximate centre of curvature as indicated by axis 95. There may in fact be one axis or centre of curvature for the upper surface and a separate axis or centre of curvature (not shown) for the lower surface 60, in which case the two axes would be parallel but not necessarily co-incident.

The handle is shown continuously curved in the median plane. Further, it may be seen that the first major surface or upper surface 40 is convex in the median plane whereas the second major surface or lower surface 60 is concave in the median plane.

With regard to the width of the handle body this is a dimension measured parallel to the brush plane 85. Conversely, the thickness of the handle body is measured in the median plane.

Referring to Figures 5 to 9 it is seen that when a user holds the handle 10 the fingers of the hand may fit comfortably over the arch or hump 40. Further, the thumb may rest in the lower or ventral concave surface 60. Between the fingers and thumb the handle 10 is gripped effectively.

With regard to the waist portion 70 this fits comfortably in the hand at the junction of the forefinger and thumb (this is particularly clear in Figures 5, 6, 7 and 9), such that the curvature of the waist portion of the handle closely follows the natural curvature of the side of the human hand between forefinger and thumb in a direction towards the wrist from the forefinger. Accordingly, with the handle and user's hand in one orientation as shown in Figures 5 and 6 part of the weight of the handle 10 is supported by this portion of the user's hand. This means that the remaining weight of the handle and brush is supported by the fingers and thumb. However, this weight is less than if the fingers and thumb had to support the entire weight of the brush and handle.

With the handle and user's hand in the orientation shown in Figure 7 the thumb acts as a pivot point with the brush-end of the handle being gripped by the fingers and the waist portion 70 and tail end 30 balancing the weight of the brush by being held in position by the side of the hand at the junction of the forefinger and thumb. The tail end 30 of the handle is often in contact with the back of the user's hand immediately behind the junction of the forefinger and thumb. To improve the comfort of this contact the tail end 30 has rounded corners, lobes or "flukes".

As is shown in the Figures the brush may be held in many different orientations and yet still be adequately gripped by the hand without fear of it slipping from the hand. The thumb and forefinger together grip the handle in a stable position such that the wrist is used to move the brush relative to the user's arm, hand fatigue is avoided, and the use of the handle and brush can be carefully controlled.

It should be noted that the ambidextrous nature of the handle in demonstrated in the Figures since in Figure 5 it is held by a left hand and in Figures 6 to 9 it is held by a right hand.

The shape and symmetry of the handle encourages a prescriptive grip for the user which is the same for both left- and right-handed painters.

The photograph of Figure 10 shows a handle according to one embodiment of the handle with a brush head by its side. The brush 15 is fitted to the handle 10 by means of the ferrule 20 interconnecting with a brush head receiving section 26.

Figures 11 to 13 are photographs illustrating the curvatures of the handle 10.

In Figure 14 a cross-sectional view of a handle is shown. Within the handle 10 is a solid core 24. It is seen that this core extends from the brush head receiving section 26 along the longitudinal length of the handle 10 but stops before it reaches the tail portion 30. This enables the majority of the handle 10 to be firmly gripped but allows the tail portion 30 to remain flexible as discussed above. The material covering the inner solid core 24 may be a thermoplastic elastomer.

Figure 15 shows a side view of a different embodiment of a handle 110 having one major surface 150 curved but having the other opposite major surface 160 planar in the same plane as the brush head 115. The curved surface 150 has a hump 140 in

the same manner as the previously discussed embodiment and hence the curve is convex in form and in the median plane.

Figure 16 shows a side view of another embodiment of a handle 210 having one major surface 250 planar in the same plane as the brush head 215 but having the other opposite major surface 260 curved. The curved surface 260 is concave in the median plane.

Figure 17 shows a side view of a handle 310 formed according to an alternative aspect. The handle 310 has two major surfaces 350, 360, both of which are curved in the median plane.

The handle comprises a head section 311 which receives a brush bristle cluster 315 and is oriented along a brush plane X. The handle 310 further comprises an interface section 345 which joins the head section 311 to an elongate handle section 312 oriented along a handle plane Y. The brushhead plane X and the handle plane Y are substantially parallel to each other but are offset from each other.

A ventral side surface 350 of the head section 311 comprises a hump 340 adjacent the point of connection of the head portion to a ferrule 320. The dorsal side surface 360 of the head section 311 comprises a shallow concave portion 366.

The ventral surface 350 also comprises a shallow concave portion 345 at the interface section 345 between the head section and the handle section. Similarly, the dorsal side surface 360 comprises a shallow hump or convex portion 365 at the interface between the head section and the handle section.

Referring now to Figures 18 to 20, there is shown a handle 410 formed according to an alternative embodiment. The handle 410 is generally the same as the handle 310 shown in Figure 17 in that it comprises a head section 411 and a handle section 412 which are offset from each other, as shown best in Figure 19.

The ventral side 450 comprises a head portion with a hump 440 and a concave portion 445 extending from the hump 440 to join the head portion to the elongate handle section, which in this embodiment is gently convexly curved. The curved interface portion 445 includes a plurality of ribs 446 which aid gripping of the handle 410.

The dorsal side 460 comprises a shallow concave portion 466 which is opposite the hump 440 of the ventral surface 450. The curvature of the concave portion 466 is less than the hump 440 and therefore the thickness of the head section 411 varies along its length. The concave portion 466 includes a raised disc 467. The hump 440 terminates with an inclined step 441.

The ventral surface of the handle section is generally straight. The dorsal side surface of the handle section is concave. The result is that the handle section

increases in thickness from the interface with the head portion to a maximum and then decreases towards the tail end of the handle.

Referring now to Figures 21 and 22 there is shown a handle 510 formed according to an alternative embodiment. The handle 510 is very similar to the handle 410 shown in Figures 18 to 20, In this embodiment the head portion is relatively wider than that shown in Figures 18 to 20.

Referring now also to Figure 23, the handle 510 is shown in use. The handle is gripped so that the fingers extend over the hump 540 and down the inclined step

541; the fingers come to rest over the hump and onto the ferrule 520. The thumb rests on the disc 567 so that it is opposite the fingers. The interface section 545 between the head section and the elongated handle section passes between the thumb and forefinger. The result is that the fingers and thumb of the user point generally forwardly and towards the brushhead i.e. generally along the planes of the handle.