JP2572511Y2 - Eddy current type reduction gear - Google Patents
Eddy current type reduction gearInfo
- Publication number
- JP2572511Y2 JP2572511Y2 JP1992057701U JP5770192U JP2572511Y2 JP 2572511 Y2 JP2572511 Y2 JP 2572511Y2 JP 1992057701 U JP1992057701 U JP 1992057701U JP 5770192 U JP5770192 U JP 5770192U JP 2572511 Y2 JP2572511 Y2 JP 2572511Y2
- Authority
- JP
- Japan
- Prior art keywords
- magnet support
- magnet
- support cylinder
- braking
- eddy current
- 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.)
- Expired - Fee Related
Links
Landscapes
- Dynamo-Electric Clutches, Dynamo-Electric Brakes (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本考案は主として大型車両の摩擦
ブレーキを補助する渦電流式減速装置、特に制動時磁石
支持筒に周方向等間隔に並設した多数の永久磁石（以下
単に磁石という）を、回転する制動ドラムの内周面に接
近させて、渦電流に基づく制動トルクを制動ドラムに与
える渦電流式減速装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to an eddy current type speed reducer for assisting a friction brake of a large vehicle. To an eddy current type speed reducer which brings a braking torque based on an eddy current to the brake drum by bringing the brake drum closer to the inner peripheral surface of the rotating brake drum.
【０００２】[0002]
【従来の技術】回転する制動ドラムの内周面に周方向等
間隔に並ぶ多数の永久磁石を接近させて、制動ドラムに
制動トルクを与える渦電流式減速装置には、特開平3-86
060 号公報に開示されるように、磁石支持筒を固定筒の
内部で軸方向に移動して、制動時磁石支持筒の各磁石を
固定筒の強磁性板（ポールピース）に全面的に対向させ
る一方、非制動時各磁石を強磁性板から引退させる形式
のものと、特願平2-112026号に開示されるように、磁石
支持筒を固定筒の内部で回動して、制動時磁石支持筒の
各磁石を固定筒の強磁性板に全面的に対向させる一方、
非制動時相隣接する磁石を共通の強磁性板に部分的に対
向させる形式のものとがある。2. Description of the Related Art An eddy current type speed reducer for applying a braking torque to a braking drum by bringing a number of permanent magnets arranged at equal intervals in a circumferential direction close to the inner peripheral surface of a rotating braking drum is disclosed in Japanese Patent Application Laid-Open No. 3-86.
As disclosed in Japanese Patent Publication No. 060, the magnet support cylinder is moved in the axial direction inside the fixed cylinder so that each magnet of the magnet support cylinder is completely opposed to the ferromagnetic plate (pole piece) of the fixed cylinder during braking. On the other hand, in the non-braking mode, each magnet is retired from the ferromagnetic plate, and as disclosed in Japanese Patent Application No. 2-112026, the magnet support cylinder is rotated inside the fixed cylinder, and While each magnet of the magnet support cylinder is entirely opposed to the ferromagnetic plate of the fixed cylinder,
There is a type in which adjacent magnets in the non-braking phase are partially opposed to a common ferromagnetic plate.
【０００３】何れにしても、磁性体からなる磁石支持筒
はヨークとして、磁石を挟む制動ドラムと磁石支持筒と
の間に磁気回路を形成するものであるから、相当の肉厚
が要求される。しかし、肉厚の磁石支持筒は磁石支持筒
のみならず、強度上から磁石支持筒を案内支持する固定
筒にも重量増加をもたらす。In any case, since the magnet support cylinder made of a magnetic material is a yoke that forms a magnetic circuit between the brake drum holding the magnet and the magnet support cylinder, a considerable thickness is required. . However, the thick magnet support cylinder not only increases the weight of the magnet support cylinder, but also increases the weight of the fixed cylinder that guides and supports the magnet support cylinder due to its strength.
【０００４】[0004]
【考案が解決しようとする課題】本考案の目的は上述の
問題に鑑み、磁気回路に影響を与えないで、装置の軽量
化を実現する渦電流式減速装置を提供することにある。SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide an eddy current type speed reducer which does not affect a magnetic circuit and realizes a lighter device.
