JP6870397B2

JP6870397B2 - Eddy current speed reducer and its manufacturing method

Info

Publication number: JP6870397B2
Application number: JP2017048285A
Authority: JP
Inventors: 野口　泰隆; 泰隆野口; 山口　博行; 博行山口; 方宏田坂; 今西　憲治; 憲治今西; 裕野上; 大輔佐谷
Original assignee: Nippon Steel Corp
Current assignee: Nippon Steel Corp
Priority date: 2017-03-14
Filing date: 2017-03-14
Publication date: 2021-05-12
Anticipated expiration: 2037-03-14
Also published as: JP2018153017A

Description

本発明は、永久磁石を用いた渦電流式減速装置およびその製造方法に関する。 The present invention relates to an eddy current speed reducer using a permanent magnet and a method for manufacturing the same.

従来、トラックおよびバス等の大型自動車において、補助ブレーキとして、渦電流式減速装置が用いられている。図７は、従来の渦電流式減速装置の一例を示す概略断面図である。 Conventionally, in large automobiles such as trucks and buses, an eddy current type speed reducer has been used as an auxiliary brake. FIG. 7 is a schematic cross-sectional view showing an example of a conventional eddy current type speed reducer.

図７に示す渦電流式減速装置１００は、ロータ１０およびステータ１２を備えている。ロータ１０は、連結部材１０ａ、連結部材１０ｂ、および制動ドラム１０ｃを備えている。連結部材１０ａは、筒形状を有し、プロペラシャフト等の回転軸５０に固定される。連結部材１０ｂは、例えば中空円板形状を有し、連結部材１０ａに固定される。制動ドラム１０ｃは、円筒形状を有し、連結部材１０ｂの外周縁に固定されている。制動ドラム１０ｃは、強磁性体材料からなる。このような構成により、連結部材１０ａ、連結部材１０ｂおよび制動ドラム１０ｃは、回転軸５０と一体的に回転する。なお、図示は省略しているが、制動ドラム１０ｃの外周面には、例えば、複数のフィンが設けられる。 The eddy current speed reducer 100 shown in FIG. 7 includes a rotor 10 and a stator 12. The rotor 10 includes a connecting member 10a, a connecting member 10b, and a braking drum 10c. The connecting member 10a has a tubular shape and is fixed to a rotating shaft 50 such as a propeller shaft. The connecting member 10b has, for example, a hollow disk shape and is fixed to the connecting member 10a. The braking drum 10c has a cylindrical shape and is fixed to the outer peripheral edge of the connecting member 10b. The braking drum 10c is made of a ferromagnetic material. With such a configuration, the connecting member 10a, the connecting member 10b, and the braking drum 10c rotate integrally with the rotating shaft 50. Although not shown, a plurality of fins are provided on the outer peripheral surface of the braking drum 10c, for example.

ステータ１２は、ステータ本体１２ａ、回動ユニット１２ｂ、および固定ユニット１２ｃを備えている。ステータ本体１２ａは、連結部材１０ａに対して相対回転可能に設けられている。したがって、ステータ本体１２ａ（ステータ１２）は、回転軸５０及びロータ１０が回転しても回転しない。ステータ本体１２ａは、例えば、車体（図示せず）に固定される。 The stator 12 includes a stator body 12a, a rotating unit 12b, and a fixing unit 12c. The stator body 12a is provided so as to be rotatable relative to the connecting member 10a. Therefore, the stator body 12a (stator 12) does not rotate even if the rotating shaft 50 and the rotor 10 rotate. The stator body 12a is fixed to, for example, a vehicle body (not shown).

回動ユニット１２ｂは、第１支持体１４および複数の永久磁石１６を含む。第１支持体１４は、強磁性体材料（例えば、炭素鋼）からなる。固定ユニット１２ｃは、第２支持体１８および複数のポールピース２０を含む。第２支持体１８は、非磁性体材料からなる。ポールピース２０は、強磁性体材料からなる。 The rotating unit 12b includes a first support 14 and a plurality of permanent magnets 16. The first support 14 is made of a ferromagnetic material (for example, carbon steel). The fixing unit 12c includes a second support 18 and a plurality of pole pieces 20. The second support 18 is made of a non-magnetic material. The pole piece 20 is made of a ferromagnetic material.

図８は、制動ドラム１０ｃ、回動ユニット１２ｂおよび固定ユニット１２ｃの断面の一部を示す概略図であり、図８（ａ）は、制動時の状態を示し、図８（ｂ）は、非制動時の状態を示す。なお、図８に示した断面は、制動ドラム１０ｃの軸方向Ａ（図７参照）に垂直な断面である。 FIG. 8 is a schematic view showing a part of a cross section of the braking drum 10c, the rotating unit 12b, and the fixed unit 12c. FIG. 8A shows a state at the time of braking, and FIG. 8B shows a non-braking state. Indicates the state during braking. The cross section shown in FIG. 8 is a cross section perpendicular to the axial direction A (see FIG. 7) of the braking drum 10c.

図７および図８を参照して、第１支持体１４は円筒形状を有し、ステータ本体１２ａに対して相対回転可能にステータ本体１２ａに支持されている。第１支持体１４は、制動ドラム１０ｃの径方向において、制動ドラム１０ｃの内側に配置されている。第１支持体１４は、図示しない駆動装置によって駆動されることによって、周方向に回動する。 With reference to FIGS. 7 and 8, the first support 14 has a cylindrical shape and is supported by the stator body 12a so as to be rotatable relative to the stator body 12a. The first support 14 is arranged inside the braking drum 10c in the radial direction of the braking drum 10c. The first support 14 rotates in the circumferential direction by being driven by a drive device (not shown).

図８を参照して、複数の永久磁石１６は、第１支持体１４の周方向に沿って並ぶように、第１支持体１４の外周面に固定されている。永久磁石１６は、例えば、接着材によって第１支持体１４に固定されている。複数の永久磁石１６は、第１支持体１４の周方向において、等間隔に配置されている。各永久磁石１６は、第１支持体１４の径方向における一方側にＮ極を有し、前記径方向における他方側にＳ極を有している。複数の永久磁石１６は、第１支持体１４の周方向において互いに隣り合う永久磁石１６の磁極（Ｎ極およびＳ極）の位置が互いに逆になるように、第１支持体１４に固定されている。すなわち、複数の永久磁石１６は、磁極の向きが交互に異なるように、第１支持体１４の周方向に沿って配置されている。 With reference to FIG. 8, the plurality of permanent magnets 16 are fixed to the outer peripheral surface of the first support 14 so as to be arranged along the circumferential direction of the first support 14. The permanent magnet 16 is fixed to the first support 14 by, for example, an adhesive. The plurality of permanent magnets 16 are arranged at equal intervals in the circumferential direction of the first support 14. Each permanent magnet 16 has an N pole on one side in the radial direction of the first support 14, and an S pole on the other side in the radial direction. The plurality of permanent magnets 16 are fixed to the first support 14 so that the positions of the magnetic poles (N pole and S pole) of the permanent magnets 16 adjacent to each other in the circumferential direction of the first support 14 are opposite to each other. There is. That is, the plurality of permanent magnets 16 are arranged along the circumferential direction of the first support 14 so that the directions of the magnetic poles are alternately different.

