JPH0470531A - Piezoelectric pressure sensor - Google Patents
Piezoelectric pressure sensorInfo
- Publication number
- JPH0470531A JPH0470531A JP18644190A JP18644190A JPH0470531A JP H0470531 A JPH0470531 A JP H0470531A JP 18644190 A JP18644190 A JP 18644190A JP 18644190 A JP18644190 A JP 18644190A JP H0470531 A JPH0470531 A JP H0470531A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- piezoelectric element
- receiving surface
- transfer member
- transmitting member
- 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
- 230000001105 regulatory effect Effects 0.000 claims abstract 3
- 230000005540 biological transmission Effects 0.000 claims description 8
- 239000011347 resin Substances 0.000 claims description 4
- 229920005989 resin Polymers 0.000 claims description 4
- BFKJFAAPBSQJPD-UHFFFAOYSA-N tetrafluoroethene Chemical group FC(F)=C(F)F BFKJFAAPBSQJPD-UHFFFAOYSA-N 0.000 claims description 2
- 238000010008 shearing Methods 0.000 abstract description 4
- 238000009530 blood pressure measurement Methods 0.000 abstract description 2
- 238000002485 combustion reaction Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 3
- 230000002093 peripheral effect Effects 0.000 description 3
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 2
- 239000005977 Ethylene Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
Landscapes
- Measuring Fluid Pressure (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は内燃機関のシリンダ内燃焼圧力等の圧力検出に
適した圧電型圧力センサに関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a piezoelectric pressure sensor suitable for detecting pressure such as combustion pressure in a cylinder of an internal combustion engine.
従来の技術
応力を加えて電荷を発生する圧電効果を利用した圧電型
圧力センサ（表 従来よりよく用いられていも 特に最
近では内燃機関のシリンダ内燃焼圧力等の検出に適した
圧力センサの開発が盛んであム 第３図は特開昭６３−
１０９３４２号公報に述べられている圧電型圧力センサ
の基本構成を示す。同図はセンサの縦断面図であり、セ
ンサ筐体３１内部に設置された圧電素子３４は上部固定
ネジ３５によって圧力伝達部材３３を介してダイアフラ
ム状に加工された受圧面３２の裏面に押しつけられて固
定され 予備応力を与えられていもこの予備応力は特に
内燃機関のシリンダ内燃焼圧力を計測する場合には負圧
を計測するためにも必要であも
次に その動作を説明すａ センサ筐体３１の外部から
受圧面３２に印加された圧力（よ 圧力伝達部材３３を
介して圧電素子３４の内周部分を押し上げるように伝達
される。ここで圧電素子３４の上端外周部は上部固定ネ
ジ３５により下方へ加圧されているた敢 圧電素子３４
に剪断力が加えられも この応力に応じた電荷が発生し
圧電素子３４に設けられた電極（図示せず）から電気
信号として検出する構成となっていも
ここで、センサ筐体３１は金属で形成されているた取
このセンサ筐体３１と圧電素子３４を接触させると圧電
素子３４から発生する電荷がセンサ筐体３１を通じて漏
れて、正確な測定が行われない恐れがあム このため圧
電素子３４とセンサ筺体３１の間には隙間３６ｂを設け
ている。またセンサ筐体３１の内部側面と圧力伝達部材
３３を接触させると圧力伝達部材３３の軸方向の運動が
スムーズに行われなくなり、圧力が受圧面３２から圧電
素子３４へ正確に伝わらなくなる可能性があん この運
動をスムーズに行わせるためにはセンサ筐体３１の内壁
を研磨することが必要となり、これではコストが高くな
るという欠点があるので圧力伝達部材３３とセンサ筐体
３１の間にも隙間３６ａを設けている。Conventional technologyPiezoelectric pressure sensors that utilize the piezoelectric effect that generates electric charges by applying stress Figure 3 is JP-A-63-
The basic configuration of a piezoelectric pressure sensor described in Japanese Patent No. 109342 is shown. The figure is a longitudinal sectional view of the sensor, in which the piezoelectric element 34 installed inside the sensor housing 31 is pressed by the upper fixing screw 35 against the back surface of the pressure receiving surface 32 processed into a diaphragm shape via the pressure transmitting member 33. Even if the sensor housing is fixed and given a prestress, this prestress is also necessary to measure the negative pressure, especially when measuring the combustion pressure in the cylinder of an internal combustion engine. Pressure applied to the pressure receiving surface 32 from the outside of the body 31 is transmitted through the pressure transmission member 33 so as to push up the inner circumference of the piezoelectric element 34. Here, the upper outer circumference of the piezoelectric element 34 is connected to the upper fixing screw The piezoelectric element 34 is pressurized downward by the piezoelectric element 35.
