The Huco Dynatork MS worm gearbox with integral torque limiter is useful for safeguarding machinery and operatives by stopping rotation of the low-speed shaft whenever the stall torque exceeds the calibrated value of the internal torque limiter. Of course, in the event of a power cut, this safety gearbox effectively locks and, in the majority of applications, this is an appropriate consequence. For others, however, it is a disadvantage.
Take, for example, a powered door. Under normal circumstances the MS gearbox would ensure safe operation, but a loss of power could leave the door stuck open or closed. For applications such as this, Huco Dynatork is introducing the MRV50.LS safety worm gear box with disengaging torque limiter. A disengaging lever provides a manual override so that, in this application example, the door can still be operated until power is restored.
Huco Dynatork claims that there is no other comparable product available. The alternatives are disengaging couplings or electromagnetic clutches, but neither has the simplicity nor the cost-efficiency of the MRV50.LS.
How it works
The built-in torque limiter comprises a symmetrical cone on the output shaft acting against a hollow cone on the worm wheel, all rotating in an oil bath. This gives precise adjustment and consistency in the slipping point during torque overload. The low contact pressure between the conical hub and the worm wheel of the gearbox make constant adjustment unnecessary during the life of the product. Thanks to use of quality materials and the inclusion of an oil bath, component wear is greatly minimised.
Disengaging models are available for single-, three-phase and DC operation, with 40-80mm centres. The power range is 0.09-3kW.