Engine Control Unit Torque Reduction for Gearbox Speed Surge
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vehicles without a clutch sensor experience unpleasant engine speed surges during gearbox ratio changes, as they lack the necessary sensor to immediately cut off fuel injection, leading to abrupt reactions.
Innovation Solution
The engine control unit detects the foot being raised, records the engine speed and engaged gearbox ratio, determines a maximum permissible engine speed, and monitors the current speed to initiate or maintain a transient progressive torque reduction phase, ensuring a controlled speed surge by cutting off injection if the speed exceeds this threshold.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the transient progressive torque reduction phase is activated when the driver requests zero torque, then the abrupt jerked slowing action is prevented, but the engine speed surge occurs during gearbox ratio change
Solution Approach 1:
The patent applies dynamics by making the torque reduction phase adaptive rather than fixed. The control unit dynamically adjusts the torque reduction strategy based on real-time detection of gearbox ratio changes. When a ratio change is detected during the transient progressive torque reduction phase, the system switches to an immediate torque cut-off strategy, thereby adapting the control approach to maintain engine speed stability during critical transitions while preserving smooth deceleration during normal operation.
2Stability of the object's composition
If a clutch sensor is used to detect disengagement state, then the engine speed surge is prevented, but the device complexity and production cost increase
Solution Approach 1:
The patent applies self-service by enabling the engine control unit to detect gearbox ratio changes using existing sensors and data already present in the system. The control unit monitors engine speed, vehicle speed, and throttle position to infer gearbox state changes without requiring additional dedicated sensors. This self-diagnostic capability eliminates the need for extra hardware while maintaining engine speed stability during ratio transitions.
Solution Approach 2:
The patent applies universality by making the engine control unit perform multiple functions: it manages fuel injection, ignition timing, and now also detects gearbox ratio changes to prevent speed surges. The existing control unit is programmed to analyze data from sensors already present in the system (engine speed sensor, vehicle speed sensor, throttle position sensor) to infer gearbox state, thereby using existing hardware for multiple purposes without adding dedicated clutch sensors.
3Stability of the object's composition
If the injection is cut off immediately upon disengagement detection, then the engine speed surge is prevented, but the progressive cut-off strategy is no longer activated
Solution Approach 1:
The patent applies segmentation by dividing the torque cut-off strategy into two distinct segments based on gearbox state: (1) progressive torque reduction for normal deceleration when the gearbox is engaged, and (2) immediate torque cut-off when disengagement or ratio change is detected. The control unit segments the control logic to switch between these two strategies, ensuring smooth deceleration during normal operation while preventing speed surges during critical transitions.
Data Source
AI summary
Method for controlling speed surge of an internal combustion engine of a moving vehicle during a ratio change of a manual gearbox, the vehicle including an engine control unit with a transient progressive torque reduction phase activated when the driver requests zero torque or when the foot is raised, the engine control unit: detects the raised foot and activates the transient progressive torque reduction phase; records engine speed and determines the gearbox ratio engaged when the foot is raised; determines, a maximum permissible engine speed (Nmax) which is greater than the recorded speed (Nlvp) of the raised foot, in accordance with the engine speed recorded and the engaged gearbox ratio; monitors the current speed (Nc) so that if Nc>Nmax, a stop is initiated with immediate effect of the transient progressive torque reduction phase, an if Nc≦Nmax, the transient progressive torque reduction phase is maintained.