| 摘要 |
A tool (16) for butt-welding two thermoplastic sheets (10, 11) together and a method of welding comprising the steps of(a) providing two sheets of thermoplastic weldable materials (10, 11) each having a first surface (12 and a second surface(11);(b) bringing the two sheets of materials together with their first surfaces (12) confronting each other;(c) positioning an edge of the sheets (10, 11) adjacent a predetermined line;(d) contacting the two sheets (10, 11) with a cutting and welding tool (16) that has an inclined welding surface (18) and a cutting edge (17) that extend in a direction along said predetermined line;(e) urging the tool (16) in a direction towards the two sheets (10, 11) to bring the inclined surface (18) into contact with the two sheets (10, 11), and generating heat so as to melt and fuse the sheets (10, 11) together along said line whilst simultaneously cutting through the two sheets (10,11); and(f) unfolding the two sheets (10, 11) to form a unitary article having the two sheets butt welded along said line with their first surfaces (12) facing in a common direction. The step of generating heat is effected by either means of a radio frequency welding process and the tool (16) constitutes one electrical conductor of a pair of opposing conductors (16, 19) between which an electromagnetic field is generated, or by an ultrasonic welding process where the tool (16) constitutes a horn of an ultrasonic welding machine, and the sheets (10, 11) are positioned between the horn (16) and an anvil (19) of the machine. |
