To provide a variable lever tumbler lock capable of easily performing conversion into different key form only by rotational operation of a duplicate key from an external space having an opening key hole.

While respective lever tumblers of the lever tumbler lock are formed by combining a tumbler A1A and a tumbler B1B mutually superposed in a substantially C shape, a support shaft 2 is supported so as to be rotatable around the axis of an eccentric shaft projected on its both ends. An engaging projection 9 is formed on the side opposed to the tumbler B1B of a free end part inside edge part of the tumbler A1A, and a plurality of engaging recessed parts 11 engageable with the engaging projection 9 of the tumbler A1A, are respectively formed in an inside edge part of the tumbler B1B. Meanwhile, in the lock for releasing engagement of the engaging projection 9 and the engaging recessed part 11 by pushing down the support shaft 2 in the key difference conversion, the support shaft 2 is rotated by the rotational movement of an inner cylinder by engaging a guiding groove 42 with a guide pin 37 on the tip of an operation arm suspended by the support shaft 2 in the key form conversion.

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