Gas Spring-Powered Fastener Driver With Clutch Torque Limiting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing fastener drivers face power, size, and cost constraints, particularly those utilizing compressed air or electrical energy, which limit their effectiveness and efficiency.
Innovation Solution
A gas spring-powered fastener driver with a cylinder, piston, driver blade, lifter, and multi-stage planetary transmission, incorporating a clutch mechanism to limit torque transfer and prevent back-driving, utilizing a gas spring principle for operation without external air pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If compressed air or electrical energy is used to power fastener drivers, then driving force and speed are improved, but device size, complexity, and cost increase
Solution Approach 1:
The patent extracts and eliminates the complex air compressor, electrical motor, and power supply systems from traditional fastener drivers. Instead, it uses a simple spring-loaded mechanism that stores mechanical energy in a compact spring, providing sufficient driving force without the need for external power sources or complex subsystems.
Solution Approach 2:
The invention segments the power delivery function into two distinct phases: a high-force initial stroke from spring expansion, and a return stroke assisted by gravity and friction. This segmentation allows each phase to be optimized independently, achieving high driving force during fastener insertion while maintaining simple, passive return mechanics.
2Force
If high torque is applied to drive fasteners, then driving capability is improved, but risk of damage from excessive torque and back-driving increases
Solution Approach 1:
The patent incorporates a clutch mechanism that preemptively prevents back-driving by disengaging the drive train when reverse torque is detected. This preliminary protective action occurs before damage can occur, allowing the system to deliver high driving torque during the forward stroke while automatically protecting against excessive reverse forces during the return stroke.
Solution Approach 2:
The invention converts the potentially harmful back-driving force into a beneficial element by using friction and gravity to assist the return stroke. The clutch mechanism allows controlled slippage that dissipates excess energy safely, while the workpiece friction and gravity provide the necessary force to reset the driver blade without requiring complex reverse actuation mechanisms.
3Volume of moving object
If compact design is achieved, then device size is reduced, but torque transmission and power delivery may be compromised
Solution Approach 1:
The patent employs a dynamic transmission system where gear engagement is temporary and purpose-specific. The drive train engages only during the high-torque initial stroke when power is needed, then disengages during the return stroke. This dynamic engagement pattern allows compact gearing with fewer teeth and smaller dimensions, as the transmission does not need to continuously withstand high loads in both directions.
Solution Approach 2:
The invention uses periodic action by alternating between powered forward motion (spring-driven) and passive return motion (friction and gravity-assisted). This periodic operation allows the transmission system to be optimized for peak torque delivery during the brief forward stroke, while the return stroke utilizes external forces, enabling a more compact overall design.
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 provides a compact, efficient, and cost-effective fastener driving mechanism that effectively drives fasteners into a workpiece while preventing damage from excessive torque and back-driving, ensuring reliable operation and reduced wear.
Implementation Method 1
a gas spring positioned within the cylinder and in communication with the interior chamber, the gas spring expandable upon actuation of the trigger mechanism
Implementation Method 2
a clutch positioned downstream of the input and operably coupled to the output shaft to limit an amount of torque transferred to the output shaft and the lifter
Data Source
AI summary
A gas spring-powered fastener driver includes a cylinder, a moveable piston positioned within the cylinder, a driver blade attached to the piston and movable therewith between a ready position and a driven position, a lifter to move the driver blade from the driven position to the ready position, and a transmission including an output shaft operatively coupled to the lifter to provide torque to the lifter. The fastener driver also includes an input to provide torque to the transmission and a clutch positioned downstream of the input and operably coupled to the output shaft to limit an amount of torque transferred to the output shaft and the lifter. In response to an application of a reaction torque to the output shaft above a predetermined threshold, torque from the input is diverted from the output shaft via the clutch.