EP1551565B1

EP1551565B1 - Paint roller frame

Info

Publication number: EP1551565B1
Application number: EP03765421A
Authority: EP
Inventors: Hakan Johansson
Original assignee: Anza AB
Current assignee: Anza AB
Priority date: 2002-07-23
Filing date: 2003-07-22
Publication date: 2007-07-18
Anticipated expiration: 2023-07-22
Also published as: SE0202295L; NO20050953L; ATE367213T1; DK1551565T3; DE60315053D1; AU2003247314A1; SE525557C2; SE0202295D0; WO2004009250A1; EP1551565A1; NO337369B1

Abstract

The present invention refers to a paint roller comprising a frame (110) having a first part (112) formed to hold a handle and a second part (114) formed to hold a cylindrical tube with absorbent material. The frame (110) comprises, in an outer end (115) of its second part (114), one or several recesses (117) and one or several ribs (119). An outer bushing (130) can be arranged at said rib (119). The paint roller further comprises two roller end pieces (140, 150) arranged at said second part (114) and arranged to fix said cylindrical tube in the axial direction of the tube. Two bushings (120, 130) are arranged at said second part (114) and said roller end pieces (140, 150) are further mounted in bearings at said bushings (120, 130).

Description

Technical field of the invention

The present invention refers to a paint roller comprising a frame arranged to hold two roller end pieces, i.e. a wheel that retains a roller tube on the frame. More specifically, the invention refers to a roller comprising a frame having recesses and ribs and designed to hold a roller end piece arranged at or comprising a bushing, whereby said roller end piece is mounted in bearings at said bushing (see, for example, US 3,711,887 , corresponding to the preamble of either independent claim).

Background of the invention

The paint roller of the prior art has usually roller end pieces that directly abut against the frame of the roller. When the roller end pieces rotate around the frame, a mechanical wear will thus occur at the contact surface of roller end piece against the frame, due to the rotational friction between the roller end piece and the frame. A problem with the prior art paint roller, wherein the roller end piece of a plastic material rotates directly around a frame of metal is that certain types of paints, e.g. paints comprising chalk or certain types of filling material, may give rise to precipitation from the metal. This precipitation may in turn affect the quality and the tint of the paint. DE 196 32 319 A1 is an example of this type of arrangement.
The above-mentioned problem is especially common when the roller end piece is manufactured of a plastic material and the frame of e.g. galvanised iron or a stainless material.
The present invention solves the above-mentioned problem in that a roller end piece manufactured of a plastic-like material is arranged at or comprises a bushing which also is manufactured of a plastic-like material and which at mounting directly abut against the frame. Further, the roller end piece is mounted in bearings at the bushing, whereby the roller end piece can rotate around the frame. Thus, a bearing of the roller end piece where plastic wears against plastic is provided.
The above-mentioned US 3,711,887 describes a paint roller unit for attachment to a spindle of a paint roller frame, comprised of a thin core having the paint applicator material fixed about the outer surface thereof and a pair of molded end caps press-fitted within the respective ends of the core, each providing a reduced diameter female bearing sleeve for bearing engagement on a pair of spaced apart inner and outer bearing elements, press-fitted on the spindle, the inner bearing element being a collet bearing which holds the roller unit in a fixed longitudinal position on the spindle.
US 4,985,959 describes end support members mountable at each end of a paint-applying cover sleeve and adapted to receive the axle of a roller handle. Each support comprises a central hub which defines a chamber greater in diameter being the axle of a handle member. A radially expansible split tube is positioned in the chamber. When the axle is inserted into the split tube the latter expands radially outwardly and exerts a radially inward pressure on the axle to frictionally retain the axle in its logitudinally adjusted position.
Another drawback with the prior art paint rollers are the holding of the bushing at the frame. If the bushing is press-fitted at the frame, as is the case in e.g. US 3,711,887 , the bushing tends to come loose from the frame when for example a house-painter removes the roller tube in order to change to another roller tube. Since the painter often strikes the paint roller frame against an object in order to remove the roller tube from the paint roller, a great force is exerted on the outer bushing, which force the bushing cannot resist but is removed from the frame together with the roller tube.
The present invention as defined in claim 1 or 6 solves the fastening problem of the bushing by providing a frame comprising a first part formed to hold a handle and a second part formed to hold a cylindrical tube with absorbent material, wherein the frame in an outer end of its second part comprises one or several recesses and one or several ribs, and wherein an outer bushing can be arranged at said rib. The inventor of the present invention has discovered that by providing such a frame, the fastening of a bushing is increased approximately three times as compared with the fastening according to the paint roller of the prior art. This means that the force needed to remove the bushing from the inventive frame has to be approximately three times larger than the force needed to remove a bushing from a conventional paint roller.

