WO2023135513A1

WO2023135513A1 - Permanent magnet brake

Info

Publication number: WO2023135513A1
Application number: PCT/IB2023/050199
Authority: WO
Inventors: Azadeh NIKOOGOFTARAZIZ
Original assignee: Nikoogoftaraziz Azadeh
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2023-07-20

Abstract

The magnet's attraction and repulsion capabilities were exploited in the novel permanent magnet brake system, and the magnetic field caused by the eddy current does not play any role, thus electric current and coils are not required. Similar to the electric machines, the stator and the rotor layers are employed in this method, which causes the brake in the rotor section to be done without creating friction. Coil (winding wire) was not used in the existing permanent magnet brake, which enhances the factor of safety. Besides, no friction is created between the rotor and the stator; thus, the system does not require a heat sink. Moreover, the power of the brake can be promoted by adding more layers to the collection.

Description

Permanent Magnet Brake

B60K

Electromagnetic permanent magnet brake

United States Patent 8205727

An electromagnetic brake (20), in particular for an electric drive is provided, having a brake body (3), which is provided with a sleeve-shaped permanent magnet (4), an electromagnet (5) with an exciting coil (6), an external ring in the form of an external pole and an internal ring (8) in the form of an internal pole, wherein an armature disc (12) rotatably connected to a shaft is attractable against the brake body (3) or the external or internal ring surfaces by the permanent magnet (4) force acting against a return spring force. When the exciting coil is powered, the permanent magnet (4) magnetic field is compensated in such a way that the armature disc (12) is lifted up from the brake body (3) by the spring force, thereby allowing the brake to be released. A radial cross-sectional dimension or cross-sectional thickness d of the permanent magnet (4) is smaller than the axial dimension thereof and a spatial arrangement, viewed in the axial direction, is provided between the armature disc (12) and the exciting coil (6) in the area radially external with respect to the exciting coil (6) or the housing thereof.

Permanent magnet elevator disk brake

United States Patent 8151950

A brake assembly (18) includes a permanent magnet (36) that generates a first magnetic field (52) in a direction that causes the application of a clamping force on a brake disk (22). An electromagnet (38) is energized with a current of proper polarity to generate a second magnetic field (54) opposite the first magnetic field (52). The rate and magnitude at which current is applied produce a controlled repulsive force between the two magnetic fields (52, 54) to disengage the brake disk (22). As the distance between the permanent magnet (36) and the electromagnet (38) increases, the difference in field strength decreases until an equilibrium position is obtained. The brake is applied and released in a controlled manner by varying the strength of the second magnetic field (54) relative to the first magnetic field generated by the permanent magnet (36).

Permanent magnet vehicle braking apparatus

United States Patent 6025664

A vehicle braking system including a brake drum connected to a rotational shaft; an annular member formed of a ferromagnetic material; a guide frame for supporting the annular member in a position within said spaced from an inner surface of the brake drum; and a cylindrical body defining an uninterrupted wall between the inner surface of the brake drum and the annular member; at least portions of the cylindrical body disposed directly between the inner surface of the brake drum and outer surfaces of the permanent magnets being formed from a magnetically permeable material. Also included are a plurality of annularly arranged permanent magnets circumferentially spaced apart in positions of uniform pitch, the polarities of the permanent magnets facing the inner surface of said brake drum alternating circumferentially; and an actuator for producing axial movement of the annularly arranged permanent magnets into active positions within the brake drum and between the inner surface of the brake drum and the annular member, and inactive positions out of the brake drum. The provision of the cylindrical body with magnetically permeable portions reduces the non-magnetic gap between the brake drum and magnets to thereby increase braking torque.

