JPH05113377A - Magnetostriction type torque sensor - Google Patents
Magnetostriction type torque sensorInfo
- Publication number
- JPH05113377A JPH05113377A JP3302423A JP30242391A JPH05113377A JP H05113377 A JPH05113377 A JP H05113377A JP 3302423 A JP3302423 A JP 3302423A JP 30242391 A JP30242391 A JP 30242391A JP H05113377 A JPH05113377 A JP H05113377A
- Authority
- JP
- Japan
- Prior art keywords
- side wall
- shield yoke
- elastic
- spacer
- edge portion
- 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
Landscapes
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、トルク伝達軸に印加さ
れるトルクを非接触検出する磁歪式トルクセンサに関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetostrictive torque sensor for non-contact detection of torque applied to a torque transmission shaft.
【0002】[0002]
【従来の技術】磁歪式トルクセンサは、トルク伝達軸
(以下、「軸体」ともいう)にトルクが印加されると、
軸体の表面(予め一軸磁気異方性が付与されている)
に、トルクの大きさに比例する透磁率の変化が生じるこ
とを利用し、その透磁率の変化を電気量として検出する
ようにした非接触型のトルクセンサである。2. Description of the Related Art A magnetostrictive torque sensor, when torque is applied to a torque transmission shaft (hereinafter, also referred to as "shaft"),
Surface of shaft (uniaxial magnetic anisotropy is given in advance)
In addition, the non-contact type torque sensor is adapted to detect the change of the magnetic permeability as an electric quantity by utilizing the change of the magnetic permeability which is proportional to the magnitude of the torque.
【0003】図9、および図10にそのトルクセンサの
構造を示す。10は励磁・検出巻線であり、軸体Sの表
面に励磁磁界を印加する巻線10・1と、軸体表面に生
じる透磁率の変化を検出する巻線10・2とからなり、
これらはボビン20に積層巻装されている。励磁巻線1
0・1には高周波励磁電源が、検出巻線10・2には、
検出される透磁率の変化を電気量(例えば直流電圧)と
して出力する検出回路が、それぞれ接続される。なお、
図は、軸体表面の透磁率の変化を差動的に取出すための
2つの励磁・検出巻線10,10が適当な距離をおいて
並列配置された差動型センサを示している。9 and 10 show the structure of the torque sensor. Reference numeral 10 denotes an excitation / detection winding, which is composed of a winding 10.1 for applying an exciting magnetic field to the surface of the shaft S and a winding 10.2 for detecting a change in magnetic permeability generated on the surface of the shaft.
These are laminated and wound around the bobbin 20. Excitation winding 1
A high-frequency excitation power supply is used for the 0. 1 and a detection winding 10.
A detection circuit that outputs the detected change in magnetic permeability as an electric quantity (for example, a DC voltage) is connected. In addition,
The figure shows a differential type sensor in which two exciting / detecting windings 10 and 10 for differentially extracting a change in magnetic permeability of the shaft surface are arranged in parallel at an appropriate distance.
【0004】30は、上記励磁・検出巻線10を囲包す
る強磁性材料(例えばパーマロイ合金)で形成されたシ
ールドヨークである。シールドヨーク30は、中央に軸
方向の貫通孔(軸体Sの挿通孔)33を有し、内部に励
磁・検出巻線10を嵌納する円周溝34が設けられた2
つの半円状割部材30・1と30・2からなり、励磁・
検出巻線10を嵌納して円筒体に組付けられる(図1
0)。Reference numeral 30 is a shield yoke formed of a ferromagnetic material (for example, permalloy alloy) surrounding the excitation / detection winding 10. The shield yoke 30 has a through hole (insertion hole of the shaft body S) 33 in the axial direction at the center thereof, and a circumferential groove 34 into which the excitation / detection winding 10 is fitted is provided inside the shield yoke 30.
It consists of two semicircular split members 30.1 and 30.2.
The detection winding 10 is fitted into the cylindrical body (FIG. 1).
0).
【0005】励磁・検出巻線10を囲包したシールドヨ
ーク30は、その両端の円周稜部にスペーサ40が環着
されてハウジング50の円筒状空間内に固定される。ス
ペーサ40は、円周縁部40aとこれに直交する向きの
側壁縁部40bとがなす略L字形の断面形状を有する円
環部材であり、ゴムまたは樹脂(テフロン等)の弾性材
料で形成されている。そのスペーサ40は、取扱い性お
よびシールドヨーク30に対する装着操作性の観点か
ら、例えば1.5mmないしそれ以上の肉厚に形成され
たものが使用されている。The shield yoke 30 surrounding the excitation / detection winding 10 is fixed in the cylindrical space of the housing 50 with spacers 40 ring-attached to the circumferential ridges at both ends thereof. The spacer 40 is an annular member having a substantially L-shaped cross section formed by a circular peripheral portion 40a and a side wall edge portion 40b in a direction orthogonal to the circular peripheral portion 40a, and is made of an elastic material such as rubber or resin (Teflon or the like). There is. As the spacer 40, one having a wall thickness of, for example, 1.5 mm or more is used from the viewpoint of handleability and mounting operability with respect to the shield yoke 30.
【0006】シールドヨーク30が内装されたハウジン
グ50は、その左右の開口端部の内周面に形成されてい
る段差部に軸受60,60が(一方の段差部には当て板
リング52が介装されて)嵌め込まれ、軸受60,60
を介して軸体Sに回転対称に取付けられる。In the housing 50 in which the shield yoke 30 is installed, bearings 60, 60 are provided in a step portion formed on the inner peripheral surfaces of the left and right opening ends (the contact plate ring 52 is interposed in one step portion). Mounted) and fitted into the bearing 60, 60
It is attached to the shaft S through the shaft in a rotationally symmetrical manner.
