JP4227230B2 - Vibration wave driving device and method for manufacturing friction contact portion in vibration wave driving device - Google Patents

Description

【００２５】
（注）
（１）ＪＫ（ＪＥＴ ＫＯＴＥ）は溶射ガン名を示す。
（２）ＷＣの融点は２７００℃である。
【００２６】
次に、これらの溶射法で溶射した移動体を用いて実験を行った。
その結果、ＪＫ（ＪＥＴ ＫＯＴＥ）を使用した、ＷＣ粒の溶け込んでいる溶射面の移動体が最も良好な結果が得られた。
先ず、ＷＣ−Ｃｏを原料として、溶射燃料に灯油を使用し、ＪＰ５０００でＨＶＯＦ溶射を行った移動体では、粒が残っている為、摺動時に脱粒しそれが砥粒の様になり双方の摩擦摺動面を痛め、傷の発生が多くなった。
【００２７】
次に、プラズマ溶射を行った移動体では、溶射温度が高い為、粒が溶け込んでいるものの、温度が高過ぎる為、移動体が変形してしまい平面度が悪くなり、回転摺動時に回転ムラが起こるようになってしまった。
【００２８】
もう１種類の溶射法である、ＪＫ（ＪＥＴ ＫＯＴＥ）を使用したものでは、Ｃｏやη相のマトリックスが多くなり、ＷＣ粒の溶け込み、脱粒する事がなく、又、プラズマ溶射程溶射温度が高くない為、移動体の変形もなく傷の発生も少ない最も良い結果が得られた。
【００２９】
次に、本発明において、溶射するＷＣの粉末を作成する際、焼結粉砕又は溶融粉砕したものを使用する事について説明する。
溶射に使用するＷＣ−Ｃｏ粉末として、一般には造粒粉末か焼結粉末等が用いられている。この２種類の粉末を比べると、造粒粉末の方がＷＣの分解が少なく粒径も小さい為、耐摩耗性の観点からは優れているといわれている。又これは、造粒されている分、粒の流れ性が良くなり、溶射ガンへの溶射粉末の供給がスムーズになり、工程上、分留まりが少なくなる。又、焼結させない分、製造工程が減り、溶射粉末のコストが下がるというメリットが生じる。
【００３０】
しかし、この場合、先程と同様、振動により摺動する振動波駆動装置では、ＷＣの分解が少ない為、ＷＣ−Ｃｏ同士の溶着が弱く、脱粒しやすくなる。
そこで、ＷＣ−Ｃｏの粉末を混ぜ、それを焼結し粉砕したもの、又は溶融し粉砕したものの場合は、焼結、溶融時の熱により、すでにＷＣとＣｏが溶け合っているので溶射時に密着性が良くなる。
【００３１】
焼結粉砕又は、溶融粉砕したものとしてメテコ（株）の７１ＶＦ−ＮＳ（登録商標）を溶射したものと、造粒粉のＷＣ−Ｃｏを溶射したものとの２００Ｈｒ摩擦摺動後のＷＣ−Ｃｏ摺動面の形状測定結果の断面図を各々図５および図６に示す。図５に示すメテコ（株）の７１ＶＦ−ＮＳの場合は、焼結又は溶融する事により熱を加えられ、脱炭しＷＣとＣｏが溶けあい混ざっており、一方、図６に示す造粒粉ではＷＣの分解が少なく、ＷＣとＣｏが別れているものと考えられる。その為、造粒粉の方はかなり削られていた。
【００３２】
次に、ＷＣ−Ｃｏ溶射膜のＣｏ含有率であるが、これは通常各溶射材メーカーから市販されている９〜２５重量％のものと、３０重量％、５０重量％のものと、焼結材料である６．５重量％のもので実験を行った。上記の試料Ｎｏ．２〜５（９〜２５重量％のもの）には、Ｗ・Ｃｏ・Ｃの三元系金属間化合物（η相）が生成していた。
【００３３】
その実験条件は、回転数６０ｒｐｍ、駆動時間２００Ｈｒｓ、移動体直径７３ｍｍ、実験室温度２０℃、実験室湿度２５％であり、摩擦摺動後の結果を表２および３に示す。
【００３４】
【表２】

【００３５】
【表３】

【００３６】
（注）ＷＣ−Ｃｏ摺動面の判定
◎：摺動キズの深さ ０
○：摺動キズの深さ ０．１〜０．９μｍ
×：摺動キズの深さ １．０μｍ以上
【００３７】
表２、３の結果から、Ｃｏを１２重量％含有させたものが最も良い結果が得られたが、９〜２５重量％の範囲では相手側への顕著な摩耗増大等の影響も与えず、実用上問題の無いレベルであり、それぞれ良好な結果が得られた。それに対し、６．５、３０、５０重量％のものは、摩耗量が多く、駆動後には回転ムラの悪化と、異音の発生が見られた。
【００３８】
ＷＣにＣｏを含有させた時の効果として、ＷＣを母材に接着させる事や、ＷＣ同士を密着させるバインダーの役割が挙げられる。Ｃｏの含有量が少ない場合は、密着強度が落ち、脱粒を起こしやすくなり、その結果、それが砥粒となり、相手材の摩耗が増大し、回転ムラが生じやすくなる。反対にＣｏの含有量が多い場合は、ＷＣと比較するとＣｏは軟らかい為、溶射膜に十分な硬度が得られなくなる。その為、ＷＣ−Ｃｏの摺動面が荒れ、相手材の摩耗が増大し、回転ムラが生じる。又、ＷＣ−Ｃｏの摺動面の荒れ、相手材の摩耗増大の為、駆動中に異音を生じる。
【００３９】
次に、本発明におけるＷＣ−Ｃｏ溶射膜の摩擦接触する、もう一方の摩擦接触部には、硬質アルマイトが用いられる。
【００４０】