図８を参照して、第２支持体１８は、第１支持体１４の軸方向に延びる複数の支持部１８ａを有している。第１支持体１４の径方向において、制動ドラム１０ｃと複数の永久磁石１６との間に配置されている。複数の支持部１８ａは、第１支持体１４の周方向に沿って並ぶように、等間隔に配置されている。 With reference to FIG. 8, the second support 18 has a plurality of support portions 18a extending in the axial direction of the first support 14. It is arranged between the braking drum 10c and the plurality of permanent magnets 16 in the radial direction of the first support 14. The plurality of support portions 18a are arranged at equal intervals so as to be arranged along the circumferential direction of the first support body 14.

複数のポールピース２０はそれぞれ、第１支持体１４の周方向において隣り合う一対の支持部１８ａの間に配置されている。これにより、複数のポールピース２０は、第１支持体１４の径方向において、制動ドラム１０ｃと複数の永久磁石１６との間に配置されている。また、複数のポールピース２０は、第１支持体１４の周方向に沿って並ぶように、等間隔に配置されている。図８に示した例では、複数の永久磁石１６と同数のポールピース２０が、第２支持体１８によって支持されている。 Each of the plurality of pole pieces 20 is arranged between a pair of support portions 18a adjacent to each other in the circumferential direction of the first support body 14. As a result, the plurality of pole pieces 20 are arranged between the braking drum 10c and the plurality of permanent magnets 16 in the radial direction of the first support 14. Further, the plurality of pole pieces 20 are arranged at equal intervals so as to be arranged along the circumferential direction of the first support 14. In the example shown in FIG. 8, the same number of pole pieces 20 as the plurality of permanent magnets 16 are supported by the second support 18.

図８（ａ）を参照して、制動ドラム１０ｃの回転中に制動ドラム１０ｃを制動する際には、複数の永久磁石１６と複数のポールピース２０とが、第１支持体１４の径方向においてそれぞれ対向するように、回動ユニット１２ｂが位置付けられる。この場合、第１支持体１４と、複数の永久磁石１６と、複数のポールピース２０と、制動ドラム１０ｃとによって、図８（ａ）に矢印（実線）で示すような複数の磁気回路が形成される。これにより、複数の永久磁石１６からの磁界の作用によって、制動ドラム１０ｃの内周面に渦電流が発生する。この渦電流と、複数の永久磁石１６からの磁界との相互作用により、制動ドラム１０ｃに対して制動力が作用する。その結果、回転軸５０を減速することができる。 With reference to FIG. 8A, when braking the braking drum 10c while the braking drum 10c is rotating, the plurality of permanent magnets 16 and the plurality of pole pieces 20 are arranged in the radial direction of the first support 14. The rotating units 12b are positioned so as to face each other. In this case, the first support 14, the plurality of permanent magnets 16, the plurality of pole pieces 20, and the braking drum 10c form a plurality of magnetic circuits as shown by arrows (solid lines) in FIG. 8A. Will be done. As a result, an eddy current is generated on the inner peripheral surface of the braking drum 10c by the action of the magnetic fields from the plurality of permanent magnets 16. A braking force acts on the braking drum 10c by the interaction between this eddy current and the magnetic fields from the plurality of permanent magnets 16. As a result, the rotating shaft 50 can be decelerated.

一方、図８（ｂ）を参照して、非制動時には、複数の永久磁石１６と複数の支持部１８ａとが、第１支持体１４の径方向においてそれぞれ対向するように、回動ユニット１２ｂが位置付けられる。言い換えると、永久磁石１６が、各ポールピース２０に対して第１支持体１４の周方向にずれるように、回動ユニット１２ｂが位置付けられる。この場合、第１支持体１４と、複数の永久磁石１６と、複数のポールピース２０とによって、矢印（実線）で示すような短絡的磁気回路が形成される。この場合、制動ドラム１０ｃには、複数の永久磁石１６からの磁束が基本的には作用せず、制動ドラム１０ｃに作用する制動トルクは非常に小さくなる。なお、図８（ｂ）に矢印（破線）で示すような漏れ磁束が存在する場合には、制動トルク（引きずりトルク）が弱いながらも発生することになる。 On the other hand, with reference to FIG. 8B, the rotating unit 12b causes the rotating unit 12b so that the plurality of permanent magnets 16 and the plurality of supporting portions 18a face each other in the radial direction of the first support 14 when the brake is not applied. Positioned. In other words, the rotating unit 12b is positioned so that the permanent magnet 16 is displaced with respect to each pole piece 20 in the circumferential direction of the first support 14. In this case, the first support 14, the plurality of permanent magnets 16, and the plurality of pole pieces 20 form a short-circuit magnetic circuit as shown by an arrow (solid line). In this case, the magnetic fluxes from the plurality of permanent magnets 16 basically do not act on the braking drum 10c, and the braking torque acting on the braking drum 10c becomes very small. When the leakage flux as shown by the arrow (broken line) in FIG. 8B is present, the braking torque (dragging torque) is weak but generated.

渦電流式減速装置１００においては、制動状態と非制動状態とを切り換える際に、永久磁石１６に慣性力が作用するとともに、永久磁石１６およびポールピース２０の間で吸引力が作用する。このため、複数の永久磁石１６は、第１支持体１４に強固に支持されている必要がある。そこで、本発明者らは、上記のような構成を有する渦電流式減速装置において、複数の永久磁石を適切に支持するための方法について、種々の検討を行ってきた（例えば、特許文献１参照）。 In the eddy current type speed reducer 100, when switching between the braking state and the non-braking state, an inertial force acts on the permanent magnet 16 and an attractive force acts between the permanent magnet 16 and the pole piece 20. Therefore, the plurality of permanent magnets 16 need to be firmly supported by the first support 14. Therefore, the present inventors have conducted various studies on a method for appropriately supporting a plurality of permanent magnets in an eddy current type speed reducer having the above configuration (see, for example, Patent Document 1). ).

特開２０１５−１８０１７２号公報Japanese Unexamined Patent Publication No. 2015-180172

特許文献１に開示された渦電流式減速装置では、磁石支持リングに接着された複数の永久磁石の間に、非磁性の弾性固定部材が配置されている。この場合、制動状態と非制動状態とを切り替えた際に永久磁石に慣性力が作用しても、磁石支持リングの周方向において、弾性固定部材によって永久磁石を適切に支持することができる。その結果、永久磁石を、長期に亘って安定して磁石支持リングに固定することができる。 In the eddy current type speed reducer disclosed in Patent Document 1, a non-magnetic elastic fixing member is arranged between a plurality of permanent magnets bonded to a magnet support ring. In this case, even if an inertial force acts on the permanent magnet when switching between the braking state and the non-braking state, the permanent magnet can be appropriately supported by the elastic fixing member in the circumferential direction of the magnet support ring. As a result, the permanent magnet can be stably fixed to the magnet support ring for a long period of time.

ところで、渦電流式減速装置において本発明者らがさらに研究を進める過程で、永久磁石を支持するための固定部材を、磁石支持リングにさらに安定して固定したいという要望が出てきた。そうすることで、渦電流式減速装置の寿命をさらに向上することができるからである。 By the way, in the process of further research by the present inventors in the eddy current type speed reducer, there has been a request for more stable fixing of a fixing member for supporting a permanent magnet to a magnet support ring. By doing so, the life of the eddy current type speed reducer can be further improved.

本発明は、永久磁石を支持するための固定部材が十分な強度で固定された渦電流式減速装置、およびその製造方法を提供することを目的とする。 An object of the present invention is to provide an eddy current type speed reducer in which a fixing member for supporting a permanent magnet is fixed with sufficient strength, and a method for manufacturing the same.