【0007】[0007]
【発明が解決しようとする課題】上記トルクセンサの実
使用における問題として、トルク検出々力の変動を生じ
易いことが挙げられる。そのトルク出力変動の主たる原
因は、ハウジング50内におけるシールドヨーク30の
固定構造の不安定性にある。すなわち、シールドヨーク
30は、その両端に環着された弾性体スペーサ40,4
0をハウジング50の内周面に対する着地部材としてそ
の筒状空間内に保持されているだけの固定構造であるた
め、安定性に乏しく、軸体Sの高速度回転に伴う振動や
衝撃による位置変動を生じ易い。殊に、回転の起動・停
止時等の強い衝撃が加わると、スペーサ40に瞬間的に
ねじれ等の変形を生じ易く、その変形状態がスペーサ4
0とシールドヨーク30の界面の摩擦抵抗のためにその
まゝ保持されると、シールドヨーク30の軸心(従つて
その内部に嵌納された励磁・検出巻線10の軸心)が軸
体Sの軸心からずれた状態でトルクの検出が行なわれる
ことになり、信頼性のあるトルク検出は不可能となつて
しまう。A problem in the actual use of the torque sensor is that the torque detection force tends to fluctuate. The main cause of the torque output fluctuation is the instability of the fixing structure of the shield yoke 30 in the housing 50. That is, the shield yoke 30 has the elastic spacers 40, 4 annularly attached to both ends thereof.
Since 0 is a fixed structure in which it is held in the cylindrical space as a landing member for the inner peripheral surface of the housing 50, the stability is poor, and the position variation due to vibration or shock accompanying the high speed rotation of the shaft S is caused. Is likely to occur. In particular, when a strong impact is applied at the time of starting / stopping rotation, the spacer 40 is apt to be momentarily deformed, such as twisted.
0 is held as it is due to frictional resistance at the interface between the shield yoke 30 and the shield yoke 30, the shaft center of the shield yoke 30 (and hence the shaft center of the excitation / detection winding 10 fitted therein) is The torque is detected in a state where it is deviated from the axis of S, which makes reliable torque detection impossible.
【0008】このシールドヨーク30の位置変動防止策
として、弾性体スペーサ40の使用を廃し、例えば焼嵌
め等によりシールドヨーク30をハウジング50内に締
め付け固定する構造とすることも考えられるが、そのよ
うな構造ではシールドヨーク30の位置変動の防止はで
きても、締め付け構造であるためにシールドヨーク30
に内部応力を生じ、シールドヨーク30の磁気遮蔽機能
や磁路としての効果に変化をきたすため、トルク検出特
性の低下を免れず、本質的な対策とはなり得ない。As a measure for preventing the positional change of the shield yoke 30, it is conceivable to eliminate the use of the elastic spacer 40 and to fix the shield yoke 30 in the housing 50 by shrink fitting, for example. With such a structure, the position variation of the shield yoke 30 can be prevented, but the shield yoke 30 has a tightening structure.
Since internal stress is generated in the magnetic field and changes the magnetic shield function of the shield yoke 30 and the effect as a magnetic path, the torque detection characteristic is unavoidably deteriorated and cannot be an essential countermeasure.
【0009】本発明は、上記に鑑み、弾性体スペーサを
使用しつつ、ハウジング内のシールドヨーク30の固定
状態の安定性を高め、その位置変動に因るトルク検出々
力変動を可及的に少くすることを可能としたトルクセン
サを提供しようとするものである。In view of the above, the present invention enhances the stability of the fixed state of the shield yoke 30 in the housing while using the elastic spacer, and changes the torque detection force due to the position change as much as possible. An object of the present invention is to provide a torque sensor that can be reduced in number.
【0010】[0010]
【課題を解決するための手段および作用】本発明は、励
磁・検出巻線10を内包した円筒形状のシールドヨーク
30の左右両端の円周稜部に、シールドヨーク30の円
周面31に当接する円周縁部40aとその側壁面32に
当接する側壁縁部40bとからなる略L字型断面を有す
る円環形状の弾性体スペーサ40が環着され、シールド
ヨーク30は弾性体スペーサ40を介してハウジング5
0の円筒状空間内に固定され、ハウジング50の左右の
開口端部の軸受60,60を介してトルク伝達軸Sに回
転対称に取付けられる磁歪式トルクセンサにおいて、第
1の発明に係るトルクセンサは、前記弾性体スペーサ4
0の側壁縁部40bが軸方向の押圧力によりシールドヨ
ーク30の側壁面32に押付けられて弾性圧縮している
ことを特徴としている。According to the present invention, a circle that abuts the circumferential surface 31 of the shield yoke 30 at the circumferential ridges at the left and right ends of a cylindrical shield yoke 30 including the excitation / detection winding 10. An annular elastic spacer 40 having a substantially L-shaped cross section, which is composed of a peripheral edge 40a and a side wall edge 40b that abuts against the side wall surface 32 thereof, is ring-attached, and the shield yoke 30 is connected to the housing via the elastic spacer 40. 5
In a magnetostrictive torque sensor which is fixed in a cylindrical space of 0 and is rotationally symmetrically attached to the torque transmission shaft S via the bearings 60, 60 at the left and right open ends of the housing 50, the torque sensor according to the first invention. Is the elastic spacer 4
It is characterized in that the side wall edge portion 40b of 0 is pressed against the side wall surface 32 of the shield yoke 30 by an axial pressing force and elastically compressed.
【0011】本発明の第2のトルクセンサは、前記弾性
体スペーサ40の少なくとも側壁縁部40bが、非磁性
硬質材からなる層部材42との積層構造を有し、側壁縁
部40bの弾性体層は薄肉であることを特徴としてい
る。In the second torque sensor of the present invention, at least the side wall edge portion 40b of the elastic body spacer 40 has a laminated structure with the layer member 42 made of a non-magnetic hard material, and the elastic body of the side wall edge portion 40b is formed. The layers are characterized by being thin.
