A method for determining a speed of an electric motor of an elevator comprising a plurality of phases for supplying electric current to the electric motor. The method comprises forming an effective short-circuit between at least two of the plurality of phases of the electric motor, determining a short-circuit current, the short-circuit current being the current flowing in the effective short-circuit, and determining the speed of the electric motor based on at least one characteristic of the short-circuit current.

A method for determining a speed of an electric motor of an elevator comprising a plurality of phases for supplying electric current to the electric motor. The method comprises forming an effective short-circuit between at least two of the plurality of phases of the electric motor, determining a short-circuit current, the short-circuit current being the current flowing in the effective short-circuit, and determining the speed of the electric motor based on at least one characteristic of the short-circuit current.

An adjustable brake controller of an elevator brake comprises a DC bus; first terminals for connecting the brake controller to a first magnetizing coil; second terminals for connecting the brake controller to a second magnetizing coil; a first controllable power switch coupled between the first terminals and the DC bus, the first controllable power switch being configured to supply electric power from the DC bus to the first magnetic coil responsive to a first control signal; a second controllable power switch coupled between the second terminals and the DC bus, the second controllable power switch being configured to supply electric power from the DC bus to the second magnetizing coil responsive to a second control signal; and a controller configured to generate the first and the second control signals for controlling the first and second power switches, respectively. The controller has: a brake open mode, wherein the first and second control signals have a same specified pattern, and a brake holding mode wherein the first and second control signals have a different specified pattern.

An adjustable brake controller of an elevator brake comprises a DC bus; first terminals for connecting the brake controller to a first magnetizing coil; second terminals for connecting the brake controller to a second magnetizing coil; a first controllable power switch coupled between the first terminals and the DC bus, the first controllable power switch being configured to supply electric power from the DC bus to the first magnetic coil responsive to a first control signal; a second controllable power switch coupled between the second terminals and the DC bus, the second controllable power switch being configured to supply electric power from the DC bus to the second magnetizing coil responsive to a second control signal; and a controller configured to generate the first and the second control signals for controlling the first and second power switches, respectively. The controller has: a brake open mode, wherein the first and second control signals have a same specified pattern, and a brake holding mode wherein the first and second control signals have a different specified pattern.

An electronic actuator for an elevator safety brake system, the actuator having: an electromagnet assembly; and a first magnet assembly configured for being retracted from engagement with a rail depending on an energized state of the electromagnet assembly, the first magnet assembly including: blocks spaced apart from each other, respectively defining block bodies, and elongated block legs respectively extending aft from the block bodies; and a first magnet is disposed between the block bodies; wherein the electromagnet assembly includes: a core that defines: a core body extending between core ends that are spaced apart from each other; and core stub legs respectively extending forward from the core ends that are positioned adjacent to the elongated block legs when the first magnet assembly is retracted; and a coil winding wound about bobbins that are placed over the core body, the elongated block legs are longer than the core stub legs.

An electronic actuator for an elevator safety brake system, the actuator having: an electromagnet assembly; and a first magnet assembly configured for being retracted from engagement with a rail depending on an energized state of the electromagnet assembly, the first magnet assembly including: blocks spaced apart from each other, respectively defining block bodies, and elongated block legs respectively extending aft from the block bodies; and a first magnet is disposed between the block bodies; wherein the electromagnet assembly includes: a core that defines: a core body extending between core ends that are spaced apart from each other; and core stub legs respectively extending forward from the core ends that are positioned adjacent to the elongated block legs when the first magnet assembly is retracted; and a coil winding wound about bobbins that are placed over the core body, the elongated block legs are longer than the core stub legs.

A frictional damper for an elevator system includes one or more friction pads configured to move between a first position, and a second position defined by engagement of the one or more friction pads to the guide rail. An actuation unit urges the one or more friction pads into and out of engagement with the guide rail. The actuation unit includes a hydraulic actuator operably connected to the one or more friction pads to urge movement of the one or more friction pads into and out of engagement with the guide rail via hydraulic fluid pressure. The hydraulic actuator includes a hydraulic cylinder containing a volume of hydraulic fluid and a hydraulic piston located in the hydraulic cylinder and operably connected to the one or more friction pads. An electromagnetic actuator selectably urges hydraulic fluid to apply a force to the hydraulic piston, urging the movement of the friction pads.

The invention concerns a rescue apparatus, an elevator as well as a retrofit kit. The rescue apparatus comprises a brake control unit having input terminals for connecting to a power supply, output terminals for connecting to a magnetizing coil of an electromagnetic brake, at least one controllable brake opening switch associated with at least one of the input terminals and adapted, in an open state, to prevent supply of current from the power supply to the magnetizing coil and, in a closed state, to allow supply of current from the power supply to the magnetizing coil. The rescue apparatus further comprises a control cable comprising one or more control signal wires and a remote control panel coupled via the control cable to the brake control unit.

The invention concerns a rescue apparatus, an elevator as well as a retrofit kit. The rescue apparatus comprises a brake control unit having input terminals for connecting to a power supply, output terminals for connecting to a magnetizing coil of an electromagnetic brake, at least one controllable brake opening switch associated with at least one of the input terminals and adapted, in an open state, to prevent supply of current from the power supply to the magnetizing coil and, in a closed state, to allow supply of current from the power supply to the magnetizing coil. The rescue apparatus further comprises a control cable comprising one or more control signal wires and a remote control panel coupled via the control cable to the brake control unit.

An elevator safety monitoring system, an elevator system, an elevator drive unit, and a method for operating an elevator are presented. The elevator safety monitoring system includes an elevator car absolute position and speed feedback device, a safety monitor connected to the absolute position and speed feedback device, and a safety zone extending inside an elevator shaft. The safety zone is associated with an allowable maximum speed of an elevator car, wherein the allowable maximum speed is lower than a rated speed of an elevator car outside the safety zone, wherein the safety monitor is configured to determine a slowdown failure of the elevator car approaching the safety zone, and, upon the determination of the slowdown failure, command an actuator to decelerate the elevator car to the allowable maximum speed.