Even if a shearing force is applied to the piezoelectric element 34, a charge corresponding to the stress is generated and detected as an electrical signal from an electrode (not shown) provided on the piezoelectric element 34. However, here, the sensor housing 31 is made of metal. The hole being formed
If the sensor housing 31 and the piezoelectric element 34 are brought into contact with each other, the electric charge generated from the piezoelectric element 34 may leak through the sensor housing 31, leading to inaccurate measurements. A gap 36b is provided between them. Furthermore, if the inner side surface of the sensor housing 31 and the pressure transmitting member 33 come into contact, the axial movement of the pressure transmitting member 33 will not be performed smoothly, and there is a possibility that the pressure will not be accurately transmitted from the pressure receiving surface 32 to the piezoelectric element 34. In order to perform this movement smoothly, it is necessary to polish the inner wall of the sensor housing 31, which has the disadvantage of increasing costs, so there is also a gap between the pressure transmitting member 33 and the sensor housing 31. 36a is provided.
発明が解決しようとする課題
しかしなが収 上記構成の圧電型圧力センサでは圧力伝
達部材３３とセンサ筐体３１の間の隙間３６ａや圧電素
子３４とセンサ筐体３１の間の隙間３６ｂのた取 圧力
伝達部材３３や圧電素子３４の軸方向が受圧面に対して
直角に取り付けられていないこと、あるいは受圧面３２
、圧力伝達部材３３、圧電素子３４の中心が一致しない
ことが多くなム これでは受圧面３２から圧電素子３４
への圧力伝達の隘 圧力伝達部材３３や圧電素子３４に
片当りが生二 これらの部分が破損する場合があり、圧
力の伝達や測定が正確に行なえないという問題があっ九
本発明ζよ 受圧面が外部から受けた圧力を圧力伝達部
材を介して圧電素子に正確に伝え 圧力測定が正確に行
える圧電型圧力センサを提供することを目的とすａ
課題を解決するための手段
本発明は上記課題を解決するた嵌 圧力伝達部材や圧電
素子の位置決めガイドをセンサ筐体の内部に設けも
作 用
本発明は圧力伝達部材の位置決めガイドを設けることに
より圧力伝達部材や圧電素子を受圧面の中心に直角に取
り相法 保持することができも実施例
以下、図面を参照して本発明の圧電型圧力センサの一実
施例について説明すも
第１図は本発明の実施例における圧電型圧力センサの断
面を示す。同図中１１は金属からなるセンサ筺体であり
、このセンサ筐体１１の一面にダイアフラム状に加工さ
れた受圧面１２を設けていａ この受圧面１２は被測定
領域 例えば内燃機関のシリンダ九 に設置されてい４
センサ筐体１１の内部にはセラミックで形成された圧
力伝達部材１３の一端が受圧面１２の裏面に接するよう
に設けられ 他端には円筒形の圧電素子１４が設けられ
ていも この円筒形の圧電素子１４の下方内周部分は圧
力伝達部材１３が保持している。さらに圧電素子１４の
上端外周部分を上部固定ネジ１５によって押さえつけて
いも この上部固定ネジ１５の締め付は力によって圧電
素子１４及び圧力伝達部材１３を受圧面１２に押し付け
、各部材の固定及び圧電素子１４への予備応力を印加し
ていも ま７−、１６は位置決めガイドであり、圧力伝
達部材１３とセンサ筐体１１の間に配置され圧力伝達部
材１３の位置を規制するように設けられている。Problems to be Solved by the Invention However, in the piezoelectric pressure sensor having the above configuration, the gap 36a between the pressure transmitting member 33 and the sensor housing 31 and the gap 36b between the piezoelectric element 34 and the sensor housing 31 can be removed. The axial direction of the pressure transmitting member 33 or the piezoelectric element 34 is not installed at right angles to the pressure receiving surface, or the pressure receiving surface 32
In many cases, the centers of the pressure transmitting member 33 and the piezoelectric element 34 do not coincide with each other.