【0012】本発明の第3のトルクセンサは、前記弾性
体スペーサ40の少なくとも側壁縁部40bが、その外
側面に積層された非磁性硬質材からなる層部材42との
積層構造を有し、その層部材42は、弾性体層の側壁縁
部40bの内径周面に沿つて形成された屈曲部42cを
備え、屈曲部42cの端面とシールドヨークの側壁面3
1との間に狭い隙間を有することを特徴としている。A third torque sensor of the present invention has a laminated structure in which at least the side wall edge portion 40b of the elastic spacer 40 is laminated on the outer surface of the layer member 42 made of a non-magnetic hard material. The layer member 42 includes a bent portion 42c formed along the inner peripheral surface of the side wall edge portion 40b of the elastic layer, and the end surface of the bent portion 42c and the side wall surface 3 of the shield yoke.
It is characterized in that it has a narrow gap between it and 1.
【0013】本発明の第4のトルクセンサは、前記弾性
体スペーサ40が、シールドヨークの左右の円周稜部に
沿つてその円周面31と、側壁面32とにコーテイング
により形成された薄肉層であることを特徴としている。In the fourth torque sensor of the present invention, the elastic spacer 40 is a thin layer formed by coating the circumferential surface 31 and the side wall surface 32 along the left and right circumferential ridges of the shield yoke. It is characterized by being.
【0014】以下、本発明について実施例を示す図面を
参照して説明する。図1は本発明の第1のトルクセンサ
を示している。図2(a)は、そのトルクセンサの構成
に使用される弾性体スペーサの使用前の形態、同図
(b)は、その弾性体スペーサがシールドヨーク30の
左右両端に取付けられてハウジング内に組込まれ弾性圧
縮状態を示している。励磁・検出巻線10を内包したシ
ールドヨーク30は、左右両端の円周稜部に弾性体スペ
ーサ40,40が環着されてハウジング50の円筒状空
間内に装入され、一方のスペーサ40の側壁縁部40b
はハウジング50の内周円環突起51に押圧され、他方
のスペーサ40の側壁縁部40bには当て板リング52
が押圧されている。そのスペーサ40,40の形状・構
造は、図2(a)に示すように従来より使用されている
ものと特に異ならず、その材質、肉厚等も従来のスペー
サのそれと同様のものである。The present invention will be described below with reference to the drawings showing embodiments. FIG. 1 shows a first torque sensor of the present invention. FIG. 2 (a) is a state before use of the elastic body spacer used for the construction of the torque sensor, and FIG. 2 (b) is a view showing the elastic body spacer being attached to the left and right ends of the shield yoke 30 in the housing. It shows a state of being incorporated and elastically compressed. In the shield yoke 30 including the excitation / detection winding 10, elastic spacers 40, 40 are annularly attached to the circumferential ridges at the left and right ends, and are inserted into the cylindrical space of the housing 50. Part 40b
Is pressed by the inner circumferential ring projection 51 of the housing 50, and the side plate edge portion 40 b of the other spacer 40 is attached to the contact plate ring 52.
Is being pressed. The shape and structure of the spacers 40, 40 are not particularly different from those conventionally used as shown in FIG. 2 (a), and the material and thickness thereof are the same as those of the conventional spacers.
【0015】上記のように本発明の第1のトルクセンサ
では、シールドヨーク30に従来と同様の弾性体スペー
サ40,40が環着され、またハウジング50内におけ
るシールドヨーク30は、スペーサ40,40の円周縁
部40a,40aをハウジング50の内周面に対する着
地面としてハウジング50の筒状空間内に保持されてい
る点については、前記図9に示した従来のトルクセンサ
におけるシールドヨーク30の固定態様と異ならない
が、従来の構造では、左右のスペーサ40,40の側壁
縁部40b,40bに対する押圧力の付与はなく、むし
ろ微小の空隙G(寸法精度にもよるが、約0.1〜0.
3mm程度)を伴つているのが一般であり、これと異な
つて本発明では、図2(b)に示したように、左右のス
ペーサ40,40の側壁縁部40b,40bを軸方向の
押圧力で弾性圧縮した状態のもとにシールドヨーク30
を左右から挟持させた構造としている。As described above, in the first torque sensor of the present invention, the same elastic spacers 40, 40 as the conventional one are annularly attached to the shield yoke 30, and the shield yoke 30 in the housing 50 has the spacers 40, 40. Regarding the point that the circular peripheral edge portions 40a, 40a are held in the cylindrical space of the housing 50 as the grounding surface for the inner peripheral surface of the housing 50, the shield yoke 30 in the conventional torque sensor shown in FIG. 9 is fixed. Although not different from the aspect, in the conventional structure, the pressing force is not applied to the side wall edge portions 40b, 40b of the left and right spacers 40, 40, but rather the minute gap G (depending on the dimensional accuracy, about 0.1 to about 0.1). 0.
However, in the present invention, as shown in FIG. 2B, the side wall edge portions 40b, 40b of the left and right spacers 40, 40 are pushed in the axial direction. Shield yoke 30 under the condition that it is elastically compressed by pressure
It has a structure that is sandwiched from the left and right.
【0016】このように、シールドヨーク30の両端の
スペーサ40,40の側壁縁部40b,40bをシール
ドヨーク30の側壁面32,32に押圧して弾性圧縮し
その弾性力(弾性変形量)を減じた状態でシールドヨー
ク30を挟持しているので、シールドヨーク30は、軸
体Sの回転およびその起動・停止等に伴う振動や衝撃が
繰返し作用しても、軸体Sに対する軸方向の位置ずれ
や、軸心の傾き等の位置変動を生じにくく、所定の位置
に安定に保持される。In this way, the side wall edge portions 40b, 40b of the spacers 40, 40 at both ends of the shield yoke 30 are pressed against the side wall surfaces 32, 32 of the shield yoke 30 and elastically compressed, and the elastic force (elastic deformation amount) is obtained. Since the shield yoke 30 is sandwiched in the reduced state, the shield yoke 30 is positioned in the axial direction with respect to the shaft body S even if vibrations and shocks due to the rotation of the shaft body S and its start / stop are repeatedly applied. Positional deviation such as displacement and inclination of the shaft center is unlikely to occur, and it is stably held at a predetermined position.
