The invention relates to a device for heat sealing a film lid placed on the rim of a glass, the device comprising a deformable and thermally conductive element designed to press against the film lid and the rim and to heat the film lid and the rim. A peripheral portion of the conductive element is arranged to extend beyond the rim. The device has means for hinging and suspending the conductive element, and means for transmitting a pressure force exerted by an actuator to the conductive element, which force transmission means are distinct from the means for hinging and suspending the conductive element.

A synthetic resin-made welding joint that has a pipe end portion into which an end portion of a synthetic resin-made tube is to be fitted and inserted, and that is configured so that the pipe end portion and the tube end portion which is fitted and inserted thereinto are enabled to be welded together by heating of heating means which externally surrounds the pipe end portion, therefore, a synthetic resin-made holder which is fitted and attached onto the pipe end portion is disposed, and a flange for ensuring a radial expansion gap with respect to the heating means is integrally formed in the holder.

A method and apparatus for sealing films. In one embodiment the sealing device comprises a horn and an anvil. The film has a standard portion and an increased portion. Increased energy is applied to the film in the increased portion compared to the energy applied to the standard portion. Such a method allows for sealing of varying number of layers.