【０００５】[0005]
【課題を解決するための手段】上記目的を達成するため
に、本考案の構成は制動ドラムの内部に断面長方形の内
空部を有する固定筒を配設し、固定筒の外周壁に周方向
等間隔に多数の強磁性板を配設し、固定筒の内空部に支
持した磁性体からなる磁石支持筒の外周面に、各強磁性
板に一方の磁極が対向しかつ極性が周方向に交互に異な
る永久磁石を結合し、各永久磁石が強磁性板に全面的に
対向する制動位置と対向しない非制動位置とへ磁石支持
筒を駆動する手段を備え、磁石支持筒の内周壁の各磁石
の周方向中心に対応する部分の肉厚を他の部分よりも薄
くしたものである。In order to achieve the above-mentioned object, according to the present invention, a fixed cylinder having an inner space with a rectangular cross section is disposed inside a braking drum, and a circumferential direction is provided on an outer peripheral wall of the fixed cylinder. A large number of ferromagnetic plates are arranged at equal intervals, and one magnetic pole faces each ferromagnetic plate on the outer peripheral surface of a magnet support cylinder made of a magnetic material supported in the inner space of the fixed cylinder, and the polarity is circumferential. And a means for driving the magnet support cylinder to a braking position in which each permanent magnet entirely faces the ferromagnetic plate and a non-braking position in which each permanent magnet does not face the ferromagnetic plate. The thickness of the portion corresponding to the circumferential center of each magnet is made thinner than the other portions.
【０００６】[0006]
【作用】磁石を挟んで制動ドラムと磁石支持筒との間に
形成される磁気回路に着目すると、磁石支持筒の内周壁
部には磁気回路に殆ど関与しない無駄な肉部が存在す
る。本考案は磁石支持筒の内周壁に軸方向の溝を設け
て、磁石支持筒の各磁石の周方向中心に対応する部分の
肉厚を薄くすることにより、磁石支持筒の重量を低減す
るものである。When focusing on the magnetic circuit formed between the braking drum and the magnet support cylinder with the magnet interposed therebetween, there is a useless flesh that hardly participates in the magnetic circuit on the inner peripheral wall of the magnet support cylinder. The present invention reduces the weight of the magnet support cylinder by providing an axial groove in the inner peripheral wall of the magnet support cylinder and reducing the thickness of the portion corresponding to the circumferential center of each magnet of the magnet support cylinder. It is.
【０００７】磁石支持筒を鋳造する場合は、磁石支持筒
の内周壁に偏倚して、各磁石の周方向中心に対応する部
分に、軸方向の穴を設けても軽量化でき、磁石支持筒の
内側に円筒面が残るので、磁石支持筒を回動して制動と
非制動の切換えを行う形式の渦電流式減速装置に有利で
ある。In the case of casting the magnet support cylinder, the weight can be reduced even if an axial hole is provided at a portion corresponding to the circumferential center of each magnet so as to be biased toward the inner peripheral wall of the magnet support cylinder. Since a cylindrical surface remains inside the eddy current reduction device of the type in which the magnet support cylinder is rotated to switch between braking and non-braking.
【０００８】[0008]
【実施例】図１は本考案に係る磁石支持筒を固定筒の内
部で回動して、制動と非制動に切り換える形式の渦電流
式減速装置の側面断面図、図２は同正面断面図である。
本考案による渦電流式減速装置は、例えば車両用変速機
の出力回転軸１に結合される導体からなる制動ドラム７
と、制動ドラム７の内部に配設される非磁性体からなる
不動の案内筒１０と、案内筒１０の断面長方形の内空部
に回動可能に支持した磁石支持筒１４とを備えている。
制動ドラム７はボス５のフランジ部５ａを、駐車ブレー
キの制動ドラム３の端壁部と一緒に、回転軸１にスプラ
イン嵌合固定した取付フランジ２に重ね合され、かつ複
数のボルト４とナツトにより締結される。ボス５から放
射状に延びる多数のスポーク６に、冷却フイン８を備え
た制動ドラム７の一端が結合される。1 is a side sectional view of an eddy current type speed reducer of the type in which a magnet supporting tube according to the present invention is rotated inside a fixed tube to switch between braking and non-braking, and FIG. 2 is a front sectional view of the same. It is.
The eddy current type speed reducer according to the present invention includes a braking drum 7 made of a conductor coupled to an output rotary shaft 1 of a vehicle transmission, for example.
A stationary guide tube 10 made of a non-magnetic material disposed inside the braking drum 7, and a magnet support tube 14 rotatably supported in an inner space of the guide tube 10 having a rectangular cross section. .
The brake drum 7 overlaps the flange portion 5a of the boss 5 together with the end wall portion of the brake drum 3 of the parking brake on the mounting flange 2 which is spline-fitted and fixed to the rotating shaft 1, and includes a plurality of bolts 4 and nuts. Is concluded. One end of a brake drum 7 having a cooling fin 8 is connected to a number of spokes 6 extending radially from the boss 5.
