Axial Slip and Torque Overload Protection
Understanding axial slip and torque overload is critical in ensuring the lifetime and safety of components and equipment.
There are, of course, conventional engineering solutions for protection of the motor, gear teeth and other drive components during a torque overload condition, but they are usually costly, complicated or both. An electronic approach to solving torque overload problems could be to use a current sensor to monitor near stall current conditions. Quite a complex solution, this method can be expensive and adds considerable weight to the final product. An alternative mechanical approach could be to use a clutch; however, this method is also expensive, weighty and increases the size of the overall assembly.
Building on the knowledge and experience gained in several successful designs already deployed within the automotive industry, Saint-Gobain Performance Plastics' engineers have created an in-line torque slip solution. Quick and easy to assemble, the new design helps reduce weight and save space of the overall assembly – two key advantages.
The RENCOL® tolerance ring sits between two mating components. Tubes slip at a predetermined force level controlled by design characteristics of the tolerance ring. The RENCOL® tolerance ring acts as an inexpensive slip element, controlling forces in all sorts of situations: vehicle crash -- steering columns, bumpers, wiper systems; and adjustment of axial components -- telescopic columns or handles (seats)
Tolerance Ring Selection for Axial Slip
Flanged rings are HV rings with flanged ends (protruding rim that surrounds the circumference of the material) used for axial load control or limiter. Examples of use would be steering column collapse mechanisms.
HV rings (housing variable) are "open" in free state when installed inside the bore ring, making it self retaining. The ring sits in the housing with waves on the inside to be compressed by the outer diameter of the mating part.
Axial Slip -- RENCOL® Tolerance Ring Benefits
Ease of assembly
- Space saving inline solution
Reduced overall system weight
- Reduce number of overall components
- Design can improve NVH characteristics of assembly
- Compensation for thermal expansion
- Confirmation of axial force during assembly process
- Able to absorb large component tolerances +/0.10mm
- Simplify design complexity
The RENCOL® tolerance ring sits between two mating components. Application slips at predetermined torque level, controlled by design characteristics of the tolerance ring. The RENCOL® tolerance ring acts as an inexpensive slip clutch, preventing damage via torque overload situations to expensive mechanisms and fragile components such as gear boxes and gears, electric motors, and steering columns.
RENCOL® Tolerance Ring Selection for Overload Protection
SV rings (shaft variable) are free-state diameter rings, smaller than shaft diameter. When mounted, rings are self-retaining on shaft. The ring sits on shaft with waves on the outside to be compressed by housing bore.
SVD rings (shaft variable duplex) are single piece rings with two sets of waves. They show increased performance over the SV ring. SVD rings allow use of single, wide rings instead of two rings in separate grooves which offers cost savings.
Torque Overload -- RENCOL® Tolerance Ring Benefits
- Proven solution satisfying EC Commission Directive 95/56/EC (Steering Column Anti-Theft)
- Ease of assembly
- Cost reduction in line
- Space saving and reduced weight
- Single generic global component design
- Complexity (number of components)
- Protects other components
- Zero backlash
- Instant reaction time (<10 ms)
- Compensation for thermal expansion
» For more details on products protecting against axial slip or torque overload, please visit Sales and Support for regional contact information, or Email Us directly with your enquiry.