Summary of the invention

Thus, the present invention provides a frame for a paint roller as well as a paint roller comprising such a frame as defined in independent claims 1 and 6 respectively. Further features of the invention are given in the dependent claims.
The paint roller comprises a frame having a first part designed to hold a handle and a second part designed to hold a cylindrical tube with absorbent material. Two roller end pieces are arranged at said second part and arranged to secure said cylindrical tube in the axial direction of the tube. Further, two bushings are arranged at said second part, whereby said roller end pieces are mounted in bearings at said bushings.
The frame comprises in an outer end of its second end one or several recesses and an outer bushing is arranged at said recesses by means of e.g. friction locking. Said recesses are further stamped and have an approximately oval cross section. An outer roller end piece is mounted in bearings at said outer bushing.
In an inner end of said second part, the frame comprises a lug. An inner bushing is arranged at said lug, which is arranged to restrict the axial movement of the inner bushing. The inner bushing can further be adjustably arranged at said lug.
Embodiments of the present invention are defined in detail in the accompanying claims.

Brief description of the drawings

An embodiment of the invention will be described in more detail below with reference to the accompanying drawings, in which

Fig. 1 schematically shows a cross sectional view of a paint roller according to the invention;
Fig. 2a schematically shows a plan view of an end piece according to the invention;
Fig. 2b schematically shows a cross sectional view of the end piece of Fig. 2a taken along the line A-A;
Fig. 3a schematically shows a side view of an inner bushing according to the invention;
Fig. 3b schematically shows a cross sectional view of the inner bushing of Fig. 3a taken along the line A-A;
Fig. 3c schematically shows an end view of the inner bushing of Fig. 3a seen from the inside;
Fig. 3d schematically shows a perspective view of the inner bushing of Fig. 3a;
Fig. 4a schematically shows an end view of an inner end piece according to the invention, seen from the inside;
Fig. 4b schematically shows a cross sectional view of the inner end piece of Fig. 4a taken along the line A-A;
Fig. 4c schematically shows a perspective view of the inner end piece of Fig. 4a;
Fig. 5a schematically shows a side view of an outer bushing according to the invention;
Fig. 5b schematically shows a cross sectional view of the outer bushing of Fig. 5a taken along the line A-A;
Fig. 5c schematically shows an end view of the outer bushing of Fig. 5a, seen from the inside;
Fig. 5d schematically shows a perspective view of the outer bushing of Fig. 5a;
Fig. 6a schematically shows an end view of an outer end piece according to the invention, seen from the inside;
Fig. 6b schematically shows a cross sectional view of the outer end piece of Fig. 6a taken along the line A-A;
Fig. 6c schematically shows a cross sectional view of the outer end piece of Fig. 6a taken along the line B-B;
Fig. 6d schematically shows a perspective view of the outer end piece of Fig. 6a; and
Fig. 6e schematically shows a side view of the outer end piece of Fig. 6a.