【０００９】断面箱形の固定筒１０は例えば断面Ｃ形を
なす筒体に、環状の蓋板１１を結合して構成される。固
定筒１０は適当な手段により例えば変速機の歯車箱に固
定される。固定筒１０の外周壁１０ａに多数の強磁性板
１５が周方向等間隔に結合される。好ましくは、強磁性
板１５は固定筒１０の成形時鋳ぐるまれる。強磁性板１
５は長方形の板状のものであつて、板面は円弧状に湾曲
される。強磁性板１５の周壁は突条２５を一体に形成さ
れ、固定筒１０の外周壁１０ａと強磁性板１５との鋳造
による結合度を高める。磁石支持筒１４は固定筒１０の
内空部、詳しくは内周壁１０ｂに軸受１２により回動可
能に支持される。The fixed cylinder 10 having a box-shaped cross section is constituted by connecting an annular lid plate 11 to a cylinder having a C-shaped cross section, for example. The fixed cylinder 10 is fixed by a suitable means, for example, to a gearbox of a transmission. Many ferromagnetic plates 15 are joined to the outer peripheral wall 10a of the fixed cylinder 10 at equal intervals in the circumferential direction. Preferably, the ferromagnetic plate 15 is cast when the fixed cylinder 10 is formed. Ferromagnetic plate 1
Reference numeral 5 denotes a rectangular plate, and the plate surface is curved in an arc shape. The peripheral wall of the ferromagnetic plate 15 is formed integrally with the ridge 25 to enhance the coupling between the outer peripheral wall 10a of the fixed cylinder 10 and the ferromagnetic plate 15 by casting. The magnet support cylinder 14 is rotatably supported by the bearing 12 on the inner space of the fixed cylinder 10, specifically, on the inner peripheral wall 10 b.
【００１０】固定筒１０の左端壁に、好ましくは３つの
流体圧アクチユエータ２０が周方向等間隔に結合され
る。流体圧アクチユエータ２０はシリンダ１８にピスト
ン１７を嵌装してなり、ピストン１７から外部へ突出す
るロツドは、磁石支持筒１４から固定筒１０の左端壁の
円弧状のスリツト１８ａを経て突出する腕１６に連結さ
れる。Preferably, three fluid pressure actuators 20 are connected to the left end wall of the fixed cylinder 10 at equal circumferential intervals. The fluid pressure actuator 20 has a piston 17 fitted in a cylinder 18, and a rod projecting outward from the piston 17 has an arm 16 projecting from the magnet support cylinder 14 through an arc-shaped slit 18a on the left end wall of the fixed cylinder 10. Linked to
【００１１】図２に示すように、磁石支持筒１４は各強
磁性板１５に１つずつ対応する磁石２４を結合される。
磁石支持筒１４は磁性体からなり、各強磁性板１５に対
向する磁石２４は、極性が周方向に交互に異なるように
配設される。As shown in FIG. 2, the magnet support cylinder 14 has a magnet 24 corresponding to each ferromagnetic plate 15.
The magnet support tube 14 is made of a magnetic material, and the magnets 24 facing the ferromagnetic plates 15 are arranged so that the polarities are alternately different in the circumferential direction.
【００１２】本考案によれば、磁石支持筒１４の内周壁
の、各磁石２４の周方向中心に対応する部分に、軸方向
に延びるＶ形の溝２２が設けられる。つまり、本考案は
磁石支持筒１４の内周壁の、各磁石２４の周方向中心に
対応する部分に薄肉部を形成し、磁石支持筒１４の重量
を軽減するものである。図示の磁石支持筒１４の回動に
より制動と非制動の切換えを行う形式の渦電流式減速装
置では、磁石支持筒１４の内側の円筒面が溝２２により
切り欠かれるが、磁石支持筒１４は磁石２４の半配列ピ
ツチ分だけ正逆回動するものであるから、軸受１２の外
輪と溝２２との間に空部が生じても、特に問題はない。According to the present invention, a V-shaped groove 22 extending in the axial direction is provided in a portion of the inner peripheral wall of the magnet support tube 14 corresponding to the circumferential center of each magnet 24. That is, in the present invention, a thin portion is formed on the inner peripheral wall of the magnet support tube 14 at a portion corresponding to the circumferential center of each magnet 24 to reduce the weight of the magnet support tube 14. In the eddy current type speed reducer of the type in which switching between braking and non-braking is performed by turning the illustrated magnet support cylinder 14, the cylindrical surface inside the magnet support cylinder 14 is cut out by the groove 22. Since it rotates forward and backward by the pitch of the half array of the magnets 24, there is no problem even if an empty space is formed between the outer ring of the bearing 12 and the groove 22.
