A method of fastening at least one second object to at least one first object, wherein mechanical vibration acts from a sonotrode on the second object to fasten the second object to the first object. Between the sonotrode and the second object, an auxiliary sheet is placed, for example of paper. After the vibration stops, the auxiliary sheet is displaced relative to the sonotrode for a next fastening step.

An assembly is provided for induction welding. This assembly utilizes a heat shield (e.g., a mica heat shield) with a recess. An induction welding coil may be disposed within this heat shield recess during induction welding operations. The wall thickness of the heat shield within the recess may be reduced to enhance heat transfer to a workpiece during induction welding operations. Members may engage the heat shield on opposite sides of the recess (and that have an increased wall thickness) to support both the heat shield and the workpiece during induction welding operations, during which a biasing force may be exerted on both the heat shield and workpiece.

An assembly is provided for induction welding. This assembly utilizes a heat shield (e.g., a mica heat shield) with a recess. An induction welding coil may be disposed within this heat shield recess during induction welding operations. The wall thickness of the heat shield within the recess may be reduced to enhance heat transfer to a workpiece during induction welding operations. Members may engage the heat shield on opposite sides of the recess (and that have an increased wall thickness) to support both the heat shield and the workpiece during induction welding operations, during which a biasing force may be exerted on both the heat shield and workpiece.

Methods and apparatus' for induction welding a first workpiece to a second workpiece at a welding region may include a metallic strip. The metallic strip may be a mesh. The properties of the metallic strip, such as, for example, pore size, thickness, and density, may be configured to conduct heat uniformly across the welding region and prevent eddy current formation across a workpiece. The metallic strip may be embedded in a workpiece or may be fixed to an induction welding tool that acts on the welding region during induction welding. A removable polymer tape may be disposed between a workpiece and a metallic strip fixed to an induction welding tool. The workpieces may be thermoplastic composite structures and thermoplastic composite stiffeners in aircraft structures.

Methods and apparatus' for induction welding a first workpiece to a second workpiece at a welding region may include a metallic strip. The metallic strip may be a mesh. The properties of the metallic strip, such as, for example, pore size, thickness, and density, may be configured to conduct heat uniformly across the welding region and prevent eddy current formation across a workpiece. The metallic strip may be embedded in a workpiece or may be fixed to an induction welding tool that acts on the welding region during induction welding. A removable polymer tape may be disposed between a workpiece and a metallic strip fixed to an induction welding tool. The workpieces may be thermoplastic composite structures and thermoplastic composite stiffeners in aircraft structures.

A laser welding system for joining first and second thermoplastic workpieces, and including a clamp, an actuator, and a laser source. The clamp includes first and second clamping structures positioned together to engage opposite sides of the workpieces when they adjoin each other. The first clamping structure has a non-flat or irregular surface, facing the first workpiece. The actuator causes the clamping structures to press the first and second workpieces together. The laser source applies laser radiation having a wavelength of 2 microns toward the workpieces to be joined, while they are pressed together by the clamp, to melt irradiated portions of the workpieces to one another. The first clamping structure transmits substantially all of the energy of the laser radiation through the material. The first workpiece has a non-flat or irregular surface facing the first clamping structure, which substantially conforms with the surface of the first clamping structure.

A laser welding system for joining first and second thermoplastic workpieces, and including a clamp, an actuator, and a laser source. The clamp includes first and second clamping structures positioned together to engage opposite sides of the workpieces when they adjoin each other. The first clamping structure has a non-flat or irregular surface, facing the first workpiece. The actuator causes the clamping structures to press the first and second workpieces together. The laser source applies laser radiation having a wavelength of 2 microns toward the workpieces to be joined, while they are pressed together by the clamp, to melt irradiated portions of the workpieces to one another. The first clamping structure transmits substantially all of the energy of the laser radiation through the material. The first workpiece has a non-flat or irregular surface facing the first clamping structure, which substantially conforms with the surface of the first clamping structure.

A sealing system for heat sealing superimposed walls of heat-sealable film material, e.g. in the production of pouches. The sealing section comprises two or more sealing stations arranged in series along a linear path for the superimposed walls dispensed from an infeed section. Each sealing station comprises a sealing device with first and second jaws and an actuator device to move the jaws between an opened position and a clamped position. Each sealing device comprises a motion device that is configured to move the first and second jaws in synchronicity with the superimposed walls when clamped between the first and second jaws. Each sealing station has a cooling device that is configured to continuously cool at least one of the jaws. At least each first jaw comprises at the respective front surface thereof at least one impulse heatable member embodied as a susceptor element that extends along the respective front surface. Each sealing station is configured to perform an integrated impulse sealing and cooling cycle.

A sealing system for heat sealing superimposed walls of heat-sealable film material, e.g. in the production of pouches. The sealing section comprises two or more sealing stations arranged in series along a linear path for the superimposed walls dispensed from an infeed section. Each sealing station comprises a sealing device with first and second jaws and an actuator device to move the jaws between an opened position and a clamped position. Each sealing device comprises a motion device that is configured to move the first and second jaws in synchronicity with the superimposed walls when clamped between the first and second jaws. Each sealing station has a cooling device that is configured to continuously cool at least one of the jaws. At least each first jaw comprises at the respective front surface thereof at least one impulse heatable member embodied as a susceptor element that extends along the respective front surface. Each sealing station is configured to perform an integrated impulse sealing and cooling cycle.

An apparatus is configured to make containers from sheet material. The apparatus includes a supply station for supplying a film having at least one folded portion having three or more film flaps folded and superimposed with respect to each other; a welding station configured to receive the film. The welding station comprises a welding head configured for welding the folded portion of the film and forming a container defining a housing compartment; the welding head comprises a heater made of electrically conductive material whose electrical resistivity, at least in a predetermined temperature range, decreases upon the increase of the temperature of the same electrically conductive material.