A paintbrush and a method relating to assembly of a paintbrush

The present invention relates in a first aspect to a paintbrush comprising a handle member, a head member with bristles extending into a ferrule from a first end of said ferrule, and a connector member connecting said handle member to said head member and comprising a head connection part and a handle connection part, said head connection part extending into said ferrule from a second end of said ferrule, said handle connection part having a handle holding cavity taking up one end of said handle member.

One such prior art paintbrush comprises a cylindrical metal ferrule and a connector member in the form of a plastic ring. A first end of the ferrule takes up bristles, which are attached to the remaining part of the head member by means of glue. The plastic ring is positioned in the ferrule, abutting the inner surface of the latter. The plastic ring has a handle holding cavity in the form of a central opening, which is of course also positioned within the ferrule, and which takes up a handle member of the paintbrush. Between the bristles and the handle member a cavity is provided, which is typically filled with an adhesive. This conventional paintbrush is typically manufactured in the following way: The ferrule is positioned on a horizontal surface with one end opening facing upwards. A suitable amount of bristle hair is measured out and positioned manually or by means of a machine in the ferrule with the root of the hairs pointing downwards. One to three small plastic or wooden pieces are wedged downwards between the hairs, after which the hairs are pulled upwards. Because of an inherent slightly wedge-shaped cross section the hairs are thus secured in their final position in relation to the ferrule, i.e. extending from the upward end of the ferrule and being held by their roots positioned in the ferrule. The ferrule is flipped over, and a carefully measured amount of glue is poured into the ferrule. The glue slowly enters in between the hairs and hardens before running out of the ferrule, thus gluing the bristles to the ferrule. Then the wooden, rod-shaped handle member is inserted into the slightly conical plastic ring. The cavity above the bristles is filled with an

adhesive, and the plastic ring is pushed into the ferrule. The adhesive, which may be in the form of an expanding polymer, is allowed to harden, resulting in the finished paintbrush.

One problem of this prior art paintbrush is that paint (or another fluid to be applied by means of the paintbrush) or cleaning liquid, such as water, rather easily enters the interior of the ferrule between the plastic ring and the wooden handle member and thus into other cavities of the head member, e.g. between bristles and plastic ring. As is known, wood deforms over time and with varying surrounding conditions, and thus some space between the handle member and the plastic ring is often present. The liquid absorbed within the head member runs out when the painter starts to paint, causing nuisance and destroyed clothing. Another, perhaps more important problem of the entering liquid is that the handle end and/or other parts of the interior of the head member, such as wooden wedge elements, expand and break the ferrule when absorbing the liquid.

In professional paint jobs it is important that the handle member is able to absorb the sweat transpired from the palms of the painter. To solve this problem, wooden handles are incomparable. However, another important aspect is that the handle should not slip in the painter's hand during painting. Further, when painting straight lines, such as corners or the transition between wall and ceiling, the professional painter slowly rotates the paintbrush in his hand, perhaps about 360°. This demands a lot from the surface configuration of the handle. If the handle does not provide sufficient surface friction in the gripping area, the paintbrush slips, and the painted line is not satisfactorily straight.

To this end, wooden handles are not suitable because of low surface friction. In contrast, plastic handles coated with a layer of friction material, such as rubber, are very well-suited. However, plastic-and- rubber handles are very inferior regarding absorption of palm sweat. When using a plastic-and-rubber handle for longer time periods, the handle thus gets wet and slippery and is furthermore not very comfortable to use.

The object of the present invention is to solve or alleviate the above problems, and more specifically to provide a paintbrush, with which it is possible to combine a satisfactory grip with sweat-absorbing characteristics of the handle. In order to meet this object the paint brush according to the first aspect of the invention is characterized in that said handle connection part encloses said handle member from said second end of said ferrule up to a distance from said second end such as to form a grip suitable for a user to grip during a painting operation. The paintbrush according to the first aspect of the present invention makes it possible to combine the advantages of a wooden handle with those of a plastic-and-rubber handle. Thus, a wooden handle member (or a handle member manufactured from another sweat-absorbing material) may be applied, which is able to absorb the sweat transpired from the palms of the painter. In the resulting paintbrush the handle connection part encloses the handle member up to a distance from the end of this and thus at the same time forms a friction grip on the part of the handle member, which is typically gripped during a painting operation. With the paintbrush it is thus possible to provide a grip, the friction features of which are comparable with the prior art plastic-and-rubber handles. At the same time the handle member may be manufactured such as to absorb palm sweat transpired from the painter's hand.

