JP2006064467A

JP2006064467A - Polarizing device for cable-like pressure sensor, and its polarizing method

Info

Publication number: JP2006064467A
Application number: JP2004245560A
Authority: JP
Inventors: Yuko Fujii; 優子藤井; Yu Fukuda; 祐福田
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2004-08-25
Filing date: 2004-08-25
Publication date: 2006-03-09

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems that a flexible pressure sensitive body is entirely hindered from being polarized if it has minute defects, when causing an electrical conductor to act as an outside electrode and that a movement speed is hindered from being enhanced, because of the friction between the electrical conductor and the sensitive body being high. <P>SOLUTION: Friction between the flexible pressure sensitive body 12 and the electrical conductor 16 can be reduced by the provision of a polarizing device for a cable-like pressure sensor, comprising the flexible pressure sensitive body 12 provided around a core electrode 11, the electrical conductor 16 comprising a passage 15 for the sensitive body 12, a film 17 formed on a surface of the passage 15 for reducing the contact resistance between the sensitive body 12 and the electrical conductor 16, a DC voltage generating means 20 connected to the core electrode 11 and to the electrical conductor 16, and a movement means 18 for making the sensitive body 12 move. This enables enhancement of productivity, by enhancing the movement speed of the sensitive body 12, while making it possible to prevent defects from developing on the sensitive body 12 by rubbing thereon caused due to friction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明はケーブル状圧力センサの分極装置および分極方法に関するものである。 The present invention relates to a polarization device and a polarization method for a cable-shaped pressure sensor.

従来、この種のケ−ブル状圧力センサは図４に示すようなものがある（例えば、特許文献１参照）。図４に示すように、芯電極１１の周囲に可撓性感圧体１２を配置し、その周囲に外側電極１３と外皮１４を順次被覆して構成されている。可撓性感圧体１２としては合成ゴムや合成樹脂の中にチタン酸鉛、チタン酸ジルコン酸鉛のセラミック圧電体粉末を添加した複合体が用いられ、外側電極１３は可撓性感圧体１２の表面に銀系ゴム塗料などの導電塗料を塗着したものが用いられている。上記ケ−ブル状圧力センサの一部あるいは全面に圧力が印加されたとき、その部分の圧力センサが歪む結果、芯電極１１と外側電極１３の間に電圧が誘起され、この誘起電圧を利用して圧力を検出している。また、分極方法は、芯電極１１と外側電極１３の間に高電圧を印加して、可撓性感圧体１２を分極している（例えば、非特許文献1参照）。この分極により、セラミック粒子の自発分極の方向が電界方向に揃うので、可撓性感圧体１２に圧電性が付与される。
特開昭６２−２３００７１号公報「圧電セラミック粉末と合成ゴムとから成る圧電複合材料」紛体と工業、２２巻、１号、１９９０年ｐ５０・５６ Conventionally, this type of cable-type pressure sensor is shown in FIG. 4 (see, for example, Patent Document 1). As shown in FIG. 4, a flexible pressure sensitive body 12 is arranged around the core electrode 11, and an outer electrode 13 and an outer skin 14 are sequentially covered around the flexible pressure sensitive body 12. As the flexible pressure-sensitive body 12, a composite in which a ceramic piezoelectric powder of lead titanate or lead zirconate titanate is added to synthetic rubber or synthetic resin is used. The surface is coated with a conductive paint such as silver rubber paint. When pressure is applied to a part or the entire surface of the cable-shaped pressure sensor, the pressure sensor in that part is distorted. As a result, a voltage is induced between the core electrode 11 and the outer electrode 13, and this induced voltage is used. The pressure is detected. In the polarization method, a high voltage is applied between the core electrode 11 and the outer electrode 13 to polarize the flexible pressure sensitive body 12 (see, for example, Non-Patent Document 1). Due to this polarization, the direction of spontaneous polarization of the ceramic particles is aligned with the direction of the electric field, so that piezoelectricity is imparted to the flexible pressure-sensitive body 12.
JP-A-62-230071 "Piezoelectric composite material consisting of piezoelectric ceramic powder and synthetic rubber" Powder and Industry, Vol. 22, No. 1, 1990, p50 / 56

