JPH0475387B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a fuel increasing device for a carburetor mainly applied to an automobile engine.

(b) Prior art As a prior art for this type of fuel increase device, there is a previously filed Japanese Patent Application No. 129217/1983 (Patent Application No. 57617/1983)
As shown in No. 1), it has an electromagnetic actuator that reciprocates using a spring force and an electromagnetic force that is generated only when a pulse voltage is applied, and this actuator causes a piston to reciprocate to correspond to the displacement volume of the piston. A fuel injection pump is provided to sequentially supply the amount of fuel to the carburetor in a vaporized manner, and a pulse voltage is applied to the actuator during acceleration, and the number of times or time of application is controlled. Some fuel injection pumps are designed to function as an acceleration pump.

Recently, attempts have also been made to extend the range in which the actuator is operated to include the time of engine startup, thereby abolishing the conventional choke mechanism.

However, when trying to make a single fuel injection pump function as a substitute for the chi-yoke mechanism and as an acceleration pump, the discharge to the fuel injection pump changes depending on whether the engine cooling water temperature is low or high. The quantity requirement characteristics will be quite different. In other words, the operating conditions in the region where the engine cooling water temperature is low include when starting the engine, cranking, warming up, or driving at low temperatures. It is preferable to supply a large amount of fuel, and also in the case of the other embodiments described above, it is desirable to supply a large amount of fuel. On the other hand, in the region where the engine cooling water temperature is high, that is, in the operating region after warm-up,
There is no need to significantly increase the amount of fuel as there is at low temperatures; rather, improving fuel economy is a more important issue. Therefore, in such a region, it is desirable to increase the necessary minimum amount of fuel as precisely as possible during acceleration. However, conventional fuel injection pumps are operated so that the amount of fuel discharged per one reciprocating movement of the piston is always constant. Therefore, if the fuel discharge amount is set in accordance with required characteristics such as during startup, the resolution of the pump decreases, making it difficult to accurately increase the amount of fuel at high temperatures.

(C) Purpose The present invention was made with attention to the above-mentioned circumstances, and it is possible to quickly increase a large amount of fuel in a region where the engine cooling water temperature is low, and to increase the amount of fuel quickly in a region where the engine cooling water temperature is high. , provides a fuel increase device for a carburetor that is capable of increasing the amount of fuel with high resolution and precision, and allows a single fuel injection pump to properly perform the functions of a chi-yoke mechanism and an acceleration pump. The purpose is to

(D) Structure In order to achieve the above object, the present invention includes an electromagnetic actuator 30 that reciprocates by a spring force and an electromagnetic force generated only when a pulse voltage is applied. is reciprocated to sequentially supply the amount of fuel corresponding to the displacement volume of the piston 27 to the carburetor 1 until the amount of fuel discharged per unit time reaches a predetermined value of the frequency or voltage value of the pulse voltage. A fuel injection pump 23 is provided which has a characteristic B in which the fuel injection pump increases as the frequency or voltage value increases in the region, and decreases as the frequency or voltage value increases in the region exceeding the predetermined value. and a fuel increasing device configured to apply a pulse voltage to the actuator 30 during acceleration and to control the number of times or duration of the application to cause the fuel injection pump 23 to function as a choke mechanism and an acceleration pump. , is electrically connected to the water temperature detection means 4 for detecting the engine cooling water temperature and the actuator 30, and utilizes only the region exceeding the predetermined value in the fuel discharge amount characteristic B per unit time of the fuel injection pump 23. control means 5 which controls the frequency or voltage value of the pulse voltage to be lower when the water temperature detected by the water temperature detection means 4 is low, and controls the frequency or voltage value to be higher when the water temperature is high; It is characterized by having the following.

(e) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a system explanatory diagram of a fuel increasing device according to the present invention, in which 1 is a carburetor of an automobile engine, 1a is a throttle valve of this carburetor 1, and 1
b is a float chamber, 2 is a load detection means for detecting the magnitude of the load on the engine, 3 is a rotation detection means for detecting the rotational speed of the engine, 4 is a water temperature detection means for detecting the engine cooling water temperature, and 5 is each of these. A control means for processing signals outputted from the detection means 2, 3, and 4, and 6 are fuel injection means for supplying starting fuel or acceleration fuel to the carburetor 1 under the control of the control means 5.

