PRESSURE-ACTUATED GEAR SHIFTING DEVICE

摘要

The pressure-actuated gear shifting device intended to gear-boxes, particularly multispeed gear-boxes, comprises a gear shifting lever (2) actuated according to an HH shifting diagram, a control shaft (3) being arranged on a support (1) at hand reach of the driver. Said shaft (3) is axially displaced by means of the gear-lever (2) for the path selection and rotatively for the gear selection. The control shaft (3) is provided with cams (32 to 34) cooperating with valves (11 to 16) which control a pressure fluid. The valves act, via selection (6) and actuation (8) cylinders secured to the gear-box (5), on a shifting shaft (9). Thereby the desire shift couplings are actuated and the driver is informed as to the operation state of the gear-box. The shifting shaft (9) is also provided with safety valves (91) which authorize actuation motions only in the neutral position. Multistage cams (93, 94) cooperating with 3/2 way valves comprised of radial displacement pistons fixe the two position shift cylinder (8) in a medial position. The driver also receives via a piston member (170) an indication as to a favorable speed or path as a function of running parameters such as the vehicle speed.