しかしながら、従来のケ−ブル状圧力センサの分極方法では、芯電極１１と外側電極１３の間に高電圧を印加したときに、可撓性感圧体１２中に微小なクラックや空孔などの欠陥が存在する場合、その欠陥部で微小放電が生じる。この微小放電により、可撓性感圧体１２の構成材料が熱的に蒸発、飛散して芯電極１１と外側電極１３間が短絡し、芯電極１１と外側電極１３間に高電圧を印加できなくなるので可撓性感圧体１２を分極できないという課題を有していた。 However, in the conventional polarization method of the cable-shaped pressure sensor, when a high voltage is applied between the core electrode 11 and the outer electrode 13, defects such as microcracks and voids are formed in the flexible pressure sensitive body 12. Is present, a micro discharge is generated at the defective portion. Due to this minute discharge, the constituent material of the flexible pressure-sensitive body 12 is thermally evaporated and scattered, the core electrode 11 and the outer electrode 13 are short-circuited, and a high voltage cannot be applied between the core electrode 11 and the outer electrode 13. Therefore, there was a problem that the flexible pressure sensitive body 12 cannot be polarized.

また、可撓性感圧体１２に外側電極１３を形成し、ほぼケーブル状圧力センサとして構成した後に、芯電極１１と外側電極１３の間に高電圧を印加することでしか欠陥の存在を検出できないので、歩留まりが低下するという課題があった。 In addition, after the outer electrode 13 is formed on the flexible pressure-sensitive body 12 and configured as a substantially cable-shaped pressure sensor, the presence of a defect can be detected only by applying a high voltage between the core electrode 11 and the outer electrode 13. Therefore, there was a problem that the yield decreased.

本発明は、前記従来の課題を解決するもので、欠陥部が存在しても全体の可撓性感圧体１２が分極できなくなることを防ぐとともに、外側電極１３を形成する前に、微小な欠陥が一定長さ範囲内に存在することを検知することで、歩留まり向上を提供することを目的とする。 The present invention solves the above-described conventional problem, and prevents the entire flexible pressure-sensitive body 12 from being unable to polarize even if a defect exists, and allows a minute defect before forming the outer electrode 13. It is an object of the present invention to provide an improvement in yield by detecting that is present within a certain length range.

さらに、可撓性感圧体１２を移動させる移動手段１８を設け、前記可撓性感圧体１２と導電体との接触抵抗を低減するために通路表面に形成された皮膜１７を設けることで、可撓性感圧体１２と導電体間の摩擦を低減し、移動スピードを向上することができるとともに、摩擦によって可撓性感圧体１２にこすれ等で生じる欠陥を防ぐことができ、生産性や信頼性も向上することを目的とする。 Further, it is possible to provide a moving means 18 for moving the flexible pressure sensitive body 12 and to provide a film 17 formed on the passage surface in order to reduce the contact resistance between the flexible pressure sensitive body 12 and the conductor. The friction between the flexible pressure-sensitive body 12 and the conductor can be reduced, the moving speed can be improved, and defects caused by rubbing the flexible pressure-sensitive body 12 due to the friction can be prevented, resulting in productivity and reliability. It aims to improve.

前記従来の課題を解決するために、本発明のケーブル状圧力センサの分極装置は、芯電極に周設された可撓性感圧体と、前記可撓性感圧体の通路を有する導電体と、前記可撓性感圧体と導電体の接触抵抗を低減するために通路表面に形成された皮膜と、前記芯電極と導電体に接続された直流電圧発生手段と、可撓性感圧体を移動させる移動手段とから構成したものである。 In order to solve the above-mentioned conventional problems, a polarization device for a cable-shaped pressure sensor according to the present invention includes a flexible pressure-sensitive body provided around a core electrode, a conductor having a passage of the flexible pressure-sensitive body, A film formed on the surface of the passage to reduce the contact resistance between the flexible pressure-sensitive body and the conductor, DC voltage generating means connected to the core electrode and the conductor, and the flexible pressure-sensitive body are moved. And moving means.

これによって、導電体が外側電極として作用するため、芯電極と導電体間に直流電圧発生手段により直流電圧を印加することにより、導電体に配設された部分の可撓性感圧体を分極する。さらに、導電体の通路表面に形成された皮膜によって前記可撓性感圧体と導電体の接触抵抗を低減するため、可撓性感圧体の移動スピードを向上し生産性を向上できるとともに、摩擦による可撓性感圧体のこすれで生じる欠陥を防ぐことができ、歩留まりや信頼性を向上することができる。 As a result, the conductor acts as an outer electrode, so that a DC voltage is applied between the core electrode and the conductor by the DC voltage generating means to polarize the flexible pressure sensitive body in the portion disposed on the conductor. . Furthermore, since the coating formed on the surface of the conductor passage reduces the contact resistance between the flexible pressure sensitive body and the conductor, the moving speed of the flexible pressure sensitive body can be improved, productivity can be improved, and friction can be improved. Defects caused by rubbing the flexible pressure sensitive body can be prevented, and yield and reliability can be improved.

