Blade driving device and optical instrument

1. A blade driving device comprising:

a board including an opening;

a blade movable between a position receding from the opening and a position overlapping at least a part of the opening;

a drive member driving the blade;

a joint portion provided in the drive member and coupled to the blade; and

a buffering member having a loop shape defined in part by an inner peripheral surface, having an elasticity, abutting the blade at an end of a movable range of the blade, and being deformable such that the loop shape is warped by movement of an unsupported portion of the inner peripheral surface when abutting against the blade, wherein:

a direction of a line connecting the joint portion and a portion of the buffering member is the same as a direction in which the blade moves toward the buffering member when the blade and the buffering member abut each other;

the board includes a holding portion holding a part of the buffering member such that the buffering member is deformable to warp the loop shape;

the holding portion includes a first holding portion arranged outside the buffering member, and a second holding portion arranged inside the buffering member;

the buffering member includes a sandwiched portion sandwiched between the first and second holding portions, and a non-sandwiched portion not sandwiched between the first and second holding portions; and

a given clearance is provided between the second holding portion and the non-sandwiched portion.

2. The blade driving device of claim 1 , wherein the drive member abuts the buffering member together with the blade.

3. The blade driving device of claim 1 , wherein the buffering, member includes a linear portion along an edge portion having a linear shape of the blade, the edge portion being abuttable with the buffering member.

4. The blade driving device of claim 3 , wherein one end of the edge portion having the linear shape of the blade does not abut the linear portion of the buffering member when the blade and the buffering member abut each other.

5. A blade driving device comprising:

a board including an opening;

a blade movable between a position receding from the opening and a position overlapping at least a part of the opening;

a drive member driving the blade;

a joint portion provided in the drive member and coupled to the blade; and

a buffering member having a loop shape defined in part by an inner peripheral surface, having an elasticity, abutting the drive member at an end of a movable range of the blade, and being deformable such that the loop shape is warped by movement of an unsupported portion of the inner peripheral surface when abutting against the drive member, wherein:

a direction of a line connecting the joint portion and a portion of the buffering member is the same as a direction in which the blade moves toward the buffering member when the blade and the buffering member abut each other;

the board includes a holding portion holding a part of the buffering member such that the buffering member is deformable to warp the loop shape;

the holding portion includes a first holding portion arranged outside the buffering member, and a second holding portion arranged inside the buffering member;

the buffering member includes a sandwiched portion sandwiched between the first and second holding portions, and a non-sandwiched portion not sandwiched between the first and second holding portions; and

a given clearance is provided between the second holding portion and the non-sandwiched portion.

6. The blade driving device of claim 5 , wherein the buffering member includes a linear portion along an edge portion having a linear shape of the blade, the edge portion being abuttable with the buffering member.

7. The blade driving device of claim 6 , wherein one end of the edge portion having the linear shape of the blade does not abut the linear portion of the buffering member when the blade and the buffering member abut each other.

8. An optical instrument comprising a blade driving device, the blade driving device including:

a board including an opening;

a blade movable between a position receding from the opening and a position overlapping at least a part of the opening;

a drive member driving the blade;

a joint portion provided in the drive member and coupled to the blade: and

a buffering member having a loop shape defined in part by an inner peripheral surface, having an elasticity, abutting the blade at an end of a movable range of the blade, and being deformable such that the loop shape is warped by movement of an unsupported portion of the inner peripheral surface when abutting, against the blade, wherein:

a direction of a line connecting the joint portion and a portion of the buffering member is the same as a direction in which the blade moves toward the buffering member when the blade and the buffering member abut each other;

the board includes a holding portion holding a part of the buffering member such that the buffering member is deformable to warp the loop shape;

the holding portion includes a first holding portion arranged outside the buffering member, and a second holding portion arranged inside the buffering member;

the buffering member includes a sandwiched portion sandwiched between the first and second holding portions, and a non-sandwiched portion not sandwiched between the first and second holding portions; and

a given clearance is provided between the second holding portion and the non-sandwiched portion.

9. An optical instrument comprising a blade driving device, the blade driving device including:

a board including an opening;

a blade movable between a position receding from the opening and a position overlapping at least a part of the opening;

a drive member driving the blade;

a joint portion provided in the drive member and coupled to the blade; and

a buffering member having a loop shape defined in part by an inner peripheral surface, having an elasticity, abutting the drive member at an end of a movable range of the blade, and being deformable such that the loop shape is warped by movement of an unsupported portion of the inner peripheral surface when abutting against the drive member wherein:

a direction of a line connecting the joint portion and a portion of the buffering member is the same as a direction in which the blade moves toward the buffering member when the blade and the buffering member abut each other;

the board includes a holding portion holding a part of the buffering member such that the buffering member is deformable to warp the loop shape;

the holding portion includes a first holding portion arranged outside the buffering member, and a second holding portion arranged inside the buffering member;

the buffering member includes a sandwiched portion sandwiched between the first and second holding portions, and a non-sandwiched portion not sandwiched between the first and second holding portions; and

a given clearance is provided between the second holding portion and the non-sandwiched portion.