Brush bar for a surface treating appliance

Abstract

The invention relates to a brush bar for a surface treating appliance, including a supporting body, at least one retaining member welded to the supporting body and at least one bristle tuft clamped in place on the supporting body by the retaining member. The use of welding to attach the retaining member to the supporting body allows for a reduction in the wall thickness of the supporting body, which is advantageous for locating a motor inside the brush bar.

1 . A brush bar comprising a supporting body and at least one bristle tuft, the bristle tuft being secured on the supporting body by a retaining member welded or surface-bonded to the supporting body, wherein the bristle tuft is either mechanically clamped in place between the retaining member and the supporting body or anchored in place by one or more intermediate anchor elements which are mechanically clamped between the retaining member and the supporting body. 
     
     
         2 . A brush bar according to  claim 1 , wherein the anchor element is welded to the bristle tuft. 
     
     
         3 . A brush bar according to  claim 1  or  2 , wherein the base of the bristles forming the bristle tuft are joined together to form the anchor element. 
     
     
         4 . A brush bar according to  claim 1 , wherein the bristle tuft comprises a plurality of pairs of bristles, each pair of bristles being formed by a single bristle filament looped underneath part of the intermediate anchor element or retaining member. 
     
     
         5 . A brush bar according to  claim 4 , wherein the intermediate anchor element is a locking pin. 
     
     
         6 . A brush bar according to  claim 1 , wherein the bristle tuft extends through one or more holes in the retaining member. 
     
     
         7 . A brush bar according to  claim 6 , wherein the retaining member is in the shape of a washer. 
     
     
         8 . A brush bar according to  claim 6  or  7 , wherein the retaining member forms a supporting collar around the bristle tuft for laterally supporting the bristles against excessive bending during normal use of the brush bar. 
     
     
         9 . A brush bar according to  claim 1 , wherein the retaining member and brush bar are formed from substantially the same material or from a weld compatible pair of materials. 
     
     
         10 . A method of manufacturing a brush bar having a supporting body and one or more bristle tufts secured on the support body, the method comprising: securing at least one bristle tuft by either clamping the bristle tuft in place between a retaining member and the supporting body or anchoring the bristle tuft in place using an intermediate anchor element which is clamped between a retaining member and the supporting body, and;
 welding or surface-bonding the retaining member to the supporting body.   
     
     
         11 . A method according to  claim 10 , wherein the retaining member is welded to the supporting body using ultrasonic welding. 
     
     
         12 . An apparatus for over-molding an anchor element or retaining member onto a bristle tuft, the apparatus comprising a centrifugal mold having one or more mold cavities which incorporate a radially-extending bristle-retaining portion for retaining a bundle of bristles, and an outer over-mold portion configured to conform to the nominal shape of the anchor element or retaining member. 
     
     
         13 . A method of over-molding an anchor element or retaining member onto a bristle tuft using the apparatus of  claim 12 , the method comprising placing a bundle of bristles in the bristle retaining portion of the mold cavity, subsequently injecting a thermoplastic resin into the mold cavity and either simultaneously and/or subsequently rotating the mold in order drive the thermoplastic resin into the over-mold portion of the cavity under centrifugal action.