JP5223708B2

JP5223708B2 - Air flow measurement device

Info

Publication number: JP5223708B2
Application number: JP2009026881A
Authority: JP
Inventors: 隆史大賀; 信一神谷
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2009-02-09
Filing date: 2009-02-09
Publication date: 2013-06-26
Anticipated expiration: 2029-02-09
Also published as: JP2010181354A

Description

本発明は、吸気通路の内部に配設され、空気流量および空気温度を測定する空気流量測定装置に関する。 The present invention relates to an air flow rate measuring device that is disposed inside an intake passage and measures an air flow rate and an air temperature.

〔従来の技術〕
従来から、発熱抵抗体の放熱量を基に、空気流量を測定する熱式流量測定装置が公知であり、自動車用の内燃機関の吸入空気の流量を測定するエアフローメータとして採用されている（例えば、特許文献１参照）。 [Conventional technology]
2. Description of the Related Art Conventionally, a thermal flow measuring device that measures an air flow rate based on a heat release amount of a heating resistor is known, and is employed as an air flow meter that measures a flow rate of intake air of an internal combustion engine for an automobile (for example, , See Patent Document 1).

このエアフローメータ（空気流量測定装置）は、内燃機関の吸気管内に配置されたバイパス流路内に、流量測定素子である発熱抵抗体と感温抵抗体とが所定の間隔を有して設置されている。そして、この流量測定素子をドライブする制御回路内に抵抗ブリッジ回路等を構成することで発熱抵抗体の発熱温度と感温抵抗体の検出温度との温度差を一定に保つように発熱抵抗体の供給電流を制御して、その供給電流値に応じた電圧信号を出力する空気流量測定部を有している。そして、その電圧信号がＥＣＵに入力され、ＥＣＵによって吸入空気（吸気）の流量が算出されるものである。 In this air flow meter (air flow rate measuring device), a heating resistor and a temperature sensitive resistor, which are flow rate measuring elements, are installed at a predetermined interval in a bypass flow path disposed in an intake pipe of an internal combustion engine. ing. A resistance bridge circuit or the like is configured in the control circuit that drives the flow rate measuring element so that the temperature difference between the heating temperature of the heating resistor and the detected temperature of the temperature sensitive resistor is kept constant. An air flow rate measuring unit that controls the supply current and outputs a voltage signal corresponding to the supply current value is provided. Then, the voltage signal is input to the ECU, and the flow rate of intake air (intake) is calculated by the ECU.

また、バイパス流路を構成してなるセンサボディの外壁には、空気温度測定部が一体的に設けられ、温度測定素子（サーミスタ）によって、吸気管の流れ、つまり、吸気の温度を測定するようになっており、検出信号は直接ＥＣＵへ出力される。そして、この吸気の温度は内燃機関の吸気系システム全体を適正制御するための温度補償に利用される。 An air temperature measurement unit is integrally provided on the outer wall of the sensor body that forms the bypass flow path, and the flow of the intake pipe, that is, the temperature of the intake air is measured by the temperature measurement element (thermistor). The detection signal is directly output to the ECU. The intake air temperature is used for temperature compensation for appropriately controlling the entire intake system of the internal combustion engine.

ここで、従来から、吸気温度を測定する温度測定素子は、メイン流れの吸気からの伝熱以外の要因により測定温度が高温側にずれることが確認されている。即ち、空気流量測定装置は空気流量測定部と空気温度測定部とが近接されて配設されており、また、空気流量測定部をドライブする制御回路における発熱があり、この発熱する制御回路にも比較的近接して配設される温度測定素子に熱影響が生じて、吸気温度の測定結果に誤差を生じるものである。 Heretofore, it has been confirmed that the temperature measuring element for measuring the intake air temperature is shifted to the high temperature side due to factors other than heat transfer from the intake air of the main flow. In other words, the air flow measuring device is provided with the air flow measuring unit and the air temperature measuring unit in close proximity, and there is heat generation in the control circuit that drives the air flow measuring unit. A thermal effect is generated in the temperature measuring elements disposed relatively close to each other, and an error is caused in the measurement result of the intake air temperature.

図５は、代表的な内燃機関に搭載した空気流量測定装置の運転により、実際の空気温度と温度測定素子の検出温度との差異（つまり、誤差）を示したものである。そして、図５（ａ）は内燃機関が始動され制御回路が起動してからの時間経過に対して示したものであり、図５（ｂ）は吸気の空気流量の増加に対して示したものである。 FIG. 5 shows the difference (that is, error) between the actual air temperature and the detected temperature of the temperature measuring element due to the operation of the air flow rate measuring device mounted on a typical internal combustion engine. FIG. 5 (a) shows the passage of time after the internal combustion engine is started and the control circuit is started, and FIG. 5 (b) shows the increase of the intake air flow rate. It is.

図５（ａ）によれば、内燃機関の始動時、つまり制御回路の起動直後では、制御回路の発熱は未だ生じていないため、発熱による伝熱の影響はなく、検出温度との誤差はない。しかし、時間の経過とともに検出温度誤差が生じ、誤差は大きくなり、制御回路から単位時間当りに発生する熱は略一定なので、誤差もある大きさにて飽和する挙動となる。 According to FIG. 5 (a), when the internal combustion engine is started, that is, immediately after the control circuit is started, heat generation of the control circuit has not yet occurred. Therefore, there is no influence of heat transfer due to heat generation, and there is no error from the detected temperature. . However, a detected temperature error occurs with the passage of time, the error increases, and the heat generated per unit time from the control circuit is substantially constant, so that the error is saturated at a certain level.

また、図５（ｂ）によれば、流量の零時、つまり内燃機関を始動する前では、制御回路に発熱があれば、その熱影響を受けて検出温度との誤差が大きくなる。つまり、流量が零による冷却効果が作用しないためである。また、流量が僅かに生じるアイドリング時には、僅かではあるが空気が流れるので冷却効果が作用し、熱影響が抑えられて検出温度の誤差が小さくなる。そして、流量が増えれば、つまり通常運転域では、十分な冷却効果が作用し、熱影響が完全に防止されて検出温度の誤差はなくなる。 Further, according to FIG. 5B, when the flow rate is zero, that is, before the internal combustion engine is started, if the control circuit generates heat, an error from the detected temperature increases due to the heat effect. That is, the cooling effect due to the flow rate being zero does not work. Further, at the time of idling in which a flow rate is slightly generated, since air flows slightly, a cooling effect is exerted, a thermal effect is suppressed, and an error in detected temperature is reduced. If the flow rate is increased, that is, in the normal operation range, a sufficient cooling effect is exerted, the thermal effect is completely prevented, and the detected temperature error is eliminated.

