Patent GB-208240-A (GB)
Title: Improvements in or relating to punching processes and machines
IPC: C14B5/00
Filed: 1922-09-16
Abstract: 208,240. British United Shoe Machinery Co., (United Shoe Machinery Corporation). Sept. 16, 1922. Reciprocating punch machines; work-feeding arrangements. - In a punching-machine, particularly for boot uppers, in which the work is backed by paper, interposed between the work and the cutting-bed, and fed automatically to present different portions of the paper to the punching device, means are provided whereby the punch is reciprocated a number of times against the same portion of the backing strip. The punch-carrying sleeve 24, Fig. 1, slides with a vertical feed sleeve 22 mounted for front to rear reciporoation. The sleeve 24 has a horizontal channel 26 in which is guided a block 32 jointed to the lower end of a lever 34 pivoted on a pin 36 fixed on the frame. Between the upper end of the lever 34 and an ear 40 on a loose sleeve. on pin 36 is connected a link 42 actuated through lever 44 from a cam 48 on a shaft 50. The movement of the block 32 extends over the dead centre and causes the punch to have a slight retracting movement. The feed sleeve carries sleeves 60, 62, Fig. 3, sliding on fixed shafts 64, 66 and lugs 78, Fig. 1, pivoted to a link 80 jointed to a block 84 sliding in a channel formed on the site of a rock arm 86 fixed to a shaft 88. This latter carries an arm 90, connected by a link 92 to an arm 94 pivoted on a pin 96 and actuated by a cam 98 on the shaft 50. The cam 98 actuates the feed sleeve while, the punch is stationary. The work feeding stroke is adjusted without altering the initial position of the punch by moving the block 84 in the rock arm channel..The block 84 is connected by a link 102 to an actuating handle 106 and a graduated indicator 110. Paper backing strip is fed from a filctionally held reel 218, between the punch and punch block to a reel 226 driven through a friction clutch and worm gearing 236, 234 from the main cam shaft. The punch after piercing the stock retracts in order to clear the backing strip before feeding; this movement is periodically neutralized by raising the punch block and the backing strip during the punch feeding movement. An anvil 250, Fig. 11, slides within a guide plate 256 and supports a punch plate 264. A slotted clamp plate 266 is secured to cheeks on the guide plate 256. The anvil has an elongated slot 274 engaged by a pin 272 passing through cheeks and engaged by an arm 276 secured to a hub 278 loose on a rock shaft 280 journaled to the anvil and carrying an arm 284 interposed between stop screws 292 in the hub 278. There is thus a yielding connection between the rock shaft 280 and the hub 278 and the punch plate 264 can be yieldingly raised. On the other end of the rock shaft 280 is a spring pressed arm 294 carrying a pin 296 supporting a roller 298 which can be manually moved to engage any one of three cams 300, 302, 304 bearing different numbers of humps. The punch plate 264 normally rests upon the anvil 250, and a ledge 262 of guide plate 256 is below the punch plate. When any cam oscillates the arm 294, plates 256, 266 are raised and the backing strip is first released for feeding movement and then raised to keep the punch embedded in the strip. The anvil has hand-operated vertical wedge adjustment in a casting 324. This latter together with the punch plate, and work-plate have horizontal adjustment in a shelf 330 on the frame, this adjustment moving the backing strip widthwise. Punches, construction and mounting of.-The punches may be arranged in a block 122, around a master punch 120, detachably fixed by a clamp screw in a head 126 from which projects a swivelling punch spindle. The punch spindle has a spring pressed central stop 134. Work-clamping arrangements. - A resiliently mounted presser foot bar 144, Fig. 10 guided hy a block 156 sliding in a groove in the frame, engages a split sleeve 146 with a horizontal rib on which slides a block 148, fixed by a screw 150, terminating in a hold down 152. A second adjustable hold down 154 has an extension sliding in the block 148. The bar 144 is reciprocated alternately with the punch by a roller 158, Fig. 1, actuated by a cam 160 on lever 34, but can be lifted from a treadle, connected by a rod 168 and lever 164 to a pin 162. Work-gauging arrangements.-A gauge arm is adjustably mounted in a bracket 180, and carries an edge gauge 206 mounted on a shank which is out of the vertical and is held down by spring pressure to the work support. A presser foot 210 in the form of a leaf spring is attached to the gauge arm. Specification 22884/04 is referred to.