JP3038347B2 - Dynamic vibration absorber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device for a structure, and relates to a dynamic vibration absorber which can respond to vibration in a two-dimensional horizontal direction by using one movable weight and can obtain a vibration effect regardless of the direction. .

[0002]

2. Description of the Related Art A conventional dynamic vibration absorber is configured to specify a vibration direction of a structure to be damped and to vibrate an additional weight so as to exert a vibration damping effect in that direction. When there are a plurality of vibration directions to be damped, it is necessary to install the dynamic vibration absorbers in a number corresponding to each direction.

[0003] FIG. 23 schematically shows the installation direction of a conventional dynamic vibration absorber. In FIG. 23, a plurality of dynamic vibration absorbers having a supporting structure 1a supported via a rigid element 3 and a damping element 4 in parallel with an additional weight 2 are installed in accordance with the vibration direction of the structure 1 to be damped. ing. When the installation space for the dynamic vibration absorber can be sufficiently secured, as in a large structure such as a building structure, there is no problem in installing a plurality of dynamic vibration absorbers.

[0004]

In the above configuration,
Like a mechanical structure, the installation space for the dynamic vibration absorber is limited,
Moreover, when vibration damping in multiple directions is required, it is difficult to perform appropriate arrangement setting for obtaining a vibration damping effect with the conventional structure in which the vibration direction of the added weight is constant.

The present invention has been made on the basis of the above points, and in particular, when a structure to be damped vibrates in a horizontal two-dimensional direction, one movable weight can be vibrated in any horizontal two-dimensional direction. An object of the present invention is to provide a dynamic vibration absorber supported so as to be able to follow.

[0006]

In order to achieve the above object, according to the first aspect of the present invention, a movable weight portion serving as a vibration absorber and adjacent cylindrical magnets installed in the movable weight portion are alternately different. A movable portion magnet row having magnets of magnetic poles and arranged concentrically, a fixed portion provided opposite to the movable weight portion, and a cylindrical magnet on the movable weight portion side in a stationary state on the fixed portion side And a fixed part magnet row in which magnets of different magnetic poles are respectively arranged at positions opposed to the movable weight part and the fixed part. A conductor plate is fixed to the fixed portion between the movable portion magnet row and the fixed portion magnet row, and the conductor plate is provided to be larger than the outermost circle formed by the fixed portion magnet row. A dynamic vibration absorber comprising:

[0007]

[0008]

[0009]

According to a second aspect of the present invention, there is provided a mechanism for adjusting a gap between the movable section magnet row and the fixed section magnet row, and the mechanism for adjusting the gap fixes the movable section magnet row or the fixed section magnet row. A yoke having a fitting structure capable of moving up and down with the movable weight portion or the fixed portion to which the yoke is attached; a plurality of bolts formed integrally with the yoke and inserted through the movable weight portion or the fixed portion; A nut provided on a part or a fixing part side to fix the bolt,
A dynamic vibration absorber having a female screw portion provided on the movable weight portion or the fixed portion side, a push screw fitted to the female screw and abutting on the yoke, and a nut for fixing the push screw.

According to a third aspect of the present invention, there is provided a mechanism for adjusting a gap between the movable section magnet row and the fixed section magnet row, and the mechanism for adjusting the gap fixes the movable section magnet row or the fixed section magnet row. A yoke having a fitting structure capable of moving up and down with the movable weight portion or the fixed portion to which the yoke is attached; a bolt formed integrally with the yoke and inserted through the movable weight portion or the fixed portion; Provided is a dynamic vibration absorber having a female screw portion provided on a fixing portion side and fitted to the bolt, and a nut for fixing the bolt.

According to a fourth aspect of the present invention, the movable weight portion is replaced with a movable portion magnet row in which adjacent cylindrical magnets provided in the movable weight portion have magnets of different magnetic poles alternately and are arranged concentrically. A movable magnet comprising the provided rectangular magnet and four peripheral magnets which are horizontally adjacent to the four pieces of the magnet at a predetermined distance from each other and have the magnet and four peripheral magnets having anisotropic poles In addition to the fixed part magnets having magnets of different magnetic poles each having a magnet row, the magnets having different magnetic poles are arranged at positions opposed to the cylindrical magnets on the movable weight part side in a stationary state on the fixed part side, There is provided a dynamic vibration absorber having a stationary part magnet row in which magnets of different magnetic poles are arranged at positions opposed to a movable part magnet row composed of the rectangular magnet and four peripheral magnets in a stationary state.

