A handcuff having an operating mechanism comprised of a planar base, a first working gear, an idler gear, a control pin and a swing arm;
- said planar base having perpendicularly attached thereto a first gear axle, an idler gear axle and a swing arm axle, wherein said swing arm axle is positioned on said planar base a first fixed distance from said first gear axle, and said idler gear is positioned on said planar base a second fixed distance from said first gear axle, and a third fixed distance from said swing arm axle;
- said first working gear is rotatably mounted on said first gear axle to enable said first working gear to rotate around said first gear axle in a plane parallel to the plane of said planar base, wherein said first working gear is a wheel having a first radius and teeth mounted oh the outer edge thereof;
- said swing arm is rotatably mounted on said swing arm axle to enable said swing arm to rotate around said swing arm axle in a plane parallel to the plane of said planar base, wherein said swing arm is a curvilinear member having a second radius and teeth mounted on the outer edge of a first portion thereof, wherein the distance from said outer edge of said first portion of said swing arm to said swing arm axle is said second radius;
- said first fixed distance is substantially equal to the sum of the lengths of said second radius and said first radius, whereby said teeth on said first working gear and said teeth on said swing arm are in contact each with the other upon rotation of said swing arm around said swing arm axle, wherein said teeth on said first working gear and said teeth on said swing arm are adapted to intermesh upon said contact;
- said idler gear is rotatably mounted on said idler gear axle to enable said idler gear to rotate around said idler gear axle in a plane parallel to the plane of said planar base, wherein said idler gear is a wheel having a third radius and teeth mounted on the outer edge thereof;
- said teeth on said idler gear and said teeth on said first working gear are in contact each with the other, wherein said teeth on said idler gear and said teeth on said first working gear are adapted to intermesh upon said contact;
- said control pin is comprised of a linear rod slidably mounted on and parallel to said planar base in a position opposed to said idler gear, said linear rod having a proximal end, a distal end and a biasing means abutting said distal end to urge said proximal end into contact with said teeth on said idler gear, wherein said proximal end of said linear rod is adapted to contact said teeth on said idler gear to permit rotation of said idler gear around said idler gear axle in one rotational direction and to prevent rotation of said idler gear around said idler gear axle in the opposite rotational direction, thus permitting rotation of said first working gear around said first gear axle in one direction and to prevent rotation of said first working gear around said first gear axle in the opposite rotational direction.