本発明は、下記の渦電流式減速装置および渦電流式減速装置の製造方法を要旨とする。 The gist of the present invention is a method for manufacturing the following eddy current type reduction device and eddy current type reduction device.

（１）回転軸の回転を制動するための渦電流式減速装置であって、
前記回転軸と一体的に回転するように設けられた円筒状の制動ドラムと、
前記制動ドラムの径方向において前記制動ドラムの内側に配置され、かつ周方向に回転可能に設けられた、磁性体材料からなる円筒状の第１支持体と、
前記第１支持体の周方向に沿って並ぶように、かつ磁極の向きが交互に異なるように前記第１支持体の外周面に固定された、複数の永久磁石と、
前記複数の永久磁石の間にそれぞれ配置され、底部および前記第１支持体の軸方向に延びる一対の側壁部を有し、かつ前記底部が前記第１支持体の外周面に溶接された、非磁性体材料からなる複数の固定部材と、
前記第１支持体の径方向において、前記複数の永久磁石と前記制動ドラムとの間に設けられ、かつ前記第１支持体の周方向に沿って並ぶように設けられた複数のポールピースと、
前記複数のポールピースを支持する、非磁性体材料からなる第２支持体と、
前記複数の固定部材の前記底部と前記第１支持体との接合部にそれぞれ形成された、複数のナゲットと、を備え、
前記ナゲットを含みかつ前記第１支持体の軸方向に直交する断面において、前記底部は、前記底部の前記第１支持体とは反対側の面が凹むように、圧縮部を有する、渦電流式減速装置。 (1) An eddy current type speed reducer for braking the rotation of the rotating shaft.
A cylindrical braking drum provided to rotate integrally with the rotating shaft,
A cylindrical first support made of a magnetic material, which is arranged inside the braking drum in the radial direction of the braking drum and is rotatably provided in the circumferential direction.
A plurality of permanent magnets fixed to the outer peripheral surface of the first support so as to be arranged along the circumferential direction of the first support and the directions of the magnetic poles are alternately different.
Each of the plurality of permanent magnets has a bottom portion and a pair of side wall portions extending in the axial direction of the first support, and the bottom portion is welded to the outer peripheral surface of the first support. Multiple fixing members made of magnetic material and
A plurality of pole pieces provided between the plurality of permanent magnets and the braking drum in the radial direction of the first support and arranged so as to be arranged along the circumferential direction of the first support.
A second support made of a non-magnetic material that supports the plurality of pole pieces,
A plurality of nuggets formed at a joint portion between the bottom portion and the first support of the plurality of fixing members, respectively, are provided.
In a cross section including the nugget and orthogonal to the axial direction of the first support, the bottom portion has an eddy current type having a compression portion so that the surface of the bottom portion opposite to the first support is recessed. Speed reducer.

（２）前記圧縮部は、前記第１支持体の径方向から見て、前記ナゲットに重なるように設けられる、上記（１）に記載の渦電流式減速装置。 (2) The eddy current type speed reducer according to (1) above, wherein the compression unit is provided so as to overlap the nugget when viewed from the radial direction of the first support.

（３）前記ナゲットを含みかつ前記第１支持体の軸方向に直交する前記断面において、前記圧縮部は、前記ナゲットの一端側および他端側の少なくとも一方に設けられる、上記（１）または（２）に記載の渦電流式減速装置。 (3) In the cross section including the nugget and orthogonal to the axial direction of the first support, the compression portion is provided on at least one of one end side and the other end side of the nugget. The eddy current type speed reducer according to 2).

（４）前記第１支持体は炭素鋼からなり、
前記固定部材は、オーステナイト系ステンレス鋼からなり、
当該渦電流式減速装置は、
前記第１支持体の外周面に設けられたニッケル系めっき層と、
前記第１支持体と前記固定部材との間において前記ナゲットの周囲を覆うように形成された、前記ニッケル系めっき層の溶融凝固部とをさらに有し、
前記圧縮部は、前記第１支持体の径方向から見て、前記溶融凝固部に重なるように設けられる、上記（１）から（３）のいずれかに記載の渦電流式減速装置。 (4) The first support is made of carbon steel and is made of carbon steel.
The fixing member is made of austenitic stainless steel.
The eddy current type speed reducer is
A nickel-based plating layer provided on the outer peripheral surface of the first support and
Further having a melt-solidified portion of the nickel-based plating layer formed between the first support and the fixing member so as to cover the periphery of the nugget.
The eddy current type speed reducer according to any one of (1) to (3) above, wherein the compression portion is provided so as to overlap the melt solidification portion when viewed from the radial direction of the first support.

（５）前記ナゲットを含みかつ前記第１支持体の軸方向に直交する前記断面において、前記圧縮部は、前記溶融凝固部の一端側および他端側の少なくとも一方に設けられる、上記（４）に記載の渦電流式減速装置。 (5) In the cross section including the nugget and orthogonal to the axial direction of the first support, the compression portion is provided on at least one of one end side and the other end side of the melt solidification portion (4). The eddy current type speed reducer according to.

（６）上記（１）から（５）のいずれかに記載された渦電流式減速装置の製造方法であって、
前記固定部材の底部を前記第１支持体の外周面にスポット溶接する溶接工程と、
前記第１支持体の径方向において、前記底部の外側から押圧部材によって前記底部を押し込むことによって、前記底部に前記圧縮部を形成する押し込み工程と、
前記底部から前記押圧部材を離す除荷工程と、を備え、
前記溶接工程では、前記固定部材の底部と前記第１支持体の外周面との間に前記ナゲットが形成され、
前記押し込み工程では、前記圧縮部は、前記ナゲットを含みかつ前記第１支持体の軸方向に直交する前記渦電流式減速装置の断面において、前記底部の前記第１支持体とは反対側の面が凹むように形成される、渦電流式減速装置の製造方法。 (6) The method for manufacturing an eddy current type speed reducer according to any one of (1) to (5) above.
A welding step of spot welding the bottom of the fixing member to the outer peripheral surface of the first support, and
A pushing step of forming the compression portion on the bottom portion by pushing the bottom portion with a pressing member from the outside of the bottom portion in the radial direction of the first support.
A unloading step of separating the pressing member from the bottom portion is provided.
In the welding step, the nugget is formed between the bottom of the fixing member and the outer peripheral surface of the first support.
In the pushing step, the compression portion is a surface of the bottom portion of the eddy current type speed reducer, which includes the nugget and is orthogonal to the axial direction of the first support, opposite to the first support. A method of manufacturing an eddy current speed reducer, which is formed so as to be recessed.

本発明によれば、永久磁石を支持するための固定部材が十分な強度で固定された渦電流式減速装置を得ることができる。 According to the present invention, it is possible to obtain an eddy current type speed reducer in which a fixing member for supporting a permanent magnet is fixed with sufficient strength.