従って、暖機状態となる通常運転を暫く持続させた後、内燃機関を停止して、そして、その後暫くして再始動して運転を開始するとき、この場合のアイドル域において、検出温度誤差が最も大きくなる恐れがある。 Therefore, when the normal operation that is in a warm-up state is continued for a while, the internal combustion engine is stopped, and then restarted for a while and then the operation is started. There is a risk of becoming the largest.

〔従来技術の不具合〕
従って、吸気の検出温度の誤差が無視できないほどに大きくなると、流量測定素子で検出した実際の流量値に対し演算され調整制御される種々の吸気系システムの特性値の吸気温度による温度補償にも誤差が生じて、吸気系システム上で適正制御にズレが生じるという問題がある。 [Problems with conventional technology]
Therefore, if the error in the detected temperature of the intake air becomes so large that it cannot be ignored, temperature compensation based on the intake air temperature of various intake system characteristics that are calculated and adjusted for the actual flow rate value detected by the flow rate measuring element There is a problem that an error occurs and the proper control is shifted on the intake system.

特開２００７−２７１５５７号公報JP 2007-271557 A

そこで、本発明は、上記問題に鑑みてなされたもので、空気温度測定素子の回路部における発熱による熱影響を極力低下させ、以って検出精度を向上した空気流量測定装置を提供することを目的とする。 Therefore, the present invention has been made in view of the above problems, and provides an air flow rate measuring device that can reduce the heat effect due to heat generation in the circuit portion of the air temperature measuring element as much as possible and thereby improve the detection accuracy. Objective.

〔請求項１の手段〕
請求項１に記載の手段によれば、空気流路を流れる空気の流線に対し略直交するように配置されるバイパス流路と、バイパス流路内に配設されて、空気流路を流れる空気流量を測定するセンシング部と、センシング部はバイパス流路内にバイパス流路の流れ方向に立設した１対の支持部材に接続支持される熱式流量測定素子を有しており、支持部材を通じて熱式流量測定素子に給電し供給電流を制御する回路部と、からなる空気流量測定部と、空気流路内に空気流量測定部と近接して配設されて、空気流路を流れる空気の温度を測定する空気温度測定素子を有しており、空気温度測定素子は空気流路内にバイパス流路の流れ方向に立設した１対の支持部材に、１対のリード部材を介して接続支持されるサーミスタからなり、支持部材を通じてサーミスタの検出信号を出力する空気温度測定部と、を一体的に備える空気流量測定装置において、空気温度測定素子の１対の支持部材を、空気流路を流れる空気の流線に対し、バイパス流路の流れ方向と直交する平面方向に傾斜して配置することを特徴としている。 [Means of Claim 1]
According to the first aspect of the present invention, the bypass channel disposed so as to be substantially orthogonal to the flow line of the air flowing through the air channel, and the bypass channel disposed in the bypass channel and flowing through the air channel. A sensing unit for measuring an air flow rate, and the sensing unit has a thermal flow rate measuring element connected to and supported by a pair of support members standing in the bypass channel in the flow direction of the bypass channel; An air flow rate measurement unit comprising: a circuit unit that supplies power to the thermal flow rate measurement element through and controls a supply current; and air that is disposed in the air flow path in proximity to the air flow rate measurement unit, and flows through the air flow path The air temperature measuring element measures the temperature of the air temperature measuring element, and the air temperature measuring element is provided in a pair of support members erected in the flow direction of the bypass flow path in the air flow path via a pair of lead members. It consists of a thermistor that is connected and supported, In the air flow rate measuring apparatus that integrally includes an air temperature measuring unit that outputs a detection signal of the mister, a pair of support members of the air temperature measuring element are bypassed with respect to an air stream line that flows through the air flow path. It is characterized by being inclined in a plane direction perpendicular to the flow direction of the road.

これにより、空気温度測定素子の１対の支持部材のそれぞれが、異なる空気の流線と衝突することができ、空気との熱伝達表面積が大きくなってそれぞれの支持部材の冷却を促進でき、制御回路部の発熱がサーミスタに伝達することを防止できる。 Thus, each of the pair of support members of the air temperature measuring element can collide with a different air stream line, and the heat transfer surface area with the air can be increased to promote the cooling of each support member. It is possible to prevent heat generated in the circuit unit from being transmitted to the thermistor.

〔請求項２の手段〕
請求項２に記載の手段によれば、空気温度測定素子のサーミスタと１対のリード部材を、空気流路を流れる空気の流線に対し、バイパス流路の流れ方向の平面方向に傾斜して配置することを特徴としている。
これにより、空気温度測定素子の１対のリード部材のそれぞれが、異なる空気の流線と衝突することができ、空気との熱伝達表面積が大きくなってそれぞれのリード部材の冷却を促進でき、制御回路部の発熱がサーミスタに伝達することを防止できる。 [Means of claim 2]
According to the means of claim 2, the thermistor of the air temperature measuring element and the pair of lead members are inclined in the plane direction of the flow direction of the bypass flow path with respect to the flow line of the air flowing through the air flow path. It is characterized by arranging.
Accordingly, each of the pair of lead members of the air temperature measuring element can collide with a different air stream line, and the heat transfer surface area with the air can be increased to promote the cooling of each lead member. It is possible to prevent heat generated in the circuit unit from being transmitted to the thermistor.

〔請求項３の手段〕
請求項３に記載の手段によれば、空気温度測定素子の１対の支持部材およびサーミスタと１対のリード部材とを、ともに空気流路を流れる空気の流線に対し、バイパス流路の流れ方向と直交する平面方向および流れ方向の平面方向の２方向に傾斜して配置することを特徴としている。
これにより、空気温度測定素子の１対の支持部材およびリード部材のそれぞれが、異なる空気の流線と衝突することができ、空気との熱伝達表面積が大きくなってそれぞれの支持部材およびリード部材の冷却を促進でき、制御回路部の発熱がサーミスタに伝達することを防止できる。 [Means of claim 3]
According to the third aspect of the present invention, the flow of the bypass flow path is configured such that the pair of support members and the thermistor of the air temperature measurement element and the pair of lead members are flowed along the air flow path. It is characterized by being inclined in two directions: a plane direction orthogonal to the direction and a plane direction of the flow direction.
As a result, each of the pair of support members and lead members of the air temperature measuring element can collide with different air streamlines, and the heat transfer surface area with the air becomes large, so that each of the support members and the lead members Cooling can be promoted, and heat generated by the control circuit unit can be prevented from being transmitted to the thermistor.

