An attachment part (10) for connecting to a structural part (30). The attachment part (10) has an attachment part longitudinal axis (A), and a weld portion (11) to be welded to the structural part (30) by torsional ultrasonic welding. The weld portion (11) has a contact surface for contact with a torsion sonotrode (70), and a weld surface (13) for connecting to the structural part (30). The weld portion (11) is delimited, at least portionally, by an inner vibration decoupling zone (14). The inner vibration decoupling zone (14), at least portionally, surrounds an inner portion of the attachment part (10).

A method for joining two objects by anchoring an insert portion provided on one of the objects in an opening provided on the other one of the objects. The anchorage is achieved by liquefaction of a thermoplastic material and interpenetration of the liquefied material and a penetrable material, the two materials being arranged on opposite surfaces of the insert portion and the wall of the opening. Before such liquefaction and interpenetration, an interference fit is established in which such opposite surfaces are pressed against each other, and, for the anchoring, mechanical vibration energy and possibly a shearing force are applied, wherein the shearing force puts a shear stress on the interference fit.

A linear friction welding machine comprising a compression unit and an oscillator unit, each having a clamping holder for a workpiece. Both clamping holders are configured such that workpieces are held with the surfaces thereof to be welded, aligned and facing each other. The clamping holder of the compression unit is linearly movable relative to the clamping holder of the oscillator unit, and the latter is movable in an oscillating manner at right angles transversely with respect to the direction of travel of the compression unit and fixed to ends of vertical and horizontal supports which can be deflected laterally in a sprung manner in the oscillation direction, the other ends of which are anchored rigidly on supporting bodies. The supports are flexible under deflection in the oscillation direction but are designed to resist buckling when the clamping holders are loaded in the direction of travel of the compression unit.

An add-on part (10) for connecting to a component (30). The add-on part (10) has a longitudinal axis (A) and a welding section (11) to be welded to the component (30) by torsional ultrasonic welding. The welding section (11) has a contact surface (12) for contact with a torsion sonotrode (70) and a welding surface (13) for connecting to the component (30). The welding section (11) is delimited, at least in some sections, by an inner vibration-decoupling zone (14). The inner vibration-decoupling zone (14) extends, at least in some sections, at an inclination to or parallel to the longitudinal axis (A). The method comprises a) bringing the welding surface (13) in contact with a welding region (31), b) applying a force to the contact surface (12) such that the welding surface (13) is pressed against the welding region (31), and c) introducing a torsional ultrasonic vibration into the welding section.

The invention relates to a method for welding a polyamide plastic and a poly(meth)acrylateparticularly a polymethyl methacrylateplastic using a primer, said primer containing at least one copolymer synthesised from at least one styrene or styrene derivative and at least one maleic anhydride or maleic anhydride derivative. The invention also relates to correspondingly welded products.

A method of forming a weld joint is provided. A first component having a base portion and a flange extending from the base portion is provided. A second component is provided. The second component and the flange are brought into abutment and a load is applied to the flange via the second component. The flange is biased against the second component by a reaction of the first component to the load. One of the first and the second components is vibrated to form a weld joint between at least a part of the second component and at least a part of the flange.

A method for joining two objects by anchoring an insert portion provided on a first object in an opening provided on a second object. The anchorage is achieved by liquefaction of a thermoplastic material and interpenetration of the liquefied material and a penetrable material, the two materials being arranged on opposite surfaces of the insert portion and the wall of the opening. During the step of inserting the insert portion in the opening and/or during anchorage a clamping force is applied to opposing surfaces of the second object to prevent the second object from cracking or bulging.

A spring package for a vibration welding device includes a first longitudinal bar for a fixed connection to a frame of the vibration welding device and a second longitudinal bar parallel to and movable with respect to the first longitudinal bar as well as for connection to a tool. A first axis of the spring package extends halfway between and parallel to the longitudinal axis of the first and second longitudinal bar. A plurality of leaf springs are further provided, each connected with a first end to the first longitudinal bar and with a second end to the second longitudinal bar, wherein a second axis of the spring package extends perpendicular to the first axis as well as, in an inactive state of the spring package, parallel to the plurality of leaf springs so that a spring center line extends, in an inactive state of the spring package, parallel to the second axis in the middle of the leaf spring. Each of the plurality of leaf springs includes a first portion adjacent to the first and/or second longitudinal bar, the first portion consisting of at least one radius so that the first portion is formed concave with respect to the spring center line. The first portion transitions continuously into a second portion which is formed convex with respect to the spring center line, and the second portion transitions continuously into a center portion adjacently arranged relative to the first axis so that a thickness of the respective leaf spring is at the lowest in the center portion, especially at the first axis.

In the vicinity of an opening end of a first liner constituent member and a second liner constituent member made of a resin material, a flange portion is formed. After end surfaces of the opening end are abutted and joined to each other, the flange portion is removed in such a way that a part of a bottom portion remains. The remaining amount of protrusion is set such that the joint strength of a joint portion is not less than the tensile strength of the resin material or not less than the cohesion failure strength of the joint portion.

A cam assembly in a linear friction welding system includes two power shafts. Each of the shafts have two timing gears mounted thereupon. For one of the shafts, one of the timing gears includes a slot extending within the timing gear which is formed as an arc about a center of rotation of the power shaft. The other timing gear on that shaft includes a fixed pin which extends into the slot. A cross-over shaft is operably connected to both power shafts.