Clamp-On Cord Current Sensing for Dust Collector Motor Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dust collection systems require users to disconnect power tools from the power source and connect them to a special-purpose socket, adding cost and inconvenience, and limiting current handling capacity.
Innovation Solution
A dust collection system that uses a clamp sensor to measure current flow in the power tool's cord without the need for a special-purpose socket, allowing the system to be actuated when current is detected, regardless of the power tool's connection to a separate electrical outlet.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a special-purpose socket is used to detect current flow, then current measurement capability is achieved, but device complexity and cost increase
Solution Approach 1:
The patent replaces the mechanical/electrical connection system (special-purpose socket requiring physical disconnection and reconnection) with a magnetic field-based sensing system. The clamp sensor detects current flow through the power cord by sensing the magnetic field generated by the current, eliminating the need for mechanical intervention or special sockets.
Solution Approach 2:
The patent introduces a magnetic field as an intermediary between the current flow and the detection system. Instead of directly measuring current through electrical contact, the system uses the magnetic field generated by the current as a mediator that can be sensed remotely by the clamp sensor, enabling non-contact current detection.
2Measurement precision
If a special-purpose socket is used to detect current flow, then current measurement capability is achieved, but ease of operation deteriorates
Solution Approach 1:
The patent replaces the mechanical/electrical connection system (special-purpose socket requiring physical disconnection and reconnection) with a magnetic field-based sensing system. The clamp sensor detects current flow through the power cord by sensing the magnetic field generated by the current, eliminating the need for mechanical intervention or special sockets.
3Power
If power handling requirements are based on vacuum power plus power tool power, then sufficient power capacity is achieved, but adaptability deteriorates
Solution Approach 1:
The patent makes the dust collection system universally adaptable to any power tool by using external current sensing on the power cord. The system can detect and respond to current flow from any power tool regardless of its specific power requirements, allowing the vacuum to be activated and sized appropriately for any tool without being dedicated to a specific power tool model.
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 cost-effective and convenient dust collection by allowing the system to be used with standard power tools, without the need for additional hardware, and can handle higher current capacities than traditional systems.
Implementation Method 1
The electromagnetic element senses current flow in the cord
Data Source
AI summary
A dust collection system includes a sensor body, a selection circuit, a detection circuit, and a motor control circuit. The sensor body detachably encircles a cord supplying power to a power tool. The cord includes a neutral conductor and a hot conductor. The sensor body houses sensors that, in response to current flow through the cord, generate sensor signals. The selection circuit generates a positive output signal in response to the sensor signals and generates a negative output signal in response to the sensor signals. The detection circuit generates a current detection signal in response to a comparison of the positive and negative output signals with a threshold. The motor control circuit selectively turns on a motor of the dust collection system in response to the current detection signal.