Sonotrode and anvil for ultrasonic welding of plastics, method for producing a plastic container

A combination of a sonotrode and an anvil for ultrasonic welding of plastic,

• wherein said sonotrode comprises:
• a sonotrode surface for the positioning of sonotrode welding contact elements, said sonotrode surface comprising at least one sonotrode surface side;
• and
• at least one row of at least one sonotrode welding contact element provided so that during the welding the at least one row of at least one sonotrode welding contact element is in contact with the plastic, said at least one sonotrode welding contact element comprising:
• a first plateau surface having a first edge and a second edge opposite the first edge;
• a first lateral surface extending from the first edge of the plateau surface, said first lateral surface comprising a first substantially straight surface, said at least one row of at least one sonotrode welding contact element being positioned according to said sonotrode surface side;
• and
• a second lateral surface extending from the second edge of the plateau surface, the second lateral surface being substantially straight,
• wherein said first lateral surface comprises a first curved surface positioned between said first plateau surface and said first substantially straight surface, wherein said first curved surface has a convex outward arch, and
• wherein said anvil comprises:
• an anvil surface is for the positioning of anvil welding contact elements, said anvil surface comprising at least one anvil surface side;
• and
• at least one row of at least one anvil welding contact element provided so that during the welding at least one row of at least one anvil welding contact element is in contact with the plastic, wherein said anvil welding contact element comprises a second plateau surface and a second series of at least one second lateral surface, wherein said second lateral surface comprises a second substantially straight surface, wherein said at least one row of at least one anvil welding contact element is positioned according to said anvil surface side,
• wherein said second series of each said anvil welding contact element of a first row comprises a second adapted lateral surface that joins at least one part of said second plateau surface with at least one part of said anvil surface side, wherein said second adapted lateral surface comprises a second curved surface positioned between said second plateau surface and said second substantially straight surface, wherein said second curved surface has a convex outward arch, and
• wherein said sonotrode welding contact element is positioned in relation to said anvil welding contact element such that said sonotrode welding contact element is positioned during welding next to said anvil welding contact element and is provided to form each at least one part of a weld seam.