JPS59153140A - Pressure detector - Google Patents
Pressure detectorInfo
- Publication number
- JPS59153140A JPS59153140A JP2790783A JP2790783A JPS59153140A JP S59153140 A JPS59153140 A JP S59153140A JP 2790783 A JP2790783 A JP 2790783A JP 2790783 A JP2790783 A JP 2790783A JP S59153140 A JPS59153140 A JP S59153140A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- flexible
- flexible membranes
- rubber diaphragm
- flexible films
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0041—Transmitting or indicating the displacement of flexible diaphragms
- G01L9/007—Transmitting or indicating the displacement of flexible diaphragms using variations in inductance
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は可撓膜を用いて圧力を検出する圧力検出器に関
し、特に温度変化に、Lる出力の変動を1クツ。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a pressure sensor that detects pressure using a flexible membrane, and particularly to a pressure sensor that detects pressure due to temperature changes.
ぐ圧力検出器の構造に関するものである。This paper relates to the structure of a pressure sensor.
従来例の構成とその問題点
第1図は従来の可撓膜を用いた圧力検出器の構成図であ
り、第2図は第1図の要部を示すものでその動作説明図
である。第1図により構造を説明する。1は可撓膜とし
てのゴムダイアフラムであシ、その中心部を支持板2と
支持板3により支持されている。4は差動トランスでコ
アロッド5、コア6、コイ)v7より構成されている。Structure of a conventional example and its problems FIG. 1 is a block diagram of a conventional pressure detector using a flexible membrane, and FIG. 2 shows the main part of FIG. 1 and is an explanatory diagram of its operation. The structure will be explained with reference to FIG. Reference numeral 1 denotes a rubber diaphragm as a flexible membrane, the center of which is supported by support plates 2 and 3. 4 is a differential transformer, which is composed of a core rod 5, a core 6, and a coil (coil) v7.
前記コアロッド5は前記支持板2,3に固定されている
。The core rod 5 is fixed to the support plates 2 and 3.
8は可撓膜1の上部に設けられた。圧力導入口9を有す
る上部密閉室である。10は可撓膜1の下部に設けられ
た圧力導入口11を有する下部密閉室、12.13はそ
れぞれダイヤフラム支持ばねである。8 was provided on the upper part of the flexible membrane 1. This is an upper sealed chamber having a pressure introduction port 9. 10 is a lower sealed chamber having a pressure introduction port 11 provided at the lower part of the flexible membrane 1, and 12 and 13 are diaphragm support springs, respectively.
圧力心入口つと圧力導入口11からの流体差圧に応じて
ゴムダイアフラム1がダイヤフラム支持ばね12企るい
はダイヤフラム支持ばね13を圧縮しながら」二下に移
動する。その動きによってコアロッド5に連結されたコ
ア6が移動し、差圧に応じた出力をとりだすものである
。ところがこの従来の構造の圧力検出器は差圧が一定の
場合においても周囲温度の変化により出力が変化すると
いう問題があった。第2図によって説明する。第2図は
第1図中、可撓膜1の部分を示したものである。基準温
度状態での可撓膜1の位1ぷをS−Sとしたとき、周囲
温度が上昇した場合の動作を説明する。線膨張係数の大
なるゴムダイヤフラム1の膨張によシビード部Cの曲率
が小さくなるように変形するがその部分の応力を緩和す
べくゴムダイヤフラム1の中央部分はA−Aに示すよう
に下方に変位し、それと連結されたコア6も下方に変位
し、出力が変化する。周囲温度が低下した場合には線膨
張係数の大なるゴムダイヤフラム1の収縮作用により、
ビード部Cが引っ張られて全体として平板状になろうと
して中火の平面部S−Sはその結果B−BJで上方に移
動し、出力が変化する。The rubber diaphragm 1 moves downward while compressing the diaphragm support spring 12 or 13 in response to the fluid pressure difference from the pressure core inlet and the pressure introduction port 11. This movement causes the core 6 connected to the core rod 5 to move, thereby producing an output according to the differential pressure. However, this conventional pressure detector has a problem in that its output changes due to changes in ambient temperature even when the differential pressure is constant. This will be explained with reference to FIG. FIG. 2 shows a portion of the flexible membrane 1 in FIG. 1. Assuming that the position of the flexible membrane 1 in the standard temperature state is S-S, the operation when the ambient temperature rises will be explained. Due to the expansion of the rubber diaphragm 1, which has a large coefficient of linear expansion, the curvature of the shabby portion C is deformed to become smaller, but in order to relieve the stress in that portion, the center portion of the rubber diaphragm 1 is moved downward as shown in A-A. The core 6 that is displaced and connected to it is also displaced downward, and the output changes. When the ambient temperature drops, due to the contraction of the rubber diaphragm 1, which has a large coefficient of linear expansion,
The bead portion C is pulled and becomes flat as a whole, and the medium-heated flat portion S-S moves upward at B-BJ as a result, and the output changes.
