Method and apparatus to permit attachment of bristles to toothbrushes with resiliently flexible heads and to thereafter permit the trimming and end rounding of such bristles

A clamping apparatus to permit the trimming and end rounding, in an otherwise conventional finishing machine which includes at least one cutting tool and at least one end rounding device, of bristles attached to the head of a toothbrush comprising, a handle and a resiliently flexible head attached thereto, said head including a free tip end, said flexible head selected from the group consisting of angled heads, curved heads, segmented heads with joints connecting adjacent segments, and combinations thereof, said head having an upper surface and a bottom bristle-bearing surface, said clamping apparatus including means to hold said flexible head securely in at least a flattened configuration and to prevent buckling of said head while said tufts of bristles are trimmed or cut to a desired length and the free ends of said bristles are end rounded, said clamping apparatus comprising:

• a) a head engaging device capable of receiving heads of varying dimension, said device including a first means to releasably engage the tip of the free end of said brush head;
• b) rotating clamp means to releasably engage the portion of said brush head closest to said handle;
• and
• c) a spacing device of sufficient height to support the upper surface of said brush head to keep said bristle head in at least a flattened position.

A method of clamping the resiliently flexible head of an untufted toothbrush containing a plurality of bristle tuft-receiving holes in an otherwise conventional tufting machine having a tuft insertion tool that oscillates in a defined direction of travel in order to attach tufts of bristles to said head, said brush including a handle attached to said flexible head, said flexible head selected from the group consisting of angled heads, curved heads, segmented heads with joints connecting adjacent segments, and combinations thereof, said head having a front portion including a free tip end, a back end adjacent said handle, an upper surface and a bottom bristle-receiving surface, the method utilizing a clamping apparatus including means to hold said flexible head securely in a configuration in which said bristle-receiving holes lie substantially parallel to the direction of travel of said tuft insertion tool and to prevent the buckling of said flexible head while said tufts of bristles are inserted, said method comprising the steps of:

• a) conveying said brush to said clamping apparatus and deforming at least the flexible head of said brush until said flexible head is in a configuration such that said bristle-receiving holes lie substantially parallel to the direction of travel of said tuft insertion tool;
• b) bringing the tip of the free end of said brush head into abutment with a brush plate having an undercut area and auxiliary clamp means;
• c) firmly seating the upper surface of said brush head on a backing plate;
• and
• d) engaging the portion of said brush head closest to said handle with rotating clamp means until said head is immobilized such that said bristle-receiving holes lie substantially parallel to the direction of travel of said tuft insertion tool, whereby said tufting operation may commence.

A method of clamping the head of a toothbrush comprising a handle and a resiliently flexible head containing a plurality of bristle tufts, said head having an upper surface and a bottom bristle-bearing surface and a free tip end, said flexible head selected from the group consisting of angled heads, curved heads, segmented heads with joints connecting adjacent segments, and combinations thereof, in a conventional finishing machine in order to permit the trimming and end rounding in such conventional finishing machine, which includes at least one cutting tool and at least one end rounding device, the method utilizing a clamping apparatus including means to hold said flexible head of said toothbrush securely in at least a flattened configuration and to thereby prevent the buckling of said flexible head at a joint thereof while said tufts of bristles are trimmed or cut to a desired length and the free ends of said bristles are end rounded, said method comprising the steps of:

• a) bringing the tip of the free end of said brush head into abutment with a head engaging device capable of receiving heads of varying dimension;
• b) deforming said brush until said flexible head is in at least a flattened configuration;
• c) supporting the upper surface of said flexible head with a spacing device of sufficient height to keep said flexible head in at least a flattened position;
• and
• d) engaging the portion of said flexible head closest to said handle with rotating clamp means until said flattened head is immobilized, whereby said trimming and subsequent end rounding operations may commence.