End of arm tooling
Magnetic grippers are ideal when you want to pick up, place or position flat, steel products with a robot. The applications are very diverse, such as:
- pick-and-place of steel parts
- handling perforated sheets with a robot arm
- unstacking workpieces from crates (bin picking)
- positioning sheets in presses
- stacking or unstacking hot baking tins
The high temperature gripper is suitable for this last example. For example, you can also use it to load and unload high-grade steel in a press; it is formed at high temperatures.
Switching and control of the magnet gripper
The magnet gripper switches pneumatically. This moves the magnetic field and switches it on and off.
Control can be with a 5/3 or possibly a 5/2 valve.
An activated magnet gripper does not release its load, even if the air pressure or power supply is lost. This makes it a safe and reliable end-of-arm solution.
Things to look out for when using magnetic grippers:
- When working with thin sheets (≤ 1 mm) you must consider the ‘peeling off effect’. This reduces the maximum breakaway force. In this situation, it is better to create a construction with multiple smaller grippers (e.g. 40 x 40 mm) than one or two large grippers.
- A sheet can be damaged when the gripper contacts the sheet. If this is a problem, choose the version with a protective polyurethane cap (friction type).
- When working with oiled sheets or with high acceleration of the robotic arm, a sheet can shift position. This, too, can be prevented through use of the type with a polyurethane friction pad.
- Sometimes the surface of a sheet is not flat, so the vacuum does not work. In this case, magnetic grippers are an ideal solution. The more contact surface area the better, but a magnet gripper always works on ferromagnetic steel. Thus on round shapes too.
- The vacuum does not work when there are holes in the sheet; the magnet gripper does. In this case, choose a gripper with larger dimensions than the hole, and test the chosen solution thoroughly.
- For small workpieces, Goudsmit has very small grippers in the assortment. They have a low overall height and give extra strength to hold the workpiece in place. For example, choose type HGR-RO-020.
- For thin sheets (≤4 mm) and oily sheets that stick together, the robot sometimes picks up several sheets together. Sheet separators prevent this. They are available both in permanent and pneumatically switchable versions.