JPH0552623A - Air flowmeter - Google Patents
Air flowmeterInfo
- Publication number
- JPH0552623A JPH0552623A JP3213376A JP21337691A JPH0552623A JP H0552623 A JPH0552623 A JP H0552623A JP 3213376 A JP3213376 A JP 3213376A JP 21337691 A JP21337691 A JP 21337691A JP H0552623 A JPH0552623 A JP H0552623A
- Authority
- JP
- Japan
- Prior art keywords
- intake
- air flow
- heat
- flow rate
- detecting element
- 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.)
- Pending
Links
Landscapes
- Measuring Volume Flow (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は空気流量計における発熱
型空気流量検出素子の構造に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a heat generating type air flow rate detecting element in an air flow meter.
【０００２】[0002]
【従来の技術】従来の発熱型空気流量検出素子の構造と
しては、特開昭57−156523号，特開昭58−95265号，特
開昭60−60521号に記載が見られるが、前記従来技術で
は、発熱型空気流量検出素子の吸気上流側と吸気下流側
の放出熱量に差を持たせる構造は規定していない。2. Description of the Related Art Regarding the structure of a conventional heat-generating type air flow rate detecting element, there are described in JP-A-57-156523, JP-A-58-95265 and JP-A-60-60521. The technology does not stipulate a structure in which the heat release type air flow rate detection element has a difference in the amount of heat released from the intake upstream side and the intake downstream side.
【０００３】[0003]
【発明が解決しようとする課題】上記従来技術は、発熱
型空気流量検出素子の吸気上流側と吸気下流側の放出熱
量については考慮が為されておらず、内燃機関の吸気弁
開閉などに起因する、吸気系下流側から伝播する吸気脈
動の影響を受けやすかった。吸気脈動は内燃機関の実吸
入空気量には影響を及ぼすことは無く、空気流量検出素
子が吸気脈動の影響を受けると空気流量計の出力が実吸
入空気量とは異なる値を示し、出力特性精度悪化の原因
と成っていた。In the above-mentioned prior art, the amount of heat released from the heat-generating type air flow rate detecting element on the intake upstream side and the intake downstream side is not taken into consideration. However, it was easily affected by the intake pulsation propagating from the downstream side of the intake system. The intake pulsation does not affect the actual intake air amount of the internal combustion engine, and when the air flow rate detection element is affected by the intake pulsation, the output of the air flow meter shows a value different from the actual intake air amount. It was the cause of the deterioration of accuracy.
【０００４】本発明は、発熱型空気流量検出素子を改良
することにより、吸気系下流側から伝般する吸気脈動の
影響を低減し、内燃機関の全ての運転条件に於いて精度
の良い出力特性が得られる空気流量計を提供することを
目的とする。By improving the heat generation type air flow rate detecting element, the present invention reduces the influence of intake pulsation transmitted from the downstream side of the intake system, and provides accurate output characteristics under all operating conditions of the internal combustion engine. It is an object of the present invention to provide an air flow meter that can obtain
【０００５】[0005]
【課題を解決するための手段】上記目的を達成するため
に、発熱型空気流量検出素子の、素子全体をコーティン
グする耐熱絶縁材料の厚さを吸気上流側と吸気下流側で
変える事により、発熱型空気流量検出素子の吸気上流側
と吸気下流側の放出熱量に差を持たせたものである。In order to achieve the above object, heat generation is achieved by changing the thickness of the heat-resistant insulating material coating the entire heat-generating air flow rate detection element between the intake upstream side and the intake downstream side. The amount of heat released from the upstream side of the intake air and the amount of heat released from the downstream side of the intake air of the die air flow rate detection element are made different from each other.
