JP2000304584A - Micro flow sensor - Google Patents
Micro flow sensorInfo
- Publication number
- JP2000304584A JP2000304584A JP11111043A JP11104399A JP2000304584A JP 2000304584 A JP2000304584 A JP 2000304584A JP 11111043 A JP11111043 A JP 11111043A JP 11104399 A JP11104399 A JP 11104399A JP 2000304584 A JP2000304584 A JP 2000304584A
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- sensor
- flow rate
- micro
- measured
- 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
- 239000012530 fluid Substances 0.000 claims abstract description 55
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 13
- 230000035945 sensitivity Effects 0.000 claims description 43
- 239000000463 material Substances 0.000 claims description 10
- 230000008542 thermal sensitivity Effects 0.000 abstract 1
- 238000005259 measurement Methods 0.000 description 13
- 238000004519 manufacturing process Methods 0.000 description 6
- 229920006395 saturated elastomer Polymers 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 102100032566 Carbonic anhydrase-related protein 10 Human genes 0.000 description 2
- 101000867836 Homo sapiens Carbonic anhydrase-related protein 10 Proteins 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 238000009529 body temperature measurement Methods 0.000 description 2
- 229910052796 boron Inorganic materials 0.000 description 2
- -1 boron ions Chemical class 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 102100033007 Carbonic anhydrase 14 Human genes 0.000 description 1
- 101000867862 Homo sapiens Carbonic anhydrase 14 Proteins 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Landscapes
- Measuring Volume Flow (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
Abstract
(57)【要約】
【課題】 本発明の目的は、小流量から大流量に亘る広
域の流量について的確な計測を可能にするマイクロフロ
ーセンサを提供することにある。
【解決手段】 計測対象流体の気流中に配設されるマイ
クロヒータ１２の上流側及び下流側のそれぞれに配置さ
れ、各組毎に熱感度が異なる少なくとも二組の対温度セ
ンサ１３，１４を備えてなることを特徴とするマイクロ
フローセンサ。
(57) [Problem] An object of the present invention is to provide a micro flow sensor capable of accurately measuring a wide flow rate from a small flow rate to a large flow rate. SOLUTION: At least two pairs of temperature sensors 13, 14 are arranged on the upstream side and the downstream side of a micro heater 12 arranged in the air flow of the fluid to be measured, and have different thermal sensitivities for each group. A micro flow sensor, comprising:
Description
【０００１】[0001]
【発明の属する技術分野】本発明は小流量から大流量に
亘る広域の流量について的確な計測を可能にするマイク
ロフローセンサに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a micro flow sensor capable of accurately measuring a wide flow rate from a small flow rate to a large flow rate.
【０００２】具体的には、１：１０００〜１：１０００
００のレンジアビリティを満足するマイクロフローセン
サを提案する。[0002] Specifically, 1: 1000 to 1: 1000
We propose a micro flow sensor that satisfies the range ability of 00.
【０００３】[0003]
【従来の技術】従来から知られているマイクロフローセ
ンサとしては、Ｓｉ（シリコン）をベースにした半導体
プロセスにより作製され、図５に示すようにダイアフラ
ム３１上にマイクロヒータ３２と温度センサとして用い
る一対のサーモパイル（以下、対サーモパイルと称す）
３３（３３ａ，３３ｂ）とを配置したものがある。2. Description of the Related Art A conventionally known micro flow sensor is manufactured by a semiconductor process based on Si (silicon), and a micro heater 32 and a pair used as a temperature sensor are provided on a diaphragm 31 as shown in FIG. Thermopile (hereinafter referred to as thermopile)
33 (33a, 33b).
【０００４】温度センサとしてはサーモパイルに限るも
のではなく、この他に、測温抵抗、サーミスタ、焦電体
などが用いられる。A temperature sensor is not limited to a thermopile, but may be a temperature measuring resistor, a thermistor, a pyroelectric body, or the like.
【０００５】このマイクロフローセンサにおいては、計
測対象流体（ガス等）の気流中でマイクロヒータ３２を
加熱し、マイクロヒータ３２の上流側に配置した一方の
サーモパイル３３ａの温度出力と、マイクロヒータ３２
の下流側に配置した他方のサーモパイル３３ｂの温度出
力との差から流速や流量を計測する原理が採用されてい
る。In this micro flow sensor, a micro heater 32 is heated in an air flow of a fluid to be measured (a gas or the like), and the temperature output of one thermopile 33a disposed upstream of the micro heater 32 and the micro heater 32
The principle of measuring the flow velocity or flow rate from the difference between the temperature output of the other thermopile 33b disposed downstream of the thermopile 33b is adopted.
【０００６】また、近年にあってはガスメータの小型化
が進み、単独のマイクロフローセンサで小流量から大流
量に亘る広域の流量について計測しようとする試みがな
されている。In recent years, the size of gas meters has been reduced, and attempts have been made to measure the flow rate in a wide range from a small flow rate to a large flow rate using a single micro flow sensor.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、かかる
従来のマイクロフローセンサにおいては、小流量から大
流量に亘る広域の流量について計測しようとしても、計
測対象流体の流量が大きい場合にはその計測時に出力の
飽和が生じてしまい現実的には計測が不可能であるとい
った問題がある。However, in such a conventional micro flow sensor, even if an attempt is made to measure a wide range of flow rate from a small flow rate to a large flow rate, if the flow rate of the fluid to be measured is large, an output is made during the measurement. There is a problem that the measurement is practically impossible due to the saturation of the data.
【０００８】より詳細に説明すると、計測対象流体の気
流が小流量にとどまっている場合には、計測対象気流か
らの熱移動量が小さいので、対サーモパイル３３（３３
ａ，３３ｂ）の温接点の温度は低く、計測対象流体との
温度差が大きい。従って、計測対象流体からの熱移動量
は計測対象流体の流速（流量）と比例し、的確な出力が
得られる。More specifically, when the air flow of the fluid to be measured remains at a small flow rate, the amount of heat transfer from the air flow to be measured is small.
The temperature of the hot junction of (a, 33b) is low, and the temperature difference with the fluid to be measured is large. Therefore, the amount of heat transfer from the fluid to be measured is proportional to the flow velocity (flow rate) of the fluid to be measured, and an accurate output can be obtained.
【０００９】これに対し、計測対象流体の気流が大流量
になった場合には、計測対象流体からの熱移動量が大き
いので、対サーモパイル３３（３３ａ，３３ｂ）の温接
点の温度は高くなり、計測対象流体との温度差が極めて
小さくなる。従って、出力の飽和を生じ、計測対象流体
からの熱移動量は計測対象流体の流速（流量）と比例し
なくなり、的確な出力が得られなくなってしまう。On the other hand, when the gas flow of the fluid to be measured has a large flow rate, the amount of heat transfer from the fluid to be measured is large, so that the temperature of the hot junction of the thermopile 33 (33a, 33b) becomes high. The temperature difference from the fluid to be measured becomes extremely small. Therefore, output saturation occurs, and the amount of heat transfer from the fluid to be measured is not proportional to the flow rate (flow rate) of the fluid to be measured, and an accurate output cannot be obtained.
【００１０】本発明は上記従来の欠点に着目し、これを
解決せんとしたものであり、その目的は、小流量から大
流量に亘る広域の流量について的確な計測を可能にする
マイクロフローセンサを提供することにある。SUMMARY OF THE INVENTION The present invention is directed to solving the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a micro flow sensor capable of accurately measuring a wide flow rate from a small flow rate to a large flow rate. To provide.
【００１１】[0011]
【課題を解決するための手段】請求項１に記載した本発
明のマイクロフローセンサは、計測対象流体の気流中に
配設されるマイクロヒータの上流側及び下流側のそれぞ
れに対称的に配置される２個の温度センサからなる対温
度センサを少なくとも二組備え、上記各対温度センサを
各組毎に上記マイクロヒータからの距離が各々異なるよ
うに配置してなることを特徴とする。According to the first aspect of the present invention, there is provided a micro flow sensor according to the present invention, which is symmetrically disposed on each of an upstream side and a downstream side of a micro heater disposed in an air flow of a fluid to be measured. At least two pairs of temperature sensors comprising two temperature sensors are provided, and the respective pairs of temperature sensors are arranged so that the distance from the micro heater is different for each group.