〔請求項４の手段〕
請求項４に記載の手段によれば、空気流路を流れる空気の流線を、空気温度測定素子の１対の支持部材および１対のリード部材が配設される長手方向に対し、傾斜して交差するように偏向したことを特徴としている。
これにより、空気温度測定素子の長手方向と空気の流線とは互いに相対角度を有して交差するので、異なる流線と接触または衝突することができ、同時に流れの境界層に乱れが生じ易く、よって熱伝達が大きくなって流れによる冷却効果が大きくなることによりサーミスタへの回路部からの伝熱が遮断され易くなる。 [Means of claim 4]
According to the means of the fourth aspect, the stream line of the air flowing through the air flow path is inclined with respect to the longitudinal direction in which the pair of support members and the pair of lead members of the air temperature measuring element are disposed. It is characterized by being deflected to intersect.
As a result, the longitudinal direction of the air temperature measuring element and the air stream line intersect with each other at a relative angle, so that they can contact or collide with different stream lines, and at the same time, the flow boundary layer is likely to be disturbed. Therefore, the heat transfer is increased and the cooling effect by the flow is increased, whereby the heat transfer from the circuit portion to the thermistor is easily interrupted.

空気流量測定装置の構成を示し、（ａ）は部分断面で示す正面図であり、（ｂ）は部分断面で示す側面図である（実施例１）。The structure of an air flow measuring device is shown, (a) is a front view shown with a partial cross section, (b) is a side view shown with a partial cross section (Example 1). 空気流量測定装置の要部である空気温度測定部の構成を示し、（ａ）は正面図であり、（ｂ）は側面図であり、（ｃ）は底面図である（実施例１）。The structure of the air temperature measurement part which is the principal part of an air flow measuring device is shown, (a) is a front view, (b) is a side view, (c) is a bottom view (Example 1). 空気流量測定装置の要部である空気温度測定部の構成を示し、（ａ）は正面図であり、（ｂ）は側面図であり、（ｃ）は底面図である（実施例２）。The structure of the air temperature measurement part which is the principal part of an air flow measuring device is shown, (a) is a front view, (b) is a side view, (c) is a bottom view (Example 2). 空気流量測定装置の要部である空気温度測定部の構成を示し、（ａ）は正面図であり、（ｂ）は側面図であり、（ｃ）は底面図である（実施例３）。The structure of the air temperature measurement part which is the principal part of an air flow measuring device is shown, (a) is a front view, (b) is a side view, (c) is a bottom view (Example 3). 空気温度測定部の検出温度誤差を示す特性図であり、（ａ）は内燃機関の始動後の経過時間に対し、（ｂ）は空気流量の増加に対して示したものである（従来例）。It is a characteristic view which shows the detection temperature error of an air temperature measurement part, (a) is shown with respect to the elapsed time after starting of an internal combustion engine, (b) is shown with respect to the increase in an air flow rate (conventional example). .

この発明の最良の実施形態を、図に示す実施例１とともに説明する。 The best mode of the present invention will be described together with Example 1 shown in the drawings.

〔実施例１の構成〕
図１、図２は、本発明の実施例１を示したもので、図１は空気流量測定装置の構成を示し、（ａ）は部分断面で示す正面図であり、（ｂ）は部分断面で示す側面図である。図２は、図１に示す空気流量測定装置の要部である空気温度測定部の構成を示し、（ａ）は正面図であり、（ｂ）は側面図であり、（ｃ）は底面図である。
本実施例に示す空気流量測定装置１は、例えば、自動車用の内燃機関（以下、エンジンと呼ぶ）の吸気の流量と温度を計測するものであり、図１に示すように、図示しないエアクリーナと接続する空気通路を形成する吸気管２にプラグイン方式によって、着脱可能に取付けられている。 [Configuration of Example 1]
1 and 2 show Embodiment 1 of the present invention. FIG. 1 shows the configuration of an air flow rate measuring device, (a) is a front view showing a partial cross section, and (b) is a partial cross section. It is a side view shown by. 2 shows a configuration of an air temperature measuring unit that is a main part of the air flow measuring device shown in FIG. 1, wherein (a) is a front view, (b) is a side view, and (c) is a bottom view. It is.
The air flow rate measuring apparatus 1 shown in the present embodiment measures, for example, the flow rate and temperature of intake air of an automobile internal combustion engine (hereinafter referred to as an engine). As shown in FIG. It is detachably attached to the intake pipe 2 forming an air passage to be connected by a plug-in method.

この空気流量測定装置１は、空気流量測定部３０と空気温度測定部４０とからなっている。空気流量測定部３０は、センサボディ３、センシング部４、および回路部５等から構成される。センサボディ３は、メイン流路６を形成する吸気管２の管壁に開けられた取付け孔より吸気管２の内部に挿入され、吸気管２の中心軸に対して、略直交するように配置される。センサボディ３の内部には、吸気管２のメイン流路６内を流れる空気流れの一部をバイパスさせるバイパス流れ（図中点線矢印参照）を形成するバイパス流路７が形成される。従って、バイパス流路７は、センサボディ３に形成される入口８に対して、メイン流れから略９０度偏向された空気流れが流入し、また、センサボディ３に形成される出口９に対して、空気の流れ方向が１８０度変化（Ｕターン）して流出するように形成されている。 The air flow rate measuring device 1 includes an air flow rate measuring unit 30 and an air temperature measuring unit 40. The air flow rate measurement unit 30 includes a sensor body 3, a sensing unit 4, a circuit unit 5, and the like. The sensor body 3 is inserted into the intake pipe 2 through a mounting hole formed in the pipe wall of the intake pipe 2 that forms the main flow path 6, and is arranged so as to be substantially orthogonal to the central axis of the intake pipe 2. Is done. Inside the sensor body 3, a bypass flow path 7 is formed that forms a bypass flow (see a dotted arrow in the figure) that bypasses a part of the air flow flowing in the main flow path 6 of the intake pipe 2. Accordingly, the bypass flow path 7 receives an air flow deflected by approximately 90 degrees from the main flow with respect to the inlet 8 formed in the sensor body 3, and is connected to the outlet 9 formed in the sensor body 3. The air flow direction changes by 180 degrees (U-turn) and flows out.

センシング部４は、バイパス流路７を流れる空気流量を測定するための発熱抵抗体１０と、バイパス流路７の空気温度を測定するための感温抵抗体１１とを有し、各抵抗体１０、１１が１対の支持部材１３の先端部間を端渡すようにリード部材１２によって位置決めされ、図１（ｂ）に示すように、バイパス流路７のＵターン部より上流側で、略９０度偏向流れとなる入口８より下流側に配置される。 The sensing unit 4 includes a heating resistor 10 for measuring the air flow rate through the bypass flow path 7 and a temperature sensitive resistor 11 for measuring the air temperature of the bypass flow path 7. , 11 are positioned by the lead member 12 so as to pass between the front ends of the pair of support members 13, and as shown in FIG. It is arrange | positioned downstream from the inlet 8 used as a deflection flow.

