An adjustable brake controller of an elevator brake including 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, with a brake open mode and a brake holding mode.

The invention discloses a power-loss triggering device, including: a frame, an electromagnet and an impact bar; the impact bar vertically and movably penetrates through the frame; an energy storage piece is arranged and the energy storage piece may exert a downward action force on the impact bar; when the electromagnet is energized, the impact bar is positioned through electromagnetic force; when the electromagnet loses power, the impact bar loses a holding power from the electromagnet and conducts a downward impact movement under the action force of the energy storage piece. The power-loss triggering device is implemented through the electromagnet and an intermediate mechanism. In this invention, the electric current, the energy consumption and the cost of the electromagnet are reduced, the service life of the long-time energized electromagnet is prolonged.

The invention discloses a power-loss triggering device, including: a frame, an electromagnet and an impact bar; the impact bar vertically and movably penetrates through the frame; an energy storage piece is arranged and the energy storage piece may exert a downward action force on the impact bar; when the electromagnet is energized, the impact bar is positioned through electromagnetic force; when the electromagnet loses power, the impact bar loses a holding power from the electromagnet and conducts a downward impact movement under the action force of the energy storage piece. The power-loss triggering device is implemented through the electromagnet and an intermediate mechanism. In this invention, the electric current, the energy consumption and the cost of the electromagnet are reduced, the service life of the long-time energized electromagnet is prolonged.

A variable frequency drive motor system includes a variable frequency drive motor and a controller coupled to the motor. The controller includes a rectifier, a direct current (DC) link bus, and an inverter. The controller is configured to determine that a brake has failed. In response to the determination that the brake has failed, the controller is configured to determine that power to the controller from a power supply has been interrupted. In response to the determination that power to the controller has been interrupted and a determination that a DC voltage across the DC link bus is below a first threshold value, the controller is configured to drive the motor at a faster speed.

The purpose of the invention is to detect a failure situation wherein the machinery brake of an elevator does not open sufficiently. In the method for testing failure of a machinery brake of an elevator, the machinery brake is controlled to open. After this, the traction sheave is oscillated with a test torque, the movement of the elevator machine is measured in connection with the oscillation, and if the machine does not move in connection with the oscillation, it is deduced that the machinery brake has not opened and has therefore failed.

The purpose of the invention is to detect a failure situation wherein the machinery brake of an elevator does not open sufficiently. In the method for testing failure of a machinery brake of an elevator, the machinery brake is controlled to open. After this, the traction sheave is oscillated with a test torque, the movement of the elevator machine is measured in connection with the oscillation, and if the machine does not move in connection with the oscillation, it is deduced that the machinery brake has not opened and has therefore failed.

The present invention is implemented by a gantry binary synchronization block-type brake, which comprises: a gantry bracket comprised by a fixedly connected door-shaped frame; braking arms arranged on both sides of the gantry bracket with lower ends of the braking arms hinged to the gantry bracket; braking shoes connected to the braking arms for frictionally braking a braking wheel; a dual brake releaser secured to the gantry bracket for pushing the two braking arms outward synchronously; braking springs provided on the gantry bracket for pushing the braking arms so as to perform normal-mode braking; and a gap adjustment mechanism for adjusting a working gap between the braking shoes and the braking wheel. According to the present invention, the security risks in an elevator tractor or crane can be eliminated, the gap adjustment approach is simple, and reliability and versatility of an operation are considerably enhanced.

The present invention is implemented by a gantry binary synchronization block-type brake, which comprises: a gantry bracket comprised by a fixedly connected door-shaped frame; braking arms arranged on both sides of the gantry bracket with lower ends of the braking arms hinged to the gantry bracket; braking shoes connected to the braking arms for frictionally braking a braking wheel; a dual brake releaser secured to the gantry bracket for pushing the two braking arms outward synchronously; braking springs provided on the gantry bracket for pushing the braking arms so as to perform normal-mode braking; and a gap adjustment mechanism for adjusting a working gap between the braking shoes and the braking wheel. According to the present invention, the security risks in an elevator tractor or crane can be eliminated, the gap adjustment approach is simple, and reliability and versatility of an operation are considerably enhanced.

A brake, which includes a frame part of the brake, an armature part movably supported on the frame part, and attached to the frame part a limit switch, the switching state of which changes when movement is exerted on the limit switch in the operating direction of the limit switch. The brake also includes a measuring pin that is movably supported on the frame part of the brake and that is separate from the armature part, which measuring pin is connected to the limit switch.

A brake, which includes a frame part of the brake, an armature part movably supported on the frame part, and attached to the frame part a limit switch, the switching state of which changes when movement is exerted on the limit switch in the operating direction of the limit switch. The brake also includes a measuring pin that is movably supported on the frame part of the brake and that is separate from the armature part, which measuring pin is connected to the limit switch.