【００１２】請求項１に記載した本発明のマイクロフロ
ーセンサによれば、マイクロヒータに近い対温度センサ
が小流量の計測を、マイクロヒータに遠い対温度センサ
が大流量の計測をそれぞれ行うことにより、小流量から
大流量に亘る広域の流量について的確に計測することが
できる。According to the micro flow sensor of the present invention, the temperature sensor near the micro heater measures a small flow rate, and the temperature sensor far from the micro heater measures a large flow rate. Thus, it is possible to accurately measure the flow rate in a wide range from a small flow rate to a large flow rate.
【００１３】詳細には、マイクロヒータにより遠い対温
度センサは、上記計測対象流体が流体の拡散により冷や
されながら温度センサに到達するため、小流量の流量計
測は難しい。これに対し、マイクロヒータに近い対温度
センサは、温度センサ感温部の温度上昇が大きいため、
温度センサの温度感度範囲を超えてしまい、大流量の流
量計測が難しくなる。More specifically, the temperature sensor far from the micro-heater reaches the temperature sensor while the fluid to be measured is cooled by diffusion of the fluid, so that it is difficult to measure a small flow rate. On the other hand, the temperature sensor near the micro heater has a large temperature rise in the temperature sensor temperature sensing part.
The temperature exceeds the temperature sensitivity range of the temperature sensor, and it becomes difficult to measure a large flow rate.
【００１４】しかし、上記の二組の対温度センサを両方
配置することにより、各々を補完する形で小流量から大
流量までを計測できるようになる。However, by arranging both of the above two sets of temperature sensors, it becomes possible to measure from a small flow rate to a large flow rate in a complementary manner.
【００１５】請求項２に記載した本発明のマイクロフロ
ーセンサは、請求項１に記載のマイクロフローセンサに
おいて、上記少なくとも二組の対温度センサが、上記マ
イクロヒータに近い対温度センサほど、上記マイクロヒ
ータから離れた対温度センサよりも、上記計測対象流体
からの熱量に対する上記各対温度センサ感温部の温度上
昇感度が高い温度センサで構成されていることを特徴と
する。According to a second aspect of the present invention, there is provided the micro flow sensor according to the first aspect, wherein the at least two pairs of temperature sensors are arranged such that the closer the temperature sensor to the micro heater is, the more the micro temperature sensor becomes. It is characterized by comprising a temperature sensor having a higher temperature rise sensitivity of each of the temperature sensing portions for the temperature sensor with respect to the amount of heat from the fluid to be measured than the temperature sensor separated from the heater.
【００１６】請求項２に記載した本発明のマイクロフロ
ーセンサによれば、マイクロヒータからの距離差による
温度センサ感温部の温度上昇差と、計測対象流体からの
熱量に対する各対温度センサ感温部の温度上昇感度差と
の相乗効果により、より広域の流量計測が可能になる。According to the second aspect of the present invention, the temperature rise difference of the temperature sensor temperature sensing portion due to the difference in distance from the micro heater and the temperature sensor temperature sensitivity to the amount of heat from the fluid to be measured. Due to the synergistic effect with the temperature rise sensitivity difference of the section, the flow rate measurement in a wider area becomes possible.
【００１７】請求項３に記載した本発明のマイクロフロ
ーセンサは、計測対象流体の気流中に配設されるマイク
ロヒータの上流側及び下流側のそれぞれに対称的に配置
される２個の温度センサからなる対温度センサを少なく
とも二組備え、上記計測対象流体からの熱量に対する上
記各対温度センサの感温部の温度上昇感度を、各組毎に
各々異なる対温度センサを配置してなることを特徴とす
る。According to a third aspect of the present invention, there is provided a micro flow sensor comprising two temperature sensors disposed symmetrically on the upstream side and the downstream side of a micro heater disposed in an air flow of a fluid to be measured. Comprising at least two pairs of temperature sensors comprising: a temperature rise sensitivity of the temperature-sensitive portion of each of the temperature sensors with respect to the amount of heat from the fluid to be measured, wherein different temperature sensors are arranged for each group. Features.
【００１８】請求項３に記載した本発明のマイクロフロ
ーセンサによれば、計測対象流体からの熱量に対する各
対温度センサ感温部の温度上昇感度差を利用して、熱温
度上昇感度が高い対温度センサが小流量の計測を、熱温
度上昇感度が低い対温度センサが大流量の計測をそれぞ
れ行うことにより、小流量から大流量に亘る広域の流量
について的確に計測することができる。According to the micro flow sensor of the present invention, the difference in the temperature rise sensitivity of each temperature sensor temperature sensing portion with respect to the amount of heat from the fluid to be measured is utilized to make the heat flow sensitivity high. By measuring the small flow rate by the temperature sensor and measuring the large flow rate by the temperature sensor with low thermal temperature rise sensitivity, it is possible to accurately measure a wide flow rate from the small flow rate to the large flow rate.
【００１９】詳細には、マイクロヒータにより暖められ
た計測対象流体からの熱移動量が同じであっても、熱温
度上昇感度が高い場合、温度センサ感温部の温度は比較
的低流量で上記計測対象流体温度近くに達し、当然上記
計測対象流体温度よりも高い温度にはならずに出力が飽
和する。上記熱移動量が上記計測対象流体の流量に対し
て単調増加の関係があるので、熱温度上昇感度が低い対
温度センサの方が出力の飽和する流量が大きくなり、よ
り大流量の計測が可能になる。一方で、熱温度上昇感度
が高い場合、少しの熱移動量でもセンサ感度が発生する
ため、より小流量の計測が可能になる。More specifically, even if the heat transfer amount from the fluid to be measured heated by the micro-heater is the same, if the heat temperature rise sensitivity is high, the temperature of the temperature sensor temperature sensing part is relatively low and the flow rate is low. The output reaches the temperature of the fluid to be measured, and naturally the output is saturated without reaching a temperature higher than the temperature of the fluid to be measured. Since the amount of heat transfer has a monotonically increasing relationship with the flow rate of the fluid to be measured, the flow rate at which the temperature sensor with low thermal temperature rise sensitivity is lower than that of the temperature sensor at which the output saturates becomes larger, and a larger flow rate can be measured become. On the other hand, when the thermal temperature rise sensitivity is high, the sensor sensitivity is generated even with a small amount of heat transfer, so that a smaller flow rate can be measured.
【００２０】したがって上記の二組の対温度センサを両
方配置することにより、各々を補完する形で小流量から
大流量までを計測できるようになる。Therefore, by arranging both of the above two sets of temperature sensors, it becomes possible to measure from a small flow rate to a large flow rate in a form complementing each other.
【００２１】請求項４に記載した本発明のマイクロフロ
ーセンサは、請求項２又は３に記載のマイクロフローセ
ンサにおいて、上記少なくとも二組の対温度センサが、
それぞれ対温度センサ感温部の熱容量が各々異なるよう
に形成されていることを特徴とする。According to a fourth aspect of the present invention, there is provided the micro flow sensor according to the second or third aspect, wherein the at least two pairs of temperature sensors are:
It is characterized in that the heat capacities of the temperature sensing portions are different from each other.
【００２２】請求項４に記載した本発明のマイクロフロ
ーセンサによれば、同じ熱移動量に対し、熱容量が大き
いと熱温度上昇感度は小さくなり、温度センサ感温部の
温度上昇も鈍くなる一方、熱容量が小さいと熱温度上昇
感度は大きくなり、温度センサ感温部の温度上昇も鋭く
なる。According to the microflow sensor of the present invention, when the heat capacity is large for the same heat transfer amount, the sensitivity to heat temperature rise becomes small, and the temperature rise of the temperature sensor temperature sensing portion becomes slow. On the other hand, if the heat capacity is small, the temperature rise sensitivity becomes large, and the temperature rise of the temperature sensing portion becomes sharp.
