| 摘要 |
1322849 Seaming non-metallic sheet material BRANSON INSTRUMENTS Inc 23 Nov 1971 [27 Nov 1970] 54348/71 Heading B5K In a method of ultrasonically seaming a workpiece fed continuously past a resonator 22, the velocity at which the resonator 22 resonates is adjusted in dependence upon the rate of which the workpiece is fed past the resonator. The velocity of the resonator is the peak displacement amplitude at the output surface of the resonator per unit of time in a direction toward the workpiece. The resonator 22 is vibrated by a magnetostrictive or piezoelectric transducer supplied with high frequency electrical energy and its work surface is mounted to form, with a rotatable anvil wheel 24, a nip through which the material to be bonded, e.g. woven fabric made wholly or partially of thermoplastic fibres, is passed. The work surface of the resonator is disposed at an antinodal region. An electrical power supply 26 is mounted to the work-table 12 and supplies h.f. energy to the transducer. A foot control 28 is connected by a rod 30 to a control box 32 which has a dual function i.e. controlling the feed rate of the material and controlling the velocity of the resonator 22 in a predetermined and co-ordinated manner such that the velocity of the resonator increases linearly with increasing feed rate but at a rate which is less than the increase of the feed rate. As shown in Fig. 2, the wheel 24 is mounted on a shaft 36 extending from a gear reducer 38 driven by an electric motor 40 and is exchangeable for a wheel having a different raised pattern thereon, for examples see Fig. 3. When a knee operable control 34 is moved to the right against the action of a spring 44, a switch 46 is actuated to actuate a solenoid valve (not shown) to cause a piston working in a cylinder to lift the resonator 22 by a predetermined amount to facilitate insertion and removal of workpieces. Electrical circuits (n.s.) for the control of the machine are described. |
