Patent GB-415759-A (GB)
Title: Improvements in or relating to apparatus for operating upon sheet material
IPC: B26D1/00
Filed: 1933-01-31
Abstract: 415,759. Cutting and severing machines for sheet rubber and the like. BRITISH UNITED SHOE MACHINERY CO., Ltd., Union Works, Belgrave Road, Leicester.-(United Shoe Machinery Corporation ; 140, Federal Street, Boston, U.S.A.) Jan. 31, 1933, No. 2942. [Class 31 (i).] In apparatus for cutting out blanks, such as shoe soles, from flexible sheet material, particularly sheet rubber, the cutting tool is moved in a pattern-controlled path and the material is fed from a supply reel by means involving a spare of the sheet material, the length of which governs the feed. A belt supports the sheet material during the cutting-out operation, and is penetrated by the tool. The belt receives a step-by-step feed, the length being adjustable to the work required. The work piece may be embossed or marked during the halt for the cutting operation. The sheet material M, Fig. 1, is drawn from a reel 40 and forms a loop r before proceeding to the feed roll 110, embossing mechanism C, Fig. 2, and cutting mechanism D. The sheet stock on the supply reel, if of freshly calendered rubber or the like, has its convolutions maintained out of contact by separating means such a series of transverse slats L extending between spaced sprocket chains. A web of textile material l may also be wound in with the sheet rubber stock. The separator is drawn off the reel with the material M, and after leaving it, is wound on a reel 60. The material l also parts company from the sheet stock and is wound on a core 78. Means are described for facilitating the withdrawal of the reel 60 and the core 78. The loop r shown in Fig. 1 is of sufficient length not to operate the feed mechanism until the cutting mechanism has used up sufficient of the material to shorten the loop, which thereupon engages a roller 94 carried by an arm 96, pivoted on a shaft 98 carrying a short arm 100 for engaging a rod 102 and thereby actuating a friction clutch. The clutch transmits motion from a motor 50 through reduction gearing 56 and sprocket gearing 58 to a shaft 48. The shaft 48, through a chain of gears 46, operates a sprocket wheel 42 driving a chain 41 of the separator L, and lengthening the loop r to release the clutch. Feeding mechanism B shown in Fig. 2 involves a feed roller 110, and a guide roller 112, which latter increases the peripheral engagement of the stock R with the feed roller. The guide roller has a pair of adjustable flanges for different widths of stock. The stock R passes along a table 118, and is embossed at C before passing on to a supporting belt 120 of rag stock or other soft penetrable material which supports the work during the cutting operation. The cutting-knife K, Fig. 20, is mounted in a holder 403 bearing against the pattern P, and is mounted on a vertical extension 444 attached to a pivoted carrier-arm having a part 414, Fig. 18, united by a link 416 to an arm 418, oscillating about a stud 420. The carrier arm is constantly revolving about the pattern during an operation, and its pivot is caused to follow a curve such as b through the action of an eccentric 374, crank 376, and a disc free to turn about an extremity of a pin 380, and rotated by a pinion fast on it and meshing with an idle pinion 390 journalled on a stud depending from the eccentric strap 378. The cutting force applied to the knife is therefore in such a direction generally tangentially to the pattern curve that the cut will be made smoothly. During a part of each double revolution of the carrier-arm, the point of the knife, which is inclined at the angle of the lower inclined pattern surface, is held above the lower face of the pattern by a spring and cam release action. A pressure device Q lifts the feed belt 120 with the work and clamps it against the lower face of the pattern. The knife holder contacts with the periphery of the pattern, a spring yields, and the holder and knife ride down the pattern-surface and the knife travels through the work, slightly penetrating the belt to ensure complete severance of the sole. This continues for somewhat more than a revolution of the knife about the pattern. After the sole is cut, a cam causes the knife carrier-arm to swing, allowing a spring to elevate the knife point above the lower face of the pattern. Thereupon the pressure device Q falls carrying the belt 120 and the stock, the knife thereby being prevented from mutilating the sole area. Different patterns are used for cutting an " outside-bevel " sole to give a straight edge and for cutting an inside bevel the knife holders being also changed. The knife may be electrically heated.