【0017】上記スペーサ40,40の側壁縁部40
b,40bの弾性圧縮状態の肉厚cは、例えば圧縮前の
肉厚tの約1/2〜1/4であるが、その弾性圧縮の度
合いは弾性体の材質やトルク検出における検出々力変動
許容値に応じて設定されることは言うまでもない。Side wall edges 40 of the spacers 40, 40
The wall thickness c of b and 40b in the elastically compressed state is, for example, about 1/2 to 1/4 of the wall thickness t before compression, but the degree of elastic compression depends on the material of the elastic body and the detected force in torque detection. It goes without saying that it is set according to the fluctuation allowable value.
【0018】図3は、本発明の第2のトルクセンサの構
成に使用される弾性体スペーサ40を示している。41
は弾性体層、42は、断面略L字型の非磁性硬質層部材
である。そのスペーサ40は、弾性体の肉厚の一部が非
磁性硬質層部材42に置き換えられ、弾性体層41と非
磁性硬質層部材42が積層一体化された二層構造を有し
ている。非磁性硬質層部材42は、ステンレス鋼、アル
ミ等の金属、あるいは硬度が高くかつ熱膨張係数の小さ
い樹脂(例えばガラス繊維を含むナイロン66樹脂)等
からなる成形品である。弾性体層41は、図2のスペー
サと同じようにゴム、樹脂等であるが、図2の単層スペ
ーサと異なつて、その肉厚の一部が非磁性硬質層部材4
2で置き換えられている分だけ、薄肉となつている。FIG. 3 shows an elastic spacer 40 used in the construction of the second torque sensor of the present invention. 41
Is an elastic layer, and 42 is a non-magnetic hard layer member having a substantially L-shaped cross section. The spacer 40 has a two-layer structure in which a part of the thickness of the elastic body is replaced by the non-magnetic hard layer member 42, and the elastic layer 41 and the non-magnetic hard layer member 42 are laminated and integrated. The nonmagnetic hard layer member 42 is a molded product made of a metal such as stainless steel or aluminum, or a resin having a high hardness and a small thermal expansion coefficient (for example, nylon 66 resin containing glass fiber). The elastic layer 41 is made of rubber, resin or the like like the spacer shown in FIG. 2, but unlike the single layer spacer shown in FIG.
It is thinner because it is replaced by 2.
【0019】スペーサ40の弾性体層41を非磁性硬質
層部材42との積層体としているのは、薄肉厚の弾性体
のみの単層スペーサでは、そのハンドリング性、特にシ
ールドヨーク30に対する装着操作に困難をきたすの
で、非磁性硬質層部材42と一体化して、ハンドリング
上の困難を解消しているのである。その層部材42の肉
厚は、スペーサのハンドリング性の観点から決めればよ
く、例えば0.5〜1mmとしてよい。The elastic layer 41 of the spacer 40 is laminated with the non-magnetic hard layer member 42 in the case of a single-layer spacer having only a thin elastic body for its handleability, especially for mounting operation on the shield yoke 30. Since it causes difficulty, it is integrated with the non-magnetic hard layer member 42 to solve the handling difficulty. The thickness of the layer member 42 may be determined from the viewpoint of handleability of the spacer, and may be, for example, 0.5 to 1 mm.
【0020】弾性体層41と非磁性硬質層部材42から
なる上記図3の積層スペーサ40における非磁性硬質層
部材42は、必ずしも同図に示したような断面L字型で
ある必要はなく、図4に示すように、その層部材42と
して平板形状のものを使用し側壁縁部のみを二層構造と
することにより、弾性体層41の側壁縁部41bを薄肉
化した構成としてもよい。The non-magnetic hard layer member 42 in the laminated spacer 40 of FIG. 3 consisting of the elastic body layer 41 and the non-magnetic hard layer member 42 need not necessarily have an L-shaped cross section as shown in FIG. As shown in FIG. 4, a flat plate-shaped member is used as the layer member 42, and only the side wall edge portion has a two-layer structure, so that the side wall edge portion 41b of the elastic layer 41 may be thinned.
【0021】図5は、第2のトルクセンサに使用される
積層スペーサの他の例を示している。前記図3の積層ス
ペーサでは、弾性体層41の外側面に非磁性硬質層部材
42を積層した構造としているのに対し、図5では、非
磁性硬質層部材42を弾性体層41に内包させた埋込み
構造としている点で図3の例と異なつているが、その他
の構成は同じであり、弾性体の肉厚の一部が非磁性硬質
層部材42で置き換えられている分だけ、弾性体層41
は薄肉となつている。なお、図5のスペーサについて
も、弾性体層41に内包される非磁性硬質層部材42
は、必ずしも断面L字型である必要はなく、前記図4に
示したスペーサにおける非磁性硬質層部材42と同様の
平板形状のものを使用し、これを弾性体層41の側壁縁
部41b内に埋込んだ形態としてもよい。FIG. 5 shows another example of the laminated spacer used in the second torque sensor. 3 has a structure in which the non-magnetic hard layer member 42 is laminated on the outer surface of the elastic layer 41, the non-magnetic hard layer member 42 is included in the elastic layer 41 in FIG. 3 is different from the example of FIG. 3 in that it has an embedded structure, but other configurations are the same, and the elastic body is replaced by the nonmagnetic hard layer member 42 because a part of the thickness of the elastic body is replaced. Layer 41
Is thin. The spacer of FIG. 5 also includes the non-magnetic hard layer member 42 included in the elastic layer 41.
Is not necessarily L-shaped in cross section, and a flat plate-shaped member similar to the non-magnetic hard layer member 42 in the spacer shown in FIG. 4 is used, and this is used in the side wall edge portion 41b of the elastic layer 41. It may be embedded in the form.
