JP2000162011A - Heating resistance type air flow rate measuring apparatus - Google Patents
Heating resistance type air flow rate measuring apparatusInfo
- Publication number
- JP2000162011A JP2000162011A JP10341337A JP34133798A JP2000162011A JP 2000162011 A JP2000162011 A JP 2000162011A JP 10341337 A JP10341337 A JP 10341337A JP 34133798 A JP34133798 A JP 34133798A JP 2000162011 A JP2000162011 A JP 2000162011A
- Authority
- JP
- Japan
- Prior art keywords
- intake air
- conductive support
- support member
- air temperature
- heat
- 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.)
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Links
Landscapes
- Measuring Volume Flow (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、空気流量及び空気
温度を測定する空気流量測定装置に係り、特に自動車の
エンジンに吸入される吸入空気流量及び吸入空気温度を
測定するのに適する発熱抵抗式空気流量測定装置に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air flow rate measuring device for measuring an air flow rate and an air temperature, and more particularly to a heating resistance type suitable for measuring an intake air flow rate and an intake air temperature taken into an automobile engine. The present invention relates to an air flow measuring device.
【０００２】[0002]
【従来の技術】従来の吸気温度検出装置を備えた発熱抵
抗式空気流量測定装置は、例えば特開平8−145757 号公
報に記載されているような構造をしており、本発明と同
等の構成であるが、本発明の主旨である、吸入空気温度
検出素子の壁温特性を向上させる構造については記載さ
れていない。2. Description of the Related Art A conventional heating resistance type air flow measuring device provided with an intake air temperature detecting device has a structure as described, for example, in Japanese Patent Application Laid-Open No. 8-147557, and has the same structure as that of the present invention. However, there is no description of a structure that improves the wall temperature characteristic of the intake air temperature detecting element, which is the gist of the present invention.
【０００３】[0003]
【発明が解決しようとする課題】上記従来技術では、他
の熱源の影響によりモジュールが高温になったとき、そ
の温度が絶縁性支持部材，導電性支持部材を伝わり吸入
空気温度検出素子に影響を及ぼし、正確な吸入空気温度
を検出できず、壁温特性が問題となり、しいては内燃機
関の制御に悪影響を及ぼすことになる。In the above prior art, when the temperature of the module becomes high due to the influence of another heat source, the temperature is transmitted through the insulating support member and the conductive support member to affect the intake air temperature detecting element. As a result, an accurate intake air temperature cannot be detected, and the wall temperature characteristic becomes a problem, which adversely affects the control of the internal combustion engine.
【０００４】本発明の目的は、吸入空気温度検出素子の
壁温特性を向上させる構造を備えた発熱抵抗式空気流量
測定装置を提供することにある。An object of the present invention is to provide a heating resistance type air flow measuring device having a structure for improving the wall temperature characteristics of an intake air temperature detecting element.
【０００５】[0005]
【課題を解決するための手段】上記問題を解決するため
に、吸入空気温度検出素子を固定する導電性支持部材を
吸入空気に対してオフセットさせること、また導電性支
持部材間で吸入空気温度検出素子をオフセットさせるこ
とで、吸入空気に対し下流側に配置された導電性支持部
材へ伝わる熱を低減することができ、また吸入空気温度
検出素子の温度上昇を低減することで、壁温特性の優れ
た吸入空気温度検出装置を備えた発熱抵抗式空気流量測
定装置を提供できる。In order to solve the above problems, a conductive support member for fixing an intake air temperature detecting element is offset with respect to intake air, and an intake air temperature is detected between the conductive support members. By offsetting the elements, the heat transmitted to the conductive support member disposed downstream with respect to the intake air can be reduced, and the rise in the temperature of the intake air temperature detection element can be reduced to reduce the wall temperature characteristics. It is possible to provide a heating resistance type air flow measuring device equipped with an excellent intake air temperature detecting device.
【０００６】[0006]
【発明の実施の形態】以下、本発明の実施例を図１から
図７を用いて説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.
【０００７】図１は本発明の第一の実施例である発熱抵
抗式空気流量測定装置の正面図、図２は発熱抵抗式空気
流量測定装置の縦断面図であり、図３（ａ)，(ｂ）及び
図６（ａ)，(ｂ）に吸気温度検出素子部分の拡大図を示
す。FIG. 1 is a front view of a heating resistance type air flow measuring device according to a first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of the heating resistance type air flow measuring device. 6 (b) and FIGS. 6 (a) and 6 (b) are enlarged views of the intake air temperature detecting element.
