Automobile cold knowledge: the accelerator pedal does not directly control the oil circuit, but the "valve"

Whether the gasoline accelerator pedal directly controls the "oil circuit" and "accelerator" is believed to have puzzled many automobile users. Let's see how the accelerator works.

Knowledge: The fuel injection quantity of the engine should be calculated according to the air-fuel ratio, and the ratio is 14.7: 1. It can be understood that 1 kg gasoline needs 14.7 kg air (20.94% oxygen) to burn. So how much air is taken in, and can the fuel injection amount be adjusted according to the air intake standard? The answer is obviously yes.

1: old cable throttle valve. The pedal of the cable accelerator is like a mechanical control valve. The action of stepping on and releasing the pedal is to control the opening of the throttle through a connecting rod or a cable. The deeper you step on the pedal, the greater the throttle opening. Throttle is the last valve in the engine intake system. The intake speed is controlled by the opening of the damper, and the intake volume can naturally be controlled by speed control.

This is the concept of cable throttle fuel injection system, but the cable structure may be faulty (damaged during driving), and the cable control will also change the opening due to metal fatigue. Uncontrollable intake accuracy determines the poor combustion adequacy of mixed oil and gas, so this technology has been eliminated.

Figure 1: Concept of air inlet of cable throttle valve

Figure 2: Cable Throttle Structure

2: New electronic throttle! Now mass-produced passenger cars all use electronic throttles. This pedal is no longer connected with the mechanical structure, and has completely evolved into an ordinary "resistance switch". The depth (stroke) of the pedal adjusts the resistance, and the change of the resistance will naturally affect the strength of the current.

To put it bluntly, the current transmitted to the control unit is controlled by pedaling, and then the motor is controlled by different intensity standards, and the opening of the flap door is controlled by the throttle of the motor. Complete electronic control is bound to have very high precision, so the air-fuel ratio can also reach the ideal standard, or the full combustion of mixed gas can reduce the formation of carbon deposits and the total emission.

Figure 1: electronic accelerator pedal structure

Figure 2: Structural characteristics of pedals

This article comes from car home, the author of the car manufacturer, and does not represent car home's position.