JPS6069340A - Oscillation damping device - Google Patents
Oscillation damping deviceInfo
- Publication number
- JPS6069340A JPS6069340A JP17669483A JP17669483A JPS6069340A JP S6069340 A JPS6069340 A JP S6069340A JP 17669483 A JP17669483 A JP 17669483A JP 17669483 A JP17669483 A JP 17669483A JP S6069340 A JPS6069340 A JP S6069340A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic fluid
- magnetic
- magnetic field
- vibration
- present
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
- F16F9/32—Details
- F16F9/53—Means for adjusting damping characteristics by varying fluid viscosity, e.g. electromagnetically
- F16F9/535—Magnetorheological [MR] fluid dampers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
- F16F15/03—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using magnetic or electromagnetic means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F6/00—Magnetic springs; Fluid magnetic springs, i.e. magnetic spring combined with a fluid
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Electromagnetism (AREA)
- Acoustics & Sound (AREA)
- Aviation & Aerospace Engineering (AREA)
- Vibration Prevention Devices (AREA)
- Fluid-Damping Devices (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、磁石体と磁性流体とを巧みに組合せてなるこ
とを特徴とする振動減衰装置に関するものであり、詳述
すれは、上記磁石体と磁性流体との組合せにおいて惹起
する当該磁性流体の磁場による見掛は粘度の増加現象を
利用した振動減衰装置に係るものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration damping device characterized by skillfully combining a magnet body and a magnetic fluid. The appearance caused by the magnetic field of the magnetic fluid is related to a vibration damping device that utilizes the phenomenon of increase in viscosity.
従来、振動減資装置としてバネ機構等をはじめとする各
棟のものが存在する。然しなから、従来の減衰装置lに
おいては、割振効果を一層錫めるという要求から、各釉
装置内の弾性機構部ン可及的に軟性としているため、制
振すべき振動が該弾性機構部自体にいつまでも長く持続
されてしまい、結果的に振動減衰の効率が低下してしま
うという欠陥がめった。また、従来の各種減辰装置にお
いては、振動発生源と装置内の割振機構部とが相互に接
触状態にあるのが一般であることから、当該接触状態を
原因として、適宜誘発した振動がこれを制振せんとする
機構部自体に伝ってしまい、それ自体が秦動媒介となっ
てしまうという不都合が正していた。Conventionally, there have been various types of vibration reduction devices including spring mechanisms and the like. However, in the conventional damping device, the elastic mechanism in each glazing device is made as soft as possible in order to improve the vibration distribution effect, so that the vibration to be damped is suppressed by the elastic mechanism. The problem is that the vibration damping efficiency of the vibration damping system decreases as a result. In addition, in various conventional depletion devices, the vibration generation source and the allocation mechanism inside the device are generally in contact with each other, so the vibrations induced as appropriate due to the contact state are caused by this. This corrected the problem that the vibration was transmitted to the mechanism itself that was intended to suppress the vibration, and the vibration itself became a medium of vibration.
而して、従来、前記欠陥等を解消しつつ振動減衰比を良
好にするという点が極めて* 要7a’課題とされてい
るのが実情であった。Therefore, in the past, the actual situation has been to improve the vibration damping ratio while eliminating the above-mentioned defects and the like.
本発明は、運上の如〈従来の状況に鑑みて開発されたも
のであり、その目的は、前記従来の欠陥、不都合を解r
gL、、誘発された各種の振動を即時的かつ萬効率に減
衰しつつ碌動減貨比の極めて良好な装置を提供すること
にある。The present invention was developed in view of the conventional situation, and its purpose is to overcome the defects and inconveniences of the conventional technology.
The object of the present invention is to provide a device that instantly and efficiently damps various induced vibrations and has an extremely good dynamic currency reduction ratio.
以下、添付した図面に沿って本発明の一実施例を説明す
る。An embodiment of the present invention will be described below with reference to the attached drawings.
