The Thomson LC 2000 lifting columns are self-supporting and height adjustable.
In the past, Videojet, a manufacturer of coding, printing, and laser marking products, fluids and accessories for the product identification industry, used carts consisting of wire boxes on wheels to move inkjet printing and laser marking products from station to station during the assembly process. The problem was the height of the work surface could not be adjusted; so, tall and short operators had difficulty reaching the printer for assembly operations. In addition, the cart was not able to store subassemblies that traveled with the printer, so they had to be carried by hand and sometimes were misplaced. Videojet overcame this problem by building a custom cart using the Thomson LC2000 lifting column to move the work surface up and down for operator comfort and ergonomics.
In manufacturing, VideoJet had recently moved from typical stationary workstations to mobile cart workstations. However, operators expressed concern over the difficulties of working with the carts, primarily because they had difficulty either reaching up to or bending down to the printers in the carts. Engineers first considered purchasing a cart and looked at a number of off-the-shelf alternatives. Most readily available carts offered only a manual, mechanical height adjustment requiring extra time to adjust. This would also create difficulties for smaller operators when heavier products were on the cart. A few offered an electrical height adjustment, but they were expensive and the amount of adjustment did not fully accommodate the differences in height among the operators. None of the carts offered for sale could accommodate the assemblies that travel with the printers.
Engineers began looking at ways to make their own cart. The main challenge was finding a lifting column that could deliver the full range of motion required to accommodate the height differences between the company’s shortest and tallest operators. They found the Thomson LC2000 lifting column, which moves from a compact collapsed position to a fully extended position along a single linear axis, while achieving a retraction to extension ratio in excess of 2:1. The aesthetic design of the extruded aluminum profiles on the LC2000 allows it to be a visible component, which greatly reduced the effort and cost involved in building the custom carts. The custom cart also includes shelves that hold the subassemblies that travel with the printer and incorporates electrostatic discharge (ESD) protection.
Engineers selected the LC2000 lifting column because it provides a low retracted-length-to-stroke-length ratio to easily accommodate operators from under five feet to well above six feet tall.
The LC2000 is built around a telescoping lead screw driven by a geared dc motor. This design provides quiet operation and high load capacity with minimum current draw. Engineered polymer bushings are used as the guiding technology between the profiles, creating a high moment load capability in a compact envelope. The lifting column is maintenance free, has built-in end of stroke limit switches and uses dynamic braking for short and consistent stops. With power off, the integrated load holding brake keeps the unit in position. An encoder option is available for synchronous operation of multiple columns, but was not needed for this single axis application.
Thomson Linear
www.thomsonlinear.com
Filed Under: Motors • dc