Digital Logic Circuit for Indirect Secondary Gear Position Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods are ineffective in determining the relative position of a secondary gear without direct measurement, as it is unfeasible to provide a phonic wheel or sensor to detect the secondary gear's position when it is rotatably connected to a primary gear.
Innovation Solution
A system comprising a phonic wheel fixed to the primary gear, a sensor to detect the phonic wheel's teeth, and a digital logic circuit that generates pulses corresponding to the primary and secondary gear revolutions, allowing the determination of the secondary gear's position based on the primary gear's tooth pulses and rotation rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a phonic wheel or sensor is provided to directly detect the secondary gear's position, then the measurement precision of the secondary gear position is improved, but the device complexity increases and it becomes unfeasible when the secondary gear is rotatably connected to the primary gear
Solution Approach 1:
The patent uses the primary gear as an intermediary to indirectly measure the secondary gear's position. By attaching a phonic wheel to the primary gear and using a sensor to detect its teeth, the system generates primary gear tooth pulses that are then processed through digital logic circuits to calculate the secondary gear's position based on the known gear ratio, avoiding the need to directly attach sensors to the secondary gear
Solution Approach 2:
The patent creates a virtual representation of the secondary gear's position by generating secondary gear evolution signals through digital logic processing of primary gear tooth pulses. This virtual copy allows the system to determine secondary gear position without physical direct measurement, reducing hardware complexity while maintaining measurement capability
2Reliability
If direct measurement of the secondary gear position is implemented, then the reliability of position detection is improved, but it becomes unfeasible due to the mechanical connection constraints between primary and secondary gears
Solution Approach 1:
The primary gear serves as a mediator that can be easily accessed and instrumented with a phonic wheel and sensor. This intermediary approach allows reliable position detection to be implemented on the primary gear, which is mechanically accessible, while the secondary gear's position is derived through calculation based on the established gear relationship
3Adaptability or versatility
If multiple secondary gears are rotatably connected to the primary gear, then the gear assembly functionality is improved, but it becomes unfeasible to provide sensors for each secondary gear
Solution Approach 1:
The patent implements a universal measurement approach where a single sensor system on the primary gear serves multiple secondary gears simultaneously. The digital logic circuit processes primary gear tooth pulses to generate evolution signals for multiple secondary gears based on their respective gear ratios, allowing one sensor system to provide position information for multiple gears without requiring individual sensors for each
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 accurate determination of the secondary gear's position without direct measurement, reducing errors due to mechanical variations and shaft speed variations, and effectively calculating the relative position of multiple gears based on the primary gear's rotation information.
Implementation Method 1
Example sensors include magnetic speed pickup sensors, optic sensors, hall-effect sensors, and eddy-current sensors
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
A system (100) for determining a relative position of a secondary gear (12) includes a gear assembly (10) including a phonic wheel (13) fixed to a primary gear (11) and a secondary gear (12) rotatably engaged to the first gear, a sensor (20) configured to output a signal upon detecting a tooth (14) of the phonic wheel, and a digital logic circuit (30) configured to detect a revolution of the phonic wheel, to generate a primary gear tooth pulse at intervals corresponding to intervals of teeth (15) of the primary gear based on the detected revolution of the phonic wheel, and to generate a secondary gear revolution signal at an interval corresponding to a revolution of the secondary gear (12) based on the primary gear tooth pulse.