【０００６】また、上記目的を達成する他の手段とし
て、発熱型空気流量検出素子の、絶縁材料により形成さ
れる管状ボビンの形状を、円筒以外の形状として、発熱
型空気流量検出素子の吸気上流側と吸気下流側の放出熱
量に差を持たせたものである。また、上記目的を達成す
る他の手段として、発熱型空気流量検出素子の、ボビン
表面に形成される発熱抵抗体を吸気下流側のみ絶縁材料
により形成される管状ボビンの内部に埋め込む事によ
り、発熱型空気流量検出素子の吸気上流側と吸気下流側
の放出熱量に差を持たせたものである。Further, as another means for achieving the above object, the tubular bobbin of the heat generating air flow rate detecting element is made of an insulating material, and the shape of the tubular bobbin is other than a cylinder. The difference in the amount of heat released between the intake side and the intake downstream side. In addition, as another means for achieving the above-mentioned object, by embedding a heating resistor formed on the bobbin surface of the heating type air flow rate detecting element inside a tubular bobbin formed of an insulating material only on the intake air downstream side, heat is generated. The amount of heat released from the upstream side of the intake air and the amount of heat released from the downstream side of the intake air of the die air flow rate detection element are made different from each other.
【０００７】[0007]
【作用】発熱型空気流量検出素子の、吸気上流側の放出
熱量を大きく、吸気下流側の放出熱量を小さくする事に
より、吸気上流側からの吸入空気量に対しては、前記従
来技術と同等の感度を示し、吸気下流側から伝般する吸
気脈動等に対しては感度を低下させることが出来る為、
内燃機関の全ての運転条件に於いて吸気脈動の影響を受
けない実吸入空気量を測定することが可能と成る。[Function] By increasing the amount of heat released on the upstream side of the intake air and decreasing the amount of heat released on the downstream side of the intake air of the heat generation type air flow rate detection element, the intake air amount from the upstream side of the intake air is equal to that of the prior art. Since it shows the sensitivity of, and the sensitivity can be lowered for the intake pulsation etc. transmitted from the intake downstream side,
It becomes possible to measure the actual intake air amount that is not affected by the intake pulsation under all operating conditions of the internal combustion engine.
【０００８】[0008]
【実施例】以下、本発明の一実施例を図１により説明す
る。絶縁材料により形成される管状ボビン１に、導電性
部材によるリード４が挿入される。また、管状ボビン１
には発熱抵抗体２が巻かれ、耐熱絶縁材料３によりコー
ティングし、発熱型空気流量検出素子を構成している。
本実施例によれば、耐熱絶縁材料３の厚さを吸気上流側
と吸気下流側で変え、吸気上流側を薄く，吸気下流側を
厚くすることにより、吸気下流側の放出熱量を吸気上流
側に対し小さくすることが出来る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. The lead 4 made of a conductive member is inserted into the tubular bobbin 1 made of an insulating material. Also, tubular bobbin 1
A heat generating resistor 2 is wound around and is coated with a heat resistant insulating material 3 to form a heat generating type air flow rate detecting element.
According to the present embodiment, the thickness of the heat-resistant insulating material 3 is changed between the intake upstream side and the intake downstream side, and the intake upstream side is made thin and the intake downstream side is made thick, so that the amount of heat released from the intake downstream side is increased. Can be made smaller.
【０００９】図２により、熱線式空気流量計の構成を説
明する。上方より流入した吸入空気はボディ５により構
成される吸気通路を通過する。吸入空気流量は発熱型空
気流量検出素子６，温度補償用感温抵抗素子７により検
出され、また発熱型空気流量検出素子６，温度補償用感
温抵抗素子７は駆動用回路を有するモジュール８により
駆動される。The construction of the hot wire type air flow meter will be described with reference to FIG. The intake air that has flowed in from above passes through the intake passage formed by the body 5. The intake air flow rate is detected by the heat generation type air flow rate detection element 6 and the temperature compensation temperature sensitive resistance element 7, and the heat generation type air flow rate detection element 6 and the temperature compensation temperature sensitive resistance element 7 are detected by the module 8 having a drive circuit. Driven.
