| 摘要 |
<p>In apparatus for continuously welding superimposed plies of thermoplastic synthetic film, which are moved between mutually opposite heaters facing each other, each heater comprises a heat radiator (23, 24), which is mounted in a housing (15, 16), which on that side which faces the plastic film has a slot (17, 18) that extends throughout the length of the heat radiator. Each of the two housings (15, 16) is formed in addition to the slot (17, 18) with at least one inlet (19, 20) opening for admitting hot air, that is introduced into the housing (15, 16) through a hot air supply pipe (21, 22). <IMAGE></p> |