図７は本発明の振動波駆動装置の実施形態として振動波モータの一例を示す断面図である。図中、１は振動体でステンレス鋼からなるリング状の金属弾性体９の一端面に、前述の様にリング状で複数個に分極された２群の圧電素子４を耐熱性のエボキシ樹脂系接着剤で接着し、金属弾性体９のもう一方の端面には摩擦材５が同様に接着して形成されている。
【００４１】
一方、移動体２側のアルミニウム合金からなるリング状の接触体６の摩擦摺動面には摩擦材６ａを設けてある。接触体６はゴムリング７を介して支持体８に取付けてあり、支持体８はネジ１１により出力軸１２に固定されている。そして、振動体１の摩擦材５と接触体６の摩擦材６ａは接触して摩擦摺動面を形成し、加圧用の板バネ１６により、軸方向に例えば総圧で５ｋｇｆの荷重で加圧されている。１９はベアリング、１３はカバー、１４、１５は与圧カラー、１７はカラーでネジ１１ａにより出力軸１２に固定されている。
【００４２】
そして、交互に厚み方向に分極処理された２群の圧電素子４に振動体１に固有の周波数の交流電圧を印加すると、振動体１は共振を起こし、その周方向に進行性振動波を生じ、摩擦材５を介して摩擦材６ａに摩擦力が作用し、移動体２は回転駆動する。
【００４３】
本発明においては、上記の振動体及び移動体のうち一方の摩擦接触部が、溶射ＷＣ−Ｃｏの溶射膜により形成されており、かつ該溶射膜に溶射によりＷ・Ｃｏ・Ｃの三元系金属間化合物（η相）が生成されているので、振動モータの摩擦接触面の摩耗を抑制する事ができる。
【００４４】
上記実施例では、摩擦材を図７に示した円盤状の振動波モータに適用した例を示したが、その他に棒状の振動波モータに同様の方法で、上記の摩擦材を設けた摩擦接触面を形成してもよい。
【００４５】
また、図８は、図７に示した振動波モータを駆動源とする機器の概略図である。２３は大歯車２３ａと小歯車２３ｂを有するギアで、大歯車２３ａが振動波モータ側のギア２０と噛合している。２４は被駆動部材、例えばレンズ鏡筒で、外周部に設けられたギア２４ａにギア２３の小歯車２３ｂが噛合し、モータの駆動力により回転する。一方、ギア２３にはエンコーダスリット板２５が取り付けられ、ギア２３の回転をフォトカップラー２６により検出し、例えばオートフォーカスのためにモータの回転、停止を制御する。
【００４６】
【発明の効果】
以上説明したように、本発明によれば、振動体及び移動体のうち一方の摩擦接触部が溶射ＷＣ−Ｃｏの溶射膜により形成されており、かつ該溶射膜に溶射によりＷ・Ｃｏ・Ｃの三元系金属間化合物（η相）が生成されていること、摩擦接触面の摩耗を抑制した耐久性が高い振動波駆動装置が得られる。
【図面の簡単な説明】
【図１】本発明の振動波駆動装置の一実施形態であるリング状振動波モーターの摩擦接触部を示す概略図である。
【図２】図１の振動波駆動装置の振動体を示す説明図である。
【図３】図１の振動波駆動装置の駆動状態を示す説明図である。
【図４】本発明の溶射タングステンカーバイド−コバルト（ＷＣ−Ｃｏ）のＷ・Ｃｏ・Ｃの三元系金属間化合物（η相）の金属組織を示す電子顕微鏡写真である。
【図５】メテコ（株）の７１ＶＦ−ＮＳ（登録商標）を溶射したものの２００Ｈｒ摩擦摺動後のＷＣ−Ｃｏ摺動面を示す断面図である。
【図６】造粒粉のＷＣ−Ｃｏを溶射したものの２００Ｈｒ摩擦摺動後のＷＣ−Ｃｏ摺動面を示す断面図である。
【図７】本発明の振動波モータの一例を示す断面図である。
【図８】図７に示した振動波モータを駆動源とする機器の概略図である。
【符号の説明】
１ 振動体
１ａ 振動体側の摩擦材
ｌｂ 突起
２ 移動体
２ａ 移動体側の接触面
３ 機械−電気エネルギー変換素子
４ 圧電素子
５ 摩擦材
６ 接触体
６ａ 摩擦材
８ 支持体
９ 金属弾性体
１１，１１ａ ネジ
１２ 出力軸
１３ カバー
１４、１５ 与圧カラー
１６ 板バネ
１７ カラー
１９ ベアリング[0001]
BACKGROUND OF THE INVENTION
In the present invention, a progressive vibration wave is generated in a vibrating body by applying a voltage to the electromechanical energy conversion element, and a relative movement is caused between the moving body and the moving body in contact with the vibrating body by friction drive. The present invention relates to a vibration wave driving device and a method for manufacturing a friction contact portion in the vibration wave driving device .
[0002]
[Prior art]
