JPS61215450A - Time controller of electromagnetically operable fuel jet valve - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is capable of electromagnetic actuation as defined in the preamble of claim 1 -r! This invention relates to a control device that performs time control of a certain fuel injection valve.

Such a device is used in particular for metering fuel into the intake system of an engine.

PRIOR ART Such known devices use means for forming current pulses, for example monostable multivibrators. However, the A pulse length of this current pulse depends on a controlled variable, for example on the amount of air drawn in. The current, e Lus, whose pulse length or duration is determined by the monostable multivibrator, is amplified by the P-Leiper amplifier to provide the required output, thereby controlling the electromagnetic coil or excitation coil of the fuel injector. Excite. As a result, the needle valve element leaves the valve seat and fuel is injected into the intake system for a time corresponding to the length of the pulse or the duration of the e-pulse.

In detail, the fuel injection valve belonging to the prior art consists of a nozzle portion having an electromagnetic winding and a soft iron core arranged in a casing of the valve, and the electromagnetic winding and the soft iron core form an electromagnetic coil. This electromagnetic coil cooperates with a mover arranged opposite to it. This armature is connected to a needle valve which is guided in the nozzle part (Federal Republic of Germany Patent No. 2,349,584).

Problem to be Solved by the Invention In order to meter a desired amount of fuel into an intake system, for example into the intake pipe of an engine, it is necessary to There is a problem in that it is necessary to allocate a corresponding injection amount to the electricity and pels that are frequently generated by electronic devices. For this purpose, it is necessary to precisely adjust the fuel injection valve. This adjustment is usually very time-consuming, because after measuring the fuel injector, it is often disassembled, readjusted, and measured repeatedly to ensure that the fuel injector remains in control for a long time. t' because it must be metered to the desired injection quantity that corresponds to the time or pulse length. Until now, it was thought that this problem could be solved by the manufacture of suitable fuel injection valves. For example, the position of the armature relative to the needle may vary, so that in particular the stroke of the needle must be adjusted, which results in relatively high manufacturing costs. It is known that a special connecting body is provided between the mover and the needle valve body in order to keep the error in the stroke of the needle valve body within an allowable range. The end force of the needle valve body accommodated in the needle valve body has a ring-like f-shaped foot and a ring Akita formed by a processed ring groove, and the end of the needle valve body and the mover are press-joined. This press joining involves pressing and press-fitting the wall of the hole in the mover that accommodates the end of the needle valve body into the face of the ring Akita and the ring groove located between these ring Akitas. (Patent Specification No. 2349584). However, this special solution 1 does not account for all the influences that control the metering of the injection quantity on the control time of the electromagnetically actuated fuel injection valve.

The object of the invention is to provide a time-controlled control device for an electromagnetically actuated fuel injection valve and, in particular, the fuel injection valve itself, such that the desired injection quantity can be metered within narrow tolerances by means of the fuel injection valve! The goal is to be able to do so.

Means for Solving the Problem The above object is achieved by a time-controlled control device for a fuel injection valve, which has the features described in the characterizing part of claim 1.

The principle of the invention is to forego narrow tolerance mechanical adjustments and instead detect them by reading them from the so-called characteristics of each fuel injector, which are manufactured and, if necessary, coarsely mechanically adjusted. The principle is to modify and take into account the characteristics when creating the current flow that excites the fuel injector in the injection electronic device. The pulse duration or length of this current pulse is therefore not, as usual, determined only by one control value, in particular the amount of air sucked into the internal combustion engine, but by the fuel injection metering the fuel. It also depends on the characteristics of the valve.

The characteristic in this case is the ratio of the injection quantity to the control time of the fuel injector, the control time being equal to the pulse duration of the exciting current pulse.

This property is uniquely and reliably imparted to the fuel injection valve by determining the dimensions of the electrical elements installed outside or inside the fuel injection valve.

The electric element that provides the characteristic consists of one electrical resistance), and its resistance value can be used as a measurement value of the characteristic (the amount of ejection corresponding to the control time).

It is convenient to place the electrical resistance inside the insulating part of the fuel injection valve! A plug-in piece is then provided in the insulating part, via which the fuel injector is normally connected to the engine electronics. For connecting the electrical resistance, it is advantageous to use a further plug-in piece, which is electrically connected to the resistance. In this case, it is possible to connect the resistor to one of a plurality of plugs, which plugs are usually used for supplying current pulses to electromagnetic coils.

The lever element is then electrically connected to two plugs located in the insulating part.

