JPS63128221U

JPS63128221U -

Info

Publication number: JPS63128221U
Application number: JP1996787U
Authority: JP
Priority date: 1987-02-16
Filing date: 1987-02-16
Publication date: 1988-08-22

Description

[Brief explanation of the drawing]

第１図は本考案の構成を説明するための全体ブ
ロツク図、第２図はシングルＯ_２センサシステム
およびダブルＯ_２センサシステムを説明する排気
エミツシヨン特性図、第３図は本考案に係る内燃
機関の空燃比制御装置の一実施例を示す全体概略
図、第４図は触媒劣化前のＯ_２センサ出力特性図
、第５図は触媒劣化後のＯ_２センサ出力特性図、
第６図、第８図、第９図、第１０図、第１２図、
第１３図は第３図の制御回路の動作を説明するた
めのフローチヤート、第７図は第６図のフローチ
ヤートを補足説明するためのタイミング図、第１
１図は第１０図のフローチヤートを補足説明する
ためのタイミング図である。１……機関本体、３……エアフローメータ、４
……デイストリビユータ、５，６……クランク角
センサ、１０……制御回路、１２……触媒コンバ
ータ、１３……上流側（第１の）Ｏ_２センサ、１
５……下流側（第２の）Ｏ_２センサ、１６……ア
ラーム、１７……スイツチ。 Fig. 1 is an overall block diagram for explaining the configuration of the present invention, Fig. 2 is an exhaust emission characteristic diagram for explaining a single O ₂ sensor system and a double O ₂ sensor system, and Fig. 3 is an internal combustion engine according to the present invention. 4 is an O ₂ sensor output characteristic diagram before catalyst deterioration, and FIG. 5 is an O ₂ sensor output characteristic diagram after catalyst deterioration.
Figure 6, Figure 8, Figure 9, Figure 10, Figure 12,
13 is a flowchart for explaining the operation of the control circuit in FIG. 3, FIG. 7 is a timing diagram for supplementary explanation of the flowchart in FIG. 6, and FIG.
FIG. 1 is a timing diagram for supplementary explanation of the flowchart of FIG. 10. 1... Engine body, 3... Air flow meter, 4
... Distributor, 5, 6 ... Crank angle sensor, 10 ... Control circuit, 12 ... Catalytic converter, 13 ... Upstream side (first) O ₂ sensor, 1
5...Downstream (second) _O2 sensor, 16...Alarm, 17...Switch.

補正昭６２．４．２８図面の簡単な説明を次のように補正する。明細書第３９頁５行目「第１２図」を「第１２
図Ａ、第１２図Ｂ」と補正する。明細書第３９頁第１１行目「である。」を「、
第１２図は第１２図Ａ、第１２図Ｂの結合を示す
図である。」と補正する。Amendment April 28, 1982 The brief description of the drawing is amended as follows. "Figure 12" on page 39, line 5 of the specification is replaced with "Figure 12".
Figure A, Figure 12 B. On page 39, line 11 of the specification, “is” is replaced with “,”
FIG. 12 is a diagram showing the combination of FIGS. 12A and 12B. ” he corrected.

Claims

[Claims for Utility Model Registration] 1. A first catalytic converter installed on the upstream and downstream sides of a catalytic converter for purifying exhaust gas provided in the exhaust system of an internal combustion engine to detect the concentration of a specific component in the exhaust gas. , a second air-fuel ratio sensor; an air-fuel ratio adjusting means for adjusting the air-fuel ratio of the engine according to the output of at least one of the first and second air-fuel ratio sensors; and an output of the first air-fuel ratio sensor. a catalyst deterioration determining means for determining catalyst deterioration of the catalytic converter by comparison with an output of the second air-fuel ratio sensor; a catalyst deterioration display means for displaying the catalyst deterioration when the catalyst deterioration is determined; and catalyst recovery means for restoring the catalyst of the catalytic converter when the catalyst deterioration is determined and the switch means is turned on. 2. The catalyst deterioration determining means includes engine temperature determining means for determining whether the cooling water temperature of the engine is equal to or higher than a predetermined value, and each time the cooling water temperature of the engine changes from less than the predetermined value to above the predetermined value. Deterioration of the catalyst in the catalytic converter is determined, and further, only when the deterioration of the catalyst in the catalytic converter is determined twice consecutively, deterioration of the catalyst in the catalytic converter is considered to be determined. An air-fuel ratio control device for an internal combustion engine according to scope 1. 3. The catalyst deterioration determination means determines the reversal frequency (of the output of the first air-fuel ratio sensor)
means for calculating a ratio between the reversal frequency (or period) and the reversal frequency (or period) of the second air-fuel ratio sensor; and a determining means for determining whether the ratio of the calculated frequency (or period) is less than or equal to a predetermined value. The air-fuel ratio of an internal combustion engine according to claim 1, wherein the catalyst deterioration of the catalytic converter is determined when the frequency (or period) ratio is equal to or less than the predetermined value. Control device. 4. The air-fuel ratio control device for an internal combustion engine according to claim 1, wherein the catalyst recovery means includes means for enriching the air-fuel ratio of the engine for a predetermined period of time.