Surface pressure in the hand when holding a drilling machine under different drilling conditions

摘要

The aim was to study how different using conditions influence the surface pressure in the hand while performing simulated drilling tasks using an ordinary impact drilling machine. The pressure on the hand was measured at 16 points. The following parameters were changed and compared with two reference sessions: feed force, working direction, vibration level, balance and the use of an additional handle. Furthermore, the subjects tested four handles covered with rubber of different hardness. Finally, the subjects used impact drills with a narrower, an original and a wider handle. The results showed that the pressure in all situations was highest on the web between the index finger and the thumb. The pressure on this part of the hand increased with increasing feed force and with increasing handle size. The total pressure level increased with increasing feed force compared with the reference sessions. Using a supporting handle, gloves or handles covered with compressible rubber decreased the total pressure level. Vibrations, changed direction of action and changed weight distribution did not influence the total pressure level. Using a narrower or wider handle did not influence the total pressure level compared with the original handle.