JPH0441930B2 - - Google Patents
Info
- Publication number
- JPH0441930B2 JPH0441930B2 JP60174341A JP17434185A JPH0441930B2 JP H0441930 B2 JPH0441930 B2 JP H0441930B2 JP 60174341 A JP60174341 A JP 60174341A JP 17434185 A JP17434185 A JP 17434185A JP H0441930 B2 JPH0441930 B2 JP H0441930B2
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- resistor
- heat insulating
- air flow
- respect
- 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.)
- Expired - Lifetime
Links
- 238000010438 heat treatment Methods 0.000 claims description 19
- 239000012528 membrane Substances 0.000 claims description 19
- 239000000758 substrate Substances 0.000 claims description 2
- 230000001419 dependent effect Effects 0.000 description 16
- 230000007423 decrease Effects 0.000 description 7
- 239000011810 insulating material Substances 0.000 description 7
- 238000011144 upstream manufacturing Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 239000004642 Polyimide Substances 0.000 description 5
- 239000000853 adhesive Substances 0.000 description 5
- 230000001070 adhesive effect Effects 0.000 description 5
- 238000002485 combustion reaction Methods 0.000 description 5
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 5
- 229910052863 mullite Inorganic materials 0.000 description 5
- 229920001721 polyimide Polymers 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 239000012774 insulation material Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 230000020169 heat generation Effects 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 239000004020 conductor Substances 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 229920006015 heat resistant resin Polymers 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
Landscapes
- Measuring Volume Flow (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は膜式抵抗を有する直熱型流量センサ、
たとえば内燃機関の吸入空気量を検出するための
空気流量センサに関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a direct heating type flow sensor having a membrane resistor,
For example, the present invention relates to an air flow sensor for detecting the intake air amount of an internal combustion engine.
一般に、電子制御式内燃機関においては、基本
燃料噴射量、基本点火時期等の制御のために機関
の吸入空気量は重要な運転状態パラメータの１つ
である。従来、このような吸入空気量を検出する
ための空気流量センサ（エアフローメータとも言
う）はベーン式のものが主流であつたが、最近、
小型、応答性が良い等の利点を有する温度依存抵
抗を用いた熱式のものが実用化されている。
Generally, in an electronically controlled internal combustion engine, the intake air amount of the engine is one of the important operating state parameters for controlling the basic fuel injection amount, basic ignition timing, and the like. Conventionally, vane-type air flow sensors (also called air flow meters) have been the mainstream for detecting the amount of intake air, but recently,
A thermal type using a temperature-dependent resistor has been put into practical use, and has advantages such as small size and good response.
さらに、温度依存抵抗を有する空気流量センサ
としては、傍熱型と直熱型とがある。たとえば、
傍熱型の空気流量センサは、機関の吸気通路に設
けられた発熱抵抗、およびその上流、下流側に設
けられた２つの温度依存抵抗を備えている。この
場合、上流側の温度依存抵抗は発熱抵抗による加
熱前の空気流の温度を検出するものであり、つま
り、外気温度補償用であり、また、下流側の温度
依存抵抗は加熱抵抗によつて加熱された空気流の
温度を検出する。これにより、下流側の温度依存
抵抗と上流側の温度依存抵抗との温度差が一定に
なるように発熱抵抗の電流値をフイードバツク制
御し、発熱抵抗に印加される電圧により空気流量
（質量）を検出するものである。なお、上流側の
外気温度補償用温度依存抵抗を削除し、下流側の
温度依存抵抗の温度が一定になるように発熱抵抗
を制御すると、体積容量としての空気流量が検出
できる（参照：特公昭54−9662号公報）。他方、
傍熱型に比べて応答速度が早い直熱型の空気流量
センサは、機関の吸気通路に設けられた温度検出
兼用の発熱抵抗、およびその上流側に設けられた
温度依存抵抗を備えている。この場合、傍熱型と
同様に、上流側の温度依存抵抗は発熱抵抗による
加熱前の空気流の温度を検出するものであり、つ
まり、外気温度補償用である。これにより、発熱
抵抗とその上流側の温度依存抵抗との温度差が一
定になるように発熱抵抗の電流値をフイードバツ
ク制御し、発熱抵抗に印加される電圧により空気
流量（質量）を検出するものである。なお、この
場合にも、外気温度補償用温度依存抵抗を削除
し、発熱抵抗の温度が一定になるように発熱抵抗
を制御すると、体積容量としての空気流量が検出
できる。 Furthermore, there are two types of air flow rate sensors having temperature-dependent resistance: indirect heating type and direct heating type. for example,
