Features

The " Rope GripperTM " uses springs along a stationary cam to obtain a mechanical advantage and apply adequate pressure to the elevator suspension ropes without any damages to the traction machine, sheaves and others.

This cam action causes a changing mechanical advantage and is designed to compensate for lining wear and lengthening springs, providing a constant force on the elevator ropes, even with the spring extended to less than half their original compressed value.

Open Position (Normal Status)

When the " Rope GripperTM " is in its open position, the springs are fully compressed and prevented from extending by an electric solenoid trigger mechanism.

When the electric solenoid is de-energized, the springs will extend forcing the movable shoe against the ropes.

Gripping

When an emergency condition exists (overspeed or the elevator outside of door zone with doors opened), the contact on the elevator controller will disconnect the electric solenoid releasing the trigger mechanism, to grip the suspension rope and stop the elevator. As the springs extend, the oil is forced from a cylinder into a tank allowing a smooth shock absorbing action.

The contact on the " Rope GripperTM " will open so that power to the elevator motor will be disconnected and/or remain disconnected until the " Rope GripperTM " is once again reset.

Resetting

To reset the " Rope GripperTM " after it has been set (gripping ropes), a contact on the elevator controller will close indicating all signals are normal.

The pump motor will be energized along with the electric trigger solenoid. Then, a hydraulic dump valve is closed and oil will be pumped into the cylinder causing the springs to compress and move down the cam. The plunger will retract into the cylinder compressing the springs.

When the " Rope GripperTM " reaches the open ready position, a microswitch will disconnect the pump motor and the electric solenoid will keep the brake in the open position. A contact on the " Rope GripperTM " will indicate that the elevator can run.

[Remark]

In the unlikely event of excessive use, the shoe lining may wear so that the shaft extends to near the end of the cam, however, a microswitch is provided which will prevent resetting of the " Rope GripperTM " and will not allow the elevator to run until the " Rope GripperTM " is re-adjusted.

As the linings wear, the rotating shaft will go higher up the cam although the springs become weaker in this condition, the mechanical advantage becomes greater allowing a constant pressure of the linings on the ropes.

Installation Pictures