JPH04109879A - Vibrator for ultrasonic motor - Google Patents
Vibrator for ultrasonic motorInfo
- Publication number
- JPH04109879A JPH04109879A JP2227443A JP22744390A JPH04109879A JP H04109879 A JPH04109879 A JP H04109879A JP 2227443 A JP2227443 A JP 2227443A JP 22744390 A JP22744390 A JP 22744390A JP H04109879 A JPH04109879 A JP H04109879A
- Authority
- JP
- Japan
- Prior art keywords
- copper
- pores
- vibrating body
- ultrasonic motor
- vibrator
- 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.)
- Pending
Links
- 239000010949 copper Substances 0.000 claims abstract description 22
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910052802 copper Inorganic materials 0.000 claims abstract description 21
- 239000011148 porous material Substances 0.000 claims abstract description 14
- 230000000750 progressive effect Effects 0.000 claims description 7
- 229910001220 stainless steel Inorganic materials 0.000 claims description 6
- 239000010935 stainless steel Substances 0.000 claims description 4
- 239000000463 material Substances 0.000 abstract description 10
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 abstract description 8
- 239000000843 powder Substances 0.000 abstract description 7
- 239000000314 lubricant Substances 0.000 abstract description 4
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical compound [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 abstract description 4
- 239000002245 particle Substances 0.000 abstract description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 abstract description 2
- 230000017525 heat dissipation Effects 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 abstract description 2
- 229910052739 hydrogen Inorganic materials 0.000 abstract 1
- 239000001257 hydrogen Substances 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 5
- 230000008595 infiltration Effects 0.000 description 4
- 238000001764 infiltration Methods 0.000 description 4
- 238000003754 machining Methods 0.000 description 4
- 238000000465 moulding Methods 0.000 description 4
- 238000005245 sintering Methods 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- 239000012768 molten material Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 229910001369 Brass Inorganic materials 0.000 description 1
- 229910000906 Bronze Inorganic materials 0.000 description 1
- 229910017816 Cu—Co Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 229910001297 Zn alloy Inorganic materials 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 239000010951 brass Substances 0.000 description 1
- 239000010974 bronze Substances 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 229910001105 martensitic stainless steel Inorganic materials 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
Landscapes
- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
Description
【発明の詳細な説明】 産業上の利用分野 本発明は、超音波モーター用の振動体に関する。[Detailed description of the invention] Industrial applications The present invention relates to a vibrating body for an ultrasonic motor.
一般に超音波モーターは、現在ではその多くは研究段階
であって、従来技術といえる実用例は極めて少なく、溶
製材による黄銅、リン青銅およびフェライト系ステンレ
ス鋼が使用されていると報告されているにすぎない。In general, most of the ultrasonic motors are currently in the research stage, and there are very few practical examples that can be called conventional technology.It is reported that ingot brass, phosphor bronze, and ferritic stainless steel are used. Only.
また、超音波モーター用として用いる振動体は、進行性
振動波を効率よく利用し、振動体と接触する移動体を駆
動するために、一定の深さをもつスリットをその周上に
数多く設ける必要がある。In addition, the vibrating body used for ultrasonic motors must have many slits of a certain depth around its circumference in order to efficiently utilize progressive vibration waves and drive a moving body that comes into contact with the vibrating body. There is.
しかしながら、溶製材による振動体は、スリットを設け
るために機械加工に頼らなくてはならず、そのため多大
な労力と時間がかかり、コスト的には非常に不利である
。However, the vibrating body made of molten material must rely on machining to provide the slits, which requires a great deal of labor and time, and is very disadvantageous in terms of cost.
問題点を解決するための手段
本発明者は、上記の従来技術における問題点を鑑み鋭意
研究を重ねた結果、溶製材の代わりに粉末成形体の焼結
体を振動体として用いることによって、高精度で且つ安
価に、加工不要のスリットを作成できることを見出し、
さらに焼結体中の内部に介在する気孔に銅を溶浸させる
ことにより、進行性振動波が気孔に吸収されることなく
効率よく移動体を駆動できることを見出した。Means for Solving the Problems As a result of intensive research in view of the problems with the above-mentioned conventional technology, the inventors of the present invention have found that high performance can be achieved by using a sintered body of a powder molded body as a vibrating body instead of molten material. We discovered that it is possible to create slits that do not require machining with high precision and at low cost.
Furthermore, we have discovered that by infiltrating the pores inside the sintered body with copper, it is possible to efficiently drive the moving body without the progressive vibration waves being absorbed by the pores.
