Coupling technology to replace Universal Joints and Lovejoy couplings.
Universal Joint verses Twin Spring Coupling
Twin Spring Coupling features
- Speeds: Up to 7000 rpm
- Peak Torque Largest Size ft lbs (Nm) 300 ft lbs (407) 500ft lbs (678)
- Standard Coupling sizes 1-1/3/8” (25.4-35mm)
- Temperature: -20° to +290°F , (-4° to +140°C)
- Connection: Spline
- Torsionally rigid design at angles less than 10°
- Minimal backlash
- No moving parts
The Universal Joint or U joint coupling has been an industry standard for over 115 years, for engineers looking for a flexible coupling solution for high speed minimal misalignment applications. The Spicer Universal joint was first patented in 1904.
The standard universal joint is made up of 3 components, 2 end yokes and the universal joint itself.
Universal Joint – The joint contains 4 small bearings at the end of each of the cross, these bearings need to be maintained and kept lubricated or they will heat up and seize, requiring replacement meaning time and money, add to that the universal joint design which allows the two attached shafts to work out of alignment. This misalignment means the ball bearings inside the bearings will wear against the outside of the race (groove the ball bearings sit in) leading to the race being enlarged and the ball bearings becoming loose, leading to increase vibration potentially damaging attached equipment or bearing failure.
Yokes – The Yokes allow the two shafts (input/output) to attach to the universal joint. These yokes vary and some have to be welded on to the shaft. The yokes are substantial in size except where they attach to the universal joint, they are only slightly larger to ensure the joint can work at an angle without binding or hitting the propeller joint. This is an area of weakness as this can be an area where cracking can lead to failure, as we have see recently with the Ford Transit van driveline recall. Stress, the universal joint being used at a large angle of misalignment, a moderate blow along the input/output shaft can lead to this kind of cracking.
Twin Spring Coupling one piece design – The downside is it wasn’t able to handle angles before they start to wear the bearings out, and the constant maintenance requirements make it a product that becomes expensive to use.
The Twin Spring coupling dual spring design allows for minimal windup, non-balanced maintenance free coupling solution with the positives of high torque capacity and increased flexibility even at speed.
This means where applications that need torque and misalignment while still working at high speed can now be achieved without resorting to a beam or jaw coupling (which still cannot work at increased angle misalignment.
The Twin Spring coupling contains no internal components that require maintenance so we offer the positives of high torque and misalignment in one coupling without the worry of maintenance.
Twin Spring Coupling has no yokes as its one piece design means its integrated end hubs take the place of the yokes and the industry standard splines mean a common fit to all existing universal joints it replaces.
At low angle misalignment, Twin Spring coupling maintains its torsional rigidity and high speed, it also continues to do so as misalignment continues to increase due to the pivoting central ball bearing which allows torque to transfer through the coupling.