The connection between the handle member and the head member of the paintbrush is furthermore improved because the handle connection part is adapted to enclose the handle member up to a distance from the end of the handle member. This extends the support area of the connector member in relation to the handle member, making the connection between handle member and the head member more stable with the accompanying advantages during manufacture and use. Since the handle connection part is adapted to enclose the handle member up to a distance from the end of the handle member, a seal is moreover provided, which prevents entrance of liquid up to a certain distance from the end of the handle member. Especially when being placed with the bristles and the head in a glass or jar for cleaning pur-

poses, liquid is thus less likely to enter the head of the paintbrush.

In a preferred embodiment of the paintbrush according to the first aspect of the invention said handle connection part comprises a friction material, such as rubber, which is suitable for gripping by hand, such as to form a friction grip for a user to grip during a painting operation. Preferably, said handle connection part and said head connection part are integrally formed from said friction material. This provides for improved manufacture and a more stable resultant paintbrush. Preferably, said friction material provides higher friction than the material of said handle, e.g. friction corresponding substantially to that of rubber. The friction should be considered in relation to the skin of a hand of a user.

In another preferred embodiment said head connection part comprises a cavity enclosed by an outer circumference of said head con- nection part, said outer circumference extending substantially parallel to and on an inner side of said ferrule. This provides a stable resultant paintbrush, which may be readily manufactured. Preferably, said cavity of said head connection part extends into a through-going bore of said connector member, said through-going bore entering said cavity of said handle connection part. This provides for the possibility of letting a handle member of the resulting paintbrush extend through the connector member to be secured to an interior of the paintbrush head, e.g. by means of an adhesive, thus leading to a stronger connection between handle member and head member. If said cavity of said head connection part is conical, tapering towards said handle connection part, glue or expandable polymer is allowed to surround the end of the handle member during manufacture in order to secure this to the head member of the resulting paintbrush. At the same time, a large part of the head of the resulting paintbrush is composed of the connector member. The friction material of the connector member is typically both lighter in weight and cheaper than the adhesive, thus making the resultant paintbrush lighter in weight and cheaper in manufacture. Further, the paintbrush is overall more environmentally friendly because glue is typically more polluting when incinerated than the material from which the connector member is

manufactured.

Said handle member is preferably made from wood. Preferably, said head part is circular in cross section - it may, however, be of any suitable shape, e.g. oval or rectangular. In a preferred embodiment said connector member at the transition between said head connection part and said handle connection part comprises a circumferentially extending projection, said projection covering said second end of said ferrule. This makes the paintbrush more ergonomic since the risk of cutting one's hand on the second end of the ferrule is removed, and also the appearance of the paintbrush is improved.

In another preferred embodiment said handle member extends through said connector member such as to project into an adhesive- filled cavity formed between said head connection part and said bristles. In another preferred embodiment said handle holding part is manufactured from a resilient material, inner dimensions of said first end of said handle holding cavity being smaller than outer dimensions of said handle member such as to provide fastening of said handle member in said handle holding cavity as well as sealing of said handle holding part against said handle member. During manufacture of the paintbrush, the handle member may thus be pushed or forced into the handle holding cavity, thereby fastening the handle member to the connector member. Since the dimensions of the cavity are smaller than those of the handle member, in the paintbrush the handle connection part is resiliently pressed against the handle member, thus providing an improved sealing effect. Further, in this way it is possible to apply a rubber grip to a wooden handle member in a very cost-effective way. As is known to the skilled person, it is normally not an option to cast rubber directly on wood. In a second aspect the invention provides a method for connecting a handle member of a paintbrush to a connector member of said paintbrush, comprising the steps of a) providing a connector member comprising a handle connection part with a handle holding cavity and a head connection part

adapted to be connected to a head member of said paintbrush, said handle connection part being manufactured from a resilient material, b) providing a handle member with a first end, the inner dimensions of said handle holding cavity being smaller than the outer dimen- sions of said first end of said handle member, and c) forcing said first end of said handle member into said handle holding cavity by means of said resiliency of said handle connection part.