In general, a vibration wave driving device excites a circular or elliptical motion on the surface particles of a vibrating body, and frictionally drives a moving body pressed by this. A friction material is attached to the vibrating body and the moving body of the vibration wave generator so that the vibration generated in the vibrating body is efficiently transmitted to the moving body. Therefore, it is desirable to provide a friction material with a large friction coefficient at the pressure contact portion of the vibrating body and the moving body in order to extract the output of the vibration wave driving device more efficiently. It leads to the durable life of the device. For example, Japanese Patent Laid-Open No. 62-100188 proposes using WC-Co for the friction contact portion and using hard alumite for the other friction contact portion.
[0003]
[Problems to be solved by the invention]
However, although WC-Co having high hardness is used for one friction contact portion, both friction contact surfaces may be worn. In general, for the thermal spraying WC-Co, a thermal spraying method in which WC grains do not melt is selected in order to maintain a high hardness. However, in a vibration wave driving device including a vibrating body that generates vibration and a moving body that is in frictional contact with the vibrating body and moves relative to the vibrating body due to the vibration, the WC particles are slid by vibration. Graining will damage both printing contact surfaces and reduce performance. WC-Co is tungsten carbide-cobalt, and WC is tungsten carbide.
[0004]
In addition, it is known that the composition of the WC-Co sprayed coating changes depending on the method of producing the sprayed powder, and generally a granulated powder or a sintered powder is used. Comparing these powders, it is said that the granulated powder is superior from the viewpoint of wear resistance because the decomposition of WC at the time of thermal spraying is small and the particle size is also small. However, as described above, in the vibration wave driving device that slides by vibration, the amount of decomposition of WC is small, so that the adhesion between WC grains is weak and easy to degranulate.