図１は、渦電流式減速装置を示す断面図である。FIG. 1 is a cross-sectional view showing an eddy current type speed reducer. 図２は、回動ユニットの一部を示す斜視図である。FIG. 2 is a perspective view showing a part of the rotating unit. 図３は、第１支持体の径方向外側から回動ユニットを見た図である。FIG. 3 is a view of the rotating unit viewed from the radial outside of the first support. 図４は、図３のＩＶ−ＩＶ線断面図である。FIG. 4 is a sectional view taken along line IV-IV of FIG. 図５は、本発明の一実施形態に係る渦電流式減速装置の製造方法を説明するための図である。FIG. 5 is a diagram for explaining a method of manufacturing an eddy current type speed reducer according to an embodiment of the present invention. 図６は、本発明の第２実施形態に係る渦電流式減速装置を説明するための図である。FIG. 6 is a diagram for explaining the eddy current type speed reducer according to the second embodiment of the present invention. 図７は、従来の渦電流式減速装置の一例を示す概略断面図である。FIG. 7 is a schematic cross-sectional view showing an example of a conventional eddy current type speed reducer. 図８は、制動ドラム、回動ユニットおよび固定ユニットの断面の一部を示す概略図である。FIG. 8 is a schematic view showing a part of a cross section of the braking drum, the rotating unit, and the fixing unit.

（第１実施形態）
以下、図面を参照しつつ、本発明の第１実施形態に係る渦電流式減速装置および固定部材の固定方法について説明する。 (First Embodiment)
Hereinafter, a method of fixing the eddy current type speed reducer and the fixing member according to the first embodiment of the present invention will be described with reference to the drawings.

（渦電流式減速装置の構成）
まず、本発明の第１実施形態に係る渦電流式減速装置の構成について説明する。図１は、本実施形態に係る渦電流式減速装置１を示す断面図である。なお、図１に示す渦電流式減速装置１が、図７に示した渦電流式減速装置１００と異なるのは、回動ユニット１２ｂ（図７参照）の代わりに、回動ユニット３０を備えている点である。したがって、以下の渦電流式減速装置１の説明においては、回動ユニット３０以外の構成についての説明は省略する。 (Configuration of eddy current speed reducer)
First, the configuration of the eddy current type speed reducer according to the first embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing an eddy current type speed reducer 1 according to the present embodiment. The eddy current type reduction device 1 shown in FIG. 1 is different from the eddy current type reduction device 100 shown in FIG. 7 by providing a rotation unit 30 instead of the rotation unit 12b (see FIG. 7). That is the point. Therefore, in the following description of the eddy current type speed reducer 1, the description of the configuration other than the rotating unit 30 will be omitted.

図２は、回動ユニット３０の一部を示す斜視図である。回動ユニット３０が、上述の回動ユニット１２ｂと異なるのは、第１支持体１４の周方向に沿って並ぶ複数の固定部材３２をさらに有している点である。固定部材３２は、非磁性体材料からなる。本実施形態では、固定部材３２は、オーステナイト系ステンレス鋼からなる。複数の固定部材３２はそれぞれ、複数の永久磁石１６の間において、第１支持体１４に固定されている。本実施形態では、後述するように、複数の固定部材３２はそれぞれ、スポット溶接によって第１支持体１４の外周面に固定されている。 FIG. 2 is a perspective view showing a part of the rotating unit 30. The rotating unit 30 differs from the above-mentioned rotating unit 12b in that it further has a plurality of fixing members 32 arranged along the circumferential direction of the first support 14. The fixing member 32 is made of a non-magnetic material. In this embodiment, the fixing member 32 is made of austenitic stainless steel. Each of the plurality of fixing members 32 is fixed to the first support 14 among the plurality of permanent magnets 16. In the present embodiment, as will be described later, each of the plurality of fixing members 32 is fixed to the outer peripheral surface of the first support 14 by spot welding.

図３は、第１支持体１４の径方向外側から回動ユニット３０を見た図であり、図４は、図３のＩＶ−ＩＶ線断面図である。なお、図４に示す断面は、第１支持体１４の軸方向に直交する断面である。 FIG. 3 is a view of the rotating unit 30 viewed from the radial outside of the first support 14, and FIG. 4 is a sectional view taken along line IV-IV of FIG. The cross section shown in FIG. 4 is a cross section orthogonal to the axial direction of the first support 14.

図２〜４を参照して、固定部材３２は、底部３４および周壁部３６を有している。周壁部３６は、底部３４の外周縁から、第１支持体１４の周方向および軸方向に広がりつつ、第１支持体１４の径方向に延びるように形成されている。すなわち、本実施形態では、固定部材３２は、バスタブ形状を有している。 With reference to FIGS. 2-4, the fixing member 32 has a bottom portion 34 and a peripheral wall portion 36. The peripheral wall portion 36 is formed so as to extend in the radial direction of the first support 14 while extending in the circumferential direction and the axial direction of the first support 14 from the outer peripheral edge of the bottom portion 34. That is, in the present embodiment, the fixing member 32 has a bathtub shape.

本実施形態では、周壁部３６は、第１支持体１４の軸方向に延びる一対の側壁部３６ａと、一対の側壁部３６ａを接続するように第１支持体１４の周方向に延びる一対の側壁部３６ｂとを含む。なお、固定部材の形状は、図２〜４に示した例に限定されない。例えば、固定部材が、一対の側壁部３６ｂを有していなくてもよい。 In the present embodiment, the peripheral wall portion 36 has a pair of side wall portions 36a extending in the axial direction of the first support 14 and a pair of side walls extending in the circumferential direction of the first support 14 so as to connect the pair of side wall portions 36a. Including part 36b. The shape of the fixing member is not limited to the examples shown in FIGS. 2 to 4. For example, the fixing member may not have a pair of side wall portions 36b.

図３および図４を参照して、本実施形態では、固定部材３２の底部３４と第１支持体１４の外周面との接合部には、スポット溶接によってナゲット３８が形成されている。図３を参照して、本実施形態では、固定部材３２ごとに、第１支持体１４の軸方向に並ぶように複数（本実施形態では２つ）のナゲット３８が形成されている。 With reference to FIGS. 3 and 4, in the present embodiment, a nugget 38 is formed by spot welding at a joint portion between the bottom portion 34 of the fixing member 32 and the outer peripheral surface of the first support 14. With reference to FIG. 3, in the present embodiment, a plurality of (two in the present embodiment) nuggets 38 are formed so as to be arranged in the axial direction of the first support 14 for each fixing member 32.

図４を参照して、ナゲット３８を含みかつ第１支持体１４の軸方向に直交する断面において、底部３４の第１支持体１４とは反対側の面が凹むように、複数の圧縮部４０が形成されている。図３を参照して、本実施形態では、一つのナゲット３８に対して、複数（本実施形態では２つ）の圧縮部４０が形成されている。圧縮部４０は、底部３４のうち、後述する押し込み工程において押圧部材４２によって押し込まれることによって圧縮された部分（圧縮凹部）である。 With reference to FIG. 4, a plurality of compression portions 40 are provided so that the surface of the bottom portion 34 opposite to the first support 14 is recessed in a cross section including the nugget 38 and orthogonal to the axial direction of the first support 14. Is formed. With reference to FIG. 3, in the present embodiment, a plurality of (two in the present embodiment) compression portions 40 are formed for one nugget 38. The compression portion 40 is a portion (compression recess) of the bottom portion 34 that is compressed by being pushed by the pressing member 42 in the pushing step described later.

