Safety in entry-control systems

Stay safer with the appropriate worm gearbox

Approaching the sixty years of foundation, Varvel SpA can count on a great experience in designing and producing worm and bevel helical gearboxes for automated gates and barriers control in collaboration with a number of specialized manufacturers.fig1_Varvel

The whole design is performed by Varvel’s internal R & D Department starting from customized specifications and using a state-of-the-art software for gear design.

Automated gates are usually made of a single shutter running along a rack railway on the ground and its running needs a long and narrow track where the gate slides during opening and closing. Shutter’s weight and height are key elements to consider when selecting the right gearbox size.

For such requirements, Varvel has developed a series of appropriate worm gearboxes, with wormshaft and wormgear special materials and specific lubrication for intermittent use that is the case in sliding gates.

These solutions may include some important options: the built-in lock/unlock device of the RT worm gearbox, available from size 28 to 110 in all the gear ratios. Unlocking and locking are activated manually through lever or control wheel, and remotely by electromagnet.

In case of rolling shutters, driving needs lifting safety measures to prevent the uncontrolled shutter fall, i.e. a tooth gear break. For that type of applications, Varvel designed another built-in device allowing an active safety mechanism. In fact, that “parachute device” blocks mechanically and instantaneously the shutter, solving that danger possibility completely.

Automatic barriers are the ideal entry system to control vehicle and pedestrian transit in parking areas, private passages, building accesses and highway barriers with a high traffic levels. Usage and beam span are key elements in right model and size selection of which bevel/helical gearboxes are recommended for gate driving.

These reducers, because of the barrier pedestal – very limited in internal space – need to have reduced sizes and to be mounted in line with the electric motor. Precisely matching such needs, Varvel’s RO series, in-line bevel/helical gearboxes, solve the above issues.

Usually, in those applications the final reducer gear ratio is not particularly high, generally between 1/30 and 1/50. Therefore Varvel has personalised the bevel helical reducers adding only two stages of gear ratio instead of the usual three-stage scheme. A customisation that allows to keep yielding and performances high, while reducing production costs.