Transmission System

A method for shifting gear ratios of a transmission system comprising:

• providing a first floating gear rotationally mounted upon a first shaft and a floating gear activation system for controlling torque transfer between the first floating gear and the first shaft, the gear activation system comprising a first device having a friction interface for frictional engagement with a friction interface disposed on a first side of the first floating gear, and a second device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the first floating gear, the second side opposing the first side;
• providing a second floating gear rotationally mounted upon the first shaft and the gear activation system comprising a third device having a friction interface for frictional engagement with a friction interface disposed on a first side of the second floating gear, and a fourth device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the second floating gear, the second side opposing the first side;
• engaging the friction interface of the third device with the friction interface of the second floating gear by sliding the third device along the first shaft;
• disengaging the locking interface of the second device from the locking interface of the first floating gear by sliding the second device along the first shaft;
• engaging the locking interface of the fourth device with the locking interface of the second floating gear by sliding the fourth device along the first shaft.
• disengaging the friction interface of the third device with the friction interface of the second floating gear by sliding the third device along the first shaft.

A transmission system comprising at least two floating gears rotationally mounted upon a first shaft, and at least two further gears mounted upon at least one further shaft said at least one further gear being coupled to a respective one of the at least two floating gear on the first shaft, the transmission system comprising a floating gear activation system for controlling torque transfer between each of the at least two floating gears and the first shaft, the gear activation system comprising a first device having a friction interface for frictional engagement with a friction interface disposed on a first side of each of the at least two floating gears, and a second device having a locking interface for an interpositional engagement with a locking interface disposed on a second side, opposing the first side, of each of the at least two floating gears, whereby the floating gear is rotationally coupleable to the first shaft by the friction interface and/or the locking interface, the transmission system comprising a control unit coupled to a sensor for measuring a parameter indicative of the torque on the first shaft the sensor positioned between the a first floating gear of the at least two floating gears and a second floating gear of the at least two floating gears, wherein the control unit receives data from the sensor indicating which of the first or second floating gears is transferring torque from the first shaft to the at least one further shaft.

A method for engaging a locking interface of a transmission system comprising:

• providing a transmission system comprising first shaft having a first floating gear mounted thereon, and a first activator for synchronising rotation of the first floating gear with the first shaft, the first floating gear having a first locking interface for interpositional engagement with a second locking interface provided upon the first activator, the first and second locking interfaces forming a locking device, the activator being slidingly mounted upon the first shaft for movement in an axial direction a second activator for synchronising rotation of the first floating gear with the first shaft, the first floating gear having a first friction interface for frictional engagement with a second friction interface provided upon the second activator, the first and second locking interfaces forming a friction device, and the transmissions system comprising at least one sensor for providing data indicative of the axial position of the activator;
• engaging the friction device to synchronise rotation of the first floating gear with the first shaft;
• sliding the activator along the first shaft until the first interface contacts the second interface;
• receiving data from the sensor;
• determining whether the activator has moved to a position in which the first interface is in interpositional engagement with the second interface;
• if the first locking interface is in interpositional engagement with the second locking interface;
• disengaging the frictional device;
• or
• if the first interface is not in interpositional engagement with the second interface;
• reducing the frictional engagement between the first and second friction interfaces;
• whereby
• rotating the first floating gear with respect to the first shaft such that the first locking interface rotates with respect to the second locking interface;
• resliding the activator along the first shaft until the first locking interface is in interpositional engagement with the second locking interface.

A device for a transmission system comprising:

• a first side;
• a second side, opposing the first side;
• a friction interface for frictional engagement with a friction interface of a first gear;
• a locking interface for an interpositional engagement with a locking interface of a second gear;
• wherein the friction interface is disposed on the first side and the locking interface is disposed on the second side.