【００２３】請求項５に記載した本発明のマイクロフロ
ーセンサは、請求項２〜４の何れかに記載のマイクロフ
ローセンサにおいて、上記少なくとも二組の対温度セン
サが、それぞれの対温度センサ感温部とセンサ基体との
熱抵抗を各々異なるように形成してなることを特徴とす
る。According to a fifth aspect of the present invention, there is provided the micro flow sensor according to any one of the second to fourth aspects, wherein the at least two pairs of temperature sensors are each a temperature sensor. It is characterized in that the thermal resistance of the part and the thermal resistance of the sensor base are different from each other.
【００２４】請求項５に記載した本発明のマイクロフロ
ーセンサによれば、同じ熱移動量に対し、温度センサ感
温部とセンサ基体との熱抵抗が小さいと、熱がすぐにセ
ンサ基体に伝導し、センサ基体はすぐにマイクロフロー
センサが取り付けられる筐体に熱を放出するため、熱温
度上昇感度は小さくなり、温度センサ感温部の温度上昇
も鈍くなる。According to the micro flow sensor of the present invention, if the thermal resistance between the temperature sensor temperature sensing portion and the sensor base is small for the same heat transfer amount, heat is immediately transferred to the sensor base. However, since the sensor base immediately emits heat to the housing in which the microflow sensor is mounted, the sensitivity to the increase in the heat temperature is reduced, and the temperature rise in the temperature sensor temperature sensing portion is also reduced.
【００２５】一方、同じ熱移動量に対し、温度センサ感
温部とセンサ基体との熱抵抗が大きいと、熱がなかなか
センサ基体に伝導されず、センサ基体がすぐにはマイク
ロフローセンサが取り付けられる筐体に熱を放出しない
ため、熱温度上昇感度は大きくなり、温度センサ感温部
の温度上昇も鋭くなる。On the other hand, if the thermal resistance between the temperature sensor temperature sensing portion and the sensor base is large for the same heat transfer amount, heat is not easily transmitted to the sensor base, and the microflow sensor is immediately attached to the sensor base. Since no heat is released to the housing, the temperature rise sensitivity is increased and the temperature rise of the temperature sensing part is also sharp.
【００２６】請求項６に記載した本発明のマイクロフロ
ーセンサは、請求項２〜５の何れかに記載のマイクロフ
ローセンサにおいて、上記少なくとも二組の対温度セン
サが、各組毎に異なる配線パターンで形成されているこ
とを特徴とする。According to a sixth aspect of the present invention, in the micro flow sensor according to any one of the second to fifth aspects, the at least two pairs of temperature sensors are different from each other in a wiring pattern. It is characterized by being formed by.
【００２７】請求項６に記載した本発明のマイクロフロ
ーセンサによれば、少なくとも二組の対温度センサを各
組毎に異なる配線パターンで形成することにより、結果
的に、各組の各対温度センサの上記マイクロヒータから
の距離を各々異ならせ、あるいは、計測対象流体からの
熱量に対する各対温度センサの感温部の温度上昇感度を
各々異ならせることとし、各組の対温度センサによって
小流量から大流量に亘る広域を細分化した各域毎の計測
を可能にしたので、小流量から大流量に亘る広域の流量
について的確に計測することができる。According to the micro flow sensor of the present invention, at least two pairs of temperature sensors are formed with different wiring patterns for each group, and consequently each temperature sensor of each group is formed. The distance between the sensor and the micro heater is varied, or the sensitivity of the temperature-sensitive part of each temperature sensor to the amount of heat from the fluid to be measured is varied. Since the measurement for each area obtained by subdividing the wide area from the large flow rate to the large flow rate is enabled, it is possible to accurately measure the flow rate in the wide area from the small flow rate to the large flow rate.
【００２８】尚、上述した請求項１〜６に記載の各マイ
クロフローセンサにおいては、各組の対温度センサを同
じ材質のものを採用する場合には、その製造工程の際に
同時に形成配置することができ、付加的な工程を強いら
れることがなく、効率よく製造することができる。In each of the micro flow sensors according to the first to sixth aspects of the present invention, when the same material is used for each set of temperature sensors, they are formed and arranged simultaneously during the manufacturing process. Therefore, it is possible to efficiently manufacture the apparatus without requiring additional steps.
【００２９】請求項７に記載した本発明のマイクロフロ
ーセンサは、請求項１〜６の何れかに記載のマイクロフ
ローセンサにおいて、上記少なくとも二組の対温度セン
サが、各組毎に異なる材質のものからなることを特徴と
する。According to a seventh aspect of the present invention, in the micro flow sensor according to any one of the first to sixth aspects, the at least two sets of temperature sensors are made of different materials for each set. It is characterized by consisting of
【００３０】請求項７に記載した本発明のマイクロフロ
ーセンサによれば、少なくとも二組の対温度センサを各
組毎に異なる材質のものとすることにより、結果的に、
各組の各対温度センサの上記マイクロヒータからの距離
を各々異ならせ、あるいは、計測対象流体からの熱量に
対する各対温度センサの感温部の温度上昇感度を各々異
ならせることとし、各組の対温度センサによって小流量
から大流量に亘る広域の流量について的確に計測するこ
とができる。According to the micro flow sensor of the present invention described in claim 7, at least two sets of temperature sensors are made of different materials for each set.
The distance from the micro heater of each pair of temperature sensors to the micro heater is different, or the temperature rise sensitivity of the temperature sensing part of each temperature sensor to the amount of heat from the fluid to be measured is different from each other. With the temperature sensor, it is possible to accurately measure the flow rate in a wide range from a small flow rate to a large flow rate.
【００３１】[0031]
【発明の実施の形態】以下、本発明の第１の実施形態を
添付図面に基づいて説明する。ここで、図１において、
（ａ）は本発明のマイクロフローセンサの第１の実施形
態を示す概略平面図であり、（ｂ）は図１（ａ）の概略
側面図である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings. Here, in FIG.
(A) is a schematic plan view showing a first embodiment of the microflow sensor of the present invention, and (b) is a schematic side view of FIG. 1 (a).
【００３２】図１に示すマイクロフローセンサは、ダイ
アフラム１１と、計測対象流体（ガス等）の気流中に配
設されかつダイアフラム１１上に配設されるマイクロヒ
ータ１２と、計測対象流体の気流方向Ｘにおいて上記マ
イクロヒータ１２の上流側及び下流側のそれぞれに対称
的に配設される二組の対サーモパイル１３（１３ａ，１
３ｂ），１４（１４ａ，１４ｂ）と、によって構成され
ており、各対サーモパイルは上記マイクロヒータ１２か
らの距離が各々異なるように配設されている。尚、ここ
では各組の対サーモパイル１３（１３ａ，１３ｂ），１
４（１４ａ，１４ｂ）は、それぞれ同じ材質のものであ
り、その製造工程の際に同時に形成配置することがで
き、付加的な工程を強いられることがなく、効率よく製
造することができるようになっている。The micro-flow sensor shown in FIG. 1 has a diaphragm 11, a micro-heater 12 provided in the air flow of a fluid to be measured (gas or the like) and provided on the diaphragm 11, a gas flow direction of the fluid to be measured. X, two pairs of thermopiles 13 (13a, 1a) symmetrically disposed on the upstream and downstream sides of the microheater 12, respectively.
3b) and 14 (14a and 14b), and each thermopile is arranged so that the distance from the micro heater 12 is different. Here, each pair of thermopiles 13 (13a, 13b), 1
4 (14a, 14b) are made of the same material, can be formed and arranged at the same time during the manufacturing process, and can be manufactured efficiently without requiring additional steps. Has become.
【００３３】一般にサーモパイルは、感温部となる温接
点群と基準温度感知部となる冷接点群を備えた温度セン
サであり、冷接点基準温度に対する感温部温度の温度差
が出力電圧となるセンサである。In general, a thermopile is a temperature sensor having a hot junction group serving as a temperature sensing portion and a cold junction group serving as a reference temperature sensing portion, and a temperature difference between the temperature of the temperature sensing portion and the reference temperature of the cold junction becomes an output voltage. It is a sensor.