According to a fifth aspect of the present invention, instead of a magnet array of concentrically arranged movable magnets in which adjacent cylindrical magnets which are provided in a movable weight portion and have magnets of different magnetic poles alternately, are intermittently connected to the movable portion. A movable part magnet row in which magnets of different magnetic poles are alternately arranged on adjacent magnets that are arranged concentrically and further, the cylindrical magnet on the movable part weight part side in a stationary state on the fixed part side, and Instead of the fixed part magnet row in which magnets of different magnetic poles are arranged at opposing positions, different magnetic poles are respectively arranged at positions facing the movable part magnet rows intermittently and concentrically arranged in a stationary state on the fixed part side. The present invention provides a dynamic vibration absorber having a fixed part magnet row in which magnets are arranged.

According to a sixth aspect of the present invention, a magnet having a different magnetic pole is provided adjacent to the movable weight portion in the circumferential direction, and a magnet having a different magnetic pole is provided adjacent to the fixed portion in the circumferential direction. Further, the present invention provides a dynamic vibration absorber in which the magnet provided on the fixed portion side and the magnet provided on the movable weight portion side are arranged so as to face each other with different magnetic poles.

[0015]

[0016]

In the dynamic vibration absorber having the above-mentioned structure, according to the first aspect of the present invention, when the movable weight portion moves from the stationary position, that is, when the opposed magnet is displaced in the horizontal direction, the movable weight portion is opposed at the stationary position. Attraction between the different magnetic poles causes a repulsive force while approaching the same magnetic pole adjacent thereto. Each of these acts as a restoring force for returning the moving amount of the movable weight portion to the movement in the horizontal arbitrary direction. Further, the magnetic flux passing through the conductor plate provided between the opposed magnets moves relative to the conductor plate with the movement of the movable weight portion, and this acts as a magnetic damping force due to eddy current loss generated in the conductor plate.

Further, according to the invention described in claim 2, according to claim 1
When the movable weight portion moves from the rest position in the same manner as the described invention, both the attractive force acting between the different magnetic poles and the repulsive force acting by approaching the same adjacent magnetic pole are two-dimensional movements in any direction. On the other hand, it acts as a restoring force that restores the moving amount of the movable weight part, and a magnetic damping force acts due to the relative movement with the conductor plate accompanying the movement of the movable weight part. In order to obtain a constant spring constant and a constant damping coefficient as a dynamic vibration absorber by these forces, the movable weight part and the fixed part are connected by laminated rubber, and the gap between the opposed magnets is kept constant.

According to the third, seventh or eighth aspect of the present invention, the movable part magnet row or the fixed part magnet row is vertically moved and fixed, and the gap between the opposed magnets can be adjusted. Thereby, the magnetic spring constant can be made variable.

According to the fourth aspect of the present invention, the effect of solid friction is reduced as much as possible by directly sandwiching a hard sphere between the movable weight portion and the fixed portion to transmit the load, and the bearing structure is compact and has a high load resistance. Is obtained.

According to the fifth and sixth aspects of the present invention, the clearance between the opposed magnets can be adjusted by allowing the receiving seat of the hard sphere to move up and down. According to the ninth aspect of the invention, by changing the aspect ratio of the rectangular magnet, the magnetic spring constant depending on the direction can be changed, and it is possible to cope with anisotropic two-dimensional vibration.

According to the tenth aspect of the present invention, even when the outer magnet is divided into circumferential positions, the magnetic spring characteristics and the magnetic damping characteristics can be obtained as in the case of the integral multi-structure magnet. According to the eleventh aspect of the present invention, a repulsion that acts as the inner magnet approaches the outer magnet can be provided by providing a defect in the circumferential position of the outer magnet or the inner magnet, changing the magnet thickness, or partially adding a magnet. The magnitude of the force will change depending on the direction. By utilizing this, the restoring force characteristic (magnetic spring constant) can be adjusted depending on the direction.

