Lens barrel and imaging device

Abstract

The lens barrel includes a first supporting frame, an optical element, a second supporting frame, and a guide shaft. The first supporting frame has a first base portion and a first seat portion that projects in a first direction from the first base portion. The second supporting frame supports the optical element and has a first bearing portion. The guide shaft is coupled to the first seat portion and inserted into the first bearing portion. The first seat portion is disposed within the circumference of the guide shaft when viewed in the first direction.

1 . A lens barrel comprising:
 a first frame having a substantially cylindrical shape and a first axis, the first frame including a first groove portion and a second groove portion, the first groove portion having a closed end portion and an opened end portion and extends along the circumferential direction of the inner periphery of the first frame, the second groove portion being disposed transverse to the first groove portion and substantially parallel to the first axis;   a second frame including a first protruding portion configured to engage the first groove portion, the second frame being configured to rotate relative to the first frame about the first axis and being forwardly and rearwardly immovable relative to the first frame along the first axis; and   a third frame including a second protruding portion configured to pass across the first groove portion and engage the second groove portion, the third frame being forwardly and rearwardly movable relative to the first frame along the first axis,   the length of the closed end portion along the first axis being shorter than the length of the opened end portion along the first axis.   
     
     
         2 . The lens barrel according to  claim 1 , the first groove portion having an intermediate portion that gradually changes between the closed end portion and the opened end portion, the length of the intermediate portion extends between opposing surfaces of the first groove portion along the first axis. 
     
     
         3 . The lens barrel according to  claim 1 ,
 the length of the closed end portion along the first axis is shorter than a length of the second protruding portion along the first axis.   
     
     
         4 . The lens barrel according to  claim 1 ,
 the first groove portion and the first protruding portion are configured to support a bayonet mount,   the second groove portion is a straight groove, and   the second protruding portion is a straight protruding portion configured to engage the straight groove.