【００３４】本実施形態で用いるサーモパイル１３ａ，
１３ｂ，１４ａ，１４ｂの冷接点群はＳｉからなるセン
サ基体となる肉厚部１１ａ，１１ａに配置されており、
基体はセンサを取り付ける筐体と非常に熱接触が良く配
置されるため、上記計測対象流体の温度となっている。The thermopile 13a used in this embodiment is
The cold junction groups 13b, 14a and 14b are arranged on the thick portions 11a and 11a serving as a sensor base made of Si.
Since the base is placed in very good thermal contact with the housing in which the sensor is mounted, the temperature of the base is the temperature of the fluid to be measured.
【００３５】一方、温接点群は断熱性の良い酸化膜で作
製されたダイアフラム１１上に配置され、マイクロヒー
タ１２で暖められた計測対象流体の温度と温接点群の温
度との差に比例した熱量が温接点に移動し、温接点群を
暖め、この温接点群と上記冷接点群との温度差が対サー
モパイル１３，１４の出力となる。On the other hand, the group of hot junctions is disposed on a diaphragm 11 made of an oxide film having good heat insulating properties, and is proportional to the difference between the temperature of the fluid to be measured heated by the microheater 12 and the temperature of the group of hot junctions. The amount of heat moves to the hot junction and heats the hot junction group, and the temperature difference between the hot junction group and the cold junction group becomes the output of the thermopiles 13 and 14.
【００３６】本実施形態で用いたサーモパイル１３ａ，
１３ｂ，１４ａ，１４ｂは、ボロンイオンを添加したＳ
ｉ配線とＡｌ配線とで作製された。The thermopile 13a used in this embodiment,
13b, 14a, and 14b are S to which boron ions are added.
It was made of an i wiring and an Al wiring.
【００３７】本実施形態では、サーモパイル１３ａ，１
３ｂ，１４ａ，１４ｂをマイクロヒータ１２の上流側及
び下流側にマイクロヒータ１２をはさんで対称に配置し
た対サーモパイル１３，１４を用いており、この対サー
モパイル１３，１４の上流側と下流側のサーモパイル出
力の出力差が計測対象流体の流量と単調増加の関係にあ
る事から、流量の計測が行われる。In the present embodiment, the thermopiles 13a, 1
Thermopiles 13 and 14 are used in which 3b, 14a and 14b are arranged symmetrically with the microheater 12 interposed between the upstream and downstream sides of the microheater 12, and the upstream and downstream sides of the thermopiles 13 and 14 are used. Since the output difference of the thermopile output is monotonically increasing with the flow rate of the fluid to be measured, the flow rate is measured.
【００３８】ダイアフラム１１の略中央に配置されたマ
イクロヒータ１２は、通常１０〜２０ミリ秒程度の矩形
パルス電圧または電流で駆動される。一定温度になるよ
うにフィードバック回路を用いて駆動される事もある。The micro-heater 12 disposed substantially at the center of the diaphragm 11 is driven by a rectangular pulse voltage or current of about 10 to 20 milliseconds. It may be driven using a feedback circuit so that the temperature becomes constant.
【００３９】マイクロヒータ１２に近い対サーモパイル
１３は、小流量でも上流側と下流側の温度差が現れやす
く、小流量の計測に用いられる。The thermopile 13 close to the microheater 12 tends to show a temperature difference between the upstream side and the downstream side even at a small flow rate, and is used for measuring a small flow rate.
【００４０】一方、マイクロヒータ１２から遠い対サー
モパイル１４は、流量がある程度大きくならないと温度
差が現れにくい反面、大流量の流量変化に対しては温度
差が変化しやすく、対流量の計測に用いられる。On the other hand, in the thermopile 14 far from the microheater 12, the temperature difference is unlikely to appear unless the flow rate is increased to some extent, but the temperature difference tends to change with a large flow rate change. Can be
【００４１】尚、マイクロヒータ１２と対サーモパイル
１３，１４との距離関係に変わりがない限り、図２
（ａ）に概略平面図で示し、同図（ｂ）に図２（ａ）の
Ａ−Ａ線断面図で示すように、基体１１の外形に対する
マイクロヒータ１２や対サーモパイル１３，１４の配置
に変化が生じても問題ない。As long as the distance relationship between the microheater 12 and the thermopiles 13 and 14 does not change, FIG.
As shown in a schematic plan view in FIG. 2A and a cross-sectional view taken along the line AA in FIG. There is no problem if a change occurs.
【００４２】図３には、本実施形態によって得られた流
量計測特性を示している。図３でも明らかなように、従
来の対サーモパイルが一組であるマイクロフローセンサ
に比べて、本発明のマイクロフローセンサは大流量にお
ける流量計測出力の飽和を回避することができ、小流量
から大流量までの流量計測が可能になった。FIG. 3 shows the flow rate measurement characteristics obtained by this embodiment. As is clear from FIG. 3, the micro flow sensor of the present invention can avoid the saturation of the flow measurement output at a large flow rate and can reduce the flow rate from a small flow rate to a large flow rate, as compared with a conventional micro flow sensor having a pair of thermopiles. Flow measurement up to the flow rate is now possible.
【００４３】次に、本発明の第２の実施形態を添付図面
に基づいて説明する。ここで、図４において、（ａ）は
本発明の第２の実施形態のマイクロフローセンサの一例
を示す概略平面図であり、（ｂ）は図４（ａ）のＢ−Ｂ
線断面図である。Next, a second embodiment of the present invention will be described with reference to the accompanying drawings. Here, in FIG. 4, (a) is a schematic plan view showing an example of the microflow sensor according to the second embodiment of the present invention, and (b) is BB in FIG. 4 (a).
It is a line sectional view.
【００４４】図４に示すマイクロフローセンサは、ダイ
アフラム１１と、計測対象流体の気流中でダイアフラム
１１の略中央に配設されるマイクロヒータ１２と、計測
対象流体の気流方向においてマイクロヒータ１２の上流
側及び下流側のそれぞれに対称的に配設される二組の対
サーモパイル１５，１６と、によって構成されており、
対サーモパイル１５の温接点は計測対象流体気流でマイ
クロヒータ１２の中央と同じ気流の位置に、対サーモパ
イル１６はその気流の両側でマイクロヒータ１２上の気
流上に、それぞれ配設される。The micro flow sensor shown in FIG. 4 has a diaphragm 11, a micro heater 12 disposed substantially at the center of the diaphragm 11 in the air flow of the fluid to be measured, and an upstream of the micro heater 12 in the air flow direction of the fluid to be measured. And two pairs of thermopiles 15, 16 symmetrically disposed on the side and the downstream side, respectively.
The hot junction of the thermopile 15 is disposed at the same airflow position as the center of the microheater 12 in the flow of the fluid to be measured, and the thermopile 16 is disposed on the airflow on the microheater 12 on both sides of the airflow.
【００４５】本実施形態で用いたサーモパイル１５ａ，
１５ｂ，１６ａ，１６ｂはすべて、ボロンイオンを添加
したＳｉ配線とＡｌ配線とで作製されており、その製造
工程の際に同時に作製することができ、付加的な工程を
強いられることがなく、効率よく製造することができる
ようになっている。The thermopile 15a used in this embodiment,
15b, 16a, and 16b are all made of Si wiring and Al wiring to which boron ions have been added, and can be manufactured at the same time during the manufacturing process. It can be manufactured well.
【００４６】本実施形態で用いるサーモパイル１５ａ，
１５ｂ，１６ａ，１６ｂの冷接点群はＳｉからなるセン
サ基体となる肉厚部に配置されており、基体１１ａ，１
１ａはセンサを取り付ける筐体と非常に熱接触が良く配
置されるため、上記計測対象流体の温度となっている。The thermopile 15a used in this embodiment is
The cold junction groups 15b, 16a, and 16b are arranged in a thick portion serving as a sensor base made of Si.
