Abstract: A sliding door drive system may include a drive axle and at least one idler axle spaced a part and parallel to each other. The sliding door drive system may further include a first pair of gears having a first radius, each of which is coupled to a different one of the drive axle and the at least one idler axle. The sliding door drive system may further include a second pair of gears having a second radius larger than the first radius. The sliding door drive system may further include a first drive belt coupled between the first pair of gears, and a second drive belt coupled between the second pair of gears. The sliding door drive system may further include a first door bracket coupled to the first drive belt and a second door bracket coupled to the second drive belt.

Abstract: A sliding door drive system may include a drive axle and at least one idler axle spaced a part and parallel to each other. The sliding door drive system may further include a first pair of gears having a first radius, each of which is coupled to a different one of the drive axle and the at least one idler axle. The sliding door drive system may further include a second pair of gears having a second radius larger than the first radius. The sliding door drive system may further include a first drive belt coupled between the first pair of gears, and a second drive belt coupled between the second pair of gears. The sliding door drive system may further include a first door bracket coupled to the first drive belt and a second door bracket coupled to the second drive belt.

Abstract: Systems and methods for monitoring the bottom of the doors to an elevator to increase safety in and around the elevator cab and prevent dangerous conditions when a hallway or cab door to the elevator is damaged, loose, misaligned, or malfunctioning.

Abstract: An elevator level warning system is provided, along with methods of use thereof. An elevator level warning system may include a controller, a laser, a sensor, and a reflector. The reflector may be a structured reflector. The elevator level warning system may also include a sensor board. The elevator level warning system may also include an indicator. The elevator level warning system may be used with an elevator system. The elevator level warning system may be used to detect that-and/or warn users that-a front cab-floor edge and a landing plane are misaligned and have a drop between them of greater than a threshold distance.

Abstract: A power supply circuit for powering components of a facility are disclosed. The power supply circuit may include a power transformer, a power input terminal, a power output terminal, a bridge, a relay, and a control circuit. The relay is connected between the power input terminal and the power output terminal. A primary side of the power transformer is coupled between the relay and the power output terminal. The bridge is coupled to the secondary side of the power transformer. In a normal power mode, the control circuit closes the relay and operates the bridge as a rectifier. In an emergency power mode, the control circuit opens the relay and operates the bridge as a pulse width modulator. In this manner, the bridge and the power transformer can be used both to charge a battery during normal operation and generate emergency AC power from the battery.

Abstract: An elevator pit safety system is provided, along with methods of use thereof. An elevator pit safety system may include a control system, an emergency stop switch, and a power switch. The emergency stop switch may be configured to stop an elevator cab. The power switch may be configured to operate a lighting system. The control system may prevent either from being used without the other. The elevator pit safety system may be configured to allow overriding the safety features.

Abstract: An elevator cab includes primary and auxiliary light sources. A light sensor responsive to light from the primary light source causes activation of the auxiliary light source when the primary light source fails. The light sources are inside the cab for passenger use and/or outside the cab for maintenance worker use. A battery for auxiliary light is selectively charged by first and second current levels in response to the battery voltage being above or below first or second different thresholds.