Automotive steering system

An automotive steering system for a vehicle with steerable front wheels and steerable rear wheels, said steering system comprising:

• a steering wheel operable by a vehicle user;
• a front pitman arm shaft operably attached to the front wheels;
• a rear pitman arm shaft operably attached to the rear wheels;
• means for providing specific choices of different steering modes through a shift lever, said shift lever being operable by the vehicle user and being selectively movable between a plurality of operating positions, wherein each operating position provides a specific steering mode;
• and
• shaft means for carrying both a first drive means for controlling the turning of the front wheels and a second drive means for simultaneously controlling the turning of the rear wheels, said shaft means being operably attached to and controlled by both the steering wheel and the shift lever the shaft means including a drive shaft rotated by the steering wheel and linearly displaced by the shift lever, wherein the drive shaft is a worm shaft carrying a first set of worm gears disposed to selectively operably engage the front pitman arm shaft and carrying a second set of worm gears disposed to selectively operably engage the rear pitman arm shaft.

An automotive steering system for a vehicle having front wheels and rear wheels, said steering system comprising:

• a steering wheel operable by a vehicle user;
• front drive means functionally connected with front steering linkage means, said front steering linkage means being functionally connected with the front wheels;
• rear drive means functionally connected with rear steering linkage means, said rear steering linkage means being functionally connected with the rear wheels;
• shift lever means providing a specific selection among a plurality of steering modes, said shift lever means being operable by the vehicle user and being selectively movable among a plurality of operating positions;
• wherein the operating positions include a first operating position for a first steering mode consisted of steerage of front wheels with rear wheels neutral, a second operating position for a second steering mode consisted of steerage of rear wheels with front wheels neutral, a third operating position for a third steering mode consisted of coincidence-phase steerage of front wheels and rear wheels, and a fourth operating position for a fourth steering mode consisted of reverse-phase steerage of front wheels and rear wheels;
• steering shaft means for carrying both the front drive means for controlling turning of front wheels and the rear drive means for simultaneously controlling turning of the rear wheels, said steering shaft means being operably attached to and controlled by both the steering wheel and the shift lever means;
• wherein a front group and a rear group of gear positions are spaced on the steering shaft means;
• the front group including a first, a second, a third and a fourth gear positions to be correlated respectively with the first, the second, the third and the fourth operating positions of the shift lever means;
• the rear group including a fifth, a sixth, a seventh and an eighth gear positions to be correlated respectively with the first, the second, the third and the fourth operating positions of the shift lever means;
• a plurality of gear means specifically disposed on the gear positions of the steering shaft means;
• wherein the first gear position includes at least a gear;
• the second gear position includes no gear;
• the third gear position includes at least a gear;
• the fourth gear position includes at least a gear;
• the fifth gear position includes no gear;
• the sixth gear position includes at least a gear and a reverse idler gear;
• the eighth gear position includes at least a gear and a reverse idler gear;
• and
• joint means incorporated into a connection between the steering wheel and the steering shafting means;
• wherein the vehicle user can operate the shift lever means to move the said joint means and thus to move the steering shaft means;
• wherein when the shift lever means is moved to the first operating position, the steering shaft means will be moved such that the gear at the first gear position engages with the front drive means and no gear at the fifth gear position engages with the rear drive means;
• when the shift lever means is moved to the second operating position, the steering shaft means will be moves such that no gear at the second gear position engages with the front drive means and the gear at the sixth gear position engages with the rear drive means with the reverse idler gear interposed therebetween;
• when the shift lever means is moved to the third operating position, the steering shaft means will be moved such that the gear at the third gear position engages with the front drive means and the gear at the seventh gear position engages with the rear drive means;
• when the shift lever means is moved to the fourth operating position, the steering shaft means will be moved such that the gear at the fourth gear position engages with the front drive means and the gear at the eighth gear position engages with the rear drive means with the reverse idler gear interposed therebetween.