According to the twelfth aspect of the present invention, particularly when the multi-structure magnet has a circular shape, there is no restraining force in the torsion direction. Can be prevented. Claim 1
According to the third aspect of the present invention, since the main body is housed in the housing, the main body can be shielded from the outside air, and foreign matters do not adhere to the main body, so that the durability can be improved.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a dynamic vibration absorber according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view showing a first embodiment of the dynamic vibration absorber according to the present invention, and FIG. 2 is a transverse sectional view taken along the line AA of FIG. In the present invention, a multi-structure magnet in which adjacent movable portion inner magnets 6 and movable portion outer magnets 7 have different magnetic poles is added to the movable weight 5 of the dynamic vibration absorber via a yoke 8 made of a magnetic material. It is fixed. Here, one set of the movable portion inner magnet 6, the movable portion outer magnet 7, and the yoke 8 is collectively referred to as a movable portion magnet array 9. A multi-structured magnet having a different magnetic pole opposed to the movable part magnet row 9 is installed via the yoke 33 in a stationary state also on the vibration suppression target structure 1 facing this. That is, when the movable portion inner magnet 6 has the N pole, the fixed portion inner magnet 10 at the opposing position has the S pole, the movable portion outer magnet 7 has the S pole, and the fixed portion outer magnet 11 has the N pole. Here, a set of the fixed portion inner magnet 10, the fixed portion outer magnet 11, and the yoke 33 is collectively referred to as a fixed portion magnet row 12. The movable part magnet row 9 and the fixed part magnet row 12 are installed with a constant gap 13 up and down. This is because the movable weight 5 and the receiving seats 14a and 34 fixed to the vibration damping target structure 1 respectively. This is ensured by directly sandwiching a plurality of hard spheres 15 through the intermediary. Further, the conductor plate 16 is provided in the gap 13 so as not to be in contact with the magnet. The conductor plate 16 may be fixed to any of the damping target structure 1 and the movable weight 5, and may be in contact with the fixed side magnet. A stopper block 17 is provided around the movable weight 5 in order to prevent deviation due to excessive vibration. Although a double cylindrical magnet is shown here as the multi-structure magnet, a plurality of magnets may be arranged concentrically. This embodiment will be described later as an eighth embodiment with reference to FIG.

The dynamic vibration absorber described above is composed of the fixed part magnet row 12
And the like are incorporated into a part of the structure 1 to be damped. However, as in the second embodiment shown in FIG. If the system is fixed to the structure 1 to be damped, the weight increases, but the attachment and detachment to the structure 1 to be damped becomes simple, and a versatile dynamic vibration absorber can be obtained.

Further, since all the movable parts are surrounded by the housing 18, foreign matters such as powders do not enter the movable parts even in an atmosphere of vapor, powder, etc., thereby preventing a problem from occurring. As described above, in the embodiment illustrated in FIGS. 1 and 3, the case where the dynamic vibration absorber is installed on the upper surface of the target structure is shown. However, the dynamic vibration absorber is installed on the lower surface or the side surface of the target structure with the same configuration. be able to.

In FIG. 4, it has been experimentally confirmed that the magnetic spring constant (the gradient of the load-displacement relationship) can be adjusted by changing the gap δ between the opposed magnets. Here, a 2-17 series rare earth cobalt magnet (maximum magnetic energy product: 26 MGOe, residual magnetic flux density: 1.02 T) was used as the magnet, the yoke material was SUS403, and the thickness was 10 mm. In FIGS. 5 and 6, it has been experimentally confirmed that the attenuation of the dynamic vibration absorber can be largely adjusted by changing the thickness t of the conductor plate. Here, the conductor plate is a copper plate (C1100P)
It was used. Further, in FIG. 7, it was confirmed that the presence or absence of the conductor plate did not significantly affect the magnetic resilience characteristics.
It can be seen that the magnetic restoring force and the magnetic damping force of the dynamic vibration absorber according to the present invention can be handled independently.