The temperature 1a is the temperature of the fluid to be measured because 1a is placed in very good thermal contact with the housing on which the sensor is mounted.
【００４７】一方、サーモパイル１５ａ，１５ｂ，１６
ａ，１６ｂの温接点群は断熱性の良い酸化膜で作製され
たダイアフラム１１上に配置され、マイクロヒータ１２
で暖められた計測対象流体の温度と温接点群の温度との
差に比例した熱量が温接点に移動し、温接点群を暖め、
この温接点群と上記冷接点群との温度差が対サーモパイ
ル１５，１６の出力となる。On the other hand, thermopiles 15a, 15b, 16
The hot junction groups a and 16b are arranged on a diaphragm 11 made of an oxide film having good heat insulating properties.
The amount of heat proportional to the difference between the temperature of the fluid to be measured and the temperature of the hot junction group moved to the hot junction and warms the hot junction group,
The temperature difference between the hot junction group and the cold junction group is the output of the thermopiles 15 and 16.
【００４８】本実施形態で、対サーモパイル１５と対サ
ーモパイル１６のそれぞれの温接点群と冷接点群との距
離が異なっており、この距離が温接点の熱が筐体へ伝導
される時の熱抵抗と比例関係があるため、対サーモパイ
ル１６の感温部に比べて、対サーモパイル１５の感温部
の、筐体との熱抵抗が大きくなる。In the present embodiment, the distance between the hot junction group and the cold junction group of the thermopile 15 and the thermopile 16 is different, and this distance is the heat generated when the heat of the hot junction is conducted to the housing. Since there is a proportional relationship with the resistance, the thermal resistance of the thermosensitive portion of the thermopile 15 to the housing is larger than that of the thermopile 16 to the thermopile.
【００４９】対サーモパイル１５の感温部は、筐体との
熱抵抗が大きく、小流量時の少量の熱量でも温度が上昇
するため、小流量計測の感度が良いが、温度が上がりや
すいため、大流量時の大きな熱量の時、感温部が暖めら
れた計測対象流体の温度に近くなり、大流量時の計測出
力が飽和してしまう。The temperature sensing portion of the thermopile 15 has a large thermal resistance with the housing and the temperature rises even with a small amount of heat when the flow rate is small. Therefore, the sensitivity of the small flow rate measurement is good, but the temperature tends to rise. At the time of a large amount of heat at the time of a large flow, the temperature sensing part approaches the temperature of the heated measurement target fluid, and the measurement output at the time of the large flow is saturated.
【００５０】一方、対サーモパイル１６の感温部は、筐
体との熱抵抗が小さいため、なかなか計測対象流体の温
度に近くならず、大流量の計測出力は飽和しにくいが、
感温部温度があがりにくいので、小流量時の計測は難し
い。On the other hand, the temperature sensing part of the thermopile 16 has a small thermal resistance with the housing, so that it does not easily approach the temperature of the fluid to be measured, and the measurement output of a large flow rate is hardly saturated.
It is difficult to measure at a small flow rate because the temperature of the temperature sensing part is hard to rise.
【００５１】上記二組の対サーモパイル出力を小流量時
と大流量時で自動または手動で切り替わる機構を備える
ことで、一つのマイクロフローセンサで小流量から大流
量までの広域の流量計測を的確に行えることが可能にな
った。By providing a mechanism for automatically or manually switching the two sets of thermopile outputs between a small flow rate and a large flow rate, a single microflow sensor can accurately measure a wide flow rate from a small flow rate to a large flow rate. Now you can do it.
【００５２】上記第２の実施形態においては、熱温度上
昇感度を二組の対温度センサで異なるように形成する手
法として、熱抵抗を配線長で変える方策を説明したが、
配線太さや配線材質を変更することで熱抵抗を変える方
策や、感温部の体積や材質を変更して感温部の熱容量を
変更してもよい。例えば、図４に示す実施形態において
は、対サーモパイル１５，１６の配線太さを変える方策
を行っている。In the second embodiment, a method of changing the thermal resistance by the wiring length has been described as a method of forming the thermal temperature rise sensitivity differently between the two sets of temperature sensors.
It is also possible to change the thermal resistance by changing the wiring thickness or the wiring material, or to change the heat capacity of the temperature-sensitive part by changing the volume or material of the temperature-sensitive part. For example, in the embodiment shown in FIG. 4, a measure is taken to change the wiring thickness of the thermopiles 15 and 16.
【００５３】上記第１及び第２の実施形態において、各
組の対温度センサとして対サーモパイル１３，１４、１
５，１６を採用した態様について説明したが、本発明は
この態様に限定されるものではなく、各組の温度センサ
として測温抵抗やサーミスタ、焦電体などの他の態様の
ものを採用することも可能である。In the first and second embodiments, thermopiles 13, 14, 1 are used as temperature sensors for each set.
Although the embodiments adopting the embodiments 5 and 16 have been described, the present invention is not limited to this embodiment, and adopts another embodiment such as a temperature measuring resistor, a thermistor, or a pyroelectric body as each set of temperature sensors. It is also possible.
【００５４】[0054]
【発明の効果】請求項１に記載した本発明のマイクロフ
ローセンサは、計測対象流体の気流中に配設されるマイ
クロヒータの上流側及び下流側のそれぞれに対称的に配
置される２個の温度センサからなる対温度センサを少な
くとも二組備え、上記各対温度センサを各組毎に上記マ
イクロヒータからの距離が各々異なるように配置してな
ることを特徴とする。According to the first aspect of the present invention, there is provided a micro flow sensor according to the first aspect of the present invention, wherein two symmetrically arranged upstream and downstream sides of a micro heater arranged in an air flow of a fluid to be measured are provided. At least two pairs of temperature sensors comprising temperature sensors are provided, and the respective pairs of temperature sensors are arranged so that the distance from the micro heater is different for each group.
【００５５】請求項１に記載した本発明のマイクロフロ
ーセンサによれば、マイクロヒータに近い対温度センサ
が小流量の計測を、マイクロヒータに遠い対温度センサ
が大流量の計測をそれぞれ行うことにより、小流量から
大流量に亘る広域の流量について的確に計測することが
できる。According to the micro flow sensor of the present invention, the temperature sensor near the micro heater measures a small flow rate, and the temperature sensor far from the micro heater measures a large flow rate. Thus, it is possible to accurately measure the flow rate in a wide range from a small flow rate to a large flow rate.
【００５６】詳細には、マイクロヒータにより遠い対温
度センサは、上記計測対象流体が流体の拡散により冷や
されながら温度センサに到達するため、小流量の流量計
測は難しい。これに対し、マイクロヒータに近い対温度
センサは、温度センサ感温部の温度上昇が大きいため、
温度センサの温度感度範囲を超えてしまい、大流量の流
量計測が難しくなる。In detail, the temperature sensor far from the micro heater reaches the temperature sensor while the fluid to be measured is cooled by diffusion of the fluid, so that it is difficult to measure a small flow rate. On the other hand, the temperature sensor near the micro heater has a large temperature rise in the temperature sensor temperature sensing part.
The temperature exceeds the temperature sensitivity range of the temperature sensor, and it becomes difficult to measure a large flow rate.
【００５７】しかし、上記の二組の対温度センサを両方
配置することにより、各々を補完する形で小流量から大
流量までを計測できるようになる。However, by arranging both of the two sets of temperature sensors, it is possible to measure from a small flow rate to a large flow rate in a manner that complements the two sets.
【００５８】請求項２に記載した本発明のマイクロフロ
ーセンサは、請求項１に記載のマイクロフローセンサに
おいて、上記少なくとも二組の対温度センサが、上記マ
イクロヒータに近い対温度センサほど、上記マイクロヒ
ータから離れた対温度センサよりも、上記計測対象流体
からの熱量に対する上記各対温度センサ感温部の温度上
昇感度が高い温度センサで構成されていることを特徴と
する。According to a second aspect of the present invention, there is provided the micro flow sensor according to the first aspect, wherein the at least two pairs of temperature sensors are arranged such that the closer the temperature sensor is to the micro heater, the more the micro temperature sensor becomes. It is characterized by comprising a temperature sensor having a higher temperature rise sensitivity of each of the temperature sensing portions for the temperature sensor with respect to the amount of heat from the fluid to be measured than the temperature sensor separated from the heater.
