Engine Starter Pinion Engagement via One-Way Clutch Dynamics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional engine starters cannot immediately restart an engine during the engine stop process due to the inability to engage the pinion with the ring gear until the engine is fully stopped, leading to potential delays and inefficiencies in CO2 reduction strategies.
Innovation Solution
An engine starting apparatus comprising an electric motor, a one-way clutch, pinion pushing means, and current switching means, which allows the pinion to be pushed towards the ring gear when the ring gear's revolutions are higher, enabling instantaneous synchronization and engagement using a one-way clutch with idling torque lower than the ring gear's rotational torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the engine is restarted using a conventional starter, then the engine can be restarted after fully stopped, but the engine cannot be restarted during the engine stop process (from deceleration to complete stop)
Solution Approach 1:
The patent makes the pinion axially movable relative to the ring gear, allowing the pinion to dynamically adjust its position. The pinion can be pushed axially to engage with the ring gear even when the ring gear is rotating at low speed or stationary, enabling restart during the engine stop process rather than requiring complete engine stop first
Solution Approach 2:
The patent introduces a one-way clutch as an intermediary mechanism between the pinion and the ring gear. This one-way clutch allows the pinion to be pushed axially to engage the ring gear while preventing reverse rotation, serving as a mediator that enables engagement during the stop process without requiring complete engine stop
2Ease of operation
If the pinion is pushed toward the ring gear during rotation, then engagement can be achieved, but synchronization of revolutions requires complex motor control
Solution Approach 1:
The patent replaces complex electronic motor revolution control with a simple mechanical one-way clutch mechanism. Instead of using motors and control systems to synchronize revolutions, the one-way clutch mechanically allows the pinion to be pushed axially to engage the ring gear, eliminating the need for complex control electronics
Solution Approach 2:
The one-way clutch automatically handles the engagement process without requiring external control. When the pinion is pushed axially, the one-way clutch allows engagement with the ring gear and automatically prevents reverse rotation, making the system self-regulating without complex control
3Reliability
If a one-way clutch with low idling torque is used, then engagement during rotation is enabled, but the clutch must withstand the ring gear's rotational torque
Solution Approach 1:
The one-way clutch is designed with dynamic torque characteristics: low idling torque when the engine is rotating (allowing easy engagement) and high load-bearing capacity when the engine stops (withstanding ring gear torque). The clutch transitions between these states dynamically based on engine operation
Solution Approach 2:
The one-way clutch's torque parameter changes based on operating conditions. During engine rotation, the clutch allows low torque passage for smooth engagement. When the engine stops and the ring gear applies torque, the clutch's structural design enables it to withstand this higher torque while maintaining the low idling torque characteristic during operation
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
Enables quick and reliable engagement of the pinion with the ring gear during the engine stop process, reducing the need for expensive motor revolution control drivers and enhancing the reliability and efficiency of engine restarts, particularly in idle stop systems.
Implementation Method 1
a one-way clutch (18) that is helical-spline-fitted to the outer periphery surface of the output shaft (6)... the one-way clutch having an idling torque smaller than a torque of the ring gear that tries to turn the pinion
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In an engine starting apparatus, together with a one-way clutch (18), a pinion (19) is pushed toward a ring gear (3) of an engine mounted in a vehicle. The one-way clutch has an idling torque smaller than a torque of the ring gear that tries to turn the pinion when the pinion is pushed to the ring gear. By control means (2), pinion pushing means (8) is enabled to operate when i) the revolution speed of the ring gear is larger than a revolution speed of the pinion and ii) a relative revolution speed between the revolution speed of the ring gear and the revolution speed of the pinion is a desired value.