Abstract: A multi cone selector in a transmission employs sandwiched cone friction surfaces 19A, 20A and 21A and these are shown in free or unengaged state while the corresponding friction surfaces as numerals 19, 20 and 21 are shown as engaged. This comparative illustration shows the relative positions of the surfaces at different times since the “A” surfaces and the non “A” surfaces are the same circumferential surfaces. The cone selector is used to engage free rotating gear a female part 22 of a multi-cone selector. A hydraulic actuator 23 is received by internal gear case wall 24 formed so as to prevent any radial or axial movement of the actuator itself. A hydraulic coupling, in this case the hydraulic coupling is formed as hydraulic springs or bags illustrated at 26. The crown of hydraulic spring outlet piston is formed so as to clip in a housing of a thrust bearing 29.

Abstract: In a transmission of the constant mesh type a number of gear selectors are driven by using a hydraulic coupling between input and output pistons. The hydraulic coupling functions as a hydraulic spring and force multiplier. A hydraulic actuator (23) is received by internal gear case wall (24) formed so as to prevent any radial or axial movement of the actuator itself. A hydraulic coupling, in this case the hydraulic coupling is formed as hydraulic springs or bags illustrated at (26).