Steering mechanism

Claim 2

A steering mechanism for causing a vehicle to follow a current-carrying wire comprising wheel means movable to effect vehicle steering, drive means for moving said wheel means for steering purposes, said drive means including a driven member, a pair of clutches having output members drivingly connected with said driven member and applying oppositely directed driving forces thereto, means constantly energizing said clutches to apply positive opposite and equal driving forces to said driven member when said vehicle is properly positioned relative to said wire, and sensor means for sensing deviation of said vehicle from said wire and operable in association with said energizing means to control said clutches in response thereto to change the driving torque applied to said driven member thereby and thereby effect rotation of said driven member to effect movement of said wheel means.

Claim 3

A steering mechanism as defined in claim 1 wherein said output members of said pair of clutches are drivingly connected with separate gears, said gears having torque applied thereto by said output members of said clutches tending to rotate said gears in opposition to each other, and one of said gears being drivingly connected with said driven member.

Claim 4

A steering mechanism as defined in claim 1 wherein said clutches comprise electromagnetic clutches having electrical coils the degree of energization of which controls the amount of torque transmitted to the output member of the clutch.

Claim 5

A steering mechanism as defined in claim 3 wherein said sensor means comprises a deviation sensor operatively associated with a control circuit, said circuit including said coils of said clutches and controlling the energization thereof.

Claim 6

A steering mechanism as defined in claim 4 wherein said circuit includes means for increasing the degree of energization of one of said coils while simultaneously decreasing the degree of energization of the other of said coils so as to effect movement of said driven member when the vehicle is not properly positioned relative tO the wire.

Claim 7

A steering mechanism as defined in claim 4 wherein said circuit comprises a pair of transistors each of which is associated with one of said electromagnetic coils to control the degree of energization thereof.

Claim 8

A vehicle-steering mechanism as defined in claim 4 further including means responsive to rotation of said driven member for producing a speed feedback signal to said circuit means to effect a control on said circuit means.

Claim 9

A steering mechanism as defined in claim 7 wherein said means responsive to rotation of said input member comprises a tachometer and said circuit means includes circuit means to which said sensor means applies a signal and said tachometer applies a signal which opposes the signal by said sensor means and which circuit means controls said transistors.

Claim 10

A steering mechanism as defined in claim 1 wherein said vehicle has motor means for driving said vehicle and means for deenergizing said motor means to stop the vehicle when said sensor means moves a predetermined distance away from said wire.

Claim 11

A steering mechanism for causing a vehicle to follow a current-carrying wire comprising wheel means movable to effect vehicle steering, drive means for moving said wheel means for steering purposes, said drive means including a driven member, a pair of clutches having output members drivingly connected with said driven member and applying oppositely directed driving forces thereto, means constantly energizing said clutches to apply positive opposite and equal driving forces to said driven member when said vehicle is properly positioned relative to said wire, sensor means for sensing deviation of said vehicle from said wire, circuit means operable in association with said energizing means to control said clutches in response to said sensing means to change the driving torque applied to said driven member thereby and thereby effect rotation of said driven member to effect movement of said wheel means, and means responsive to rotation of said driven member for producing a speed feedback signal to said circuit means to effect a control on said circuit means.

Claim 12

A steering mechanism for causing a vehicle to follow a current-carrying wire comprising wheel means movable to effect vehicle steering, drive means for moving said wheel means for steering purposes, said drive means including a driven member, a pair of clutches having output members drivingly connected with said driven member and applying oppositely directed driving forces thereto, means constantly energizing said clutches to apply positive opposite and equal driving forces to said driven member when said vehicle is properly positioned relative to said wire, sensor means for sensing deviation of said vehicle from said wire, circuit means operable in association with said energizing means to control said clutches in response to said sensing means to change the driving torque applied to said driven member thereby and thereby effect rotation of said driven member to effect movement of said wheel means, and means responsive to rotation of said driven member for producing a speed feedback signal to said circuit means to effect a control on said circuit means.

Claim 13

A steering mechanism as defined in claim 10 wherein said output members of said pair of clutches are drivingly connected with separate gears, said gears having torque applied thereto by said output members of said clutches tending to rotate said gears in opposition to each other, and one of said gears being drivingly connected with said driven member.

Claim 14

A steering mechanism as defined in claim 11 wherein said clutches comprise electromagnetic clutches having electrical coils the degree of energization of which controls the amount of torque transmitted to the output member of the clutch.

Claim 15

A steering mechanism as defined in claim 12 wherein said sensor means comprises a deviation sensor operatively associated with a control circuit, said circuit including said coils of said clutches and controlling the energization thereof, and means for increasing the degree of energization of one of said coils while simultaneously decreasing the degree of energization of the other of said coils so as to effect movement of said driven member when the vehicle is not properly positioned relative to the wire.