GB448499A - Improvements in or relating to heel attaching machines - Google Patents

Abstract

448,499. Boot - making machines. UNITED SHOE MACHINERY CORPORATION, 140, Federal Street, Boston, U.S.A.- (Assignees of Standish, J. F. ; Winthrop, Massachusetts, U.S.A.) Nov. 8, 1934, No. 32097. Convention date, Nov. 13, 1933. [Class 17 (i)] Heels, machines for.- Relates to heel-attaching machines of the kind having a fluidcontaining cylindei with a tubular piston which can be closed by a valve interposed between work clamping means and operating means therefor, and consists in mounting the valve so that it is stationary during the normal working of the machine, but adjustably so that the extent of clamping movement may be varied. The clamping of the heel is by power and the clamp is moved a predetermined distance after engagement with the work, independent of the height of the heel. The clamping means comprises tread and rear abutments 48 carried by a slide 42 guided for vertical movement in the machine column 10 and normally urged to its uppermost position by a lever 52 biassed by a spring 50. The slide carries a cylinder 74 containing oil, within which cylinder is a tubular piston 76 depending from a slide 78 also guided for vertical movement and urged upwardly by a spring 86, the slide 78 having an extension 82 below the drive shaft 24 of the machine, with a roll 90 engaging a cam 92 on the shaft. A bridge bar 100 fixed to the machine frame has secured thereto a plate 104 retaining a nut 102 which can be turned by a handle 108, through an angle limited by stops, a spring detent 110 holding the nut in adjusted position. The nut engages a thread on a sleeve 112, which sleeve is guided to rise or fall, but not rotate, by a finger 113. The sleeve houses a spring threaded over a rod 118 carrying at its lower end a ball 120 adapted to close the lower end of the tubular piston 76. The valve rod has a shoulder engaging a baffle 126 normally seated against the lower end of the sleeve. A bumper is provided, for cushioning the rise of the head by the spring 50, comprising a threaded rod 54 carried by the slide 42 and carrying washers 64 of leather arranged to engage a projection 62 on the frame. In operation, a shoe is positioned over the jack and the slide 42 depressed by a treadle 66 until the tread and rear abutments contact with the heel. During this descent of the slide oil passes by the valve 120 from inside the tubular piston to the cylinder. When the clamps engage the heel firmly, the treadle fulcrums about the lower end of its connection 68 with the slide 42 and elevates a rod 132 tripping a one-revolution clutch and causing the rotation of the drive shaft 24. The cam 92 thereupon depresses the piston 76, which first takes up the predetermined lost motion between itself and the valve, and, on the closure of the valve, depresses the slide 42 and clamps the work by power while a cam 20 causes the driving of the heel-attaching nails N. If the clamping pressure so produced is too light, the handle 108 is moved to raise the valve. If the full movement of the handle 108 is insufficient for this purpose, the finger 113 is unclamped from the sleeve and this is rotated to raise the valve rod, the handle 108, thereafter, adjusting through an altered range.