JPS58158147U

JPS58158147U - Air fuel ratio control device

Info

Publication number: JPS58158147U
Application number: JP5567882U
Authority: JP
Inventors: 周平栗林
Original assignee: 日産自動車株式会社
Priority date: 1982-04-19
Filing date: 1982-04-19
Publication date: 1983-10-21

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図はソレノイドバルブ付気化器の一例を示す断面図
、第２図ａ、　　ｂはソレノイドバルブの動作説明図、
第３図は空燃比制御回路の従来例を示すブロック図、第
４図ａ　−ｄは従来の空燃比制御装置の閉ループ制御時
の動作波形図、第５図はソレノイドバルブ付気化器の駆
動パルス幅（ＯＮｄｕｔｙ）と制御空燃比の関係を示す
特性図、第６図は本考案の一実施例を示す要部回路図、
第７図はパルス幅平均値判定回路の入力電圧とパルス幅
平均値の関係を示す図、−第８図は本実施例の作用説明
図、第９図は第８図中の制御信号と空燃比変化の関係を
示す図表である。　　　１・・・・・・気化器、１１・・・・・・ソレノイドバ
ルブ、１７・・・・・・空燃比制御回路、１Ｂ・・・・
・・空燃比判定回路、１９・・・・・・ＰＩ（比例積分
）制御信号発生回路、２０・・・・・・三角波発振器、
２１・・・・・・パルス幅変換回Ｌ２２・・・・・・パ
ワーアンプ、２３・曲・０゜センサ、２４・・・・・・
パルス幅平均値判定回路、２５・・・・・・ＰＩ制御信
号発生回路中の積分回路、Ｃ・・曲積分回路のコンデン
サ、Ｒ３，Ｒ１・・・・・・積分回路の抵抗、Ｍ・・・
・・・積分定数を切換えるアナログスイッチ。第４図第５図Figure 1 is a sectional view showing an example of a carburetor with a solenoid valve, Figures 2a and b are illustrations of the operation of the solenoid valve,
Fig. 3 is a block diagram showing a conventional example of an air-fuel ratio control circuit, Fig. 4 a - d are operating waveform diagrams during closed loop control of a conventional air-fuel ratio control device, and Fig. 5 is a drive pulse of a carburetor with a solenoid valve. A characteristic diagram showing the relationship between width (ON duty) and control air-fuel ratio, FIG. 6 is a main circuit diagram showing an embodiment of the present invention,
7 is a diagram showing the relationship between the input voltage of the pulse width average value determination circuit and the pulse width average value, - FIG. 8 is a diagram explaining the operation of this embodiment, and FIG. It is a chart showing the relationship between fuel ratio changes. 1... Carburizer, 11... Solenoid valve, 17... Air-fuel ratio control circuit, 1B...
...Air-fuel ratio determination circuit, 19...PI (proportional integral) control signal generation circuit, 20...Triangular wave oscillator,
21... Pulse width conversion circuit L22... Power amplifier, 23. Song/0° sensor, 24...
Pulse width average value determination circuit, 25...Integrator circuit in PI control signal generation circuit, C...Capacitor of curved integrator circuit, R3, R1...Resistance of integrator circuit, M...・
...An analog switch that changes the integral constant. Figure 4 Figure 5

Claims

[Scope of utility model registration request]

A circuit that receives the signal from the 02 sensor and outputs an air-fuel ratio judgment signal, a circuit that generates a proportional-integral control signal corresponding to the air-fuel ratio judgment signal, and a circuit that converts the proportional-integral control signal into a pulse signal with a pulse width corresponding to its voltage value. It consists of an air-fuel ratio control circuit including a circuit for controlling the air-fuel ratio, and a carburetor having a solenoid valve for air-fuel ratio control driven by the above pulse signal, and the relationship between the pulse width of the solenoid valve drive pulse and the controlled air-fuel ratio has a non-linear characteristic. In the air-fuel ratio control device shown in FIG. The proportional-integral control signal generation circuit is configured to increase the control speed when the pulse width is in the region, and to slow the control speed when the average pulse width value is in the region where the air-fuel ratio change is relatively large relative to the pulse width change. 1. An air-fuel ratio control device comprising means for switching an integral constant.