図３を参照して、本実施形態では、各圧縮部４０は、第１支持体１４の径方向から見て、ナゲット３８に重なるように設けられる。また、図４に示す断面において、圧縮部４０は、ナゲット３８の一端側および他端側（第１支持体１４の周方向における一端側および他端側）に設けられる。具体的には、第１支持体１４の径方向においてナゲット３８の上記一端部および他端部に対向する位置に、それぞれ圧縮部４０が形成されている。なお、圧縮部４０は、図４に示す断面において、ナゲット３８の一端側および他端側のうちの一方のみに設けられていてもよい。また、第１支持体１４の径方向から見た場合に、ナゲット３８の中心に重なるように圧縮部４０が形成されてもよい。 With reference to FIG. 3, in the present embodiment, each compression unit 40 is provided so as to overlap the nugget 38 when viewed from the radial direction of the first support 14. Further, in the cross section shown in FIG. 4, the compression portion 40 is provided on one end side and the other end side (one end side and the other end side in the circumferential direction of the first support 14) of the nugget 38. Specifically, compression portions 40 are formed at positions facing the one end and the other end of the nugget 38 in the radial direction of the first support 14. The compression unit 40 may be provided on only one of the one end side and the other end side of the nugget 38 in the cross section shown in FIG. Further, the compression portion 40 may be formed so as to overlap the center of the nugget 38 when viewed from the radial direction of the first support 14.

図３を参照して、本実施形態では、圧縮部４０は、第１支持体１４の径方向から見た場合に円形状を有している。ただし、圧縮部４０の形状は図３の例に限定されない。例えば、圧縮部は、第１支持体１４の径方向から見た場合に、第１支持体１４の軸方向に延びる長円形状または楕円形状を有していてもよい。 With reference to FIG. 3, in the present embodiment, the compression unit 40 has a circular shape when viewed from the radial direction of the first support 14. However, the shape of the compression unit 40 is not limited to the example of FIG. For example, the compression portion may have an oval shape or an elliptical shape extending in the axial direction of the first support 14 when viewed from the radial direction of the first support 14.

（渦電流式減速装置の製造方法）
次に、本発明の一実施形態に係る渦電流式減速装置の製造方法について説明する。図５は、本発明の一実施形態に係る渦電流式減速装置の製造方法を説明するための図であり、図５（ａ）は、溶接工程を示す図であり、図５（ｂ）は、押し込み工程を示す図であり、図５（ｃ）は、除荷工程を示す図である。 (Manufacturing method of eddy current type speed reducer)
Next, a method of manufacturing the eddy current type speed reducer according to the embodiment of the present invention will be described. 5A and 5B are diagrams for explaining a method for manufacturing an eddy current type speed reducer according to an embodiment of the present invention, FIG. 5A is a diagram showing a welding process, and FIG. 5B is a diagram showing a welding process. , It is a figure which shows the pushing process, and FIG. 5C is a figure which shows the unloading process.

本実施形態に係る渦電流式減速装置は、以下に説明する固定部材の固定方法（溶接工程、押し込み工程、および除荷工程）を経て製造された回動ユニットを用いて製造される。渦電流式減速装置を製造するに際して、以下に説明する固定方法以外の工程については、公知の種々の工程を利用できる。したがって、以下においては、渦電流式減速装置の製造工程のうち、固定方法以外の工程についての説明は省略する。 The eddy current type speed reducer according to the present embodiment is manufactured by using a rotating unit manufactured through the fixing method (welding step, pushing step, and unloading step) of the fixing member described below. In manufacturing the eddy current type speed reducer, various known steps can be used for steps other than the fixing method described below. Therefore, in the following, the description of the steps other than the fixing method among the manufacturing steps of the eddy current type speed reducer will be omitted.

図５（ａ）を参照して、本実施形態に係る固定方法では、まず、公知の方法によって、固定部材３２の底部３４を、第１支持体１４の外周面にスポット溶接する（溶接工程）。この溶接工程によって、底部３４と第１支持体１４の外周面との間に、ナゲット３８が形成される。図３に示した回動ユニット３０を製造する際には、固定部材３２ごとに、２回の溶接工程が行われる。すなわち、固定部材３２ごとに、２つのナゲット３８が形成される。 In the fixing method according to the present embodiment with reference to FIG. 5A, first, the bottom portion 34 of the fixing member 32 is spot-welded to the outer peripheral surface of the first support 14 by a known method (welding step). .. By this welding process, a nugget 38 is formed between the bottom portion 34 and the outer peripheral surface of the first support 14. When manufacturing the rotating unit 30 shown in FIG. 3, two welding steps are performed for each fixing member 32. That is, two nuggets 38 are formed for each fixing member 32.

次に、図５（ｂ）を参照して、第１支持体１４の径方向において底部３４の外側から、押圧部材４２を底部３４に押し込むことによって、底部３４に圧縮部４０を形成する（押し込み工程）。押し込み工程においては、底部３４のうち、押圧部材４２によって押された部分が、塑性変形する。具体的には、押圧部材４２によって押された部分が、第１支持体１４の周方向に延びるように変形する。これにより、押圧部材４２によって押された部分に、上記周方向の引張応力および引張塑性ひずみが生じる。なお、図５（ｂ）においては、図面が煩雑になることを避けるために、引張応力を示す矢印を第１支持体１４上に示しているが、引張応力は、底部３４において発生している。図５（ｃ）における圧縮応力についても同様である。 Next, referring to FIG. 5B, the pressing member 42 is pushed into the bottom 34 from the outside of the bottom 34 in the radial direction of the first support 14, thereby forming the compression portion 40 in the bottom 34 (pushing). Process). In the pushing step, the portion of the bottom portion 34 pushed by the pressing member 42 is plastically deformed. Specifically, the portion pushed by the pressing member 42 is deformed so as to extend in the circumferential direction of the first support 14. As a result, the tensile stress and the tensile plastic strain in the circumferential direction are generated in the portion pressed by the pressing member 42. In FIG. 5B, an arrow indicating tensile stress is shown on the first support 14 in order to avoid complicating the drawing, but the tensile stress is generated at the bottom 34. .. The same applies to the compressive stress in FIG. 5 (c).

次に、図５（ｃ）を参照して、底部３４から押圧部材４２を離す（除荷工程）。この除荷工程において、スプリングバック現象によって、圧縮部４０に、第１支持体１４の周方向において圧縮残留応力が生じる。押し込み工程および除荷工程は、形成される圧縮部４０の数に応じて繰り返し実行される。 Next, referring to FIG. 5C, the pressing member 42 is separated from the bottom portion 34 (unloading step). In this unloading step, a compression residual stress is generated in the compression portion 40 in the circumferential direction of the first support 14 due to the springback phenomenon. The pushing step and the unloading step are repeatedly executed according to the number of compression portions 40 formed.

なお、詳細な説明は省略するが、複数の永久磁石１６は、複数の固定部材３２を第１支持体１４に固定する前に、第１支持体１４に接着してもよく、複数の固定部材３２を第１支持体１４に固定した後に、第１支持体１４に接着してもよい。 Although detailed description will be omitted, the plurality of permanent magnets 16 may be adhered to the first support 14 before fixing the plurality of fixing members 32 to the first support 14, and the plurality of fixing members may be adhered to the first support 14. After fixing 32 to the first support 14, it may be adhered to the first support 14.