The load detection means 2 includes an idle switch 7 that outputs an idle signal P1 when the engine is in an idling state in relation to the throttle opening;
The first controller outputs a light load signal P2 when the intake pipe negative pressure shows a value closer to the atmosphere than -450 mmHg, for example.
vacuum switch 8, and a second vacuum switch 9 that outputs a medium load signal P3 when the intake pipe negative pressure is closer to the atmosphere than -300 mmHg, for example.
and a third vacuum switch 10 that outputs a high load signal P4 when the intake pipe negative pressure exhibits a value closer to the atmosphere than -150 mmHg, for example.

The control means 5 is constituted by an ordinary microcomputer system comprising a central processing unit 12, a memory 13, and interfaces 14 and 15. Temperature detection means 4
Information regarding the temperature of the cooling water and the rotational speed of the engine, which are respectively detected by the rotation detecting means 3 attached to the rotational system of the engine, is input. The rotation detection means 3 may be any device that can detect the rotational state of the engine, such as a rotation sensor installed on a mechanical rotating part, a boost sensor, or a combination of a boost sensor and a throttle opening sensor. Something like this is fine.
The control means 5 thereby senses the temperature of the cooling water and the engine rotation speed, and compares and calculates the engine rotation speed with the determined rotation speed stored in the memory 13 to determine the engine rotation speed. Make specific decisions. In other words, for example, when the rotation speed is less than 50 rpm, it is before the engine starts and when the rotation speed is between 50 and 500 rpm.
When it is m, it is cranking and the rotation speed is
When the engine speed exceeds 500 rpm, it is determined that the engine is in a state where the engine has already completed a complete combustion. Based on this determination of the engine rotation speed, injection command signals 01 to 04, which will be described later, are output.

On the other hand, the memory 13 of the control means 5 stores in advance a fuel supply pattern to be supplied to the carburetor 1 for each rotational state of the engine in relation to the temperature of the engine cooling water. Therefore, the central processing unit 12 of the control means 5 senses the rotational speed of the engine, determines its rotational state, and adjusts the fuel discharge amount to an appropriate amount stored in the memory 13 for this determined rotational state. Based on this, the program is programmed to issue various fuel supply commands to the fuel injection means 6 via the interface 15. Further, the interface 1 of this control means 5
4 includes each switch 7 of the load detection means 2,
Signals P1, P2, P3, P4 from 8, 9, 10
is now also entered. The control means 5 reads each of the signals P1, P2, P3, and P4 input to the interface 14 at fixed time intervals and stores them in the memory 13, and also stores the stored signals each time (nth time). P1, P
2, P3, P4 next (n+1th) signal P
1, P2, P3, and P4 to determine the degree of acceleration, and a type of injection command signal according to the determination result, for example, a small amount injection command signal A1, a medium amount injection command signal A2, or a large amount injection command signal. It is programmed so that it can be sequentially output via any interface 15 of A3.

Next, the fuel injection means 6 connects an inlet 17 having a check valve 16 to the float chamber 3 via an inlet passage 18, and connects an outlet 19 to the check valve 2.
1, an electromagnetic fuel injection pump 23 opened into the intake passage 1c of the carburetor 1 through an outlet passage 22 having an injection command signal 01, 02, 03, 04 or A
1, A2, and A3, and the fuel injection pump 23 is activated a number of times or for a time corresponding to each of these signals.
and a driver 24 for driving. The fuel injection pump 23 houses a piston 27 in a cylinder 26 that forms a pump chamber 25, and an electromagnetic actuator 30 that operates the piston 27 in cooperation with a spring 28 and a solenoid 29.
It is constructed so that it can be moved forward and backward to operate the pump mechanism.

Further, the driver 24 is connected to the actuator 3.
The piston 27 is moved forward and backward by applying a pulse voltage to the solenoid 29 of No. 0, and the number of times or application time of the pulse voltage is determined by the injection command signal 01, 02, 03, 04 or A1,
By changing it in accordance with A2, A3, etc., the fuel increase value by the fuel injection pump 23 can be adjusted according to the program. That is, injection command signals 01, 02, 0
3, 04 or A1, A2, A3 are signals that define the application timing and application duration of a pulse voltage applied to the actuator 30 in response to a pump drive signal Q, which will be described later. Here, injection command signal 01 is applied before engine startup, injection command signal 02 is applied during cranking, injection command signal 03 is applied after engine startup complete combustion, and injection command signal 04 is applied during cranking and after output of injection command signal 02. These are the signals that are output when the top occurs.

