Patent GB-201997-A (GB)
Title: Improvements in boot and shoe stitching machines
IPC: D05B15/00
Filed: 1922-05-04
Abstract: 201,997. Pearson, W. May 4, 1922. Boot-sole sewing-machines; driving; waxing thread; rotary horns.-Machines of the McKay type are provided with means for simultaneously regulating the stroke of the needle-bar and the length of feed. The usual horn 20, Fig. 1, is revolubly mounted in a bracket 15 on the machine column, the whirl being actuated through shafts 25, 29, 33 and gearing from a cam-disc 47x, Fig. 2. The thread t is led through the shaft 25, an electrically-heated wax-pot 23, and a tension-device to the whirl. In the casing 38, Fig. 8, is a revoluble sleeve 40, on which is slidably mounted a power-driven pulley 41. On a shaft 42 revolubly mounted in the sleeve 40 is fixed a hand-wheel 43, while to the inner end thereof is fixed the cam-disc 47<x>. Inclined teeth 41 on a boss 43<x> on the casing engage similar teeth on a treadle-oscillated collar 45 loosely mounted on the sleeve 40. Oscillation of the collar 45 operates the clutch to drive the shaft 42. Chain-stitching; presser-bars with periodic control; feed by devices engaging the upper surface of the work.-A link 57, Fig. 2, is pivoted to a pin 56 on the disc 47<x> and to a rocker-lever 58, which is pivoted at 59 to an L-shaped lever 60 mounted on the casing. A link 62 connects the lever 58 to a collar 63 on the needle-bar 64. the hub 68, Fig. 3, of a lever 69 is loosely mounted on a stud 67, Fig. 2, fixed to the casing, and is link-connected to a collar 71 on the piesser-bar 72. Round a nut 73, which is adjustably mounted on the threaded hub 68, is adjustably clamped an arm 75, which is spring- connected to an arm 76<x>, Fig. 3. loosely mounted on a shaft 77. The shaft 77 is mounted in a lever 78, Fig. 8, and oscillates in a slot in the casing. The end 82, Fig. 6, of the lever 78 is universally link-connected to an arm 89 pivoted to the casing. A clock 91 on the arm 89 travels in a slotted link 93, which is pivoted at 94 to a lever 95. A shaft 96 on which the lever 95 is mounted is oscillated from the disc 47<x>. An arm 104 fixed to the shaft 77 carries a pivoted block 105. A screw 110 adjustable in a lug 109 of the arm 76<x> bears on a lug 111 of the arm 104. The lever 75 is limited in movement by a screw 112. Fig. 3. A plate 116 adjustably clamped to the lever 60 coacts with the block 105 to define the upward movement of the needle-bar. A block 123 pivoted in an arm 122 adjustably clamped to the stud 67 coacts with the lever 60 to define the downward movement of the needle-bar. The needle-bar is grooved at 141, Fig. 6, to receive a spring-pressed stripper-bar 142, the upper end of which has a lost-motion connection with a member 145, Fig. 2, which, together with the needle-bar, passes through a cast-off block 146. In a block 153 on the presser-bar is slidingly pivoted a feed-lever 156, Fig. 6. spring-connected to an extension 103 of the link 93. The block 153 has an extension 161 in which is mounted the presser-foot 162. To the block 153 are secured cam-plates 164 each having a slot 165 through which passes a pin 166 on the feed-lever. A link 167 connects the pin 166 and the member 103. A lever 170, Fig. 2, mounted on the threaded hub 68, Fig. 3, is oscillated from the cam-disc 47<x>, to engage the nut 73 and raise the presser-bar. The descent of the presser-bar does not actuate the nut 73. The end 174 of the arm 104 bears on the block 153, and helps to lock the lever 170 to the nut 73. Adjustment of the member 89 simultaneously alters the feed and the position of the block 105, thus altering the needle-bar stroke.