The indirectly heated air flow sensor includes a heat generating resistor provided in the intake passage of the engine, and two temperature dependent resistors provided upstream and downstream thereof. In this case, the temperature-dependent resistance on the upstream side detects the temperature of the air flow before heating by the heating resistor, that is, it is for outdoor temperature compensation, and the temperature-dependent resistance on the downstream side detects the temperature of the air flow before heating by the heating resistor. Detects the temperature of the heated air stream. As a result, the current value of the heating resistor is feedback-controlled so that the temperature difference between the temperature-dependent resistance on the downstream side and the temperature-dependent resistance on the upstream side is constant, and the air flow rate (mass) is controlled by the voltage applied to the heating resistor. It is something to detect. Note that if you delete the temperature-dependent resistance for outdoor temperature compensation on the upstream side and control the heating resistor so that the temperature of the temperature-dependent resistance on the downstream side remains constant, the air flow rate as a volumetric capacity can be detected (reference: 54-9662). On the other hand,
A directly heated air flow sensor, which has a faster response speed than an indirectly heated type, includes a heat generating resistor that is provided in the intake passage of the engine and also serves as temperature detection, and a temperature dependent resistor that is provided upstream of the heat generating resistor. In this case, similarly to the indirect heating type, the upstream temperature-dependent resistance detects the temperature of the air flow before being heated by the heating resistor, that is, it is used to compensate for the outside air temperature. This allows feedback control of the current value of the heating resistor so that the temperature difference between the heating resistor and the temperature-dependent resistor upstream thereof remains constant, and detects the air flow rate (mass) based on the voltage applied to the heating resistor. It is. In this case as well, if the temperature-dependent resistance for compensating the outside air temperature is deleted and the heating resistor is controlled so that the temperature of the heating resistor is constant, the air flow rate as a volumetric capacity can be detected.
通常、発熱抵抗（膜式抵抗）の発熱温度と吸入
空気温度との差を一定値にするあるいは膜式抵抗
の発熱温度を一定にする空気流量センサの応答
性、ダイナミツクレンジは膜式抵抗を含む発熱部
兼温度検知部の熱容量（ヒートマス）と断熱効果
の程度で決定される。すなわち、最も応答性がよ
く、且つダイナミツクレンジを最も大きくするた
めには、膜式抵抗を含む発熱部兼温度検知部の質
量をできる限り小さくし、また、その部分を理想
的には完全に空気流中に浮かんだ状態にすること
である（参照：特願昭60−25232号）。 Normally, the responsiveness of an air flow sensor that keeps the difference between the heat generation temperature of a heat generation resistor (film type resistor) and the intake air temperature constant, or the heat generation temperature of a membrane type resistor, and the dynamic range uses a membrane type resistor. It is determined by the heat capacity (heat mass) of the heat generating part/temperature sensing part and the degree of insulation effect. In other words, in order to achieve the best response and the largest dynamic range, the mass of the heat generating part and temperature sensing part including the film resistor should be made as small as possible, and ideally that part should be completely removed. It is to make it float in the air flow (see Japanese Patent Application No. 60-25232).
しかしながら、通常、断熱部材は温度に対する
熱伝導率の変化が正特性もしくは負特性を有して
おり、従つて、空気流の温度により断熱部材の断
熱効果が変化し、この結果、センサの出力特性が
変化するという問題点がある。
However, the heat insulating member usually has a positive or negative characteristic in terms of change in thermal conductivity with respect to temperature. Therefore, the heat insulating effect of the heat insulating member changes depending on the temperature of the air flow, and as a result, the output characteristics of the sensor The problem is that it changes.
本発明の目的は、空気流の温度に対して出力特
性が変化しない直熱式流量センサを提供すること
にあり、その手段は、断熱部材を、温度に対する
熱伝導率の変化が正特性の部材と負特性の部材と
により構成したことである。
An object of the present invention is to provide a directly heated flow rate sensor whose output characteristics do not change with respect to the temperature of the air flow. and a member having negative characteristics.
