JP3029697B2 - Translation type magnetic damper device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic damper device for attenuating the vibration of various devices and applying a load to the motion, and more specifically, a so-called magnetic damper device in which the relative movement direction between a conductor plate and a magnet is linear. The present invention relates to an improvement of a translation type magnetic damper device.

[0002]

2. Description of the Related Art A magnetic damper device of this type is disclosed in the literature, for example, “Transactions of the Japan Society of Mechanical Engineers, No. 890.
−26 ”provides the theoretical basis.
FIGS. 4A and 4B show a basic model of the conventional translational magnetic damper device. The magnetic damper device in the figure has yokes 1 and 2 having one end connected in a U-shape and the other end facing up and down, and arranged on upper and lower opposing surfaces of the yokes 1 and 2, respectively. The permanent magnet includes opposing permanent magnets and a conductor plate arranged in a non-contact state in a gap having a high magnetic flux density in a magnetic circuit formed by the permanent magnets.

In the above configuration, when the conductor plate 5 relatively moves in the direction of the arrow at a predetermined speed v, the magnetic flux in the gap d is cut off, so that an electromotive force E is induced in the conductor plate 5, and as a result, FIG. An eddy current flows as indicated by a chain line in (). This eddy current causes the conductor plate 5 to generate a braking force in the direction opposite to the moving direction by the action of the magnetic field.

[0004] This damping force attenuates the vibration of various devices and structures (not shown) connected to the conductor plate 5 or the yokes 1 and 2 sides, or when a load is applied to the movement, the damping force is extremely reduced to the movement speed. It has the advantages of being directly proportional, being stable and acting without contact, and having little change with respect to temperature.
In addition to being used for high-precision positioning of the table device disclosed in Japanese Patent Application Laid-Open No. 1-2005, it can be applied to various uses. As shown in the above publication, the magnets 3 and 4, that is, the yokes 1 and 2 are usually immovably fixed, and the conductor plate 5 is fixed between the fixed magnets 3 and 4 in a desired linear direction. Movably forward and backward.

[0005]

However, the conventional translational magnetic damper has the following problems. That is, when the conductor plate 5 moves, the braking force received by the conductor plate 5 is proportional to the moving speed v of the conductor plate 5, proportional to the square of the magnetic field generated by the permanent magnets 3, 4, and Although the resistance of the conductor plate 5 is inversely proportional to the resistivity of the conductor plate 5, the braking force is proportional only to the moving speed because the strength of the magnetic field and the resistivity of the conductor plate 5 are constant. Become.

Accordingly, when the magnetic damper device is connected to various devices and used as a vibration damping device for preventing the vibration of the device, the vibration applied to the device has various relative moving speeds at the time of vibration. There is, but besides that,
Since there are various vibration magnitudes (amplitudes) and vibration frequencies, there is ultimately a vibration damping force for a specific vibration magnitude (amplitude) and vibration frequency. I could not control the vibration efficiently.
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and in this type of translational damper device, there is provided a translational magnetic damper device capable of reliably damping and damping vibrations of different amplitudes and frequencies. It is intended to be.

[0007]

In order to achieve the above object, a translation type magnetic damper device according to the present invention includes a magnetic circuit constituted by disposing permanent magnets on one or both of opposing surfaces of a yoke. A magnetic damper device having a conductor arranged in a non-contact state in a gap having a high magnetic flux density of the magnetic circuit, and a conductor relatively moving with the permanent magnet in a substantially linear direction for cutting off a magnetic flux generated from the permanent magnet. And at least one of the permanent magnet and the conductor can be moved in a direction different from the direction in which the relative movement is performed.

[0008]

In the translation type magnetic damper device having the above structure, at least one of the conductor and the permanent magnet is moved relative to the conductor plate and the permanent magnet for exerting the actual braking force by using electromagnetic induction. Move in a different direction. Then, the relative positional relationship between the permanent magnet and the conductor changes, the amount of eddy current flowing changes, and the area of the high magnetic flux density region on the conductor (the overlapping area of the permanent magnet and the conductor) changes. As a result, the magnitude of the braking force determined by the eddy current and the strength of the magnetic field in the high magnetic flux density region changes. Therefore, by adjusting the amount of movement in the different directions, effective vibration suppression and braking are performed according to the amplitude and frequency of various vibrations.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a translation type damper device according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a front view showing an example of such a damper device, and FIG. 2 is a plan view thereof.

