Power steering system

A steering system comprising:

• a housing;
• a first member supported by said housing for movement relative to said housing;
• a second member supported by said housing for movement relative to said housing and said first member;
• means for moving steerable vehicle wheels in response to relative movement between said first and second members;
• means for resisting relative movement between said first and second members, said resisting means including surface means defining a chamber circumscribing said first member and disposed in said housing, and material located in said chamber having a viscosity which varies as a function of the magnitude of an energy field acting thereon to vary the resistance to relative movement between said first and second members;
• means for applying the energy field to act on the material, the energy field having a magnitude which varies as a function of the speed of the vehicle;
• return spring means for biasing said first and second members to an initial position, said return spring means being connected to said first member at a location adjacent said chamber, said return spring means being connected to said second member at a location adjacent said chamber.

A steering system comprising:

• a housing;
• a first member supported by said housing for movement relative to said housing;
• a second member supported by said housing for movement relative to said housing and said first member;
• means for moving steerable vehicle wheels in response to relative movement between said first and second members;
• said first and second members including portions defining a chamber disposed between said first and second members in said housing;
• material located in said chamber having a viscosity which varies as a function of the magnitude of a magnetic energy field acting thereon to vary the resistance to relative movement between said first and second members;
• and
• an electromagnet circumscribing said portions of said first and second members and said chamber for applying the energy field to act on said material having a magnitude which varies as a function of the speed of the vehicle;
• said portion of said second member defining said chamber including a magnetic portion and a non-magnetic portion, said non-magnetic portion being located adjacent said electromagnet.

A steering system comprising:

• a housing;
• first and second valve members movable relative to each other to port fluid to a power steering motor;
• a first member connected with said first valve member for movement along with said first valve member;
• a second member connected with said second valve member for movement along with said second member;
• said first and second members including portions defining a chamber disposed between said first and second members in said housing;
• material located in said chamber having a viscosity which varies as a function of the magnitude of a magnetic energy field acting thereon to vary the resistance to relative movement between said first and second members;
• and
• an electromagnet circumscribing said portions of said first and second members and said chamber for applying the energy field to act on said material having a magnitude which varies as a function of the speed of the vehicle;
• said portion of said second member defining said chamber including a magnetic portion and a non-magnetic portion, said non-magnetic portion being located adjacent said electromagnet,
• return spring means for biasing said first and second members to an initial position, said return spring means being connected to said first member at a location adjacent said chamber, said return spring means being connected to said second member at a location adjacent said chamber.