Tugger trains are often used to transport material to production centres in series production installations. They consist of a tractor and a number of trucks, the design of which differs according to their function and load.
Simple shelf trucks may be used where the materials are diverse or quantities low. However, these trucks can be loaded only from the side, which may present problems. This gives rise to high-stress work situations, particularly where materials are heavy.
No machinery standards relevant to tugger-train trailers are known.
The Technical Report ISO/TR 22100-3 describes how ergonomic principles can be applied during the risk reduction process according to ISO 12100 and how ergonomics standards can be applied to machinery. It helps designers take decisions with respect to ergonomics during the machine design process and can also be used when no relevant type C standards are available.
Non-powered trucks for use in tugger trains are often equipped with shelves in order to increase their transport capacity. A benefit of this is that smaller and lighter parts can be transported at a height at which they can be reached more easily. The drawback however is that they restrict access from above to the lower levels. Larger and heavier parts may be difficult to load as a result.
The LKE 800 E3 shelf trolley possesses two shelves on the upper level that can be folded up out of the way when the trolley is not loaded, thereby permitting unrestricted access to the levels below. This not only permits a more comfortable body posture during loading and unloading, but also facilitates the use of lifting gear such as cranes and manipulators, or indeed enables them to be used at all (see also EN 1005-2). Raising of the shelves is also assisted by gas struts, as a result of which even frequent raising of the shelves does not lead to undue stress.
Non-powered trucks for use in tugger trains often possess shelves for better exploitation of their transport capacity. A benefit of this is that smaller and lighter parts can be transported at a height at which they can be reached more easily. The drawback however is that they restrict access from above to the lower levels. Larger and heavier parts may be difficult to load as a result.
The LKE 800 E4.MAV range of shelf trolleys are equipped with withdrawable shelves. These shelves can be withdrawn so far that the entire shelf area can be loaded and unloaded from above. Lifting equipment such as manipulators can also be used more effectively (see also EN 1005-2). Interlocks prevent multiple (loaded) shelves being withdrawn simultaneously and the consequent risk of the trolley tipping.