Detailed description of a preferred embodiment

The present invention thus provides a paint roller comprising a frame and a roller end piece, which roller end piece is arranged at the frame in a preferred manner by means of a bushing having a bearing function. An embodiment of the invention will be described in more detail with reference to the accompanying drawings, in which the same or corresponding components or functions are marked with the same reference numerals.
Fig. 1 shows a roller 100 comprising a frame 110 having a first part 112 designed to hold a handle (not shown). The roller 100 is thus held by a painter by means of the handle, which may have a more or less ergonomically elaborated design and may be equipped with a holding device etc as is common in the art. Further, the frame 110 has a second part 114 arranged to hold the roller tube itself (not shown), which roller tube has an absorbing surface for the application of paint during painting operations. The roller 100 further comprises in an outer end 115 of the second part 114, an outer end piece 150 which is mounted in bearings at an outer bushing 130, and in an inner end 116 of the second part 114, an inner end piece 140 which is mounted in bearings at an inner bushing 120. Further, the outer end piece 150 and the inner end piece 140 are arranged to fix the roller tube at the frame 110 and arranged to rotate around said bushings 120, 130 when e.g. the painter paints. As shown in the figure, the end pieces 140, 150 are approximately cup-shaped or cylindrically shaped and fitted at the frame 110 with the openings pointed towards each other.
An embodiment of a frame 110 according to the invention is shown in Figs. 2a and 2b. The frame 110 comprises in an outer end 115 of its second part 114, one or several recesses or grooves 117. These recesses 117 are pressed or stamped and have an approximately oval cross section. Further, the outer end 115 has at the recesses 117 a number of ribs 119. The recesses 117 and the ribs 119 are arranged to provide an improved fixation or fastening of an outer bushing at the outer end 115 of the second part 114. This fastening is provided in that the ribs 119 have an outer diameter that is larger than the inner diameter of the outer bushing, whereby the ribs 119, at assemblage, are arranged to engage the outer bushing. In Fig. 2b a cross section of a frame 110 along the line A-A in Fig. 2a is shown, whereby it is seen from the figure that the frame 110 has an approximately circular cross section and the recesses 117 has an approximately oval cross section. Further, the second part 114 has in its inner end 116 one or several knobs or lugs 118. These lugs 118 are arranged to restrict the axial position of the inner bushing 120 at the inner end 116 of the second part 114.
The bushings are in an embodiment of the invention manufactured of a plastic-like material or of a plastic material. For example, the bushings may be manufactured of a material comprising a polyamide or of a material comprising an acetal polymer. Further, the bushings are arranged at the inner or outer end of the second part of the frame by means of e.g. cold press-fitting, i.e. the bushings are pushed onto the frame without heating.
Preferably, the inner bushing is arranged in such a way at the inner end that its axial position may be adjusted. The outer bushing is preferably fastened at the outer end, whereby the outer bushing is kept in position by e.g. friction locking, i.e. by the friction obtained between the inner surface of the outer bushing and the frame.
As described above, the recesses are arranged to provide an improved fixation or fastening of the outer bushing at the outer end of the frame's second part, whereby an improved holding is achieved.
In Figs. 3a- 3d different views of an embodiment of an inner bushing 120 according to the invention are shown. As shown in the figures, the inner bushing 120 has the form of a cylinder having an approximately cylinder-shaped through hole. The through hole is defined by the inner surface 121 of the inner bushing 120. The inner bushing 120 has a first or inner part 126 and a second or outer part 127. The through hole is further arranged in such a way that its diameter in the inner part 126 is larger than its diameter in the outer part 127. After assemblage, the inner part 126 faces the centre of the second part 114 of the frame 110, i.e. the inner part 126 faces the outer bushing. The inner part 126 has at its end a shoulder 122 and the outer part 127 has at its end a flange 123. The shoulder 122 and the flange 123 are arranged to restrict the axial movement of the inner end piece, when the inner end piece is arranged at the bushing 120. Further, the inner part 126 of the inner bushing 120 comprises two tapered slots 124, which preferably are opposite each other. These slots 124 enable compression of the inner part 126 of the inner bushing 120 which simplifies the assemblage of the inner bushing 120 at an inner end piece. Preferably, the inner bushing 120 and the inner end piece are mounted before they are arranged at the frame 110. The inner bushing 120 is mounted at the frame 110 in such a way that the shoulder 122 is directed towards an outer bushing.
