JPH1014298A - Electromagnetic braking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic braking device, which freely controls the braking power generated in a wide rage of running speed of a vehicle, from a low speed to high speed, gas a simple structure and is applicable for downsizing the device. SOLUTION: At the periphery of a magnet rotor 4 which integrally rotates with a rotation axis 3, magnetic pole sensors 11 and 12, which detects a magnetic pole on the outer circumference of the magnet rotor 4, and a plurality of stators 6A-6D are arranged. Each stator edge 7 is permitted to be a magnetic pole by energizing exciting coils 9 provided on respective stators 6A-6D, so as to operate a magnetic force in a direction opposite to the rotation of the rotating axis, between the edges of respective stators 6A-6D and the magnet rotor 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic brake device suitable for use as an auxiliary brake device for a vehicle or the like, and more particularly, to a magnet rotor connected to a rotating shaft and disposed around the magnet rotor. The present invention relates to an electromagnetic brake device that generates a braking force on the rotating shaft by an electromagnetic force between the electromagnetic shaft and a stator.

[0002]

2. Description of the Related Art It is known that large vehicles such as trucks and buses are equipped with an auxiliary brake device in addition to a friction brake device as a main brake. The auxiliary brake device generates braking torque, for example, when decelerating from a high speed on a downhill, prevents a fade due to a rise in temperature of the friction brake device, and improves vehicle safety and durability of the friction material. As the auxiliary brake device, a hydraulic retarder (actually disclosed in Japanese Unexamined Utility Model Publication No.
Japanese Patent Application Laid-Open No. 4-161)
No. 054) is known.

[0003]

However, in each of the above-mentioned fluid type retarders and eddy current type retarders, the braking force depends on the running speed of the vehicle, and when the running speed of the vehicle is low, the braking force is small. There was a problem that only power could be exerted and used only as an auxiliary braking device. There is also a problem that the driver cannot freely control the magnitude of the braking force generated like the main brake over a wide range. In the case of a fluid type retarder, a pump, a reservoir, a radiator, and the like are required, so that there is a problem that the apparatus is complicated and large.

Accordingly, an object of the present invention is to solve the above problems, and when used as a vehicle brake device, the magnitude of the generated braking force can be freely controlled over a wide range regardless of the running speed of the vehicle. It is another object of the present invention to provide an electromagnetic brake device which has a simple structure and is suitable for downsizing the device.

[0005]

According to the present invention, there is provided an electromagnetic brake apparatus comprising: a magnet rotor which rotates integrally with a rotating shaft; and a circumferentially spaced space around the magnet rotor. And a stator provided at a plurality of locations spaced apart from the outer peripheral surface of the magnet rotor by a fixed distance, and a stator end provided for each stator and facing the magnet rotor by energization, having an N pole or S pole.
A magnetic pole sensor that is provided at an intermediate position between adjacent stators and detects a magnetic pole on a magnet rotor passing the position; a detection signal of the magnetic pole sensor and rotation of the magnet rotor; A control circuit for controlling the energization of the excitation coil of each stator based on the direction, and the control circuit includes:
The power supply apparatus further includes an energization polarity setting unit that controls a magnetic pole at the end of the stator based on an output signal of a magnetic pole sensor that detects a magnetic pole of the magnet rotor.

Alternatively, the control circuit may include a magnetic field strength setting means for controlling a magnetic field strength at the end of the stator.

