Gear selection and engagement device for a motor vehicle transmission

A gear selection and engagement device for pairing axially movable gears with axially fixed gears in a motor vehicle transmission so as to form a gear pair having a predetermined transmission ratio, comprising:

• (a) a transmission case;
• (b) a shaft displaceably and rotatably mounted in said transmission case;
• (c) a manually operable control means connected to said shaft for controllably displacing said shaft along and rotating said shaft about a longitudinal axis;
• (d) a plurality of hubs rotatably and axially displaceably mounted on said shaft, each of said hubs having a pair of control forks integrally connected thereto;
• (e) a first set of teeth projecting radially from said shaft in an axially spaced relationship such that each of said hubs is arranged between two adjacent teeth of said first set, said first set of teeth being axially and circumferentially fixed relative to said shaft;
• and
• (f) a second set of teeth projecting radially from said shaft in an axially spaced relationship such that each of said hubs is arranged between two adjacent teeth of said second set, said second set of teeth being axially slidable and circumferentially fixed relative to said shaft and axially fixed relative to said transmission case,
• wherein each of said hubs has at least one pair of grooves extending axially from respective endfaces of said respective hub, each of said grooves being formed to receive a corresponding one of said teeth, said grooves being arranged at predetermined positions along the circumference of each hub such that when one of said grooves of one of said hubs is aligned with a corresponding one of said second set of teeth in response to rotation of said shaft, one of said grooves of each hub other than said one hub is aligned with a corresponding one of said first set of teeth,
• wherein when said one groove of said one hub is aligned with said corresponding one of said second set of teeth, none of said grooves of said hubs other than said one hub are aligned with a corresponding one of said second set of teeth, and
• wherein said control means comprises a first bushing integrally connected to said shaft and coaxial therewith, said first bushing having an axial groove for receiving said second key, a control rod displaceable along and rotatable about an axis substantially perpendicular to said longitudinal axis of said shaft, and a second bushing integrally connected to said control rod and operatively coupled to said first bushing such that said first and second bushings are relatively rotatable about a first axis substantially parallel to said longitudinal axis and a second axis substantially parallel to said axis about which said control rod is rotatable.