JPS593125A - Fuel supply control device - Google Patents

Abstract

PURPOSE:To have complicated control of the amount of fuel supply with high accuracy and simple and uncostly configuration by coupling a control rack to control the amount of fuel supply with an air actuator and by controlling air supply thereto using an electronic controller. CONSTITUTION:Information from sensors 16-20 mounted at the accelerator pedal 15 and engine 1 is fed into a micro-computer 14. If this micro-computer 14 opens, for ex., a solenoid-operated valve 10, air in an air tank 12 is fed into an air actuator 9 through a pipe 13, and the pneumatic pressure moves the control rack 8 to the left with the aid of a diaphragm and rod to increase the amount of fuel supply during one cycle of operation of each pump unit 6 of the fuel injection pump 2. If the micro-computer 14 opens another solenoid-operated valve 11, on the other hand, the air actuator 9 is put in communication with the outside through air exhaust hole, so that the control rack 8 now moves to the right to decrease the amount of fuel supplied.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling the amount of fuel supplied, and more particularly to a device that controls the amount of fuel supplied by moving a control rack provided on a fuel injection pump. .

A diesel engine is equipped with a fuel injection pump, which sequentially supplies fuel to each cylinder of the engine. The amount of fuel supplied by this pump is controlled by a control rack. That is, when the control rack moves, the barrels of each pump unit of the fuel injection pump rotate, thereby changing the effective stroke of the granger.

The control rack is controlled by the accelerator pedal via the load lever and mechanical governor.

Controlling the control rack of a fuel injection pump using such a mechanical governor has the disadvantage that it is complicated and cannot perform highly accurate control. Mechanical governors also have the disadvantage that their structure is extremely complex and adjustment is difficult. Furthermore, it is heavy and is very disadvantageous in terms of cost.

The present invention has been made in view of these problems, and is capable of performing complex control of the amount of fuel supplied with high precision, and has a simple structure and is advantageous in terms of cost. The purpose of this invention is to provide a control device for the following.

The present invention will be explained below with reference to illustrated embodiments.

FIG. 1 shows a diesel engine 1 according to this embodiment, and a fuel injection pump 2 is provided on the side of the engine 1. As shown in FIG. The fuel injection pump 2 is driven by the engine 1 via a gear 3, a timer 4, and a camshaft 5. That is, each pump unit 6 of the fuel injection pump 2 has a camshaft 5.
It is designed to be driven by a cam fixed to the.

Each pump unit 6 and the cylinder of the engine 1 are connected by a fuel supply pipe 7, and fuel is sequentially supplied from the fuel injection pump 2 into each cylinder through the viagua.

The fuel injection pump 2 is equipped with a control rack 8, and this control rack 8
It is designed to be driven by an air actuator 9 attached to the end of the.

The air actuator 9 includes a pair of electromagnetic valves to and tt, and air is supplied and discharged by these electromagnetic valves to and tt. The solenoid valve lO is connected to the air tank 12 via an air supply pipe 13. Further, the solenoid valves to and tt are each operated by control signals from the microcomputer 14.

The accelerator pedal 1 is connected to this microcomputer 14.
5, a sensor 16 that detects the amount of depression of the pedal 15, a rotation detection sensor 17 that detects the engine rotation speed, a water temperature detection sensor 18 that detects the temperature of the engine cooling water, and an engine oil temperature detection sensor. 19. The detection output of the position detection sensor 20 that detects the position of the control rack is inputted. Furthermore, although not shown here, information regarding the gear ratio of the transmission, the traveling speed of the vehicle, the state of the clutch, the presence or absence of brake operation, etc. is also input to the microcomputer 14.

Next, the structure of the air actuator 9 will be explained with reference to FIG. 2. The air actuator 9 consists of a cylindrical casing, and a trap diaphragm 21 is attached to divide the inside of the casing into two.