発熱抵抗体１０は、例えば、外径０．０２ｍｍの白金線をボビンの外周面に巻き付けて形成され、その白金線の両端部が、ボビンの両端に取り付けられる１対のリード部材１２に接続されて、発熱抵抗体１０およびリード部材１２の表面が保護膜によって被覆されている。一方、感温抵抗体１１は、発熱抵抗体１０と同様に、ボビンの外周面に白金線を巻き付けて形成され、その白金線の両端部がボビンの両端に取り付けられる１対のリード部材１２に接続されて、感温抵抗体１１およびリード部材１２の表面が保護膜によって被覆されている。 The heating resistor 10 is formed, for example, by winding a platinum wire having an outer diameter of 0.02 mm around the outer peripheral surface of the bobbin, and both ends of the platinum wire are connected to a pair of lead members 12 attached to both ends of the bobbin. The surfaces of the heating resistor 10 and the lead member 12 are covered with a protective film. On the other hand, the temperature sensitive resistor 11 is formed by winding a platinum wire around the outer peripheral surface of the bobbin, like the heat generating resistor 10, and a pair of lead members 12 to which both ends of the platinum wire are attached to both ends of the bobbin. Connected, the surfaces of the temperature sensitive resistor 11 and the lead member 12 are covered with a protective film.

支持部材１３は、センサボディ３の他端側に配置される回路部５の構造壁に、バイパス流路７内のバイパス流れ方向に立設され、バイパス流れの流線方向とその長手方向とを一致させてある。そして、回路部５に内蔵される回路基板（図示せず）とリード部材１２とを電気的に接続するターミナルを兼ねており、その断面形状が矩形または円形の導電材により構成されている。 The support member 13 is erected on the structural wall of the circuit unit 5 disposed on the other end side of the sensor body 3 in the bypass flow direction in the bypass flow path 7, and the streamline direction of the bypass flow and the longitudinal direction thereof are defined. It is matched. The circuit board 5 also serves as a terminal for electrically connecting a circuit board (not shown) built in the circuit unit 5 and the lead member 12, and the cross-sectional shape thereof is made of a rectangular or circular conductive material.

上記の発熱抵抗体１０と感温抵抗体１１は、図１（ａ）、（ｂ）に示すように、各抵抗体１０、１１の長手方向がメイン流れ方向（図１（ｂ）左右（Ｘ軸）方向）となるように配置され、バイパス流れ方向（図１（ｂ）上下（Ｚ軸）方向）に所定の距離と、バイパス流れと直角方向（図１（ａ）左右（Ｙ軸）方向）に、同様に所定の距離だけ離れて配置される。また、感温抵抗体１１が発熱抵抗体１０より上流側に配置され、各リード部材１２が接続される支持部材１３を介して、回路部５に内蔵される回路基板に電気的に接続されている。なお、本実施例では、感温抵抗体１１が発熱抵抗体１０より上流側に配置したが、これに限ることなく、発熱抵抗体１０が感温抵抗体１１より上流側に配置されていてもよい。 As shown in FIGS. 1A and 1B, the heating resistor 10 and the temperature sensitive resistor 11 have the longitudinal direction of each resistor 10, 11 in the main flow direction (FIG. 1B left and right (X (Axis) direction), a predetermined distance in the bypass flow direction (FIG. 1 (b) up and down (Z axis) direction), and a direction perpendicular to the bypass flow (FIG. 1 (a) left and right (Y axis) direction ) Are similarly spaced apart by a predetermined distance. Further, the temperature-sensitive resistor 11 is disposed on the upstream side of the heating resistor 10 and is electrically connected to a circuit board built in the circuit unit 5 via a support member 13 to which each lead member 12 is connected. Yes. In the present embodiment, the temperature sensitive resistor 11 is arranged on the upstream side of the heating resistor 10. However, the present invention is not limited to this, and the heating resistor 10 may be arranged on the upstream side of the temperature sensitive resistor 11. Good.

回路部５は、センサボディ３の他端側に設けられ、吸気管２の取付け孔より外側に配置される。この回路部５は、発熱抵抗体１０の温度と感温抵抗体１１で検出される空気温度との差が常に一定となるように、例えば、抵抗ブリッジ回路を構成することにより、発熱抵抗体１０に供給される電流値を制御している。そして、この発熱抵抗体１０に供給される電流値に応じた電圧信号が、回路部５からコネクタ１４を介して図示しないＥＣＵへ出力され、そのＥＣＵにより予め作成した（電圧−流量）マップから吸入空気量が算出（計算）される。なお、ＥＣＵはエンジンの吸気系システム全体、例えば、空燃比制御や点火進角制御などを適正制御する電子制御装置である。 The circuit unit 5 is provided on the other end side of the sensor body 3 and is disposed outside the attachment hole of the intake pipe 2. For example, the circuit unit 5 includes a resistance bridge circuit so that the difference between the temperature of the heating resistor 10 and the air temperature detected by the temperature-sensitive resistor 11 is always constant, thereby forming the heating resistor 10. The current value supplied to is controlled. A voltage signal corresponding to the current value supplied to the heating resistor 10 is output from the circuit unit 5 to the ECU (not shown) via the connector 14 and is sucked from a (voltage-flow rate) map created in advance by the ECU. The amount of air is calculated (calculated). The ECU is an electronic control device that appropriately controls the entire intake system of the engine, for example, air-fuel ratio control and ignition advance control.

一方、空気温度測定部４０は、センサボディ３の中央部外壁に設けられてメイン流れを整流するとともに保護板としてのガイドカバー１５と、ガイドカバー１５に囲まれた中に空気温度測定素子２０が配設されている。空気温度測定素子２０はサーミスタ１６が１対の支持部材１８の先端部間を端渡すようにリード部材１７によって空間位置に固定されて構成される。 On the other hand, the air temperature measurement unit 40 is provided on the outer wall of the central portion of the sensor body 3 to rectify the main flow, and the guide cover 15 as a protection plate, and the air temperature measurement element 20 is surrounded by the guide cover 15. It is arranged. The air temperature measuring element 20 is configured such that the thermistor 16 is fixed at a spatial position by the lead member 17 so as to pass between the tip portions of the pair of support members 18.