【００５９】請求項２に記載した本発明のマイクロフロ
ーセンサによれば、マイクロヒータからの距離差による
温度センサ感温部の温度上昇差と、計測対象流体からの
熱量に対する各対温度センサ感温部の温度上昇感度差と
の相乗効果により、より広域の流量計測が可能になる。According to the second aspect of the present invention, the temperature rise difference of the temperature sensor temperature sensing portion due to the difference in distance from the micro heater and the temperature sensor temperature sensing sensitivity to the amount of heat from the fluid to be measured. Due to the synergistic effect with the temperature rise sensitivity difference of the section, the flow rate measurement in a wider area becomes possible.
【００６０】請求項３に記載した本発明のマイクロフロ
ーセンサは、計測対象流体の気流中に配設されるマイク
ロヒータの上流側及び下流側のそれぞれに対称的に配置
される２個の温度センサからなる対温度センサを少なく
とも二組備え、上記計測対象流体からの熱量に対する上
記各対温度センサの感温部の温度上昇感度を、各組毎に
各々異なる対温度センサを配置してなることを特徴とす
る。According to a third aspect of the present invention, there is provided a micro flow sensor comprising two temperature sensors disposed symmetrically on the upstream side and the downstream side of a micro heater disposed in an air flow of a fluid to be measured. Comprising at least two pairs of temperature sensors comprising: a temperature rise sensitivity of the temperature-sensitive portion of each of the temperature sensors with respect to the amount of heat from the fluid to be measured, wherein different temperature sensors are arranged for each group. Features.
【００６１】請求項３に記載した本発明のマイクロフロ
ーセンサによれば、熱温度上昇感度が高い対温度センサ
が小流量の計測を、熱温度上昇感度が低い対温度センサ
が大流量の計測をそれぞれ行うことにより、小流量から
大流量に亘る広域の流量について的確に計測することが
できる。According to the microflow sensor of the present invention, the temperature sensor having a high thermal temperature rise sensitivity measures a small flow rate, and the temperature sensor having a low thermal temperature rise sensitivity measures a large flow rate. By performing each of them, it is possible to accurately measure a flow rate in a wide area from a small flow rate to a large flow rate.
【００６２】詳細には、マイクロヒータにより暖められ
た計測対象流体からの熱移動量が同じであっても、熱温
度上昇感度が高い場合、温度センサ感温部の温度は比較
的低流量で上記計測対象流体温度近くに達し、当然上記
計測対象流体温度よりも高い温度にはならずに出力が飽
和する。上記熱移動量が上記計測対象流体の流量に対し
て単調増加の関係があるので、熱温度上昇感度が低い対
温度センサの方が出力の飽和する流量が大きくなり、よ
り大流量の計測が可能になる。一方で、熱温度上昇感度
が高い場合、少しの熱移動量でもセンサ感度が発生する
ため、より小流量の計測が可能になる。More specifically, even if the amount of heat transfer from the fluid to be measured heated by the micro-heater is the same, if the heat temperature rise sensitivity is high, the temperature of the temperature sensor temperature sensing part is relatively low and the flow rate is low. The output reaches the temperature of the fluid to be measured, and naturally the output is saturated without reaching a temperature higher than the temperature of the fluid to be measured. Since the amount of heat transfer has a monotonically increasing relationship with the flow rate of the fluid to be measured, the flow rate at which the temperature sensor with low thermal temperature rise sensitivity is lower than that of the temperature sensor at which the output saturates becomes larger, and a larger flow rate can be measured become. On the other hand, when the thermal temperature rise sensitivity is high, the sensor sensitivity is generated even with a small amount of heat transfer, so that a smaller flow rate can be measured.
【００６３】したがって上記の二組の対温度センサを両
方配置することにより、各々を補完する形で小流量から
大流量までを計測できるようになる。Therefore, by arranging both of the above two sets of temperature sensors, it becomes possible to measure from a small flow rate to a large flow rate in a form complementing each other.
【００６４】請求項４に記載した本発明のマイクロフロ
ーセンサは、請求項２又は３に記載のマイクロフローセ
ンサにおいて、上記少なくとも二組の対温度センサが、
それぞれ対温度センサ感温部の熱容量が各々異なるよう
に形成されていることを特徴とする。According to a fourth aspect of the present invention, there is provided the micro flow sensor according to the second or third aspect, wherein the at least two sets of temperature sensors are:
It is characterized in that the heat capacities of the temperature sensing portions are different from each other.
【００６５】請求項４に記載した本発明のマイクロフロ
ーセンサによれば、同じ熱移動量に対し、熱容量が大き
いと熱温度上昇感度は小さくなり、温度センサ感温部の
温度上昇も鈍くなる一方、熱容量が小さいと熱温度上昇
感度は大きくなり、温度センサ感温部の温度上昇も鋭く
なる。According to the microflow sensor of the present invention, when the heat capacity is large with respect to the same heat transfer amount, the sensitivity to heat temperature rise decreases, and the temperature rise in the temperature sensor temperature sensing portion also decreases. On the other hand, if the heat capacity is small, the temperature rise sensitivity becomes large, and the temperature rise of the temperature sensing portion becomes sharp.
【００６６】したがって、熱温度上昇感度が小さく温度
センサ感温部の温度上昇が鈍い対温度センサにより大流
量の計測を行い、熱温度上昇感度が大きく温度センサ感
温部の温度上昇が鋭い対温度センサにより小流量の計測
を行うことにより、小流量から大流量に亘る広域の流量
について的確に計測することができる。Therefore, a large flow rate is measured by a temperature sensor having a small temperature rise sensitivity and a low temperature rise in the temperature sensor temperature sensitive section, and a large temperature measurement is provided by the temperature rise section having a large thermal temperature rise sensitivity and a sharp temperature rise in the temperature sensor temperature sensitive section. By measuring the small flow rate using the sensor, it is possible to accurately measure a wide flow rate from the small flow rate to the large flow rate.
【００６７】請求項５に記載した本発明のマイクロフロ
ーセンサは、請求項２〜４の何れかに記載のマイクロフ
ローセンサにおいて、上記少なくとも二組の対温度セン
サが、それぞれの対温度センサ感温部とセンサ基体との
熱抵抗を各々異なるように形成してなることを特徴とす
る。According to a fifth aspect of the present invention, there is provided the micro flow sensor according to any one of the second to fourth aspects, wherein the at least two sets of temperature sensors are each a temperature sensor. It is characterized in that the thermal resistance of the part and the thermal resistance of the sensor base are different from each other.
【００６８】請求項５に記載した本発明のマイクロフロ
ーセンサによれば、同じ熱移動量に対し、温度センサ感
温部とセンサ基体との熱抵抗が小さいと、熱がすぐにセ
ンサ基体に伝導し、センサ基体はすぐにマイクロフロー
センサが取り付けられる筐体に熱を放出するため、熱温
度上昇感度は小さくなり、温度センサ感温部の温度上昇
も鈍くなる。According to the micro flow sensor of the present invention, if the thermal resistance between the temperature sensor temperature sensing portion and the sensor base is small for the same heat transfer amount, heat is immediately transferred to the sensor base. However, since the sensor base immediately emits heat to the housing in which the microflow sensor is mounted, the sensitivity to the increase in the heat temperature is reduced, and the temperature rise in the temperature sensor temperature sensing portion is also reduced.
【００６９】一方、同じ熱移動量に対し、温度センサ感
温部とセンサ基体との熱抵抗が大きいと、熱がなかなか
センサ基体に伝導されず、センサ基体がすぐにはマイク
ロフローセンサが取り付けられる筐体に熱を放出しない
ため、熱温度上昇感度は大きくなり、温度センサ感温部
の温度上昇も鋭くなる。On the other hand, if the thermal resistance between the temperature sensor temperature sensing portion and the sensor base is large for the same heat transfer amount, heat is not easily transmitted to the sensor base, and the microflow sensor is immediately attached to the sensor base. Since no heat is released to the housing, the temperature rise sensitivity is increased and the temperature rise of the temperature sensing part is also sharp.