An embodiment of an inner end piece 140 according to the invention will be described further with reference to Figs. 4a - 4c. The inner end piece 140 is approximately cup-shaped or cylindrically shaped and has an open end side and a closed end side. The open end side, i.e. the side that after assemblage faces the outer bushing, is shown in a plan view in figure 4a. The inner end piece 140 has a whole envelope surface 141 around the circumference and a hub 142 for mounting on an inner bushing. A number of protrusions 143 are spaced around the circumference, which protrusions 143 have an approximately rectangular shape and extend over about half the axial length of the inner end piece 140. The protrusions 143 are aimed at providing a balanced friction between the roller tube and the envelope surface 141 of the inner end piece 140. Preferably, the protrusions 143 provides a friction locking of the roller tube, whereby the inner end piece 140 rotates when the roller tube rotates. Between the circumference and the hub 142, a number of spokes 144 extend in order to give the inner end piece 140 sufficient strength. Further, between the circumference and the hub 142, the spokes 144 may have a stabilising structure 145 in order to further increase the strength of the inner end piece 140. Further, the envelope surface 141 of the inner end piece 140 is elastic between the spokes 144. The inner end piece 140 further has in its outer end side a flange 146 arranged to restrict the axial movement of a mounted roller tube. Suitably, the number of protrusions are four and the number of spokes eight, but these number can of course be varied.
Figs. 5a - 5d show an embodiment of an outer bushing 130 according to the invention. As shown in the figures, the outer bushing 130 has the shape of a cylinder with a cylinder-shaped hole. This hole is preferably not a through hole. The cylindrical hole is defined by the inner surface 131 of the outer bushing 130. The outer bushing 130 has a first or inner part 136 and a second or outer part 137. The hole is further arranged in such a way that its diameter in the inner part 136 is larger than its diameter in the outer part 137. After assemblage, said inner part 136 faces the centre of the second part 114 of the frame 110, i.e. the inner part 136 faces the inner bushing. The end of the inner part 136 has a shoulder 132 and the end of the outer part 137 has a flange 133. The shoulder 132 and the flange 133 are arranged to restrict the axial movement of an outer end piece, when the outer end piece is arranged at the outer bushing 130. Further, the inner part 136 of the outer bushing 130 has two tapered slots 134, which preferably are opposite to each other. These slots 134 enable compression of the inner part 136 of the outer bushing 130, which simplifies mounting of the outer bushing 130 in an outer end piece. Preferably, the outer end piece and the outer bushing 130 are mounted before they are arranged at the frame 110. The outer bushing 130 is mounted at the frame 110 in such a way that the shoulder 132 is directed towards the inner bushing.
With reference to Figs. 6a - 6e an embodiment of an outer end piece 150 according to the invention will be described. The outer end piece 150 is approximately cup-shaped and has an open end side and a closed end side. The open end side, i.e. the side that after assemblage faces the inner bushing and the inner end piece, is shown in a plan view in figure 6a. The outer end piece 150 has a whole envelope surface 151 around the circumference and a hub 152 for mounting on an outer bushing. A number of protrusions 153 are spaced around the circumference, which protrusions 153 have a rounded tip shape and tapering off from its thickest point at the inner end side of the outer end piece towards the rounded tip. They extend over about half the axial length of the outer end piece 150. The protrusions 153 are aimed at providing a balanced friction between the roller tube and the envelope surface 151 of the outer end piece 150. Between the circumference and the hub 152, a number of spokes 154 extend in order to give the outer end piece 150 sufficient strength. The number of protrusions are suitably four and the total number of spokes are eight, but this number can of course be varied. Further, between the circumference and the hub 152, the spokes 154 may have a stabilising structure 155 in order to further increase the strength of the outer end piece 150. The envelope surface 151 is further arranged less elastic than the envelope surface of the inner end piece, whereby the fastening of a roller tube is greater at the outer end piece 150 than at the inner end piece.
In order to provide adequate holding and yet simple removing of the roller tube, the outer roller end piece 150 is also somewhat elastic. This is achieved in part by the material being elastic itself, and in part by the shape of the spokes. In particular, the spokes extending between the protrusions 153 and the hub 152 are somewhat elastic. This is obtained by the spokes having a tapering, i.e. these spokes do not support the whole way from the protrusions on the envelope surface to the hub. The outer part of the spokes can thus flex somewhat inwards, towards the hub. The intermediate spokes are not tapered and thus are relatively stiff.
The bushings and roller end pieces according to the invention are preferably manufactured of a plastic-like material. They are suitably adapted for use together with a roller tube which also is manufactured of a plastic-like material and also is somewhat elastic but they can also be used together with a roller tube manufactured of another material, e.g. cardboard.
Thus, the present invention provides a good bearing of the roller end pieces without risking deformation of or precipitation from the frame material. In conclusion, this is achieved by providing bushings having a bearing function between the frame and the end pieces, whereby the end pieces are arranged to rotate around the bushings instead of directly rotate around the frame.
The present invention has been described above with reference to an embodiment, but it should be understood that details of the invention can be modified without departing from the scope of the present invention. For example, the roller end pieces can be arranged at or integrated with a roller tube, whereby the roller tube with the end pieces are arranged at the bushings at the frame. Thus, the present invention is only delimited by the claims below.

