Rotary damper and closure device with such rotary damper

A closure device for selectively opening and closing a cover, comprising:

• an arm having a roller rotatably mounted on an end thereof and held in rolling contact with the cover;
• a rotary damper having a shaft coupled to said arm for being angularly moved by said arm,
• said rotary damper including
• a casing having a chamber defined therein filled with a viscous fluid;
• a rotating member rotatably disposed in said casing, having a shaft and having a support projection projecting radially outwardly from an outer circumferential surface and extending parallel to an axis of said shaft;
• and
• valve means movably supported on said rotating member for controlling a flow of the viscous fluid in said chamber, said valve means having a flat surface extending essentially radially in alignment with an axis of said shaft and being movably engaged on an outer surface of said support projection to define a fluid path for the viscous fluid between the valve means and an inner circumferential surface of said casing;
• wherein said valve means is movable on said support projection to selectively open and close said fluid path depending on a direction in which said rotating member rotates in said chamber;
• and
• a support base integral with said rotary damper and extending in at least one direction from said rotary damper, said support base being adapted to be fixed to a member with respect to which the cover is to be closed.

A rotary damper comprising:

• a casing having a chamber defined therein filled with a viscous fluid;
• a rotating member rotatably disposed in said chamber, said rotating member having a support projection and an axis of rotation;
• and
• a valve movably having a flat surface extending essentially radially in alignment with the axis of rotation, said valve being engaged on an outer surface of said support projection for radial movement into and out of contact with an inner circumferential surface of said casing to selectively open and close a fluid path defined between said valve and an inner circumferential surface of said casing depending on a direction in which said rotating member rotates in said chamber.

A rotary damper comprising:

• a casing having a chamber defined therein filled with a viscous fluid;
• a rotating member rotatably disposed in said casing, having a shaft and a support projection projecting radially outwardly from an outer circumferential surface of said shaft and extending parallel to an axis of said shaft;
• and
• valve means movably supported on said rotating member for controlling a flow of the viscous fluid in said chamber, said valve means being movably supported on said support projection to define a fluid path for the viscous fluid between the valve and an inner circumferential surface of said casing and to selectively open and close said fluid path depending on a direction in which said rotating member rotates in said chamber, said valve means comprising a valve having a large-diameter outer curved surface, a small-diameter outer curved surface, and at least one fluid passage defined in said large-diameter outer curved surface and said small-diameter outer curved surface.

A rotary damper comprising:

• a casing having a chamber defined therein filled with a viscous fluid;
• a rotating member rotatably disposed in said casing, having a shaft and a support projection projecting radially outwardly from an outer circumferential surface of said shaft and extending parallel to an axis of said shaft, said support projection having a substantially rectangular cross-sectional shape;
• and
• valve means radially movably supported on said support projection for controlling a flow of the viscous fluid in said chamber, said valve means being movably supported on said support projection to define a fluid path for the viscous fluid between the valve and an inner circumferential surface of said casing and to selectively open and close said fluid path depending on a direction in which said rotating member rotates in said chamber.

A rotary damper comprising:

• a casing having a chamber defined therein filled with a viscous fluid;
• a rotating member rotatably disposed in said chamber having a radially outwardly projecting support projection with a substantially rectangular cross-sectional shape;
• and
• a valve radially movably supported on said support projection for radial movement into and out of contact with an inner circumferential surface of said casing to selectively open and close a fluid path defined between said valve and an inner circumferential surface of said casing depending on the direction in which said rotating member rotates in said chamber.

A rotary damper comprising:

• a casing having a chamber defined therein filled with a viscous fluid;
• a rotating member rotatably disposed in said chamber;
• and
• a valve movably supported on said rotating member for radial movement into and out of contact with an inner circumferential surface of said casing to selectively open and close a fluid path defined between said valve and an inner circumferential surface of said casing depending on the direction in which said rotating member rotates in said chamber, said having a large-diameter outer curved surface, a small-diameter outer curved surface, and at least one fluid passage defined in said large-diameter outer curved surface and said small-diameter outer curved surface.