【０００８】内燃機関の吸入空気通路を構成するボディ
４が形成する主通路５の内部に副通路６が位置するよう
に、ボディ４の外壁面に電子回路１０を内蔵するモジュ
ール１１が固定されている。発熱抵抗体７及び感温抵抗
体８は副通路６の内部に配置され、導電性支持部材９に
溶接等により固定されている。また、導電性支持部材９
は、発熱抵抗体７及び感温抵抗体８の固定部である絶縁
性支持部材３からモジュール１１の内部まで連通してい
る。さらに、吸入空気温度検出素子２は吸入空気温度検
出素子リード部材２ａを上流側導電性支持部材１ａ及び
下流側導電性支持部材１ｂに溶接等で固定され、主通路
５内に配置されている。A module 11 containing an electronic circuit 10 is fixed on the outer wall of the body 4 so that the sub-passage 6 is located inside the main passage 5 formed by the body 4 constituting the intake air passage of the internal combustion engine. I have. The heating resistor 7 and the temperature-sensitive resistor 8 are disposed inside the auxiliary passage 6 and are fixed to the conductive support member 9 by welding or the like. Further, the conductive support member 9
Communicates from the insulating support member 3, which is a fixing portion of the heating resistor 7 and the temperature-sensitive resistor 8, to the inside of the module 11. Further, the intake air temperature detection element 2 has the intake air temperature detection element lead member 2a fixed to the upstream conductive support member 1a and the downstream conductive support member 1b by welding or the like, and is disposed in the main passage 5.
【０００９】本発明は吸入空気温度検出素子２の壁温特
性を向上させる構造を備えた発熱抵抗式空気流量測定装
置を提供することを目的としたものである。An object of the present invention is to provide a heating resistance type air flow measuring device having a structure for improving the wall temperature characteristics of the intake air temperature detecting element 2.
【００１０】まず、吸入空気温度検出素子２の壁温特性
について説明する。モジュール１１が例えば他の発熱体
などからの影響により高温になると、その熱が絶縁性支
持部材３，上流側導電性支持部材１ａ及び下流側導電性
支持部材１ｂを伝わり、吸入空気温度検出素子２に達
し、実際の吸入空気温度とモジュール側からの熱を加え
た温度を検出することになる。このモジュール側からの
熱つまり壁温の影響を壁温特性と呼び、その影響が小さ
いほど壁温特性は良いとされる。First, the wall temperature characteristics of the intake air temperature detecting element 2 will be described. When the temperature of the module 11 becomes high due to, for example, another heating element, the heat is transmitted through the insulating support member 3, the upstream conductive support member 1a and the downstream conductive support member 1b, and the intake air temperature detecting element 2 , And the temperature obtained by adding the actual intake air temperature and the heat from the module side is detected. The influence of the heat from the module side, that is, the wall temperature is called a wall temperature characteristic, and the smaller the influence is, the better the wall temperature characteristic is.
【００１１】従来の構造では、吸入空気温度検出素子２
を固定する上流側導電性支持部材１ａ及び下流側導電性
支持部材１ｂは吸入空気に対し平行で、且つ同一線上に
あったため、壁温度が各導電性支持部材に達したとき、
上流側導電性支持部材１ａには吸入空気が直接当り冷却
されるが、下流側導電性支持部材１ｂには直接吸入空気
が当たらず冷却されにくい。さらには上流側導電性支持
部材１ａ自体が有する熱によって下流側導電性支持部材
１ｂが暖められる構造になっていた。In the conventional structure, the intake air temperature detecting element 2
Since the upstream-side conductive support member 1a and the downstream-side conductive support member 1b for fixing are parallel to the intake air and on the same line, when the wall temperature reaches each conductive support member,
Although the intake air directly hits the upstream conductive support member 1a and is cooled, the intake air does not directly hit the downstream conductive support member 1b and is hardly cooled. Further, the downstream conductive support member 1b is heated by the heat of the upstream conductive support member 1a itself.
【００１２】本発明は、上流側導電性支持部材１ａ及び
下流側導電性支持部材ｂを吸入空気に対して、オフセッ
ト配置させる構造にするものである。この構造にするこ
とにより、吸入空気により下流側導電性支持部材１ｂは
上流側導電性支持部材１ａが冷却されると同等に冷却さ
れ、また、上流側導電性支持部材１ａの有する熱が空気
を介して伝わる熱も低減することができ、吸入空気温度
検出素子２へ伝達される壁温を低減することができる。
また、オフセットさせる導電性支持部材は上流側下流側
どちらでも同様の効果が得られる。The present invention has a structure in which the upstream conductive support member 1a and the downstream conductive support member b are offset from the intake air. With this structure, the downstream conductive support member 1b is cooled by the intake air in the same manner as the upstream conductive support member 1a is cooled, and the heat of the upstream conductive support member 1a removes air. Thus, the heat transmitted through the intake air temperature detecting element 2 can be reduced.