[0005]
Furthermore, since the content of Co in WC affects the hardness of WC—Co and the adhesion between WC—Co, it is necessary to contain an optimal amount of Co. Co is cobalt.
[0006]
Accordingly, an object of the present invention is to provide a vibration wave driving device with high durability in which wear of the friction contact surface is suppressed, and a method for manufacturing a friction contact portion in the vibration wave driving device .
[0007]
[Means for Solving the Problems]
That is, the present invention relates to a vibration wave driving apparatus including a vibrating body that generates vibration and a moving body that is in frictional contact with the vibrating body and moves relative to the vibrating body by vibration. among one of the frictional contact is tungsten carbide - is formed by spray coating of cobalt, and is characterized in that the solution reflection film comprises tungsten, cobalt, a ternary intermetallic compound according carbide.
[0008]
In addition, the present invention provides a vibration wave driving device including a vibrating body that generates vibration and a moving body that frictionally contacts the vibrating body and moves relative to the vibrating body by vibration. In the manufacturing method for forming one frictional contact portion, the surface of the vibrating body is thermally sprayed with tungsten carbide-cobalt to form a sprayed film containing a ternary intermetallic compound of tungsten, cobalt, and carbide. To do.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
The vibration wave driving device of the present invention includes a vibrating body that generates vibration, and a moving body that frictionally contacts the vibrating body and moves relative to the vibrating body by vibration. One frictional contact portion of the moving body is formed of a sprayed WC-Co sprayed coating, and a W / Co / C ternary intermetallic compound (η phase) is generated by spraying on the sprayed coating. It is characterized by being. C is carbide.
[0011]
In particular, in the present invention, in a vibration wave driving device including a vibrating body that generates vibration and a moving body that contacts the vibrating body, one of the vibrating contact body and the frictional contact body of the moving body is sprayed WC-Co ( Co: 9 to 25% by weight), HVOF spraying using ethylene as the thermal spray fuel and jet coat gun (registered trademark) as the thermal spray, and the sprayed film melts into a layer, W · Co · C A ternary intermetallic compound (η phase) is produced, and the sprayed WC-Co powder is sintered or melt-pulverized.
[0012]
The vibration wave driving device of the present invention can be used for, for example, a vibration wave motor, a paper feeding device, a linear motor, and the like.
Further, the vibration wave driving device of the present invention can be used for various devices as a driving source. Specific examples of equipment include optical equipment such as cameras, office equipment such as printers and copiers, and automobile-related equipment such as power windows and active suspensions.
[0013]
【Example】
The present invention will be specifically described below with reference to examples.
FIG. 1 is a schematic diagram showing a frictional contact portion of a ring-shaped vibration wave motor which is an embodiment of the vibration wave drive device of the present invention. 2 is an explanatory diagram showing a vibrating body of the vibration wave driving device of FIG. 1, and FIG. 3 is an explanatory diagram showing a driving state of the vibration wave driving device of FIG. The driving principle of the vibration wave motor shown in FIGS. 1 to 3 is already known, for example, from Japanese Patent Application Laid-Open No. 59-201685.
[0014]
In the figure, reference numeral 1 denotes a vibrating body. The vibrating body 1 is formed in a ring shape having a diameter of 73 mm, and a large number of protrusions 1b are formed in the circumferential direction of the upper surface. A friction material la is provided on each protrusion 1b. The friction material la is hard anodized.
[0015]
Reference numeral 2 denotes a moving body, and WC-Co is thermally sprayed on the friction material 2 a at the contact portion of the moving body 2. The sprayed surface is processed by applying a pressure of 1 MPa to a grinder using a resin # 2000 diamond grindstone so that the center line roughness (Ra) is 0.03 μmRa.
[0016]
Reference numeral 3 denotes an electromechanical energy conversion element joined to the vibrating body 1. The converting element 3 receives an alternating voltage and generates a progressive vibration wave on the protrusion 1 b of the vibrating body 1. As a result, the moving body 2 rotates, but this movement is a relative one caused by frictional force. If the vibrating body 1 is fixed, the moving body 2 rotates.
[0017]
Therefore, an experiment was conducted using the moving body 2 sprayed by several types of spraying methods.