即ち、本発明は、下記の超音波モーター用振動体を提供
するものである;
■ 振動体か備えられている圧電素子に周波電圧を印加
することにより、該振動体に進行性振動波を発生せしめ
、該進行性振動波によって該振動体に接触している移動
体を駆動する超音波モーターにおいて、該振動体が焼結
体からなり、該焼結体の気孔中に銅が溶浸されているこ
とを特徴とする超音波用モーター振動体。That is, the present invention provides the following vibrating body for an ultrasonic motor; (1) Generating progressive vibration waves in the vibrating body by applying a frequency voltage to a piezoelectric element provided in the vibrating body; In an ultrasonic motor that drives a moving body in contact with the vibrating body by the progressive vibration waves, the vibrating body is made of a sintered body, and copper is infiltrated into the pores of the sintered body. An ultrasonic motor vibrating body characterized by:
■ 振動体が、Fe系焼結体あるいはオーステナイト系
以外のステンレス鋼系焼結体からなり、該焼結体の気孔
中に銅が溶浸されていることを特徴とする上記の項■記
載の超音波モーター用振動体。■ The vibrating body is made of a Fe-based sintered body or a stainless steel-based sintered body other than austenite, and copper is infiltrated into the pores of the sintered body. Vibrator for ultrasonic motor.
以下、本発明の超音波モーター用振動体について詳細に
説明する。Hereinafter, the vibrating body for an ultrasonic motor of the present invention will be explained in detail.
まず、本発明の焼結体の材質としては、銅の溶浸か可能
なものであればよく、好ましくはFe系焼結体あるいは
オーステナイト系以外のステンレス鋼系の焼結体かよく
、その具体例としてはFe系では、Fe(−C)系、F
e−Cu(−C)系、Fe−N1(−C)系などが挙げ
られる。First, the material of the sintered body of the present invention may be any material that can be infiltrated with copper, preferably a Fe-based sintered body or a stainless steel-based sintered body other than austenitic type, and specific examples thereof As for Fe type, Fe(-C) type, F
Examples include e-Cu (-C) type and Fe-N1 (-C) type.
また、ステンレス鋼系としては、フェライト系ステンレ
ス鋼、マルテンサイト系ステンレス鋼なとが挙げられる
。Further, examples of the stainless steel include ferritic stainless steel and martensitic stainless steel.
また、上記材質の粉体粒度は、通常150μm以下とす
る。Further, the powder particle size of the above material is usually 150 μm or less.
つぎに、成形時においては、粉末冶金法で一般的に行な
われている成形方法を用いればよく、得られる成形体の
密度が6.0〜7 、4 g/cm3程度となるように
成形圧を調節する。また、同時に必要に応じて潤滑剤(
ステアリン酸亜鉛)などの添加剤を加えてもよい。Next, during molding, a molding method commonly used in powder metallurgy may be used, and the molding pressure is adjusted so that the density of the resulting molded product is approximately 6.0 to 7.4 g/cm3. Adjust. At the same time, lubricant (
Additives such as zinc stearate) may also be added.
つづいて、成形体の焼結を常法に従い行なう。Subsequently, the molded body is sintered according to a conventional method.
通常その焼結温度は1000〜1250℃程度、焼結時
間は10〜120分程度で、水素ガスあるいは窒素ガス
などの非酸化性保護雰囲気中で焼結させる。Usually, the sintering temperature is about 1000 to 1250 DEG C., the sintering time is about 10 to 120 minutes, and the sintering is carried out in a non-oxidizing protective atmosphere such as hydrogen gas or nitrogen gas.
ついで、得られた焼結体に銅を溶浸させると本発明の超
音波モーター用振動体が得られる。Next, the obtained sintered body is infiltrated with copper to obtain the vibrating body for an ultrasonic motor of the present invention.
溶浸方法としては、焼結体の上に塊状の銅を置いて、水
素ガスあるいは窒素ガスなどの非酸化性保護雰囲気中1
080〜1150℃程度で10〜120分程度で再び焼
成を行なえばよい。尚、焼結工程と溶浸工程を同時に行
なってもよい。The infiltration method involves placing a lump of copper on top of a sintered body and infiltrating it in a non-oxidizing protective atmosphere such as hydrogen gas or nitrogen gas.
Firing may be performed again at about 080 to 1150°C for about 10 to 120 minutes. Note that the sintering step and the infiltration step may be performed simultaneously.
また、純銅以外で溶浸させることのできるものとしては
、Cu−Co合金、Cu−Fe−Mn−Zn合金などが
例示できる。Examples of materials other than pure copper that can be infiltrated include Cu-Co alloy and Cu-Fe-Mn-Zn alloy.