（本実施形態の効果）
以上のように、本実施形態においては、圧縮部４０に圧縮残留応力を発生させることができる。これにより、固定部材３２が第１支持体１４から外れることを十分に抑制することができる。具体的には、渦電流式減速装置１を制動状態と非制動状態との間で切り換える際には、固定部材３２に、第１支持体１４の周方向への衝撃荷重が付加される。言い換えると、固定部材３２を第１支持体１４から剥がすように働く力が、固定部材３２に付加される。これにより、固定部材３２の底部３４には、第１支持体１４の周方向において引張荷重が付与される。しかし、上記のように、本実施形態では、圧縮部４０に圧縮残留応力が付与されているので、底部３４に引張荷重が付与されても、底部３４（特に、応力が集中しやすいナゲット３８の周辺部）において大きな引張応力が生じることを防止することができる。これにより、固定部材３２と第１支持体１４との接合強度を十分に向上させることができる。また、底部３４のうちナゲット３８の周辺部において亀裂が生じることを十分に抑制できる。これらの結果、固定部材３２と第１支持体１４との接合部の疲労強度を向上させることができ、渦電流式減速装置１の寿命を向上させることができる。 (Effect of this embodiment)
As described above, in the present embodiment, the compression residual stress can be generated in the compression unit 40. As a result, it is possible to sufficiently prevent the fixing member 32 from coming off from the first support 14. Specifically, when the eddy current type speed reducer 1 is switched between the braking state and the non-braking state, an impact load in the circumferential direction of the first support 14 is applied to the fixing member 32. In other words, a force acting to peel the fixing member 32 from the first support 14 is applied to the fixing member 32. As a result, a tensile load is applied to the bottom portion 34 of the fixing member 32 in the circumferential direction of the first support 14. However, as described above, in the present embodiment, since the compression residual stress is applied to the compression portion 40, even if a tensile load is applied to the bottom portion 34, the bottom portion 34 (particularly, the nugget 38 in which the stress tends to concentrate) It is possible to prevent a large tensile stress from being generated in the peripheral portion). Thereby, the joint strength between the fixing member 32 and the first support 14 can be sufficiently improved. Further, it is possible to sufficiently suppress the occurrence of cracks in the peripheral portion of the nugget 38 out of the bottom portion 34. As a result, the fatigue strength of the joint portion between the fixing member 32 and the first support 14 can be improved, and the life of the eddy current type speed reducer 1 can be improved.

なお、渦電流式減速装置１においては、制動状態から非制動状態へ切り替える時と、非制動状態から制動状態へ切り替える時とでは、第１支持体１４の回動方向が反対になる。このため、ナゲット３８の周囲において最大の応力が発生する位置は、制動状態から非制動状態へ切り替える時と、非制動状態から制動状態へ切り替える時とで異なる。具体的には、制動状態から非制動状態へ切り替える時と、非制動状態から制動状態へ切り替える時とで、上記最大応力が発生する位置は、円形のナゲット３８の周囲において、１８０度離れた位置になる。 In the eddy current type speed reducer 1, the rotation direction of the first support 14 is opposite when switching from the braking state to the non-braking state and when switching from the non-braking state to the braking state. Therefore, the position where the maximum stress is generated around the nugget 38 differs between the time of switching from the braking state to the non-braking state and the time of switching from the non-braking state to the braking state. Specifically, the position where the maximum stress is generated when switching from the braking state to the non-braking state and when switching from the non-braking state to the braking state is a position 180 degrees apart around the circular nugget 38. become.

また、永久磁石１６から固定部材３２に加わる衝撃荷重の大きさは、制動状態から非制動状態へ切り替える時と、非制動状態から制動状態へ切り替える時とで異なる。ロータ１０の回転数が低い時は、制動状態から非制動状態へ切り替える時に大きな衝撃荷重が固定部材３２に加わる。一方、ロータ１０の回転数が高い時は、非制動状態から制動状態へ切り替える時に大きな衝撃荷重が固定部材３２に加わる。 Further, the magnitude of the impact load applied from the permanent magnet 16 to the fixing member 32 differs depending on whether the braking state is switched to the non-braking state or the non-braking state is switched to the braking state. When the rotation speed of the rotor 10 is low, a large impact load is applied to the fixing member 32 when switching from the braking state to the non-braking state. On the other hand, when the rotation speed of the rotor 10 is high, a large impact load is applied to the fixing member 32 when switching from the non-braking state to the braking state.

したがって、ロータ１０の回転数が低い領域でのみ使用される渦電流式減速装置１では、制動状態から非制動状態へ切り替える時に最大応力が発生する位置のみに圧縮部４０を形成すればよい。一方、ロータ１０の回転数が高い領域まで使用される渦電流式減速装置１では、ナゲット３８の周囲において最大応力が発生する２箇所に圧縮部４０を形成することが好ましい。 Therefore, in the eddy current type speed reducer 1 used only in the region where the rotation speed of the rotor 10 is low, the compression unit 40 may be formed only at the position where the maximum stress is generated when switching from the braking state to the non-braking state. On the other hand, in the eddy current type speed reducer 1 used up to the region where the rotation speed of the rotor 10 is high, it is preferable to form the compression portions 40 at two places where the maximum stress is generated around the nugget 38.

（第２実施形態）
第１支持体１４を炭素鋼によって形成する場合、長期間使用すると、第１支持体１４の表面に錆が発生するおそれがある。そこで、本発明者らは、錆の発生を防止するために、第１支持体１４の外周面にニッケル系めっき層を形成することを試みた。しかしながら、この場合、固定部材３２を第１支持体１４にスポット溶接する際に、第１支持体１４と固定部材３２との間において、ナゲット３８の周囲を覆うようにニッケル系めっき層の溶融凝固部が形成されることが分かった。さらに、渦電流式減速装置を制動状態と非制動状態との間で切り換える際に、固定部材３２の底部３４のうち、上記溶融凝固部の周辺において応力集中が発生する場合があることが分かった。以下において説明する渦電流式減速装置は、これらの知見に基づいて発明されたものである。 (Second Embodiment)
When the first support 14 is made of carbon steel, rust may occur on the surface of the first support 14 after long-term use. Therefore, the present inventors have attempted to form a nickel-based plating layer on the outer peripheral surface of the first support 14 in order to prevent the occurrence of rust. However, in this case, when the fixing member 32 is spot welded to the first support 14, the nickel-based plating layer is melt-solidified between the first support 14 and the fixing member 32 so as to cover the periphery of the nugget 38. It was found that a part was formed. Further, it was found that when the eddy current type speed reducer is switched between the braking state and the non-braking state, stress concentration may occur in the vicinity of the melt-solidified portion in the bottom portion 34 of the fixing member 32. .. The eddy current type speed reducer described below was invented based on these findings.

図６は、本発明の第２実施形態に係る渦電流式減速装置を説明するための図であり、図６（ａ）は、本発明の第２実施形態に係る渦電流式減速装置の回動ユニットを示す拡大図であり、図６（ｂ）は、回動ユニットの他の例を示す拡大図であり、図６（ｃ）は、回動ユニットのさらに他の例を示す拡大図である。なお、図６においては、回動ユニットのうち、ナゲット３８の周辺のみを示している。 FIG. 6 is a diagram for explaining the eddy current type speed reducer according to the second embodiment of the present invention, and FIG. 6A is a rotation of the eddy current type speed reducer according to the second embodiment of the present invention. FIG. 6 (b) is an enlarged view showing another example of the rotating unit, and FIG. 6 (c) is an enlarged view showing still another example of the rotating unit. is there. Note that FIG. 6 shows only the periphery of the nugget 38 among the rotating units.

