Starter Pinion Gear Retraction Noise Control
Solution Overview
Problem
The existing starter systems generate noise during the retraction of the pinion gear to its initial position due to collisions with limiting members, which is not effectively mitigated by current technologies.
Innovation Solution
A starter system configuration that includes a control unit to manage the current through the solenoid after disengagement from the ring gear, reducing the urging force and minimizing the impact of the pinion gear's retraction by passing a predetermined current through the solenoid before the pinion gear reaches its initial position, thus reducing noise generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the pinion gear is allowed to retract to the initial position using only the urging member (spring), then the structure is simple, but noise is generated due to collision with the limiting member
Solution Approach 1:
The control unit applies a preliminary opposing force by energizing the solenoid in reverse direction before the pinion gear reaches the limiting member. This preliminary anti-action reduces the retraction speed and prevents collision, thereby eliminating noise without requiring additional mechanical damping components.
Solution Approach 2:
The system changes the electrical parameter (solenoid current) dynamically during the retraction process. By applying current in the reverse direction at a predetermined timing, the magnetic field parameter changes to generate an opposing force that controls the pinion gear's retraction speed and prevents impact collision.
2Object-generated harmful factors
If a damping mechanism is added to reduce collision impact, then noise is reduced, but device complexity increases
Solution Approach 1:
The patent replaces the mechanical damping mechanism with an electromagnetic control system. Instead of using physical dampers or shock absorbers, the control unit uses timed electrical current through the solenoid to generate magnetic forces that control the pinion gear's retraction, substituting mechanical complexity with electrical control.
Solution Approach 2:
The control unit acts as an intermediary between the urging member and the pinion gear. It receives signals about the pinion gear's position and timing, then applies appropriate electrical current to the solenoid to modulate the magnetic force, thereby mediating the interaction between the spring and the pinion gear to prevent collision.
3Object-generated harmful factors
If the solenoid current is continuously applied during retraction, then the pinion gear retraction is controlled, but energy consumption increases
Solution Approach 1:
The control unit applies solenoid current periodically rather than continuously. It energizes the solenoid in reverse direction only during the critical period when the pinion gear approaches the limiting member, and stops current application when the pinion gear is safely retracted. This periodic action reduces energy consumption while maintaining effective collision prevention.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively minimizes noise and impact during the retraction of the pinion gear by controlling the solenoid current, enhancing the operational quietness and reducing potential damage from collisions with limiting members.
Implementation Method 1
a pushing member that pushes a pinion gear toward a ring gear connected to an output shaft of the engine, using an electromagnetic force generated by current being passed through a solenoid
Implementation Method 2
an urging member that urges the pinion gear in a direction opposite to the direction into which the pinion gear is pushed out by the pushing member
Data Source
AI summary
In a starter, current is passed through a solenoid to use the generated electromagnetic force when pushing a pinion gear toward a ring gear, so that the ring gear is engaged with the pinion gear. For this purpose, the starter includes an electromagnetic solenoid, a spring for urging the pinion gear in a direction opposite to that of the electromagnetic solenoid, a connecting member connected to the pinion gear, a stopper for limiting movement of the connecting member to a predetermined position. Being urged by the spring, the pinion gear is disengaged from the ring gear, and the connecting member is retracted to a predetermined position. The starter includes a control circuit that implements control of passing a predetermined current through the solenoid after the disengagement but before retraction of the connecting member to the predetermined position.