There is a wide variety of dishwashers. Robots are used in their production for a wide variety of tasks. To ensure their process reliability in the long term, a well-known household appliance manufacturer has recently been relying on a triflex RS universal module for very complex robot movements. It ensures that the energy supply to the robot head is always safe and stress-free and that the directional pretension of the triflex R energy chain prevents the formation of annoying loops.
The dishwasher product division of BSH Bosch und Siemens Hausgeräte GmbH manufactures approximately 10,000 dishwashers per day on nine assembly lines. The company responds extremely quickly to the demands of the market. Currently, the product range of the household appliance manufacturer consists of more than 1,000 models. The demands on flexibility in production and assembly are accordingly high. All machines and systems must be able to adapt quickly to changing customer requirements.
For a new task in pre-production, the household appliance manufacturer uses a so-called KR100 comp. robot. Within pre-production, it ensures safe handling when welding two plastic moulded parts. For this purpose, the handling robot has been equipped with a double gripper. It picks up the two half-parts with the mechanical grippers and places them in a welding device. In return, it picks up two finished components and places them on the material handling system. These tasks also created the special challenges that the household appliance manufacturer was confronted with. This is because the gripper rotates by 180° and an additional strong buckling around axis 5 during placement requires an extremely flexible energy supply system. The usual loop formation had to be avoided. In addition, a major focus was on durability. The systems are in operation in three shifts up to six days a week and downtimes are to be avoided as far as possible. The high quantities set in production should always be guaranteed by reliable technology.
In order to ensure the energy supply to the robot head, the robot was equipped with the universal module triflex R set, and only 24 hours elapsed between ordering, delivery and installation. The advantage of the multi-dimensionally moving energy supply system is its compact design, which meant that the energy supply system could be quickly installed on the existing fastening points on the robot in a space-saving manner. The chain brings with it mounting brackets to securely fix the energy chain, a gliding feed-through for tight and parallel guidance on the robot arm, and protectors for defined freedom of movement. Other features of the energy supply system are, for example, a defined bend radius stop-dog, a high torsion resistance of up to 360° or an integrated retaining spring that prevents the formation of loops.
In the specific application at BSH Bosch und Siemens Hausgeräte GmbH, a plate with the electrical box was fixed above the triflex RS universal module, so that only little installation space is required overall. Not only does this have the advantage of remaining within the robot's contour, but the robot arm, against which the chain fits tightly, can serve any application. The energy supply system is designed in such a way that it can easily cope with the maximum tensile forces that occur due to acceleration, speed and the fill weights.
It was not only the compact design that convinced the household appliance manufacturer, but also the quick commissioning of the solution. "While we used to need up to twelve hours for a comparable application, we were able to assemble the universal module within four hours," says Joachim Grandy, who is responsible for the design of special machines in the dishwasher product area. "So we have not only saved set-up and commissioning times, but we also expect to minimise maintenance and servicing times. "
"I saw the system for the first time at the last Motek in Stuttgart. At that time, however, I did not know how quickly we would use it," the designer looks back. Due to the high torsional elasticity on the one hand and on the other hand the energy supply system, which always lies tightly against the robot arm connected with the integrated retaining spring, the universal module displays its strength in the application. "From our point of view, the pilot project has been so successful that it is very likely that it will be used in further robot cells," concludes Joachim Grandy.