本発明のケーブル状圧力センサの分極装置は、可撓性感圧体の一部に欠陥部が存在しても全体の可撓性感圧体が分極できなくなることを防ぐとともに、可撓性感圧体と導電体間の摩擦を低減することができるので、可撓性感圧体の移動スピードを向上し、生産性を向上できるとともに、通路中を移動する際の摩擦による可撓性感圧体のこすれで生じる欠陥を防ぐことができるため、ケーブル状圧力センサの分極時の歩留まりや信頼性を向上することができる。 The polarization device for a cable-shaped pressure sensor according to the present invention prevents the entire flexible pressure sensitive body from being polarized even if a defect exists in a part of the flexible pressure sensitive body, Since the friction between the conductors can be reduced, the moving speed of the flexible pressure sensitive body can be improved, the productivity can be improved, and the flexible pressure sensitive body can be rubbed due to the friction when moving in the passage. Since defects can be prevented, the yield and reliability during polarization of the cable-shaped pressure sensor can be improved.

第１の発明は、芯電極に周設された可撓性感圧体と、前記可撓性感圧体の通路を有する導電体と、前記可撓性感圧体と導電体の接触抵抗を低減するために通路表面に形成された皮膜と、前記芯電極と導電体に接続された直流電圧発生手段と、可撓性感圧体を移動させる移動手段とからなるケーブル状圧力センサの分極装置を備えたことにより、可撓性感圧体が通路中を移動する際の導電体との間での摩擦を低減することができる。これにより、可撓性感圧体の移動スピードを向上し生産性を向上できるとともに、摩擦による可撓性感圧体のこすれで生じる欠陥を防ぐことができる。 In order to reduce the contact resistance between the flexible pressure-sensitive body and the conductor, the flexible pressure-sensitive body provided around the core electrode, the conductor having the passage of the flexible pressure-sensitive body, and And a cable-type pressure sensor polarization device comprising a coating formed on the surface of the passage, a DC voltage generating means connected to the core electrode and the conductor, and a moving means for moving the flexible pressure sensitive body. Thus, friction between the flexible pressure-sensitive body and the conductor when moving in the passage can be reduced. Thereby, the moving speed of the flexible pressure sensitive body can be improved and the productivity can be improved, and defects caused by rubbing the flexible pressure sensitive body due to friction can be prevented.

第２の発明は、特に、第１の発明において、皮膜はフッ素樹脂で構成にすることによって、簡単な構成で可撓性感圧体と導電体間の摩擦を低減することができる。 In the second invention, in particular, in the first invention, the film is made of a fluororesin, whereby friction between the flexible pressure-sensitive body and the conductor can be reduced with a simple structure.

第３の発明は、特に、第１の発明において、皮膜はシリコン樹脂で構成にすることによって、簡単な構成で可撓性感圧体と導電体間の摩擦を低減することができる。 In a third aspect of the invention, in particular, in the first aspect of the invention, the film is made of silicon resin, whereby friction between the flexible pressure sensitive body and the conductor can be reduced with a simple structure.

第４の発明は、特に、第１〜第３のいずれか１つの発明において、皮膜を導電体の通路表面に部分的に形成することによって、可撓性感圧体と導電体間の摩擦を低減するとともに直流電圧発生手段からの電圧を効率良く印加することができる。 In particular, in the fourth invention, in any one of the first to third inventions, the friction between the flexible pressure-sensitive body and the conductor is reduced by partially forming the film on the surface of the passage of the conductor. In addition, the voltage from the DC voltage generating means can be applied efficiently.

第５の発明は、特に、第１〜第４のいずれか１つの発明において、皮膜は撥水性能を有することによって、汚れ等の除去が容易になり、効率良い分極が可能となる。 In particular, according to the fifth invention, in any one of the first to fourth inventions, since the film has water repellency, removal of dirt and the like is facilitated, and efficient polarization becomes possible.

第６の発明は、特に、第１〜第５のいずれか１つの発明において、可撓性感圧体を加熱する加熱手段を備えたことにより、可撓性感圧体自身の温度を御することができ、効率良い分極が可能となるため、歩留まりを向上することができる。 In the sixth invention, in particular, in any one of the first to fifth inventions, the heating means for heating the flexible pressure sensitive body is provided, so that the temperature of the flexible pressure sensitive body itself can be controlled. In addition, since efficient polarization is possible, the yield can be improved.