When the magnetic pole sensor detects the magnetic poles on the outer periphery of the magnet rotor, the energizing polarity setting means determines the energizing polarities of the exciting coils on each stator based on the rotation direction of the magnet rotor. A magnetic repulsive force and an attractive force are generated therebetween, thereby generating a braking force for suppressing rotation. In this way, by applying a magnetic repulsive force and an attractive force against the rotation direction of the magnet rotor from the ends of all the stators arranged around the magnet rotor, the rotating shaft to which the magnet rotor is connected is braked. Is done.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an electromagnetic brake device according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of one embodiment of an electromagnetic brake device according to the present invention. This electromagnetic force braking device 1
Is mounted on a vehicle and used as a brake device, and has a substantially disk shape (or a cylindrical shape), and has a magnetic north pole (denoted as “N” in the drawing) and an south pole (“S” in the drawing). ')
Are arranged at two opposing positions on the outer periphery with the rotation center interposed therebetween, and a magnet rotor 4 that rotates integrally with the rotating shaft 3, and a magnet rotor 4 is provided around the magnet rotor 4 at equal intervals in the circumferential direction and at the same time. Stator 6 mounted at a plurality of locations (four locations in the figure) separated by a fixed distance from the outer peripheral surface of
A, 6B, 6C, and 6D; an excitation coil 9 provided for each of the stators 6A to 6D to turn the stator end 7 on the magnet rotor 4 side into an N-pole or an S-pole by energization; A pair of magnetic pole sensors 11 and 12 which are provided at intermediate positions of the magnet rotor 4 and detect magnetic poles on the magnet rotor 4 passing therethrough; rotation detecting means 14 for detecting the rotation direction of the magnet rotor 4;
The control circuit 16 controls the energization of the exciting coils 9 of the stators 6A to 6D based on detection signals of the rotation detection means 1 and 12 and the rotation detection means 14.

The electromagnetic force braking device 1 applies a braking force to the rotating shaft 3 by an electromagnetic force acting between the magnet rotor 4 and each stator end 7 by turning each stator end 7 into a magnetic pole. An axle or a transmission output shaft corresponds to the rotating shaft 3.

The magnetic pole sensors 11 and 12 use Hall elements and are provided between different stators.
In this embodiment, the rotation detecting means 14 detects the rotation direction of the magnet rotor 4 by turning on / off a back gear (reverse gear) switch in the transmission of the vehicle. When the reverse gear switch is off (that is, when the vehicle is moving forward), the rotation direction of the magnet rotor 4 is detected assuming that the magnet rotor 4 rotates forward (clockwise in the figure).

The control circuit 16 controls the brake pedal 1 of the vehicle.
The operation is started when the driver depresses the brake pedal 18 by monitoring the pedal sensor 20 that detects the operation amount (stepping amount or stepping force) of the driver 8. The control circuit 16 includes an energization polarity setting unit 22 and a magnetic field intensity setting unit 23. Here, the energization polarity setting means 22
Magnetic pole sensor 11 that detects the magnetic pole of magnet rotor 4
Alternatively, with respect to the position of the magnetic pole sensor 12, the ends of the stators 6A and 6B on the magnet rotor 4 side, which are located in a half circumference on the front side in the rotation direction of the magnet rotor 4 from the magnetic pole sensors 11 and 12, are the magnetic pole sensor 11, 12 are poled to the same polarity as the detected poles, and the stators 6C, 6D
The current supply polarity to each of the excitation coils 9 is set so that the stator end 7 of the above-mentioned is poled to a polarity opposite to the polarity detected by the magnetic pole sensors 11 and 12. More specifically, the switching is performed by switching between the positive and negative DC power supplies.

The magnetic field strength setting means 23 is provided for each excitation coil 9.
The magnitude of the exciting current or the duty ratio of the exciting pulse is controlled according to the operation amount of the brake pedal 18 so that the magnetic field strength of each stator end 7 is controlled by the brake pedal 18.
Is controlled to a size corresponding to the operation amount of.

In the above-described electromagnetic braking device 1, for example, when the brake pedal 18 is depressed during forward running (when the magnet rotor 4 is rotating clockwise in FIG. 2), the control circuit 16 is activated. The magnetic pole sensor 11 operates as shown in FIG.
When the pole is detected, the energizing polarity setting means 22 determines the energizing polarity of the exciting coil 9 on each of the stators 6A to 6D based on the signal from the rotation detecting means 14, and the ends 7 of the stators 6A and 6B are set to N. At the same time as being poled, the stator 6C,
The end 7 of 6D is poled to an S pole. Therefore, the stator end 7 in the first half in the rotation direction of the magnet rotor 4 has
The same north pole as the north pole on the magnet rotor 4 is arranged, and the stator end 7 in the latter half of the rotation direction of the magnet rotor 4 has the south pole on the magnet rotor 4 located on the opposite side to the magnetic pole sensor 11. A state in which the same south poles are arranged is formed.