The same effect can be obtained on the conductive support member to be offset on both the upstream side and the downstream side.
【００１３】さらに、図５（ａ)，(ｂ）に示すような吸
入空気検出素子２支持構造においても、図６（ａ)，
(ｂ）のように本発明を適応させることで、壁温特性を
向上させる効果を得ることができる。Furthermore, in the intake air detecting element 2 support structure as shown in FIGS. 5 (a) and 5 (b), FIGS.
By applying the present invention as in (b), the effect of improving the wall temperature characteristics can be obtained.
【００１４】次に本発明の第二の実施例を図４（ａ)，
(ｂ）で説明する。Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described in (b).
【００１５】壁温特性の悪化の原因の一つである下流側
導電性支持部材１ｂが上流側導電性支持部材１ａよりも
高温になってしまうことである。本発明では、この温度
差を低減するため、両支持体間において従来中間に配置
されるようになっていた吸入空気温度検出素子２を上流
側導電性支持部材１ａ側に大きく偏心させて配置させる
構造にするものである。One of the causes of the deterioration of the wall temperature characteristic is that the temperature of the downstream conductive support member 1b becomes higher than that of the upstream conductive support member 1a. In the present invention, in order to reduce this temperature difference, the intake air temperature detecting element 2 which has been conventionally arranged between the two supports is disposed so as to be largely eccentric toward the upstream conductive support member 1a. It is a structure.
【００１６】従来、吸入空気温度検出素子２は、例えば
溶接などにより導電性支持部材間の中心に位置するよう
に接続されていたが、このとき吸入空気温度検出素子２
は製造バラツキなどの範囲で偏りが生じることになる。
前記バラツキ範囲の偏りでは壁温影響を低減するまでに
至らない。Conventionally, the intake air temperature detecting element 2 has been connected so as to be located at the center between the conductive support members by, for example, welding or the like.
Will be biased in a range such as manufacturing variation.
The deviation in the variation range does not lead to the reduction of the wall temperature effect.
【００１７】本発明は、これらのバラツキ範囲以上に吸
入空気温度検出素子２を偏心させることで、壁温特性を
低減できることを特徴としている。これにより下流側導
電性支持部材１ｂから吸入空気温度検出素子２へ伝達さ
れる熱が空気へ放熱される面積が確保でき、吸入空気温
度検出素子２の壁温特性を向上させることができる。次
に本発明の第三の実施例を図５及び図７で説明する。The present invention is characterized in that the wall temperature characteristic can be reduced by eccentricizing the intake air temperature detecting element 2 beyond the above-mentioned variation range. Thus, an area where heat transmitted from the downstream conductive support member 1b to the intake air temperature detection element 2 is radiated to the air can be secured, and the wall temperature characteristics of the intake air temperature detection element 2 can be improved. Next, a third embodiment of the present invention will be described with reference to FIGS.
【００１８】吸入空気温度検出素子２支持構造が図５に
示すような構造の場合、吸入空気温度検出素子２を上流
側に偏心させることはできないので、壁温による吸入空
気温度検出素子２の温度上昇をより避けるように、壁か
ら遠ざけて配置するものである。このような構造にする
ことで、壁温特性の優れた吸入空気温度検出装置を備え
た発熱抵抗式空気流量測定装置を提供できる。In the case where the intake air temperature detecting element 2 has a structure as shown in FIG. 5, the intake air temperature detecting element 2 cannot be eccentric to the upstream side. It is placed away from the wall to avoid ascent. With such a structure, it is possible to provide a heating resistance type air flow measuring device provided with an intake air temperature detecting device having excellent wall temperature characteristics.
【００１９】さらに、上記実施例の組み合わせにより更
なる壁温特性の向上が可能になる。Further, the combination of the above embodiments makes it possible to further improve the wall temperature characteristics.