このため出力信号を電気的に補正する機rjしが必要と
なり、コヌト的にも1°Fjいものにな−/とりl+、
7に零点付近で高精度を要求する場合には使用不11能
となっていた。For this reason, a mechanism for electrically correcting the output signal is required, and it becomes 1°Fj worse in terms of the output signal.
However, when high precision is required near the zero point, it cannot be used.
発明の目的
本発明は可撓膜で差圧を受け、差圧に応じて可撓膜に変
位を発生させて差圧信号をとシだす圧力検出器の温度特
性改善、すなわち圧力検出器の出力が温度依存性を持た
ないようにすることを目的とする。Purpose of the Invention The present invention aims to improve the temperature characteristics of a pressure sensor that receives a pressure difference through a flexible membrane and generates a pressure difference signal by generating a displacement in the flexible membrane in accordance with the pressure difference, that is, to improve the output of the pressure sensor. The purpose is to ensure that there is no temperature dependence.
発明の構成
上記の目的を達成するために、略同−形状の2個の可撓
膜を同軸状態でかつ軸方向に互いに逆向き(背中合わせ
)に配置し、かつそれら2個の可撓膜の外縁部は一定間
隔を保って固定的に設けられ、中心部は一定間隔を保っ
たま1軸方向に変位可能となっている。両可撓膜の外面
側にそれぞれの可撓膜を1つの壁面とする密閉室を設け
ている。Structure of the Invention In order to achieve the above object, two flexible membranes having substantially the same shape are arranged coaxially and opposite each other in the axial direction (back to back), and the two flexible membranes are The outer edge portions are fixedly provided at a constant interval, and the center portion is movable in one axis direction while maintaining a constant interval. A sealed chamber with each flexible membrane as one wall is provided on the outer surface side of both flexible membranes.
それぞ柱の密閉室に流体圧力を作用させて流体差圧に応
じた変位を可撓膜に発生させ、その変位を電気信号に変
換するよう構成している。The structure is such that fluid pressure is applied to the sealed chamber of each column to generate a displacement in the flexible membrane according to the fluid pressure difference, and the displacement is converted into an electrical signal.
背中αせに同軸状態で設けられた2個の可撓膜は周囲温
度の変化にともなって膨張、収縮し、その結果、可撓膜
が変形し、その変形に基いて応力が発生するが、その応
力の軸方向成分は、略同−形状の可撓膜が背中合せに設
けられているため互いに打ち消し合って外部に現れるこ
とがない。すなわち周囲温度の変化に伴ってi’if撓
膜が変位することかなく、温度変化によって出力が変化
するととがない。The two flexible membranes coaxially provided on the back expand and contract as the ambient temperature changes, and as a result, the flexible membranes deform, and stress is generated based on the deformation. Since the flexible membranes having substantially the same shape are provided back to back, the axial components of the stress cancel each other out and do not appear outside. That is, the i'if flexural membrane does not displace due to changes in ambient temperature, and the output does not change due to changes in temperature.
実施例の説明
本発明の一実施例を第3図に示す。本実施例し]:ガス
燃焼装置の燃焼空気圧ツノと燃料ガス圧力の差圧を検出
してこれを〒定値に保って空気過剰率を一定に保つもの
である。制御部は省略している。DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention is shown in FIG. This embodiment]: The differential pressure between the combustion air pressure horn of the gas combustion device and the fuel gas pressure is detected and kept at a constant value to keep the excess air ratio constant. The control unit is omitted.
先ず構成を説明する。2oは本発明にJl(<圧力検出
器、21はガス燃焼装置のバーす1(11である。First, the configuration will be explained. 2o is Jl (<pressure detector) in the present invention, and 21 is bar 1 (11) of the gas combustion device.