FIGS. 8 (a) and 8 (b) show a third embodiment of the present invention, in which the movable part outer magnets 7 and / or the movable part magnet rows 9 and / or the fixed part magnet rows 12 are provided. In the fixed portion outer magnet 11, the missing portion 20 depends on the circumferential position.
And the thickness of the magnet is changed. The magnetic spring constant can be adjusted depending on the direction, which can cope with the case where the structure to be damped has anisotropy. As another embodiment of the magnet array, as shown in FIG. 9, in the movable part outer magnet 7 and the fixed part outer magnet 11, the magnetic spring constant is changed depending on the direction by partially providing the additional magnet 21 at the circumferential position. Can be adjusted. Further, FIG.
, An additional magnet 21 is provided for the movable portion inner magnet 6 and the fixed portion inner magnet 10. Therefore, similarly to FIG. 9, the horizontal magnetic spring constant of the movable portion inner magnet 6 and the fixed portion inner magnet 10 can be adjusted.

Further, as a fourth embodiment of the present invention, when the vibration direction is determined to be two orthogonal directions, as shown in FIG.
3 may be configured as the movable section magnet row 9 and the fixed section magnet row 12. In this case, manufacturing is easy because of the rectangular shape, and since each is separated, horizontal adjustment can be adjusted by the force and position of the magnet.

FIG. 12 shows a fifth embodiment of the present invention, in which a plurality of hard spheres 15 are directly sandwiched between receiving structures 14a and 34 provided on the structure 1 to be damped and the movable weight 5. However, the relative positions of the hard balls 15 are kept constant by a retainer 24 which is integrally formed in a circumferential shape. here,
The retainer 24 has a tapered contact surface 25 with the hard sphere 15, and is divided into upper and lower parts, fixed by bolts 26 and nuts 27, and integrally formed over the entire circumference. Although the weight of the retainer 24 is configured to be added to the hard sphere 15,
A bearing for supporting the weight of the retainer 24 may be separately provided on the retainer 24. The retainer 24 is shown as an example in which the upper part and the lower part are integrated, but the upper part alone may move upward. However, the retainer 24 can be used in normal times because the upward movement is small.

FIG. 13 shows a sixth embodiment of the present invention, in which the receiving seat 14a of the rigid ball 15 is fitted to the movable weight 5, and moves up and down along a slide surface 28 formed on the movable weight 5. It is possible. And it has the structure fixed to the movable weight 5 by the screw part 29 and the nut 30 arranged above the receiving seat 14a. Thereby, the gap δ between the opposed magnets can be adjusted. Further, a similar structure may be provided on the fixed portion side to move the receiving seat 34.

Further, as another embodiment of the rigid ball seat, when the thickness of the hard ball seat is changed, or when the receiving seat 14a is fixed to the movable weight 5 as shown in FIG.
The gap δ between the opposed magnets can be adjusted by tightening the pinch 1 with the pinching bolt 32 and changing the thickness of the liner 31. It should be noted that the liner 31 may be provided on the receiving seat on the side of the structure 1 to be damped.

Next, a seventh embodiment of the dynamic vibration absorber according to the present invention will be described with reference to FIGS. FIG. 15 is a longitudinal sectional view of the dynamic vibration absorber according to the present embodiment, and FIG. 16 is a transverse sectional view. In the present invention, a multi-structure magnet in which the movable portion inner magnet 6 and the movable portion outer magnet 7 adjacent to the movable weight 5 of the dynamic vibration absorber have mutually different magnetic poles is installed via a yoke 33 made of a magnetic material. ing. That is, when the movable portion inner magnet 6 has an N pole, the fixed portion inner magnet 10 has an S pole, the movable portion outer magnet 7 has an S pole, and the fixed portion outer magnet 11 has an N pole. Here, the fixed portion inner magnet 10 and the fixed portion outer magnet 1
1. One set of the yoke 33 is generally referred to as a fixed part magnet row 12. The movable part magnet row 9 and the fixed part magnet row 12 are installed with a constant gap 13 up and down.
A plurality of laminated rubbers 35 are installed via mounting seats 14b respectively fixed to the vibration damping target structure 1 and secured by connecting the two. Further, the conductor plate 16 is provided in the gap 13 so as not to contact the magnet. The conductor plate 16 may be fixed to any of the damping target structure 1 and the movable weight 5, and may be in contact with the fixed side magnet. Although a double cylindrical magnet is shown here as the multi-structure magnet, the magnet may be arranged in a plurality of cylindrical shapes.