Problems with transmitting pressure to the pressure transmitting member 33 and piezoelectric element 34 Occasionally, these parts may be damaged, resulting in the problem that pressure cannot be transmitted or measured accurately. An object of the present invention is to provide a piezoelectric pressure sensor that accurately transmits the pressure that a surface receives from the outside to a piezoelectric element via a pressure transmitting member and can accurately measure pressure. In order to solve the problem, it is also possible to provide a positioning guide for the pressure transmitting member and the piezoelectric element inside the sensor housing. An embodiment of the piezoelectric pressure sensor of the present invention will be described below with reference to the drawings. Fig. 1 shows a piezoelectric pressure sensor according to an embodiment of the present invention. A cross section of is shown. In the figure, reference numeral 11 denotes a sensor housing made of metal, and a pressure receiving surface 12 processed into a diaphragm shape is provided on one side of the sensor housing 11. This pressure receiving surface 12 is installed in a measurement area, for example, a cylinder 9 of an internal combustion engine. has been done 4
Inside the sensor housing 11, one end of a pressure transmitting member 13 made of ceramic is provided so as to be in contact with the back surface of the pressure receiving surface 12, and a cylindrical piezoelectric element 14 is provided at the other end. A pressure transmitting member 13 holds the lower inner peripheral portion of the piezoelectric element 14 . Furthermore, even if the outer circumferential portion of the upper end of the piezoelectric element 14 is held down by the upper fixing screw 15, the tightening of the upper fixing screw 15 uses force to press the piezoelectric element 14 and the pressure transmitting member 13 against the pressure receiving surface 12, fixing each member and fixing the piezoelectric element. 7-, 16 is a positioning guide, which is disposed between the pressure transmission member 13 and the sensor housing 11 and is provided to regulate the position of the pressure transmission member 13. .
センサ筺体１１の内部側壁と受圧面１２は直角となるよ
う精密加工され 位置決めガイド１６の厚みも各部とも
等しくなるよう精密に加工されていも また センサ筺
体１１と位置決めガイド１６は はめあい加工され 位
置決めガイド１６と圧力伝達部材１３もはめあい加工さ
れている。したがって、センサ筺体１１、位置決めガイ
ド１６、圧力伝達部材１３の組立に際し 圧力伝達部材
１３は受圧面１２に対し直角が高精度に保たれていも
次に 本実施例の圧電型圧力センサの動作について説明
すも 被測定領域の圧力が受圧面１２に加わると、その
力は圧力伝達部材１３を通して圧電素子１４の下方内周
部分に伝えられる。一方、圧電素子１４の上方外周部分
は上部固定ネジ１５によって押さえられているのて そ
の結果 圧電素子１４に剪断力が加えられ この加えら
れた力に応じた電荷が圧電素子に発生する。この電荷を
電気信号として検出する。Although the inner side wall of the sensor housing 11 and the pressure receiving surface 12 are precisely machined so that they are at right angles, and the thickness of the positioning guide 16 is also precisely machined so that each part is equal, the sensor housing 11 and the positioning guide 16 are machined to fit, and the positioning guide 16 The pressure transmitting member 13 is also fitted. Therefore, when assembling the sensor housing 11, positioning guide 16, and pressure transmitting member 13, even if the pressure transmitting member 13 is kept perpendicular to the pressure receiving surface 12 with high precision, the operation of the piezoelectric pressure sensor of this embodiment will be explained next. When the pressure of the area to be measured is applied to the pressure receiving surface 12, the force is transmitted to the lower inner peripheral portion of the piezoelectric element 14 through the pressure transmitting member 13. On the other hand, since the upper outer peripheral portion of the piezoelectric element 14 is held down by the upper fixing screw 15, a shearing force is applied to the piezoelectric element 14, and an electric charge corresponding to this applied force is generated in the piezoelectric element. This charge is detected as an electrical signal.
ここで、位置決めガイド１６（主 圧力伝達部材１３が
圧力を圧電素子１４に伝える動作を阻害せず、かつ圧力
伝達部材１３の位置を規制しなければならな（−例えば
四ふっ化エチレン樹脂（テフロン）は自己潤滑性がある
ので位置決めガイド１６の材質として用いたとき、圧力
伝達ロスを排除でき高精度の圧力センサを構成できる。Here, the positioning guide 16 (main pressure transmitting member 13 must not inhibit the operation of transmitting pressure to the piezoelectric element 14 and must regulate the position of the pressure transmitting member 13 (for example, tetrafluoroethylene resin (Teflon) ) has self-lubricating properties, so when used as the material for the positioning guide 16, pressure transmission loss can be eliminated and a highly accurate pressure sensor can be constructed.
