Decoupled Cooling System for Battery-Powered Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery-powered screwing devices face heat dissipation challenges, particularly at low speeds and when plastic housings limit thermal conductivity, leading to reduced duty cycles and increased risk of tool shutdown due to overheating.
Innovation Solution
A battery-powered tool device with a decoupled cooling system that can control cooling capacity independently of the drive device's rotational speed, featuring a ventilation system with air inlet and outlet openings and a flow channel to efficiently cool the motor, control unit, and battery, allowing effective heat dissipation even at low speeds and when the tool is not in use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the tool operates at low speeds or under load, then high thermal energy must be dissipated, but the fan wheel cannot provide sufficient cooling since it is coupled to the drive device speed
Solution Approach 1:
The cooling function is extracted from the drive device by providing a separate drive mechanism (motor) for the fan wheel. This allows the cooling system to operate independently from the drive device speed, enabling effective heat dissipation even when the drive device operates at low speeds or is stationary.
Solution Approach 2:
The motor that drives the fan wheel serves multiple functions: it can operate during high-load conditions to provide active cooling, and can continue running after the drive device stops to dissipate residual heat. This multi-functional approach ensures comprehensive thermal management across all operating conditions.
2Temperature
If the tool is used for final tightening at low speeds, then most heat is generated immediately before the motor is switched off, but the cooling system cannot effectively dissipate this heat
Solution Approach 1:
The control device activates the fan wheel drive motor in advance during high-load operations and continues running it after the drive device stops. This preliminary and extended cooling action ensures that heat generated during final tightening is dissipated before the tool shuts down, preventing overheating-induced shutdowns.
Solution Approach 2:
The cooling system maintains continuous operation through the transition from active cooling during high-load phases to residual heat dissipation after shutdown. The fan wheel continues rotating for a period after the drive device stops, ensuring uninterrupted thermal management throughout the entire operational cycle.
3Ease of manufacture
If plastic housing is used, then the tool is easier to manufacture and lighter, but heat dissipation to the outside is limited due to plastic being an insulator
Solution Approach 1:
The fan wheel and airflow system act as intermediaries to overcome the insulating property of the plastic housing. By actively moving air through the housing structure, the system creates forced convection that bypasses the thermal insulation barrier, enabling effective heat dissipation while maintaining the advantages of plastic construction.
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 solution extends the tool's duty cycle, maintains a consistent temperature, increases reliability, and reduces the need for frequent tool replacements, enhancing power density and operational efficiency while preventing overheating-induced shutdowns.
Implementation Method 1
the cooling device has a ventilation device which generates an air flow at least through areas of the tool device
Implementation Method 2
a first cooling device in order to cool the drive device and/or the control device
Data Source
Figure 1
AI summary
An electrically operated tool device (100) with a rotatable tool head (30), with an electric motor drive unit (4) for driving the tool head (30), with a control unit (8) for controlling the electric motor drive unit (4), and with a power supply unit (9) for supplying at least the drive unit (4) with electrical energy, wherein the tool device (1) has a first cooling unit (19) for cooling the drive unit (4) and/or the control unit (8). According to the invention, the cooling capacity of the cooling unit (19) is controllable independently of the rotational speed of the electric motor drive unit (4).