Patent ID: 8360664

Claim:
A thermal imaging camera with an electromechanical shutter device for interrupting a ray path from time to time, the electromechanical shutter device comprising: a motor; a motor shaft driven by said motor; a shutter flag; and a crank-and-rocker mechanism connecting said motor shaft and said shutter flag, said crank-and-rocker mechanism comprising a crank rotatable about said motor shaft, a crank pin mounted on said crank, a rocker and a pivot axis arranged in parallel to said motor shaft, said rocker being pivotally mounted on the pivot axis, said rocker having an elongated hole provided at or adjacent to one end of said rocker and said shutter flag being formed at or adjacent to another end of said rocker, said elongated hole forming a sliding joint together with said crank pin, with which said rocker is pivoted by a pivot angle between first and second selected positions, said first selected position completely interrupting the ray path and said second selected position arranging said shutter completely out of the ray path, said sliding joint transforming an angular velocity of said crank into an angular velocity of said rocker, said sliding joint causes the angular velocity of said crank to transform into a reduction to a zero angular velocity of said rocker as said rocker approaches said two first and second selected positions; and wherein said crank moves through a pivot angle to move said rocker between said first and second positions, said crank and said rocker are arranged to have said pivot angle be greater than 260°.