Patent GB-108161-A (GB)
Title: Improvements in or relating to Machines for Sewing on Buttons.
IPC: D05B73/12
Filed: 1917-07-16
Abstract: 108,161. British United Shoe Machinery Co., (Assignees of Levegue, B. T.). July 17, L916, [Convention date]. Button-attaching machines; needle-shields.- Relates to sewing-machines for attaching buttons to boot or shoe uppers in which the button-attaching loops are anchored by the button. The workfeeding device is of the kind described in Specification 113,450 whereby forward movement of the work is avoided until the button has been properly secured. The invention comprises improvements. in the looper mechanism and in the mechanism for automatically presenting shanked buttons to the stitching-mechanism. The needle 26, Fig. 2, is carried by a hollow needle-bar 42 which is reciprocated in a block 50 by a cam-actuated lever. The block 50 is reciprocated to vibrate the needle and to move it during the feed of the work by a link 52 and a lever 60 which is mounted on a shaft 64 and is .connected by a spring and pin-and-slot connexion 78, 80 with a cam-actuated lever 62. The amount of feed is determined bv an adjustable block 68 which contacts with a block 76 carried by the lever 60. The thread take-up 30 is carried by a bell-crank lever 92 mounted at the end of a cam-actuated lever 88. The lever 92 is connected by a link 94 to the feed-lever 60 so that the take-up action is dependent on the feeding movement of the work. A A needle guard 54 is provided on the end of a spring-controlled bar 56 passing into a recess of the needle-carrying block 50. The looper mechanism is constructed to take a loop from the needle when it has passed through the worh and the eye of the button shank and hold it spread for the passage of a second needle-thread loop which is passed through the work outside the eye of the shank. The second loop is then seized by the loopers, spread, and passed over the head of the button and generally given up during its contraction. The devices for spreading the second loop are so arranged that the side of the loop leading to the to eye of the needle will lie substantially lengthways of the needle and so avoid bending the needle to any great extent. The loopers 28, Figs. 2 and 14, are adapted to overlie one another and are carried by concentric shafts 96, 98 mounted in a carrier 100. The shafts are oscillated in opposite directions by racks engaging pinions thereon. The racks are formed on a block 124 sliding in a guide-way on the carrier and actuated by a link 142 connecting it with the arm 140 of a rock-shaft 138 which passes through a hollow shaft 102 and is rocked by connexion with a cam on the cam-shaft. The carrier is secured to the shaft 102 which is rocked by connexion with another cam of the cam-shaft. As the second loop is being carried over the button-head, the latter is pushed through the loop by a part carried by the vibrating button shoot. The shoot is provided with a trunnion 184 secured in a bearing 186 and is vibrated by a link connecting it to the arm 190 of a rock-shaft 192 which is actuated by a cam on the cam-shaft. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the following subject-matter:- Button-attaching machines. -The shoot comprises an upper plate 154, Fig. 13 (cancelled), grooved to allow passage of the button shank and a back-plate 158 adjustably secured to the upper plate by slotted lugs. Two positioning-plates 156 are provided at the lower end of the shoot and a delivery hopper 202 with its delivery opening 204 in line with the button-passage at the upper end. The shoot is provided with a trunnion 184 secured in a bearing 186 by a clamp-nut carrying an arm 220, Fig. 2, with a segmental gear meshing with a pinion which is secured to the shaft of an agitating brush provided in the hopper. The shoot is vibrated by a link connecting it to th earm 190 of a rocksha.ft 192 which is actuated by a cam on the camshaft. A button-clamp 164 is mounted on a pin in the lower end of the backplate and is normally held out of clamping position by a spring and actuated by a arm 174 with a cam-surface engaging a fixed abutment to clamp the button. The button stop 162 is also mounted under spring control on the pin of the clamp and is adjustable for different dimensions of button. A supply hopper 224 is provided with a delivery opening leading into the hopper 202 out of line with the delivery opening 204 of the latter. Stopping and starting gear.-The cam-shaft 16, Figs. 7 (cancelled) and 9, is driven from a shaft 228 through gearing 230, 144 in the ratio of - :4. The shaft 228 has a fast pulley 232 and n, stop cam 234 formed with an eccentric braking surface and a recess adapted to take a stop 240 carried by an arm 242 on a rock-shaft 244 which is slidable under control of a spring 246. The stop is normally held in a position to engage the stop cam by a forked arm 248 secured to a shaft 250 which is actuated by a spring 252. The fast pulley 232 is adjacent to a loose pulley 236 mounted on a shaft 238 in line with the shaft 228. The belt is normally held on the loose pulley by a belt-shifter 254 which is carried by an arm 256 connected to the shaft 250 by a key and slot and a spring 260 which holds one end of the slot against the key. This arrangement is for the purpose of allowing the stop to be disengaged without shiiting the belt from the loose pulley when for any purpose it is desired to move the cam-shaft by hand. The belt-shifter is held stationary at such times by a latch 264 operable from the outside of the machine frame. The machine is started by moving the arm 248 by a link 272, bell-crank lever 274, and treadle-rod 276, and is maintained in action by a roller 278 on the bell-crank lever engaging a cam-surface on the cam-wheel 104. At the end of an operation, the roller drops into a recess in the cam surface and allows the stop-gear to come into action. This subject-matter does not appear in the Specification as accepted.