GB680455A - Improvements in and relating to tooth brushes - Google Patents

Abstract

680,455. Toothbrushes. ENGEL, F. Oct. 19, 1950 [Nov. 25, 1949], No. 30265/49. Class 19. In a toothbrush of the type wherein a single folded tuft of bristles is attached to the end of a straight or preferably curved handle resembling a pointed and very stiff painter's brush the tuft of bristles is enclosed in a metal collar near its end where the bristles are doubled back upon themselves and is held firmly together with this collar within a restricted hollow portion at the end of a handle of thermoplastic material. The collar is preferably indented before insertion in the handle the collar being deformed to have a figure of eight cross section (Fig. 1) which may be restored by pressure to an approximately circular contour with two ribs of doubled material projecting inwards opposite one another (Fig. 2). In Fig. 3 the tuft of bristles 3 with metal collar 4 is inserted into the hollow end 2 of the handle 1 which may have been softened previously. Pressure may be applied by means of a clamping tool having semicircularly recessed jaws or by means of a die having a belled mouth 10 preferably rotated by means of a shaft 12. Preferably an inner head is formed to prevent the tuft slipping out by not compressing either the rear end of the bristles or the metal collar or both of these. The handle. may be curved or bent and may be tubular throughout. Preferably thermoplastic artificial resins are used for solid handles and celluloid is suitable for tubular handles. Fixing of the bristles may be aided by a cement. or acetone solution.