サーミスタ１６は、大きな負の電気抵抗温度係数を有した半導体からなり、円柱状のチップに導電材よりなる１対のリード部材１７をその端部に接合した一般的な温度センサの構造を有している。サーミスタ１６は検出感度が高く、動作温度をあまり高くしなくて済む常温近傍の高精度の温度測定には好適なものである。 The thermistor 16 is made of a semiconductor having a large negative electric resistance temperature coefficient, and has a general temperature sensor structure in which a pair of lead members 17 made of a conductive material are joined to the end of a cylindrical chip. ing. The thermistor 16 has high detection sensitivity, and is suitable for high-accuracy temperature measurement in the vicinity of room temperature where the operating temperature does not need to be so high.

また、支持部材１８はその断面が矩形状の導電材により構成され、センサボディ３の他端側に配置される回路部５の構造壁から突出するホルダ１９内にインサート成形され、一端側はサーミスタ１６を電気的に接続し、他端側はコネクタ１４のターミナルと直接に接続する構造となっている。そして、回路部５の構造壁にＺ軸方向に立設されるセンシング部４の支持部材１３と平行に配置されている。 The support member 18 is formed of a conductive material having a rectangular cross section, and is insert-molded into a holder 19 protruding from the structural wall of the circuit unit 5 disposed on the other end side of the sensor body 3, and one end side is the thermistor. 16 is electrically connected, and the other end is directly connected to the terminal of the connector 14. And it is arrange | positioned in parallel with the support member 13 of the sensing part 4 standingly arranged by the Z-axis direction on the structural wall of the circuit part 5. FIG.

ここで、本実施例では、本発明の空気温度測定部４０は、メイン流路６内のメイン流れの流線（Ｘ軸）方向に対して空気温度測定素子２０の配設を傾斜させたことを特徴としている。以下に、図２に基づいて詳細に説明する。 Here, in the present embodiment, the air temperature measurement unit 40 of the present invention inclines the arrangement of the air temperature measurement element 20 with respect to the streamline (X axis) direction of the main flow in the main flow path 6. It is characterized by. Below, it demonstrates in detail based on FIG.

本発明の支持部材１８は、図２（ｃ）に示すように、それぞれの断面形状は矩形状であるが、矩形状の長辺のそれぞれに接する仮想的接線が、メイン流れの流線（Ｘ軸）方向に対して傾斜角θだけＹ軸側に傾くようにホルダ１９にインサート成形される。 As shown in FIG. 2C, the support member 18 of the present invention has a rectangular cross section, but the virtual tangent line in contact with each of the long sides of the rectangular shape is the main stream streamline (X The holder 19 is insert-molded so as to be inclined toward the Y-axis side by an inclination angle θ with respect to the (axis) direction.

そして、両端にリード部材１７が接続されたサーミスタ１６が、Ｘ軸方向に対して傾斜角θを形成して配設された支持部材１８の一端側の所定の位置に、支持部材１８の先端部間を端渡すように配置され接合される。このとき、リード部材１７が接続されたサーミスタ１６の長手方向は、図２（ｂ）に示すように、Ｘ軸方向（図示水平方向）に一致するように配置され、Ｚ軸側への傾斜は全く生じないように、つまり水平に配設される。そして、支持部材１８の他端側は、直接コネクタ１４のターミナルと接続されて、電気的な導通を得ている。 Then, the thermistor 16 having the lead members 17 connected to both ends is arranged at a predetermined position on one end side of the support member 18 provided with an inclination angle θ with respect to the X-axis direction. It is arranged and joined so as to pass the gap. At this time, as shown in FIG. 2B, the thermistor 16 to which the lead member 17 is connected is arranged so as to coincide with the X-axis direction (the horizontal direction in the drawing), and the inclination to the Z-axis side is It is arranged horizontally so that it does not occur at all. The other end side of the support member 18 is directly connected to the terminal of the connector 14 to obtain electrical continuity.

これにより、メイン流れの流線に対し１対の支持部材１８のそれぞれは互いにズレた配置を有することより、常に異なる流線と接触することとなり、少なくとも１対の支持部材１８が同じ流線上に重なる場合よりも、流れとの接触または衝突が促進され、支持部材１８と流線との熱伝達が大きくなって、流れによる支持部材１８の冷却効果が促進することとなる。よって、支持部材１８に回路部５の発熱による熱伝導が生じても、流れによる冷却効果が大きくなることによりサーミスタ１６への伝熱が遮断され、サーミスタ１６は周囲の空気温度のみに呼応した真の空気温度を計測できる。 As a result, each of the pair of support members 18 is displaced from each other with respect to the main flow streamline, so that it always comes into contact with different streamlines, so that at least one pair of support members 18 are on the same streamline. Compared with the case where they overlap, the contact or collision with the flow is promoted, the heat transfer between the support member 18 and the stream line is increased, and the cooling effect of the support member 18 by the flow is promoted. Therefore, even if heat conduction due to the heat generation of the circuit unit 5 occurs in the support member 18, the heat transfer effect to the thermistor 16 is cut off by increasing the cooling effect due to the flow, and the thermistor 16 is a true detector that responds only to the ambient air temperature. The air temperature can be measured.

また、空気温度測定素子２０も流れの流線と傾くことにより、リード部材１７およびサーミスタ１６自体の流れに対する傾きによって、リード部材１７およびサーミスタ１６自体の流れに対する傾きがないときよりも、それぞれの表面に生じる流れの境界層に乱れが生じ易く、よって熱伝達が大きくなって、同様に、流れによる冷却効果が大きくなることによりサーミスタ１６への回路部５からの伝熱が遮断されやすくなる。 Further, the air temperature measuring element 20 is also inclined with respect to the flow line of the flow, so that the inclination of the lead member 17 and the thermistor 16 itself with respect to the flow causes the surface of each of them to be smaller than when there is no inclination with respect to the flow of the lead member 17 and thermistor 16 itself. The flow boundary layer is easily disturbed, and thus heat transfer is increased. Similarly, the cooling effect by the flow is increased, so that heat transfer from the circuit unit 5 to the thermistor 16 is easily interrupted.

〔実施例１の作用〕
エンジンの始動により、吸気管２の内部に空気の流れ（メイン流れ）が発生すると、メイン流れの一部がセンサボディ３のバイパス流路７にメイン流れから略９０度偏向されたバイパス流れとなって流入する。このバイパス流れによって発熱抵抗体１０は表面からの放熱を受け、放熱によって温度が低下すると発熱抵抗体１０の抵抗値が変化する。すると、感温抵抗体１１で測定される空気温度との温度差を一定に保つために、発熱抵抗体１０に供給される電流値が増加し、発熱も増加する。このとき、この電流値が空気流量測定部３０を流れた空気流量に比例するので、この電流値に応じた電圧信号がＥＣＵへ出力される。 [Operation of Example 1]
When an air flow (main flow) is generated inside the intake pipe 2 due to the start of the engine, a part of the main flow becomes a bypass flow deflected approximately 90 degrees from the main flow into the bypass flow path 7 of the sensor body 3. Inflow. The heat generating resistor 10 receives heat from the surface by this bypass flow, and the resistance value of the heat generating resistor 10 changes when the temperature decreases due to heat dissipation. Then, in order to keep the temperature difference with the air temperature measured by the temperature sensitive resistor 11 constant, the current value supplied to the heating resistor 10 increases and the heat generation also increases. At this time, since this current value is proportional to the air flow rate flowing through the air flow rate measurement unit 30, a voltage signal corresponding to this current value is output to the ECU.

