Patent assignee · GB · COMPANY

Torotrak (Development) Limited

76Patents
32Active
76Granted
41Portfolio score

Filing activity: Sep 2, 1988 → Jul 3, 2014 · 26 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US5401221A Transmission of the toroidal-race, rolling-traction type having a mixer and a reducer epicyclic type gearing with clutches brakes Mechanical Engineering; Lighting; Heating 172 Expired
US5564998A Continuously-variable-ratio-transmissions Mechanical Engineering; Lighting; Heating 152 Expired
US8142323B2 Continuously variable transmission Mechanical Engineering; Lighting; Heating 140 Active
US5766105A Continuously variable transmission capable of torque control Mechanical Engineering; Lighting; Heating 104 Expired
US5895337A Continuously-variable-ratios transmissions Mechanical Engineering; Lighting; Heating 82 Expired
US8924111B2 Electronic controller for a continuously variable transmission and a method of control of a continuously variable transmission Mechanical Engineering; Lighting; Heating 54 Active
US5643121A Continuously-variable-ratio transmissions Mechanical Engineering; Lighting; Heating 45 Expired
US5090951A Hydraulic control circuits for continuously-variable-ratio transmissions Mechanical Engineering; Lighting; Heating 39 Expired
US4922788A Continuously variable transmission Mechanical Engineering; Lighting; Heating 37 Expired
US5453061A Continuously-variable ratio transmission of the toroidal race rolling traction type Mechanical Engineering; Lighting; Heating 36 Expired
US5395292A Transmissions of the toroidal-race rolling-traction type Mechanical Engineering; Lighting; Heating 34 Expired
US7491149B2 Fluid supply arrangement for a rolling-traction continuously variable ratio transmission unit Mechanical Engineering; Lighting; Heating 33 Expired
US5938557A CVT Control System Mechanical Engineering; Lighting; Heating 32 Expired
US5242337A Continuously-variable-ratio transmissions of the toroidal-race rolling-traction type Emerging Cross-Sectional Technologies 31 Expired
US7563194B2 Control method and controller for a motor vehicle drive train Performing Operations; Transporting 31 Expired
US5667456A Continuously-variable-ratio transmission having an improved starting arrangement Mechanical Engineering; Lighting; Heating 31 Expired
US7407459B2 Continuously variable ratio transmission system Mechanical Engineering; Lighting; Heating 30 Expired
US5564993A Continously-variable-ratio transmission of the toroidal-race rolling-traction type Mechanical Engineering; Lighting; Heating 30 Expired
US7160226B2 Continuously variable transmission and method of operation thereof Mechanical Engineering; Lighting; Heating 30 Expired
US6030310A Variator control system Mechanical Engineering; Lighting; Heating 29 Expired
US5423727A Transmission of the toroidal-race rolling-traction type Mechanical Engineering; Lighting; Heating 29 Expired
US5971885A Roller assembly Mechanical Engineering; Lighting; Heating 28 Expired
US6626793B1 Hydraulic control circuit for a continuously-variable-transmission Mechanical Engineering; Lighting; Heating 27 Expired
US6979276B2 Control system and method for a continuously variable transmission Mechanical Engineering; Lighting; Heating 27 Expired
US5217418A Drivelines for wheeled vehicles Mechanical Engineering; Lighting; Heating 26 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.