{{ post.title }}
글 편집
{{ post.author.name }}
Posted on
| Version | {{ post.target_version }} | Product |
{{ product.name }}
|
|---|---|---|---|
| Tutorial/Manual | {{ post.tutorial.upload_filename }} | Attached File | {{ post.file.upload_filename }} |
Improved torque wrench design and the precision of its torque indicator
Product: Torque Wrench
Analysis Goal: Design a precise torque scale that captures the nonlinear behavior of the torque wrench
A torque wrench is a wrench that allows the user to apply a specific amount of torque to fasteners like bolts and nuts. Some torque wrenches have torque-limiting switches that prevent the wrench from applying more than a user-specified amount of torque. Using experimentation to verify that a torque-limiting switch accurately meets its specifications is difficult. Furthermore, designing it using physical experimentation is costly and time-consuming. In this case study, an existing torque wrench design was modified, which required that the wrench’s torque indicator be modified as well. Simulation was used to redesign the indicator and improve its accuracy. Therefore, the indicator was modified using simulation instead of experiment. Because the applied torque is nonlinear due to dynamic behavior, deformation, and contact between various parts, it could not be reproduced with traditional FEA software. Therefore, RecurDyn, a Flexible Multi Body Dynamics (MFBD) software, was used to design the torque wrench, and it was possible to design an accurate torque wrench with precise torque indicator.
◆ Process
① Modeled the torque wrench’s primary coil spring using flexible beam elements and all other parts using rigid bodies.
② Defined contacts between the flexible beam and rigid bodies.
③ Tested various coil diameters and material properties for the
primary spring.
④ Determined the precise configuration of the torque indicator
through the torque values obtained from the simulations.
◆ Key Technologies for Analysis
- MFBD modeling that allows for simultaneous use of rigid and flexible bodies
- Contact between rigid bodies and flexible bodies
- Efficient parametric modeling for testing various beam diameters and material properties
- Robust solver technology that accurately reproduces the nonlinear behavior of the torque wrench
◆ Toolkits
- RecurDyn/Professional
- RecurDyn/FFlex
◆ Customer Challenges
- For increased torque range, need to change spring free length and coil diameter
- Nonlinear motion needed to be evaluated to accurately predict the torque
- Need to improve the design with reasonable time and cost
◆ Solutions
- Precise torque calculation using MFBD technology which can simulate systems with both rigid and flexible bodies that make contact with each other.
- Modeling simplification and time-saving through beam and parametric modeling
- Simulation of various designs using an intuitive user interface
◆ Outcomes
- RecurDyn was able to accurately recreate the behavior of the existing design.
- RecurDyn validated the nonlinear behavior and created confidence in using non-uniform torque scale on the indicator.
- Time and cost reduction through quantitative evaluation of various possible designs
- Simulation results provided additional guidance for further design improvements for the torque wrench.
◆ Other Applications
-
Analyzing the design of locking plier using MBD for ANSYS (RecurDyn)