【0022】上記図3〜図5に示した弾性体層41と非
磁性硬質層部材42とからなる積層スペーサ40は、前
記図1のトルクセンサと同じように、シールドヨーク3
0の両端の円周稜部に環着され、そのシールドヨーク3
0は、ハウジング50内において、その左右両側からハ
ウジングの内周円環突起51と、当て板リング52との
間に挟まれて固定される。この積層スペーサ40,40
を用いてハウジング50内に固定されたシールドヨーク
30は、弾性体層41,41の側壁縁部41b,41b
の肉厚が薄く、弾性力(弾性変形量)の小さい形態を有
しているので、軸体Sの回転運動およびその起動・停止
に伴う振動や衝撃による位置変動を生じにくく、所定の
位置に安定に保持される。その弾性体層41の側壁縁部
41bの肉厚c(図5の例では非磁性硬質層部材42の
両側の肉厚c1 とc2 の合計)は、弾性体の材質やトル
ク検出での出力変動許容値等に応じて設定されるが、例
えば1mm以下の肉厚が与えられる。なお、弾性体層4
1の円周縁部41aは側壁縁部41bと異なり、敢て薄
肉とする必要はなく、従来と同様の肉厚としてよく、あ
るいは材料節減のため、例えば0.5〜1mmの薄肉と
してもよい。The laminated spacer 40 composed of the elastic body layer 41 and the non-magnetic hard layer member 42 shown in FIGS. 3 to 5 is similar to the torque sensor shown in FIG.
It is attached to the circumferential ridges at both ends of 0 and its shield yoke 3
No. 0 is fixed in the housing 50 by being sandwiched between the inner peripheral annular projection 51 of the housing and the abutment plate ring 52 from both left and right sides thereof. This laminated spacer 40, 40
The shield yoke 30 fixed in the housing 50 by using the side wall edge portions 41b, 41b of the elastic body layers 41, 41.
Has a thin wall and a small elastic force (amount of elastic deformation), it is difficult for the rotational movement of the shaft S and its position variation due to vibration or impact due to its start / stop to occur, so that the predetermined position is maintained. Holds stable. The thickness c of the side wall edge portion 41b of the elastic layer 41 (the total thickness c 1 and c 2 on both sides of the non-magnetic hard layer member 42 in the example of FIG. 5) depends on the material of the elastic body and torque detection. The thickness is set according to the output fluctuation allowable value and the like. The elastic layer 4
Unlike the side wall edge portion 41b, the circular edge portion 41a of No. 1 does not need to be made thin, and may have the same thickness as the conventional one, or may have a thin thickness of, for example, 0.5 to 1 mm in order to save material.
【0023】図6は、本発明の第3のトルクセンサの構
成に使用される弾性体スペーサの例を示している。この
弾性体スペーサ40は、弾性体層41とこれに積層され
た非磁性硬質層部材42とからなる二層構造を有し、そ
の構造は、前記図3や図4等に示した第2のトルクセン
サに使用される弾性体スペーサ40と同じであるが、そ
の非磁性硬質層部材42の側壁縁部42bの端部に、内
側方向に向う屈曲部42cが形成された形態を有してい
る点、およびその弾性体層41の側壁縁部41bは必ず
しも薄肉である必要はなく、例えば図2の弾性体スペー
サと同様の肉厚であつて構わない点において、図3や図
4に示した弾性体スペーサと異なる形態を有している。FIG. 6 shows an example of an elastic spacer used in the construction of the third torque sensor of the present invention. The elastic spacer 40 has a two-layer structure including an elastic layer 41 and a non-magnetic hard layer member 42 laminated on the elastic layer 41, and the structure is the second layer structure shown in FIGS. This is the same as the elastic spacer 40 used in the torque sensor, but has a form in which a bent portion 42c facing inward is formed at the end of the side wall edge 42b of the non-magnetic hard layer member 42. 3 and 4 in that the point and the side wall edge portion 41b of the elastic body layer 41 do not necessarily have to be thin, and may have the same thickness as the elastic body spacer of FIG. 2, for example. It has a different form from the elastic spacer.
【0024】上記非磁性硬質層部材42の屈曲部42c
は、弾性体層41の側壁縁部41bの内径周面に沿つて
シールドヨーク30の側壁面32に向つて屈曲してい
る。その屈曲部42cの前端面は、弾性体層41の側壁
縁部41bの肉厚よりも小さい隙間cをもつてシールド
ヨークの側壁面32と向い合つている。Bent portion 42c of the non-magnetic hard layer member 42
Is bent toward the side wall surface 32 of the shield yoke 30 along the inner peripheral surface of the side wall edge portion 41b of the elastic layer 41. The front end surface of the bent portion 42c faces the side wall surface 32 of the shield yoke with a gap c smaller than the wall thickness of the side wall edge portion 41b of the elastic layer 41.
【0025】図6に示した弾性体スペーサ40の弾性体
層41に積層される非磁性硬質層部材42は、必ずしも
断面L字型である必要はなく、その円周縁部42aを省
略した形状としても構わない。図7はその例を示してい
る。この場合も、非磁性硬質層部材42の屈曲部42c
は、弾性体層の側壁縁部41bの肉厚より小さい隙間c
をなしてシールヨークの側壁面32に対向している。The non-magnetic hard layer member 42 laminated on the elastic body layer 41 of the elastic body spacer 40 shown in FIG. 6 does not necessarily have to be L-shaped in cross section, and the circular peripheral edge portion 42a is omitted. I don't care. FIG. 7 shows an example thereof. Also in this case, the bent portion 42c of the non-magnetic hard layer member 42
Is a clearance c smaller than the wall thickness of the side wall edge portion 41b of the elastic layer.
And faces the side wall surface 32 of the seal yoke.
