Reversing switch assembly for an electric assist steering system

Torque sensitive switch apparatus, comprising:

• first and second coaxial shaft sections connected together by a torsion bar, said first and second shafts being rotatable relative to one another upon the application of torque thereacross, said torque causing said torsion bar to twist;
• first and second base portions fixed respectively to said first and second shaft sections;
• lever means having a first part pivotably coupled to said first base portion, a second part received in a recess in said second base portion, and a third part adapted to receive a roller;
• a roller rotatably mounted to said third part of said lever means, said roller rolling along a path relative to said second base portion upon relative rotation between said first and second shaft sections;
• and
• contact means disposed along said path and including a plurality of normally open electrical contact pairs being actuatable to a closed condition by said roller;
• whereby, upon relative rotation between said first and second shafts, said lever means pivots, said roller rolls over said contact means, and actuates contact pairs closed.

A switch for controlling the application of electrical power to an electric motor, said switch comprising:

• first and second parts coaxially located at spaced apart locations and resiliently connected together for relative rotation therebetween in first and second opposite directions about their common axis, the common axis being a first axis;
• actuatable contact means including a plurality of normally open contact pairs for connecting the electric power to the motor in one direction upon relative rotation of said first and second parts in said first direction and in an opposite direction upon relative rotation of said first and second parts in said second direction;
• and
• actuating means for actuating said contact means upon relative rotation of said first and second parts, said actuating means including at least one pivoting means located radially outwardly of the first axis and pivotable about a second axis transverse to the first axis, said pivoting means including a support portion supported for pivotal movement about the second axis by said second part, a first portion having a distal end at a first distance from the second axis and received in a recess of said first part so as to effect pivotal movement of said pivoting means upon relative rotation of said first and second parts, a second portion having means for actuating certain of said contact pairs closed upon pivotal movement of said pivoting means and located at a second distance from the second axis.

A switch for controlling the application of electrical power to an electric motor, said switch comprising:

• first and second parts which are relatively rotatable with respect to one another in first and second opposite directions about a common axis;
• actuatable contact means carried by said first part for connecting the electric power to the motor in one direction upon relative rotation of said first and second parts in said first direction and in an opposite direction upon relative rotation of said first and second parts in said second direction;
• actuating means for actuating said contact means upon relative rotation of said first and second parts, said actuating means including at least one pivoting means located radially outwardly of the common axis and pivotable about a second axis transverse to said common axis;
• said contact means being electrically connected with the electric motor and a source of electrical power to selectively control the directon of current flow to the motor upon actuation of said contract means in response to the direction of relative rotation of said first and second parts;
• said pivoting means including a support portion supported for pivotal movement about the second axis by said second part, a first portion engageable with said first part at a first distance from the second axis to effect pivotal movement of said pivoting measns upon relative rotation of said first and second parts, a second portion having means for actuating said contact means upon pivotal movement of said pivoting means and located at a second distance from the second axis;
• four terminals disposed circumferentially about the first axis, a first one of said terminals being electrically connected with the motor, a second one of said terminals being electrically connected with the motor, a third one of said terminals being electrically connected to one terminal of the source of electrical power, a fourth one of said terminals being electrically connected to the other terminal of the source of electrical power;
• and
• said contact means includes a plurality of contact pairs, each of said contact pairs having one contact which is supported oor pivotal movement by said pivot means, said plurality of contact pairs being selectively actuatable to move from a normally open condition (i) to a first condition which electrically connects said first and third terminals and which electrically connects said second and fourth terminals and (ii) to a second condition which electrically connects said first and fourth terminals and which electrically connects said second and third terminals.

An apparatus for controlling the application of electric power to an electric motor which is drivingly connected with a steering member of a vehicle, said apparatus comprising:

• a first body portion fixed to an input shaft and supported for rotation about a first axis, said input shaft being connectable with the vehicle steering wheel;
• a second body portion fixed to an output shaft and supported for rotation about the first axis, said output shaft drivingly connected with a vehicle steering member, said input shaft and said output shaft being connected by a torsion bar, applied steering torque causing said torsion bar to twist, said second body portion and said first body portion rotating relative to each other about said first axis in first and second opposite directions depending on the direction of applied steering torque;
• actuable means for effecting the flow of electric current to the motor in one direction in response to relative rotation between said first and second body portions in said first direction and to effect the flow of electric current to the motor in another opposite direction in response to relative rotation between said first and second body portions in said second direction, said actuatable means including four terminals disposed circumferentially about the first axis, a first one of said terminals being electrically connectable with the motor, a second one of said terminals being disposed diametrically opposite said first terminal and electrically connectable with the motor, a third one of said terminals being electrically connectable with a first connector of the power source, a fourth one of the terminals being disposed diametrically opposite said third terminal and electrically connectable to a second connector of the power source, said actuatable means also including normally open plurality of pairs of fixed and movable contacts disposed between adjacent pairs of said terminals, at least two plurality of said pairs of contacts having their respective movable contacts being pivotally supported by respective arms of rockable contact members disposed on the motor terminals and closable against associated fixed contacts carried by the power source terminals upon actuation to permit electric current to flow in one direction to the motor in response to relative rotation between said first and second body portions in said first direction and to permit electrical current to flow in an opposite direction to the motor in response to relative rotation between said first and second body portions in said second direction;
• and
• means for selectively actuating said contact pairs in response to relative rotation between said first and second body portions, said means for selectively actuating said contacts includes a pair of pivoting means located radially outward from the shafts, each of said pivoting means being supported by said second body portion for pivotal movement about a second axis which is transverse to the first axis, each of said pivoting means having a first end portion for engaging a respective recess in said first body portion and having a second portion for engaging as associated one of said arms carrying said rockable contact members to pivotally move said movable contacts to close against associated fixed contacts upon relative rotation between said first and second body portions.