초록 ▼

A rotary damper is adapted to exert braking force to an upswung door, a toilet lid or the like when the door is closed and dampen the impact produced by the closing door by a damping force far greater than the one obtained by a conventional rotary damper using viscous shearing resistance. The rotary

A rotary damper is adapted to exert braking force to an upswung door, a toilet lid or the like when the door is closed and dampen the impact produced by the closing door by a damping force far greater than the one obtained by a conventional rotary damper using viscous shearing resistance. The rotary damper can also make the door open by a force far smaller than a conventional rotary damper. A movable shaft is rotatably housed in a casing and has a cylindrical shaft section including an arcuate non-resilient section extending from a peripheral edge thereof to an axial base line close to the other free peripheral edge thereof and an eccentric resilient section extending from the axial base line to the other free peripheral edge thereof with its eccentricity increasing as a function of the distance from the base line relative to the radius of curvature of the inner peripheral surface so as resiliently abut the inner peripheral surface. The frictional force between the eccentric rest section and the inner peripheral surface increases when the movable shaft is driven to rotate to close the door to which it is fitted but falls remarkably when the movable shaft is driven to rotate in the opposite sense to open the door.

대표청구항 ▼

1. A rotary damper comprising a casing and a movable shaft having a cylindrical shaft section loosely, freely rotatably and unreleasably fitted into an inner cavity of the casing as defined by an inner peripheral surface thereof and a shaft end section linked to the cylindrical shaft section and pro

1. A rotary damper comprising a casing and a movable shaft having a cylindrical shaft section loosely, freely rotatably and unreleasably fitted into an inner cavity of the casing as defined by an inner peripheral surface thereof and a shaft end section linked to the cylindrical shaft section and projecting from an opening of the casing, said cylindrical shaft section of the movable shaft including an arcuate non-resilient section extending between a peripheral edge to an axial base line and an eccentric resilient section extending between said axial base line to another free peripheral edge with an eccentricity of said eccentric resilient section increasing as a function of a distance from said base line so as to resiliently abut the inner peripheral surface.