Switchable permanent magnet brake

United States Patent 4482034

A switchable permanent magnet eddy current or track brake which has a high density of permanent magnet material, a low internal flux leakage, and a higher than heretofore output flux density. The pole shoes of the movable magnets are convex cylindrical segment-shaped and mate with concave cylindrical segment-shaped recesses in the lateral flux return pieces for the fixed magnets

A brake is a mechanical device designed to restrain motion by absorbing energy from a moving system usually by the means of friction. It is used for slowing or stopping a moving automobile, bicycle, motorcycle, etc. The essential function of an electromagnetic brake is to slow down the engine by using electromagnetic force for generating mechanical frictional resistance. These brakes operate via an electrical actuation, but mechanically transfer torque. The magnet's attraction and repulsion capabilities were exploited in the novel-designed system, and the magnetic field caused by the eddy current does not play any role, therefore electric current and coils are not required. Similar to electric machines, stator and rotor layers are employed in this method, which will be elaborately discussed in the following, and the brake is done in the rotor section without causing friction. The operation of the braking system is in this manner: The (N) pole magnets of the two stator layers are placed in front of the (S) pole magnets of the rotor at the same time and conversely the (S) pole of the stators is placed in front of the (N) pole of the rotor. In this case, the magnetic attraction force between two opposite poles causes the braking of the system. The release and rotation of the rotor are in a way that the (S) pole of the first layer stator is aligned with the (N) pole of the second layer stator with the mechanical 90-degree rotation of the two stator layers relative to each other. Deploying these two opposite pole layers in front of the rotor poles results in the neutralization of each other's force and the rotor starts rotating freely.

From 1769 onwards, when the first steam car was devised by the engineer Nicolas-Joseph Cugnot, it also found a desperate need for brakes even though it had a low speed; therefore, he was thinking of a way to reduce the speed of the vehicle and stop it. In the beginning, the brake was operated by hand, whose end was connected to the wheels and stopped the car because of friction. However, with the advancement of mankind, a system was invented in which a small plate named a pad (lining), wire, and a drum-shaped object that was embedded inside the wheels were built. But oil was gradually utilized rather than braking wire, which is known as EBD (Electronic Brake Force Distribution). The most advanced braking system that is currently applied is the Anti-Lock Braking System (ABS), which uses the same components but takes advantage of a disc plate (actuating plate) instead of a brake drum. At present, ABS-ASR-EPS-EBD systems are employed in all cars, which enjoy brake lining, brake drum, and disc plates, all of which have some troubles. The brake linings are worn out and the brakes will be extremely weakened in the event that they are not replaced. The disk plate is damaged over time due to friction with the pads and influences the brake pedal. The pump or oil hoses are leaking and it causes the vehicle not to have brakes in practice. All these items are accompanied by expenses for the car owner, who is forced to pay them. These systems naturally pollute the environment. In some vehicles, the brakes make noise when braking, which causes noise pollution. The primary goal of this invention is to upgrade the safety factor and enhance the braking power.

Solution of problem

A brake is a mechanical device designed to restrain motion by absorbing energy from a moving system usually by the means of friction. It is used for slowing or stopping a moving automobile, bicycle, motorcycle, etc. The essential function of an electromagnetic brake is to slow down the engine by using electromagnetic force for generating mechanical frictional resistance. These brakes operate via an electrical actuation, but mechanically transfer torque.

Dissimilar to mechanical brakes that are based on friction and kinetic energy, eddy current brakes rely on electromagnetism to prevent objects from moving. Eddy currents are generated by passing a conductor through a magnetic field, which creates opposing forces that rotate inside the conductor.

Eddy currents (also called Foucault's currents) are loops of electrical current induced within conductors by a changing magnetic field in the conductor according to Faraday's law of induction or by the relative motion of a conductor in a magnetic field. Eddy currents flow in closed loops within conductors, in planes perpendicular to the magnetic field. They can be induced within nearby stationary conductors by a time-varying magnetic field created by an Ac electromagnet or transformer, for example, or by relative motion between a magnet and a nearby conductor.

The magnet's attraction and repulsion capabilities were exploited in the novel-designed system, and the magnetic field caused by the eddy current does not play any role, thus electric current and coils are not required. Similar to electric machines, stator and rotor layers are employed in this method, which will be elaborately discussed in the following, and the brake happens in the rotor section without causing friction.