上述の手段によれば、断熱部材の温度に対する
熱伝導率を一様（一定）にならしめたことがで
き、これにより、断熱部材の断熱効果は温度に対
して一様となる。
According to the above-mentioned means, it is possible to make the thermal conductivity of the heat insulating member uniform with respect to temperature, and thereby the heat insulating effect of the heat insulating member becomes uniform with respect to temperature.
以下、図面により本発明の実施例を説明する。 Embodiments of the present invention will be described below with reference to the drawings.
第３図は本発明に係る膜式抵抗を有する直熱型
空気流量センサが適用された内燃機関を示す全体
概要図である。第３図において、内燃機関１の吸
気通路２にはエアクリーナ３および整流格子４を
介して空気が吸入される。この空気通路２内に保
持部材（たとえばアルミニウム）５が設けられ、
そこに空気流量を計測するための発熱ヒータ兼用
温度依存抵抗（膜式抵抗）６が設けられている。
膜式抵抗６はフレキシブル配線７によつて、外気
温度補償を行う温度依存抵抗８と共に、ハイブリ
ツド基板に形成されたセンサ回路９に接続されて
いる。 FIG. 3 is an overall schematic diagram showing an internal combustion engine to which a directly heated air flow sensor having a membrane resistor according to the present invention is applied. In FIG. 3, air is taken into an intake passage 2 of an internal combustion engine 1 via an air cleaner 3 and a rectifying grid 4. As shown in FIG. A holding member (for example, aluminum) 5 is provided in this air passage 2,
A temperature dependent resistor (film type resistor) 6 which also serves as a heat generating heater is provided therein for measuring the air flow rate.
The film resistor 6 is connected by a flexible wiring 7 to a sensor circuit 9 formed on a hybrid substrate, together with a temperature-dependent resistor 8 for compensating for outside temperature.
センサ回路９は外気温度に対して膜式抵抗６の
温度が一定になるように該抵抗６の発熱量をフイ
ードバツク制御し、そのセンサ出力VQを制御回
路１０に供給する。制御回路１０はたとえばマイ
クロコンピユータによつて構成され、燃料噴射弁
１１の制御等行うものである。 The sensor circuit 9 performs feedback control on the amount of heat generated by the film resistor 6 so that the temperature of the film resistor 6 is constant with respect to the outside air temperature, and supplies the sensor output VQ to the control circuit 10. The control circuit 10 is composed of, for example, a microcomputer, and controls the fuel injection valve 11.
センサ回路９は、第４図に示すごとく、膜式抵
抗６、温度依存抵抗８とブリツジ回路を構成する
抵抗９１，９２、比較器９３、比較器９３の出力
によつて制御されるトランジスタ９４、電圧バツ
フア９５により構成される、つまり、空気流量が
増加して膜式抵抗６（この場合、サーミスタ）の
温度が低下し、この結果、膜式抵抗６の抵抗値が
下降してV1≦VRとなると、比較器９３の出力に
よつてトランジスタ９４の導電率が増加する。従
つて、膜式抵抗６の発熱量が増加し、同時に、ト
ランジスタ９４のコレクタ電位すなわち電圧バツ
フア９５の出力電圧VQは上昇する。逆に空気流
量が減少して膜式抵抗６の温度が上昇すると、膜
式抵抗６の抵抗値が増加してV1＞VRとなり、比
較器９３の出力によつてトランジスタ９４の導電
率が減少する。従つて、膜式抵抗６の発熱量が減
少し、同時に、電圧バツフア９５の出力電圧VQ
は低下する。このようにして膜式抵抗６の温度は
外気温度によつて定まる値になるようにフイード
バツク制御され、出力電圧VQは空気流量を示す
ことになる。 As shown in FIG. 4, the sensor circuit 9 includes a film resistor 6, a temperature-dependent resistor 8, resistors 91 and 92 forming a bridge circuit, a comparator 93, a transistor 94 controlled by the output of the comparator 93, In other words, the air flow rate increases and the temperature of the membrane resistor 6 (thermistor in this case) decreases, and as a result, the resistance value of the membrane resistor 6 decreases so that V 1 ≦V. When R , the output of comparator 93 increases the conductivity of transistor 94. Therefore, the amount of heat generated by the film resistor 6 increases, and at the same time, the collector potential of the transistor 94, that is, the output voltage VQ of the voltage buffer 95 increases. Conversely, when the air flow rate decreases and the temperature of the membrane resistor 6 rises, the resistance value of the membrane resistor 6 increases and becomes V 1 >V R , and the conductivity of the transistor 94 increases according to the output of the comparator 93. Decrease. Therefore, the amount of heat generated by the membrane resistor 6 decreases, and at the same time, the output voltage V Q of the voltage buffer 95 decreases.
