Abstract

A variator (10) has a race formed from an input disc (12) and an output disc (14) and a plurality of rollers (22) located between the input and output discs, for transmitting drive therebetween. Either the input disc (12) and output disc (14) or the rollers (22), but not both, has a sintered powdered metal rolling surface.

IPC Classes  ?

• F16H 15/38 - Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line with concave friction surface, e.g. a hollow toroid surface with two members B having hollow toroid surfaces opposite to each other, the member or members A being adjustably mounted between the surfaces
• F16H 15/32 - Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line
• F16H 15/00 - Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by friction between rotary members

Abstract

A transmission is disclosed for a wheeled vehicle. The transmission has a rotary input (14) to be driven by a rotary power source, e.g. an internal combustion engine. It has a rotary output (16) 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 (20) 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.

IPC Classes  ?

• B60K 17/04 - Arrangement or mounting of transmissions in vehicles characterised by arrangement, location or kind of gearing
• F16H 57/02 - GearboxesMounting gearing therein
• F16H 37/08 - Combinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings with a plurality of driving or driven shaftsCombinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings with arrangements for dividing torque between two or more intermediate shafts with differential gearing
• B60K 17/00 - Arrangement or mounting of transmissions in vehicles
• F16H 63/30 - Constructional features of the final output mechanisms
• B60T 1/00 - Arrangements of braking elements, i.e. of those parts where braking effect occurs

Abstract

Variators that include a damped roller control part.

IPC Classes  ?

• F16H 15/38 - Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line with concave friction surface, e.g. a hollow toroid surface with two members B having hollow toroid surfaces opposite to each other, the member or members A being adjustably mounted between the surfaces
• F16H 37/02 - Combinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings
• F16H 15/00 - Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by friction between rotary members

Abstract

The use of powdered metal components in a variator is disclosed. Traction fluid of various sorts may be used in the variators, not just high performance synthetics or application specific lubricants.

IPC Classes  ?

• F16H 55/32 - Friction members

Abstract

A transmission arrangement is disclosed which comprises first and second variators (166, 169) each of which comprises an input race (150, 154) and an output race (152, 156). A plurality of rollers (276, 278) is arranged to run upon the input and output races to transfer drive from one to the other. The races are mounted for rotation about a common axis and the inclination of the first variator's rollers is variable independently of the inclination of the second variator's rollers, so that the two rollers are able to provide independently and continuously variable drive ratios. To provide traction between the rollers and races, a biasing device (216, 217) applies an axial force to one of the races, urging the rollers and races into engagement with each other. Each variator is provided with a shunt gear for providing forward, reverse and g eared neutral ratios, and to couple the variator input to the shunt gear a coupling member (160) passes through the outer variator races.

IPC Classes  ?

• F16H 37/08 - Combinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings with a plurality of driving or driven shaftsCombinations of mechanical gearings, not provided for in groups comprising essentially only toothed or friction gearings with arrangements for dividing torque between two or more intermediate shafts with differential gearing
• F16H 15/38 - Gearings providing a continuous range of gear ratios in which a member A of uniform effective diameter mounted on a shaft may co-operate with different parts of a member B in which the member B has a curved friction surface formed as a surface of a body of revolution generated by a curve which is neither a circular arc centered on its axis of revolution nor a straight line with concave friction surface, e.g. a hollow toroid surface with two members B having hollow toroid surfaces opposite to each other, the member or members A being adjustably mounted between the surfaces