An overhead lift includes a lift strap, a motor, an electromagnetic brake, and a release assembly. The motor includes a rotatable shaft coupled to the lift strap. The electromagnetic brake is coupled to the rotatable shaft and has an engaged state and a disengaged state. The release assembly is engaged with the electromagnetic brake. The release assembly incudes a release lever engaged with the electromagnetic brake and a release strap. The release lever is moveable between a first position and a second position, wherein the release lever switches the electromagnetic brake to the disengaged state when in the second position. The release strap is coupled to the release lever. Tensioning of the release strap moves the release lever from the first position to the second position thereby switching the electromagnetic brake to the disengaged state.

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 chain tensioning arrangement for a column pipe which is configured to house a submersible pump. The chain tensioning arrangement includes a radially extending cross beam, a spring arrangement connected to the cross beam, at least one spring member, and an arm that is movably connected to the cross beam. The arm includes an engagement member configured to optionally engage a chain connected to the pump. The arm is displaceable in the axial direction between a lower position and an upper position. The spring member is arranged to displace the arm in the direction from the lower position towards the upper position. Also described is a pump station including a column pipe, a submersible pump arranged in the column pipe and an axially extending chain connected to the pump and configured to move the pump in the column pipe.

Embodiments herein relate to a permanent magnet (PM) motor driven hoist with a motor based electromagnetic brake. The hoist includes a direct current (DC) power source, a PM motor having stator coils and a PM rotor operably coupled to a cable drum with a cable wrapped thereon. The hoist also includes a controller operably connected to the direct current power source and the PM motor, wherein the controller is configured to control the PM motor employing a method to brake the PM motor. The method includes generating control signals in the controller based on a position of the PM motor, applying a braking command signal to the PM motor to magnetically lock the PM rotor of the PM motor for a selected duration, removing the braking command signals for a second selected duration, and repeating the generating, applying, and removing until the PM motor has stopped.

A propulsion unit includes a platform, a propulsion assembly, and a tether. The propulsion assembly facilitates selective launching of a tire deflation device from the platform. The tether is coupled to the platform and is configured for attachment to a deflation device.

An electric winch device includes a required braking force estimation section which estimates a required braking force required to stop a free-falling object at a position at an allowable stopping height; a braking force determination section which determines, out of an operational braking force, each of a first braking force to be borne by a braking device and a second braking force to be borne by a braking force which is generated in an electric motor due to consumption of regenerative power; and a control section which causes the braking device to apply the first braking force to a winch drum. The braking force determination section determines the first braking force to be a braking force equal to or greater than the required braking force when, at a time of stopping of the free-falling object, the operational braking force is equal to or greater than the required braking force.

A lift system comprises a drum that rotates about an axis, an elongate member that winds around the drum when the drum rotates in a first direction and that unwinds from the drum when the drum rotates in a second direction, a drive mechanism operable to rotate the drum, and a braking mechanism adapted to inhibit rotation of the drum. The braking mechanism includes a brake disk rotatable with the drum, a movable brake pad, and a ramp that guides movement of the movable brake pad. A method of operating the lift system comprises rotating the drum in a first direction to wind the elongate member onto the drum, rotating the drum in a second direction to unwind the elongate member from the drum, and moving the brake shoe along the ramp to thereby cause the movable brake pad to be compressed against the brake disk.

A manually operated counterweight hoist including a batten operable to support a load, an arbor operable to support one or more counterweights, a hand line operable to move the batten or the arbor, a brake operable to prevent movement of the arbor and the batten by constricting movement of the hand line, a brake actuator operable to activate the brake, a sensor that measures a speed of the arbor, and a controller including an electronic processor. The controller is operatively coupled to the sensor and the brake actuator. The controller is configured to receive a measurement signal from the sensor, determine whether the speed of the arbor exceeds a threshold based on the measurement signal, and activate the brake actuator when the speed of the arbor exceeds the threshold.