【0026】上記図6および図7の積層スペーサ40
は、図3等に示したスペーサ40と同じように、シール
ドヨーク30の両端の円周稜部に環着され、そのシール
ドヨーク30は、ハウジング50内において、その左右
両側からハウジングの内周円環突起51と、当て板リン
グ52との間に挟まれて固定される。この場合も図2の
スペーサ40と異なつて弾性体層41の側壁縁部41b
に弾性圧縮を付加する必要はない。そのシールドヨーク
30の左右のスペーサ40,40の非磁性硬質層部材4
2,42の屈曲部42c,42cは、シールドヨーク3
0の軸方向の位置ずれを抑制するストツパの役目をな
す。すなわち、軸体Sの回転およびその起動・停止に伴
う振動や衝撃が加わつても、スペーサの弾性体層41の
弾性圧縮に伴うシールドヨーク30の軸方向の変位は、
弾性体層41の肉厚の大小に関係なく、側壁面32と屈
曲部42cの隙間cの範囲内に制限され、それ以上の位
置変動を生じることはない。非磁性硬質層部材の屈曲部
42cとシールドヨークの側壁面32との間の隙間cの
大きさは、弾性体層41の材質やトルク検出の出力変動
許容値等により異なるが、例えば0.5mmないしそれ
以下に設定される。The laminated spacer 40 shown in FIGS. 6 and 7 above.
Like the spacer 40 shown in FIG. 3 and the like, the shield yoke 30 is annularly attached to the circumferential ridges at both ends of the shield yoke 30. It is sandwiched and fixed between 51 and the pad plate ring 52. Also in this case, unlike the spacer 40 of FIG. 2, the side wall edge portion 41b of the elastic layer 41 is
It is not necessary to add elastic compression to. The non-magnetic hard layer member 4 of the left and right spacers 40, 40 of the shield yoke 30.
The bent portions 42c and 42c of the reference numerals 2 and 42 are used for the shield yoke 3
It plays the role of a stopper that suppresses the displacement of 0 in the axial direction. That is, even if vibration or shock is applied due to the rotation of the shaft S and its start / stop, the axial displacement of the shield yoke 30 due to the elastic compression of the elastic layer 41 of the spacer is
Regardless of the thickness of the elastic body layer 41, it is limited within the range of the gap c between the side wall surface 32 and the bent portion 42c, and no further positional fluctuation occurs. The size of the gap c between the bent portion 42c of the non-magnetic hard layer member and the side wall surface 32 of the shield yoke varies depending on the material of the elastic layer 41, the torque detection output fluctuation allowable value, etc., but is, for example, 0.5 mm. Or set to less than that.
【0027】図8は、本発明の第4のトルクセンサを構
成する弾性体スペーサの形設態様を示している。その弾
性体スペーサ40は、シールドヨーク30の左右両端の
円周稜部に、シールドヨークの外周面31と側壁面32
を被覆する断面略L字形状を有する薄肉のコーテイング
層として形設されている。コーテイングスペーサ40が
形設されたシールドヨーク30は、ハウジング50内に
装入されて、左右のスペーサ40,40のそれぞれに当
接するハウジング50の内周円環突起51および当て板
リング52に挟まれて固定される。この場合も、前記図
2のトルクセンサと異なつてスペーサ40,40の側壁
縁部40b,40bは押圧力による弾性圧縮を付加する
必要はなく、前記図3や図4の積層スペーサを使用した
固定構造と同じように、スペーサの側壁縁部40b,4
0bが、弾性力(弾性変形量)の小さい薄肉形態である
ことの効果として、シールドヨーク30は、軸体Sの回
転運動およびその起動・停止に伴う振動や衝撃による位
置変動を生じにくく、所定の位置に安定に保持される。
そのスペーサ40の側壁縁部40bの肉厚cは、弾性体
の材質やトルク検出での出力変動許容値等により設定さ
れるが、例えば1mmないしそれ以下とされる。FIG. 8 shows the shape of the elastic spacers that form the fourth torque sensor of the present invention. The elastic spacers 40 are provided on the outer peripheral surface 31 and the side wall surface 32 of the shield yoke at the circumferential ridges at the left and right ends of the shield yoke 30.
Is formed as a thin coating layer having a substantially L-shaped cross section. The shield yoke 30 in which the coating spacer 40 is formed is inserted into the housing 50, and is sandwiched by the inner peripheral annular projection 51 and the abutment plate ring 52 of the housing 50 that come into contact with the left and right spacers 40, 40. Fixed. Also in this case, unlike the torque sensor of FIG. 2, the side wall edge portions 40b, 40b of the spacers 40, 40 do not need to be elastically compressed by the pressing force, and fixed using the laminated spacers of FIGS. 3 and 4. Similar to the structure, the spacer sidewall edges 40b, 4
0b has a small elastic force (elastic deformation amount), and as a result, the shield yoke 30 is less likely to undergo positional fluctuation due to vibration or impact accompanying the rotational movement of the shaft S and its start / stop, and thus the shield yoke 30 has a predetermined shape. It is stably held in the position.
The thickness c of the side wall edge portion 40b of the spacer 40 is set depending on the material of the elastic body, the output fluctuation allowable value in torque detection, and the like, and is set to, for example, 1 mm or less.
【0028】[0028]
【発明の効果】本発明の磁歪式トルクセンサは、励磁・
検出巻線を内包したシールドヨークのハウジング内にお
ける固定姿勢が安定で、トルク伝達軸の回転およびその
起動・停止に伴う振動や衝撃による軸方向の位置ずれや
軸心の傾き等の位置変動を生じにくゝ、従つてシールド
ヨークの位置変動に因るトルク検出々力の変動量が少な
く、精度の良いトルク検出を行うことができる。According to the magnetostrictive torque sensor of the present invention,
The shield yoke containing the detection winding has a stable fixed posture inside the housing, and vibrations and shocks associated with the rotation and start / stop of the torque transmission shaft cause axial displacement and positional fluctuations such as axial tilt. Therefore, the fluctuation amount of torque detection force due to the position fluctuation of the shield yoke is small, and accurate torque detection can be performed.
