Impact Tool Output Position Sensing for Torque and Blow Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power tools struggle to consistently deliver a desired output characteristic, such as torque, without the use of a torque transducer, and lack accurate impact counting for modes like blow counting and angular distance control.
Innovation Solution
A power tool with an output position sensor and a controller that monitors the anvil position to detect impacts and adjust motor operation based on impact thresholds, enabling modes like blow counting, angular distance, and constant energy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a torque transducer is used to achieve consistent torque output, then torque control precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent replaces the mechanical torque transducer with an output position sensor that monitors the angular position of the anvil. The controller detects impacts by monitoring changes in anvil position and uses this information to control motor operation, thereby achieving torque control without the complex mechanical torque sensing system.
Solution Approach 2:
The patent introduces an intermediary measurement approach by using output position to indirectly infer torque and impact events. Instead of directly measuring torque, the system measures anvil position changes caused by impacts and uses this positional data to control torque output through motor adjustment.
2Device complexity
If impact counting is implemented without direct anvil position monitoring, then device complexity is reduced, but measurement precision of impact events deteriorates
Solution Approach 1:
The patent replaces complex mechanical impact sensors with an output position sensor that electronically monitors anvil position. The controller detects impacts by identifying sudden changes in anvil angular position, providing accurate impact counting without complex mechanical sensing mechanisms.
Solution Approach 2:
The system implements feedback by continuously monitoring anvil position and using this information to detect impact events. The controller receives real-time position data, processes it to identify impacts, and uses this feedback to control motor operation and maintain precise impact counting.
Data Source
AI summary
A power tool including a motor and an impact mechanism. The impact mechanism is coupled to the motor and includes a hammer driven by the motor, and an anvil positioned at a nose of the power tool, and configured to receive an impact from the hammer. The power tool also includes a sensor assembly positioned at the nose of the power tool, and an electronic processor. The sensor assembly includes an output position sensor configured to generate an output signal indicative of a position of the hammer or the anvil. The electronic processor is coupled to the output position sensor and to the motor, and is configured to operate the motor based on the output signal from the output position sensor.