Claims

A frame 110 for a paint roller (100) comprising two roller end pieces (140, 150) and two bushings (120, 130), namely an inner (120) and an outer (230) bushing said frame (110) comprising a first part (112) formed to hold a handle and a second part (114) formed to hold a cylindrical tube with absorbent material, characterised in that said frame (110) in an outer end (115) of its second part (114) comprises one or several recesses (117), one or several ribs (119), and in that the rib or ribs (119) have an outer diameter that is larger than the inner diameter of the outer bushing (130) adapted to be fitted to said outer end (115) of the frame (110), whereby the ribs (119), at assemblage, are arranged to engage the inner surface of the outer bushing (130).
A frame according to of claim 1, characterised in that said recesses (117) are stamped and have an approximately oval cross section.
A frame according to claim 1 or 2, characterised in that said outer bushing (130) of the paint roller (100) can be securely arranged at said rib (119) by means of friction locking.
A frame according to any of claims 1 - 3, characterised in that a lug (118) is arranged at an inner end (116) of said second part (114) and that an inner bushing (120) of the paint roller (100) can be arranged at said lug (118), whereby said lug (118) is arranged to restrict the axial movement of said inner bushing (120).
A frame according to of claim 4, characterised in that said inner bushing (120) is adjustably arranged at said lug (118).
A paint roller (100) comprising a frame (110) having a first part (112) formed to hold a handle and a second part (114) formed to hold a cylindrical tube with absorbent material, two roller end pieces (140, 150) arranged at said second part (114) and arranged to fix said cylindrical tube in the axial direction of the tube, and two bushings (120, 130), namely an inner (120) and an outer (130) bushing arranged at said second part (114), wherein said roller end pieces (140, 150) are mounted in bearings at said bushings (120, 130), characterised in that said frame (110) at an outer end (115) of its second part (114) comprises, one or several recesses (117) and one or several ribs (119), and in that the rib or ribs (119) have an outer diameter that is larger than the inner diameter of the outer bushing (130), whereby the ribs (119) are arranged to engage the inner surface of the outer bushing (130) of the two bushings (120, 130).
A paint roller according to claim 6, characterised in that said recess (117) is stamped and has an approximately oval cross section.
A paint roller according to claim 6 or 7, characterised in that said outer bushing (130) is securely arranged at said rib (119) by means of friction locking.
A paint roller according to any of claims 6 to 8, characterised in that an outer roller end piece (150) is mounted in bearings at said outer bushing (130).
A paint roller according to any of claims 6 to 9, characterised in that a lug (118) is arranged at an inner end (116) of said second part (114) and that an inner bushing (120) is arranged at said lug (118), whereby said lug (118) is arranged to restrict the axial movement of said inner bushing (120).
A paint roller according to claim 10, characterised in that said inner bushing (120) is adjustably arranged at said lug (118).
A paint roller according to claim 5 or 6, characterised in that an inner roller end piece (140) is mounted in bearings at said inner bushing (120).
A paint roller according to any of claims 6 to 12, characterised in that the envelope surface (141, 151) of said roller end piece (140, 150) has a number of protrusions (143, 153) which are arranged to fix a roller tube by means of friction locking.
A paint roller according to claim 13, characterised in that said protrusions (143, 153) extend about half the length of the axial length of said roller end piece (140, 150).
A paint roller according to any of claims 6 to 14, characterised in that said bushing (120, 130) has a first part (126, 136) and a second part (127, 137), that said first part (126, 136) at its end has a shoulder (122, 132) and that said second part (127, 137) at its end has a flange (123, 133).
A paint roller according to claim 15, characterised in that said shoulder (122, 132) and said flange (123, 133) are arranged to restrict the axial movement of said end piece (140, 150).
A paint roller according to any of claims 6 to 16, characterised in that said bushing (120, 130) in a first part (126, 136) has two tapered slots (124, 134).
A paint roller according to any of claims 6 to 17, characterised in that said bushing (120, 130) comprises a hole, the diameter of which in a first part (126, 136) of the bushing (120, 130) is larger than the diameter in a second part (127, 137) of the bushing (120, 130).
A paint roller according to any of claims 6 to 18, characterised in that said roller end piece (140, 150) is cup-shaped and has a substantially cylindrical envelope surface (141, 151) and a hub (142, 152) for mounting on said bushing (120, 130).
A paint roller according to claim 19, characterised in that a number of stiffeners in the shape of spokes (144, 154) extend between said envelope surface (141, 151) and said hub (142, 152).
A paint roller according to any of claims 6 to 20, characterised in that said roller end piece (140, 150) and said bushing (120, 130) are manufactured of a plastic-like material.
A paint roller according to claim 21, characterised in that said plastic-like material comprises a polyamide.
A paint roller according to claim 21, characterised in that said plastic-like material comprises an acetal polymer.