【００１０】本発明の他の実施例を図３により説明す
る。本実施例では絶縁材料により形成される管状ボビン
１の形状を円筒以外とし、吸気下流側の放出熱量を小さ
くする。図３に示す形状では底辺の部分で空気流が剥離
を起こすため吸気下流側にあたる空気流が減少する。以
上により、吸気下流側の放熱量を吸気上流側に対し小さ
くすることが出来る。Another embodiment of the present invention will be described with reference to FIG. In the present embodiment, the tubular bobbin 1 formed of an insulating material has a shape other than a cylinder to reduce the amount of heat released on the intake air downstream side. In the shape shown in FIG. 3, since the air flow separates at the bottom, the air flow on the downstream side of the intake air decreases. As described above, the heat radiation amount on the intake downstream side can be made smaller than that on the intake upstream side.
【００１１】本発明の他の実施例を図４により説明す
る。本実施例では、管状ボビン１の吸気下流側に溝を設
け、その中に発熱抵抗体２を挿入する事により、吸気下
流側の放出熱量を吸気上流側に対し小さくしている。Another embodiment of the present invention will be described with reference to FIG. In this embodiment, a groove is provided on the downstream side of the intake air of the tubular bobbin 1 and the heating resistor 2 is inserted into the groove to reduce the amount of heat released on the downstream side of the intake air compared to the upstream side of the intake air.
【００１２】[0012]
【発明の効果】本発明によれば、発熱型空気流量検出素
子の吸入空気流量に対する感度が吸気上流側と、吸気下
流側で差があり、吸気下流側では鈍感になっているた
め、吸気下流側から伝般する吸気脈動等に対しては感度
を低下させることが出来る。また吸気上流側の感度は従
来技術と同等としているため、吸入空気量に対する感度
は従来技術と同等である。以上の効果により、本発明に
よる空気流量計は、内燃機関の全ての運転条件に於いて
吸気脈動の影響を受ける事無く、実吸入空気量を測定す
ることが可能と成る。According to the present invention, the sensitivity of the heat generation type air flow rate detection element to the intake air flow rate differs between the intake upstream side and the intake downstream side, and is insensitive on the intake downstream side. It is possible to reduce the sensitivity to the intake pulsation transmitted from the side. Further, since the sensitivity on the upstream side of the intake air is the same as that of the conventional technology, the sensitivity to the intake air amount is the same as that of the conventional technology. With the above effects, the air flow meter according to the present invention can measure the actual intake air amount without being affected by the intake pulsation under all operating conditions of the internal combustion engine.
【図１】本発明の一実施例である巻線式発熱型空気流量
検出素子の斜視図及び断面図である。FIG. 1 is a perspective view and a cross-sectional view of a wire-wound heat generation type air flow rate detection element according to an embodiment of the present invention.
【図２】本発明の発熱型空気流量検出素子を有する、空
気流量計の一例を示す図である。FIG. 2 is a diagram showing an example of an air flow meter having a heat generation type air flow rate detection element of the present invention.
【図３】本発明の一実施例である巻線式発熱型空気流量
検出素子の断面図である。FIG. 3 is a cross-sectional view of a wire-wound heat generation type air flow rate detection element according to an embodiment of the present invention.
【図４】本発明の一実施例である巻線式発熱型空気流量
検出素子の断面図である。FIG. 4 is a cross-sectional view of a wire-wound heat generation type air flow rate detection element according to an embodiment of the present invention.
