Adjustable Wrench Worm Gear Speed and Self-Locking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing adjustable wrenches face issues such as slow jaw movement in single-threaded structures and inadequate tightening duration along with easy loosening in double-threaded structures.
Innovation Solution
The adjustable wrench incorporates a worm with thread teeth having multiple helices and a lead angle not greater than the self-locking angle, combined with an elastic member and a rack mechanism, to enhance jaw movement speed and prevent skidding or returning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single-threaded structure is used, then the worm tightens firmly and does not come loose easily, but the jaw moves relatively slowly and the worm can withstand relatively small torque
Solution Approach 1:
The worm thread is divided into multiple helices (at least two) instead of a single continuous thread. This segmentation allows the worm to maintain self-locking capability while increasing the lead angle, thereby improving jaw movement speed and torque capacity without sacrificing tightening firmness
2Speed
If a double-threaded structure is used, then the jaw moves rapidly and the worm can withstand large torque, but the tightening duration is inadequate and the structure is easy to loosen
Solution Approach 1:
The lead angle of the worm thread is optimized to be within a specific range (5°-15°) to balance self-locking capability and jaw movement speed. By controlling the lead angle parameter, the design achieves both rapid jaw movement and adequate tightening duration without easy loosening
3Speed
If the lead angle is increased to improve jaw movement speed, then the jaw moves faster, but the self-locking capability deteriorates and the structure becomes prone to skidding and returning
Solution Approach 1:
The lead angle is precisely controlled within the optimal range of 5°-15°, which balances self-locking capability and jaw movement speed. This parameter optimization ensures that the worm maintains sufficient self-locking to prevent skidding and returning while achieving fast jaw movement
Solution Approach 2:
The worm is made of material with specific friction characteristics (self-locking angle greater than lead angle), creating a composite system where the material properties complement the geometric design to achieve both speed and self-locking
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
This configuration allows for faster jaw movement while maintaining effective self-locking, preventing skidding and returning, and improving the overall torque handling capacity.
Implementation Method 1
A screw thread of the worm gear is provided with at least two spiral lines
Implementation Method 2
the lead angle of the worm is not greater than a self-locking angle, wherein the self-locking angle corresponds to the material of the worm
Implementation Method 3
an elastic member disposed between one side, along an axis, of the worm and an inner side surface of the through hole
Implementation Method 4
a rack is disposed on the second jaw, and the rack is provided with fine teeth capable of meshing with the thread teeth
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
The present application discloses an adjustable wrench, comprising a wrench body, a second jaw and an adjustment mechanism, the wrench body comprising a first jaw, a neck and a handle, wherein the first jaw is a front end of the wrench body, and the neck is located between the first jaw and the handle; the first jaw is disposed opposite the second jaw to form a holding space for holding an object; the neck is provided with a through hole, the adjustment mechanism is disposed in the through hole, and the second jaw is movably connected to the neck of the wrench body by the adjustment mechanism; and the adjustment mechanism is used to adjust the movement of the second jaw relative to the first jaw. According to the adjustable wrench disclosed in the present application, a jaw can move relatively fast and can also be effectively prevented from skidding or returning.