In such a fuel increase device, the program of the control device 5 is expanded to change the frequency of the pulse voltage supplied to the fuel injection pump 23 in accordance with the temperature of the engine cooling water detected by the water temperature detection means 4. That's what I do. Specifically, the electromagnetic actuator is configured to reciprocate the piston 27 using the spring force of the spring 28 and the electromagnetic force generated only when a pulse voltage is applied to the solenoid 29. 30, and the actuator 30 causes the piston 27 to reciprocate to sequentially supply fuel in an amount corresponding to the displacement volume of the piston 27 to the carburetor 1.

The fuel injection pump 23 has a characteristic that the amount of fuel discharged per stroke gradually decreases as the frequency of the pulse voltage applied to the actuator 30 increases, as shown by the solid line A in FIG. There is. This characteristic is that as the frequency increases, the time during which the solenoid 29 pulls the piston 27 against the elastic force of the spring 28 becomes shorter in one cycle, and one stroke becomes shorter as the frequency increases. This is due to being shorter. In other words, as the initial frequency is shifted from a low value to a high value, the fuel discharge amount per unit time gradually increases as shown by the broken line B in FIG. It has a characteristic of having a parabolic curve, with the highest value in the vicinity). That is, the amount of fuel discharged per unit time increases as the frequency increases until it reaches a predetermined value, and conversely decreases as the frequency increases in a region that exceeds the predetermined value. This is because as the frequency increases, the amount of fuel discharged per cycle decreases due to the responsiveness of the mechanical parts, but the number of reciprocations of the piston 27 within a unit time, that is, the number of strokes increases. In other words,
In the region up to the predetermined value, the amount of fuel discharged per cycle gradually decreases, but as the number of strokes per unit time increases, the amount of fuel discharged per unit time increases. In a region where the frequency increases beyond a predetermined value, the amount of fuel discharged per cycle becomes even smaller, so even if the number of strokes increases as the frequency increases, the amount of fuel discharged per unit time does not increase. In addition to this,
As the frequency increases, the movement of the piston 27 in that case becomes faster, but conditions such as the inability of the fuel to follow the movement of the piston 27 due to viscosity etc. are compounded, and as a result, the amount of fuel discharged per unit time decreases. It is something that decreases. These characteristics are achieved by the electromagnetic actuator 30 that operates in cooperation with the spring 28 and solenoid 29.
Basically, a fuel injection pump having a structure in which a piston 27 is moved forward and backward is provided.

This example utilizes such characteristics,
As shown by broken line C in FIG. 3, when the engine cooling water temperature is low, the frequency of the pulse voltage is controlled to a lower range than the predetermined value, and when the water temperature is high, the frequency is controlled to a higher range. The solid line D in Fig. 3 is drawn between the engine cooling water temperature and the fuel discharge amount per cycle of the fuel injection pump.
I am trying to create a relationship as shown below. FIG. 4 shows the control means 5 for performing such control.
FIG. 2 is a flowchart showing an overview of a program built into the computer. That is, first, when the ignition key is turned on, water temperature information from the water temperature detection means 4 is read. Then, a driving frequency corresponding to the water temperature is calculated by processing using a mathematical formula stored in advance in the memory 13, and a pump driving signal Q corresponding to the calculated frequency is outputted to the driver 24. This work is then repeated at regular intervals. In this case, before and after starting, as described above, the memory 13 of the control means 5 stores the fuel supply pattern to be supplied to the carburetor 1 for each rotational state of the engine in relation to the temperature of the engine cooling water. is stored in advance, so the pump is driven at the timing of any of the injection command signals 01 to 04 determined by the detected engine rotation speed so that the appropriate fuel discharge amount calculated from the coolant temperature is obtained. The fuel injection pump 23 is driven by a drive signal corresponding to the signal Q. In addition, during acceleration when the engine load condition changes, the pump drive signal Q corresponding to the drive frequency according to the water temperature is
The fuel injection pump 23 is driven by the combination of and the injection command signals A1 to A3.

