JPS6357617B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial Application Field The present invention relates to an accelerating fuel increasing device for a carburetor, which is mainly applied to automobile engines. (b) Prior art The carburetor installed in an automobile engine has
Generally, an acceleration fuel increase device is installed to prevent the air-fuel mixture from becoming temporarily lean when the throttle valve is suddenly opened, and to supply the rich air-fuel mixture necessary for acceleration. be. By the way, conventional acceleration fuel increasing devices include an acceleration pump configured to advance or retreat a piston or the like by a fixed stroke in accordance with the opening/closing operation of a throttle valve, and increase or decrease the volume of the pump chamber through this advance or retreat. The float chamber of the carburetor is connected to the pump chamber through an inlet passage having a first check valve, and the pump chamber is accelerated through an outlet passage having a second check valve. Those connected to a nozzle are becoming popular. That is, when the throttle valve moves in the opening direction and the volume of the pump chamber increases, the fuel in the float chamber is drawn into the pump chamber through the inlet passage, and the throttle valve is opened. When the volume of the pump chamber is reduced, the fuel in the pump chamber is guided through the outlet passage to an accelerating nozzle and is injected from the accelerating nozzle into the intake system passage. However, with this type of device, a fixed amount of fuel is discharged each time the acceleration pump operates, so if the fuel discharge amount is set to correspond to sudden acceleration that requires an increase in fuel, it is possible to Sometimes, excess fuel is supplied into the intake system. As a result, the air-fuel mixture becomes unduly rich, resulting in problems such as not only poor emissions and drivability but also reduced fuel economy. As a prior art related to this type of acceleration fuel increase device, as shown in Japanese Patent Publication No. 50-39767, there is a detection means for detecting the magnitude of transient fluctuations in intake pipe negative pressure, and a detection means for detecting the magnitude of transient fluctuations in intake pipe negative pressure. and a fuel injection means for supplying an amount of fuel to the intake system passage in accordance with the magnitude of the voltage output from the control means. There is something like that. However,
This system is designed to supply a large amount of fuel if the fluctuations in the intake pipe negative pressure are large, and to supply only a small amount of fuel if the fluctuations are small. In other words, whether the engine is accelerating from a light load state or from a nearly high load state, if the amount of fluctuation in the intake pipe negative pressure is the same, only the same amount of fuel can be supplied. Therefore, there is a problem in that it is difficult to supply the optimum accelerating fuel according to the characteristics of the carburetor. Therefore, it is difficult to say that this product can sufficiently meet the demand for improvement in emission, drivability, and fuel economy. In addition, as other prior art, Japanese Patent Application Laid-Open No. 54-62424
As shown in the publication, the throttle opening is periodically detected, the current detected value and the previous detected value are subtracted, and the value corresponding to the subtracted value is further corrected based on the engine operating condition. There is also a system in which the acceleration fuel supply amount is determined based on the corrected value. However, with such a device, it is possible to supply fuel to the engine according to the degree of acceleration, but with such a device, it is necessary to constantly perform calculations, and a compensation circuit for correction is required. etc., which makes the control device complicated.
