Patent GB-705364-A (GB)
Title: A method of and apparatus for forming bristles into tufts for the production of brushes
IPC: A46D3/08
Filed: 1949-10-14
Abstract: 705,364. Method and apparatus for forming bristle tufts. MORTIMER, H. May 23, 1950 [Oct. 14, 1949], No. 26421/49. Class 19 A method of forming bristles into tufts for the production of brushes consists in arranging the bristles all parallel to one another within a box and end on to one face of the box which face has a series of apertures of a size and shape appropriate to that of the tufts to be formed, vibrating such box so that sets of bristles work down through said apertures to a predetermined distance for forming tufts, sealing the protruding bases of the tufts to hold together the bristles in each tuft and then withdrawing the tufts from the box. The bristles may be natural or artificial the invention being particularly applicable to artificial filaments, e.g. nylon, capable of being fused by heat, but the tuft bases may also be sealed by adhesive according to the type of bristle used. Fig. 1 shows the working position of the box loaded with filament or nylon F the loading being carried out with the aid of the ribbon or strip of silk 1 which stays in the box as long as it contains filament and enables any remaining filament to be withdrawn for re-loading. Fig. 2 shows the internal construction of the box and the mode of formation of the tufts. The extrusion apertures are provided in a former plate 12 which forms the upright front of the box when in the loading position. The front and back plates of the box when in the loading or vertical position are parallel whilst the sides of the box and the bottom can c¾mplete a rectangular box, or the sides may be inclined to form a "V" with a pointed or rounded. base. A stepping plate 2 is provided at an adjustable distance below the former plate so as to keep the ends of the tufts straight and at a proper distance from the former plate for fusing the ends. The box is hinged at 3 to a stand 3a to allow vibration on a stopping plate 5 and this may be done mechanically by a cam or by hand at the end 4 of the former plate. The box is first raised on its hinge so that the former plate is in a substantially vertical position and is then loaded with bristle or filament by means of the ribbon or strip of silk 1. A spring-pressed pressure plate 16 is then inserted into the box so as to rest on top of the filaments and the box closed by a lid 18 rigidly held in position. The box is then lowered into working position and 'is slightly bumped or vibrated on the stopping block 5 so as to extrude the filaments through the slots in the former plate. The slots may be of any desired shape in cross-section, e.g. as shown at 7, 8, 8a and 10 and may have a small rebate such as 14 to assist in forming a tuft base on sealing the ends of the filaments. When all the apertures have been filled the box is returned to the loading position, the stopping plate 2 removed, and the ends of the filaments sealed by fusion or by an adhesive which sets hard. Whilst the sealed end of the bristles is still molten or soft a small metal plug or wedge 9 may be inserted or in the case of rectangular slots such as 10 a wire reinforcement 20 may be inserted longitudinally in the base. The tuft bottom is then completely sealed over and when the seals have hardened the tufts are withdrawn for assembly into base plates or holders having holes corresponding to the shape of the tuft bases and the base plate is then assembled with a handle to form a brush which may be a shaving brush, paint brush, or stippling brush according to the shape and size of the slots in the former plate.