【００２０】[0020]
【発明の効果】本発明によれば、吸入空気温度検出素子
支持構造において、上流側導電性支持部材と下流側導電
性支持部材をオフセットさせること、また、導電性支持
部材間に配置される吸入空気温度検出素子を上流側導電
性支持部材側に大きく偏心させて配置させることによっ
て、壁温特性の優れた吸入空気温度検出装置を備えた発
熱抵抗式空気流量測定装置を提供できる。According to the present invention, in the intake air temperature detecting element support structure, the upstream conductive support member and the downstream conductive support member are offset, and the suction member is disposed between the conductive support members. By arranging the air temperature detecting element to be largely eccentric on the upstream conductive support member side, it is possible to provide a heating resistance type air flow measuring device including an intake air temperature detecting device having excellent wall temperature characteristics.
【図１】本発明の第一の実施例を示す発熱抵抗式空気流
量測定装置の正面図。FIG. 1 is a front view of a heating resistance type air flow measuring device showing a first embodiment of the present invention.
【図２】本発明の第一の実施例を示す発熱抵抗式空気流
量測定装置の縦断面図。FIG. 2 is a longitudinal sectional view of a heating resistance type air flow measuring device showing a first embodiment of the present invention.
【図３】（ａ）及び（ｂ）は第一の実施例を示す吸入空
気温度検出素子支持部の拡大した正面図及び同図（ａ）
の側断面図。FIGS. 3 (a) and (b) are enlarged front views of the intake air temperature detecting element supporting portion and the same view (a) showing the first embodiment.
FIG.
【図４】（ａ）及び（ｂ）は第二の実施例を示す吸入空
気温度検出素子支持部の拡大した正面図及び同図（ａ）
の側断面図。4 (a) and 4 (b) are enlarged front views of an intake air temperature detecting element support portion showing a second embodiment and FIGS. 4 (a) and 4 (b).
FIG.
【図５】（ａ）及び（ｂ）は他の吸入空気温度検出素子
支持部の拡大した正面図及び同図（ａ）の側断面図。5 (a) and 5 (b) are an enlarged front view of another intake air temperature detecting element supporting portion and a side sectional view of FIG. 5 (a).
【図６】（ａ）及び（ｂ）は第一の実施例を示す吸入空
気温度検出素子支持部の拡大した正面図及び同図（ａ）
の側断面図。FIGS. 6 (a) and (b) are enlarged front views of the intake air temperature detecting element support portion showing the first embodiment and FIGS.
FIG.
【図７】（ａ）及び（ｂ）は第三の実施例を示す吸入空
気温度検出素子支持部の拡大した正面図及び同図（ａ）
の側断面図。FIGS. 7 (a) and 7 (b) are enlarged front views of an intake air temperature detecting element support portion showing a third embodiment and FIGS. 7 (a) and 7 (b).
FIG.
１ａ…上流側導電性支持部材、１ｂ…下流側導電性支持
部材、２…吸入空気温度検出素子、２ａ…吸入空気温度
検出素子リード部材、３…絶縁性支持部材、４…ボデ
ィ、５…主通路、６…副通路、７…発熱抵抗体、８…感
温抵抗体、９…導電性支持部材、１０…回路基板、１１
…モジュール。1a ... upstream conductive support member, 1b ... downstream conductive support member, 2 ... intake air temperature detection element, 2a ... intake air temperature detection element lead member, 3 ... insulating support member, 4 ... body, 5 ... main Passageway 6 Sub-passageway 7 Heating resistor 8 Temperature sensing resistor 9 Conductive support member 10 Circuit board 11
…module.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 五十嵐 信弥 茨城県ひたちなか市高場2477番地 株式会 社日立カーエンジニアリング内 Ｆターム(参考） 2F035 AA02 EA04 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shinya Igarashi 2477 Takaba, Hitachinaka-shi, Ibaraki F-term in Hitachi Car Engineering Co., Ltd. 2F035 AA02 EA04
Claims (3)
抗体及び感温抵抗体と、前記発熱抵抗体及び感温抵抗体
と電気的に接続され、前記発熱抵抗体からの放熱量を基
に空気の流量に対応した信号を出力する電子回路，吸入
空気温度検出素子及び前記吸入空気温度検出素子を電気
的に接続し支持する導電性支持体を有する発熱抵抗式空
気流量測定装置において、前記導電性支持部材に吸入空
気が阻害されずに導かれるスペースを確保すると共に、
前記吸入空気温度検出素子両端の前記導電性支持部材が
吸入空気の上流から見て重ならないように前記導電性支
持部材の幅以上オフセットさせたことを特徴とする発熱
抵抗式空気流量測定装置。1. A heating resistor and a temperature-sensitive resistor disposed in an air passage of an internal combustion engine, and electrically connected to the heating resistor and the temperature-sensitive resistor, and dissipating heat from the heating resistor. An electronic circuit for outputting a signal corresponding to the flow rate of air, an intake air temperature detection element, and a heating resistance type air flow measurement apparatus having a conductive support for electrically connecting and supporting the intake air temperature detection element. Along with securing a space where the intake air is guided without being disturbed by the conductive support member,
A heating resistance type air flow measuring device, characterized in that the conductive support members at both ends of the intake air temperature detecting element are offset by the width of the conductive support member so as not to overlap when viewed from upstream of the intake air.
