An elevator brake arrangement includes at least a brake unit including a body, a brake plate assembly, a spring assembly, an electromagnet arrangement and a counter element, and also a rotating brake disc. The brake plate assembly includes at least two brake plates and a state detector that is arranged to monitor the operation states of the brake plates.

An electromagnetic brake is provided in which short duration current pulses move the brake between engaged and disengaged states. A first current pulse having a first polarity is delivered to a conductor within a field shell when the brake is engaged and establishes an electromagnetic circuit including the field shell and an armature plate that urges the armature plate away from a rotating friction plate and towards the field shell to disengage the brake. A magnetic circuit is maintained after termination of the first current pulse due to a remanence in at least one of the armature plate and the field shell. A second current pulse having a second polarity opposite the first polarity delivered to the conductor when the brake is disengaged weakens the magnetic circuit thereby allowing a spring to move the armature plate away from the field shell and towards the friction plate to engage the brake.

An electromagnetic brake is provided in which short duration current pulses move the brake between engaged and disengaged states. A first current pulse having a first polarity is delivered to a conductor within a field shell when the brake is engaged and establishes an electromagnetic circuit including the field shell and an armature plate that urges the armature plate away from a rotating friction plate and towards the field shell to disengage the brake. A magnetic circuit is maintained after termination of the first current pulse due to a remanence in at least one of the armature plate and the field shell. A second current pulse having a second polarity opposite the first polarity delivered to the conductor when the brake is disengaged weakens the magnetic circuit thereby allowing a spring to move the armature plate away from the field shell and towards the friction plate to engage the brake.

A normally closed disc clamp system includes a housing with a rotating disc, a brake ring and a pressure-enhancing ring arranged therein. When only a first chamber is supplied with fluid, the fluid pushes the brake ring to release the rotating disc. When only a second chamber is fed with fluid, the fluid pushes the brake ring to keep the rotating disc in the braking state, and pushes the pressure-enhancing ring to compress an elastic unit. The energy generated by the compression of the elastic unit acts on the brake ring through the fluid, so that the brake ring achieves a double pressurization effect. If the action of the fluid fails, the brake ring can still provide a braking effect to the rotating disc through the elastic unit to improve operational safety. Further, the present invention further provides a rotating table using the normally closed disc clamp system.

A normally closed disc clamp system includes a housing with a rotating disc, a brake ring and a pressure-enhancing ring arranged therein. When only a first chamber is supplied with fluid, the fluid pushes the brake ring to release the rotating disc. When only a second chamber is fed with fluid, the fluid pushes the brake ring to keep the rotating disc in the braking state, and pushes the pressure-enhancing ring to compress an elastic unit. The energy generated by the compression of the elastic unit acts on the brake ring through the fluid, so that the brake ring achieves a double pressurization effect. If the action of the fluid fails, the brake ring can still provide a braking effect to the rotating disc through the elastic unit to improve operational safety. Further, the present invention further provides a rotating table using the normally closed disc clamp system.

An electromagnetic brake is provided in which short duration current pulses move the brake between engaged and disengaged states. A first current pulse having a first polarity is delivered to a conductor within a field shell when the brake is engaged and establishes an electromagnetic circuit including the field shell and an armature plate that urges the armature plate away from a rotating friction plate and towards the field shell to disengage the brake. A magnetic circuit is maintained after termination of the first current pulse due to a remanence in at least one of the armature plate and the field shell. A second current pulse having a second polarity opposite the first polarity delivered to the conductor when the brake is disengaged weakens the magnetic circuit thereby allowing a spring to move the armature plate away from the field shell and towards the friction plate to engage the brake.

An electromagnetic brake is provided in which short duration current pulses move the brake between engaged and disengaged states. A first current pulse having a first polarity is delivered to a conductor within a field shell when the brake is engaged and establishes an electromagnetic circuit including the field shell and an armature plate that urges the armature plate away from a rotating friction plate and towards the field shell to disengage the brake. A magnetic circuit is maintained after termination of the first current pulse due to a remanence in at least one of the armature plate and the field shell. A second current pulse having a second polarity opposite the first polarity delivered to the conductor when the brake is disengaged weakens the magnetic circuit thereby allowing a spring to move the armature plate away from the field shell and towards the friction plate to engage the brake.

A brake disk defines an annular shape having a radially inner side and a radially outer side. The brake disk includes: a radially outer braking surface, the braking surface having a maximum operating temperature; a fusible material section radially inward from and connected to the braking surface. The fusible material has a maximum operating temperature, the fusible material section suitable for transmitting torque between the braking surface and a shaft. The maximum operating temperature of the braking surface is higher than the maximum operating temperature of the fusible material section. When the temperature of the fusible material section raises above the maximum operating temperature of the fusible material section, the fusible material section is configured to no longer transmit torque between the braking surface and the shaft.

In a non-excitation operative brake, a friction plate faces the inner disk part of an attraction plate made from a magnetic material, and an electromagnet faces the outer disk part of the attraction plate. A part for generating a brake force acting on a hollow shaft is located on an inner circumferential side in a radial direction of the attraction plate, while a part for magnetically attracting the attraction plate so as to release the brake force is located on an outer circumferential side in the radial direction of the attraction plate. A flat non-excitation operative brake having a reduced length in the direction of an axis line can be realized.

In a non-excitation operative brake, a friction plate faces the inner disk part of an attraction plate made from a magnetic material, and an electromagnet faces the outer disk part of the attraction plate. A part for generating a brake force acting on a hollow shaft is located on an inner circumferential side in a radial direction of the attraction plate, while a part for magnetically attracting the attraction plate so as to release the brake force is located on an outer circumferential side in the radial direction of the attraction plate. A flat non-excitation operative brake having a reduced length in the direction of an axis line can be realized.