第７の発明は、特に、可撓性感圧体が導電体に設けられた通路に配設され、可撓性感圧体が静止、または移動手段により移動されているとき、前記可撓性感圧体の芯電極と前記導電体の間に直流電圧を印加して分極する方法であり、欠陥部が存在しても全体の可撓性感圧体が分極できなくなることを防ぐとともに、外側電極層あるいは外側電極を形成する前に、微小な欠陥が一定長さ範囲内に存在することを検知することで、歩留まりを向上することができる。 According to a seventh aspect of the present invention, in particular, when the flexible pressure sensing element is disposed in a passage provided in the conductor, and the flexible pressure sensing element is stationary or moved by a moving means, the flexible pressure sensing element is provided. In this method, a DC voltage is applied between the core electrode and the conductor to polarize it, and even if a defect exists, the entire flexible pressure-sensitive body can be prevented from being polarized, and the outer electrode layer or outer By detecting that a minute defect exists within a certain length range before forming the electrode, the yield can be improved.

第８の発明は、特に、可撓性感圧体を加熱する加熱手段を設けたケーブル状圧力センサの分極方法であり、信頼性の高いケーブル状圧力センサを提供することができる。 The eighth invention is a cable-type pressure sensor polarization method provided with heating means for heating a flexible pressure-sensitive body, and can provide a highly reliable cable-type pressure sensor.

第９の発明は、特に、可撓性感圧体の芯電極をアース電位にして、前記芯電極と導電体の間に直流電圧を印加する分極方法であり、人体に危険な直流高電圧部分を導電体に限定できるので、人体への安全を確保できる。 The ninth aspect of the invention is a polarization method in which the core electrode of the flexible pressure sensitive body is set to the ground potential and a DC voltage is applied between the core electrode and the conductor. Since it can be limited to a conductor, safety to the human body can be ensured.

以下、本発明の実施の形態について、図面を参照しながら説明する。なお、この実施の形態によって本発明が限定されるものではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

（実施の形態１）
図１は本発明の実施の形態１におけるケ−ブル状圧力センサの分極装置の構成を示す外観斜視図である。 (Embodiment 1)
FIG. 1 is an external perspective view showing a configuration of a polarization device for a cable-shaped pressure sensor according to Embodiment 1 of the present invention.

図1においてケーブル状圧力センサは芯電極1１に周設された可撓性感圧体１２が形成される。芯電極１1として、コイル状金属線や金属細線を束ねた線などが用いられる。可撓性感圧体１２として、エポキシ樹脂、ウレタン樹脂、クロロプレン樹脂、塩素化ポリエチレン、シリコン樹脂等の高分子母材に、チタン酸ジルコン酸鉛などの高分子材料が用いられる。この可撓性感圧体１２は可撓性感圧体１２の通路１５を有した導電体１６に配設される。導電体１６として、鉄、ステンレス、銅、黄銅、アルミニウム等の導電体を用いる。可撓性感圧体１２の通路１５としては、円形、楕円形、矩形など、可撓性感圧体１２が通過できる形状であれば問題はない。またこの通路１５は切削、研磨、放電、押出、鍛造、プレス加工によって形成した。本発明の実施の形態において、導電体１６はアルミニウムを使用し、通路１５の形状は円形とした。円形にすることによって、芯電極１１の周囲に設けた可撓性感圧体１２の形状に合わせて、均一に直流電圧を印加することができ、安定したセンサ特性を有することができる。具体的には、外形２ｍｍの可撓性感圧体１２に対して通路１５として直径４ｍｍの円形の孔を導電体１６に設けた。さらに通路１５の表面には皮膜１７を形成し、可撓性感圧体１２と導電体１６との接触抵抗を低減する構成となっている。本実施の形態において、皮膜１７はフッ素樹脂として４フッ化エチレンを使用したが、４フッ化エチレンと６フッ化プロピレンの共重合体や、４フッ化エチレン共重合体、４フッ化エチレンパーフロロプロピルビニルテーテルなどを使用してもよく、フッ素樹脂であればよい。 In FIG. 1, the cable-shaped pressure sensor is formed with a flexible pressure-sensitive body 12 that is provided around the core electrode 11. As the core electrode 11, a coiled metal wire or a wire bundled with fine metal wires is used. As the flexible pressure-sensitive body 12, a polymer material such as lead zirconate titanate is used as a polymer base material such as an epoxy resin, a urethane resin, a chloroprene resin, a chlorinated polyethylene, or a silicon resin. The flexible pressure sensitive body 12 is disposed on a conductor 16 having a passage 15 of the flexible pressure sensitive body 12. As the conductor 16, a conductor such as iron, stainless steel, copper, brass, or aluminum is used. There is no problem as long as the passage 15 of the flexible pressure-sensitive body 12 has a shape that allows the flexible pressure-sensitive body 12 to pass, such as a circle, an ellipse, or a rectangle. The passage 15 was formed by cutting, polishing, electric discharge, extrusion, forging, and pressing. In the embodiment of the present invention, the conductor 16 is made of aluminum, and the shape of the passage 15 is circular. By making it circular, a DC voltage can be uniformly applied in accordance with the shape of the flexible pressure-sensitive body 12 provided around the core electrode 11, and stable sensor characteristics can be obtained. Specifically, a circular hole having a diameter of 4 mm was provided in the conductor 16 as a passage 15 for the flexible pressure-sensitive body 12 having an outer diameter of 2 mm. Furthermore, a film 17 is formed on the surface of the passage 15 to reduce the contact resistance between the flexible pressure sensitive body 12 and the conductor 16. In this embodiment, the coating film 17 uses ethylene tetrafluoride as the fluororesin, but a copolymer of ethylene tetrafluoride and propylene hexafluoride, a copolymer of ethylene tetrafluoride, or ethylene tetrafluoride perfluoro. Propyl vinyl tailor may be used as long as it is a fluororesin.

