Lift

A lift apparatus comprising a lift, means for raising and lowering the lift, a first brake actuable to prevent movement of the lift, movement detecting means comprising a tachometer for detecting movement of the means for raising and lowering when the first brake is actuated, guide means for directing the lift, a second brake, actuable to prevent movement of the lift by acting on the guide means, and means for actuating the second brake when movement of the lift is detected by the movement detecting means, so that the second brake stops slippage of the lift when the first brake is actuated.

In an apparatus for controlling movement of a lift having a drive means, a first brake means to prevent movement of the lift and guide means for directing the lift, the improvement comprising means for detecting movement of the lift when the first brake means is actuated, means for detecting actuation of said drive means, a second brake means to prevent movement of the lift by acting on the guide means, and control means responsive to at least said means for detecting movement of the lift and said means for detecting actuation of said drive means for actuating the second brake means when movement of the lift is detected by the movement detecting means and the first brake means is actuated and the drive means is stopped, whereby the second brake means stops any slippage of the lift that may occur when the first brake means is operated.

In an apparatus for controlling movement of a lift having means for driving the lift, a first brake means to prevent movement of the lift and guide means for directing the lift, the improvement comprising means for detecting movement of the lift including means for detecting movement of the drive means when the first brake means is actuated, a second brake means to prevent movement of the lift by acting on the guide means, and means for actuating the second brake means when movement of the lift is detected by the movement detecting means, said means for actuating comprising control circuit means including means for detecting actuation of a drive motor and means for detecting actuation of the first brake means.

An apparatus for controlling movement of a lift and comprising, means for driving the lift, brake means associated with said means for driving, means for detecting actuation of said driving means, means for detecting movement of said lift, guide means for directing movement of said lift, means for detecting actuation of said brake means, means for inhibiting fall of said lift which act on said guide means, and control means responsive to said means for detecting actuation of said drive means, said means for detecting movement of said lift and said means for detecting actuation of said brake means, for operating said means for inhibiting when said drive means is stopped, and said brake means is actuated, and said lift is moving.

A lift apparatus comprising a lift, means for raising and lowering the lift including sheave means and cable, a first brake means associated with said means for raising and lowering and actuable to prevent movement of the lift, movement detecting means for detecting movement of the lift even though the first brake means is actuated, said movement detecting means comprising means for detecting movement of only the sheave means without relative movement between the sheave means and the cable means, a second brake means actuable to prevent movement of the lift, and means for actuating the second brake means when movement of the lift is detected by the movement detecting means, so that the second brake means stops slippage of the lift when the first brake means is actuated.