Usually, it is said that the thermal sprayed WC-Co is preferably in a state in which hard WC grains are not melted, and the one in which WC grains remain is used.
[0018]
For example, when HVOF (High Velocity Oxygen-Fuel Flame Spraying) spraying is performed using WC-Co as a raw material, kerosene as the thermal spray fuel, and JP5000 (registered trademark) as the thermal spray gun, in this case, thermal spraying is performed at a low temperature. Therefore, it is possible to maintain the high hardness without dissolving the WC grains.
[0019]
However, in a vibration wave driving device including a vibrating body that generates vibration and a moving body that is in frictional contact with the vibrating body and moves relative to the vibrating body by the vibration, the vibration wave driving device is slid due to vibration. The WC particles in the matrix are shattered, damaging both frictional sliding surfaces and lowering the performance.
[0020]
Therefore, as a thermal spraying method for melting WC grains, there is plasma spraying. However, this spraying temperature is very high and the WC grains are sufficiently melted. However, since the temperature is too high, the base material is affected and the moving body is affected. It may be deformed.
[0021]
Next, there is HVOF spraying using WC-Co as a raw material and low spraying temperature, using ethylene as the spraying fuel and using a jet coat gun (registered trademark) as the spraying. A sprayed surface on which a large amount of Co / C ternary intermetallic compound (η phase) is generated.
[0022]
FIG. 4 is an electron micrograph showing an example of a metal structure (molten structure) of a ternary intermetallic compound of W, Co, and C. In the figure, A indicates a sprayed film, B indicates a base material made of aluminum, and C indicates nothing. The white part of the molten structure indicates the ternary intermetallic compound (η phase).
[0023]
Further, there is a difference in the spraying temperature by the spray gun, for example, as shown in Table 1 below.
[0024]
[Table 1]

[0025]
(note)
(1) JK (JET KOTE) indicates a spray gun name.
(2) The melting point of WC is 2700 ° C.
[0026]
Next, experiments were performed using the moving body sprayed by these spraying methods.
As a result, the best result was obtained with the moving body of the sprayed surface in which WC grains were dissolved, using JK (JET KOTE) .
Both First, the WC-Co was used as a raw material, the kerosene in spraying fuel, in the moving body was HVOF spraying in JP500 0, because there remains a grain, and shedding at the time of sliding it to be as abrasive grains The friction sliding surface was damaged, and the number of scratches increased.
[0027]
Next, in the moving body that has been plasma sprayed, since the spraying temperature is high, the particles are melted, but because the temperature is too high, the moving body is deformed and the flatness is deteriorated. Has come to happen.
[0028]
Another type of spraying method, using JK (JET KOTE) , increases the matrix of Co and η phases, prevents WC grains from melting and degranulating, and the plasma spraying temperature is high. Therefore, the best results were obtained with no deformation of the moving body and few scratches.
[0029]
Next, in the present invention, description will be made on the use of sintered or melt-pulverized WC powder when creating a thermal sprayed WC powder.
Generally, granulated powder or sintered powder is used as the WC-Co powder used for thermal spraying. Comparing these two types of powders, the granulated powder is said to be superior from the viewpoint of wear resistance because it has less WC decomposition and smaller particle size. In addition, the flowability of the grains is improved by the amount of granulation, the sprayed powder is smoothly supplied to the spray gun, and the yield is reduced in the process. In addition, there is a merit that the manufacturing process is reduced and the cost of the thermal spray powder is reduced by the amount not sintered.
[0030]
However, in this case, as in the previous case, in the vibration wave drive device that slides by vibration, since the decomposition of WC is small, the welding of WC-Co is weak and the particles are easily separated.
Therefore, in the case of WC-Co powder mixed, sintered and pulverized, or melted and pulverized, WC and Co are already melted by heat during sintering and melting, so adhesion during thermal spraying Will be better.
[0031]
WC-Co after 200Hr friction sliding between the sprayed MET-Co., Ltd. 71VF-NS (registered trademark) and the sprayed WC-Co granulated powder as sintered or melt-pulverized Cross-sectional views of the sliding surface shape measurement results are shown in FIGS. 5 and 6, respectively. In the case of 71VF-NS of Metco Co., Ltd. shown in FIG. 5, heat is applied by sintering or melting, decarburization and WC and Co are melted and mixed, while the granulated powder shown in FIG. Therefore, it is considered that the decomposition of WC is small and WC and Co are separated. For this reason, the granulated powder was considerably shaved.
