Rotary shock absorber with a controlled damping rate

A rotary shock absorber for damping relative movement between parts, said rotary shock absorber comprising:

• a housing connectable to one of the parts and defining at least one chamber for a field-responsive fluid;
• a shaft having its axially opposite ends connectable to another one of the parts and being supported for rotation about its longitudinal central axis relative to said housing;
• a rotor blade disposed in said chamber and connected with said shaft and extending radially of said shaft, the movement of said rotor blade in said chamber being resisted by the fluid;
• and
• at least one energizeable, arcuate-shaped electromagnetic coil connected with said housing for, when energized, applying an energy field to the field-responsive fluid in said chamber to vary the resistance to shear of the fluid as a function of the energy field acting thereon, said shaft rotating about its longitudinal central axis relative to said housing and said rotor blade moving in said chamber as the parts move relative to each other, the resistance to relative movement of the parts varying as a function of the resistance to movement of said rotor blade in said chamber.

An apparatus for damping relative movement between parts, said apparatus comprising:

• a housing connectable to one of the parts and defining at least one chamber for a field-responsive fluid;
• a shaft having its axially opposite ends connectable with another one of the parts and being supported for rotation about its longitudinal central axis relative to said housing;
• a rotor blade disposed in said chamber and connected with said shaft and extending radially of said shaft, the movement of said rotor blade in said chamber being resisted by the fluid;
• and
• yieldable means connected between said housing and axially opposite end portions of said shaft for providing a fluid-tight seal between said housing and said axially opposite end portions of said shaft to prevent leakage of the fluid from said chamber, said yieldable means including an outer sleeve press-fit into said housing, an inner sleeve press-fit on an end portion of said shaft, and an elastomeric member which is connected between said inner and outer sleeves and which stretches upon rotation of said shaft relative to said housing.

An apparatus for damping relative movement between parts, said apparatus comprising:

• a housing connectable to one of the parts and defining at least one chamber for a field-responsive fluid;
• a shaft having its axially opposite ends connectable with another one of the parts and being supported for rotation about its longitudinal central axis relative to said housing;
• a rotor blade disposed in said chamber and connected with said shaft and extending radially of said shaft, the movement of said rotor blade in said chamber being resisted by the fluid, said rotor blade including an end portion connected with said shaft and a blade portion extending into said chamber, said blade portion having a plurality of magnetic segments disposed along the radial extent of said blade portion and having a plurality of nonmagnetic segments interposed between said plurality of magnetic segments;
• and
• yieldable means connected between said housing and axially opposite end portions of said shaft for providing a fluid-tight seal between said housing and said axially opposite end portions of said shaft to prevent leakage of the fluid from said chamber, said yieldable means including an outer sleeve press-fit into said housing, an inner sleeve press-fit on an end portion of said shaft, and an elastomeric member connected between said inner and outer sleeves.