Rotary damper assembly

A rotary damper assembly comprising:

• a housing extending along a center axis and including an upper portion and a lower portion, said lower portion defining a fluid chamber for containing a magnetorheological fluid and said upper portion defining a compartment in communication with said fluid chamber;
• a magnetic field generator including a magnetic core located between said upper portion and said lower portion, said magnetic core extending along said center axis between said upper portion and said lower portion;
• at least one coil extending about said magnetic core;
• a shaft extending along said center axis through said upper portion and said magnetic core and into said fluid chamber to facilitate magnetorheological fluid flow from said compartment to said fluid chamber;
• a gas cup located in said fluid chamber dividing said fluid chamber into an upper chamber and a lower chamber to accommodate for the expansion of the magnetorheological fluid;
• an end plate coupled to a first end of said lower portion of said housing;
• and
• a charge valve, located on said end plate, for allowing a user to introduce a gas into said lower chamber between said gas cup and said end plate.

A rotary damper assembly comprising:

• a housing extending along a center axis and including an upper portion and a lower portion, said lower portion defining a fluid chamber for containing a magnetorheological fluid and said upper portion defining a compartment in communication with said fluid chamber;
• a magnetic field generator including a magnetic core and located between said upper portion and said lower portion, said magnetic core extending along said center axis between said upper portion and said lower portion;
• at least one coil extending about said magnetic core;
• and
• a shaft extending along said center axis through said upper portion and said magnetic core and into said fluid chamber to facilitate magnetorheological fluid flow from said compartment to said fluid chamber;
• wherein said magnetic field generator includes an insert, containing a permanent magnetic material, for generating a permanent magnetic field to change viscosity of the magnetorheological fluid;
• wherein said magnetic field generator includes an outer body extending about said center axis, said outer body defining a hole for receiving said magnetic core;
• and
• wherein said outer body defines a groove extending about said center axis for receiving said at least one coil.