また、メイン流れが発生することでメイン流路６内に配置された空気温度測定部４０のサーミスタ１６によってメイン流れの空気温度が測定され検出信号がＥＣＵへ出力される。そして、それぞれの検出信号を入力されたＥＣＵは、内蔵する（電圧−流量）マップに従って所定のサンプリングタイム毎に流量を瞬時に演算するとともに、計測された吸気温度に基づく補償演算を経てエンジンの吸気系システムの最適化制御を実行する。 In addition, when the main flow is generated, the thermistor 16 of the air temperature measuring unit 40 disposed in the main flow path 6 measures the air temperature of the main flow and outputs a detection signal to the ECU. The ECUs to which the respective detection signals are input calculate the flow rate instantaneously at a predetermined sampling time according to a built-in (voltage-flow rate) map, and after performing the compensation calculation based on the measured intake air temperature, Performs optimization control of the system.

そして、さらにエンジン回転数が上がり、メイン流れが多くなりバイパス流れも多くなると、発熱抵抗体１０の放熱量が増大するため、感温抵抗体１１で測定される空気温度との温度差を一定に保つために、発熱抵抗体１０に通電される電流値が大きくなる。逆に、エンジン回転数が下がり、バイパス流れが少なくなると、発熱抵抗体１０の放熱量が低減するため、発熱抵抗体１０に通電される電流値も小さくなる。そして、イグニッションスイッチを切ってエンジンを停止すると、流量はなくなり検出信号は零となる。 When the engine speed further increases, the main flow increases and the bypass flow increases, the heat dissipation amount of the heating resistor 10 increases, so the temperature difference from the air temperature measured by the temperature sensitive resistor 11 is kept constant. In order to keep it, the value of the current supplied to the heating resistor 10 increases. On the contrary, when the engine speed is reduced and the bypass flow is reduced, the heat radiation amount of the heating resistor 10 is reduced, so that the current value supplied to the heating resistor 10 is also reduced. Then, when the ignition switch is turned off and the engine is stopped, the flow rate is lost and the detection signal becomes zero.

〔実施例１の効果〕
本実施例では、メイン流路６を流れる空気の流線に対し略直交するように配置されるバイパス流路７内に配設されて、メイン流路６を流れる空気流量を測定するセンシング部４と、センシング部４はバイパス流路７内にバイパス流路７の流れ方向に立設した１対の支持部材１３に接続支持される熱式流量測定素子を有しており、支持部材１３を通じて熱式流量測定素子に給電し供給電流を制御する回路部５と、からなる空気流量測定部３０と、メイン流路６内に配設されて、メイン流路６を流れる空気の温度を測定する空気温度測定素子２０を有しており、空気温度測定素子２０はメイン流路６内にバイパス流路７の流れ方向に立設した１対の支持部材１８に、１対のリード部材１７を介して接続支持されるサーミスタ１６からなる空気温度測定部４０と、を一体的に備える空気流量測定装置１において、空気温度測定素子２０の１対の支持部材１８を、メイン流路６を流れる空気の流線に対し、バイパス流路７の流れ方向と直交する平面方向に傾斜して配置した。 [Effect of Example 1]
In the present embodiment, the sensing unit 4 that is disposed in a bypass flow path 7 that is disposed so as to be substantially orthogonal to a flow line of air flowing through the main flow path 6, and measures the flow rate of air flowing through the main flow path 6. The sensing unit 4 has a thermal flow rate measuring element connected to and supported by a pair of support members 13 erected in the flow direction of the bypass flow channel 7 in the bypass flow channel 7. An air flow rate measurement unit 30 comprising a circuit unit 5 for supplying power to the flow rate measuring element and controlling a supply current, and an air that is disposed in the main flow channel 6 and measures the temperature of the air flowing through the main flow channel 6 The air temperature measuring element 20 has a pair of support members 18 erected in the flow direction of the bypass flow path 7 in the main flow path 6 via a pair of lead members 17. Air temperature consisting of thermistor 16 connected and supported In the air flow rate measuring apparatus 1 that is integrally provided with the fixed portion 40, the pair of support members 18 of the air temperature measuring element 20 is flowed through the bypass flow path 7 with respect to the air flow line flowing through the main flow path 6. Inclined in the plane direction orthogonal to the direction.

これにより、空気温度測定素子２０の１対の支持部材１８のそれぞれが、異なる空気の流線と接触または衝突することができ、空気との熱伝達表面積が大きくなってそれぞれの支持部材１８の冷却効果を促進でき、回路部５の発熱がサーミスタ１６に伝達することを防止できる。 As a result, each of the pair of support members 18 of the air temperature measuring element 20 can contact or collide with a different air stream line, and the heat transfer surface area with the air is increased, thereby cooling each support member 18. An effect can be accelerated | stimulated and it can prevent that the heat_generation | fever of the circuit part 5 is transmitted to the thermistor 16. FIG.

〔実施例２の構成〕
本発明の実施例２を図３に示す。図３は、空気流量測定装置の要部である空気温度測定部の構成を示し、（ａ）は正面図であり、（ｂ）は側面図であり、（ｃ）は底面図である。実施例１と実質的に同一構成部分に同一符号を付して、詳細な説明は省略する。 [Configuration of Example 2]
A second embodiment of the present invention is shown in FIG. FIG. 3 shows a configuration of an air temperature measuring unit which is a main part of the air flow rate measuring device, where (a) is a front view, (b) is a side view, and (c) is a bottom view. Components that are substantially the same as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

実施例１では、空気流量測定装置１の要部である空気温度測定部４０は、空気温度測定素子２０を構成する断面が矩形状の１対の支持部材１８の配設を、矩形状の長辺のそれぞれに接する仮想的接線が、メイン流れの流線（Ｘ軸）方向に対して傾斜角θだけＹ軸側に傾くようにホルダ１９にインサートする構成を採用している。 In the first embodiment, the air temperature measuring unit 40 that is a main part of the air flow rate measuring device 1 is configured by arranging a pair of support members 18 having a rectangular cross section constituting the air temperature measuring element 20 in a rectangular shape. A configuration is adopted in which the virtual tangent tangent to each of the sides is inserted into the holder 19 so as to be inclined toward the Y axis side by an inclination angle θ with respect to the streamline (X axis) direction of the main flow.