【図1】本発明のシールドヨーク固定構造の実施例を示
す軸方向断面図である。FIG. 1 is an axial sectional view showing an embodiment of a shield yoke fixing structure of the present invention.
【図2】同図aは、図1のトルクセンサに使用される弾
性体スペーサを示す軸方向断面図、同図bは、図1のハ
ウジング内における弾性体スペーサの弾性圧縮状態を示
す要部拡大図である。2A is an axial cross-sectional view showing an elastic spacer used in the torque sensor of FIG. 1, and FIG. 2B is a main part showing an elastic compression state of the elastic spacer in the housing of FIG. FIG.
【図3】本発明におけるシールドヨークに取付けられる
スペーサの実施例を示す径方向断面図である。FIG. 3 is a radial cross-sectional view showing an embodiment of a spacer attached to the shield yoke in the present invention.
【図4】本発明におけるシールドヨークに取付けられる
スペーサの実施例を示す径方向断面図である。FIG. 4 is a radial cross-sectional view showing an embodiment of a spacer attached to the shield yoke in the present invention.
【図5】本発明におけるシールドヨークに取付けられる
スペーサの実施例を示す径方向断面図である。FIG. 5 is a radial cross-sectional view showing an embodiment of a spacer attached to the shield yoke in the present invention.
【図6】本発明におけるシールドヨークに取付けられる
スペーサの実施例を示す径方向断面図である。FIG. 6 is a radial cross-sectional view showing an embodiment of a spacer attached to the shield yoke in the present invention.
【図7】本発明におけるシールドヨークに取付けられる
スペーサの実施例を示す径方向断面図である。FIG. 7 is a radial cross-sectional view showing an embodiment of a spacer attached to the shield yoke in the present invention.
【図8】本発明におけるシールドヨークに形設されたス
ペーサを示す一部切欠要部正面図である。FIG. 8 is a partially cutaway front view showing a spacer formed in a shield yoke according to the present invention.
【図9】従来のシールドヨーク固定構造を示す軸方向断
面図である。FIG. 9 is an axial sectional view showing a conventional shield yoke fixing structure.
【図10】トルクセンサの分解説明図である。FIG. 10 is an exploded view of the torque sensor.
10:励磁・検出巻線,20:ボビン,30:シールド
ヨーク,40:スペーサ,40a:円周縁部,40b:
側壁縁部,41:弾性体層,42:非磁性硬質層部材,
50:ハウジング,51:ハウジング内周円環突起,5
2:当て板リング,60:軸受。10: excitation / detection winding, 20: bobbin, 30: shield yoke, 40: spacer, 40a: circular edge portion, 40b:
Side wall edge portion, 41: elastic layer, 42: non-magnetic hard layer member,
50: housing, 51: housing inner circumference annular projection, 5
2: patch plate ring, 60: bearing.
Claims (4)
のシールドヨーク30の左右両端の円周稜部に、シール
ドヨーク30の円周面31に当接する円周縁部40aと
その側壁面32に当接する側壁縁部40bとからなる略
L字型断面を有する円環形状の弾性体スペーサ40が環
着され、シールドヨーク30は弾性体スペーサ40を介
してハウジング50の円筒状空間内に固定され、ハウジ
ング50の左右の開口端部の軸受60,60を介してト
ルク伝達軸Sに回転対称に取付けられる磁歪式トルクセ
ンサにおいて、 前記弾性体スペーサ40は、その側壁縁部40bが、軸
方向の押圧力により弾性圧縮してシールドヨーク30の
側壁面32に押付けられていることを特徴とする磁歪式
トルクセンサ。1. A cylindrical shield yoke 30 including an excitation / detection winding 10 is provided at its circumferential ridges at both left and right ends with a circumferential edge portion 40a abutting a circumferential surface 31 of the shield yoke 30 and a side wall surface 32 thereof. A ring-shaped elastic spacer 40 having a substantially L-shaped cross section composed of the side wall edges 40b in contact with each other is annularly attached, and the shield yoke 30 is fixed in the cylindrical space of the housing 50 via the elastic spacer 40. In the magnetostrictive torque sensor mounted rotationally symmetrically on the torque transmission shaft S via the bearings 60, 60 at the left and right opening ends of the housing 50, the side wall edge portion 40b of the elastic body spacer 40 pushes in the axial direction. A magnetostrictive torque sensor, which is elastically compressed by pressure and pressed against the side wall surface 32 of the shield yoke 30.
のシールドヨーク30の左右両端の円周稜部に、シール
ドヨーク30の円周面31に当接する円周縁部40aと
その側壁面32に当接する側壁縁部40bとからなる略
L字型断面を有する円環形状の弾性体スペーサ40が環
着され、シールドヨーク30は弾性体スペーサ40を介
してハウジング50の円筒状空間内に固定され、ハウジ
ング50の左右の開口端部の軸受60,60を介してト
ルク伝達軸Sに回転対称に取付けられる磁歪式トルクセ
ンサにおいて、 前記弾性体スペーサ40は、少なくとも側壁縁部40b
が非磁性硬質材からなる層部材42との積層構造を有
し、側壁縁部40bの弾性体層は薄肉であることを特徴
とする磁歪式トルクセンサ。2. A cylindrical peripheral edge portion 40a which abuts on a circumferential surface 31 of the shield yoke 30 and a side wall surface 32 thereof are attached to the circumferential ridge portions at the left and right ends of the cylindrical shield yoke 30 including the excitation / detection winding 10. A ring-shaped elastic spacer 40 having a substantially L-shaped cross section composed of the side wall edges 40b in contact with each other is annularly attached, and the shield yoke 30 is fixed in the cylindrical space of the housing 50 via the elastic spacer 40. In the magnetostrictive torque sensor mounted rotationally symmetrically on the torque transmission shaft S via the bearings 60, 60 at the left and right open ends of the housing 50, the elastic spacer 40 includes at least the side wall edge portion 40b.