A rod 22 is fixed to this diaphragm 211C, and this rod 22 is connected to the control rack 8 via a pin 23. Also diaphragm 20
A compression coil spring 24 is interposed on the left side in FIG. 2, and the diaphragm 21 is pushed to the right by this spring 24.

And in the room on the right side of this diaphragm 21 is a solenoid valve t.
o, tt are installed. That is, the solenoid valve lO is attached to the air supply hole 25, and the solenoid valve 11 is attached to the air discharge hole 26. Further, a detected element 28 is attached to the control rack 8 via an arm 27, and this detected element 28 is inserted into the position detection sensor 20, so that the position of the rack 8 is detected by this trap. It has become. Note that the position detection sensor 20
may consist, for example, of a working transformer.

In the above configuration, the microcomputer 14
Various types of information are supplied to the sensor 16, 17, 18, 19, 20, etc. Based on such information, for example, when the microcomputer 14 supplies a control signal to the solenoid valve 10, the solenoid valve 10 is opened, and therefore air is supplied from the air tank 12 through the air supply pipe 13 and the air supply hole 25. Compressed air is supplied into the actuator 9.

Then, the diaphragm 21 moves to the left in FIG. 2 against the compression coil spring 24 due to air pressure, and the rod 22 fixed to the diaphragm 21 also moves in the same direction. Accordingly, the control rack 8 connected to the rod 22 also moves to the left, thereby increasing the amount of fuel supplied by each pump unit 6 of the fuel injection pump 2 at one time.

Next, when the microcomputer 14 supplies a control signal to the solenoid valve 11, the solenoid valve 11 is opened by this signal, and therefore the air actuator 9 is communicated with the outside through the air exhaust hole 26. Therefore, the air in the chamber on the right side of the diaphragm 21 of the air actuator 9 is exhausted to the outside through the air exhaust hole 26, and the diaphragm 21 is pushed to the right by the compression coil spring 24. Therefore, in this case, rod 2
2 and the control rack 8 move to the right in FIG. 2, and the amount of fuel supplied by the fuel injection pump 2 decreases.

As described above, according to the fuel supply amount control device of this embodiment, various information regarding the engine 1 or the vehicle is manually inputted to the microcomputer 14, and the microcomputer 14 transmits control signals electromagnetically and in response to the information. By supplying fuel to the valves 10 and tl, complex control of the fuel injection pump 2 can be performed with high precision. Therefore, it becomes possible to accurately control the amount of fuel supplied by the fuel injection pump 2. Also, in this control device,
Since the control rack 8 is directly connected to the rod 22 of the air actuator 9 for movement,
The structure is very simple and the weight is m < i-).
Furthermore, it is possible to provide a fuel supply amount control device that is very economical in terms of cost. Also, diaphragm 21
Because it uses an air actuator equipped with
It eliminates air leaks and allows highly accurate control.

As described above, the present invention connects a control rack to an air actuator, and controls the supply of air to the air actuator by a control signal from an electronic control device, so it does not require the conventional method. It is possible to omit a mechanical governor, which has a complicated structure, is heavy, and is extremely disadvantageous in terms of cost. Furthermore, since the supply of air to the air actuator is controlled by an electronic control device, it is possible to perform complex control with high precision. Further, since the structure is simple, the increase in weight is small, and it is possible to provide a fuel supply amount control device that is very advantageous in terms of cost.

[Brief explanation of drawings]

FIG. 1 is a side view of a main part showing a control device for a fuel injection pump of a diesel engine according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a main part of a control mechanism of a control rack of this fuel injection pump. . In addition, in the symbols used in the drawings, 1 2... Fuel injection pump, 8... Control rack, 9... Air actuator, to, tt... Solenoid valve, ! 4...Microcomputer. Applicant Hino Motors Co., Ltd.

Claims (1)

[Claims] In a device that controls the amount of fuel supplied by moving a control rack provided on a fuel injection pump, the control rack is connected to an air actuator, and air is supplied to the air actuator from an electronic control device. 1. A fuel supply amount control device, characterized in that the fuel supply amount is controlled by a control signal.