【００１３】図４に示すように、磁石支持筒１４を鋳造
する場合は、磁石支持筒１４の内周壁に接近して、各磁
石２４の周方向中心に対応する部分に、軸方向の穴２３
を設けても軽量化でき、磁石支持筒２４の内側に円筒面
が残るので、磁石支持筒１４の軸受部に特段の配慮を要
しない。As shown in FIG. 4, when casting the magnet support tube 14, the inner peripheral wall of the magnet support tube 14 is approached, and a portion corresponding to the circumferential center of each magnet 24 is provided with an axial hole 23.
Is provided, the weight can be reduced, and a cylindrical surface remains inside the magnet support cylinder 24, so that special consideration is not required for the bearing portion of the magnet support cylinder 14.
【００１４】次に、本考案による渦電流式減速装置の作
動について説明する。制動時、図２に示すように、各磁
石２４は各強磁性板１５に全面的に対向し、磁石支持筒
１４と制動ドラム７との間に磁気回路２６を形成する。
回転する制動ドラム７が磁界を横切る時、制動ドラム７
に渦電流が流れ、制動ドラム７は制動トルクを受ける。
溝２２の周方向位置は各磁石の周方向中心にあつて、磁
石支持筒１４の内周壁にあるから、磁気回路２６の磁気
抵抗が増加し、磁気回路２６の磁束数が減じられるなど
の悪影響はなく、したがつて、制動能力が低下すること
もない。Next, the operation of the eddy current speed reducer according to the present invention will be described. At the time of braking, as shown in FIG. 2, each magnet 24 entirely opposes each ferromagnetic plate 15, and forms a magnetic circuit 26 between the magnet support tube 14 and the braking drum 7.
When the rotating brake drum 7 crosses the magnetic field, the brake drum 7
An eddy current flows through the brake drum 7, and the braking drum 7 receives a braking torque.
Since the circumferential position of the groove 22 is located at the circumferential center of each magnet and on the inner circumferential wall of the magnet support tube 14, the magnetic resistance of the magnetic circuit 26 increases, and the number of magnetic fluxes in the magnetic circuit 26 decreases, which has an adverse effect. Therefore, the braking ability does not decrease.
【００１５】非制動時、流体圧アクチユエータ２０によ
り磁石支持筒１４を強磁性板１５の半配列ピツチ分だけ
回動すると、図３に示すように、極性が異なる２つの磁
石２４が部分的に各強磁性板１５に対向する。各強磁性
板１５と磁石支持筒１４との間に、短絡的磁気回路２７
が生じ、磁石２４は磁界を制動ドラム７に及ぼさない。When the magnet support cylinder 14 is rotated by a half-pitch of the ferromagnetic plate 15 by the fluid pressure actuator 20 at the time of non-braking, as shown in FIG. It faces the ferromagnetic plate 15. A short-circuit magnetic circuit 27 is provided between each ferromagnetic plate 15 and the magnet support cylinder 14.
And the magnet 24 does not exert a magnetic field on the braking drum 7.
【００１６】なお、本考案は上述の形式の渦電流式減速
装置に限定されるものではなく、特願平2-112026号や特
開平3-86060 号公報に開示される形式の渦電流式減速装
置にも適用できる。Incidentally, the present invention is not limited to the eddy current type speed reducer of the above-mentioned type, but is disclosed in Japanese Patent Application No. 2-112026 and Japanese Patent Application Laid-Open No. 3-86060. Applicable to devices.
【００１７】[0017]
【考案の効果】本考案は上述のように、制動ドラムの内
部に断面長方形の内空部を有する固定筒を配設し、固定
筒の外周壁に周方向等間隔に多数の強磁性板を配設し、
固定筒の内空部に支持した磁性体からなる磁石支持筒の
外周面に、各強磁性板に一方の磁極が対向しかつ極性が
周方向に交互に異なる永久磁石を結合し、各永久磁石が
強磁性板に全面的に対向する制動位置と対向しない非制
動位置とへ磁石支持筒を駆動する手段を備え、磁石支持
筒の内周壁の各磁石の周方向中心に対応する部分の肉厚
を他の部分よりも薄くしたから、磁石支持筒を軽量化で
きるだけでなく、磁石支持筒を案内支持する固定筒の強
度負担が軽くなり、装置全体の重量を削減できる。As described above, according to the present invention, a fixed cylinder having an inner space with a rectangular cross section is disposed inside the braking drum, and a large number of ferromagnetic plates are provided on the outer peripheral wall of the fixed cylinder at equal circumferential intervals. Arrange,
On the outer peripheral surface of a magnet support cylinder made of a magnetic material supported in the inner space of the fixed cylinder, a permanent magnet whose one magnetic pole faces each ferromagnetic plate and whose polarity is alternately changed in the circumferential direction is joined to each permanent magnet. Is provided with a means for driving the magnet support cylinder to a braking position that entirely faces the ferromagnetic plate and a non-braking position that does not face the ferromagnetic plate. Is thinner than the other parts, not only can the magnet support cylinder be reduced in weight, but also the strength load on the fixed cylinder that guides and supports the magnet support cylinder can be reduced, and the weight of the entire apparatus can be reduced.