Has a laminated structure with the layer member 42 made of a non-magnetic hard material, and the elastic layer of the side wall edge portion 40b is thin.
のシールドヨーク30の左右両端の円周稜部に、シール
ドヨーク30の円周面31に当接する円周縁部40aと
その側壁面32に当接する側壁縁部40bとからなる略
L字型断面を有する円環形状の弾性体スペーサ40が環
着され、シールドヨーク30は弾性体スペーサ40を介
してハウジング50の円筒状空間内に固定され、ハウジ
ング50の左右の開口端部の軸受60,60を介してト
ルク伝達軸Sに回転対称に取付けられる磁歪式トルクセ
ンサにおいて、 前記弾性体スペーサ40は、少なくとも側壁縁部40b
が、その外側面に積層された非磁性硬質材からなる層部
材42との積層構造を有し、その層部材42は、弾性体
層の側壁縁部41bの内径周面に沿つて形成された屈曲
部42cを備え、屈曲部42cの端面とシールドヨーク
の側壁面32との間に狭い隙間を有することを特徴とす
る磁歪式トルクセンサ。3. A cylindrical peripheral edge portion 40a which abuts on a circumferential surface 31 of the shield yoke 30 and a side wall surface 32 of the cylindrical shield yoke 30 which encloses the excitation / detection winding 10 at the left and right ends thereof. A ring-shaped elastic spacer 40 having a substantially L-shaped cross section composed of the side wall edges 40b in contact with each other is annularly attached, and the shield yoke 30 is fixed in the cylindrical space of the housing 50 via the elastic spacer 40. In the magnetostrictive torque sensor mounted rotationally symmetrically on the torque transmission shaft S via the bearings 60, 60 at the left and right open ends of the housing 50, the elastic spacer 40 includes at least the side wall edge portion 40b.
Has a laminated structure with a layer member 42 made of a non-magnetic hard material laminated on the outer surface thereof, and the layer member 42 is formed along the inner peripheral surface of the side wall edge portion 41b of the elastic layer. A magnetostrictive torque sensor comprising a bent portion 42c and having a narrow gap between the end surface of the bent portion 42c and the side wall surface 32 of the shield yoke.
のシールドヨーク30の左右両端の円周稜部に、シール
ドヨーク30の円周面31に当接する円周縁部40aと
その側壁面32に当接する側壁縁部40bとからなる略
L字型断面を有する円環形状の弾性体スペーサ40が形
設され、シールドヨーク30は弾性体スペーサ40を介
してハウジング50の円筒状空間内に固定され、ハウジ
ング50の左右の開口端部の軸受60,60を介してト
ルク伝達軸Sに回転対称に取付けられる磁歪式トルクセ
ンサにおいて、 前記弾性体スペーサ40は、シールドヨーク30の左右
の円周稜部にそつて、その円周面31と側壁面32とに
コーテイングにより形成された薄肉層であることを特徴
とする磁歪式トルクセンサ。4. A cylindrical shield yoke 30 including the excitation / detection winding 10 is provided at its circumferential ridges at both left and right ends with a circumferential edge portion 40a abutting a circumferential surface 31 of the shield yoke 30 and a side wall surface 32 thereof. An annular elastic spacer 40 having a substantially L-shaped cross section formed of the side wall edges 40b in contact with each other is formed, and the shield yoke 30 is fixed in the cylindrical space of the housing 50 via the elastic spacer 40. In the magnetostrictive torque sensor which is rotationally symmetrically attached to the torque transmission shaft S via the bearings 60, 60 at the left and right opening ends of the housing 50, the elastic spacer 40 is provided along the left and right circumferential ridges of the shield yoke 30. A magnetostrictive torque sensor, characterized in that the circumferential surface 31 and the side wall surface 32 are thin layers formed by coating.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3302423A JP2678843B2 (en) | 1991-10-21 | 1991-10-21 | Magnetostrictive torque sensor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3302423A JP2678843B2 (en) | 1991-10-21 | 1991-10-21 | Magnetostrictive torque sensor |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH05113377A true JPH05113377A (en) | 1993-05-07 |
JP2678843B2 JP2678843B2 (en) | 1997-11-19 |
Family
ID=17908743
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3302423A Expired - Lifetime JP2678843B2 (en) | 1991-10-21 | 1991-10-21 | Magnetostrictive torque sensor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2678843B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1464936A2 (en) * | 2003-04-02 | 2004-10-06 | HONDA MOTOR CO., Ltd. | Torque sensor |
CN103063343A (en) * | 2011-10-18 | 2013-04-24 | 姚立和 | Torsion inductor |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6078479U (en) * | 1983-10-31 | 1985-05-31 | 日本電気株式会社 | Non-slip clip |
JPS61278617A (en) * | 1985-05-31 | 1986-12-09 | Toshiba Corp | Bearing device |
JPH02128931U (en) * | 1989-03-30 | 1990-10-24 |
-
1991
- 1991-10-21 JP JP3302423A patent/JP2678843B2/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6078479U (en) * | 1983-10-31 | 1985-05-31 | 日本電気株式会社 | Non-slip clip |
JPS61278617A (en) * | 1985-05-31 | 1986-12-09 | Toshiba Corp | Bearing device |
JPH02128931U (en) * | 1989-03-30 | 1990-10-24 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1464936A2 (en) * | 2003-04-02 | 2004-10-06 | HONDA MOTOR CO., Ltd. | Torque sensor |
EP1464936B1 (en) * | 2003-04-02 | 2007-04-25 | HONDA MOTOR CO., Ltd. | Torque sensor |
CN103063343A (en) * | 2011-10-18 | 2013-04-24 | 姚立和 | Torsion inductor |
Also Published As
Publication number | Publication date |
---|---|
JP2678843B2 (en) | 1997-11-19 |
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