Eaton Corporation

Torotrak (development) Limited

Torotrak Limited

David Ian Cox

Leslie Kendrick Robinson

A transmission is disclosed for a wheeled vehicle. The transmission has a rotary input () to be driven by a rotary power source, e.g. an internal combustion engine. It has a rotary output () for driving a vehicle wheel. A transmission unit is coupled between the rotary input and the rotary output to transfer drive between them at a speed ratio which is continuously variable through a range which includes both negative ratios (providing a reversal of rotational direction between the rotary input and the rotary output), positive ratios (in which the rotary input and the rotary output rotate in the same direction), and a geared neutral ratio, in which the rotary output is stationary. In accordance with the invention, the transmission further comprises a brake () for braking the rotary output. The brake is provided with a control arrangement adapted to apply it when the speed ratio is set to the geared neutral ratio and to release the brake as the speed ratio is adjusted away from the geared neutral ratio.

Continuously variable transmission with brake

A pin-type synchronizer mechanism (86) with self-energizing ramps is configured to provide self-energizing forces for reducing an operator applied shift force (F.sub.o) and/or shift time. The self-energizing forces are provided by self-energizing ramp surfaces (29e,29f,29g,29h) and (111a, 111b,111c, 111d) respectively, formed in external splines (29) of a shaft 28 and in internal teeth (111) extending radially inward from a shift flange (110). The ramp surfaces provide an additive axial force (F.sub.a) applied to friction rings (114,116) via shift flange blocker surfaces (110d,110e) reacting respectively against pin blocker surfaces (118c, 118d). The shift flange carries improved pre-energizer and neutral position centering assemblies (120) including pre-energizer plungers (124) and neutral position plungers (126) respectively for axially retaining pins (118) and friction rings (114,116) in a neutral position relative to flange (110) and for neutral positioning flange (110) relative to recesses (128)in shaft (28).

Growing community of inventors

Wigan, United Kingdom

David Ian Cox