Next, an eighth embodiment of the dynamic vibration absorber according to the present invention will be described with reference to FIG. In the dynamic vibration absorber of the seventh embodiment, the multi-structure magnet has a double cylindrical integral structure. In the eighth embodiment, the outer magnet 37 divided into a plurality around the inner magnet 36 around the circumference. Are arranged to form a multi-structure magnet. here,
If the outer magnet 37 is arranged symmetrically with respect to the inner magnet 36, the same magnetic spring constant can be obtained regardless of the direction. By changing the installation distance from the center of the outer magnet 37 depending on the direction, the magnetic spring constant according to the direction can be obtained. Can be adjusted.

A ninth embodiment of the dynamic vibration absorber according to the present invention will be described with reference to FIG. In the ninth embodiment, a multi-structure magnet is configured by arranging an outer rectangular magnet 39 around an inner rectangular magnet 38. By adjusting the aspect ratio of the inner rectangular magnet 38 and making the adjacent facing surface of the adjacent outer rectangular magnet 39 equal to the length and width of the inner rectangular magnet 38, the magnetic spring constant can be adjusted depending on the direction.

FIG. 19 shows that the magnetic spring constant can be adjusted depending on the direction by changing the aspect ratio of the rectangular magnet. In addition, it can be seen from the figure that even if the spring constant is changed by changing the shape in the Y direction, it does not affect the X direction, and the magnetic spring constant can be handled independently depending on the direction.

A tenth embodiment of the dynamic vibration absorber according to the present invention will be described with reference to FIG. In this embodiment, the movable weight 5 for attaching the movable section magnet array 9 and the yoke 3
3 is provided with a fitting portion 40 which can be moved up and down, and a bolt 41 which is integral with the yoke 33 is provided with a movable weight 5.
Screw 45 which passes through the penetrating portion 42 provided on the movable weight 5, is fixed by the nut 43, and further passes through the female screw portion 44 provided on the movable weight 5.
Is pressed against the back surface of the yoke 33, and is fixed with a nut 46. As described above, the movable part magnet row 9 can be fixed after adjusting the gap between the opposed fixed part magnet row 12. In the present embodiment, the mounting portion of the movable portion magnet row 9 has been described. However, a similar configuration can be adopted when the fixed portion magnet row 12 is mounted on the structure 1 to be damped.

Next, an eleventh embodiment of the dynamic vibration absorber according to the present invention will be described with reference to FIG. In this embodiment,
A vertically movable fitting portion 40 is provided between the movable weight 5 to which the movable section magnet row 9 is attached and the yoke 33, and a bolt 47 formed integrally with the yoke 33 is passed through a female screw portion 48 provided on the movable weight 5, It is fixed with a nut 49. The movable section magnet row 9 can be fixed after the entire movable section magnet row 9 is moved up and down while being rotated, and the gap between the movable section magnet row 9 and the opposed fixed section magnet row 12 is adjusted. In the present embodiment, the mounting portion of the movable portion magnet row 9 has been described. However, a similar configuration can be adopted when the fixed portion magnet row 12 is mounted on the structure 1 to be damped.

Finally, a twelfth embodiment of the dynamic vibration absorber according to the present invention will be described with reference to FIG. In this embodiment, the peripheral magnets 50 adjacent to each other in the circumferential direction at the peripheral portion of the movable weight 5 form different magnetic poles, and the peripheral magnets 50 are fixed via the yoke 51. Peripheral magnets 52 having the same shape so that different magnetic poles face each other.
Are fixed via a yoke 53 and a pedestal 54. With the above configuration, it is possible to prevent the movable portion from moving in the twisting direction.

[0039]

As described above, according to the dynamic vibration absorber according to the present invention, the movable weight portion is supported by magnetic restoring force in any two-dimensional horizontal direction, and its spring constant is adjusted. As a result, the vibration damping effect can be obtained with one movable weight portion regardless of the direction. Further, by disposing the conductor plate between the opposing magnets, it can be used also as a magnetic damper, and all of the spring element and the damping element can be stored in the lower part of the movable weight part, so that the dynamic vibration absorber can be significantly reduced in size.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a dynamic vibration absorber according to the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a longitudinal sectional view of a dynamic vibration absorber according to a second embodiment of the present invention.