【００７０】したがって、熱温度上昇感度が小さく温度
センサ感温部の温度上昇が鈍い対温度センサにより大流
量の計測を行い、熱温度上昇感度が大きく温度センサ感
温部の温度上昇が鋭い対温度センサにより小流量の計測
を行うことにより、小流量から大流量に亘る広域の流量
について的確に計測することができる。Therefore, a large flow rate is measured by a temperature sensor having a small temperature rise sensitivity and a low temperature rise in the temperature sensor temperature sensitive portion, and a large temperature measurement is performed by the temperature sensor having a large heat temperature rise sensitivity and a sharp temperature rise in the temperature sensor temperature sensitive portion. By measuring the small flow rate using the sensor, it is possible to accurately measure a wide flow rate from the small flow rate to the large flow rate.
【００７１】請求項６に記載した本発明のマイクロフロ
ーセンサは、請求項２〜５の何れかに記載のマイクロフ
ローセンサにおいて、上記少なくとも二組の対温度セン
サが、各組毎に異なる配線パターンで形成されているこ
とを特徴とする。According to a sixth aspect of the present invention, in the micro flow sensor according to any one of the second to fifth aspects, the at least two pairs of temperature sensors have different wiring patterns for each pair. It is characterized by being formed by.
【００７２】請求項６に記載した本発明のマイクロフロ
ーセンサによれば、少なくとも二組の対温度センサを各
組毎に異なる配線パターンで形成することにより、結果
的に、各組の各対温度センサの上記マイクロヒータから
の距離を各々異ならせ、あるいは、計測対象流体からの
熱量に対する各対温度センサの感温部の温度上昇感度を
各々異ならせることとし、各組の対温度センサによって
小流量から大流量に亘る広域を細分化した各域毎の計測
を可能にしたので、小流量から大流量に亘る広域の流量
について的確に計測することができる。According to the micro flow sensor of the present invention, at least two pairs of temperature sensors are formed with different wiring patterns for each group, and consequently each temperature sensor of each group is formed. The distance between the sensor and the micro heater is varied, or the sensitivity of the temperature-sensitive part of each temperature sensor to the amount of heat from the fluid to be measured is varied. Since the measurement for each area obtained by subdividing the wide area from the large flow rate to the large flow rate is enabled, it is possible to accurately measure the flow rate in the wide area from the small flow rate to the large flow rate.
【００７３】尚、上述した請求項１〜６に記載の各マイ
クロフローセンサにおいては、各組の対温度センサを同
じ材質のものを採用する場合には、その製造工程の際に
同時に形成配置することができ、付加的な工程を強いら
れることがなく、効率よく製造することができる。In each of the micro flow sensors according to the first to sixth aspects of the present invention, when each set of temperature sensors is made of the same material, it is formed and arranged at the same time during the manufacturing process. Therefore, it is possible to efficiently manufacture the apparatus without requiring additional steps.
【００７４】請求項７に記載した本発明のマイクロフロ
ーセンサは、請求項１〜６の何れかに記載のマイクロフ
ローセンサにおいて、上記少なくとも二組の対温度セン
サが、各組毎に異なる材質のものからなることを特徴と
する。According to a seventh aspect of the present invention, in the micro flow sensor according to any one of the first to sixth aspects, the at least two sets of temperature sensors are made of different materials for each set. It is characterized by consisting of
【００７５】請求項７に記載した本発明のマイクロフロ
ーセンサによれば、少なくとも二組の対温度センサを各
組毎に異なる材質のものとすることにより、結果的に、
各組の各対温度センサの上記マイクロヒータからの距離
を各々異ならせ、あるいは、計測対象流体からの熱量に
対する各対温度センサの感温部の温度上昇感度を各々異
ならせることとし、各組の対温度センサによって小流量
から大流量に亘る広域の流量について的確に計測するこ
とができる。According to the microflow sensor of the present invention, at least two sets of temperature sensors are made of different materials for each set, and as a result,
The distance from the micro heater of each pair of temperature sensors to the micro heater is different, or the temperature rise sensitivity of the temperature sensing part of each temperature sensor to the amount of heat from the fluid to be measured is different from each other. With the temperature sensor, it is possible to accurately measure the flow rate in a wide range from a small flow rate to a large flow rate.
【図１】（ａ）は本発明の第１実施形態に係るマイクロ
フローセンサの一例を示す概略平面図であり、（ｂ）は
図１（ａ）の概略側面図である。FIG. 1A is a schematic plan view showing an example of a micro flow sensor according to a first embodiment of the present invention, and FIG. 1B is a schematic side view of FIG. 1A.
【図２】（ａ）は本発明の第１実施形態に係るマイクロ
フローセンサの他の例を示す概略平面図であり、（ｂ）
は図２（ａ）のＡ−Ａ線断面図である。FIG. 2A is a schematic plan view showing another example of the micro flow sensor according to the first embodiment of the present invention, and FIG.
FIG. 3 is a sectional view taken along line AA of FIG.
【図３】従来のマイクロフローセンサの出力結果と、本
発明のマイクロフローセンサの出力結果とを比較して示
すグラフである。FIG. 3 is a graph showing a comparison between an output result of a conventional micro flow sensor and an output result of a micro flow sensor of the present invention.
【図４】（ａ）は本発明の第２実施形態に係るマイクロ
フローセンサの一例を示す概略平面図であり、（ｂ）は
図４（ａ）のＢ−Ｂ線断面図である。FIG. 4A is a schematic plan view illustrating an example of a microflow sensor according to a second embodiment of the present invention, and FIG. 4B is a cross-sectional view taken along line BB of FIG. 4A.
【図５】従来のマイクロフローセンサを示す概略平面図
である。FIG. 5 is a schematic plan view showing a conventional micro flow sensor.
１１ ダイアフラム １２ マイクロヒータ １３，１４，１５，１６ 対サーモパイル 11 Diaphragm 12 Micro heater 13, 14, 15, 16 Thermopile
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ テーマコート゛(参考） Ｈ０１Ｌ 37/02 Ｈ０１Ｌ 37/02 Ｆターム(参考） 2F030 CA10 CB03 CC11 2F035 EA05 EA08 2G040 AB05 AB08 BA23 CA01 CA10 CA14 CA22 CB02 CB04 DA02 DA03 DA12 DA15 DA21 EA02 EA11 EA13 EB02 GA05 GA07 HA07 HA16 ZA05 ──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme coat ゛ (Reference) H01L 37/02 H01L 37/02 F term (Reference) 2F030 CA10 CB03 CC11 2F035 EA05 EA08 2G040 AB05 AB08 BA23 CA01 CA10 CA14 CA22 CB02 CB04 DA02 DA03 DA12 DA15 DA21 EA02 EA11 EA13 EB02 GA05 GA07 HA07 HA16 ZA05
Claims (7)
クロヒータの上流側及び下流側のそれぞれに対称的に配
置される２個の温度センサからなる対温度センサを少な
くとも二組備え、上記各対温度センサを各組毎に上記マ
イクロヒータからの距離が各々異なるように配置してな
ることを特徴とするマイクロフローセンサ。1. At least two pairs of temperature sensors comprising two temperature sensors symmetrically arranged on the upstream side and the downstream side of a micro heater disposed in an air flow of a fluid to be measured, respectively. A micro flow sensor, wherein each temperature sensor is arranged so that the distance from the micro heater is different for each set.
