Process for controlling gear shifting in a cycle, and corresponding system and components

A system for controlling gear shifting in a transmission of a cycle in which said at least one gear wheel has at least one given angular position in which the shifting of said element for transmitting motion is facilitated, comprising at least one gear wheel on which is engaged a transmission element that performs transmission of motion as a result of its advance in a pre-determined direction;

• the gear shifting being carried out by changing the position of engagement of said transmission member with respect to said at least one gear wheel, the said system comprising:
• at least one sensor for detecting the movement and corresponding direction of movement of said motion-transmitting element and for generating a respective signal;
• a control unit for controlling, starting from said respective signal, the change of the position of said element for transmitting motion with respect to said at least one gear wheel when said signal indicates that said element for transmitting motion is moving in said pre-determined direction;
• at least one switch for selective activation of said at least one sensor according to a command for changing the position of said element for transmitting motion with respect to said at least one gear wheel;
• said at least one sensor generates a corresponding signal indicating the position of said at least one gear wheel;
• and
• said control unit being configured for preventing shifting of said at least one gear wheel when the latter is not in an angular position corresponding to said at least one given angular position, and then allowing change of position of said element when said at least one gear wheel is forwardly rotated to the next angular position corresponding to said at least one given angular position.

A process for controlling gear shifting in the transmission of a cycle comprising at least one gear which engages a transmission element that performs transmission of motion as a result of its advancement in a pre-determined direction;

• the gear shifting being carried out by changing the position of engagement of said transmission element with respect to said at least one gear, the process comprising the steps of:
• detecting the movement and the corresponding direction of movement of said element for transmitting motion;
• controlling change of position of said element for transmitting motion with respect to said at least one gear when said element for transmitting motion is moving in said pre-determined direction,
• providing sensor means for detecting at least one quantity comprised in the group consisting of:
• the angular position of said at least one gear;
• and
• the movement of said element for transmitting motion and the corresponding direction of movement;
• and, selectively activating said sensor means according to a command request for changing the position of said element for transmitting motion with respect to said at least one gear.

A system for controlling gear shifting in a transmission of a cycle having at least one gear wheel on which is engaged a transmission element that performs transmission of motion as a result of its advance in a pre-determined direction, the gear shifting being carried out by changing the position of engagement of said transmission member with respect to said at least one gear wheel, said system comprising:

• at least one sensor for detecting the movement and corresponding direction of movement of said motion-transmitting element and for generating a respective signal;
• a control unit for controlling, starting from said respective signal, the change of the position of said element for transmitting motion with respect to said at least one gear wheel when said signal indicates that said element for transmitting motion is moving in said pre-determined direction;
• and
• at least one switch for selective activation of said at least one sensor according to a command for changing the position of said element for transmitting motion with respect to said at least one gear wheel.

A method for controlling gear shifting on a bicycle having a plurality of gears with at least one gear including teeth with a sequence of differentiated geometries which define facilitating portions on said gear, comprising the steps of:

• a) detecting a processing signal representative of a shift command;
• b) detecting rotation of the at least one gear;
• c) detecting the direction of rotation of the at least one gear;
• d) detecting the angular position of the at least one gear;
• e) comparing the angular position of the at least one gear to the angular position of the facilitating portions of the at least one gear;
• f) shifting the chain from the at least one gear to another gear if the direction of rotation is indicative of forward pedaling, and if the detected angular position of the at least one gear corresponds to one of said facilitating portions,
• wherein the steps (b)-(e) are performed only after detection of an affirmative shift command.