FIG. 4 is a characteristic diagram showing an influence between gaps of opposed magnets in a magnetic restoring force characteristic according to the present invention.

FIG. 5 is a diagram illustrating a frequency response curve of the dynamic vibration absorber when the conductor plate is changed according to the present invention.

FIG. 6 is a characteristic diagram showing an attenuation ratio of the dynamic vibration absorber according to the present invention in accordance with a change in a conductor plate.

FIG. 7 is a characteristic diagram showing the influence of a conductor plate on the magnetic restoring force characteristics according to the present invention.

FIG. 8 shows a third embodiment of the dynamic vibration absorber according to the present invention.
(A) is a cross-sectional view, (b) is a side view.

FIG. 9 is a cross-sectional view showing another embodiment of the magnet array of the present invention.

FIG. 10 is a cross-sectional view showing another embodiment of the magnet row of the present invention.

FIG. 11 is a cross-sectional view showing a fourth embodiment of the dynamic vibration absorber according to the present invention.

FIG. 12 is an enlarged side view showing a fifth embodiment of the dynamic vibration absorber according to the present invention.

FIG. 13 is a cross-sectional view showing a sixth embodiment of the dynamic vibration absorber according to the present invention.

FIG. 14 is an enlarged longitudinal sectional view showing another embodiment of a seat for a hard sphere according to the present invention.

FIG. 15 is a longitudinal sectional view showing a seventh embodiment of the dynamic vibration absorber according to the present invention.

FIG. 16 is a sectional view taken along the line BB of FIG. 15;

FIG. 17 is a transverse sectional view showing an eighth embodiment of the dynamic vibration absorber according to the present invention.

FIG. 18 is a transverse sectional view showing a ninth embodiment of the dynamic vibration absorber according to the present invention.

FIG. 19 is a characteristic diagram showing an influence of a magnet shape on a magnetic restoring force characteristic of the rectangular magnet according to the present invention.

FIG. 20 is a longitudinal sectional view showing a dynamic vibration absorber according to a tenth embodiment of the present invention.

FIG. 21 is a longitudinal sectional view showing an eleventh embodiment of the dynamic vibration absorber according to the present invention.

22A and 22B show a twelfth embodiment of the dynamic vibration absorber according to the present invention, wherein FIG. 22A is a longitudinal sectional view, and FIG.
FIG. 22 (c) is a view taken in the direction of the arrow D-D in FIG. 22 (a).

FIG. 23 shows a conventional example of a dynamic vibration absorber, where (a) is a side view,
(B) is a plan view.

[Description of Signs] 1 ... Structure to be damped 1a ... Supporting structure 2 ... Additional weight 3 ... Rigid element 4 ... Damping element 5 ... Moving weight 6 ... Moving part inner magnet 7 ... Moving part outer magnet 8 ... Yoke 9 ... Moving part magnet row 10 ... Fixed part inner magnet 11 ... Fixed part outer magnet 12 ... Fixed part magnet row 13 ... Gap 14a ... Receiving seat 14b ... Mounting seat 15 ... Hard ball 16 ... Conductor plate 17 ... Stopper block 18 ... Housing 19 ... Bolts 20: Defects 21: Additional magnets 22: Inner magnets 23: Outer magnets 24 ... Retainers 25 ... Contact surfaces 26 ... Bolts 27 ... Nuts 28 ... Sliding surfaces 29 ... Screws 30 ... Nuts 31 ... Liners 32 ... Bolts 33 ... Yoke 34 ... receiving seat 35 ... laminated rubber 36 ... inner magnet 37 ... outer magnet 38 ... inner rectangular magnet 39 ... outer rectangular magnet 40 ... fitting part 41 ... bolt 42 ... penetrating part 3 ... nut 44 ... female screw portion 45 ... pressing screws 46 ... nut 47 ... bolt 48 ... female screw portion 49 ... nut 50 ... near the magnet 51 ... yoke 52 ... near the magnet 53 ... yoke 54 ... base