With such a configuration, it is possible to increase the amount of fuel from the fuel injection pump 23 to the carburetor 1 in a predetermined pattern at the time of startup and acceleration, so it is possible to increase the amount of fuel from the fuel injection pump 23 to the carburetor 1 in a predetermined pattern at the time of startup and acceleration. Pumps can be abolished. Moreover,
When the engine water temperature is low, the frequency of the pulse voltage applied to the fuel injection pump 23 is lowered and the amount of fuel output per cycle of the pump 23 is increased, but when the engine water temperature is high, As the frequency increases, the amount of fuel discharged per cycle decreases. Therefore, before starting, it is possible to supply the necessary fuel for yoking in a short time,
Additionally, it is easy to quickly replenish a relatively large amount of fuel when the engine is cold. Furthermore, after the engine warms up, the resolution of the fuel injection pump 23 improves, making it possible to accurately supply the minimum amount of fuel required during acceleration, without degrading the acceleration performance of the engine. can improve fuel economy.

In addition, in a fuel injection pump in which the piston is reciprocated by an electromagnetic actuator that reciprocates by a spring force and an electromagnetic force that is generated only when a pulse voltage is applied, the solid line in Fig. 5 is used.
As shown in A', it also has the characteristic that by increasing the voltage value of the pulse voltage applied to the actuator (keeping the frequency constant), the amount of fuel discharged per cycle gradually decreases. Due to this characteristic, the amount of fuel discharged per unit time gradually increases as the pulse voltage increases, reaching its maximum value at a predetermined voltage (for example, around 8V), and when the voltage increases beyond the predetermined voltage. , which decreases as the voltage increases, resulting in a parabolic curve similar to that shown by the broken line B in FIG. Therefore, instead of changing the frequency of the pulse voltage, by changing the voltage as shown by the broken line C in FIG. 3, the ejection characteristics shown by the solid line D in FIG. 3 can be obtained. It's okay.

(F) Effect Since the present invention has the above-described configuration, it is possible to quickly increase a large amount of fuel in a region where the engine cooling water temperature is low, and at the same time, the resolution is high in a region where the engine cooling water temperature is high. It is possible to provide a fuel increasing device for a carburetor that is capable of increasing the amount of fuel with high precision and that allows a single fuel injection pump to properly perform the functions of a chiyoke mechanism and an acceleration pump without difficulty. .

[Brief explanation of the drawing]

Figures 1 to 4 show an embodiment of the present invention, where Figure 1 is a system explanatory diagram, Figure 2 is a characteristic diagram of the fuel injection pump, Figure 3 is a diagram showing control setting conditions, and Figure 4 is a diagram showing the control setting conditions. The figure is a flowchart showing the control procedure. FIG. 5 is a characteristic diagram of a fuel injection pump for explaining another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Carburizer, 4... Water temperature detection means, 5... Control means, 23... Fuel injection pump, 30... Actuator.

Claims (1)

[Claims] 1. An electromagnetic actuator 30 that reciprocates by a spring force and an electromagnetic force generated only when a pulse voltage is applied;
0, the piston 27 is reciprocated to sequentially supply fuel in an amount corresponding to the displacement volume of the piston 27 to the carburetor 1, and the amount of fuel discharged per unit time is a predetermined value of the frequency or voltage value of the pulse voltage. The fuel injection pump 23 is provided with a characteristic B in which the fuel injection pump increases as the frequency or voltage value increases in the region up to , and decreases as the frequency or voltage value increases in the region exceeding the predetermined value. The fuel injection pump 23 is configured to apply a pulse voltage to the actuator 30 at the time of starting and accelerating the engine, and to control the number of times or duration of the application so that the fuel injection pump 23 can function as a chiyoke mechanism and an acceleration pump. In the fuel increase device, water temperature detection means 4 detects the engine cooling water temperature.
and electrically connected to the actuator 30,
Using only the region exceeding the predetermined value in the fuel discharge amount characteristic B per unit time of the fuel injection pump 23, the frequency or voltage value of the pulse voltage is determined when the water temperature detected by the water temperature detection means 4 is low. 1. A fuel increasing device for a carburetor, comprising: control means 5 for controlling the frequency or voltage value to a lower side and controlling the frequency or voltage value to a higher side when the water temperature is high.