| 摘要 |
626,860. Seaming non - metallic sheets. BLAND, A. H. May 30, 1946, No. 16409. [Class 42 (i)] [Also in Groups XV, XVI and XVII] A machine for joining sheets of cellulose or like sheet material comprises a pair of jaws between which the sheets are clamped, the operating faces of the jaws being provided with complementary pyramidal projections and indentations. Lower and upper jaws 18, 20, Figs. 4 and 6, whose operating surfaces are formed respectively with pyramidal projections 42 and indentations 44 of complementary form, are carried respectively on a base 10 and a movable part 14 of a machine, hinged together at 16. Each jaw comprises a channel 30 of aluminium or an alloy thereof, and is screwed to a block 37 secured to the machine by screws 39. A resistance element 32 enclosed in asbestos 34 passes out of the jaw at either end to form a cable, whereby the jaws are electrically heated if required, as when the sheets to be crimped are thermoplastic. The jaws are normally held closed by adjustable springs 22 on the base 10 and acting through cables 78 attached to shackles 82 on arms 68 pivoted at 70 to the part 14. An electric motor 50 on the base drives pinions 62 through reduction gearing 54, and the pinions engage gear-wheels 60 mounted eccentrically on spindles 66 carried by the arms 68. On operation of the motor, the spindles 66 rise along the curved path 84, whereupon U-shaped brackets 86 carried by the spindles abut against stops 88 to open the jaws, the stops 88 being adjustable to vary the length of time the jaws remain open. Alternatively, the parts 10, 14 may be urged apart by a spring, and a handle or foot-pedal may be used to lower the part 14 and close the jaws. According to the Provisional Specification, a thermostatic device may be employed to control the heating of the jaws, and an interlock may be provided in the motor circuit to open the jaws when the motor is switched off, which may be a solenoid operating a cam; in another form, a fractional horse-power motor has a cam on the driving shaft to open the jaw against spring pressure, the motor speed being adjustable according to the sealing rate required. |
