Patent GB-1190837-A (GB)
Title: Method and Apparatus for Segmenting Continuous Strip Material
Inventor: MCGILL THOMAS ALAN
IPC: B21D53/64
Filed: 1967-10-13
Abstract: 1,190,837. Breaking metal strip. GILLETTE CO. 13 Oct., 1967 [14 Oct., 1966 (2)], No. 46732/67. Heading B3E. A method of dividing into sections continuous strip material comprises separately reinforcing adjacent portions of the strip, holding one of the portions and moving the other portion transversely of the one portion, thereby breaking the strip between the adjacent portions. An apparatus for carrying out the method comprises a supply station 30 having an automatic tension-controlling brake; feed rollers 49; a loop-forming device which allows the strip to be drawn continuously from the station 30 and fed intermittently to the remainder of the apparatus; inspection stations 20 at which defective portions of the strip are identified and the information stored for the subsequent operation of a reject mechanism; a station 58 at which reinforcing tabs 16, 17, Fig. 2, are applied to the strip; a station 62 at which the presence of the tabs is confirmed and a station 120 at which the strip is divided into sections. Strip supply station 30, comprises a rotatable table 32 which supports a coil of strip razor steel 14, for use in a ribbon-type safety razor, with its sharpened edge 15 uppermost. The strip is drawn off continuously by feed rollers 49 and passes between a pair of rollers 36 carried by an arm 34. If the tension in the strip decreases the arm moves angularly due to a biasing spring and applies a brake to the reel. Loop forming device.-Strip leaving the rollers 49 is formed into a loop by an air jet 50, too small or too large a loop-size being detected by a limit switch 53 and photo-cells 52, respectively, which alter the speed of rolls 49. The rolls 54 are guide rolls which lead the strip past a block 56, the strip being held to the face of the block by a vacuum applied to one end of holes which pass through the block and open to the strip guiding face. The friction of the strip against the block creates tension in the strip passing through the succeeding stations. Inspection stations.-Information from the inspection stations 20 is stored in a mechanical memory cell and operates a reject shoot at the station 120, so that defective work is diverted to a reject bin. Tab applying station.-The metal tabs 16 and 17 are U-shaped and have an off-centre hole 18 in one side, the two types of tabs being supplied from separate feed bowls 60 and fastened to the strip by punches which move through the holes 18 and deform the strip 14 and the other part of the tab. There is a second vacuum tension block 57, similar to the block 56, at this station. Tab checking station, Fig. 6, comprises a channel 64 having a conductive wall 63 and opposite the wall 63 a transversely movable block 66 carrying a pair of electrodes 68, 70. The movement of the block 66 towards the wall 63 is limited to a position where it touches the tabs if present. The absence of a tab stops the apparatus. The last-attached pair of tabs are used to position the strip correctly for the succeeding pair of tabs, by means of a lever 72, having a nose which engages the trailing edge of the tab 16. The lever 72 is pivotally attached to a bell-crank 79 which is itself pivotally mounted on the frame. A pivoted arm 90 oscillates the bell-crank through a spring plunger 92, so that the nose of the lever 72 engages the tab and moves it if necessary. Strip breaking station.-Included in the breaking station is a transport mechanism comprising a pair of parallel chains 130 on which are mounted three spring-closed jaws 138. At each cycle of the apparatus the jaws 138 engage behind a tab 16 and move the strip forward until the following tab 17 is arrested by a pair of clamping jaws 142, Fig. 15. The jaws close on to, and hold the tab 17, a further pair of jaws 140, 141 close on to the tab 16 and the strip is then broken by transverse movement of the jaws 140, 141. The jaws 140, 141 are mounted on levers 151, 153, respectively, which are pivoted in scissor-fashion on a fixed bracket 152. The lever 151 is connected by a link 160 to a reciprocable rod 166 and the lever 153 has a pin- and-slot connection with a lever 162 also connected to the rod 166. Vertical downward movement of the rod first closes the jaws 140, 141 on to the tab 16 and then rocks the jaws about the pivot 154 to break the strip. As the leading section of strip is separated from the remainder it is gripped by a pair of spring-closed jaws 178, 180 mounted on a beam 182 which reciprocates vertically. As the beam moves upwardly the jaws 178, 180 are opened by camplates 190 which act against pins 192 projecting from the jaws. With the jaws gripping the strip the beam 182 is lowered to deposit the strip section between the teeth 173 of a pair of parallel combs, one of which is resilient to keep the strips under slight tension. The comb is mounted on a conveyer 176 which is moved in synchronism with the apparatus. If the mechanical memory cell signals that the part is a reject the beam 182 remains in its lower position and a reject tray (194), Fig. 20 (not shown), moves under the section. The rejected section is blown by an air jet along the tray to a reject shoot.