Therefore, between the stator 6A and the N pole of the magnet rotor 4 and between the stator 6C and the magnet rotor 4
Repulsive force is generated between the starter 6B and the S pole of the magnet rotor 4 and between the stator 6D and the N pole of the magnet rotor 4, thereby generating an attractive force. A braking force for suppressing the rotation of the motor is generated. As described above, the magnet rotor 4 is connected by applying the magnetic repulsive force and the attractive force against the rotation direction of the magnet rotor 4 from the end portions 7 of all the stators 6A to 6D arranged around the magnet rotor 4. The rotating shaft 3 is braked.

Then, the magnet rotor 4 further rotates against the magnetic force from the end 7 of each of the stators 6A to 6D, and as shown in FIG. When the magnetic pole sensor 12 is reached, the magnetic pole sensor 12 detects its north pole, and as a result, the stators 6B, 6
At the same time that the end 7 of the C is magnetized to the N pole,
The ends 7 of A, 6D are magnetically poled to S poles, and each stator 6
The state where the braking force is applied to the magnet rotor 4 by the magnetic repulsion force and the attraction force between the magnet rotor 4 and A, 6B, 6C, 6D is maintained. Hereinafter, similarly, (c) of FIG.
As shown in (d), the magnetic poles of the respective stator end portions 7 are sequentially switched alternately with the rotation of the magnet rotor 4,
Braking on the magnet rotor 4 is continued.

The magnitude of the braking force acting on the rotating shaft 3 is determined by the magnitude of the magnetic repulsive force and the attractive force generated between the magnetic pole of each stator end 7 and the magnetic pole on the magnet rotor 4. The size can be freely changed regardless of the rotation speed of the magnet rotor 4 by changing the magnetic field strength of the magnetic pole of each stator end 7. The magnetic field strength of the magnetic poles of each stator end 7 can be controlled by the magnitude of the exciting current or the duty ratio of the exciting pulse or the magnitude of the exciting voltage flowing through the exciting coil 9 provided in each stator 6.

That is, the magnitude of the braking force acting on the rotating shaft 3 is determined by the magnetic field strength setting means 23 described above.
Can be controlled by controlling the magnitude of the exciting current flowing through each exciting coil 9 or the duty ratio of the exciting pulse to an appropriate value in accordance with the operation amount of. Therefore,
When used as a vehicle brake device, the magnitude of the generated braking force can be controlled over a wide range, and can be used as a service brake.
Further, in the configuration in which the stator 6 equipped with the excitation coil 9 is arranged around the magnet rotor 4 that rotates integrally with the rotating shaft 3, the configuration of the device is very simple compared to a fluid type retarder or the like, and the device is compact. Also, a large braking force can be obtained even in a low speed range.

In the electromagnetic brake device according to the present invention, the number of stators equipped with exciting coils and the number of exciting coils are not limited to the above embodiment.
It can be changed to any number.

The electromagnetic braking device according to the present invention can also function as an electric motor by controlling the magnetic poles of each stator end 7 so as to apply a rotating force to the magnet rotor. When installed in an electric vehicle or the like, it can also function as a drive motor for traveling. In addition, the use as a brake device is not limited to a vehicle, but can be widely used for braking a rotating shaft in a general industrial machine.

Further, in the case of the electromagnetic braking device according to the present invention, the generated braking force is controlled by controlling the exciting current and the duty ratio of the exciting pulse by the magnetic field strength setting means 23 provided in the control circuit 16. The number of stators 6 and the number of exciting coils 9 can be adjusted according to the weight and running performance of the vehicle when used as a vehicle brake device.
By changing the number of turns, good braking performance can be exhibited for various types of vehicles.

