Band length extension mechanism, band, and timepiece

Abstract

There is provided a band length extension mechanism that allows switching between a folded state and a deployed state, the band length extension mechanism including: an adjustment link; a link piece; an extension piece that couples the adjustment link and the link piece to each other; and a locking member, in which the extension piece is rotatably coupled to the adjustment link at a first shaft and is rotatably coupled to the link piece at a second shaft, in the folded state, the extension piece is stored in an overlapping manner with the adjustment link and the link piece, in the deployed state, the adjustment link, the extension piece, and the link piece are deployed and extended, the locking member is slidably provided on one surface of the adjustment link, and in the folded state, the locking member is engaged with the extension piece to achieve locking.

1 . A band length extension mechanism that switches between a folded state and a deployed state, the band length extension mechanism comprising:
 an adjustment link; a link piece; an extension piece that couples the adjustment link and the link piece to each other; and a locking member, wherein   the extension piece is rotatably coupled to the adjustment link at a first shaft and is rotatably coupled to the link piece at a second shaft,   in the folded state, the extension piece is stored in an overlapping manner with the adjustment link and the link piece,   in the deployed state, the adjustment link, the extension piece, and the link piece are deployed and extended,   the locking member is slidably provided on one surface of the adjustment link, and   in the folded state, the locking member is engaged with the extension piece to achieve locking.   
     
     
         2 . The band length extension mechanism according to  claim 1 , wherein
 the engagement is meshing of a projection portion of the locking member with a recess portion of the extension piece.   
     
     
         3 . The band length extension mechanism according to  claim 2 , wherein
 an elastic member is provided between the adjustment link and the locking member, and   in the folded state, the projection portion of the locking member is pressed by the elastic member toward the recess portion of the extension piece.   
     
     
         4 . The band length extension mechanism according to  claim 3 , wherein
 the elastic member is a coil spring.   
     
     
         5 . The band length extension mechanism according to  claim 3 , further comprising:
 a clasp portion including a length adjustment mechanism including an engagement pin attached to the adjustment link, wherein   the lock is released by sliding the locking member to remove the projection portion of the locking member from the recess portion of the extension piece in a state where the adjustment link is raised with respect to the clasp portion.   
     
     
         6 . The band length extension mechanism according to  claim 3 , further comprising:
 a clasp portion including a length adjustment mechanism including an engagement pin attached to the adjustment link, wherein   in the folded state, when the length adjustment mechanism is set to the longest length, only the link piece is exposed in an appearance between the clasp portion and a first band.   
     
     
         7 . The band length extension mechanism according to  claim 6 , wherein
 the link piece has a top plate portion that covers the extension piece in the folded state.   
     
     
         8 . The band length extension mechanism according to  claim 5 , wherein
 the length adjustment mechanism is provided to change a position of the engagement pin by pressing the adjustment link toward the clasp portion in a state where the adjustment link is raised, and   when the lock is released, the locking member slides in a direction away from the clasp portion.   
     
     
         9 . A band comprising:
 the band length extension mechanism according to  claim 5 ; and   a first band and a second band that is paired with the first band, wherein   the band length extension mechanism is provided between the clasp portion and the first band.   
     
     
         10 . A timepiece comprising the band according to  claim 9 .