本発明においては、その機構自体をこれに限建するもの
ではないが、図示で一例する如く、装置の機構を例えば
ピストン方式のものとした場合、非鉄材よりなる外筒部
1の内部に磁石体よりなる内筒部2を装置し、該内筒部
2の外周面と外局部1の内周面との間に適宜隙間の通路
部3を形成し、そして、当該外筒部1内に磁性流体4を
納入している。前記内筒部2は、その上面で非鉄材より
なる円筒部支持軸部5と固有し、該円筒部支持軸部5の
上方には適宜の平板部6を介して、例えば、本装置の用
途例として、後述の如く本装置nを防振架台に用いた場
合、適宜機器等の上架台Aが配置され、また、前記外筒
部1の下面には下架台Bが配置されることになる。In the present invention, the mechanism itself is not limited to this, but if the mechanism of the device is, for example, a piston type, as shown in the drawing, a magnet is placed inside the outer cylinder part 1 made of a non-ferrous material. An inner cylindrical portion 2 made of a body is provided, a passage portion 3 with an appropriate gap is formed between the outer circumferential surface of the inner cylindrical portion 2 and the inner circumferential surface of the outer portion 1, and a We are delivering magnetic fluid 4. The inner cylindrical part 2 has a cylindrical part support shaft part 5 made of a non-ferrous material on its upper surface, and an appropriate flat plate part 6 is provided above the cylindrical part support shaft part 5, for example, for the purpose of this apparatus. For example, when the present device n is used as a vibration-isolating pedestal as described later, an upper pedestal A for equipment etc. will be placed as appropriate, and a lower pedestal B will be placed on the lower surface of the outer cylinder section 1. .
前記内′@部2を構成する磁石体の構造は、図示する一
例の如く、複数の磁石体11ンアクリル製などの非磁性
材より7よるスペーサー12を介して積層し、該各磁石
体11はスペーサー12を間にして同極対向させて連固
設されている。而して、このようfi状態に形成した内
筒部2は、その外周側面において、次の様な状態の磁場
を惹起することにf;る。即ち、各磁石体11を同極対
向させて連設していることから、図中、破線の如く各磁
界13が生じ、介在した各スペーサー12の部分で最大
且つ強烈な磁場14(図中の黒点)が発生し、また磁場
は谷磁石体11の中心で最小なものとなる。この場合、
峙ζこ図示するものではないが、前記磁石体11を異極
対向すると、磁石体よりなる内筒部2の上・下側端部に
おいては極めて大きな磁場を得られるが、内筒部の外周
911面においては磁場が非常に小さいものとなってし
まうことになる。なお、本発明において、円筒部2を形
成する各磁石体11の配列組合せは、6柚のものが考え
られることは勿論であり、図示例に限建するものではな
い。As shown in the example shown in the figure, the structure of the magnets constituting the inner part 2 is such that a plurality of magnets 11 are made of a non-magnetic material such as acrylic and are laminated with a spacer 12 of 7 in between. are connected and fixed with the same polarity facing each other with a spacer 12 in between. The inner cylinder portion 2 thus formed in the fi state induces a magnetic field in the following state on its outer circumferential side surface. That is, since each magnet body 11 is arranged in series with the same polarity facing each other, each magnetic field 13 is generated as shown by the broken line in the figure, and the maximum and intense magnetic field 14 (in the figure) is generated at each intervening spacer 12. A sunspot) is generated, and the magnetic field is at its minimum at the center of the valley magnet body 11. in this case,
Although not shown in the drawings, if the magnets 11 have opposite polarities, an extremely large magnetic field can be obtained at the upper and lower ends of the inner cylinder 2 made of magnets, but the outer periphery of the inner cylinder In the 911 plane, the magnetic field becomes extremely small. In addition, in the present invention, the arrangement combination of the magnet bodies 11 forming the cylindrical portion 2 is of course possible, and is not limited to the illustrated example.