また、可撓性感圧体１２を移動させる移動手段１８として回転ドラムを使用した。この回転ドラムの回転スピードを変化させることによって、可撓性感圧体１２が導電体１６内に配設される時間、言い換えれば分極時間を容易に調整することが可能となる。また、移動手段１８を設けることによって、自動化することができるため、歩留まりを向上することができる。 A rotating drum was used as the moving means 18 for moving the flexible pressure sensitive body 12. By changing the rotation speed of the rotating drum, it is possible to easily adjust the time for which the flexible pressure sensitive body 12 is disposed in the conductor 16, in other words, the polarization time. In addition, since the moving means 18 can be automated, the yield can be improved.

さらに、皮膜１７によって可撓性感圧体１２と導電体１６との摩擦を低減することができるので、移動手段１８のスピードを上げても、導電体１６との擦れによって可撓性感圧体１２に欠陥が生じることを抑制できる。このため、移動スピードの増加も図ることができ、歩留まりや生産性を向上することが可能となる。また、移動スピードを４ｍ／分に設定した場合、皮膜１７を設けない場合の可撓性感圧体１２は、１０ｍに４カ所の亀裂が生じたが、本実施の形態の場合では亀裂箇所は発生しなかった。 Furthermore, since the friction between the flexible pressure-sensitive body 12 and the conductor 16 can be reduced by the film 17, even if the speed of the moving means 18 is increased, the flexible pressure-sensitive body 12 is rubbed by the friction with the conductor 16. It can suppress that a defect arises. For this reason, the movement speed can be increased, and the yield and productivity can be improved. Further, when the moving speed is set to 4 m / min, the flexible pressure-sensitive body 12 when the coating film 17 is not provided has four cracks at 10 m. However, in this embodiment, cracks are generated. I did not.

また、導電体１６はリード線１９ｂによって電気的に接続される。リード線１９ａは電気的に直流電圧発生手段２０の正極または負極に接続され、芯電極１１はリード線１９ａを介して電気的に直流電圧発生手段２０の他の極に接続される。このように接続して、可撓性感圧体１２を直流電圧発生手段２０により、芯電極１１と導電体１６間に高電圧が印加されるので、可撓性感圧体１２が分極される。本実施の形態において印加電圧は８ｋｖ／ｍｍで分極を行った。特に、可撓性感圧体１２の芯電極１１をアース電位にして、芯電極１１と導電体１６の間に直流電圧を印加することで、人体に危険な直流高電圧部分を導電体１６に限定できるので人体への安全を確保できる。また、可撓性感圧体１２の中に微少な欠陥が含まれ、その部分が導電体１６に配設されているとき、欠陥部で生じる微少な放電により導電体１６と芯電極１１間に高電流が流れ、短絡するために分極できなくなるが、欠陥部が導電体１６から脱離し、導電体１６に配設されている可撓性感圧体１２中に欠陥がなければ、導電体１６と芯電極１１間の絶縁性は再び回復するので、分極が可能となる。 The conductor 16 is electrically connected by a lead wire 19b. The lead wire 19a is electrically connected to the positive or negative electrode of the DC voltage generating means 20, and the core electrode 11 is electrically connected to the other pole of the DC voltage generating means 20 via the lead wire 19a. Since the high voltage is applied between the core electrode 11 and the conductor 16 by the DC voltage generation means 20 by connecting the flexible pressure sensitive body 12 in this way, the flexible pressure sensitive body 12 is polarized. In the present embodiment, polarization was performed at an applied voltage of 8 kv / mm. In particular, by applying a DC voltage between the core electrode 11 and the conductor 16 by setting the core electrode 11 of the flexible pressure-sensitive body 12 to the ground potential, a DC high voltage portion that is dangerous to the human body is limited to the conductor 16. It is possible to secure safety to the human body. In addition, when the flexible pressure-sensitive body 12 includes a minute defect and the portion is disposed on the conductor 16, a high discharge is generated between the conductor 16 and the core electrode 11 due to a minute discharge generated in the defect portion. If current flows and short-circuits, polarization becomes impossible, but if the defective portion is detached from the conductor 16 and there is no defect in the flexible pressure-sensitive body 12 provided in the conductor 16, the conductor 16 and the core Since the insulation between the electrodes 11 is restored again, polarization becomes possible.