本実施例では、１対の支持部材１８の配設を流線（Ｘ軸）方向に対して傾けるのでなく、１対の支持部材１８の配設は流線（Ｘ軸）方向に沿って流線上に並ぶようにホルダ１９にインサートする構成であり、空気温度測定素子２０のリード部材１７が接続されたサーミスタ１６が、流線方向（Ｘ軸方向）に対して傾斜角φを形成してＺ軸方向に傾けて固定される構成を採用している。 In the present embodiment, the arrangement of the pair of support members 18 is not inclined with respect to the streamline (X axis) direction, but the arrangement of the pair of support members 18 flows along the streamline (X axis) direction. The thermistor 16 to which the lead member 17 of the air temperature measuring element 20 is connected is formed with an inclination angle φ with respect to the streamline direction (X-axis direction). A configuration that is tilted and fixed in the axial direction is adopted.

これにより、リード部材１７およびサーミスタ１６自体が異なる流線と接触または衝突することとなり、リード部材１７およびサーミスタ１６自体の流れに対する傾きがないときよりも、それぞれの表面に生じる流れの境界層に乱れが生じ易くなり熱伝達が大きくなって、流れによる冷却効果が促進する。よって、サーミスタ１６への回路部からの伝熱が遮断されやすくなる。 As a result, the lead member 17 and the thermistor 16 themselves come into contact with or collide with different streamlines, and the boundary layers of the flow generated on the respective surfaces are more disturbed than when the lead member 17 and the thermistor 16 themselves are not inclined with respect to the flow. Is likely to occur, heat transfer is increased, and the cooling effect by the flow is promoted. Therefore, heat transfer from the circuit unit to the thermistor 16 is easily blocked.

〔実施例３の構成〕
本発明の実施例３を図４に示す。図４は、空気流量測定装置の要部である空気温度測定部の構成を示し、（ａ）は正面図であり、（ｂ）は側面図であり、（ｃ）は底面図である。実施例１と実質的に同一構成部分に同一符号を付して、詳細な説明は省略する。 [Configuration of Example 3]
A third embodiment of the present invention is shown in FIG. FIG. 4 shows a configuration of an air temperature measuring unit that is a main part of the air flow rate measuring device, where (a) is a front view, (b) is a side view, and (c) is a bottom view. Components that are substantially the same as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

本実施例では、空気温度測定素子２０の配設を、実施例１で採用した１対の支持部材１８の配設を矩形状の長辺のそれぞれに接する仮想的接線が、メイン流れの流線（Ｘ軸）方向に対して傾斜角θだけＹ軸側に傾くようにホルダ１９にインサートする構成に、実施例２で採用したリード部材１７が接続されたサーミスタ１６が、流線方向（Ｘ軸方向）に対して傾斜角φを形成してＺ軸方向に傾けて固定される構成を組合わせて採用している。 In the present embodiment, the arrangement of the air temperature measuring element 20 and the virtual tangent line in contact with each of the long sides of the rectangular shape of the pair of support members 18 employed in the first embodiment are streamlines of the main flow. The thermistor 16 to which the lead member 17 employed in the second embodiment is connected is inserted in the holder 19 so as to be inclined to the Y axis side by an inclination angle θ with respect to the (X axis) direction. A configuration in which an inclination angle φ is formed with respect to (direction) and is tilted and fixed in the Z-axis direction is used in combination.

従って、リード部材１７が接続されたサーミスタ１６は流れの流線（Ｘ軸）方向に対しＹ軸方向に傾斜角θとＺ軸方向に傾斜角φの２方向の傾きを有して配設されることとなり、これにより、２方向側の流れの流線と接触または衝突することが可能となり、さらに、境界層に乱れが生じ易くなり熱伝達が大きくなって、流れによる冷却効果が促進する。よって、サーミスタ１６への回路部からの伝熱が遮断されやすくなる。 Therefore, the thermistor 16 to which the lead member 17 is connected is disposed with an inclination in two directions, an inclination angle θ in the Y-axis direction and an inclination angle φ in the Z-axis direction with respect to the flow line (X-axis) direction of the flow. As a result, it becomes possible to contact or collide with the streamlines of the flow in the two directions, and further, the boundary layer is likely to be disturbed, heat transfer is increased, and the cooling effect by the flow is promoted. Therefore, heat transfer from the circuit unit to the thermistor 16 is easily blocked.

〔変形例１〕
上述した実施例１〜３では、空気温度測定素子２０のサーミスタ１６への空気流量測定部３０の回路部５からの発熱による伝熱を遮断するために、流れの流線（Ｘ軸）方向に対し空気温度測定素子２０を傾けて配設することで異なる流線と接触または衝突しやすくして、流れの境界層に乱れを生じ易くして熱伝達を大きくし、流れによる冷却効果を促進している。 [Modification 1]
In the above-described first to third embodiments, in order to block heat transfer due to heat generation from the circuit unit 5 of the air flow rate measuring unit 30 to the thermistor 16 of the air temperature measuring element 20, in the flow streamline (X axis) direction. On the other hand, the air temperature measuring element 20 is disposed at an angle so that it can easily contact or collide with different streamlines, easily disturb the flow boundary layer, increase heat transfer, and promote the cooling effect by the flow. ing.

しかし、流れの流線（Ｘ軸）方向に対し空気温度測定素子２０を傾けて配設することに限ることなく、空気温度測定素子２０は流れの流線（Ｘ軸）方向に配設したままで、流れの流線をＸ軸方向に対し所定の傾斜角だけ傾けてもよい。 However, the air temperature measuring element 20 is not limited to being inclined and disposed with respect to the flow streamline (X axis) direction, and the air temperature measuring element 20 remains disposed in the flow streamline (X axis) direction. Thus, the streamline of the flow may be inclined by a predetermined inclination angle with respect to the X-axis direction.

流れの流線を所定の傾斜角だけ傾けるには、例えば、空気温度測定素子２０を内部に収容し、流れの整流と保護板となるガイドカバー１５の内側に、流れの流線を偏向させる偏向板を設けたり、あるいはガイドカバー１５自体を流れの流線に対して傾斜して配設し、流線を所定の角度だけ偏向させてもよい。 In order to incline the flow stream line by a predetermined inclination angle, for example, the air temperature measuring element 20 is housed inside, and the flow stream is deflected and deflected to deflect the flow stream line inside the guide cover 15 serving as a protective plate. A plate may be provided, or the guide cover 15 itself may be disposed to be inclined with respect to the streamline of the flow, and the streamline may be deflected by a predetermined angle.