銅の溶浸量としては、焼結体の内部に存在する気孔のう
ち、溶浸可能な気孔の40%以上に溶浸させることが好
ましい。また、銅の溶浸性を向上させるため、必要に応
じてコバルト、マンガン、鉄などを添加しても差し支え
ない。As for the amount of copper infiltration, it is preferable to infiltrate 40% or more of the pores that can be infiltrated among the pores existing inside the sintered body. Furthermore, in order to improve copper infiltration properties, cobalt, manganese, iron, etc. may be added as necessary.
発明の効果
本発明の超音波モーター用振動体は、粉体よりつくられ
るので、成形時に予めスリットを設けておくことができ
る。したがって、従来のようにスリットの作成を煩雑な
機械加工などに頼る必要がなくなり、省労力化、省エネ
ルギー化などにより、コスト的に非常に有利なものであ
る。Effects of the Invention Since the vibrating body for an ultrasonic motor of the present invention is made of powder, slits can be provided in advance during molding. Therefore, it is no longer necessary to rely on complicated machining to create slits as in the past, and this is very advantageous in terms of cost due to labor and energy savings.
また、焼結体中の気孔に銅を溶浸させることにより、進
行性振動波のエネルギーを移動体に高エネルギー効率で
伝えることができ、さらに従来の溶製材に比べ熱伝導性
、すなわち放熱性に優れているので、結果として高性能
の超音波モーターを得ることができる。In addition, by infiltrating the pores in the sintered body with copper, the energy of progressive vibration waves can be transmitted to the moving body with high energy efficiency, and it also has better thermal conductivity, that is, heat dissipation, than conventional melted materials. As a result, a high-performance ultrasonic motor can be obtained.
実施例
以下、実施例および比較例を示し、本発明の超音波モー
ター用振動体の特徴とするところをより−層明瞭にする
。EXAMPLES Below, Examples and Comparative Examples will be shown to further clarify the features of the vibrating body for an ultrasonic motor of the present invention.
実施例1
100メツシュ通過のFe粉末99.2重量%(以下、
単に%とする)と平均粒子径20μmの炭素粉末0.8
%の割合で混合し、さらに潤滑剤として上記混合物に対
して0,8%のステアリン酸亜鉛を添加した。Example 1 99.2% by weight of Fe powder passing through 100 meshes (hereinafter referred to as
(simply expressed as %) and carbon powder with an average particle size of 20 μm 0.8
%, and 0.8% zinc stearate was added to the mixture as a lubricant.
得られた混合粉末をその密度が7.0g/cm3となる
ように成形を行ない、10mmX 10mmX40mm
の成形体を作成した。The obtained mixed powder was molded so that its density was 7.0 g/cm3, and the size was 10 mm x 10 mm x 40 mm.
A molded body was created.
つきに、この成形体を水素ガス中、1150°Cて1時
間焼結した。Finally, this molded body was sintered in hydrogen gas at 1150°C for 1 hour.
得られた焼結体は、その内部に存在する気孔のうち溶浸
可能な気孔の80%に銅が溶浸されるのに充分な量の銅
を焼結体の上にのせて、水素ガス中、1120°Cで1
時間、銅を溶浸させた。The obtained sintered body is prepared by placing enough copper on the sintered body to infiltrate 80% of the pores that can be infiltrated with hydrogen gas. Medium, 1 at 1120°C
time, the copper was infiltrated.
以上のようにして得られた振動体のQ値を測定したとこ
ろ、第1表のようになった。また第1表には、振動体密
度とコストをあわせて示す。When the Q value of the vibrating body obtained as described above was measured, it was as shown in Table 1. Table 1 also shows the vibrating body density and cost.
さらに、第2表には得られた振動体用いた超音波モータ
ーの特性を示す。Furthermore, Table 2 shows the characteristics of the ultrasonic motor using the obtained vibrator.
実施例2
100メツシュ通過の5US41OL粉末100%と、
これに対し潤滑剤としてステアリン酸亜鉛を0.8%添
加した。Example 2 100% 5US41OL powder passing through 100 meshes,
To this, 0.8% zinc stearate was added as a lubricant.
得られた混合粉末をその密度が6.4g/cm3となる
ように成形し、10mmX 10mmX 40mmの成
形体を作成した。The obtained mixed powder was molded to have a density of 6.4 g/cm 3 to create a molded product measuring 10 mm x 10 mm x 40 mm.
つぎに、この成形体を水素ガス中、1150℃で1時間
焼結した。Next, this molded body was sintered at 1150° C. for 1 hour in hydrogen gas.