This system includes the following components: 1- First layer stator along with the (N and S) pole magnets deployed in it, 2- Second layer stator with the same layout as the first layer in terms of magnet poles, 3- Rotor and rotating part with its internal magnets, and 4- Axis of the machine

Operation of the braking system: The (N) pole magnets of the two stator layers are placed in front of the (S) pole magnets of the rotor at the same time and conversely the (S) pole of the stators is placed in front of the (N) pole of the rotor. In this mode, the magnetic attraction force between two opposite poles causes the braking of the system.

The release and rotation of the rotor are in a way that the (S) pole of the first layer stator is aligned with the (N) pole of the second layer stator with the mechanical 90-degree rotation of the two stator layers relative to each other. Deploying these two opposite pole layers in front of the rotor poles causes the neutralization of each other's force and the rotor starts rotating freely. To put it simply, the brake is removed from the system.

Advantage effects of invention

Coil (winding wire) is not exploited in the existing permanent magnet brake, which enhances the safety factor.

No friction is created between the rotor and the stator, hence, the system does not require a heat sink.

By generating bugs in a part of the machine, the system can continue working.

By adding more layers to the collection, the power of the brake can be upgraded.

: Magnetic braking system

: Components of magnetic brake

: Removal of the holder of the first layer of the magnetic brake stator

: Removal of the holder of the first and second layer of the magnetic brake stator

: Removal of the holder of the first and second layers of the stator and magnetic brake rotor

: 90-degree rotation of the stator of the first layer of the magnetic brake

: Magnetic braking system

: 1. The stator of the first layer (in light gray color) along with N) and (S) pole magnets established in it 2. The stator of the second layer with the same arrangement as the first layer in terms of magnet poles. 3. The rotor and the rotating part shown with their internal magnets. 4. The axis of the device 5. rotor magnet 6. stator magnet

: Removal of the holder of the first layer of the magnetic brake stator

: 90-degree rotation of the stator of the first layer of the magnetic brake

Examples

The release and rotation of the rotor are in a way that the (S) pole of the first layer stator is aligned with the (N) pole of the second layer stator with the mechanical 90-degree rotation of the two stator layers relative to each other. Deploying these two opposite pole layers in front of the rotor poles leads to the neutralization of each other's force and the rotor starts rotating freely. To put it simply, the brake is removed from the system.

In automobiles, a mechanical joint transfers torque to an electromagnetic brake (also called electro-mechanical brake or EM brake) component. Trams and trains utilize electromagnetic brakes, in which the brake is pressed to the rail by magnetic force. They are differentiated from mechanical brakes, where the base of the mechanical brake is pressed on the rim. Electric motors in industrial and robotic applications also employ electromotor magnetic brakes. The design of recent innovations has led to the utilization of electromagnetic brakes in airplanes.

Claims

The magnet's attraction and repulsion capabilities were exploited in the novel permanent magnet brake system, and the magnetic field caused by the eddy current does not play any role, thus electric current and coils are not required. Similar to the electric machines, the stator and the rotor layers are employed in this method, which causes the brake in the rotor section to be done without creating friction.
According to claim 1, this system is composed of the following components: 1- First layer stator along with the (N and S) pole magnets deployed in it, 2- Second layer stator with the same layout as the first layer in terms of magnet poles, 3- Rotor and rotating part with its internal magnets, and 4- Axis of the machine
According to claim 2, the operation of the braking system is in this manner: The (N) pole magnets of the two stator layers are placed in front of the (S) pole magnets of the rotor at the same time and conversely the (S) pole of the stators is placed in front of the (N) pole of the rotor. In this case, the magnetic attraction force between two opposite poles causes the braking of the system.
According to claim 3, the release and rotation of the rotor are in a way that the (S) pole of the first layer stator is aligned with the (N) pole of the second layer stator with the mechanical 90-degree rotation of the two stator layers relative to each other. Deploying these two opposite pole layers in front of the rotor poles leads to the neutralization of each other's force and the rotor starts rotating freely. To put it simply, the brake is removed from the system.
Coil (winding wire) was not used in the existing permanent magnet brake, which enhances the factor of safety. Besides, no friction is created between the rotor and the stator; thus, the system does not require a heat sink. Moreover, the power of the brake can be promoted by adding more layers to the collection.