次に詳細R’i’7造を説明する。22および23は1
げ撓膜としての第1のゴムダイアフラム、第2のコア゛
ムダイアフラムであシそれぞれ外周部にビード22 B
、 23 Bを有している。両者の間に中心部に孔を
有するヌペーザ24が設けられ支持板25、支持板26
、コアロッド2γとともに2枚のゴノ、ダイアフラムを
背中合せに一定間内に保つようになっている。変位量−
電気信号変換部としての差動トランスは前記コアロッド
27、コア28およびコイ/l/29よシ構成されてい
る。30は可撓膜としての第1のゴムダイアフラム22
の上部に設けられた、圧力導入口31を有する上部密閉
室、32は第2のゴムダイアフラム23の下部に設けら
れた圧力導入口33を有する下部密閉室、34は基準圧
力導入口35を荷する基準圧力室である。Next, the details of R'i'7 construction will be explained. 22 and 23 are 1
The first rubber diaphragm and the second core diaphragm serve as flexible membranes, each having a bead 22B on the outer periphery.
, 23B. A Nupeza 24 having a hole in the center is provided between the two, and a support plate 25 and a support plate 26 are provided.
, the core rod 2γ, two gonos and diaphragms are kept back to back within a certain distance. Displacement -
A differential transformer serving as an electric signal converter is composed of the core rod 27, core 28, and coil/l/29. 30 is a first rubber diaphragm 22 as a flexible membrane.
32 is a lower sealed chamber provided at the bottom of the second rubber diaphragm 23 and has a pressure introduction port 33; 34 is a reference pressure introduction port 35; This is the reference pressure chamber.
36.37はそれぞれダイアフラム支持ばねである。次
にバーナ部21の構造を説明する。38は燃料ガス圧力
導管口39を有するガスノズル、40は燃焼空気圧力検
出口41を有する燃焼空気チャンバである。42は混合
圧力検出口43を有する混合部である。なお44は燃料
ガス圧力導管、45は燃焼空気圧力導管、46は基準圧
力導管である。47は燃焼室である。次に動作を説明す
る。36 and 37 are diaphragm support springs, respectively. Next, the structure of the burner section 21 will be explained. 38 is a gas nozzle having a fuel gas pressure conduit port 39, and 40 is a combustion air chamber having a combustion air pressure detection port 41. 42 is a mixing section having a mixing pressure detection port 43. Note that 44 is a fuel gas pressure conduit, 45 is a combustion air pressure conduit, and 46 is a reference pressure conduit. 47 is a combustion chamber. Next, the operation will be explained.
先ず全体動作の説明を行うと、ガヌノズ)v38より供
給される燃料ガスの圧力Pcが燃料ガス圧力導管44に
よって下部密閉室32に導かれて第2 ・のゴム
ダイアフラム23を上方に持ち上げようと・し、燃焼空
気圧力PAが燃焼空気圧力導管45によって上部密閉室
30に導かれて第1のゴムダイアフラム22を下方に押
し下げようとする。その差圧に応じて圧力検出器2oに
出力が現れる。基準圧力室34には基準圧力として混合
部の負圧”PMが尊かれており、上部密閉室30と下部
密閉室32の共通の背圧PMを与えるようになっており
、混合部42の圧力PMが、ガスノズ/l/3Bの11
力Pcあるいは燃焼空気チャンバ40の圧力PA よ
りも常に低圧になっているため第1のコ゛ムダイアフラ
ム22、第2のコ゛ムダイアフラム23がノ又11云し
て動作不能におちいることはない。以」二の。l:うに
燃焼空気圧力PA、燃わガス圧力pcの/’<月を圧力
検出器で検出し、常にその差圧を一定に保って空気過剰
率を−・定に保つものである3、以上が実施例の概略動
作であるが次に本発明の骨イである圧力検出器20の動
作、特に周囲温度が変化したときの出力変動抑制機描に
ついて説明する。ある温度t。First, to explain the overall operation, the pressure Pc of the fuel gas supplied from the fuel gas pressure conduit 44 is guided into the lower sealed chamber 32 to lift the second rubber diaphragm 23 upward. However, the combustion air pressure PA is guided to the upper sealed chamber 30 by the combustion air pressure conduit 45 and tends to push the first rubber diaphragm 22 downward. An output appears on the pressure detector 2o in accordance with the differential pressure. The reference pressure chamber 34 uses the negative pressure PM of the mixing section as a reference pressure, and is designed to give a common back pressure PM to the upper sealed chamber 30 and the lower sealed chamber 32, so that the pressure of the mixing section 42 PM is 11 with gas nozzle/l/3B
Since the pressure is always lower than the pressure Pc or the pressure PA of the combustion air chamber 40, the first comb diaphragm 22 and the second comb diaphragm 23 will never become inoperable. It's second. l: Sea urchin combustion air pressure PA, combustion gas pressure pc /'< month is detected by a pressure detector, and the differential pressure is always kept constant to keep the excess air ratio -.3, or more. This is a general description of the operation of the embodiment.Next, the operation of the pressure detector 20, which is the essence of the present invention, will be described, particularly the mechanism for suppressing output fluctuations when the ambient temperature changes. At a certain temperature t.