decreases. In this way, the temperature of the membrane resistor 6 is feedback-controlled to a value determined by the outside air temperature, and the output voltage VQ indicates the air flow rate.
第５図は第３図の膜式抵抗６の近傍の拡大図、
第６図は第５図の−線断面図である。第５
図、第６図に示すように、膜式抵抗６において
は、その一端のみが断熱部材１２を介して保持部
材５に支持されている。なお、膜式抵抗６を両持
保持により保持部材６に固定すると、膜式抵抗６
が歪ゲージの作用し、従つて、膜式抵抗６の歪み
によりその出力変化を招くという欠点が生ずる。
上述の膜式抵抗６の片持保持はこのような歪ゲー
ジ作用を防止するものである。 FIG. 5 is an enlarged view of the vicinity of the membrane resistor 6 in FIG.
FIG. 6 is a sectional view taken along the line -- in FIG. 5. Fifth
As shown in FIG. 6, only one end of the membrane resistor 6 is supported by the holding member 5 via the heat insulating member 12. As shown in FIG. Note that when the membrane resistor 6 is fixed to the holding member 6 by holding both sides, the membrane resistor 6
This has the disadvantage that the film resistor 6 acts as a strain gauge, and therefore the distortion of the membrane resistor 6 causes a change in its output.
The above-mentioned cantilever holding of the membrane resistor 6 prevents such a strain gauge effect.
第７図は第５図のフレキシブル配線７の拡大
図、第８図は第７図の−線断面図である。第
７図、第８図に示すように、フレキシブル配線７
は、フレキシブルな絶縁樹脂フイルム７０１、パ
ターン形成された導体（たとえばCu）７０２ａ，
７０２ｂ、およびフレキシブルな絶縁樹脂フイル
ム７０３により構成されている。そして、接合部
Ａ，Ｂは膜式抵抗６のAuパツト部にたとえばAu
−Snの共晶によつて接合される。このように、
導体７０２ａ，７０２ｂはフレキシブルな絶縁樹
脂により覆われているので、ボンデイングワイヤ
に比較して、腐食、断線等に強い構造をなしてい
る。 FIG. 7 is an enlarged view of the flexible wiring 7 shown in FIG. 5, and FIG. 8 is a sectional view taken along the line -- in FIG. As shown in FIGS. 7 and 8, the flexible wiring 7
A flexible insulating resin film 701, a patterned conductor (for example, Cu) 702a,
702b and a flexible insulating resin film 703. Then, the junction parts A and B are connected to the Au part of the film resistor 6, for example, with Au.
- Bonded by Sn eutectic. in this way,
Since the conductors 702a and 702b are covered with a flexible insulating resin, they have a structure that is more resistant to corrosion and disconnection than bonding wires.
第１図は第６図の断熱部材１２の詳細な構造を
示す断面図である。第１図に示すように、断熱部
材１２は、接着剤（たとえばAu−Si共晶層）１
２１、ムライト断熱材１２２、接着剤（たとえば
耐熱樹脂接着剤）１２３、ポリイミド断熱材１２
４、および接着剤（たとえばハンダ）１２５の各
層からなる。ここで、第２図に示すように、ムラ
イト断熱材１２２は温度に対する熱伝導率の変化
が負特性を示し、ポリイミド断熱材１２４は温度
に対する熱伝導率の変化が正特性を示す。従つ
て、ムライト断熱材１２２の厚さおよびポリイミ
ド断熱材１２４の厚さを適切に設定すると、上記
正、負特性が相殺されて断熱部材１２全体として
温度に対する熱伝導率の変化を減少できることは
明らかである。 FIG. 1 is a sectional view showing the detailed structure of the heat insulating member 12 of FIG. 6. FIG. As shown in FIG.
