Abstract A power-assisted control device for a change-speed transmission mechanism providing a plurality of gear ratios engageable at will, which comprises a gear selector adapted to perform a directed movement of selection and a directed movement of engagement of the gear ratios of said transmission mechanism, a manually operated gear change lever, a servo action device operatively connected to said gear selector, means responsive to said gear change lever for actuating said servo action device, characterized in that there are provided, as a power-assisted control device, a pair of single-acting pneumatic actuators of the cylinder and piston type wherein the pistons acting in opposition on said gear selector, are immersed in the lubricant of the transmission casing with their faces opposite to the pneumatic control chamber of said actuators, each piston aforesaid forming a damping chamber having a fixed wall in the casing, with at least one throttling passage for the lubricant between said casing and said damping chamber.
A power-assisted control device for a change speed transmission mechanism providing a plurality of gear ratios engageable at will, which comprises a gear selector adapted to perform a directed movement of selection and a directed movement of engagement of the gear ratios of said transmission mechanism, a manually operated gear change lever, a servoaction device operatively connected to said gear selector, means responsive to said gear change lever for actuating said servoaction device, characterized in that there are provided, as a power-assisted control device, a pair of single-acting pneumatic actuators of the cylinder and piston type wherein the pistons, acting in opposition on said gear selector, are immersed in the lubricant of the transmission casing with their faces opposite to the pneumatic control chamber of said actuators, each piston aforesaid forming a damping chamber having a fixed wall in the casing, with at least one throttling passage for the lubricant between said casing and said damping chamber.
Claim 2
Dependent Claim
157 words
A power-assisted control device for a change speed transmission mechanism providing a plurality of gear ratios engageable at will, which comprises a gear selector adapted to perform a directed movement of selection and a directed movement of engagement of the gear ratios of said transmission mechanism, a manually operated gear change lever, a servoaction device operatively connected to said gear selector, means responsive to said gear change lever for actuating said servoaction device, characterized in that there are provided, as a power-assisted control device, a pair of single-acting pneumatic actuators of the cylinder and piston type wherein the pistons, acting in opposition on said gear selector, are immersed in the lubricant of the transmission casing with their faces opposite to the pneumatic control chamber of said actuators, each piston aforesaid forming a damping chamber having a fixed wall in the casing, with at least one throttling passage for the lubricant between said casing and said damping chamber.
Claim 3
Dependent Claim
42 words
A power-assisted control device for a change speed transmission mechanism as set forth in claim 1, characterized in that said wall is formed with at least one passage incorporating a nonreturn valve in the direction from said damping chamber to said casing.