上記マイクロヒータに近い対温度センサほど、上記マイ
クロヒータから離れた対温度センサよりも、上記計測対
象流体からの熱量に対する上記各対温度センサ感温部の
温度上昇感度が高い温度センサで構成されていることを
特徴とする請求項１に記載のマイクロフローセンサ。2. The at least two sets of temperature sensors,
The temperature sensor closer to the micro-heater is configured by a temperature sensor having a higher temperature rise sensitivity of each of the temperature-sensitive portions to the amount of heat from the fluid to be measured than the temperature sensor far from the micro-heater. The micro flow sensor according to claim 1, wherein
クロヒータの上流側及び下流側のそれぞれに対称的に配
置される２個の温度センサからなる対温度センサを少な
くとも二組備え、上記計測対象流体からの熱量に対する
上記各対温度センサの感温部の温度上昇感度を、各組毎
に各々異なる対温度センサを配置してなることを特徴と
するマイクロフローセンサ。3. At least two pairs of temperature sensors comprising two temperature sensors symmetrically arranged on the upstream side and the downstream side of the micro heater arranged in the gas flow of the fluid to be measured, respectively. A micro flow sensor, wherein different temperature sensors are arranged for each set, with respect to the temperature rise sensitivity of the temperature sensor of each of the temperature sensors with respect to the amount of heat from the fluid to be measured.
それぞれ対温度センサ感温部の熱容量が各々異なるよう
に形成されていることを特徴とする請求項２又は３記載
のマイクロフローセンサ。4. The at least two sets of temperature sensors,
4. The micro flow sensor according to claim 2, wherein the heat capacities of the temperature sensing portions of the temperature sensor are different from each other.
それぞれの対温度センサ感温部とセンサ基体との熱抵抗
を各々異なるように形成してなることを特徴とする請求
項２〜４の何れかに記載のマイクロフローセンサ。5. The at least two sets of temperature sensors,
The microflow sensor according to any one of claims 2 to 4, wherein thermal resistances of the temperature sensing part of each temperature sensor and the sensor base are different from each other.
各組毎に異なる配線パターンで形成されていることを特
徴とする請求項２〜５の何れかに記載のマイクロフロー
センサ。6. The at least two sets of temperature sensors,
The micro flow sensor according to any one of claims 2 to 5, wherein a different wiring pattern is formed for each set.
各組毎に異なる材質のものからなることを特徴とする請
求項１〜６の何れかに記載のマイクロフローセンサ。7. The at least two sets of temperature sensors,
The microflow sensor according to any one of claims 1 to 6, wherein each group is made of a different material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11104399A JP3470881B2 (en) | 1999-04-19 | 1999-04-19 | Micro flow sensor |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11104399A JP3470881B2 (en) | 1999-04-19 | 1999-04-19 | Micro flow sensor |
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|---|---|
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| JP3470881B2 JP3470881B2 (en) | 2003-11-25 |
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ID=14550974
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|---|---|---|---|
| JP11104399A Expired - Fee Related JP3470881B2 (en) | 1999-04-19 | 1999-04-19 | Micro flow sensor |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006017724A (en) * | 2004-06-30 | 2006-01-19 | Codman & Shurtleff Inc | Thermal flow sensor with asymmetric design |
| KR100556059B1 (en) * | 2003-07-02 | 2006-03-03 | 정완영 | Fluid flow detection device |
| WO2007110934A1 (en) * | 2006-03-28 | 2007-10-04 | Shimadzu Corporation | Thermal mass flow rate meter |
| JP2007279036A (en) * | 2006-03-31 | 2007-10-25 | Sensirion Ag | Flow sensor with thermocouple |
| WO2013030198A1 (en) * | 2011-08-31 | 2013-03-07 | Hahn-Schickard-Gesellschaft für angewandte Forschung e.V. | Flow sensor for determining a flow parameter and method for determining said flow parameter |
| US9224658B2 (en) | 2013-01-31 | 2015-12-29 | Sensirion Ag | Membrane-based sensor device with non-dielectric etch-stop layer around substrate recess |
| CN106017587A (en) * | 2016-05-12 | 2016-10-12 | 北京启芯传感科技有限公司 | Hollow hot-film type flow sensor and manufacturing and integrating method thereof |
| JP2018141664A (en) * | 2017-02-27 | 2018-09-13 | アズビル株式会社 | Flow sensor |
| US10094691B2 (en) | 2014-12-22 | 2018-10-09 | Sensirion Ag | Flow sensor arrangement |
| WO2019078087A1 (en) * | 2017-10-20 | 2019-04-25 | オムロン株式会社 | Flow sensor |
| WO2021260987A1 (en) * | 2020-06-22 | 2021-12-30 | 日立Astemo株式会社 | Thermal flow rate sensor |
| CN114838775A (en) * | 2022-05-17 | 2022-08-02 | 东南大学 | Multi-range thermal gas flow sensor |
| CN118583914A (en) * | 2024-08-01 | 2024-09-03 | 苏州芯镁信电子科技有限公司 | A thermal conductivity gas sensor, preparation method and gas thermal conductivity detection method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000206134A (en) | 1999-01-11 | 2000-07-28 | Tokyo Gas Co Ltd | Hot wire flow sensor |
-
1999
- 1999-04-19 JP JP11104399A patent/JP3470881B2/en not_active Expired - Fee Related
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100556059B1 (en) * | 2003-07-02 | 2006-03-03 | 정완영 | Fluid flow detection device |
| JP2006017724A (en) * | 2004-06-30 | 2006-01-19 | Codman & Shurtleff Inc | Thermal flow sensor with asymmetric design |
| WO2007110934A1 (en) * | 2006-03-28 | 2007-10-04 | Shimadzu Corporation | Thermal mass flow rate meter |
| US7895888B2 (en) | 2006-03-28 | 2011-03-01 | Shimadzu Corporation | Thermal mass flow meter including heating element and temperature sensors formed on separate chips and secured to the outer periphery of the pipe |
| JP4962489B2 (en) * | 2006-03-28 | 2012-06-27 | 株式会社島津製作所 | Thermal mass flow meter |
| JP2007279036A (en) * | 2006-03-31 | 2007-10-25 | Sensirion Ag | Flow sensor with thermocouple |
| EP2869039A1 (en) * | 2011-08-31 | 2015-05-06 | Hahn-Schickard-Gesellschaft für angewandte Forschung e.V. | Flow sensor for monitoring a flow parameter and method of determining the same |
| EP2869040A1 (en) * | 2011-08-31 | 2015-05-06 | Hahn-Schickard-Gesellschaft für angewandte Forschung e.V. | Flow sensor for monitoring a flow parameter and method of determining the same |
| WO2013030198A1 (en) * | 2011-08-31 | 2013-03-07 | Hahn-Schickard-Gesellschaft für angewandte Forschung e.V. | Flow sensor for determining a flow parameter and method for determining said flow parameter |
| EP2869041A1 (en) * | 2011-08-31 | 2015-05-06 | Hahn-Schickard-Gesellschaft für angewandte Forschung e.V. | Flow sensor for monitoring a flow parameter and method of determining the same |
| US9224658B2 (en) | 2013-01-31 | 2015-12-29 | Sensirion Ag | Membrane-based sensor device with non-dielectric etch-stop layer around substrate recess |
| US10094691B2 (en) | 2014-12-22 | 2018-10-09 | Sensirion Ag | Flow sensor arrangement |
| CN106017587A (en) * | 2016-05-12 | 2016-10-12 | 北京启芯传感科技有限公司 | Hollow hot-film type flow sensor and manufacturing and integrating method thereof |
| JP2018141664A (en) * | 2017-02-27 | 2018-09-13 | アズビル株式会社 | Flow sensor |
| WO2019078087A1 (en) * | 2017-10-20 | 2019-04-25 | オムロン株式会社 | Flow sensor |
| WO2021260987A1 (en) * | 2020-06-22 | 2021-12-30 | 日立Astemo株式会社 | Thermal flow rate sensor |
| CN114838775A (en) * | 2022-05-17 | 2022-08-02 | 东南大学 | Multi-range thermal gas flow sensor |
| CN118583914A (en) * | 2024-08-01 | 2024-09-03 | 苏州芯镁信电子科技有限公司 | A thermal conductivity gas sensor, preparation method and gas thermal conductivity detection method |
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