Working at the right height

The automotive industry in particular is currently giving a lot of thought to how workstations in small parts production need to be designed in order to be able to employ older employees or those with restricted mobility. In the welding department for small car body parts, spot and projection welding machines are used that are operated manually. Due to the low weights of the small parts to be processed there, these jobs are particularly suitable for older employees. People with restricted mobility can also be deployed here. However, this is only possible if additional conditions are created to ergonomically adapt the welding machine and the workplace as a whole to the employee's capabilities.

In collaboration with well-known welding machine manufacturers, Flexlift Hubgeräte GmbH has developed a lift table that can move spot and projection welding machines to the ergonomically correct height. The fact that both standing and seated work is possible was taken into account.

Challenge: the geometry of the machines

The design challenge was to take into account the unfavorable geometry of these machines and still ensure good lateral stability. The center of gravity of the welding fixtures is usually outside the center of gravity of the surface and this causes reaction forces that are difficult to absorb by normal lift table shears. The unfavorable application of force then results in the lift table "rocking" during the lifting and lowering movement. This causes the operator to feel uncomfortable and at the same time considerably shortens the service life of the scissor center bearings. The impulses when closing the welding guns must also be taken into account or absorbed.

Single-head spot welding machine with an FM 3000/70 lifting table Photo: Flexlift

With the FM 3000/70 series, Flexlift has developed a lift table that takes these unfavorable operating conditions into account. The first lift tables of this type have now been successfully in use for several years. They are characterized by their robust design and high availability.

The material supply and removal at these workstations also had to be considered from an ergonomic point of view, as individual adjustability must also be provided here. As container management systems are common in the automotive industry, this aspect also had to be taken into account when selecting suitable lift and tilt devices. During the research, it emerged that the different container sizes and weights meant that the required lifting capacity of the lifting devices was a selection criterion.

Tilt angle of 40 degrees

Another point is the different geometric design of the containers. It quickly became clear that the usual maximum tilt angles of 30 ° -3 5 ° were not sufficient to reach the base position even with high-walled containers. In order to meet the needs of the employees in this respect too, a lift and tilt device had to be designed whose lifting height corresponds to a certain container width and also achieves a tilt angle of 40°.

In order to achieve all these parameters, Flexlift has added two types to its range of lift and tilt devices, the FMP40/85/770 and FG12/52/80-25, to create workstations where employees with musculoskeletal restrictions can be reintegrated into the workplace and older colleagues can carry out their jobs for longer without physical damage caused by one-sided strain.

www.flexlift.de