Electronic Spindle Lock Control for Bit Change Torque Holding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power tools require a mechanical spindle lock to inhibit rotation of the drivetrain when tightening or loosening chuck jaws, which adds length, cost, and complexity to the tool.
Innovation Solution
Implementing an electronic spindle lock system that uses a controller and motor to resist rotation by detecting user input and applying counter torque, eliminating the need for a mechanical spindle lock.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a mechanical spindle lock is added to inhibit rotation of the drivetrain, then the reliability of the power tool during bit changes is improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent replaces the mechanical spindle lock system with an electronic control system that uses the motor controller to detect when the trigger is released and automatically applies reverse torque to lock the spindle. This substitution eliminates separate mechanical locking components while achieving the same functional goal through electronic control and motor torque management.
Solution Approach 2:
The motor controller is given multiple functions: it controls motor operation during normal use, detects trigger release status, and automatically implements spindle locking by applying reverse torque. This multi-functionality eliminates the need for dedicated spindle lock mechanisms, reducing overall device complexity while maintaining reliability.
2Reliability
If a mechanical spindle lock is added to inhibit rotation of the drivetrain, then the reliability of the power tool during bit changes is improved, but the manufacturing cost increases
Solution Approach 1:
The patent replaces the mechanical spindle lock system with an electronic control system that uses the motor controller to detect when the trigger is released and automatically applies reverse torque to lock the spindle. This substitution eliminates separate mechanical locking components while achieving the same functional goal through electronic control and motor torque management.
Solution Approach 2:
The spindle locking function is merged with the existing motor control system. The same controller that manages motor operation during tool use now also handles spindle locking by detecting trigger release and applying appropriate reverse torque, eliminating the need for separate manufacturing of dedicated locking mechanisms.
3Reliability
If the motor is controlled to rotate in the second direction to maintain a static rotation position, then the spindle lock effectiveness is improved, but the energy consumption increases
Solution Approach 1:
The electronic spindle lock operates periodically rather than continuously. The controller monitors trigger status and only activates the reverse torque when the trigger is released, indicating a bit change operation. During normal operation, the lock remains inactive, minimizing energy consumption while maintaining effectiveness when needed.
Solution Approach 2:
The system uses the existing motor and controller infrastructure to provide the locking function, rather than requiring separate power sources or additional energy-intensive mechanisms. The motor itself provides the reverse torque needed for locking, utilizing already-available power and control resources.
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 electronic spindle lock reduces the overall design complexity and cost of power tools while maintaining effective control over the drivetrain during bit changes.
Implementation Method 1
The motor is rotated in the second direction to maintain a static rotation position
Data Source
AI summary
Electronic spindle lock for a power tool. One embodiment provides a power tool including a housing, a bit receiving portion provided on the housing for receiving a power tool bit, a motor within the housing configured to rotate the bit receiving portion, and a controller coupled to the motor. The controller is configured to enter an electronic spindle lock mode, and detect rotation of the bit receiving portion in a first direction. The controller is also configured to control motor to rotate in a second direction in response to detecting rotation of the bit receiving portion in the first direction.