Power Tool Switch Rotary Bearing for Ferromagnetic Dust Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The magnetic switch actuator in hand-operated power tools tends to attract ferromagnetic dust, chips, and other debris, leading to tool malfunction and rendering the power tool unusable.
Innovation Solution
Incorporating a rotary bearing at the through opening of the switch housing, where the transmission element is rotatably mounted, allows for a design that prevents environmental contaminants, such as ferromagnetic dust, from entering the switch chamber and interfering with the switch actuator.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a magnetic switch actuator is used in the switch chamber, then the switch can effectively control the drive motor, but ferromagnetic dust and chips are attracted to the actuator causing tool malfunction
Solution Approach 1:
The switch housing is divided into a sealed switch chamber and an external actuation mechanism. The transmission element acts as a barrier that segments the internal magnetic actuator from external ferromagnetic contaminants, allowing the magnetic field to pass through while blocking physical contamination.
Solution Approach 2:
The transmission element serves as an intermediary component between the external actuating element and the internal magnetic switch actuator. It transmits mechanical motion while the rotary bearing provides a sealed interface that prevents ferromagnetic dust from reaching the sensitive magnetic components.
2Object-affected harmful factors
If the switch chamber is completely sealed, then dust contamination is prevented, but the transmission element cannot pass through to connect the actuating element
Solution Approach 1:
The rotary bearing acts as a flexible rotational interface that allows the transmission element to pass through the sealed switch housing wall. It provides a rotating seal that maintains the sealed environment while enabling mechanical transmission, similar to how flexible membranes allow passage while maintaining seals.
Solution Approach 2:
The rotary bearing is extracted as a separate functional component that handles the sealing and rotation function. This allows the transmission element to rotate through the housing wall without compromising the sealed environment, separating the sealing function from the transmission function.
3Object-affected harmful factors
If a rotary bearing is added at the through opening, then ferromagnetic dust is sealed out, but the device complexity increases
Solution Approach 1:
The rotary bearing performs multiple functions simultaneously: it seals the switch chamber against ferromagnetic dust, allows rotational movement of the transmission element, and provides a mounting interface for the transmission element. This multi-functionality reduces the need for additional separate components.
Solution Approach 2:
The rotary bearing combines the sealing function and the rotational transmission function into a single integrated component. Rather than having separate seals and bearing structures, the design merges these functions into one element that accomplishes both tasks.
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 rotary bearing effectively seals the switch chamber from external dust and debris, ensuring reliable operation of the hand-operated power tool by preventing magnetic contamination of the switch actuator.
Implementation Method 1
the rotary bearing effectively seals the switch chamber from external dust and debris, ensuring reliable operation of the hand-operated power tool by preventing magnetic contamination of the switch actuator
Implementation Method 2
The magnetic switch actuator in hand-operated power tools tends to attract ferromagnetic dust, chips, and other debris
Data Source
AI summary
A switch (30) for a hand-held power tool (10) or as a component of a hand-held power tool (10), which has an electric drive motor (16) that can be switched by the switch (30). The switch (30) has a switch housing (33) with a switch chamber (35) in which a switch actuator (75) that can be moved between at least two switch positions (ML, MR) is arranged in order to actuate an electric switch element, said switch actuator being kinetically coupled, by means of a transmission element (70), to a switch (30) actuation element (32), which is arranged outside the switch housing (33) and can be moved between at least two actuation positions (R, L), wherein the transmission element (70) passes through a through-opening (54) on a wall of the switch housing (33) such that the switch actuator (75) can be moved by moving the actuation element (32) in order to actuate the switch element (24). A rotary bearing (77) is arranged in the through-opening (54), the transmission element (70) being rotatably mounted on the rotary bearing about a rotational axis (D).