DAMPER AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a damper to generate arbitrary set torque with excellent reproducibility through simple constitution. SOLUTION: The damper comprises a shaft member 2 provided with blade parts 4a and 4b formed on the outer periphery of a shaft part 3; a cylindrical casing 1 relatively rotatably incorporating the shaft member; and oil chambers A-D formed between the outer periphery of the shaft member and the inner periphery of the casing 1. A sliding protrusion part is formed on the outer periphery of the shaft part. Communication passages 5a and 5b capable of effecting intercommunication between a pair of adjoining oil chambers of oil chambers surrounded by the blade parts and the protrusion part are caused to run through the shaft part. Further, in the relative rotation range of the shaft member 2, at least one opening of the communication passage is closed by protrusion parts 8a and 8b of the casing.