Electrical manipulation of the dimensions of the electrical element to provide the properties is described in claim 5. As a result, the duration or length of the current pulse for exciting the electromagnetic coil of the fuel injector remains limited to only one control value, in particular only the intake air quantity. It is not determined by, but also depends on the components that provide the characteristics. An advantageous means for realizing this according to claim 5 is to connect the electrical element to means for generating the current pulses via an analog-to-digital converter and a table storage, preferably a ROM. In this case, it is possible to design the R pulse generating means in such a way that the length of the current pulse is controlled by the characteristic values of the electric element. In particular, the length of the current pulse is determined not only by the control variable, ie the air volume, which controls the monostable multivibrator in the usual way, but also by controlling this monostable multivibrator by a modified value. do. Note that this correction value is determined from the table storage according to the electrical value read from the electrical element.

However, the duration of the current/e pulse is formed by making it depend only on the control value, which is the amount of air supplied to the monostable multivibrator, as usual, but the duration of the current/e pulse is The duration is changed in the subsequent stage connected to the monostable multi-9ibrator by means of coefficients which are likewise taken from the table storage in dependence on the characteristics of the electrical elements (
You can also multiply by 1. .

Each fuel injector used in an injection device has its own unique
An electric element having the characteristics of the corresponding fuel injection valve is fixedly assigned, and the characteristic value of this electric element is read out separately and the pulse duration of the current pulse supplied to the corresponding fuel injection valve is modified. 1, the device with fuel injection valves can be supplied separately for the so-called multi-point injection valves, Φ, 6 or 8, compared to the conventional mechanically regulated nozzles. This allows the nozzles to operate much better synchronously. Therefore fuel is saved1
This reduces harmful substances emitted with exhaust gas.

Example Next, embodiments of the present invention will be described in detail using the drawings.

In reality, when an internal combustion engine is used in an automobile, there is not one but a plurality of fuel injection valves, and the resistances of these injection valves are sequentially read out in order to control the amount to be metered by each fuel injection valve.

In FIG. 1, l denotes a valve casing, and an electromagnetic coil 3 is accommodated in a through hole 2 of this casing.

The electromagnetic coil is located opposite the movable coil. The mover is pushed away from the υ electromagnetic coil by the closing spring 5 when the electromagnetic coil is not energized, and is attracted toward the electromagnetic coil when the electromagnetic coil is energized.

A needle valve body 6 is connected to this mover. The needle valve body is pressed against the valve seat 7 by the action of the closing spring 5, and in this state closes the fuel injection valve.

Fuel supply is provided by a fuel supply boat 8, a longitudinal through hole 9, and a vertical groove 1.
It passes through different spaces including 0 and 11 into the annulus 12 upstream of the valve seat.

In order to excite the electromagnetic coil 3, this coil is connected through conductors (not shown) to two plugs, which are mounted in the insulating part 13. In the figure, only one insert piece 14 is visible; the other two insert pieces are not shown.

A resistor 16 is embedded in the notch 15, and the resistance value of the resistor is proportional to the injection amount corresponding to the characteristics of the fuel injection valve, that is, the control time. Similarly, the resistance glue-P wire 17 connects to the insertion valve 1.
4, and the second terminal of the resistor is connected to one of the plug-in pieces (not shown).

FIG. 2 shows a control device for time-controlled operation of the fuel injection valve of FIG. The injection electronics system shown in FIG. 2 is typically part of a total injection electronic system that controls multiple fuel injectors of the type shown in FIG. .

The main part of the injection electronics is a monostable multivibrator 1
8'e, it is possible to vary the instability time of this monostable multivibrator proportionally to the voltage signal at the input 19. In the engine electronics, a voltage signal is generated by an air quantity sensor 20, which detects the quantity of air taken in by the internal combustion engine.

A pulse is thus generated at the output 21 of the monostable multivibrator, the JR pulse duration or pulse length of which is dependent on the air volume detected by the air volume sensor 20. The pulse is amplified by a P-Leiper amplifier 22 and fed through the plug-in piece 23 to the electromagnetic coil 3, which is energized for the duration of the pulse.

The fuel injection valve to which the electromagnetic coil 3 belongs thus meters and supplies the intake device with a fuel quantity proportional to the pulse duration. The amount depends on the characteristics of the fuel injector, ie the ratio of injection amount to control time, which is determined by construction and manufacturing.

This characteristic, or the deviation of the characteristic from the target value, is determined by the resistance 16
The resistance value of this resistor is adjusted or selected in response to the characteristic or deviation from the characteristic. This resistor with a given resistance value is a component of the fuel injection valve of FIG.