The second aspect of the invention provides advantages similar to those described in the above in relation to the corresponding em- bodiments relating to the first aspect of the invention.

In a preferred embodiment of the method according to the second aspect of the invention said connector member is as laid out in any of the above embodiments according to the first aspect of the invention.

The invention will be explained in more detail in the following by means of examples of embodiments with reference to the schematic drawing, in which

Fig. 1 is a cross-sectional view of a paintbrush according to the first aspect of the invention,

Fig. 2 is an exploded cross-sectional view of the paintbrush ac- cording to Fig. 1,

Fig. 3 is a view of a connector member of the paintbrush of Fig. 1 seen in perspective,

Fig. 4 is a view of the connector member of the paintbrush of Fig. 1 seen in another perspective, Fig. 5 is a view of a second embodiment of a paintbrush connector member seen in perspective, and

Fig. 6 is a view of the paintbrush connector member according to Fig. 5 seen in another perspective.

In this specification any brush, which is suitable for applying a liquid to a surface falls within the expression "paintbrush". The liquid may, for example, be in the form of paint, wax, lacquer, water or any type of pretreating or aftertreating liquid, coatings and the like.

Throughout the drawings like reference signs refer to like elements or elements of the same function.

Fig. 1 is a cross sectional view of an embodiment of a paintbrush according to the first aspect of the present invention. Fig. 2 shows a similar view with a head member 2 and a wooden handle member 3 of the paintbrush separated from a connector member 1. Referring to both Fig. 1 and Fig. 2 the head member 2 is of circular cross section, when seen from the ends of the paintbrush, and consists of bristles 4 and a circular-cylindrical metal ferrule 5 with an interior cavity 6 filled with adhesive. In other embodiments the cavity 6 is not filled with adhesive, it may e.g. be left as an empty space, thus how- ever typically lowering the overall quality of the paintbrush. The bristles 4 extend into the ferrule 5 from a first or lower end of the ferrule. The bristles 4 are collected to a circular-cylindrical shape corresponding to that of the ferrule 5 and are connected to the remaining parts of the head member 2 by means of glue 7 provided at the top ends of the bris- ties 4. In the area of the glue 7 plastic or wooden pieces (not shown) are provided, cf. below.

The connector member 1 is shown in perspective and in more detail in Figs 3 and 4. The connector member 1 is integrally formed from a resilient friction material and comprises a head connection part 8 and a handle connection part 9 with a handle holding cavity 12. The head connection part 8 comprises a cavity 11 enclosed by an outer circumference of the head connection part 8. The head connection part 8 extends into the ferrule 5 from a second or upper end of the ferrule 5. The outer circumference extends substantially parallel to and on the inner side of the ferrule 5, this circumference however being slightly conical, tapering towards the bristles 4. The cavity 11 extends into a through-going bore 12a of the connector member 1 and enters the handle holding cavity 12. The cavity 11 is conical, tapering towards the through-going bore 12a, and the cavity 12 is circular-cylindrical. As can be seen from Fig. 1, the cavity 11 of the head connection part 8 and the interior cavity 6 (cf. also Fig. T) of the head member 2 are filled with an adhesive in the form of an expandable polymer 6a, which also extends on the slightly conical outer circumference of the head connection part 8 to fill up the space between the ferrule 5 and the

head connection part 8. Since the head connection part 8 thus has a large surface area surrounded by the expandable polymer 6a, the head connection part 8 is reliably secured in the expandable polymer 6a and thus to the remaining parts of the head member 2. The connection member 1 comprises a circumferentially extending projection 13, which is seen best in Fig. 4. As can be seen from Fig. 1 the projection 13 covers an upper edge of the ferrule 5.

Still referring to Fig. 1 the handle member 3 is rod-shaped, and one end portion 14 with a circumferentially lowered or depressed cross section extends through the cavity 12 of the handle connection part 9 and the through-going bore 12a of the connector member 1 into the cavity 11 of the head connection part 8. Here, the end portion 14 is attached in the expandable polymer 6a of the cavity. The attachment is improved by means of a circumferential cutout 15 of the handle member 3, which is located near the end of this.