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasushi Hattori 1 Koga Toshiba-cho, Saiwai-ku, Kawasaki City, Kanagawa Prefecture Inside the R & D Center (72) Inventor Katsuhiko Mawatari 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture (56) References JP-A-5-296286 (JP, A) JP-A-61-109935 (JP, A) JP-A-61-130642 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16F 15/02-15/08

Claims (6)

(57) [Claims] A movable weight portion serving as a vibration absorber; a movable portion magnet row in which adjacent cylindrical magnets installed in the movable weight portion are alternately arranged concentrically with magnets having different magnetic poles; A fixed portion provided opposite to the weight portion; and a fixed portion magnet row in which magnets having different magnetic poles are arranged at positions facing the cylindrical magnet on the movable weight portion in a stationary state on the fixed portion side. A hard sphere for securing the gap is provided between the movable weight portion and the fixed portion between the movable portion and the fixed portion. A dynamic vibration absorber characterized in that a conductor plate is fixed to a fixed portion, and the conductor plate is provided to be larger than an outermost circle formed by the fixed portion magnet rows. 2. A mechanism for adjusting a gap between the movable section magnet row and the fixed section magnet row. The mechanism for adjusting the gap includes a yoke for fixing the movable section magnet row or the fixed section magnet row. A plurality of bolts formed integrally with a yoke and inserted through the movable weight portion or the fixed portion, and a plurality of bolts formed integrally with the yoke, the movable weight portion or the fixed portion being attached to the movable weight portion or the fixed portion; A nut for fixing the bolt, a female screw portion provided on the movable weight portion or the fixed portion side, a push screw fitted to the female screw and abutting on the yoke, and a nut for fixing the push screw. The dynamic vibration absorber according to claim 1, comprising: 3. A mechanism for adjusting a gap between the movable section magnet row and the fixed section magnet row, the mechanism for adjusting the gap includes a yoke for fixing the movable section magnet row or the fixed section magnet row. A fitting structure that is vertically movable with the movable weight portion or the fixed portion to be attached; a bolt formed integrally with the yoke and inserted into the movable weight portion or the fixed portion; and a bolt provided on the movable weight portion or the fixed portion side The dynamic vibration absorber according to claim 1, further comprising a female thread portion fitted to the bolt, and a nut for fixing the bolt. 4. A rectangular magnet provided in the movable weight section instead of a concentrically arranged movable section magnet row in which adjacent cylindrical magnets provided in the movable weight section alternately have magnets of different magnetic poles. A movable part magnet array comprising a magnet and four peripheral magnets, which are horizontally adjacent to each other at a predetermined distance from the magnet and are disposed at a predetermined distance from each other and have the magnet and four peripheral magnets having anisotropic poles, is provided. Further, in place of the fixed part magnet in which magnets of different magnetic poles are respectively arranged at positions opposed to the cylindrical magnet on the movable weight part side in a stationary state on the fixed part side, the rectangular shape in the stationary part side is stationary. 2. The dynamic vibration absorber according to claim 1, further comprising a fixed part magnet row in which magnets having different magnetic poles are arranged at positions facing the movable part magnet row composed of the above-mentioned magnet and four peripheral magnets. 5. Instead of a row of concentrically arranged movable section magnets in which adjacent cylindrical magnets installed in the movable weight section have magnets of different magnetic poles alternately, they are intermittently concentric with the movable section. It has a movable part magnet row in which magnets of different magnetic poles are arranged alternately on adjacent magnets, and further, at a position facing the cylindrical magnet on the movable part weight part side in a stationary state on the fixed part side. In place of the fixed part magnet row in which magnets of different magnetic poles are arranged, magnets of different magnetic poles are arranged at positions opposed to the movable part magnet row intermittently and concentrically arranged in a stationary state on the fixed part side. The dynamic vibration absorber according to claim 1, further comprising a fixed part magnet row. 6. A magnet having a different magnetic pole provided adjacent to the movable weight portion in the circumferential direction and a magnet having a different magnetic pole provided adjacent to the fixed portion in the circumferential direction. 2. The dynamic vibration absorber according to claim 1, wherein a magnet provided on the side of the movable weight portion and a magnet provided on the side of the movable weight portion are disposed so as to face each other with different magnetic poles.