Shift Range Control Device Abnormality Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shift range control devices face challenges in seamlessly switching shift ranges when abnormalities occur in one of the multiple systems driving a motor, leading to potential lock-ups or unintended operations due to interference between systems.
Innovation Solution
The implementation of a shift range control device with dual control units and motor drivers that monitor for abnormalities and temporarily disconnect affected systems to prevent interference, allowing for smooth operation and range switching by prioritizing the normal system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple systems drive a motor for shift range control, then reliability is improved through redundancy, but interference between systems may cause lock-up or unintended operation
Solution Approach 1:
The patent extracts and isolates the abnormal system from the motor control loop by detecting abnormalities in detection values from sensors or motor current, then stopping the abnormal system's motor driver while allowing the normal system to continue controlling the motor. This separation prevents the abnormal system from interfering with the normal system's control operations.
Solution Approach 2:
The control unit acts as an intermediary that mediates between multiple drive systems and the motor. It receives detection values from both systems, determines which system is abnormal, and selectively enables or disables each system's motor driver accordingly, preventing direct interference between competing control signals.
2Device complexity
If one microcomputer controls motor driving, then device complexity is reduced, but no abnormality detection capability exists
Solution Approach 1:
The control unit performs multiple functions: it controls both the first and second motor drivers, processes detection values from multiple sensors, determines abnormalities in either system, and manages the switching between normal and abnormal systems. This multi-functionality provides abnormality detection without requiring separate dedicated detection hardware.
Solution Approach 2:
The patent merges the control functions for both drive systems into a single control unit that also handles abnormality detection and system switching. By combining control and monitoring functions in one unit, the patent avoids the complexity of multiple independent microcomputers while maintaining comprehensive system oversight.
Data Source
AI summary
A shift range control device that switches a shift range by controlling driving of a motor includes a plurality of control units and a plurality of motor drivers. The plurality of control units respectively have an energization control unit for controlling energization to the motor and an abnormality monitor unit for performing abnormality monitoring. The energization control unit turns off energization of the own system in a state of temporary abnormality before determining a decisive abnormality when abnormality affecting the other system is detected in the own system while driving the motor by the plurality of systems, and the abnormality monitor unit determines whether a state of abnormality is the temporary abnormality or the decisive abnormality after turning off energization of the own system.