Paddle Switch Over-Travel Absorption Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power tools with brushless electric motors require larger power switches that are not compatible with the smaller current paths in more compact tools, leading to inefficiencies and potential damage from excessive travel distance in activating the on/off switches.
Innovation Solution
A paddle switch with a switch contact lever and biasing member that absorbs the over-travel distance, ensuring the on/off switch is activated within a smaller angular range, preventing damage and maintaining functionality with smaller, high-voltage capable switches.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a conventional paddle switch is used with a smaller on/off switch in compact power tools, then the power tool becomes more compact, but the excessive travel distance of the paddle switch causes damage to the smaller on/off switch
Solution Approach 1:
A switch contact lever is introduced as an intermediary component between the paddle switch and the on/off switch. The lever has a first engagement feature that receives the paddle switch and a second engagement feature that actuates the on/off switch. This intermediary mechanism allows the paddle switch's larger travel distance to be decoupled from the on/off switch's required actuation distance, preventing damage while maintaining compact tool design.
Solution Approach 2:
The switch actuation mechanism is segmented into separate functional components: the paddle switch for user input, the switch contact lever for transmission and adaptation, and the on/off switch for circuit control. This segmentation allows each component to be optimized independently - the paddle switch for ergonomic travel and the on/off switch for precise, limited-travel actuation - resolving the contradiction between compact size and durability.
2Volume of moving object
If a smaller on/off switch is used in compact power tools, then the power tool size is reduced, but the switch can only carry smaller current which limits power delivery capability
Solution Approach 1:
The electrical current path is segmented into two separate paths: a high-current path that bypasses the small on/off switch (carrying motor current) and a low-current control path that goes through the small on/off switch (carrying only control signal current). This allows the use of a compact switch without compromising the power delivery capability of the tool, as the main current flow does not pass through the limited-capacity switch.
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 efficient and safe operation of compact power tools by ensuring the on/off switch is activated within a controlled angular range, reducing wear and tear on the switch components while accommodating smaller switch sizes.
Implementation Method 1
a biasing member (224) between the paddle switch (200) and the switch contact lever (222) to absorb an over-travel distance of the paddle switch (200)
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
A power tool (10) is provided including a housing (12), a motor (16) disposed within the housing, an on/off switch (26) having a contact tip (26a) disposed within the housing for activating the motor, a paddle switch (200) coupled to the housing via a pivot member (204) and having a paddle trigger (202) engageable by a user, a switch contact lever (222) disposed in selectable engagement with the contact tip of the on/off switch to activate or deactivate the on/off switch, and a biasing member (224) disposed between the switch contact lever and the paddle switch to absorb a travel distance of the paddle trigger with respect to the switch contact lever.