而して、本発明に係る装置においては、各磁石体11の
連設により磁場が極端な不均一に・よることを回避しつ
つ、外筒部1の内周面と円筒部2の外周面との間に形成
した狭い通路部3を流れる磁性流体4に極めて有効に磁
場14を加えることができ、更に、当該磁場14によっ
て、磁性流体4の見掛は粘度をより一層増大させること
ができる。そして、磁性流体4の該見掛は粘度は、磁性
流体4自体を濃縮又は希釈することにより、当該磁性流
体の粘度の濃度を変えることをちつて容易に調節するこ
とができる。In the device according to the present invention, the inner circumferential surface of the outer cylindrical portion 1 and the outer circumferential surface of the cylindrical portion 2 can be A magnetic field 14 can be applied very effectively to the magnetic fluid 4 flowing through the narrow passage 3 formed between the magnetic fluid 4 and the magnetic fluid 4, and the apparent viscosity of the magnetic fluid 4 can be further increased by the magnetic field 14. . The apparent viscosity of the magnetic fluid 4 can be easily adjusted by changing the viscosity concentration of the magnetic fluid 4 by concentrating or diluting the magnetic fluid 4 itself.
このように、例えは、ピストン方式より構成した本装置
は、内筒部2が上下速動するのlこ伴ない、磁性流体4
は狭い通路部3を速度勾配を生じつつ流れることになる
ため、円筒部2の上面と下面とに流れの平均速度に比例
した圧力差が生じることになり、これによって制動力が
発生し、更に該制動力を一層大きなものとなし、この制
動力を利用して誘発された自由振動を運かに減衰するこ
とを可能としたものである。そして、本発明は、磁性流
体4と各磁石体11とを前述例の如く組合せることによ
って、磁性流体4の粘性と通路部3の隙間とに依存して
いる制動力自体に、前記した強烈な磁場14により磁性
流体4の見掛は粘度の増大をもって更に一層大きな制動
効果を付加し、もって、誘発された振動を即時的且つ高
効率に減衰するようにしたものである。なお、当該制動
力は、前記付言した如く外筒部l内に納入した磁性流体
4の濃度を変えることにより、その調節が容易すJ、ま
た、更に一層太きな制動力を安する場合は、内筒部2を
形成する磁石体11の積層個数を増加するか或いは本装
置自体を並列に用いる寺の手段によって制動力の増大を
図ることができる〇
一方、本発明は、運上のように特に優れた減衰効果ヶ有
する他、磁性流体4の中に積層した磁石体11よりなる
内筒部2を配設したとともに円筒部2の外周側面に発生
する強烈な磁場14により、当該内筒部2は外筒部1の
内周面に全く接触することなく常にセンタリングされて
いるという特質を有するものである。従って、この装置
は、換言すれば無接触方式の減衰機構ということができ
、前記従来の如く、接触された各機構部自体が振動媒介
となってしまうという不都合を完全lこ解消するもので
ある。In this way, for example, in this device constructed using a piston system, as the inner cylinder portion 2 moves up and down rapidly, the magnetic fluid 4
flows through the narrow passage section 3 with a velocity gradient, creating a pressure difference between the upper and lower surfaces of the cylindrical section 2 that is proportional to the average velocity of the flow, which generates a braking force. The braking force is made even larger, and the induced free vibrations can be effectively damped using this braking force. By combining the magnetic fluid 4 and each magnet body 11 as described above, the present invention can reduce the braking force itself, which is dependent on the viscosity of the magnetic fluid 4 and the gap between the passage portions 3, to the above-mentioned intense force. The magnetic field 14 increases the apparent viscosity of the magnetic fluid 4, thereby adding an even greater damping effect, thereby damping the induced vibrations instantly and with high efficiency. As mentioned above, the braking force can be easily adjusted by changing the concentration of the magnetic fluid 4 delivered into the outer cylindrical part l. The braking force can be increased by increasing the number of laminated magnet bodies 11 forming the inner cylindrical portion 2 or by using the present device itself in parallel. In addition to having a particularly excellent damping effect, the inner cylindrical part 2 made of laminated magnets 11 is disposed in the magnetic fluid 4, and the intense magnetic field 14 generated on the outer circumferential side of the cylindrical part 2 makes it possible to The cylindrical portion 2 has the characteristic that it is always centered without contacting the inner circumferential surface of the outer cylindrical portion 1 at all. Therefore, in other words, this device can be called a non-contact type damping mechanism, which completely eliminates the disadvantage that the contacting mechanical parts themselves become vibration media as in the conventional method. .