１…管状ボビン、２…発熱抵抗体、３…コーティング
材、４…リード、５…ボディ、６…発熱型空気流量検出
素子、７…温度補償用感温抵抗素子、８…駆動用モジュ
ール。DESCRIPTION OF SYMBOLS 1 ... Tubular bobbin, 2 ... Heating resistor, 3 ... Coating material, 4 ... Lead, 5 ... Body, 6 ... Exothermic type air flow rate detection element, 7 ... Temperature compensation temperature-sensitive resistance element, 8 ... Driving module.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 小林 千尋 茨城県勝田市大字高場2520番地 株式会社 日立製作所自動車機器事業部内 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Chihiro Kobayashi 2520 Takaba, Katsuta City, Ibaraki Prefecture Hitachi Ltd. Automotive Equipment Division
Claims (4)
た発熱型空気流量検出素子と吸気通路を形成するボディ
及び、前記発熱型空気流量検出素子を定められた温度に
加熱するとともに、該当熱電圧を吸入空気流量に対応し
た出力電圧信号に変換する駆動回路から成る空気流量計
に於いて、絶縁材料により形成される管状ボビンと、ボ
ビンに挿入接着される導電性部材によるリードとボビン
表面に形成される発熱抵抗体と素子全体をコーティング
する耐熱絶縁材料からなる発熱型空気流量検出素子に於
いて、発熱型空気流量検出素子の吸気上流側と吸気下流
側の放出熱量に差を持たせた事を特徴とする空気流量
計。1. A body for forming a heat generating type air flow rate detecting element and an air intake path installed in an air passage of an intake system of an internal combustion engine, and heating the heat generating type air flow rate detecting element to a predetermined temperature, In an air flow meter comprising a drive circuit for converting a corresponding heat voltage into an output voltage signal corresponding to an intake air flow rate, a tubular bobbin formed of an insulating material, and a lead and a bobbin formed by a conductive member inserted and bonded to the bobbin. In a heat-generating air flow rate detection element consisting of a heat-generating resistor formed on the surface and a heat-resistant insulating material that coats the entire element, there is a difference in the amount of heat released on the upstream side and the intake side of the heat-generating air flow rate detection element. An air flow meter characterized by the fact that it is made.
ーティングする耐熱絶縁材料の厚さを吸気上流側と吸気
下流側で変える事により、発熱型空気流量検出素子の吸
気上流側と吸気下流側の放出熱量に差を持たせたことを
特徴とする請求項１記載の空気流量計。2. A heat-generating air flow rate detecting element, wherein the thickness of a heat-resistant insulating material coating the entire element is changed between the intake upstream side and the intake downstream side, whereby the intake upstream side and the intake downstream side of the heat generating type air flow rate detecting element. The air flow meter according to claim 1, wherein the amount of heat released on the side is made different.
り形成される管状ボビンの形状を、円筒以外の形状とし
て、発熱型空気流量検出素子の吸気上流側と吸気下流側
の放出熱量に差を持たせたことを特徴とする請求項１記
載の空気流量計。3. A tubular bobbin formed of an insulating material in the heat generating type air flow rate detecting element has a shape other than a cylinder, and the heat releasing type air flow rate detecting element has a difference in heat release amount between the intake upstream side and the intake downstream side. The air flow meter according to claim 1, further comprising:
形成される発熱抵抗体を吸気下流側のみ絶縁材料により
形成される管状ボビンの内部に埋め込む事により、発熱
型空気流量検出素子の吸気上流側と吸気下流側の放出熱
量に差を持たせたことを特徴とする請求項１記載の空気
流量計。4. An air intake of the heat generating type air flow rate detecting element by embedding a heat generating resistor formed on the surface of the bobbin of the heat generating type air flow rate detecting element into a tubular bobbin formed of an insulating material only on the intake side downstream side. The air flow meter according to claim 1, wherein the amount of heat released on the upstream side and the amount of heat released on the downstream side of the intake air are made different from each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3213376A JPH0552623A (en) | 1991-08-26 | 1991-08-26 | Air flowmeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3213376A JPH0552623A (en) | 1991-08-26 | 1991-08-26 | Air flowmeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0552623A true JPH0552623A (en) | 1993-03-02 |
Family
ID=16638170
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3213376A Pending JPH0552623A (en) | 1991-08-26 | 1991-08-26 | Air flowmeter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0552623A (en) |
-
1991
- 1991-08-26 JP JP3213376A patent/JPH0552623A/en active Pending
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