PEX Pipe Expander with Auto-Rotation and Clutch Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tools for expanding PEX tubing lack efficiency and convenience in expanding multiple joints simultaneously, leading to increased installation time and effort in building construction.
Innovation Solution
A multi-segment expansion tool with an auto-rotation feature, powered by a motor and planetary gear transmission, utilizing a radial cam and index cam mechanism to drive a jaw assembly that expands and secures PEX tubing by crimping, with a clutch ring and rotation ring system to prevent damage in case of jamming, and a handle with a rubber-like grip for user comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a manual expansion tool is used for PEX tubing, then the tool structure is simple, but the installation time increases and productivity decreases
Solution Approach 1:
The patent replaces manual mechanical operation with an electric motor-driven system. The motor (15) powers a planetary gear transmission (16) that automatically rotates the jaw assembly (30), eliminating the need for manual rotation while maintaining mechanical expansion functionality. This substitution directly increases installation speed while the automated mechanism manages the complexity through standardized components.
2Productivity
If a single-joint expansion tool is used, then the tool design is simple, but the time required for expanding multiple joints increases
Solution Approach 1:
The patent implements continuous useful action through the auto-rotation feature. The planetary gear transmission (16) continuously rotates the jaw assembly (30) through multiple joints without requiring the user to reposition or reset the tool between joints. This continuous operation significantly reduces installation time while the multi-joint capability increases productivity by processing multiple connections in sequence.
3Reliability
If the jaw assembly rotates during expansion, then the expansion is more effective, but the risk of damage from jamming increases
Solution Approach 1:
The patent applies beforehand cushioning through the clutch ring (24C) and rotation ring (24R) mechanism with sawtooth-shaped teeth (24S). This design anticipates potential jamming during rotation and provides a predetermined failure mode where the teeth disengage to prevent damage. The spring (25S) maintains engagement under normal conditions while allowing automatic release when jamming occurs, protecting the PEX tubing and tool components.
4Ease of operation
If a motor-driven auto-rotation system is implemented, then the ease of operation improves, but the device complexity increases
Solution Approach 1:
The patent implements self-service through the automatic rotation system. Once the motor (15) is activated, the planetary gear transmission (16) automatically rotates the jaw assembly (30) without requiring user intervention for positioning or manual cranking. The clutch mechanism (24C, 24R) with spring (25S) provides self-regulating protection that engages and disengages automatically based on operational conditions, reducing user effort while managing complexity through automated functions.
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 tool significantly reduces installation time by efficiently expanding multiple PEX tubing joints with minimal user effort, ensuring secure connections and preventing damage during the expansion process.
Implementation Method 1
a four-stage planetary gear transmission 16, which has an output spindle 16S
Implementation Method 2
jaws rotating/expanding mechanism 20 includes a radial cam 21 and an index cam 22
Implementation Method 3
A wedge 24, which moves in a reciprocating motion
Implementation Method 4
A spring 25S may abut an end of wedge 24 and roller assembly 25R, thus biasing roller assembly 25R towards radial cam 21
Implementation Method 5
Housing 11 may be overmolded with a rubber-like material 110 for better grip
Data Source
Figure 1~2
Figure 3A~3C
Figure 4~6B
AI summary
A tool operable to expand an end of a pipe, such as PEX pipe, has a jaw assembly with jaws movable between a closed position and an expanded position and rotatable about a longitudinal axis. A motor drives an output spindle (16S), which in turn drives a radial cam (21). A wedge (24) is movable by the radial cam in a reciprocating motion along the axis, causing the wedge to move between a first position where the jaws are in the closed position and a second position where the jaws are in the expanded position. A rotating ring is mounted on the wedge and connected to the jaws. The rotating ring is driven by the output spindle for rotating the jaws about the axis.