Patent GB-578213-A (GB)
Title: Improvements in trimming devices for round articles such as discs and buttons
IPC: B29D19/06
Filed: 1944-06-15
Abstract: 578,213. Grinding- machines. HORNFLOWA, Ltd., and NACHAZEL, V. June 15, 1944, No. 11468. [Class 60] [Also in Group XXII] A machine for trimming, by means of a grinding-wheel or cutting-tool, articles such as buttons and discs, comprises spring fingers serving to feed the blanks successively from a guide member to a rotating support, to permit a holding member to advance to press the blank on the support and then receding. to receive a fresh blank whilst the operating tool comes into action to trim the blank. The machine has a base 30, Fig. I, supporting a frame 32 with a cover 33 on .which is a hopper 35 containing the blanks which are fed by a rotating disc provided with a slot 37 to a feed shoot 38, with the recessed face of the blank downwards ; failure to deliver the blanks is indicated by the lighting of a lamp 50. The blanks fail between a stationary bracket 52, Fig. 8, and a guide member 53 pivoted at 54 and extended downwardly to straddle a rotating shaft 55 having its end 56 shaped to fit the moulded face of a blank. The arm 57 of the guide has secured at its lower end a tongue 60 pulled by a spring 61, Fig. 7, against, a stop 62, and allowing the member 53 to be pushed back during an actual trimming operation. The member 53 carries a slide 63 with forks 64 having pivoted thereto at 65 a plate 66 carrying a blade 68 with spring fingers 69 with bent-in ends for holding the blanks 70 as they fall ; the fingers are adjusted by a setscrew 71 and lateral fingers 72 direct the blanks to a central position. The plate 66 is pulled up. to the screw 71 by a spring 74. The slide 63 is raised and lowered by lever arms 78, carrying a screw 80 to limit downward movement and mounted on a shaft oscillated through a spring-returned link and lever by a cam on a vertical shaft 90 driven by the main shaft 45. The blank 70 is fed by the slide against the end of the shaft 55 where it is clamped by a member 95, after which the slide rises to carry the fingers 69 up ready to receive the next blank. The member 95 is carried by a screw 96 adjustable in the end of a lever 97 pivoted at 99 and movable through a link 104 and lever 105 by a cam on the shaft 90; the member 95 is advanced to operative position, as permitted, by the cam, by a spring. The lever 97 at its inner end carries an electric contact tongue which on the failure of the mechanism to deliver a blank to the shaft end 56, completes a circuit and lights the lamp 50 to,warn the operator. The grinding-disc 120, Fig. 15, is carried by an electric motor 121 adjustable on a table 123, which is pivoted, on ball bearings, on an adjustable axis 124, and is swung, to carry the periphery of the disc across the work, by a link 127 and lever 128 operated by a cam 131 against the action of a spring 125 ; as the table swings into operative position, the stop 62 swings the guide 53 &c. back about its pivot 54 to leave the space around the blank 70 clear for the grinding-disc. In a modification, the grinding-disc is mounted so as to be movable in a straight line ; in a further modification, Fig. 29, a cutting-tool 155 is used, carried by a saddle 154 movable on guides 153.