[0032]
Next, the Co content of the WC-Co sprayed film, which is usually 9-25% by weight, 30% by weight, 50% by weight, and sintered The experiment was conducted with 6.5% by weight of the material. In the above sample No. In 2 to 5 (9 to 25% by weight), W · Co · C ternary intermetallic compound (η phase) was formed.
[0033]
The experimental conditions were a rotational speed of 60 rpm, a driving time of 200 Hrs, a moving body diameter of 73 mm, a laboratory temperature of 20 ° C., a laboratory humidity of 25%, and the results after friction sliding are shown in Tables 2 and 3.
[0034]
[Table 2]

[0035]
[Table 3]

[0036]
(Note) Judgment of WC-Co sliding surface A: Depth of sliding scratch 0
○: Sliding scratch depth 0.1-0.9 μm
×: Sliding scratch depth 1.0 μm or more
From the results of Tables 2 and 3, the best results were obtained with Co containing 12% by weight, but in the range of 9 to 25% by weight, there was no significant increase in wear or the like on the other side, There was no problem in practical use, and good results were obtained for each. On the other hand, those with 6.5, 30, and 50% by weight had a large amount of wear, and after driving, deterioration of rotation unevenness and generation of abnormal noise were observed.
[0038]
As an effect when Co is contained in WC, the role of a binder for adhering WC to a base material and adhering WC to each other can be mentioned. When the content of Co is small, the adhesion strength is lowered and it is easy to cause degranulation. As a result, it becomes abrasive grains, wear of the counterpart material increases, and rotation unevenness is likely to occur. On the other hand, when the content of Co is large, Co is softer than WC, so that sufficient hardness cannot be obtained for the sprayed film. Therefore, the sliding surface of WC-Co becomes rough, wear of the counterpart material increases, and rotation unevenness occurs. In addition, because of the rough surface of the WC-Co and increased wear of the mating member, abnormal noise is generated during driving.
[0039]
Next, hard alumite is used for the other friction contact portion of the WC-Co sprayed coating according to the present invention which is in frictional contact.
[0040]
FIG. 7 is a cross-sectional view showing an example of a vibration wave motor as an embodiment of the vibration wave driving device of the present invention. In the figure, reference numeral 1 denotes a vibrating body, and two groups of piezoelectric elements 4 polarized in a ring shape as described above are attached to one end face of a ring-shaped metal elastic body 9 made of stainless steel. The friction material 5 is bonded to the other end face of the metal elastic body 9 in the same manner.
[0041]
On the other hand, a friction material 6a is provided on the friction sliding surface of the ring-shaped contact body 6 made of an aluminum alloy on the moving body 2 side. The contact body 6 is attached to a support body 8 via a rubber ring 7, and the support body 8 is fixed to the output shaft 12 with a screw 11. Then, the friction material 5 of the vibrating body 1 and the friction material 6a of the contact body 6 come into contact to form a friction sliding surface, and are pressurized in the axial direction with a load of 5 kgf, for example, in the axial direction by a plate spring 16 for pressurization. Has been. Reference numeral 19 denotes a bearing, reference numeral 13 denotes a cover, reference numerals 14 and 15 denote pressurizing collars, and reference numeral 17 denotes a collar, which are fixed to the output shaft 12 by screws 11a.
[0042]
When an alternating voltage having a frequency unique to the vibrating body 1 is applied to the two groups of piezoelectric elements 4 alternately polarized in the thickness direction, the vibrating body 1 resonates and a progressive vibration wave is generated in the circumferential direction. A frictional force acts on the friction material 6a via the friction material 5, and the moving body 2 is driven to rotate.
[0043]
In the present invention, one frictional contact portion of the vibrating body and the moving body is formed of a sprayed WC-Co sprayed film, and the W / Co / C ternary system is sprayed on the sprayed film. Since the intermetallic compound (η phase) is generated, wear of the frictional contact surface of the vibration motor can be suppressed.