ここに、本装置の機構例及び用途例として図示した一実
施例は、ピストン方式より本発明を構成し、その用途を
適亘機器等の防振架台とする場合であり、図中、上架台
Aはバネ部Cによって下架台B上に支持されているもの
であり、本装置を当該上働下架台の間に設置したもので
ある。従って、予め、該防振架台の固有周期より減衰延
数をめ、更には磁性流体4を適度7.1′濃度とする等
により、本発明に係る減衰装置をこのような防振架台に
用いた場合、装置自体、如何なる振動媒介となること7
.、<、上・下架台A・Bのいずれかに誘発された自由
振動を素早く減衰させることができることになる。One embodiment shown here as an example of the mechanism and application of the present device is a case in which the present invention is constructed using a piston method and is used as a vibration-isolating pedestal for suitable equipment, etc. In the figure, the upper pedestal is A is supported on a lower mount B by a spring portion C, and this device is installed between the upper and lower mounts. Therefore, the damping device according to the present invention can be used in such a vibration-isolating frame by determining the damping extension in advance from the natural period of the vibration-isolating frame, and further setting the magnetic fluid 4 to an appropriate concentration of 7.1'. If so, the device itself may become a medium of vibration7.
.. , <, This means that free vibrations induced in either the upper or lower mounts A or B can be quickly damped.
なお、本装置は、上記−用途例に限ることなく各種分野
の振動減衰として使用できることは勿論である。It goes without saying that this device can be used as vibration damping in various fields without being limited to the above-mentioned application example.
以上説明したように、磁石体と磁性流体とを巧みに組合
せてなることを特徴とした本発明は、前記従来の味題を
兄事に解決しつつ従来の欠陥、不仲合乞解消できること
の他、機構部が無接触であることから各部の摩耗が全く
ないので極めてその耐用が長期となり、また本発明にお
いては、円筒部のセンタリングのための特別手段は全く
不要−ので軸受部等は全く必要の1.、いものと7.す
、更に、外筒部内に磁性流体を納入してI、16本発明
は外筒部上面のシーリング等が全く不要となるなど、優
れた諸効果を併有しつつランダムな各種の誘発振動に対
して広汎に適用できるという極めて曖れた振動減衰装置
である。As explained above, the present invention, which is characterized by a skillful combination of a magnetic body and a magnetic fluid, solves the problems of the conventional art while solving the defects and disagreements of the conventional art. Since the mechanical parts are non-contact, there is no wear on each part, so the service life is extremely long.In addition, in the present invention, there is no need for any special means for centering the cylindrical part, so no bearings or the like are necessary. 1. , and 7. Furthermore, by delivering the magnetic fluid inside the outer cylinder, the present invention has excellent effects such as no sealing on the upper surface of the outer cylinder, and is effective against various kinds of random induced vibrations. It is an extremely vague vibration damping device that can be applied to a wide range of situations.
第1図は本発明をピストン方式の機構より構成した一実
施例で且つ本発明の一用途例の縦断側面図、第2図は第
1図における磁石体の正面図、第3図(イ)は本発明を
防振架台に使用した一例を示す概略側面説明図、第3図
(ロ)は同概略平面説明図である。
1・・・外筒部、2・・・内筒部、3・・・通路部、4
・・・磁性流体、5・・・円筒部支持軸部、6・・・平
板部、11・・・磁石体、12・・・スペーサー、13
II・・磁界、14・・・磁場。
手 糸売 ネ山 jE a外 (、Xj:y 式 )昭
和59年 2月28日
昭和58年特、i″F願第 176694号2 発明の
名称
振動i威衰装置t
3、補正をする堪
市外との関係 特許出願人
住所 東京部品用区東五反Iヨ5−1o−18(岩田ビ
ル)氏名 ヤクモ工業株式会社
4、代理人
住所 東京都爪区赤坂9丁目1番7号
5 補m命令の日刊
昭和59年 1月31日(発送日)
7、補正の内容
タイプ印書した願書および明細書を提出いたします8、
添イづ書類の目録Fig. 1 is a longitudinal cross-sectional side view of an embodiment of the present invention constructed from a piston-type mechanism and an example of the application of the present invention, Fig. 2 is a front view of the magnet body in Fig. 1, and Fig. 3 (A). 3 is a schematic side view showing an example of the use of the present invention in a vibration-isolating frame, and FIG. 3(B) is a schematic plan view of the same. 1... Outer cylinder part, 2... Inner cylinder part, 3... Passage part, 4
... Magnetic fluid, 5... Cylindrical part support shaft part, 6... Flat plate part, 11... Magnet body, 12... Spacer, 13
II...Magnetic field, 14...Magnetic field. Te Itouri Neyama jE a outside (,Xj:y formula) February 28, 1980 Special Patent Application No. 176694 2 Name of the invention Vibration i Dampening device t 3. Relationship with outside the city Patent applicant address 5-1o-18 Higashigotan Iyo, Parts Ward, Tokyo (Iwata Building) Name Yakumo Kogyo Co., Ltd. 4, agent address 9-1-7-5 Akasaka, Tsume-ku, Tokyo Supplementary address m-order daily January 31, 1982 (shipping date) 7. We will submit the application and specification with the content type of the amendment printed 8.
