Patent GB-190717692-A (GB)
Title: Improvements in and relating to Buttonhole Stitching Machinery
Inventor: BROOKES ALFRED GEORGE
Filed: 1907-08-02
Granted: 1908-05-28
Abstract: 17,692. Brookes, A. G., [Reece Buttonhole Sewing Machine Co.]. Aug. 2. Buttonhole - sewing machines; double-loop stitchzng-machines; needle-bars, vibrating laterally; overedge - stitching machines ; needle - holders; needledriving. - Relates to buttonhole - sewing machines of the type described in Specification No. 22,856, A.D. 1892, and consists in the combination with the stitchforming mechanism including two loopers and two spreaders, of improved means for actuating the spreaders, and of a loop turner for the needle thread, mounted on the looper carrier. The needle-bar b<1>, Fig. 1, is driven from an eccentric which is actuated by toothed gearing from the main shaft a<2> and enters at its lower end a swivel block attached to a slide d<9>. A pin on the slide d<9> works in a diagonal groove in the zone-shaped projection of the revoluble casing d<14>, to which is secured the partial gear d<17> geared with a segment A<33> on a shaft A<32> ; to the lower end of this shaft is attached a segment A<7> to gear with the wheel 45 on the revoluble carrier 48, a projection from the segment being adjustably connected with a camactuated link B<1>; this cam controls the annular movement of the stitch-forming mechanism and actuates the cutter G<2x>. Another cam-actuated lever d<20> presses upon the zone-shaped projection to move the needle-bar laterally. The carrier 48 has a central shaft 59, Fig. 2, actuated from a cam 103 on the main shaft, this shaft having attached to its upper end a rod 108 to which is attached a lever 106 pivoted at 105 to the carrier, and having attached to its opposite end a link 113 which actuates a carrier block 116 pivoted at 117. The block has two arms, one carrying a thread-carrying looper 30 and a spreader 32, the other a non threadcarrying looper 31 and a spreader 33. The spreaders are normally held in inactive position by springs 34, 35. In order to actuate the spreaders, a separate member H is provided, pivoted at h<x> and actuated by a pin h' on the carrier bearing against one of the sides of the recess at its base, the member thus moving in a direction opposite the movement of the carrier. The actuating-member has two long bevelled arms h, h<1>, adapted to actuate the spreaders in turn when the block is tipped in one direction or the other. When a button-hole is to be commenced, the needle will be above the fabric, and at a distance from the edge of the slit equal to the required depth of stitch. It then descends through the work, and at the same time the spreader actuator is moved to the left, whereby the spreader 32 is actuated to spread the loop of under thread t<1> carried by the looper 30. The needle then passes through this loop, and the block 116 moves to the left, causing the looper to draw its thread round the needle, which then starts to rise and throws out a loop, which is entered by the looper 31 and spreader 33 and carried under the slit edge. The actuator H is then tipped to cause the spreader 33 to spread this loop so that the needle in its next descent passes through its own loop, having been moved laterally by the block d<9>, and in the final part of its descent draws the first loop tight, the looper 31 having backed out of the loop owing to the movement of the carrier 116 towards the right. As the needle rises it throws out a loop, which is entered by the looper 30 and the spreader 32, and the spreader moves to the left to actuate the spreader 32 to spread the loop under the edge of the fabric, so that the needle, in its next descent, having again been moved laterally, passes through the loop of looper thread and between this thread and the previous loop of needle thread. The block 116 is then again started towards the left, the spreader 32 is closed and with the looper retires from the loops, leaving a loop of looper thread about a loop of needle thread. The stitch formed is shown in Fig. 16. The central part of the block 116 is provided with a loop-turner n, Fig. 12, the two shoulders n<1>, n<2> of which serve to turn the loops of needle thread, that are thrown out opposite them into the path of the advancing loopers.