The inner dimensions of the cavity 12 of the handle connection part 9 and the through-going bore 12a of the connector member 1 are slightly smaller than the outer dimensions of the end portion 14, the handle connection part 9 thus being resiliently pressed against the end portion 14. This provides fastening of the handle member 3 to the connector member 1 as well as sealing of the connector member 1 against the handle member 3.

The circumferentially lowered cross section of the end portion 14 makes the handle connection part 9 substantially flush with the han- die member 3 and thus provides a smooth, aesthetically appealing transition between these. This provides for a more ergonomic handle of the paintbrush, a user's hand not being disturbed by a sharp transition between the handle member 3 and the connector member 1. The handle connection part 9 completely covers the end portion 14 of the handle member 3 and thus provides a friction grip of the handle adapted for a user to grip during a painting operation. The friction material of the connector member 1 thus encloses the handle member 3 from the second end of the ferrule 5 up to a distance from the second end such as to form a friction grip adapted for a user to grip during a painting opera-

tion. The friction material is suitable for gripping by hand and may for example be rubber or any artificial rubber-like material with larger friction than wood.

Generally, the material of the connector member of the paint brush of the present invention preferably comprises one or more thermoplastics and/or one or more thermoset plastics and/or one or more elastomers. Most preferred, the connector member comprises or consists of a mixture of a thermoplastic and an elastomer, i.e. a TPE.

The diameter of the handle connection part 9 slightly increases in the direction away from the head member 2. This is in order to fit the shape of the handle member 3, which has a wider cross-section on the middle of its length in order to fit into a cavity of a user's clenched hand. This also makes introduction of the handle member 3 into the connector member 1 easier during manufacture of the paintbrush. As is conventional, the handle member 3 at its opposite end comprises a bore 16 in which the paintbrush can hang for example on a wall.

Figs 5 and 6 show a second embodiment of a connector member 1. The connector member of the above-described embodiment of the paintbrush according to the invention being of circular-cylindrical cross section suitable for painting e.g. corners, the connector member of the second embodiment has a more oblong cross section with rounded off ends and is thus suitable for painting larger surfaces. This second embodiment of a connector member 1 may be applied to a paintbrush ac- cording to the invention similarly to what was described in the above, the paintbrush however being provided with a more oblong distribution of the bristles 4.

The paintbrush and the connector member according to the first aspect of the invention may be designed in other ways than the above- mentioned embodiments within the scope of the present invention. Thus, the connector member need not be integrally formed. The parts may for example be manufactured individually and then glued or welded together. Other materials than rubber may be used for the connector member, these including a polymer of a suitable kind or an artificial rub-

ber material, perhaps provided with greater softness and/or friction and/or resilience by means of one or more additives. In order to improve friction the grip of the connector member may also comprise small indentations and/or projections or other kinds of friction-enhancing sur- face-modifications.

The paintbrush as described in connection to the first embodiment of the first aspect of the invention may be assembled by means of the method described in the following, this method being an embodiment of the method according to the second aspect of the present inven- tion.

Attachment of the bristles 4 to the ferrule follows the above- described method of manufacturing the conventional prior art paintbrush: The ferrule 5 is positioned on a horizontal surface with one end opening facing upwards. A suitable amount of bristle hair is positioned in the ferrule 5, and one to three small plastic or wooden pieces (preferably plastic) are wedged downwards between the hairs, after which the hairs are pulled upwards. The hairs are thus secured in their final position in relation to the ferrule 5. The ferrule is flipped over, and a carefully measured amount of glue 7 is poured into the ferrule 5. Then the end portion 14 of the handle member 3 is forced or pushed, e.g. by means of a suitable machine, into the handle holding cavity 12 and the through-going bore 12a of the connector member 1 by means of the resiliency of the friction material of the connector member 1 and the smaller dimensions of the handle connection cavity in relation to those of the end portion 14, thus securing the handle member 3 to the connector member 1. The connector member is preferably cast.

The cavity 6 above the bristles 4 is filled with the expandable polymer, and the head connection part 8 and the handle member 3 are pushed into the expandable polymer until the circumferential projection 13 of the connector member abuts the ferrule 5. The conical inner and outer shapes of the head connection part 8 ensure that the expandable polymer completely fills all empty spaces of the head member 2. Finally, the expandable polymer is allowed to harden.