このように本発明の分極装置によれば、可撓性感圧体の欠陥を含む部分が導電体１６に配設されているときのみ、分極はできないがそれ以外の場合は分極可能となる。従って、欠陥の存在により可撓性感圧体１２が全体にわたって分極できなくなることはない。 As described above, according to the polarization device of the present invention, polarization cannot be performed only when a portion including a defect of the flexible pressure-sensitive body is disposed on the conductor 16, but polarization is possible in other cases. Therefore, the flexible pressure-sensitive body 12 cannot be polarized as a whole due to the presence of defects.

なお、本実施の形態において皮膜１７はフッ素樹脂を使用したが、シリコン樹脂でも同様の効果が得られた。 In the present embodiment, the coating film 17 uses a fluororesin, but a similar effect was obtained with a silicon resin.

また、皮膜１７に撥水性能を持たせることによって、通路１５表面に付着したゴミや可能性圧電体１２に含まれる揮発性物質などを容易に除去することができるため、直流電圧発生手段２０からの電圧をロスすることなく、均一に分極することができるので効率良い分極が可能となる。 Further, by providing the film 17 with water repellency, dust attached to the surface of the passage 15 and volatile substances contained in the potential piezoelectric body 12 can be easily removed. Thus, the polarization can be performed uniformly without losing the voltage, so that efficient polarization is possible.

（実施の形態２）
図２は、本発明の実施の形態２におけるケーブル状圧力センサの分極装置の一部断面図である。図２において実施の形態１と異なるところは、被膜１７を導電体１６の通路１５表面に部分的に形成している点である。なお、第１の実施の形態と同一部材は同じ符号を付けている。 (Embodiment 2)
FIG. 2 is a partial cross-sectional view of a polarization device for a cable-shaped pressure sensor according to Embodiment 2 of the present invention. 2 is different from the first embodiment in that the film 17 is partially formed on the surface of the passage 15 of the conductor 16. The same members as those in the first embodiment are denoted by the same reference numerals.

本構成にすることによって、被膜１７を介すことなく可撓性感圧体１２に直流電圧発生手段２０からの電圧を印加することができるため、皮膜１７による電圧ロスを低減でき、効率良い分極が可能となる。さらに、被膜１７を部分的に形成することで可撓性感圧体１２と導電体１６間の摩擦を低減することができるので、導電体１６との擦れによって可撓性感圧体１２に欠陥が生じることを抑制できる。この結果、導電体１６との擦れによって可撓性感圧体１２に欠陥が生じることを抑制でき、移動スピードの増加が図れ、歩留まりや生産性を向上することが可能となる。 By adopting this configuration, the voltage from the DC voltage generating means 20 can be applied to the flexible pressure sensitive body 12 without the coating 17, so that the voltage loss due to the coating 17 can be reduced and efficient polarization can be achieved. It becomes possible. Furthermore, since the friction between the flexible pressure sensitive body 12 and the conductor 16 can be reduced by partially forming the coating film 17, a defect occurs in the flexible pressure sensitive body 12 due to the friction with the conductor 16. This can be suppressed. As a result, it is possible to suppress the occurrence of defects in the flexible pressure-sensitive body 12 due to rubbing with the conductor 16, increase the moving speed, and improve yield and productivity.