抗体及び感温抵抗体と、前記発熱抵抗体及び感温抵抗体
と電気的に接続され、前記発熱抵抗体からの放熱量を基
に空気の流量に対応した信号を出力する電子回路，吸入
空気温度検出素子及び前記吸入空気温度検出素子を電気
的に接続し支持する導電性支持部材を有する発熱抵抗式
空気流量測定装置において、前記導電性支持部材に吸入
空気が阻害されずに導かれるスペースを確保すると共
に、前記吸入空気温度検出素子が前記導電性支持部材間
で上流側にオフセットさせ設置させたことを特徴とする
発熱抵抗式空気流量測定装置。2. A heat-generating resistor and a temperature-sensitive resistor disposed in an air passage of an internal combustion engine, and electrically connected to the heat-generating resistor and the temperature-sensitive resistor. An electronic circuit for outputting a signal corresponding to a flow rate of air, an intake air temperature detection element, and a heating resistance type air flow measurement apparatus having a conductive support member for electrically connecting and supporting the intake air temperature detection element. A heat generating resistor, wherein a space is provided for the conductive support member to guide the intake air without being hindered, and the intake air temperature detecting element is offset and installed upstream between the conductive support members. Type air flow measuring device.
抗体及び感温抵抗体と、前記発熱抵抗体及び感温抵抗体
と電気的に接続され、前記発熱抵抗体からの放熱量を基
に空気の流量に対応した信号を出力する電子回路，吸入
空気温度検出素子及び前記吸入空気温度検出素子を電気
的に接続し支持する導電性支持部材を有する発熱抵抗式
空気流量測定装置において、前記導電性支持部材に吸入
空気が阻害されずに導かれるスペースを確保すると共
に、前記吸入空気温度検出素子が前記導電性支持部材間
で前記導電性支持部材を伝わる熱を受けにくい方向にオ
フセットさせ設置させたことを特徴とする発熱抵抗式空
気流量測定装置。3. A heat-generating resistor and a temperature-sensitive resistor disposed in an air passage of an internal combustion engine, and electrically connected to the heat-generating resistor and the temperature-sensitive resistor. An electronic circuit for outputting a signal corresponding to a flow rate of air, an intake air temperature detection element, and a heating resistance type air flow measurement apparatus having a conductive support member for electrically connecting and supporting the intake air temperature detection element. The conductive support member secures a space in which the intake air is guided without being disturbed, and the intake air temperature detecting element is offset between the conductive support members in a direction that is less likely to receive heat transmitted through the conductive support member. A heating resistance type air flow measuring device characterized by being installed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10341337A JP2000162011A (en) | 1998-12-01 | 1998-12-01 | Heating resistance type air flow rate measuring apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10341337A JP2000162011A (en) | 1998-12-01 | 1998-12-01 | Heating resistance type air flow rate measuring apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000162011A true JP2000162011A (en) | 2000-06-16 |
Family
ID=18345287
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10341337A Pending JP2000162011A (en) | 1998-12-01 | 1998-12-01 | Heating resistance type air flow rate measuring apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000162011A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011085542A (en) * | 2009-10-19 | 2011-04-28 | Mitsubishi Electric Corp | Device for measuring flow rate |
| JP2012047660A (en) * | 2010-08-30 | 2012-03-08 | Hitachi Automotive Systems Ltd | Thermal flow rate sensor |
-
1998
- 1998-12-01 JP JP10341337A patent/JP2000162011A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011085542A (en) * | 2009-10-19 | 2011-04-28 | Mitsubishi Electric Corp | Device for measuring flow rate |
| US8037751B2 (en) | 2009-10-19 | 2011-10-18 | Mitsubishi Electric Corporation | Flow rate measuring apparatus |
| DE102010019303B4 (en) * | 2009-10-19 | 2014-07-17 | Mitsubishi Electric Corp. | Flow rate measuring device |
| JP2012047660A (en) * | 2010-08-30 | 2012-03-08 | Hitachi Automotive Systems Ltd | Thermal flow rate sensor |
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