Even when a microcomputer or the like is used, the problem is that its capacity becomes large. (c) Purpose of the Invention The present invention has been made with attention to the above-mentioned circumstances, and it is a method to determine which of a plurality of pre-divided zones the intake pipe negative pressure or throttle opening that is periodically detected belongs to. and the amount of fuel alternatively determined by the zone to which each detected value belongs and the zone to which the next detected value belongs can be supplied to the carburetor. The purpose of the present invention is to provide an accelerating fuel increase device for a carburetor that can improve emission, drivability, and fuel economy without performing calculations or delicate correction processing. . (d) Structure of the invention In order to achieve the above object, the present invention employs the following structure. That is, the accelerating fuel increase device for a carburetor according to the present invention includes a detection means that periodically detects the intake pipe negative pressure or the throttle opening, and a detection means that detects the intake pipe negative pressure or the throttle opening detected by the detection means in advance. Judgment means for determining which of the plurality of divided zones it belongs to, and an amount of fuel that is alternatively determined by the zone to which each detected value belongs and the zone to which the next detected value belongs. and a fuel injection means for supplying an amount of fuel to the carburetor according to the command from the control means, the fuel injection means being selectively determined by the control means. The amount of fuel used in the vehicle is characterized in that it is set and stored in advance at an appropriate value depending on the operating range in which acceleration is performed. (e) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The drawing is a system explanatory diagram of the accelerating fuel increase device according to the present invention, in which 1 is a carburetor of an automobile engine, 2 is a throttle valve of this carburetor 1,
3 is a float chamber, 4 is a vacuum switch device,
5 is a control means for processing the signal output from this vacuum switch device 4; 6 is this control means 5;
This is a fuel injection means that supplies accelerating fuel to the carburetor 1 under control. The vacuum switch device 4 includes a detection means for periodically detecting intake pipe negative pressure, and a determination means for determining to which of a plurality of zones classified in advance the intake pipe negative pressure detected by the detection means belongs. This is the role that the company plays. Specifically, this vacuum switch device 4 includes an idle switch 7 that outputs an idle signal P ₁ when the engine is in an idling state, and a vacuum switch 7 that outputs an idle signal P 1 when the engine is in an idling state, and a vacuum switch 7 that outputs an idle signal P 1 when the engine is in an idling state, and a vacuum switch 7 that outputs an idle signal P 1 when the engine is in an idling state. The first vacuum switch 8 outputs the light load signal _P2 when the intake pipe negative pressure is -300 mmHg, for example.
Medium load signal P ₃ when it shows a value closer to the atmosphere than
and a third vacuum switch 10 that outputs a high load signal _P4 when the intake pipe negative pressure is lower than -150 mmHg, for example, than atmospheric pressure. It becomes. That is, this vacuum switch device 4 outputs the idle signal P1 when the detected intake pipe negative pressure belongs to the idle zone, and outputs the idle signal _P1 when the detected intake pipe negative pressure belongs to the light load zone. in case of,
If the light load signal P ₂ is output and the detected intake pipe negative pressure belongs to the medium load zone, the medium load signal P ₃ is output and the detected intake pipe negative pressure belongs to the high load zone. When the high load signal P4 is present, the high load signal _P4 is output. The control means 5 also includes a central processing unit 12.
, memory 13, and interfaces 14 and 15
The signal P ₁ , P ₂ , P ₃ , P ₄ from each of the switches 7, 8, 9, 10 is input to the interface 14. It is becoming more and more like this. This control means 5 controls each signal P ₁ , P ₂ , P ₃ ,
Each (nth) signal P ₁ , P ₂ , P ₃ , P ₄ that is read from P ₄ at regular intervals and stored in the memory 13
and the next (n+1th) signal P ₁ , P ₂ , P ₃ , P ₄ , and a command is issued to inject an amount of fuel alternatively determined by the comparison. That is,
This control means 5 transmits either a small amount injection command signal A ₁ , a medium amount injection command signal A ₂ or a large amount injection command signal A ₃ to the interface 1 as shown in the following table.
It is programmed so that it can be output sequentially through 5.