Incidentally, in the case of the electromagnetic brake device according to the present invention, it is possible to determine whether the vehicle is moving forward or backward without using the rotation detecting means 14. That is, in FIG. 1, when the direction of the arrow is the time of forward movement of the vehicle and the opposite direction is the time of backward movement of the vehicle,
FIG. 3A shows the magnetic pole detection by the magnetic pole sensors 11 and 12.
(B). The detection time interval T ₁ from the magnetic pole sensor 11 to the magnetic pole sensor 12 and the detection time interval T ₁ from the magnetic pole sensor 12 to the magnetic pole sensor 11
T ₂ compared by the control circuit 6 and a detection time interval T ₂ of the
> In the case of T ₁ is determined that the vehicle advances, in the case of T _1> T ₂ determines that the vehicle backward. Further, a stator and an exciting coil may be arranged on the side surface of the magnet rotor, and the magnet rotor is formed into an annular column, and a stator,
An excitation coil may be provided.

[0022]

According to the electromagnetic brake device of the present invention,
When the magnetic pole sensor detects the magnetic pole on the outer periphery of the magnet rotor, the energizing polarity setting means determines the energizing polarity of the exciting coil on each stator based on the signal from the rotation detecting means, and magnetic repulsion between the magnet rotor and each stator. By generating the force and the suction force, a braking force for suppressing rotation is generated. In this way, by applying magnetic repulsive force and attractive force from the ends of all the stators arranged around the magnet rotor in a direction opposite to the rotation direction of the magnet rotor, the rotating shaft to which the magnet rotor is connected Is braked. The magnitude of the braking force generated on the rotating shaft is determined by the magnitude of the magnetic force generated between the magnetic pole at the end of each stator and the magnetic pole on the magnet rotor. The magnitude of the magnetic force is determined by changing the magnetic field strength of the magnetic pole at each stator end. The magnetic field strength of the magnetic pole at each end of the stator can be controlled by the magnitude of the exciting current or the duty ratio of the exciting pulse flowing through the exciting coil provided in each stator. That is, the magnitude of the braking force generated on the rotating shaft is controlled by controlling the magnitude of the exciting current or the duty ratio of the exciting pulse applied to each exciting coil to an appropriate value by the magnetic field strength setting means, so that the low-speed range of the vehicle can be controlled. However, a large braking force can be obtained. In addition, around the magnet rotor that rotates integrally with the rotating shaft,
With a configuration in which a stator equipped with an excitation coil is arranged, the configuration of the device is very simple as compared with a fluid type retarder or the like, and is suitable for making the device compact. The brake device according to the present invention is used not only as a service brake but also as an auxiliary brake device.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an electromagnetic brake device according to the present invention.

FIG. 2 is an operation explanatory diagram of the electromagnetic brake device according to the embodiment of the present invention.

FIG. 3 is a principle diagram for determining whether the vehicle is moving forward or backward according to another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electromagnetic force braking device 3 rotating shaft 4 magnet rotor 6A to 6D stator 7 stator end 9 exciting coil 11, 12 magnetic pole sensor 14 rotation detecting means 16 control circuit 18 brake pedal 20 pedal sensor 22 energizing polarity setting means 23 magnetic field strength setting means

Claims (2)

[Claims] A magnet rotor that rotates integrally with a rotating shaft; and a stator that is provided at a plurality of locations spaced circumferentially around the magnet rotor and at a fixed distance from the outer peripheral surface of the magnet rotor. An excitation coil that is provided for each stator and turns the end of the stator facing the magnet rotor into an N-pole or S-pole when energized, and a magnet rotor that is provided at an intermediate position between adjacent stators and passes through that position A magnetic pole sensor for detecting the magnetic pole of the magnetic pole sensor, and a control circuit for controlling energization to the exciting coil of each stator based on a detection signal of the magnetic pole sensor and a rotation direction of the magnet rotor, and the control circuit The magnetic pole at the end of the stator is controlled by an output signal of a magnetic pole sensor that detects the magnetic pole of the magnet rotor. An electromagnetic force braking device comprising: a current-carrying polarity setting unit that performs the control. 2. The electromagnetic force braking device according to claim 1, wherein said control circuit includes a magnetic field strength setting means for controlling a magnetic field strength of said end portion of said stator.