Patent ID: 7314320

Claim:
An extendable pivot shaft mechanism of a camera for pivoting a rotatable grip on a camera body to allow said rotatable grip both to rotate about a rotational axis and to move along said rotational axis relative to said camera body, said extendable pivot shaft mechanism comprising: first and second cylindrical members which are concentrically arranged and are fixed to said camera body and to said rotatable grip, respectively; an advancing/retreating lock control member which is supported by said first cylindrical member to be linearly movable along said rotational axis without rotating relative thereto, wherein said advancing/retreating lock control member is operated from outside one of said camera body and said grip; a rotation locking mechanism for changing a state of said advancing/retreating lock control member and said second cylindrical member between a rotation locked state, in which said advancing/retreating lock control member and said second cylindrical member are prevented from rotating relative to each other, and a rotation unlocked state, in which said advancing/retreating lock control member and said second cylindrical members are allowed to rotate relative to each other, in accordance with a linear movement of said advancing/retreating lock control member relative to said first cylindrical member; and a lock biasing device for biasing said advancing/retreating lock control member in a rotation locking direction to cause said rotation locking mechanism to change to said rotation locked state.