Hand tool step drive mechanism, crimping pliers provided with such a mechanism, and crimping method

摘要

The present invention relates to a step drive mechanism to be attached into the hollow body of a tool, making it possible to produce a thrust movement that can be easily carried out. To this end, the mechanism includes: a rack (2) that has a first (3) and a second (4) cog having back-slanted teeth (3a, 4a) arranged on an upper (2a) and a lower (2b) edge, respectively; a front end (2c); a pivotable lever (5) that comprises a hollow top end (5a) receiving a torsion spring (8), bearing against said hollow top end (5a) of the lever and against a thrust pawl (7) pivoting in the hollow body (1) in front of the hollow top end (5a) of the lever, and has a crosspiece (7a) inserted between the teeth (3a) of the first cog (3); and a pivotable locking pawl (8) provided with a crosspiece (8a) inserted between the teeth (4a) of the second cog (4). A compression spring (9) is arranged such as to bear against the locking pawl (8) and against an abutment (2d) located at a rear end (2e) of the rack (2).