21, Mullite insulation material 122, adhesive (for example, heat-resistant resin adhesive) 123, polyimide insulation material 12
4 and an adhesive (eg, solder) 125. Here, as shown in FIG. 2, the mullite heat insulating material 122 exhibits a negative change in thermal conductivity with respect to temperature, and the polyimide heat insulating material 124 exhibits a positive characteristic in a change in thermal conductivity with respect to temperature. Therefore, it is clear that by appropriately setting the thickness of the mullite insulation material 122 and the thickness of the polyimide insulation material 124, the positive and negative characteristics described above can be offset and the change in thermal conductivity with respect to temperature of the insulation member 12 as a whole can be reduced. It is.
このようにして、断熱部材１２の温度に対する
熱伝導率の変化を減少させ、理想的には、断熱部
材１２の温度に対する熱伝導率を一様（一定）に
することができる。 In this way, changes in the thermal conductivity of the heat insulating member 12 with respect to temperature can be reduced, and ideally, the thermal conductivity of the heat insulating member 12 with respect to temperature can be made uniform (constant).
なお、温度に対する熱伝導率の変化が負特性を
示す断熱材としては、ムライトの代りに、セラミ
ツク系、ガラス系の材料を用いることもでき、ま
た、温度に対する熱伝導率の変化が正特性を示す
断熱材としては、ポリイミドの代りに、樹脂系材
料を用いることもできる。さらに、第１図におい
ては、温度に対する熱伝導率の変化が正特性およ
び負特性の各材料を層上に結合せしめたが、これ
らの材料を混合せしめることも可能である。 Note that ceramic or glass-based materials can be used instead of mullite as heat insulating materials that exhibit negative thermal conductivity changes with temperature; As the heat insulating material shown, a resin material can also be used instead of polyimide. Further, in FIG. 1, materials having positive and negative thermal conductivity changes with respect to temperature are combined on a layer, but it is also possible to mix these materials.
以上説明したように本発明によれば、断熱部材
の温度に対する熱伝導率の変化を少なくでき、言
い換えると、断熱部材の温度に対する熱伝導率を
一様（一定）にすることができ、これにより、温
度変化が起きても膜式抵抗から断熱部材を通つて
保持部材へ逃げる熱の損失割合の変化を少なくで
きる。従つて、温度変化に対するセンサ出力変化
を小さくすることができる。
As explained above, according to the present invention, it is possible to reduce the change in thermal conductivity with respect to temperature of the heat insulating member, or in other words, it is possible to make the thermal conductivity of the heat insulating member with respect to temperature uniform (constant). Even if a temperature change occurs, it is possible to reduce the change in the loss rate of heat escaping from the membrane resistor to the holding member through the heat insulating member. Therefore, changes in sensor output due to temperature changes can be reduced.
第１図は本発明に係る直熱型流量センサの断熱
部材を示す断面図、第２図は第１図の断熱部材に
用いられる断熱材の温度に対する熱伝導率特性を
示すグラフ、第３図は本発明に係る膜式抵抗を有
する直熱型空気流量センサが適用された内燃機関
を示す全体概要図、第４図は第３図のセンサ回路
の回路図、第５図は第３図の膜式抵抗の近傍の拡
大図、第６図は第５図の−線断面図、第７図
は第５図のフレキシブル配線７の拡大図、第８図
は第７図の−線断面図である。
５……保持部材、６……膜式抵抗、７……フレ
キシブル配線、１２……断熱部材、１２１……接
着剤、１２２……ムライト断熱材、１２３……接
着剤、１２４……ポリイミド断熱材、１２５……
接着剤。
FIG. 1 is a cross-sectional view showing a heat insulating member of a directly heated flow rate sensor according to the present invention, FIG. 2 is a graph showing thermal conductivity characteristics with respect to temperature of the heat insulating material used in the heat insulating member of FIG. 1, and FIG. is an overall schematic diagram showing an internal combustion engine to which a directly heated air flow sensor having a membrane resistor according to the present invention is applied, FIG. 4 is a circuit diagram of the sensor circuit of FIG. 3, and FIG. 5 is a circuit diagram of the sensor circuit of FIG. 3. An enlarged view of the vicinity of the film resistor, FIG. 6 is a cross-sectional view taken along the line - in FIG. 5, FIG. 7 is an enlarged view of the flexible wiring 7 in FIG. be. 5... Holding member, 6... Film resistor, 7... Flexible wiring, 12... Heat insulating member, 121... Adhesive, 122... Mullite heat insulating material, 123... Adhesive, 124... Polyimide heat insulating material , 125...
glue.
