Electrokinetica The Electro-mechanical Museum

Evans AC passenger lift

What was it?

This was a lift serving five floors. Automatic control with a single push at each landing. Traction hoist driven by two induction motors. Yes, two motors; a fast one for running and a slow one for levelling, built into a single frame and called the ‘Bull Super Tandem.’ The high speed motor has a wound rotor and starts with external rotor resistance cut out in steps by contactors. The low speed motor has 30 poles and is only used when the car approaches a landing. The controller is fully electromechanical and uses 150-volt DC doughnut-coil contactors for the main controller and small open-frame relays for the floor controller. Clockwork timers and other interesting gubbins included.

What went wrong?

It’s a rather unfortunate tale. The plant was to be recovered from a building due for demolition. The recovery started out well; the demolition contractors saw the notice we had previously left on the plant stating that it was wanted, and phoned to invite us down to make preparations for its removal. Dan, Lucien and Colin managed to get the machine dismantled and the parts winched down out of the motor room into a safe area on the top floor without incident, ready for demolition to begin. The controller was likewise flat-packed and lowered. We had to return with a demolition breaker to free the bed from its concrete plinth, but left it in situ as it was tough enough to withstand the demolition of the motor room walls. An arrangement was made with the main contractors to crane it down from the motor room and the machine parts and controller from where we had stowed them. We received a call stating that everything was ready for collection, the cranage was paid for and a lorry was despatched to site which returned duly laden. Only later was it discovered that the worm shaft of the gearbox was bent, the brake drum and shaft gland were damaged, one of the sheave bearing pedestals was cracked through and parts of the brake caliper missing or damaged. We assume it was dropped a fair distance, which no-one thought to mention to us!

What happens next?

We now have something that could optimistically be called a project. It’s not top priority, so you won't see it in the workshop any time soon. Perhaps it will be eclipsed by a machine in better condition and just kept for spares. The controller is fun, and although rusty and a bit squashed in places it is eminently restorable. The motor and floor selector are in pretty good shape, tatty looking after having been left lying around outside after initially being more-or-less written off, but fully workable. That leaves the gearbox, pedestal and brake. The brake parts can be replaced. The pedestal can be stitched. That leaves the gearbox. Bill was taking a break from some lathe work and eyeing up the bent shaft. ‘It's not impossible’ he said, with great emphasis on the word ‘impossible.’ We shall see!


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