WEBER at the ZOW: TSS ensures cooperation

Connection technologies such as glues or rivets often used in light construction are not optimal because such conventional joining processes are difficult to monitor, only reliable to a certain extent and involve considerable preparation and follow-up work on the joint. A development processing lasting several months produced a process which enables the placement of plastic domes TSSD®. These plastic domes can be used both as a screw dome or as a direct connection element. Depending on the model, the fasteners are detachable or undetachable. While EJOT was responsible for developing a plastic setting element, WEBER was commissioned with implementing special setting equipment. The technology is distributed under the name TSS. The abbreviation relates to the joining process which takes place using the thermal bonding dome. TSS follows this principle:

• After the TSSD® element is sitting on the component to be connected, it is sped up to a previously determined speed and placed under exactly the amount of force required to continuously heat the top layer of the connection material. This upper layer is worn down during this process.
• The melted TSSD® connection element then penetrates into the component and flows into the hollow chamber of the intermediary layer. This produces undercuts, which then create an interlocking connection.
• Once the TSSD® connection element has reached its position, additional fiber content of the outer layer material is embedded in the melted edges of the TSSD® element and force-fitted/form-fitted and firmly bonded to the thermoplast dome after the latter has solidified.

The TSSD® connection element can only be set with a special machine developed by WEBER Schraubautomaten GmbH. It consists of a spindle and an adapted control. The spindle and control ensure that the process is reproducible and can be realized. Parametrization of the process is also achieved via a simple, intuitive user interface. The exact coordination of feed rate, contact force, speed as well as depth control is significant when binding sensitive composites into lightweight construction. WEBER’s setting and control equipment has an integrated strength measurement system and a forward-feed unit which can regulate the entire process on the basis of force and/or route. The progress of the connection process is monitored by a relative measurement system. The process designed cooperatively by WEBER and EJOT offers a large number of advantages for companies in the assembly industry (e.g. furniture assembly):

• TSS can be used in thermo or duroplastic matrix systems.
• The handling strength of the materials to be connected is established within a short time because the cooling time can be minimized.
• Depending on the component, the strength reaches more than 1,500 N in the area of cross tension strength – the limit of the shear tension strength is 2,500 N.
• The parametrization of TSS set process is simply structured.
• The procedure can be used for a wide variety of hollow-chamber structures and is also suitable for material with a thickness of less than 5 mm.
• The procedure does not leave behind any traces or marks on the opposite material side.

TSS technology is used for a variety of light construction materials; for example, when processing EPP foams, Organo sheets, plastic molded parts or other foam structures.