【００１８】薄肉部の周方向位置は各磁石の周方向中心
にあつて、磁石支持筒の内周壁にあるから、磁気回路の
磁気抵抗が増加し、磁気回路の磁束数が減じられるなど
の悪影響はなく、したがつて、制動能力が低下すること
もない。Since the circumferential portion of the thin portion is located at the circumferential center of each magnet and located on the inner circumferential wall of the magnet support cylinder, adverse effects such as an increase in the magnetic resistance of the magnetic circuit and a decrease in the number of magnetic fluxes in the magnetic circuit. Therefore, the braking ability does not decrease.
【図１】本考案に係る渦電流式減速装置の上半部を示す
側面断面図である。FIG. 1 is a side sectional view showing an upper half portion of an eddy current type reduction gear according to the present invention.
【図２】図１の線２Ａ−２Ａによる減速装置の制動時を
示す正面断面図である。FIG. 2 is a front sectional view showing a state where the speed reduction device is braked along a line 2A-2A in FIG. 1;
【図３】同減速装置の非制動時を示す正面断面図であ
る。FIG. 3 is a front cross-sectional view showing the non-braking state of the reduction gear transmission.
【図４】本考案の変更実施例に係る減速装置の正面断面
図である。FIG. 4 is a front sectional view of a reduction gear transmission according to a modified embodiment of the present invention.
１：回転軸 ７：制動ドラム １０：固定筒 １０ａ：
外周壁 １４：磁石支持筒 １５：強磁性板 １５ｂ：
後端部 ２４：磁石1: rotating shaft 7: braking drum 10: fixed cylinder 10a:
Outer peripheral wall 14: Magnet support cylinder 15: Ferromagnetic plate 15b:
Rear end 24: magnet
Claims (1)
有する固定筒を配設し、固定筒の外周壁に周方向等間隔
に多数の強磁性板を配設し、固定筒の内空部に支持した
磁性体からなる磁石支持筒の外周面に、各強磁性板に一
方の磁極が対向しかつ極性が周方向に交互に異なる永久
磁石を結合し、各永久磁石が強磁性板に全面的に対向す
る制動位置と対向しない非制動位置とへ磁石支持筒を駆
動する手段を備え、磁石支持筒の内周壁の各磁石の周方
向中心に対応する部分の肉厚を他の部分よりも薄くした
ことを特徴とする渦電流式減速装置。1. A fixed cylinder having an inner space with a rectangular cross section is disposed inside a braking drum, and a large number of ferromagnetic plates are disposed at equal circumferential intervals on an outer peripheral wall of the fixed cylinder. On the outer peripheral surface of a magnet support cylinder made of a magnetic material supported in the empty space, one ferromagnetic plate is opposed to each ferromagnetic plate, and permanent magnets whose polarity alternates in the circumferential direction are alternately connected. Means for driving the magnet support cylinder to a braking position that entirely opposes and a non-braking position that does not oppose, and the thickness of a portion corresponding to the circumferential center of each magnet on the inner peripheral wall of the magnet support cylinder is set to another portion. An eddy current type reduction gear characterized by being thinner than that.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1992057701U JP2572511Y2 (en) | 1992-07-24 | 1992-07-24 | Eddy current type reduction gear |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1992057701U JP2572511Y2 (en) | 1992-07-24 | 1992-07-24 | Eddy current type reduction gear |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0617386U JPH0617386U (en) | 1994-03-04 |
| JP2572511Y2 true JP2572511Y2 (en) | 1998-05-25 |
Family
ID=13063246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1992057701U Expired - Fee Related JP2572511Y2 (en) | 1992-07-24 | 1992-07-24 | Eddy current type reduction gear |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2572511Y2 (en) |
-
1992
- 1992-07-24 JP JP1992057701U patent/JP2572511Y2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0617386U (en) | 1994-03-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |