JPH05256201A - Fuel increase device for multiple vaporizer - Google Patents

Abstract

(57) [Summary] (Corrected) [Purpose] Regarding the fuel increase device for multiple vaporizers,
The lean air-fuel mixture is suppressed during the high-opening low-speed operation and the acceleration operation, and the air-fuel mixture is positively thickened in a specific operation region where the air-fuel mixture becomes lean. A carburetor 1 having a throttle valve 9 and a venturi portion 11 for mechanically controlling opening / closing of an effective opening area of an intake passage 2.
A fuel inflow passage 17 for pressurizing the fuel in the fuel tank T by the fuel pump P or the like to supply it to the floating chamber 5 and a fuel increase passage 20 branched from the fuel inflow passage, a vehicle speed sensor 27, and a pressure sensor for detecting negative pressure in the intake pipe A control valve 21 for controlling the opening and closing of the fuel increase passage by a control signal from a control circuit 30 to which the output of 28 is input, and fuel increase distribution passages 20A to 20C branched from the fuel increase passage and connected to the intake passage of each carburetor. Becomes
The control valve is operated by a control signal from the control circuit within a predetermined vehicle speed range and a predetermined intake pipe negative pressure range to open the fuel increase passage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vaporizer for controlling the amount and concentration of air-fuel mixture supplied to an engine.
A plurality of carburetors that mechanically control the opening and closing of the effective opening area of the intake passage that penetrates the carburetor body with a throttle valve operated by an accelerator wire, for example, two, three, four, in the horizontal direction, The present invention relates to a fuel increasing device for a multiple vaporizer arranged vertically or in a V shape.

[0002]

2. Description of the Related Art There are the following two types of carburetors which mechanically control the opening / closing of an effective opening area of an intake passage by a throttle valve operated by an accelerator wire. Firstly, a valve shaft is rotatably supported by the carburetor main body across an intake passage passing through the carburetor main body, and a disc-shaped butterfly valve is attached to the valve shaft. A venturi portion is formed in the intake passage upstream of the butterfly valve, and a fuel injection hole is formed in the venturi portion. The fuel injection hole opens below the constant liquid surface of the float chamber. Here, when the driver operates the accelerator wire to rotate the valve shaft, the butterfly valve controls the opening and closing of the effective opening area of the intake passage. (Usually called a butterfly type vaporizer, a butterfly type multiple vaporizer using a plurality of such vaporizers is disclosed in, for example, Japanese Utility Model Publication No. 52-57307.)

Secondly, a sliding valve guide cylinder is provided continuously from the middle part of the intake passage penetrating the carburetor main body to the side, and a cylindrical or rectangular throttle valve is provided in the sliding valve guide cylinder. The venturi portion is formed by the bottom of the throttle valve and the intake passage, and a fuel injection hole is formed in the venturi portion. Here, when the driver operates the throttle wire to move the throttle valve in the sliding valve guide cylinder, the throttle valve controls the opening / closing of the effective opening area of the intake passage (the area of the venturi portion). (Usually called a sliding throttle valve type carburetor, and a sliding throttle valve type multiple vaporizer using a plurality of such carburetors is shown in, for example, Japanese Utility Model Publication No. 53-38754.) According to the butterfly type multiple vaporizer and the sliding throttle valve type multiple vaporizer that mechanically control opening and closing of the effective opening area of the intake passage (the area of the venturi portion) by the throttle valve, there are the following problems. ..

First, when the throttle valve is opened to a high opening and the engine speed is low (high opening low speed operation), the flow velocity of the air flowing through the venturi portion becomes low, and the fuel opening to the venturi portion is opened. The Venturi negative pressure applied to the nozzle hole is weakened. According to this (close to the atmospheric pressure), it becomes difficult to suck sufficient fuel from the fuel injection hole to the venturi portion, which causes a lean mixture, which is not preferable. The phenomenon of leaning of the air-fuel mixture in the high opening and low speed operation becomes more remarkable as the diameter of the intake passage is increased (the diameter of the venturi portion is increased) in order to improve the output of the engine. As a conventional technique aiming to solve the above, a single carburetor is arranged with an air control valve on the upstream side of the throttle valve, and at the time of high opening low speed operation, the output of the throttle valve opening sensor and A technique is known in which the air control valve is controlled in the closing direction by the output of the engine rotation speed sensor. (Shown in Jitsukai Sho 60-70761.)

Secondly, when the throttle valve is suddenly accelerated to a high opening degree in order to rapidly increase the rotation speed from a low opening state, as in the idling operation of the engine, during a rapid acceleration operation of the engine. As a result, the engine is immediately supplied with the increased amount of air by the sudden opening of the throttle valve, but the fuel supply is temporarily delayed by the air inertia, resulting in the lean mixture. Not preferred. This leaning phenomenon of the air-fuel mixture becomes more prominent as the diameter of the intake passage is increased (the diameter of the venturi portion is increased). As a conventional technique aiming to solve the above,
The diaphragm is used to divide the housing into a pump room and an atmosphere room.
In the pump chamber, an intake side check valve is placed inside, and an acceleration fuel inflow path connected to the float chamber and a discharge side check valve inside are placed, and acceleration connected to the intake passage of each carburetor. Open the fuel discharge path, press this diaphragm toward the pump chamber side when the throttle valve opens suddenly to pressurize the pump chamber, and vaporize the acceleration fuel stored in the pump chamber through the acceleration fuel discharge path. There is a so-called acceleration pump device technology in which the fuel is injected and supplied into the intake passage of the device. (Shown in Jitsuko Sho 53-32183.)

[0006]

According to such a conventional technique, there are the following inconveniences. First of all, Shokai Sho 60-70
According to the technology of No. 761, during high speed low speed operation,
Although the throttle valve is kept open at a high opening, the air control valve controls the intake passage in the closing direction by the output signal from the control unit to reduce the effective opening area of the intake passage upstream of the throttle valve. Is. According to this, the intake passage negative pressure in the intake passage including the throttle valve on the engine side of the air control valve rises, and the opening of the needle jet as the main fuel system opening to the venturi section on the engine side from the air control valve. The intake passage negative pressure applied to the portion is increased, so that a larger amount of fuel than the needle jet can be sucked out into the intake passage, and thus leaning of the air-fuel mixture can be prevented. However, since the air control valve operates to close the intake passage and reduces the effective opening area of the intake passage, the amount of air supplied to the engine is reduced, which is not preferable in improving the output of the engine. .. In particular, one of the purposes of adopting the multiple vaporizer is to improve the output of the engine, which is particularly inconvenient in the multiple vaporizer. Further, the air control valve needs to be arranged in each carburetor, which increases the number of parts and the number of assembling steps, which is not preferable, and further hinders the design freedom of the entire carburetor.

Next, the technique of Japanese Utility Model Publication No. 53-32183 is as follows.
The pump chamber is pressurized by the sudden opening operation of the throttle valve, and the acceleration fuel stored in the pump chamber is injected and supplied into the intake passage of each carburetor through the acceleration fuel discharge passage. However, it is difficult to set a long injection fuel injection time to supply the fuel for acceleration from the acceleration pump device into the intake passage of each carburetor (continuous injection from the initial stage to the final stage of acceleration). This is because the diaphragm that pressurizes the pump chamber of the acceleration pump device is mechanically connected to the throttle valve.To increase the acceleration fuel injection time, select the chamber volume of the pump chamber, Select a diaphragm spring that is compressed in the room to urge the diaphragm toward the atmosphere chamber, select the passage diameter of the acceleration fuel intake passage and the acceleration fuel discharge passage, or check the intake side check valve and the discharge side check valve. It takes a lot of time to select a valve closing spring for biasing against the seat, which hinders improvement in development efficiency. Even if the above-mentioned elements are selected, the compression stroke of the diaphragm is uniquely determined by the opening stroke of the throttle valve, so there is a limit to the extension of the acceleration fuel injection time from the initial stage to the final stage of acceleration. Is. Also, during the acceleration operation from the intermediate opening operation of the throttle valve, the diaphragm is already in the state of compressing the pump chamber, and it is difficult to further compress the diaphragm, so supply sufficient acceleration fuel. I couldn't do it.

The fuel amount increasing device for a multiple vaporizer according to the present invention has been made in view of the above, and is provided with a plurality of vaporizers for mechanically controlling the opening / closing of the effective opening area of the intake passage by a throttle valve. In the continuous vaporizer, it is possible to suppress the leaning of the air-fuel mixture during the middle, high opening, low speed operation and acceleration operation of the engine, and to positively thicken the air-fuel mixture in a specific operation region where the air-fuel mixture becomes lean. It is an object to provide a fuel increasing device.

[0009]

According to the fuel increasing device for a multiple vaporizer according to the present invention, in order to achieve the above object, the effective opening area of the intake passage passing through the vaporizer main body is mechanically adjusted by a throttle valve. Multiple vaporizers with open / close control and a plurality of vaporizers with a venturi portion formed in the intake passage; Fuel vaporized by fuel head difference or fuel pump pressurizing the fuel stored in the fuel tank Fuel inflow passage for supplying to a valve seat opening in the float chamber of the container; fuel increase passage branched from the fuel inflow passage; output of a vehicle speed sensor arranged in the fuel increase passage for detecting the speed of the vehicle, and a throttle valve The output of a pressure sensor that detects the negative pressure in the intake pipe (intake pipe negative pressure) connected to the intake passage on the engine side or the engine and the control signal from the control circuit to which the fuel increase passage is opened and closed and the fuel is increased. A control valve for controlling the amount of fuel flowing in the fuel quantity passage; a fuel increase distribution passage that branches from the fuel increase passage downstream of the control valve and is connected to the intake passage of each carburetor; Within the range of the above, and within the range of the negative pressure in the intake pipe determined within the range of the vehicle speed, the control valve is operated by the control signal from the control circuit to open the fuel increase passage.

[0010]

When the vehicle speed is within the predetermined vehicle speed range, and within the range of the negative pressure in the intake pipe defined within the vehicle speed range, the control valve operates by the control signal from the control circuit to increase the fuel amount. Open the passage. According to this, the pressurized fuel in the fuel inflow passage is injected and supplied into the intake passage of each carburetor constituting the multiple vaporizer through the fuel increase passage and the fuel increase distribution passage, and the mixture is diluted. Suppress. On the other hand, if the vehicle speed is outside the specified vehicle speed range, or outside the specified intake pipe negative pressure within the specified vehicle speed range, the fuel increase passage is controlled by the control valve. It is kept closed, and the supply of fuel from each fuel increase distribution passage into the intake passage of each carburetor is suppressed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a fuel increasing device for a multiple vaporizer according to the present invention will be described below with reference to the drawings. (Note that, although the present embodiment shows a sliding throttle valve type triple vaporizer, the carburetor type may be a butterfly type carburetor, and is not limited to the number of carburetors. It is not limited to the placement, the vertical placement, the V-shape, and the like.) First, a single vaporizer C constituting a multiple vaporizer will be described with reference to FIG. Reference numeral 1 denotes a carburetor main body in which an intake passage 2 penetrates the inside thereof, and a sliding valve guide cylinder 3 is continuously provided upward from a substantially middle portion of the intake passage 2 and faces a lower recess of the carburetor main body 1. The float chamber main body 4 is disposed, and the lower recess and the float chamber main body 4 form a float chamber 5. A valve seat 6 is opened in the float chamber 5, and a float valve 7 for controlling the opening and closing of the valve seat 6 is arranged corresponding to the valve seat 6, and the float valve 7 is a float valve arranged in the float chamber 5. Opening / closing driving force is applied to the valve seat 6 by the movement of 8.

A throttle valve 9 for controlling the opening and closing of the effective opening area of the intake passage 2 is movably arranged in the sliding valve guide cylinder 3, and the throttle valve 9 rotates on the carburetor main body 1. The operation shaft 10 is freely supported mechanically by a link and a lever, and the operation lever 12 is integrally attached to the shaft end portion of the operation shaft protruding outside the carburetor body 1. An accelerator wire (not shown) to be pulled by a driver is attached to the operation lever 12. Therefore,
When the driver operates the accelerator wire, the operating lever 12 and the operating shaft 10 rotate, and this is transmitted to the throttle valve 9 via a lever, a link, etc., and the throttle valve 9 opens and closes the intake passage 2. become. Then, the venturi portion 11 is formed by the bottom portion 9A of the throttle valve 9 that opens into the intake passage 2 and the intake passage 2 that faces the bottom portion 9A. The opening area of the venturi portion 11 changes as the throttle valve 9 moves. (Forms a so-called variable venturi)

A jet needle 13 is integrally attached to the bottom portion 9A of the throttle valve 9, and the jet needle 13 is inserted into a needle jet 14 which is a fuel injection hole opening in the venturi portion 11. To be done. The needle jet 14 is connected to the main fuel jet 16 via a mixing nozzle 15 having an air bleed hole 15A, and an annular acceleration well W is formed on the outer circumference of the mixing nozzle 15 described above. In the acceleration well W, a liquid surface having substantially the same height as the constant liquid surface formed in the float chamber 5 is formed, and in the acceleration well W on the liquid surface, a main air passage communicating with the atmosphere is formed. Open. (Main air passage not shown)

On the other hand, the valve seat 6 has a fuel inflow passage 17
Fuel stored in a fuel tank T, which will be described later, is supplied in a pressurized state via the fuel tank T. When the fuel tank T is disposed below the carburetor main body 1, The fuel is pressurized by a fuel pump P, which will be described later, and supplied to the fuel inflow passage 17. On the other hand, when the fuel tank T is arranged above the carburetor main body 1, the fuel in the fuel tank T is different from the fuel head difference. It is pressurized by and is supplied to the fuel inflow path 17. The position of the fuel tank T is not limited. Therefore, when the liquid level in the float chamber 5 is lower than the set liquid level, the float valve 7 opens the valve seat 6 by the float 8, so that the fuel flows from the fuel inflow path 17 into the float chamber 5 through the valve seat 6. And the liquid level in the float chamber 5 rises up to a set constant level, the float valve 7 closes the valve seat 6 with the float 8, so that the float chamber 7 flows through the valve seat 6 from the fuel inflow passage 17. The supply of fuel to the inside of the float chamber 5 is stopped, whereby a constant liquid surface can be formed in the float chamber 5. The above is a conventionally known vaporizer.

In this embodiment, three such carburetors C are arranged laterally. This state is shown in FIG. 2, and for convenience sake, the first carburetor C1, the second carburetor C2, and the third carburetor C2 are shown from the right in the figure.
Let it be vaporizer C3. For example, an operation shaft 10 is connected to the throttle valve 9 in each vaporizer so as to open and close in synchronization. Further, the fuel inflow passage 17 of each carburetor is connected to the fuel tank T, and the pressurized fuel is supplied into the fuel inflow passage 17.

Reference numeral 20 is a fuel increasing passage branched from the fuel inflow passage 17, and a control valve 21 for controlling the opening and closing of the fuel increasing passage 20 is arranged in the fuel increasing passage 20. In the control valve 21 according to the present embodiment, the movable iron core 23 is attracted to the fixed iron core 24 by energizing the solenoid 22, and the valve portion 25 integrally formed with the movable iron core 23 is provided in the fuel increase passage 20 in the valve seat 26. A normally-closed solenoid valve for opening the valve was used.
(This control valve 21 can be appropriately selected as long as it has a function (for example, a motor) that electrically opens and closes the passage even if it is not an electromagnetic valve.) Then, the fuel increase passage 20 on the downstream side of the control valve 21 (specifically, In particular, the fuel amount increase distribution passages 20A, 20B, 20C branch from the fuel amount increase passages 20) downstream of the valve seat 26 toward the respective intake passages 2 of the carburetors C1, C2, C3. The opening positions of the fuel increasing distribution passages 20A, 20B, 20C to the intake passage 2 are within the range of the intake passage 2 or the intake pipe (not shown) connecting the intake passage 2 of the carburetor body 1 and the engine. Not limited. In the present embodiment, the fuel increasing distribution passages 20A, 20B, 20C are opened with the nozzle N on the upstream side (left side in FIG. 2) of the throttle valve 9.

Reference numeral 27 denotes a vehicle speed sensor for detecting the speed of the vehicle equipped with the engine equipped with the carburetor (hereinafter referred to as vehicle speed), and 28 denotes the intake passage 2 on the engine side (right side in FIG. 1) of the throttle valve 9 or A pressure sensor that detects a negative pressure (negative pressure in the intake pipe) in an intake pipe (both not shown) connected to the engine. For example, the pressure sensor includes a pressure conversion element and a hybrid IC that amplifies an output signal of the conversion element. For example, the pressure conversion element is a silicon diaphragm type that utilizes the piezoresistive effect of a semiconductor, a vacuum chamber is provided on one side of the silicon diaphragm, and the engine side from the throttle valve 9 via the negative pressure introduction passage 29 on the other side. The negative pressure in the intake pipe connected to the intake passage 2 or the engine is introduced. The negative pressure introducing path 29 in the present embodiment is the third
The throttle valve 9 of the carburetor C3 was opened to the intake passage 2 on the engine side.

The outputs of the vehicle speed sensor 27 and the pressure sensor 28 are input to a control circuit 30 and are controlled under a predetermined condition of the vehicle speed and the negative pressure in the intake passage 2 on the engine side from the throttle valve 9 or the intake pipe connected to the engine. A control signal for driving the control valve 21 is output from the circuit 30. The control circuit 3 described above
An example of conditions under which the vehicle speed at which the control signal for driving the control valve 21 is output and the negative pressure in the intake pipe will be described. The vehicle speed is within the range of 50 km / hour to 110 km / hour, and A control signal for driving is output from the control circuit 30 to the control valve 21 within the range of the negative pressure in the intake pipe determined within the range of the vehicle speed thus set. More specifically, when the vehicle speed is 50 km / hour, the negative pressure in the intake pipe is in the range of -3 mmHg to -100 mmHg, and when the vehicle speed is 80 km / hour, the negative pressure in the intake pipe is -3 mm.
The range is from Hg to -8 mmHg, and the vehicle speed is 100 km /
At this time, the negative pressure in the intake pipe is in the range of -3 mmHg to -4 mmHg. The above-mentioned condition range is clearly indicated by the hatched range in FIG. 3, but this condition range is appropriately set at the time of setting work of the carburetor for the engine and is not limited to the above condition.

Next, its operation will be described. First, a low opening operation state in which the opening of the throttle valve 9 is relatively low (for example, 3/8 opening or less) will be described. At the time of low opening operation, the venturi portion 11 causes the throttle valve 9 to operate. Is narrowed down to a small opening area by the venturi portion 11 of the small opening, and the flow velocity of air flowing through the venturi portion 11 is increased.
1 and the negative pressure of the intake passage 2 downstream of the venturi portion 11 rises and is maintained, the needle jet 14 as the main fuel system and the bypass hole and pilot outlet hole (not shown) as the low-speed fuel system not shown
1 and a proper fuel is sucked into the intake passage 2 and supplied to the engine from each of the carburetors C1, C2, C3, and the operation of the engine is favorably performed corresponding to the low opening degree of the throttle valve 9 to achieve a desired comparison. It is possible to obtain an extremely low vehicle speed (less than 50 km / hour). According to this, since the vehicle speed is less than 50 km / hour and is outside the predetermined vehicle speed range, the output from the vehicle speed sensor 27 to the control circuit 30 is not generated, and the control circuit 30
Therefore, the control signal for driving the control valve 21 is not output. Therefore, the control valve 21 is in the inoperative state, and the control valve 2
The first valve portion 25 holds the valve seat 26 closed, and the increased fuel is supplied from the fuel increasing passage 20 and the fuel increasing distribution passages 20A, 20B, 20C to the intake passages 2 of the carburetors C1, C2, C3. Never.

Next, the throttle valve 9 is further opened from the low opening operation state (the opening degree of the throttle valve 9 is 3/8 or less), and the middle and high opening operation states (the opening degree of the throttle valve 9 is A description will be given of an operating state in which the load is 3/8 or more) and the load applied to the engine is small or medium.
In such an operating state, the throttle valve 9 is opened to a medium and high opening degree, and the load applied to the engine is not relatively large, so that the engine speed appropriately rises. The flow velocity of the air flowing therethrough is increased, and the negative pressure of the venturi section 11 is sufficiently increased. Appropriate fuel corresponding to the negative pressure is sucked out of the needle jet 14 into the intake passage 2 and is then discharged from the carburetors C1, C2, C3. Since it is supplied to the engine, an appropriate vehicle speed can be obtained according to the throttle valve opening. A concrete example of the relationship between the vehicle speed and the negative pressure in the intake pipe will be described with reference to FIG. 3. When the vehicle speed is 50 km / hour, the negative pressure in the intake pipe exceeds −100 mmHg and the vehicle speed is 80 km.
/ H, the negative pressure in the intake pipe exceeds -8 mmHg, and the vehicle speed is 1
At 00 km / h, the negative pressure in the intake pipe exceeds -4 mmHg. That is, in such an operating state, the negative pressure in the intake pipe with respect to the vehicle speed shown in FIG. 3 rises to a negative pressure outside the hatched range. Therefore, since the pressure sensor 28 does not output to the control circuit 30, the control circuit 30 outputs to the control valve 21
The control signal for driving is not output, and the control valve 21
Is the fuel increase passage 20 and the fuel increase distribution passages 20A, 20
B and 20C are closed and held. As described above, when the throttle valve 9 is in the middle and high opening operation, and the load applied to the engine is small and the operation is in the middle load, the fuel increase passage 2
0 and the fuel is not increased from the fuel increase distribution passages 20A, 20B, 20C, but the negative pressure of the venturi portion 11 is sufficiently increased as described above, so that the proper fuel is supplied from the needle jet 14 as the main fuel system. It is sucked into the venturi section 11 and supplied to the engine from each of the carburetors C1, C2, C3 to satisfy the operation of the engine, and it is possible to obtain a desired medium or high vehicle speed according to the opening degree of the throttle valve.

The fuel amount increasing device for the carburetor according to the present invention has a special function in the following. First, first, the throttle valve 9 has a medium or high opening degree (for example, the opening degree of the throttle valve 9 is 3
/ 8 or more), but the vehicle speed does not rise sufficiently according to the opening of the throttle valve 9. Such a state is a state in which the throttle valve 9 is opened to a medium and high opening degree and a high load is applied to the engine, which corresponds to, for example, a steep ascending grade or a state in which luggage is fully loaded. In such a state, the throttle valve 9 is opened to a medium and high opening degree, while the rotational speed of the engine is reduced due to the high load, and the flow velocity of the air flowing through the venturi portion 11 is also reduced so that the venturi portion 11 is reduced. The negative pressure of is reduced.
(Approaching atmospheric pressure) That is, needle jet 1
4, the amount of fuel sucked into the intake passage 2 is reduced, the air-fuel mixture is diluted, the increase in the engine speed is hindered, and an appropriate vehicle speed with respect to the throttle valve opening cannot be obtained. In this way, not being able to obtain a proper vehicle speed with respect to the throttle valve opening means not being able to obtain a proper rotation speed with respect to the throttle valve opening. It leads to not being able to obtain the proper negative pressure in the intake pipe. Figure 3
For example, when the vehicle speed is 50 km / hour, the negative pressure in the intake pipe becomes -100 mmHg or less, and the vehicle speed is 80 km.
The negative pressure in the intake pipe becomes -8 mmHg or less at / hour, and the negative pressure in the intake pipe becomes -4 mmHg or less at a vehicle speed of 100 km / hour. When such a state is reached, the vehicle speed is detected by the vehicle speed sensor 2
7, the output is input to the control circuit 30, while the negative pressure in the intake pipe is detected by the pressure sensor 28, and the output is input to the control circuit 30.

