Security lock

A security lock, comprising:

• a blocking mechanism;
• a lock bolt that interacts with the blocking mechanism;
• a manually operated drive for operating the lock bolt;
• a bolt block having a block position that blocks movement of the lock bolt, said bolt block comprising a pivotable lever that can be operated by an electric drive, said bolt block has a blocking nose formed on a lock bolt side that engages in a correspondingly formed recess in the lock bolt;
• and
• a gearing mechanism arranged between the bolt block and the electric drive, said gearing mechanism being arranged to move the bolt block from a release position into a block position and vice versa, and to block the bolt block from pivoting in the block position;
• wherein the gearing mechanism is a driving and blocking member, which is mounted pivotably on the pivotable lever of the bolt block at a distance from a stationary pivot axis thereof, the driving and blocking member has a recess that engages with a stationary peg, the electric drive is coupled to the driving and blocking member at an articulation point that lies opposite the recess in relation to the movable pivot axis of the driving and blocking member or the articulation point is arranged at an obtuse angle to the position of the recess, and when the bolt block is in the block position the driving and blocking member can be pivoted into a blocking position in which a blocking face of the driving and blocking member can be moved into a position opposite a stationary stop face.