[0044]
In the above-described embodiment, the friction material is applied to the disk-like vibration wave motor shown in FIG. 7, but the friction contact with the above-described friction material provided in the same manner as the rod-like vibration wave motor. A surface may be formed.
[0045]
FIG. 8 is a schematic diagram of an apparatus using the vibration wave motor shown in FIG. 7 as a drive source. Reference numeral 23 denotes a gear having a large gear 23a and a small gear 23b, and the large gear 23a meshes with the gear 20 on the vibration wave motor side. Reference numeral 24 denotes a driven member, for example, a lens barrel. The small gear 23b of the gear 23 is meshed with a gear 24a provided on the outer peripheral portion, and is rotated by the driving force of the motor. On the other hand, an encoder slit plate 25 is attached to the gear 23, and the rotation of the gear 23 is detected by the photocoupler 26, and the rotation and stop of the motor are controlled for autofocusing, for example.
[0046]
【The invention's effect】
As described above, according to the present invention, one frictional contact portion of the vibrating body and the moving body is formed of a sprayed WC-Co sprayed film, and the W · Co · C is sprayed on the sprayed film. The ternary intermetallic compound (η phase) is generated, and a vibration wave drive device with high durability that suppresses wear of the frictional contact surface is obtained.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a frictional contact portion of a ring-shaped vibration wave motor which is an embodiment of the vibration wave drive device of the present invention.
2 is an explanatory view showing a vibrating body of the vibration wave driving device of FIG. 1; FIG.
FIG. 3 is an explanatory diagram showing a driving state of the vibration wave driving device of FIG. 1;
FIG. 4 is an electron micrograph showing the metal structure of a W · Co · C ternary intermetallic compound (η phase) of thermal sprayed tungsten carbide-cobalt (WC-Co) of the present invention.
FIG. 5 is a cross-sectional view showing a WC-Co sliding face after 200 Hr friction sliding of Metco's 71VF-NS (registered trademark) sprayed.
FIG. 6 is a cross-sectional view showing a WC-Co sliding surface after 200 Hr frictional sliding of the powdered WC-Co sprayed.
FIG. 7 is a cross-sectional view showing an example of a vibration wave motor of the present invention.
FIG. 8 is a schematic view of a device using the vibration wave motor shown in FIG. 7 as a drive source.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vibrating body 1a Friction material lb on vibrating body side Protrusion 2 Moving body 2a Contact surface on moving body side 3 Mechanical-electrical energy conversion element 4 Piezoelectric element 5 Friction material 6 Contacting body 6a Friction material 8 Support body 9 Metal elastic body 11, 11a Screw 12 Output shaft 13 Cover 14, 15 Pressure collar 16 Leaf spring 17 Collar 19 Bearing

Claims (6)

In a vibration wave driving device including a vibrating body that generates vibration and a moving body that is in frictional contact with the vibrating body and moves relative to the vibrating body by vibration,
One friction contact portion of the vibrating body and the moving body is formed of a tungsten carbide-cobalt sprayed film, and the sprayed film contains a ternary intermetallic compound of tungsten, cobalt, and carbide. A vibration wave drive device. 2. The vibration wave driving device according to claim 1, wherein the tungsten carbide-cobalt contains 9 to 25% by weight of cobalt . A vibration wave drive device comprising: a vibrating body that generates vibration; and a moving body that frictionally contacts the vibrating body and moves relative to the vibrating body by vibration. In the manufacturing method to form,
  A method for manufacturing a frictional contact portion in a vibration wave driving device, wherein a thermal spray film containing a ternary intermetallic compound of tungsten, cobalt, and carbide is formed by thermal spraying tungsten carbide-cobalt on the surface of the vibrating body. . 4. The manufacturing method according to claim 3, wherein the tungsten carbide-cobalt sprayed film is formed by an HVOF method . 5. The manufacturing method according to claim 4, wherein ethylene is used as a thermal spray fuel for thermal spraying of tungsten carbide-cobalt . 6. The manufacturing method according to claim 3, wherein thermal spraying is performed using a tungsten carbide-cobalt powder that has been sintered or melt-pulverized .

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