得られた焼結体は、その内部に存在する気孔のうち溶浸
可能な気孔の80%に銅が溶浸されるのに充分な量の銅
を焼結体の上にのせて、水素ガス中、1120℃で1時
間、銅を溶浸させた。The obtained sintered body is prepared by placing enough copper on the sintered body to infiltrate 80% of the pores that can be infiltrated with hydrogen gas. Copper was infiltrated for 1 hour at 1120°C.
以上のようにして得られた振動体のQ値を測定したとこ
ろ、第1表のようになった。また第1表には、振動体密
度とコストをあわせて示す。When the Q value of the vibrating body obtained as described above was measured, it was as shown in Table 1. Table 1 also shows the vibrating body density and cost.
さらに、第2表には得られた振動体を用いた超音波モー
ターの特性を示す。Furthermore, Table 2 shows the characteristics of an ultrasonic motor using the obtained vibrator.
比較例1
銅が溶浸されていないという点以外では、実施例1と同
様の方法で得られた振動体のQ値などを測定したところ
、第1表のようになった。Comparative Example 1 The Q value of a vibrating body obtained in the same manner as in Example 1 except that copper was not infiltrated was measured, and the results were as shown in Table 1.
さらに、得られた振動体を用いた超音波モーターの特性
を第2表に示す。Furthermore, Table 2 shows the characteristics of an ultrasonic motor using the obtained vibrator.
比較例2
銅が溶浸されていないという点以外では、実施例2と同
様の方法で得られた振動体のQ値などを測定したところ
、第1表のようになった。Comparative Example 2 The Q value of a vibrating body obtained in the same manner as in Example 2 except that copper was not infiltrated was measured, and the results were as shown in Table 1.
さらに、得られた振動体を用いた超音波モーターの特性
を第2表に示す。Furthermore, Table 2 shows the characteristics of an ultrasonic motor using the obtained vibrator.
比較例3
SUS420J2の溶製材素材を機械加工することによ
って、10mmX 10mmX 40mmの試料体を作
成し、Q値の測定などを行なったところ、第1表のよう
になった。Comparative Example 3 A sample body of 10 mm x 10 mm x 40 mm was prepared by machining a sawn material of SUS420J2, and the Q value was measured, and the results were as shown in Table 1.
さらに、得られた振動体を用いた超音波モーターの特性
を第2表に示す。Furthermore, Table 2 shows the characteristics of an ultrasonic motor using the obtained vibrator.
以上の実施例ならびに比較例の結果、本発明の超音波モ
ーター用の振動体(実施例1および実施例2)は、その
性能面、コスト面などにおいて特に優れた効果を発揮で
きることがわかる。As a result of the above Examples and Comparative Examples, it can be seen that the vibrating body for an ultrasonic motor of the present invention (Example 1 and Example 2) can exhibit particularly excellent effects in terms of performance, cost, etc.
Claims (2)
加することにより、該振動体に進行性振動波を発生せし
め、該進行性振動波によって該振動体に接触している移
動体を駆動する超音波モーターにおいて、該振動体が焼
結体からなり、該焼結体の気孔中に銅が溶浸されている
ことを特徴とする超音波モーター用振動体。(1) By applying a frequency voltage to a piezoelectric element provided with a vibrating body, a progressive vibration wave is generated in the vibrating body, and the moving body that is in contact with the vibrating body is caused by the progressive vibration wave. A vibrating body for an ultrasonic motor to be driven, characterized in that the vibrating body is made of a sintered body, and copper is infiltrated into the pores of the sintered body.
系以外のステンレス鋼系焼結体からなり、該焼結体の気
孔中に銅が溶浸されていることを特徴とする請求項(1
)記載の超音波モーター用振動体。(2) Claim (1) characterized in that the vibrating body is made of an Fe-based sintered body or a stainless steel-based sintered body other than an austenitic body, and copper is infiltrated into the pores of the sintered body.
) Vibrating body for ultrasonic motors.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2227443A JPH04109879A (en) | 1990-08-28 | 1990-08-28 | Vibrator for ultrasonic motor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2227443A JPH04109879A (en) | 1990-08-28 | 1990-08-28 | Vibrator for ultrasonic motor |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH04109879A true JPH04109879A (en) | 1992-04-10 |
Family
ID=16860951
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2227443A Pending JPH04109879A (en) | 1990-08-28 | 1990-08-28 | Vibrator for ultrasonic motor |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH04109879A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05344766A (en) * | 1991-11-27 | 1993-12-24 | Asmo Co Ltd | Stator for ultrasonic motor and manufacture thereof |
-
1990
- 1990-08-28 JP JP2227443A patent/JPH04109879A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05344766A (en) * | 1991-11-27 | 1993-12-24 | Asmo Co Ltd | Stator for ultrasonic motor and manufacture thereof |
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