また 圧力は圧電素子１４で発生した電荷として検出さ
れも このた嵌 低い圧力周波数まで高精度に検出する
ためには電荷の漏れを最小限に抑えなければならな（ｔ
四ぶつ化エチレン樹脂は絶縁性が高いので位置決めガ
イド１６の材料としてこれを用いると、位置決めガイド
１６と圧電素子１４との接触面から電荷が漏れる恐れも
なく、低周波まで高精度に圧力測定ができる圧電型圧力
センサを実現できも
第２図（友 第１図の位置決めガイド１６を位置決めガ
イド２１のように変更した場合の実施例を示す。位置決
めガイド２１は圧電素子１４ともはめあい加工されてい
るので、圧力伝達部材１３と圧電素子１４の中心も高精
度で一致すも このため圧力伝達部材１３と圧電素子１
４の間の片当りによる応力集中が排除されるので、圧力
伝達部材１３や圧電素子１４の破損が回避できも 従っ
て、受圧面１２に与えられた圧力は更に確実に圧電素子
１４に伝えられ 更に高精度で信頼性の高い圧電型圧力
センサを構成できる。In addition, pressure is detected as a charge generated by the piezoelectric element 14, but in order to detect pressure down to low pressure frequencies with high precision, leakage of charge must be minimized (t
Tetrabutylene ethylene resin has high insulating properties, so if it is used as the material for the positioning guide 16, there is no risk of charge leaking from the contact surface between the positioning guide 16 and the piezoelectric element 14, and pressure measurement can be performed with high accuracy up to low frequencies. Figure 2 shows an example in which the positioning guide 16 in Figure 1 is changed to a positioning guide 21.The positioning guide 21 is also fitted with the piezoelectric element 14. Therefore, the centers of the pressure transmitting member 13 and the piezoelectric element 14 also coincide with each other with high precision.
Since stress concentration due to uneven contact between the pressure-receiving surface 12 and the piezoelectric element 14 is eliminated, damage to the pressure transmitting member 13 and the piezoelectric element 14 can be avoided. A highly accurate and reliable piezoelectric pressure sensor can be constructed.
以上説明したように圧力伝達部材は位置決めガイドによ
り受圧面の中央に直角に取り付けられて、片当りが排除
され 応力集中による圧力伝達部材の破損が回避される
ので、受圧面に与えられた圧力を確実に圧電素子に伝え
ることができ、高精度で信頼性の高い圧電型圧力センサ
を提供できる。As explained above, the pressure transmitting member is mounted perpendicularly to the center of the pressure receiving surface by the positioning guide, eliminating uneven contact and avoiding damage to the pressure transmitting member due to stress concentration, so that the pressure applied to the pressure receiving surface is It is possible to provide a highly accurate and reliable piezoelectric pressure sensor that can reliably transmit information to the piezoelectric element.
な耘 本実施例では圧電素子に剪断力を与えることによ
り電気信号を取り出し 圧力測定を行っている力（剪断
力に限らず圧縮力を与えるような構成であっても良い。In this embodiment, an electric signal is extracted by applying a shearing force to the piezoelectric element, and the pressure is measured.
また 本実施例では位置決めガイドとして四ふっかエチ
レン樹脂を用いている力丈 これに限るわけではなく、
絶縁性が良く、潤滑性のよい材料であれば良し〜
発明の効果
以上のように 本発明により、センサ筺体内部に位置決
めガイドを備えることにより、受圧砥圧力伝達部材、圧
電素子の接触面で応力集中が無く、圧力伝達部材や圧電
素子の破損が無いので、正確な圧力伝達が行われ 耐久
性に優れた高精度の圧電型圧力センサが実現できる。In addition, in this example, the strength is not limited to that of the four-fluoride ethylene resin used as the positioning guide.
Any material with good insulating properties and good lubricity is sufficient.As described above, according to the present invention, by providing a positioning guide inside the sensor housing, stress is applied to the contact surface of the pressure-receiving abrasive pressure transmitting member and the piezoelectric element. Since there is no concentration and there is no damage to the pressure transmitting member or piezoelectric element, a highly accurate piezoelectric pressure sensor with excellent pressure transmission and excellent durability can be realized.
