Otis Elevator Company

Klaus Bruehl

Dietmar Thaler

Willy Adrian

The tension on the moving handrail drive and/or step chain of a passenger conveyor such as an escalator or moving walkway is automatically released when the conveyor is shut down; and is automatically reapplied when the conveyor is started up again. Undesirable compression and localized flattening of the elastomeric components of the conveyor are thus avoided.

Tension release for passenger conveyor

An hydraulic buffer or brake is provided on an escalator to stop movement of the steps in case power is interrupted, or if a safety device is activated. The braking action occurs in parallel to the inclination of the step chain. The braking action occurs in several stages so that a maximum time delay between initiation of the device and stopping of the steps can be achieved. In the first stage, the braking force is more solely applied, so that the first stage can affect a stopping of an empty escalator when completed. In the second stage the braking force is more quickly applied, so that the first and second stages can affect a stopping of a heavily loaded escalator in concert in the same maximum deceleration as the first stage can, when completed stop the lightly loaded escalator.

Escalator step buffer

The handrail of an escalator of other passenger conveyor is driven by traction rollers which engage the handrail and also directly engage links which are connected to and drive the steps or tread of the conveyor. The handrail is biased into engagement with the traction rollers, and moves at substantially precisely the same speed as the steps or tread due to the direct connection between the step or tread drive and the handrail drive.

Growing community of inventors

Hanover, Germany

Klaus Bruehl