（実施の形態３）
図３は、本発明の実施の形態３におけるケーブル状圧力センサの外観斜視図である。図３において実施の形態１および２と異なるところは、可撓性感圧体１２を加熱する加熱手段２１を設けた点である。なお、第１の実施の形態と同一部材は同じ符号を付けている。 (Embodiment 3)
FIG. 3 is an external perspective view of the cable-shaped pressure sensor according to Embodiment 3 of the present invention. 3 is different from the first and second embodiments in that a heating means 21 for heating the flexible pressure sensitive body 12 is provided. The same members as those in the first embodiment are denoted by the same reference numerals.

図３に示すように、本実施の形態において加熱手段２１は導電体１６を加熱するヒータによって構成したものである。 As shown in FIG. 3, in the present embodiment, the heating means 21 is configured by a heater that heats the conductor 16.

可撓性感圧体１２を分極するときの温度は、それが使用される温度以上でおこなうことが望ましい。それは熱によって可撓性感圧体１２を構成する高分子や添加剤等が熱膨張や組成変形を生じ、分極によってそろった自発分極の方向がずれるため、圧電特性が低下する恐れがあるためである。このため、加熱手段２１によって可撓性感圧体１２の温度を適切に保持し分極することによって、信頼性の高いケーブル状圧力センサを実現することができる。 The temperature at which the flexible pressure sensitive body 12 is polarized is preferably higher than the temperature at which it is used. This is because the polymer, additive, and the like constituting the flexible pressure-sensitive body 12 are thermally expanded and compositionally deformed by heat, and the direction of spontaneous polarization aligned by polarization is deviated, which may reduce the piezoelectric characteristics. . For this reason, a cable-like pressure sensor with high reliability can be realized by appropriately holding and polarizing the temperature of the flexible pressure sensitive body 12 by the heating means 21.

さらに、加熱することによって可撓性感圧体１２表面は柔らかくなるため、導電体１６の通路１５との密着性が増加し、導電体１６と可撓性感圧体１２との摩擦が増加する。このため、移動手段１８のスピードを低下あるいは、可撓性感圧体１２自身にこすれ等による微小な亀裂や欠陥が生じていた。しかし本実施の形態においては、皮膜１７によって、可撓性感圧体１２と導電体１６間の摩擦等を低減できるため、加熱しても、導電体１６との擦れによって可撓性感圧体１２に欠陥が生じることを抑制できるとともに、移動スピードの増加が図れ、歩留まりや生産性を向上することが可能となる。さらに皮膜１７が撥水性能を有することによって、可撓性感圧体１２中に含まれる揮発成分の導電体１６への付着も抑制できるため、効率よい分極も可能となる。 Furthermore, since the surface of the flexible pressure sensitive body 12 is softened by heating, the adhesion between the conductor 16 and the passage 15 is increased, and the friction between the conductor 16 and the flexible pressure sensitive body 12 is increased. For this reason, the speed of the moving means 18 is reduced, or the flexible pressure-sensitive body 12 itself is rubbed with a minute crack or defect. However, in the present embodiment, the film 17 can reduce friction between the flexible pressure sensitive body 12 and the conductor 16, so that even when heated, the flexible pressure sensitive body 12 is caused by rubbing with the conductor 16. It is possible to suppress the occurrence of defects, increase the moving speed, and improve yield and productivity. Furthermore, since the film 17 has water repellency, adhesion of volatile components contained in the flexible pressure-sensitive body 12 to the conductor 16 can be suppressed, so that efficient polarization is also possible.

なお、本実施の形態において加熱手段２１は導電体１６を加熱する構成としたが、可撓性感圧体１２が加熱できればこれに限るものではない。 In the present embodiment, the heating means 21 is configured to heat the conductor 16, but is not limited thereto as long as the flexible pressure sensitive body 12 can be heated.

以上のように、本発明にかかるケ−ブル状圧力センサの分極装置およびその分極方法は、欠陥部が存在しても全体の可撓性感圧体が分極できなくなることを防ぐとともに、被膜を形成することによって、可撓性感圧体と導電体間の摩擦を低減することができるので、可撓性感圧体の移動スピードを向上し、生産性を向上できるとともに、通路表面との摩擦による可撓性感圧体のこすれで生じる欠陥を防ぐことができるので、安定して分極することができる分極装置である。このため、ケーブル状圧力センサに限らず、分極が必要な圧電体の分極に適用できるものである。 As described above, the polarization device for a cable-shaped pressure sensor and the polarization method according to the present invention prevent the entire flexible pressure-sensitive body from being polarized even if a defect exists, and form a coating film. As a result, the friction between the flexible pressure-sensitive body and the conductor can be reduced, so that the movement speed of the flexible pressure-sensitive body can be improved, productivity can be improved, and flexibility due to friction with the passage surface can be improved. Since it is possible to prevent defects caused by rubbing the pressure-sensitive body, the polarization device can be stably polarized. For this reason, it is applicable not only to a cable-shaped pressure sensor but also to polarization of a piezoelectric body that requires polarization.