これにより、空気温度測定素子２０を傾けて配設した場合と同様な作用効果が得られるが、本変形例では、さらに、流れの流線を傾けるので、例えば、流れに混流するダストやミスト等の比較的大きくて重い浮遊粒子は慣性作用によって捕獲することが可能となる。従って、空気温度測定素子２０への浮遊粒子の付着の抑制を実現できるという特別な効果もある。 Thereby, the same effect as that obtained when the air temperature measuring element 20 is tilted can be obtained. However, in this modified example, the streamline of the flow is further tilted, so that, for example, dust or mist mixed in the flow, etc. The relatively large and heavy suspended particles can be captured by inertial action. Therefore, there is a special effect that it is possible to suppress the adhesion of suspended particles to the air temperature measuring element 20.

〔変形例２〕
変形例１では、空気温度測定素子２０に傾いた流線と接触させることで流れによる冷却効果を促進してサーミスタ１６への伝熱を遮断するものであるが、これに限ることなく、空気温度測定素子２０への伝熱量自体を低下させる構成であってもよい。 [Modification 2]
In the first modification, the air temperature measuring element 20 is brought into contact with an inclined streamline to promote the cooling effect by the flow and cut off the heat transfer to the thermistor 16, but the air temperature is not limited to this. The structure which reduces the heat-transfer amount itself to the measurement element 20 may be sufficient.

伝熱量自体を低下させるには、空気温度測定素子２０を構成する、例えば、１対の支持部材１８の構成材質を、導電材であるが、熱伝導度の小さい素材としたり、また、１対のリード部材１７においては、その線径を細くするとともにリード長さを長くしたりすることで対応が可能となる。 In order to reduce the heat transfer amount itself, for example, the constituent material of the pair of support members 18 constituting the air temperature measuring element 20 is a conductive material, but a material having a low thermal conductivity may be used. This lead member 17 can be dealt with by reducing the wire diameter and increasing the lead length.

これにより、空気温度測定素子２０と流線との間に相対角度を設けた場合と同様な作用効果が得られるが、本変形例では、さらに、熱伝導度が小さい分、空気温度測定素子２０をコンパクトに収めることが可能となる。 As a result, the same effect as that obtained when a relative angle is provided between the air temperature measuring element 20 and the streamline can be obtained. However, in the present modification, the air temperature measuring element 20 is further reduced due to the lower thermal conductivity. Can be housed compactly.

１空気流量測定装置
４センシング部
５回路部
６メイン流路（空気流路）
７バイパス流路
１０発熱抵抗体（熱式流量測定素子）
１１感温抵抗体（熱式流量測定素子）
１２、１７リード部材
１３、１８支持部材
１６サーミスタ
２０空気温度測定素子
３０空気流量測定部
４０空気温度測定部 DESCRIPTION OF SYMBOLS 1 Air flow measuring device 4 Sensing part 5 Circuit part 6 Main flow path (air flow path)
7 Bypass channel 10 Heating resistor (thermal flow measuring element)
11 Temperature sensitive resistor (thermal flow measuring element)
12, 17 Lead members 13 and 18 Support member 16 Thermistor 20 Air temperature measuring element 30 Air flow rate measuring unit 40 Air temperature measuring unit

Claims

A bypass channel disposed so as to be substantially orthogonal to a streamline of air flowing through the air channel;
A sensing unit that is disposed in the bypass channel and measures an air flow rate flowing through the air channel;
The sensing unit has a thermal flow measuring element connected to and supported by a pair of support members erected in the bypass channel in the flow direction of the bypass channel,
A circuit unit for supplying power to the thermal flow rate measuring element through the support member and controlling a supply current;
An air flow rate measuring unit comprising:
An air temperature measuring element that is disposed in the air flow path in proximity to the air flow rate measurement unit and measures the temperature of the air flowing through the air flow path;
The air temperature measuring element is composed of a thermistor connected and supported via a pair of lead members to a pair of support members standing in the air flow path in the flow direction of the bypass flow path.
An air temperature measurement unit that outputs a detection signal of the thermistor through the support member;
In an air flow rate measuring device integrally comprising:
The pair of support members of the air temperature measuring element are arranged so as to be inclined with respect to the streamline of air flowing through the air flow path in a plane direction perpendicular to the flow direction of the bypass flow path. Air flow measuring device.

A bypass channel disposed so as to be substantially orthogonal to a streamline of air flowing through the air channel;
A sensing unit that is disposed in the bypass channel and measures an air flow rate flowing through the air channel;
The sensing unit has a thermal flow measuring element connected to and supported by a pair of support members erected in the bypass channel in the flow direction of the bypass channel,
A circuit unit for supplying power to the thermal flow rate measuring element through the support member and controlling a supply current;
An air flow rate measuring unit comprising:
An air temperature measuring element that is disposed in the air flow path in proximity to the air flow rate measurement unit and measures the temperature of the air flowing through the air flow path;
The air temperature measuring element is composed of a thermistor connected and supported via a pair of lead members to a pair of support members standing in the air flow path in the flow direction of the bypass flow path.
An air temperature measurement unit that outputs a detection signal of the thermistor through the support member;
In an air flow rate measuring device integrally comprising :
The thermistor and the pair of lead members of the air temperature measuring element are arranged so as to be inclined in a plane direction of the flow direction of the bypass flow path with respect to a flow line of air flowing through the air flow path. Air flow measuring device.

The air flow rate measuring device according to claim 1 ,
The thermistor and the pair of lead members of the air temperature measuring element are arranged so as to be inclined in a plane direction of the flow direction of the bypass flow path with respect to a flow line of air flowing through the air flow path. Air flow measuring device.

A bypass channel disposed so as to be substantially orthogonal to a streamline of air flowing through the air channel;
A sensing unit that is disposed in the bypass channel and measures an air flow rate flowing through the air channel;
The sensing unit has a thermal flow measuring element connected to and supported by a pair of support members erected in the bypass channel in the flow direction of the bypass channel,
A circuit unit for supplying power to the thermal flow rate measuring element through the support member and controlling a supply current;
An air flow rate measuring unit comprising:
An air temperature measuring element that is disposed in the air flow path in proximity to the air flow rate measurement unit and measures the temperature of the air flowing through the air flow path;
The air temperature measuring element is composed of a thermistor connected and supported via a pair of lead members to a pair of support members standing in the air flow path in the flow direction of the bypass flow path.
An air temperature measurement unit that outputs a detection signal of the thermistor through the support member;
In an air flow rate measuring device integrally comprising :
The flow line of the air flowing through the air flow path is deflected so as to intersect with the longitudinal direction in which the pair of support members and the pair of lead members of the air temperature measuring element are disposed. An air flow rate measuring device characterized by that .