As shown in FIG. 1, a pair of permanent magnets 14 (N-pole) and 16 (S-pole) having different polarities are provided on both opposing surfaces of upper and lower yokes 10 and 12 having one end connected in a U-shape. Are respectively opposed to each other, and the respective permanent magnets 1
A magnetic circuit is formed between the magnetic poles 4 and 16 by the magnetic field from the north pole to the south pole indicated by the arrow in the figure. In the gap d having a high magnetic flux density of the magnetic circuit, a conductor plate 22 made of a non-magnetic material, which is a good electrical conductor such as an aluminum plate in a non-contact state, is arranged.

The conductor plate 22 includes a rectangular moving body 24.
It is attached to one side in a horizontal protruding state,
The bottom surface of the moving body 24 is slidably connected to the first rail 26 so that it can move forward and backward along the first rail 26. Then, the first side surface of the moving body 24 is
The screw bearing member 28 of the first stepping motor 30 having a screw thread is screwed to the first screw bearing member 28. Thus, when the first stepping motor 30 is rotated forward and reverse, the rotation force is increased by the first stepping motor 30.
The first rail 2 is connected to the moving body 24 via the screw shaft 32 and the first screw bearing member 28 as the output shaft of the first rail 2.
6 as a propulsive force in the straight running direction.

In the present invention, the pair of permanent magnets 1
4, 16 (magnetic circuit) can be moved back and forth in a direction orthogonal to the moving direction of the moving body 24. Specifically, a second rail 34 extending in a direction orthogonal to the first rail 26
Is disposed on the second rail 34 of the lower permanent magnet 1.
The bottom surface of the yoke 12 to which the reference numeral 6 is attached is slidably connected. As a result, the yoke 10 integrated with the yoke 12 and the two permanent magnets 14 and 16 can move forward and backward along the second rail 34.

Further, in this embodiment, a second screw bearing member 36 is arranged to protrude from a rear portion of the side surface of the yoke 12, and the second screw bearing member 36 has a screw shaft 40 of a second stepping motor 38 having a screw screw. Is screwed. Thus, for the same reason as the operation principle of the moving body 24, the yoke 12, that is, the yoke 10 and the two permanent magnets 14 and 16 are moved along the second rail 26 by rotating the second stepping motor 38 in the normal and reverse directions. To move forward and backward.

In the above configuration, after the first stepping motor 30 is rotated to move the moving body 24, that is, the conductor plate 22 in a predetermined direction, and then stops moving, the conductor plate 22 will continue to move due to inertial force. Where vibration occurs. Now, for the sake of convenience, as shown in FIG. 3A, which is viewed from the same direction (upper direction) as FIG. 2, if the conductor plate 22 is going to move in the direction of arrow A, the conductor plate 2
2 cuts off the magnetic flux in the gap d, the electromotive force E is induced in the conductor plate 22 by Fleming's right-hand rule, and an eddy current flows in a predetermined direction as shown by a solid line. On the other hand, although not shown, when the conductor plate 22 moves in the opposite direction due to the vibration of the conductor plate 22, the direction of the eddy current generated on the conductor plate 22 also becomes the opposite direction, thereby causing The braking force is also reversed. Therefore, when the conductor plate 22 is about to vibrate, the eddy current causes a braking force in the direction opposite to the moving direction on the conductor plate 22 by the action of the magnetic field,
A load is applied to the damping and movement of the vibration of the moving body 24 connected to the conductor plate 22.

Incidentally, some of the above-mentioned vibrations have various amplitudes and frequencies. Therefore, in the present embodiment, the second
By rotating the stepping motor 38 in a predetermined direction to move the yokes 10, 12, that is, the permanent magnets 14, 16 forward and backward in a direction orthogonal to the moving direction of the conductive plate 22, the permanent magnets 14, 16 are moved. The relative positional relationship between the vibration and the conductor plate 22 is made different, so that effective vibration suppression can be performed in accordance with the amplitude and frequency of such various vibrations.

That is, when the permanent magnet 16 (14) is moved in the direction of arrow B from the state shown in FIG.
As shown in the figure, the permanent magnet 16 (14)
2 near one side edge. In this state, when the conductor plate 22 moves in the direction of arrow A, the conductor plate 2
2, an eddy current as shown by a solid line on the conductor plate 22 is generated. At this time, the eddy current flowing toward one side edge of the conductor plate 22 reaches the side edge, and the current flows further outside. Therefore, the course is forcibly bent there, and the flow path resistance increases. As a result, it becomes difficult for the current to flow, and the braking force generated by the eddy current and the magnetic field also decreases.

When the permanent magnet 16 (14) further moves in the direction of arrow B from the state shown in FIG.
As shown in FIG. 3, a part of the permanent magnet 16 (14) is
2 to the outside. Then, according to the same principle as that of FIG. 2B, not only the flowing eddy current is reduced, but also the high magnetic flux density region on the conductor plate 22 which is the strength of the magnetic field that contributes to the final determination of the magnitude of the braking force. (Approximately equal to the projected portion of the permanent magnet 16 (14) on the conductive plate 22) is reduced, so that the braking force is further reduced.