第１皿 第２図は本発明の一実施例における圧電型圧力
センサの断面図 第３図は従来の圧電型圧力センサの断
面図であム
１１、３１・・−・・センサ筺ａ １２、３２・・−
・・受圧献 １３、３３・・−・・圧力伝達部材、 １
４、３４・・−・・圧電素子、 １５、３５・・−・・
上部固定ネジ、 １６、２１・・−・・位置決めガイド
。
代理人の氏名 弁理士 粟野重孝 ほか１名弔
図
第 ２
図
＼／Ｚｔ反記
゛ゝｌ？受氏面
第 ３
＼
３Ｓご部固定ネジ
／
３２受玉面1. Fig. 2 is a sectional view of a piezoelectric pressure sensor according to an embodiment of the present invention. Fig. 3 is a sectional view of a conventional piezoelectric pressure sensor. 32...-
...Pressure receiving member 13, 33...Pressure transmission member, 1
4, 34...Piezoelectric element, 15, 35...
Upper fixing screw, 16, 21...Positioning guide. Name of agent: Patent attorney Shigetaka Awano and one other person Funeral map No. 2 Figure ＼／Zt counternote ゛ゝl? Uke face No. 3 ＼ 3S part fixing screw / 32 receive ball face
Claims (3)
れかつ一端が前記受圧面の裏側の面に接する圧力伝達部
材と、前記筐体の内部に設けられかつ前記圧力伝達部材
の他端に設けられた圧電素子から構成され、前記圧電素
子の側面と前記筺体との間に隙間を有し、前記圧力伝達
部材の位置を規制する位置決めガイドを前記圧力伝達部
材の側面と前記筐体の間に設けたことを特徴とする圧電
型圧力センサ。(1) A casing having a pressure receiving surface, a pressure transmitting member provided inside the casing and having one end in contact with the back side of the pressure receiving surface, and the other end of the pressure transmitting member provided inside the casing. A positioning guide for regulating the position of the pressure transmitting member is provided between the side surface of the pressure transmitting member and the housing, and has a gap between the side surface of the piezoelectric element and the housing. A piezoelectric pressure sensor characterized by being provided between.
れかつ一端が前記受圧面の裏側の面に接する圧力伝達部
材と、前記筺体の内部に設けられかつ前記圧力伝達部材
の他端に設けられた圧電素子から構成され、前記圧電素
子の位置および前記圧力伝達部材の位置を規制する位置
決めガイドを前記圧電素子の側面と前記筺体との間およ
び前記圧力伝達部材の側面と前記筺体の間に設けたこと
を特徴とする圧電型圧力センサ。(2) a casing having a pressure receiving surface; a pressure transmitting member provided inside the casing and having one end in contact with the back surface of the pressure receiving surface; and a pressure transmitting member provided inside the casing and having the other end of the pressure transmitting member A positioning guide consisting of a piezoelectric element provided and regulating the position of the piezoelectric element and the position of the pressure transmission member is provided between the side surface of the piezoelectric element and the housing and between the side surface of the pressure transmission member and the housing. A piezoelectric pressure sensor characterized by being provided with.
れていることを特徴とする請求項１又は２記載の圧電型
圧力センサ。(3) The piezoelectric pressure sensor according to claim 1 or 2, wherein the positioning guide is made of tetrafluoroethylene resin.
Priority Applications (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18644190A JPH0470531A (en) | 1990-07-12 | 1990-07-12 | Piezoelectric pressure sensor |
| TW080101770A TW221491B (en) | 1990-03-16 | 1991-03-05 | |
| US07/668,256 US5138885A (en) | 1990-03-16 | 1991-03-12 | Piezoelectric-type pressure sensor |
| CA002038226A CA2038226C (en) | 1990-03-16 | 1991-03-14 | Piezoelectric-type pressure sensor |
| EP91302229A EP0447255B1 (en) | 1990-03-16 | 1991-03-15 | Piezoelectric-type pressure sensor |
| DE69106411T DE69106411T2 (en) | 1990-03-16 | 1991-03-15 | Piezoelectric pressure transducer. |
| ES91302229T ES2066347T3 (en) | 1990-03-16 | 1991-03-15 | PIEZOELECTRIC TYPE PRESSURE SENSOR. |
| EP19930114634 EP0574046A3 (en) | 1990-03-16 | 1991-03-15 | Piezoelectric-type pressure sensor |
| KR1019910004198A KR910017178A (en) | 1990-03-16 | 1991-03-16 | Piezoelectric Pressure Sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18644190A JPH0470531A (en) | 1990-07-12 | 1990-07-12 | Piezoelectric pressure sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0470531A true JPH0470531A (en) | 1992-03-05 |
Family
ID=16188504
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18644190A Pending JPH0470531A (en) | 1990-03-16 | 1990-07-12 | Piezoelectric pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0470531A (en) |
-
1990
- 1990-07-12 JP JP18644190A patent/JPH0470531A/en active Pending
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