A method for shifting gear ratios of a transmission system comprising:

• providing a first floating gear rotationally mounted upon a first shaft and a floating gear activation system for controlling torque transfer between the first floating gear and the first shaft, the gear activation system comprising a first device having a friction interface for frictional engagement with a friction interface disposed on a first side of the first floating gear, and a second device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the first floating gear, the second side opposing the first side;
• providing a second floating gear rotationally mounted upon the first shaft and the gear activation system comprising a third device having a friction interface for frictional engagement with a friction interface disposed on a first side of the second floating gear, and a fourth device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the second floating gear, the second side opposing the first side;
• engaging the friction interface of the first device with the friction interface of the first floating gear by sliding the first device along the first shaft;
• disengaging the locking interface of the second device from the locking interface of the first floating gear by sliding the second device along the first shaft;
• engaging the friction interface of the third device with the friction interface of the second floating gear by sliding the third device along the first shaft;
• disengaging the friction interface of the first device with the friction interface of the first floating gear by sliding the first device along the first shaft;
• engaging the locking interface of the fourth device with the locking interface of the second floating gear by sliding the fourth device along the first shaft.

A method for holding a vehicle on a hill comprising:

• providing a first floating gear rotationally mounted upon a first shaft and a floating gear activation system for controlling torque transfer between the first floating gear and the first shaft, the gear activation system comprising a first device having a friction interface for frictional engagement with a friction interface disposed on a first side of the first floating gear, and a second device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the first floating gear, the second side opposing the first side;
• providing at least one further floating gear mounted upon the first shaft, the or each at least one further floating gear having a friction interface for frictional engagement with a respective friction interface of at least one further device;
• wherein the method comprises;
• frictionally engaging the friction interface of the first floating gear with the first device and/or engaging the locking interface of the first floating with the second device;
• and simultaneously,
• engaging one or more of the friction interfaces of the at least one further floating gear with the respective friction interface of the at least one further device.

A method for shifting gear ratios of a transmission system comprising:

• providing a first floating gear rotationally mounted upon a first shaft and a floating gear activation system for controlling torque transfer between the first floating gear and the first shaft, the gear activation system comprising a first device having a friction interface for frictional engagement with a friction interface disposed on a first side of the first floating gear, and a second device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the first floating gear, the second side opposing the first side;
• providing a second floating gear rotationally mounted upon a second shaft, the second floating gear being coupled to the first shaft by a further gear mounted on the first shaft and the gear activation system comprising a third device having a friction interface for frictional engagement with a friction interface disposed on a first side of the second floating gear, and a fourth device having a locking interface for interpositional engagement with a locking interface disposed on a second side of the second floating gear, the second side opposing the first side;
• engaging the friction interface of the first device with the friction interface of the first floating gear by sliding the first device along the first shaft;
• disengaging the locking interface of the second device from the locking interface of the first floating gear by sliding the second device along the first shaft;
• engaging the friction interface of the third device with the friction interface of the second floating gear by sliding the third device along the second shaft;
• disengaging the friction interface of the first device with the friction interface of the first floating gear by sliding the first device along the first shaft;
• engaging the locking interface of the fourth device with the locking interface of the second floating gear by sliding the fourth device along the second shaft.

A method for adapting the torque transfer function of a transmission system comprising:

• engaging a friction interface of first activator with a friction interface of the gear under test, disengaging a locking interface of a second activator from a locking interface of the gear under test;
• reducing the force applied by the friction interface of the first activator to the friction interface of the gear under test, whereby introducing a predefined degree of slip;
• recording a control parameter of the transmission system which produces the predefined degree of slip;
• receiving a parameter indicative of torque value delivered to the transmission system;
• interrogating a database to obtain a stored value of the control parameter corresponding to the value of the parameter indicative of torque value delivered to the transmission system;
• comparing the stored value of the control parameter with the recorded value of the control parameter;
• updating the data base with the recorded value of the control parameter if different to the stored values;
• increasing the pressure between the friction interface of the first activator and the friction interface of the gear under test so as to synchronise the gear under test with the shaft upon which it is mounted;
• engaging a locking interface of the gear under test by activating the second activator to interpose the locking interface of the second activator with the locking interface of the gear under test;
• disengaging the friction interface of the first activator from the friction interface of the gear under test.