The resistance value read by the resistor is inputted into a table stored in the ROM 25 as an address via the analog-to-digital converter 24. Addresses in the table are assigned modification amounts. The respective correction value corresponding to the resistance value of the resistor 16 is read from a table in the ROM 25 and is input to the second input 26 of the monostable multivibrator. According to the internal structure of the monostable multipisolator, the pulse duration or pulse length, which is initially determined by the control value in accordance with the air amount, is corrected in accordance with the correction amount from the table in the ROM 25. is possible. In that way, the monostable multi/ζibrator delivers pulses with a pulse duration that is sufficiently large, so that the fuel quantity metered by the fuel injector is controlled by the fuel injector at a controlled time. It is equal to the exact fuel amount when indicating the target value of the corresponding characteristic, that is, the target injection value. This means that the duration of the pulses produced by the monostable multivibrator 18 without correction quantities is lengthened or shortened to such an extent that it is commensurate with the deviation between the characteristics of the associated fuel injector and the desired value of the characteristics. There is a thing called f.

As mentioned above, by extending the injection electronics shown in FIG. 2 to modified control of multiple fuel injectors, very good Possible to achieve synchronous operation-1! be. The cost of the electronic part of the device for detecting the resistance assigned to the fuel injection valve is low, since the injection electronics usually includes a microprocessor with an analog input for connecting the resistance. Because the system is set up
46ru.

Effects of the Invention According to the present invention, the length of the electric current and pulse for controlling an electromagnetically actuable fuel injection valve does not depend only on the amount of intake air as in known devices, but depends on the characteristic quantity of the attached electric element. By making corrections, it is possible to accurately determine the injection amount, and in devices with multi-point injection valves, it is possible to guarantee synchronized operation from multiple nozzles. Additionally, fuel can be saved and harmful components of exhaust gas can be reduced.

[Brief explanation of the drawing]

Figure ta1 is an enlarged cross-sectional view of this fuel injector, in which a resistor having the characteristics of a fuel injector is arranged, and Figure 2 is an injection electronic device belonging to this device, which has an electromagnetic coil and an electric resistance of the fuel injector. FIG. DESCRIPTION OF SYMBOLS 1... Valve casing, 2... Through hole, 3... Electromagnetic coil, Φ... Mover, δ... Closing spring, 6...
... Needle valve body, 7... Valve seat, 8... Fuel supply port,
9...Longitudinal through hole, 10.11...Vertical groove, 12
... Annular part, 13 ... Insulating part, 14 ... Insert piece, 15 ... Notch, 16 ... Resistor, 17 ... Lee h% conductor wire, 18 ... Monostable multi-piece mibrator,
19...Input side, 2゜...Air amount sensor, 21...
・Output side, 22...Driver amplifier, 23...Plug-in piece, 24...Analog-digital converter, 25...
・ROM0 18... Monostable multi/stable ibrator 19... Input side 20... Air amount sensor 21... Output side 'FIG, 2

Claims (6)

[Claims] 1. In a time-controlled control device for electromagnetically actuated fuel injection valves of an internal combustion engine with injection electronics, each fuel injection valve (1-14) is provided with one electrical element (16), The electric element has a characteristic quantity (
An electromagnetically actuable fuel injection valve characterized in that the dimension is determined in proportion to the injection amount (injection amount relative to the control time) and is connectable to an injection electronic device (18, 22) for controlling the injection time. time-controlled control device. 2. Claim 1, wherein the electric element is a resistor (16)
Apparatus described in section. 3. The fuel injection valve comprises an insulating part with a plug mounted in the insulating part for connecting the electromagnetic coil to the injection electronics, the electrical element (resistor 16) being connected to the insulating part (13). Claim 1 arranged in and connected to two plug-in pieces (e.g. 14)
2. The device according to item 2 or item 2. 4. Claim in which one of the two plug-in pieces (14), which are in contact with the electrical element (resistor 16), is provided for connecting the electromagnetic coil (3) to the engine electronics (18, 22). The device according to item 3 within the range of 5. It contains means (monostable multivibrator) for forming a current pulse whose length depends on one control variable (air volume), and each electric element ( The resistor 16) is connected via an analog-to-digital converter (24) and a table storage (ROM 25) to means for controlling the length of the current pulse (monostable multivibrator 18). The device according to any one of the ranges 1 to 4. 6. There is an electric resistance (16
2. The device as claimed in claim 1, further comprising an insulating part for an internal combustion engine and a plug installed in the insulating part.