The design of the electromagnetic counter featuring number wheels (8) prevents pull-back of the ratchet wheel (3) during the return stroke of the drive pawl (1). The pull-back may occur when the guard pawl (7) is thrown-off during the high speed operation. The underside of the drive pawl (1) forms a bounce-controlling surface (9) set at an angle to the path of the pawl. When the guard pawl (7) is thrown by the forward stroke of drive pawl, it forces the control surface (9) into the engagement position for holding by gravity. The forced locking movement of the pawl (7) is, therefore, achieved without complicated methods which would make the unit more expensive.
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