From this state, the permanent magnet 1
By moving 6 (14) in the direction of arrow B, the high magnetic flux density area on the conductor plate 22 is further reduced as shown in FIG. 4D, and the braking force is further reduced as compared to FIG. 4C.

As described above, the second stepping motor 3
The braking force can be adjusted by rotating the yokes 10 and 12, that is, the permanent magnets 14 and 16 by rotating the motor 8 forward and backward. Therefore, by changing the relative position between the permanent magnets 14 and 16 and the conductor plate 22 according to the amplitude and frequency of the vibration to be damped, vibration damping against various vibrations can be improved.
Braking becomes possible.

The movement of the conductor plate 22 for exerting the braking force and the movement of the permanent magnets 14 and 16 for adjusting the braking force are performed separately at different times. Alternatively, the permanent magnets 14 and 16 may be moved at the same time while the conductor plate 22 is moving.

In the above-described embodiment, a braking force is generated when the conductive plate 22 is moved, and the braking force can be adjusted when the permanent magnets 14 and 16 are moved. However, the present invention is not limited to this, and the arrangement may be reversed, and only one of them may be movable in the above two directions. .

In the above-described embodiment, the moving body 24 to which the conductor plate 22 is attached is moved in a predetermined direction by the first stepping motor 30 like the positioning of the table device, and then the moving direction generated when the moving body 24 is stopped. However, the present invention can be applied to, for example, a computer or any other device that dislikes vibration, to operate the device itself, or to cause vibration of the device due to shaking of the surroundings. Or to reduce
The present invention can be applied to various fields such as a vibration damping device for suppressing vibration of a building caused by an earthquake or other causes.

The means for varying the relative positional relationship between the permanent magnets 14, 16 and the conductor plate 22 for controlling the braking force is not limited to the above-described stepping motor, but may be determined according to the size of the object. It is determined as appropriate. The driving mechanism is not limited to a motor or other electric type as in the above-described embodiment, but may be of various types such as a mechanical type such as a cylinder, a gear, and a link, and a manual type.

Further, in each of the above embodiments, an example was described in which a metal electrical good conductor such as an aluminum plate was used as the conductive plate 22, but the present invention is not limited to this. A good electrical conductor may be used, and the present invention is not limited to a solid and may be a liquid. However, in the case of a liquid, it goes without saying that a predetermined case (either a conductor or a non-conductor) for accommodating the liquid is required.

[0025]

As described above, in the translation type magnetic damper device according to the present invention, at least one of the conductor and the permanent magnet is provided with a conductor plate for exerting an actual braking force using electromagnetic induction. Because it is possible to move in a direction different from the direction of relative movement with the permanent magnet, the relative movement changes the relative positional relationship between the permanent magnet and the conductor, changing the amount of eddy current flowing in the conductor and the high magnetic flux on the conductor The density region can be varied. As a result, the magnitude of the braking force determined by the eddy current and the strength of the magnetic field in the high magnetic flux density region can be controlled. By adjusting the relative movement amounts in the different directions, the amplitude of various vibrations can be controlled. Effective damping and braking can be performed according to the frequency.

[Brief description of the drawings]

FIG. 1 is a front view showing a preferred embodiment of a translational magnetic damper device according to the present invention.

FIG. 2 is a plan view of the translational magnetic damper device shown in FIG.

FIG. 3 is a diagram for explaining the operation of the present embodiment.

FIG. 4A is a front view showing a basic model of a translation type magnetic damper device. (B) is an explanatory view showing a state of occurrence of an eddy current when the conductor plate is moved.

[Explanation of symbols]

 10, 12 Yoke 14, 16 Permanent magnet 22 Conductor plate

Continuation of front page (72) Inventor Hirofumi Nakano 5-36-11 Shimbashi, Minato-ku, Tokyo Inside Fuji Electric Chemical Co., Ltd. (56) References JP-A-61-131841 (JP, A) JP-A-63- 312536 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16F 15/03

Claims (1)

(57) [Claims] 1. A magnetic circuit constituted by disposing permanent magnets on one or both of opposing surfaces of a yoke; and a magnetic circuit having a high magnetic flux density disposed in a non-contact state with the permanent magnet. In a magnetic damper device including a conductor that relatively moves with the permanent magnet in a substantially linear direction that cuts off a generated magnetic flux, it is possible to move at least one of the permanent magnet and the conductor in a direction different from the direction in which the relative movement is performed. A translation type magnetic damper device.