With adhesive dispensers based on the endless piston principle, the power is transmitted from the motor to the rotor by means of joints or flexible shafts. For over twenty years ViscoTec has been using an in-house developed flexible shaft in its dispensers, which is protected by US Patent No. 6,877,967B2. The advantage of this version compared to the joints: The flex shaft is hermetically sealed, slim and there are no dead spaces.
In combination with various coated, or ceramic rotors from ViscoTec, the dispense units can be used for any material, from chemically corrosive to highly abrasive.
Flexibility and safety of the flexible shaft are given
The shaft is encased in an elastomer which is the same material used in the stator. This improves the tribological properties: Matched to the coated and ceramic surfaces of the rotors, the cladding ensures longer service life and less tribochemical influence on the rotor-stator combination.
The shaft is hermetically sealed with the elastomer. In this way, foreign or internal contamination is prevented – absolutely nothing gets in, but nothing gets out either. Also, a reaction of the material to be dosed with metal is avoided. Unwanted incrustations, which would have a negative influence on the dosing result, are eliminated.
To give customers and users even more security in their usually highly demanding applications, this flexible shaft has been redesigned and optimized. The previously used soldering process has been replaced by a process that allows a higher degree of frictional contact and even withstands steam sterilization.
The new process combines health, economic and process engineering aspects. In the production process, for example, it is now possible to manufacture without the use of substances that are partly hazardous to water. Complex cleaning and washing procedures as well as energy costs are reduced. The user has an even safer dosing technology at his disposal: A longer service life and greater flexibility promise even more precise and absolutely repeatable dosing results.