本発明の実施の形態１における分極装置の構成を示す外観斜視図FIG. 1 is an external perspective view showing a configuration of a polarization device in Embodiment 1 of the present invention. 本発明の実施の形態２における分極装置の構成を示す一部断面図Partial sectional drawing which shows the structure of the polarization apparatus in Embodiment 2 of this invention 本発明の実施の形態３における分極装置の構成を示す外観斜視図External appearance perspective view which shows the structure of the polarization apparatus in Embodiment 3 of this invention. 従来の分極装置の構成を示す外観見取り図Outline drawing showing the configuration of a conventional polarization device

符号の説明Explanation of symbols

１１芯電極
１２可撓性感圧体
１３外部電極
１４外皮
１５通路
１６導電体
１７被膜
１８移動手段
１９リード線
２０直流電圧発生手段
２１加熱手段 DESCRIPTION OF SYMBOLS 11 Core electrode 12 Flexible pressure sensitive body 13 External electrode 14 Outer skin 15 Passage 16 Conductor 17 Coating 18 Movement means 19 Lead wire 20 DC voltage generation means 21 Heating means

Claims

芯電極に周設された可撓性感圧体と、前記可撓性感圧体の通路を有する導電体と、前記可撓性感圧体と導電体の接触抵抗を低減するために通路表面に形成された皮膜と、前記芯電極と導電体に接続された直流電圧発生手段と、前記可撓性感圧体を移動させる移動手段とからなるケーブル状圧力センサの分極装置。 Formed on the surface of the passage to reduce the contact resistance between the flexible pressure-sensitive body and the conductor, and the flexible pressure-sensitive body provided around the core electrode; the conductor having the passage of the flexible pressure-sensitive body; A cable-type pressure sensor polarization device comprising: a coating film; a DC voltage generating means connected to the core electrode and a conductor; and a moving means for moving the flexible pressure sensitive body.

皮膜はフッ素樹脂である請求項１記載のケーブル状圧力センサの分極装置。 2. The polarization device for a cable-shaped pressure sensor according to claim 1, wherein the film is a fluororesin.

皮膜はシリコン樹脂である請求項１記載のケーブル状圧力センサの分極装置。 2. The polarization device for a cable-shaped pressure sensor according to claim 1, wherein the film is made of silicon resin.

皮膜は通路表面に部分的に形成した請求項１〜３のいずれか１項に記載のケーブル状圧力センサの分極装置。 The polarization device for a cable-like pressure sensor according to any one of claims 1 to 3, wherein the film is partially formed on the surface of the passage.

皮膜は撥水性能を有する請求項１〜４のいずれか１項に記載のケーブル状圧力センサの分極装置。 The polarization device for a cable-shaped pressure sensor according to any one of claims 1 to 4, wherein the film has water repellency.

可撓性感圧体を加熱する加熱手段を設けた請求項１〜５のいずれか１項に記載のケーブル状圧力センサの分極装置。 The polarization device for a cable-shaped pressure sensor according to any one of claims 1 to 5, further comprising heating means for heating the flexible pressure sensitive body.

可撓性感圧体が導電体に設けられた通路に配設され、前記可撓性感圧体が静止、または移動手段により移動されているとき、前記可撓性感圧体の芯電極と前記導電体の間に直流電圧を印加するケーブル状圧力センサの分極方法。 When the flexible pressure sensitive body is disposed in a passage provided in the conductor and the flexible pressure sensitive body is stationary or moved by a moving means, the core electrode of the flexible pressure sensitive body and the conductor A polarization method for a cable-type pressure sensor in which a DC voltage is applied between the two.

可撓性感圧体を加熱する加熱手段を設けた請求項７記載のケーブル状圧力センサの分極方法。 The polarization method for a cable-shaped pressure sensor according to claim 7, further comprising a heating means for heating the flexible pressure sensitive body.

可撓性感圧体の芯電極をアース電位にして、前記芯電極と導電体の間に直流電圧を印加する請求項７または８記載のケ−ブル状圧力センサの分極方法。 The polarization method for a cable-shaped pressure sensor according to claim 7 or 8, wherein the core electrode of the flexible pressure-sensitive body is set to ground potential, and a DC voltage is applied between the core electrode and the conductor.