上述の第１実施形態に係る渦電流式減速装置１と、第２実施形態に係る渦電流式減速装置とでは、回動ユニットの構成が異なる。具体的には、図６（ａ）に示すように、本実施形態に係る回動ユニット３０ａでは、第１支持体１４の外周面に、ニッケル系めっき層４４が形成されている。また、第１支持体１４と固定部材３２（より具体的には底部３４）との間において、ナゲット３８の周囲を覆うように、ニッケル系めっき層の溶融凝固部４６が形成されている。 The configuration of the rotating unit is different between the eddy current type speed reducer 1 according to the first embodiment and the eddy current type speed reducer according to the second embodiment. Specifically, as shown in FIG. 6A, in the rotating unit 30a according to the present embodiment, the nickel-based plating layer 44 is formed on the outer peripheral surface of the first support 14. Further, a melt-solidified portion 46 of the nickel-based plating layer is formed between the first support 14 and the fixing member 32 (more specifically, the bottom portion 34) so as to cover the periphery of the nugget 38.

図６（ａ）に示すように、本実施形態では、ナゲット３８を含みかつ第１支持体１４の軸方向に直交する断面において、圧縮部４０は、溶融凝固部４６の一端側および他端側（第１支持体１４の周方向における一端側および他端側）に設けられる。具体的には、第１支持体１４の径方向において、溶融凝固部４６の上記一端部および他端部に対向する位置にそれぞれ圧縮部４０が形成されている。言い換えると、圧縮部４０は、第１支持体１４の径方向においてニッケル系めっき層４４と溶融凝固部４６との境界部に対向する位置に形成されている。本実施形態では、圧縮部４０は、第１支持体１４の径方向から見て、溶融凝固部４６に重なるように設けられている。圧縮部４０は、第１実施形態と同様に形成される。これにより、圧縮部４０近傍には、圧縮残留応力が付与されている。 As shown in FIG. 6A, in the present embodiment, in the cross section including the nugget 38 and orthogonal to the axial direction of the first support 14, the compression portion 40 is on one end side and the other end side of the melt solidification portion 46. (One end side and the other end side in the circumferential direction of the first support 14) are provided. Specifically, in the radial direction of the first support 14, compression portions 40 are formed at positions facing the one end portion and the other end portion of the melt solidification portion 46, respectively. In other words, the compression portion 40 is formed at a position facing the boundary portion between the nickel-based plating layer 44 and the melt-solidification portion 46 in the radial direction of the first support 14. In the present embodiment, the compression unit 40 is provided so as to overlap the melt solidification unit 46 when viewed from the radial direction of the first support 14. The compression unit 40 is formed in the same manner as in the first embodiment. As a result, compressive residual stress is applied in the vicinity of the compression unit 40.

本実施形態では、底部３４に引張荷重が付与されたとしても、圧縮部４０近傍に圧縮残留応力が付与されているので、底部３４のうちニッケル系めっき層４４と溶融凝固部４６との境界部近傍において大きな引張応力が生じることを防止することができる。これにより、固定部材３２と第１支持体１４との接合強度を十分に向上させることができる。また、底部３４のうち溶融凝固部４６の周辺部において亀裂が生じることを十分に抑制できる。これらの結果、固定部材３２と第１支持体１４との接合部の疲労強度を向上させることができ、渦電流式減速装置の寿命を向上させることができる。 In the present embodiment, even if a tensile load is applied to the bottom portion 34, since the compressive residual stress is applied in the vicinity of the compression portion 40, the boundary portion between the nickel-based plating layer 44 and the melt-solidification portion 46 of the bottom portion 34. It is possible to prevent a large tensile stress from being generated in the vicinity. Thereby, the joint strength between the fixing member 32 and the first support 14 can be sufficiently improved. Further, it is possible to sufficiently suppress the occurrence of cracks in the peripheral portion of the melt-solidified portion 46 of the bottom portion 34. As a result, the fatigue strength of the joint between the fixing member 32 and the first support 14 can be improved, and the life of the eddy current type speed reducer can be improved.

なお、上述の第１実施形態と同様に、一つのナゲット３８に対して複数の圧縮部４０が設けられていてもよく、一つのナゲット３８に対して一つの圧縮部４０が設けられてもよい。 As in the first embodiment described above, a plurality of compression units 40 may be provided for one nugget 38, or one compression unit 40 may be provided for one nugget 38. ..

また、圧縮部４０が形成される位置は、上述の例に限定されない。例えば、図６（ｂ）に示す回動ユニット３０ｂのように、第１支持体１４の径方向においてナゲット３８の一端部および他端部（第１支持体１４の周方向における一端部および他端部）に対向する位置に、それぞれ圧縮部４０が形成されてもよい。言い換えると、圧縮部４０は、第１支持体１４の径方向において溶融凝固部４６とナゲット３８との境界部に対向する位置に形成されてもよい。また、図６（ｃ）に示す回動ユニット３０ｃのように、ニッケル系めっき層４４と溶融凝固部４６との境界部およびニッケル系めっき層４４とナゲット３８との境界部に対向する大きさの圧縮部４０を形成してもよい。 Further, the position where the compression portion 40 is formed is not limited to the above example. For example, as in the rotating unit 30b shown in FIG. 6B, one end and the other end of the nugget 38 in the radial direction of the first support 14 (one end and the other end in the circumferential direction of the first support 14). The compression portions 40 may be formed at positions facing the portions). In other words, the compression portion 40 may be formed at a position facing the boundary portion between the melt solidification portion 46 and the nugget 38 in the radial direction of the first support 14. Further, as in the rotation unit 30c shown in FIG. 6C, the size of the rotation unit is such that it faces the boundary between the nickel-based plating layer 44 and the melt-solidified portion 46 and the boundary between the nickel-based plating layer 44 and the nugget 38. The compression unit 40 may be formed.

（実験）
第２実施形態で説明した回動ユニットの疲労強度を評価するために以下の実験（疲労試験）を行なった。 (Experiment)
The following experiment (fatigue test) was performed to evaluate the fatigue strength of the rotating unit described in the second embodiment.

まず、外径３５０ｍｍ、厚さ１０ｍｍの円筒形の第１支持体１４を１１本用意した。各第１支持体１４に、厚さ１０μｍのニッケル系めっきを施した。ニッケル系めっきを施した第１支持体１４の外周面に、図２に示したバスタブ形状を有する固定部材３２をスポット溶接によって固定した。具体的には、図３に示した回動ユニット３０と同様に、底部３４の２箇所をスポット溶接によって第１支持体１４に溶接した。固定部材３２は、厚さ０．３ｍｍのオーステナイト系ステンレス鋼板をプレス成形することにより作製した。 First, 11 cylindrical first supports 14 having an outer diameter of 350 mm and a thickness of 10 mm were prepared. Each first support 14 was subjected to nickel-based plating having a thickness of 10 μm. A fixing member 32 having a bathtub shape shown in FIG. 2 was fixed to the outer peripheral surface of the first support 14 plated with nickel by spot welding. Specifically, similarly to the rotating unit 30 shown in FIG. 3, two points of the bottom portion 34 were welded to the first support 14 by spot welding. The fixing member 32 was manufactured by press-molding an austenitic stainless steel plate having a thickness of 0.3 mm.