[Table] Furthermore, the fuel injection means 6 has an inlet 17 having a check valve 16 connected to the float chamber 3 via an inlet passage 18, and an outlet 19 connected to the check valve 2.
1 _, an electromagnetic acceleration pump 23 opened into the intake passage _1a of the carburetor 1 through an outlet passage 22 having _a Receive each signal A ₁ , A ₂ ,
A driver 24 is provided to drive the acceleration pump 23 at a speed corresponding to _A3 . The acceleration pump 23 is configured to perform a pumping function by moving a piston 27 forward and backward within a cylinder 26 that forms a pump chamber 25 by the urging force of a spring 28 and the electromagnetic attraction force of a solenoid 29.
Further, the driver 24 causes the solenoid 29 to
For example, a pulse voltage of about 20 Hz is applied to move the piston 27 of the acceleration pump 23 forward and backward, and the number of pulses of the applied voltage is made to correspond to the injection command signals A ₁ , A ₂ , A ₃ . By changing the fuel discharge amount of the acceleration pump 23,
It can be adjusted in stages. With such a configuration, when transitioning from idling operation to light load operation, that is, n
At the time of the second sampling, idle switch 7
An idle signal _P1 was output from n+1.
At the time of the nth sampling, if the light load signal _P2 is output from the first vacuum switch 8, or if there is a transition from light load operation to medium load operation, that is, at the time of the nth sampling. A light load signal P ₂ was being output from the first vacuum switch 8, but at the n+1st sampling time, the second vacuum switch 9
When the medium load signal P ₃ is to be output from the control means 5, the small amount injection command signal A ₁ is output from the control means 5. As a result, a pulse voltage of a constant frequency is applied from the driver 24 to the solenoid 29 of the acceleration pump 23, causing the piston 27 to move a small number of times (for example, 4
times or less) and a small amount of fuel flows into the acceleration pump 23.
is supplied to the vaporizer 1 from Also, when transitioning from idling operation to medium load operation, that is,
At the n-th sampling time, the load detection means 4
An idle signal _P1 was output from n+1.
If the medium load signal P ₃ is to be output for the nth time, or if there is a transition from medium load operation to high load operation, in other words, the medium load signal P3 will be output for the nth time.
P ₃ has been output, but if the high load signal P ₄ is to be output at the (n+1)th time, the control means 5 outputs the medium injection command signal A ₂ . As a result, a medium number of pulse voltages (for example, 6 to 8 times) are applied from the driver 24 to the solenoid 29 of the acceleration pump 23, and the piston 27 moves back and forth at a medium speed, so that a medium amount of fuel is transferred to the carburetor. 1. In addition, if there is a sudden transition from idling to high load operation, that is, at the nth sampling time, the idle signal P ₁ is output, but at the n+1 time, the high load signal P ₄ is output. or when there is a sudden transition from light load operation to high load operation, that is, at the nth time, the light load signal P ₂
was being output, but a high load signal was output at the n+1st time.
When P ₄ is to be output, the control means 5 outputs a large amount injection command signal A ₃ .
As a result, the solenoid 29 of the acceleration pump 23
A pulse voltage is applied many times (for example, 10 times or more) to the piston, and the piston moves back and forth many times, thereby supplying a large amount of fuel to the carburetor 1. Therefore, with such a device, it is possible to supply accelerating fuel to the carburetor 1 in an appropriate amount out of the three stages of small, medium, and large amount depending on the degree of acceleration, so that It is possible to supply the rich air-fuel mixture necessary for acceleration, and it is also effective in eliminating the disadvantages of conventional systems, such as deterioration of emissions, drivability, and deterioration of fuel economy due to excessive supply. In particular, this method determines which zone the periodically detected intake pipe negative pressure belongs to each time, and determines the zone to which each (nth) detected value belongs and the next (n+1) detected value. In combination with the zone to which the value belongs, the degree of acceleration and the driving range in which the acceleration occurred are specified, and the corresponding fuel amount is selectively selected, so it is possible to simply determine the degree of acceleration. Compared to the case where the acceleration fuel supply amount is determined solely based on the acceleration fuel supply amount, more appropriate acceleration fuel increase control can be performed. Therefore, the optimum accelerating fuel can be supplied in accordance with the characteristics of the carburetor, and excellent effects can be obtained in that emissions, drivability, and fuel economy can all be improved to a high degree. Furthermore, this device determines which of the pre-divided zones the detected value belongs to, and selectively determines which zone each detected value belongs to and which zone the next detected value belongs to. Since the amount of fuel can be injected, the control means can be significantly simplified compared to those that require complicated calculations and correction processing. As described above, as long as the fuel amount that is alternatively determined is set in advance to an appropriate value according to the driving range in which acceleration is performed and stored, appropriate acceleration can be achieved according to the degree of acceleration. Fuel can be supplied to the carburetor. It should be noted that the present invention is of course not limited to the above embodiments, and the detection means may be an analog intake pressure sensor, or a throttle opening sensor that directly detects the opening of the throttle valve. It may also be a sensor or the like. Furthermore, even when using a vacuum switch or the like, the types of zones are not limited to four types. Further, the control means is not limited to the above embodiments, and may include increasing or decreasing the types of injection command signals, etc.
Various modifications are possible. Further, the fuel injection means is not limited to one using an electromagnetic acceleration pump, and for example, it is possible to change the supply amount of acceleration fuel by controlling the amount of advance of the piston of a conventionally used acceleration pump. It may be something that can be done. (Effects) Since the present invention has the above-described configuration, it is possible to supply an appropriate amount of acceleration fuel according to the degree of acceleration and the driving range in which acceleration is performed without performing complicated calculations or signal correction processing. It is thus possible to provide an accelerating fuel increasing device for a carburetor that can reasonably and efficiently improve emissions, driveability, and fuel economy using simple control means.

[Brief explanation of drawings]

The drawing is a system explanatory diagram showing an embodiment of the present invention. 1... Carburetor, 2... Throttle valve, 4...
... Vacuum switch device (detection means, determination means), 5 ... Control means, 6 ... Fuel injection means.

Claims (1)

[Claims] 1. A detection means for periodically detecting intake pipe negative pressure or throttle opening, and determining to which of a plurality of pre-divided zones the intake pipe negative pressure or throttle opening detected by this detection means belongs. a determination means; a control means for issuing a command to inject fuel in an amount alternatively determined by the zone to which each detected value belongs and the zone to which the next detected value belongs; and a fuel injection means for supplying an amount of fuel to the carburetor according to a command from the means, and the amount of fuel selectively determined by the control means is determined in advance according to the operating region in which acceleration is performed. An accelerating fuel increasing device for a carburetor, characterized in that the fuel is set to an appropriate value and stored in memory.