Claims (1)
て保持部材に支持することにより収容した直熱型
流量センサにおいて、前記断熱部材を、温度に対
する熱伝導率の変化が正特性の部材と負特性の部
材とにより構成し、前記断熱部材の温度に対する
熱伝導率を一様にならしめたことを特徴とする直
熱型流量センサ。 ２ 前記正特性の部材と前記負特性の部材とを層
状にせしめた特許請求の範囲第１項に記載の直熱
型流量センサ。 ３ 前記正特性の部材と前記負特性の部材とを混
合せしめた特許請求の範囲第１項に記載の直熱型
流量センサ。[Scope of Claims] 1. A directly heated flow sensor in which a substrate on which a membrane resistor is formed is housed by being supported by a holding member via a heat insulating member, wherein the heat insulating member is arranged such that the thermal conductivity changes with respect to temperature. 1. A directly heated flow rate sensor comprising a member having a positive characteristic and a member having a negative characteristic, the heat insulating member having a uniform thermal conductivity with respect to temperature. 2. The direct heating type flow sensor according to claim 1, wherein the member with positive characteristics and the member with negative characteristics are layered. 3. The direct heating type flow sensor according to claim 1, wherein the member having the positive characteristic and the member having the negative characteristic are mixed.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60174341A JPS6235225A (en) | 1985-08-09 | 1985-08-09 | Direct heat type flow rate sensor |
| US06/894,895 US4756190A (en) | 1985-08-09 | 1986-08-08 | Direct-heated flow measuring apparatus having uniform characteristics |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60174341A JPS6235225A (en) | 1985-08-09 | 1985-08-09 | Direct heat type flow rate sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6235225A JPS6235225A (en) | 1987-02-16 |
| JPH0441930B2 true JPH0441930B2 (en) | 1992-07-09 |
Family
ID=15976943
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60174341A Granted JPS6235225A (en) | 1985-08-09 | 1985-08-09 | Direct heat type flow rate sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6235225A (en) |
-
1985
- 1985-08-09 JP JP60174341A patent/JPS6235225A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6235225A (en) | 1987-02-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4870860A (en) | Direct-heated flow measuring apparatus having improved response characteristics | |
| US4783996A (en) | Direct-heated flow measuring apparatus | |
| US4833912A (en) | Flow measuring apparatus | |
| US4843882A (en) | Direct-heated flow measuring apparatus having improved sensitivity response speed | |
| US4785662A (en) | Direct-heated gas-flow measuring apparatus | |
| JPS6122889B2 (en) | ||
| US6629456B2 (en) | Thermal flowmeter for detecting rate and direction of fluid flow | |
| US4735099A (en) | Direct-heated gas-flow measuring apparatus | |
| JPH0476415B2 (en) | ||
| JPS6140924B2 (en) | ||
| US4761995A (en) | Direct-heated flow measuring apparatus having improved sensitivity and response speed | |
| JPH11118566A (en) | Flow sensor | |
| JPH0441930B2 (en) | ||
| US4756190A (en) | Direct-heated flow measuring apparatus having uniform characteristics | |
| JPH0441932B2 (en) | ||
| JPH0476413B2 (en) | ||
| JPH0441931B2 (en) | ||
| JPS6053814A (en) | Airflow-rate measuring device | |
| JPS61186819A (en) | Directly heated flow rate sensor | |
| JPH0441933B2 (en) | ||
| JP2569733B2 (en) | Thermal air flow detector | |
| JPS6239722A (en) | Membrane type resistor for flow sensor | |
| JPH04147016A (en) | Thermal-type flow sensor | |
| JPH04122818A (en) | Heat-type flow sensor | |
| JPS60236023A (en) | Direct heating type air flow rate sensor |