１１本の第１支持体１４のうち、３本の第１支持体１４には、圧縮部４０を形成しなかった。残りの８本の第１支持体１４については、スポット溶接後に、図５で説明した方法によって固定部材３２の底部３４に圧縮部４０を形成した。具体的には、ナゲット３８ごとに、一つの圧縮部４０を形成した。したがって、各固定部材３２において、２つの圧縮部４０を形成した。圧縮部４０は、疲労試験において、荷重が加えられる側壁部３６ａ側に形成した。 Of the 11 first supports 14, three first supports 14 did not form the compression portion 40. For the remaining eight first supports 14, after spot welding, a compression portion 40 was formed on the bottom 34 of the fixing member 32 by the method described with reference to FIG. Specifically, one compression unit 40 was formed for each nugget 38. Therefore, two compression portions 40 are formed in each fixing member 32. The compression portion 40 was formed on the side wall portion 36a to which a load is applied in the fatigue test.

疲労試験では，固定部材３２の一方側壁部３６ａ（図４参照）に対して、第１支持体１４の周方向に繰り返しの荷重（４００Ｎ）を負荷した。試験結果および圧縮部の形状を、下記の表１に示す。 In the fatigue test, a repeated load (400N) was applied to one side wall portion 36a (see FIG. 4) of the fixing member 32 in the circumferential direction of the first support 14. The test results and the shape of the compression part are shown in Table 1 below.

表１に示すように、圧縮部４０を形成しなかった試験Ｎｏ．１〜３では、９．８〜１８．５万回の繰り返し荷重により、固定部材３２に亀裂が発生した。一方、圧縮部を形成した試験Ｎｏ．４〜１１では、試験Ｎｏ．１〜３に比べて、疲労寿命が大幅に向上した。特に、試験Ｎｏ．５〜１１では、繰り返し荷重を２００万回負荷しても亀裂が発生しなかった。 As shown in Table 1, the test No. 1 in which the compression portion 40 was not formed. In Nos. 1 to 3, cracks were generated in the fixing member 32 due to repeated loads of 98 to 185,000 times. On the other hand, the test No. in which the compressed portion was formed. In 4 to 11, test No. Fatigue life was significantly improved as compared with 1-3. In particular, Test No. In 5 to 11, cracks did not occur even when the repeated load was applied 2 million times.

以上の結果から、本発明の実施の形態に係る回動ユニットでは、第１支持体１４と固定部材３２との接合部の疲労寿命が十分に向上していることが分かる。 From the above results, it can be seen that in the rotating unit according to the embodiment of the present invention, the fatigue life of the joint portion between the first support 14 and the fixing member 32 is sufficiently improved.

以上のように、本発明によれば、永久磁石を支持するための固定部材が十分な強度で固定された渦電流式減速装置を得ることができる。 As described above, according to the present invention, it is possible to obtain an eddy current type speed reducer in which a fixing member for supporting a permanent magnet is fixed with sufficient strength.

１渦電流式減速装置
１０ロータ
１２ステータ
１４第１支持体１４
１６永久磁石
１８第２支持体
２０ポールピース
３０，３０ａ，３０ｂ，３０ｃ回動ユニット
３２固定部材
３４底部
３６周壁部
３８ナゲット
４０圧縮部
４２押圧部材
４４ニッケル系めっき層
４６溶融凝固部 1 Eddy current type speed reducer 10 Rotor 12 Stator 14 First support 14
16 Permanent magnet 18 Second support 20 Pole piece 30, 30a, 30b, 30c Rotating unit 32 Fixing member 34 Bottom 36 Peripheral wall 38 Nugget 40 Compression part 42 Pressing member 44 Nickel-based plating layer 46 Melt solidification part

Claims

An eddy current speed reducer for braking the rotation of the rotating shaft.
A cylindrical braking drum provided to rotate integrally with the rotating shaft,
A cylindrical first support made of a magnetic material, which is arranged inside the braking drum in the radial direction of the braking drum and is rotatably provided in the circumferential direction.
A plurality of permanent magnets fixed to the outer peripheral surface of the first support so as to be arranged along the circumferential direction of the first support and the directions of the magnetic poles are alternately different.
Each of the plurality of permanent magnets has a bottom portion and a pair of side wall portions extending in the axial direction of the first support, and the bottom portion is welded to the outer peripheral surface of the first support. Multiple fixing members made of magnetic material and
A plurality of pole pieces provided between the plurality of permanent magnets and the braking drum in the radial direction of the first support and arranged so as to be arranged along the circumferential direction of the first support.
A second support made of a non-magnetic material that supports the plurality of pole pieces,
A plurality of nuggets formed at a joint portion between the bottom portion and the first support of the plurality of fixing members, respectively, are provided.
In a cross section perpendicular to the axial direction of contain and said first support member to the nugget, the bottom, the so recessed that the surface opposite to the bottom portion of the first support, have a compression unit,
The compression unit is an eddy current type speed reducer provided so as to overlap the nugget when viewed from the radial direction of the first support.

The eddy current type according to claim 1, wherein the compression portion is provided on at least one of one end side and the other end side of the nugget in the cross section including the nugget and orthogonal to the axial direction of the first support. Deceleration device.

An eddy current speed reducer for braking the rotation of the rotating shaft.
A cylindrical braking drum provided to rotate integrally with the rotating shaft,
A cylindrical first support made of a magnetic material, which is arranged inside the braking drum in the radial direction of the braking drum and is rotatably provided in the circumferential direction.
A plurality of permanent magnets fixed to the outer peripheral surface of the first support so as to be arranged along the circumferential direction of the first support and the directions of the magnetic poles are alternately different.
Each of the plurality of permanent magnets has a bottom portion and a pair of side wall portions extending in the axial direction of the first support, and the bottom portion is welded to the outer peripheral surface of the first support. Multiple fixing members made of magnetic material and
A plurality of pole pieces provided between the plurality of permanent magnets and the braking drum in the radial direction of the first support and arranged so as to be arranged along the circumferential direction of the first support.
A second support made of a non-magnetic material that supports the plurality of pole pieces,
A plurality of nuggets formed at a joint portion between the bottom portion and the first support of the plurality of fixing members, respectively, are provided.
The first support is made of carbon steel and is made of carbon steel.
The fixing member is made of austenitic stainless steel.
Nickel-based plating layer is provided on the outer peripheral surface of the front Symbol first support,
The melt-solidified portions of the way before Symbol nickel plated layer covering the periphery of the nugget is formed between the first substrate and the fixing member,
In a cross section including the nugget and orthogonal to the axial direction of the first support, the bottom has a compression portion so that the surface of the bottom opposite to the first support is recessed.
The compression portion is an eddy current type speed reducer provided so as to overlap the melt solidification portion when viewed from the radial direction of the first support.

The eddy current type speed reducer according to claim 3 , wherein the compression unit is provided so as to overlap the nugget when viewed from the radial direction of the first support.

The third or fourth aspect of the cross section including the nugget and orthogonal to the axial direction of the first support, wherein the compression portion is provided on at least one of one end side and the other end side of the melt solidification portion. Eddy current type speed reducer.

The method for manufacturing an eddy current type speed reducer according to any one of claims 1 to 5.
A welding step of spot welding the bottom of the fixing member to the outer peripheral surface of the first support, and
A pushing step of forming the compression portion on the bottom portion by pushing the bottom portion with a pressing member from the outside of the bottom portion in the radial direction of the first support.
A unloading step of separating the pressing member from the bottom portion is provided.
In the welding step, the nugget is formed between the bottom of the fixing member and the outer peripheral surface of the first support.
In the pushing step, the compression portion is a surface of the bottom portion of the eddy current type speed reducer, which includes the nugget and is orthogonal to the axial direction of the first support, opposite to the first support. A method of manufacturing an eddy current speed reducer, which is formed so as to be recessed.