Power Tool Dual Battery Voltage Difference Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional dual battery power tools experience power loss and overheating due to voltage differences between batteries, and fail to recharge back electromotive force, leading to inefficient operation and potential damage.
Innovation Solution
Incorporating a control device and switching members that detect voltage differences between batteries and control power flow to prevent overcharging and provide a path for back electromotive force discharge, allowing both batteries to supply power efficiently to the motor module when voltage differences are within a predetermined range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If diodes are used to connect batteries to motor, then overcharging prevention is achieved, but power loss occurs due to forward bias
Solution Approach 1:
The patent changes the electrical parameter state by using switching members that can transition between conductive and non-conductive states based on voltage difference detection. When voltage difference exceeds the threshold, switching members open the circuit to prevent overcharging; when within threshold, they close the circuit to enable power transmission with minimal loss, thus dynamically adjusting the system state to resolve the contradiction between overcharging prevention and power loss reduction
Solution Approach 2:
The control device acts as an intermediary between the batteries and motor module, detecting voltage differences and controlling switching members to regulate power flow. This intermediary mechanism enables intelligent decision-making to prevent overcharging while minimizing power loss through controlled conduction paths
2Reliability
If diodes are used to connect batteries to motor, then circuit protection is provided, but overheating occurs during high power operation
Solution Approach 1:
The patent dynamically changes the resistance parameter of the circuit path by using switching members with lower on-resistance compared to diodes. During high power operation, the switching members remain in low-resistance conductive state, reducing I²R heating and preventing overheating while maintaining circuit protection through voltage difference monitoring
3Reliability
If diodes are used in the circuit, then unidirectional current flow is ensured, but back electromotive force cannot be recharged to battery
Solution Approach 1:
The patent introduces dynamic controllability to the circuit through switching members that can change their conduction state based on real-time voltage difference detection. This dynamic mechanism allows the circuit to adaptively permit back electromotive force flow to recharge batteries when appropriate, while maintaining unidirectional control when needed, thus resolving the contradiction between current direction control and energy recovery
Solution Approach 2:
The patent converts the previously harmful back electromotive force (which caused heating and energy loss) into a beneficial resource for battery recharging. By using switching members controlled by voltage difference detection, the system captures and redirects the back electromotive force to recharge batteries, transforming energy waste into energy recovery
4Loss of energy
If switching members are used instead of diodes, then power loss is reduced, but device complexity increases
Solution Approach 1:
The control device performs multiple functions: detecting voltage differences, controlling switching members, preventing overcharging, and enabling back electromotive force recovery. By consolidating these functions into a single control unit, the patent manages device complexity while achieving superior power loss reduction compared to passive diode-based systems
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
Reduces power loss and prevents overcharging, while enabling the recharge of back electromotive force, thereby enhancing the operational efficiency and longevity of the power tool by minimizing heat generation and damage.
Implementation Method 1
the first control end is controllable to conduct or cut off the first end and the second end
Implementation Method 2
a counter electromotive force generated when the motor M stops running cannot be recharged to the battery B due to the diode D being cut off in the reverse biased
Data Source
AI summary
A power tool includes a first connecting port, a second connecting port, a motor module, a first switching member, a second switching member, and a control device. The first switching member is connected between the motor module and the first connecting port. The second switching member is connected between the motor module and the second connecting port. The control device is connected to the first switching member and the second switching member. A control method thereof includes: switch on the first switching member and the second switching member when the control device determines that both the first connecting port and the second connecting port are respectively connected to a battery and a difference between voltages inputted to the first connecting port and the second connecting port is smaller than a predetermined voltage difference, allowing two batteries to supply power to the motor module at the same time.