のとき燃焼空気圧力PA、燃料ガス圧力POが等しく差
動1−ランスのコア28がコイ)v29に対して中心に
位置している状態に於て、Δt′C温度が上昇してt。When the combustion air pressure PA and the fuel gas pressure PO are equal and the core 28 of the differential lance is located in the center with respect to the coil (coil) v29, the temperature Δt'C rises to t.
十Δt℃になったとすると第1のゴムダイアフラム22
と第2のゴムダイヤフラム23は第2図で説明したよう
にその中心部が第3図においてそれぞれ下方及び上方に
移動しようとするが互いに打ち消し合って外部には現れ
ず、従ってコア28はその軸方向に変位することがなく
出力変化は現われない。次に温度が71°C降下してt
。If the temperature reaches 10Δt°C, the first rubber diaphragm 22
As explained in FIG. 2, the centers of the second rubber diaphragm 23 try to move downward and upward in FIG. 3, but they cancel each other out and do not appear on the outside. There is no displacement in the direction and no output change appears. Then the temperature dropped by 71°C and t
.
−Δt′Cになったとすると第1のゴムダイヤフラノ・
22と第2のゴムダイヤフラム23は第2図で説明した
ようにその中心部が第3図においてそれぞれ上方及び下
方に移動しようとするが互いに打ち消し合って外i′6
1には現れず、従ってコア28はその軸方向に変位する
ことがなく、出力変化は現れない。収斗の説明は、第3
図中22で示されるように、ゴムダイヤフラムの中心部
が外縁部より下っている場合の説明であるがその逆の場
合でも熱膨張、収縮にともなって発生する力は同様に打
ち消し合って゛外部には現れずコア28が軸方向に変位
することがなく、出力変化は生じない。以上の説明は変
位−電気信号変換部に差動トランスを用いた例であるが
これに限定されるものではない。-Δt'C, the first rubber diaphragm flannel
22 and the second rubber diaphragm 23, as explained in FIG. 2, their centers try to move upward and downward in FIG. 3, respectively, but they cancel each other out and move outward i'6.
1, therefore, the core 28 is not displaced in its axial direction, and no output change occurs. The explanation of Shuto is in Part 3.
As shown by 22 in the figure, the explanation is for the case where the center of the rubber diaphragm is lower than the outer edge, but even in the opposite case, the forces generated due to thermal expansion and contraction cancel each other out and are transferred to the outside. does not appear, the core 28 is not displaced in the axial direction, and no output change occurs. The above explanation is an example in which a differential transformer is used in the displacement-electrical signal converter, but the present invention is not limited to this.
発明の効果
本発明は、略同−形状の2個のllJ撓膜を同軸状態で
かつ軸方向に互いに逆向きにt’!!L!置し、それら
2個の可撓膜の外縁部は一定間隔を保った状態で固定さ
れており中心部は、可撓膜に作用する流体圧力によって
、一定間隔を保ったま寸軸方向に変位可能となっており
、その変イ☆量を電気量に変11力するように構成され
ている。周囲温度の変化に際して2個の可撓膜が熱膨張
収縮することに、1:ってひき起こされる軸方向の力が
、大きさ労しく向きが反対のだめ、内部で打ち消されて
外部に現ねず、出力の変化は生じない。すなわち月−カ
ー 出力化’r Pl−にi’il?1度依存性がない
という効果をイ]する。Effects of the Invention The present invention provides two llJ flexures having substantially the same shape in a coaxial state and in opposite directions in the axial direction t'! ! L! The outer edges of the two flexible membranes are fixed at a constant distance, and the center part can be displaced in the axial direction at a constant distance by fluid pressure acting on the flexible membranes. The structure is such that the variable quantity is converted into an electric quantity. The axial force caused by the thermal expansion and contraction of the two flexible membranes due to changes in ambient temperature is canceled out internally and is exerted externally due to the large size and opposite direction. Therefore, no change in output occurs. That is, I'il to output 'r Pl-? The effect of having no dependence is achieved once.