List of attached documents
Claims (1)
性流体の見掛は粘度を一層増大させることにより大きな
制動力を惹起し、該大きな制動力をもって、誘発された
各種の自由撮動を速やかに減衰させるとともに過渡特性
および位相特性を極めて良好に改善するようにした磁石
体と磁性流体との巧みな組合せよりなることを特徴とす
る振動減衰装置。A strong magnetic field is generated by the arrangement of an outstanding number of magnets, and the apparent viscosity of the magnetic fluid is further increased, thereby inducing a large braking force, and with this large braking force, various types of induced free shooting are possible. A vibration damping device characterized in that it consists of an ingenious combination of a magnetic body and a magnetic fluid, which provides rapid damping and extremely improved transient and phase characteristics.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58176694A JPH081233B2 (en) | 1983-09-24 | 1983-09-24 | Vibration damping device |
US06/652,633 US4679775A (en) | 1983-09-24 | 1984-09-20 | Vibration damping equipment |
DE19843434897 DE3434897A1 (en) | 1983-09-24 | 1984-09-22 | VIBRATION DAMPING DEVICE |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58176694A JPH081233B2 (en) | 1983-09-24 | 1983-09-24 | Vibration damping device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6069340A true JPS6069340A (en) | 1985-04-20 |
JPH081233B2 JPH081233B2 (en) | 1996-01-10 |
Family
ID=16018100
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP58176694A Expired - Lifetime JPH081233B2 (en) | 1983-09-24 | 1983-09-24 | Vibration damping device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH081233B2 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60180838U (en) * | 1984-05-12 | 1985-11-30 | 株式会社トーキン | magnetic fluid damper |
JPS60180841U (en) * | 1984-05-12 | 1985-11-30 | 株式会社トーキン | magnetic fluid damper |
JPH034048A (en) * | 1989-06-01 | 1991-01-10 | Bridgestone Corp | Vibro-isolating supporting device |
CN103573896A (en) * | 2013-11-08 | 2014-02-12 | 苏州康开电气有限公司 | Magnetizing and damping device |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5769136A (en) * | 1980-10-13 | 1982-04-27 | Yakumo Kogyo Kk | Vibration insulator |
-
1983
- 1983-09-24 JP JP58176694A patent/JPH081233B2/en not_active Expired - Lifetime
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5769136A (en) * | 1980-10-13 | 1982-04-27 | Yakumo Kogyo Kk | Vibration insulator |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60180838U (en) * | 1984-05-12 | 1985-11-30 | 株式会社トーキン | magnetic fluid damper |
JPS60180841U (en) * | 1984-05-12 | 1985-11-30 | 株式会社トーキン | magnetic fluid damper |
JPH034048A (en) * | 1989-06-01 | 1991-01-10 | Bridgestone Corp | Vibro-isolating supporting device |
CN103573896A (en) * | 2013-11-08 | 2014-02-12 | 苏州康开电气有限公司 | Magnetizing and damping device |
Also Published As
Publication number | Publication date |
---|---|
JPH081233B2 (en) | 1996-01-10 |
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