また、2個の可撓膜に作用する流体圧力P*、、 Pc
と、2個の可撓膜の共通背圧PMとの1yj係をPA)
PM、 PG) PM とすることによってPAと
PGの大きさの関係にかかわらず、すなわちPA −P
cの釦が11−負いずれであっても可撓膜が反転するこ
とがないという特有の効果を有する。In addition, the fluid pressures P*, Pc acting on the two flexible membranes are
and the common back pressure PM of the two flexible membranes, 1yj is PA)
PM, PG) By setting PM, regardless of the relationship between the sizes of PA and PG, that is, PA −P
It has a unique effect that the flexible membrane will not be reversed even if the button c is set to 11-negative.
第1図は従来例の断面図、第2図は第1図要部の動作説
明図、第3図は本発明一実施例の断面図である。
22.23・・・・・ゴムダイアフラム(可撓膜)、2
8・・・・・・コア、29・・・・・・コイIV、28
.29・・・・・・変位量−電気信号変換部。FIG. 1 is a sectional view of a conventional example, FIG. 2 is an explanatory diagram of the operation of the main part of FIG. 1, and FIG. 3 is a sectional view of an embodiment of the present invention. 22.23...Rubber diaphragm (flexible membrane), 2
8... Core, 29... Koi IV, 28
.. 29...Displacement amount-electrical signal converter.
Claims (2)
逆向きに配置し、それら2個の可撓膜の外縁部を一定間
隔を保って固定的に設け、中心部は一定間隔を保ったま
ま軸方向に俊位Tij能とし、前記2個の可撓膜の外面
に流体圧力を作用させて発位を発生させその発位−f1
tを″I−F気信号に変換する手段を具備してなる圧力
検出器。(1) Two flexible membranes with approximately the same shape are arranged coaxially and in opposite directions in the axial direction, and the outer edges of the two flexible membranes are fixedly provided with a constant interval, and the central part The two flexible membranes are allowed to move in the axial direction while maintaining a constant distance, and fluid pressure is applied to the outer surfaces of the two flexible membranes to generate a protrusion.
A pressure detector comprising means for converting t into an IF signal.
面に作用するいずれの圧力」、りも低い出力を作用させ
た特許請求の範囲第1項記載の圧力検出器。(2) The pressure sensor according to claim 1, wherein an output lower than "any pressure acting on both outer surfaces of the flexible membranes" is applied to the space sandwiched between the two flexible membranes. .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2790783A JPS59153140A (en) | 1983-02-22 | 1983-02-22 | Pressure detector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2790783A JPS59153140A (en) | 1983-02-22 | 1983-02-22 | Pressure detector |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS59153140A true JPS59153140A (en) | 1984-09-01 |
JPH0379655B2 JPH0379655B2 (en) | 1991-12-19 |
Family
ID=12233951
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2790783A Granted JPS59153140A (en) | 1983-02-22 | 1983-02-22 | Pressure detector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS59153140A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5652391A (en) * | 1995-05-12 | 1997-07-29 | Furon Company | Double-diaphragm gauge protector |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4331779Y1 (en) * | 1965-10-11 | 1968-12-24 | ||
JPS5018541U (en) * | 1973-06-14 | 1975-03-01 | ||
JPS5459186A (en) * | 1977-10-14 | 1979-05-12 | Bunker Ramo | Duplex pressure meter |
JPS5514851A (en) * | 1978-07-17 | 1980-02-01 | Fuji Electric Co Ltd | Method and apparatus for gas nitriding of stainles steel |
-
1983
- 1983-02-22 JP JP2790783A patent/JPS59153140A/en active Granted
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4331779Y1 (en) * | 1965-10-11 | 1968-12-24 | ||
JPS5018541U (en) * | 1973-06-14 | 1975-03-01 | ||
JPS5459186A (en) * | 1977-10-14 | 1979-05-12 | Bunker Ramo | Duplex pressure meter |
JPS5514851A (en) * | 1978-07-17 | 1980-02-01 | Fuji Electric Co Ltd | Method and apparatus for gas nitriding of stainles steel |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5652391A (en) * | 1995-05-12 | 1997-07-29 | Furon Company | Double-diaphragm gauge protector |
Also Published As
Publication number | Publication date |
---|---|
JPH0379655B2 (en) | 1991-12-19 |
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