When the outputs from the vehicle speed sensor 27 and the pressure sensor 28 are input to the control circuit 30, the control circuit 30 outputs a control signal for driving the control valve 21 to the control valve 21. In the control valve 21 that has received the control signal, the movable iron core 23 is attracted to the fixed iron core 24, and the valve portion 25 opens the valve seat 26. According to this, a part of the pressurized fuel supplied into the fuel inflow passage 17 is separated from the fuel inflow passage 17, and the carburetors C1, C2 are connected through the fuel increasing passage 20 and the fuel increasing distribution passages 20A, 20B, 20C. It is immediately injected and supplied into the intake passages 2 of C2 and C3, and together with the fuel sucked into the Venturi section 11 from the needle jet 14 as the main fuel system, the throttle valve 9 opens to medium and high opening degrees. The leaning of the air-fuel mixture of the carburetors C1, C2, C3 during high load operation is suppressed to increase the engine speed, and the vehicle speed rises to an appropriate vehicle speed according to the throttle valve opening. To do. Then, the fuel increase passage 20 and the fuel increase distribution passage 20A,
The supply of the increased fuel into the intake passage 2 of each carburetor via 20B and 20C is carried out within the range of the predetermined vehicle speed within the range of the negative pressure in the intake pipe (in other words, to the throttle valve opening degree). In contrast, the vehicle speed has not risen to a proper speed). Referring to FIG. 3, an example will be described. -3 mmHg to -100 mmH at a vehicle speed of 50 km / hour.
It is within the range up to g and is -3 at a vehicle speed of 80 km / hour.
It is in the range from mmHg to -8mmHg, and the vehicle speed is 100.
In km / h, it is within the range of -3 mmHg to -4 mmHg. Then, the fuel increase distribution channels 20A, 20
When each carburetor receives the fuel supply from B and 20C and the vehicle speed is out of the predetermined vehicle speed range, or when the vehicle speed is out of the predetermined vehicle speed range and out of the predetermined negative pressure range of the intake pipe. If either of these conditions (in other words, that the vehicle speed has risen to an appropriate vehicle speed with respect to the throttle valve opening) is met, the control circuit 30 for driving the control valve 21 outputs The output of the control signal is stopped, the control valve 21 returns to its original position, and the valve portion 25 causes the valve seat 26
The fuel intake passage 20 and the fuel increase distribution passages 20A, 20B, 20C to the intake passage 2 of each carburetor.
To stop the supply of fuel to. In FIG.
As an example, when the vehicle speed exceeds 110 km / hour, the vehicle speed of 50 km / hour is changed from -3 mmHg to -100 mm.
When outside the negative pressure range of the intake pipe of mmHg, the vehicle speed is 80k.
At a vehicle speed of 100 km / h, when the outside of the intake pipe negative pressure range of -3 mmHg to -8 mmHg at m / h
It is when the outside of the negative pressure range in the intake pipe from 3 mmHg to -4 mmHg.

Secondly, during the acceleration operation in which the throttle valve 9 is rapidly opened from a low opening to a middle opening and a high opening, the throttle valve 9 is in a low opening state, and the vehicle speed is 50 km. / It is in a low speed state that does not reach the time. From this state, the driver pulls the accelerator wire to rapidly open the throttle valve 9 of each carburetor to a medium or high opening state and perform an acceleration operation. Here, the behavior of fuel supply to the intake passage 2 when the throttle valve 9 is rapidly opened from a low opening state to a middle opening state is as follows. In the low opening state of the throttle valve 9, the engine speed keeps idling rotation (for example, 1200 RPM) or low rotation, and the vehicle speed is low. In such a state, the fuel is sucked into the intake passage 2 of each carburetor mainly from the low speed fuel system (not shown) such as the bypass hole and the pilot outlet hole, and the low opening low speed operation of the engine is performed. Next, when the throttle valve 9 is in the low opening state,
When the valve is rapidly opened to a high opening, the amount of air flowing in the intake passage 2 is increased at once, and according to this, the negative pressure at the tip of the needle jet 14 opening in the intake passage 2 is temporarily small. Rise to. According to this, the fuel stored in the acceleration well W is sucked into the venturi portion 11 from the needle jet 14 through the mixing nozzle 15 to increase the engine speed. In this state, the fuel in the acceleration well W is sucked out to the venturi section 11 via the needle jet 14 because the intake passage negative pressure applied to the opening of the needle jet 14 temporarily rises slightly, This is because the inflow by the fuel jet 16 is not restricted, and the fuel is already stored in the accelerating well W downstream of the main fuel jet 16 and is easily sucked out. However, even if the fuel in the acceleration well W is sucked out, the stored fuel in the acceleration well W is limited, so that the engine speed is not significantly increased and the vehicle speed is not significantly increased. That is, even if the throttle valve 9 is opened to a medium or high opening degree, it is difficult to immediately increase the vehicle speed according to the throttle valve opening degree. By increasing the capacity of the acceleration well W, it is possible to increase the number of revolutions during acceleration and increase the vehicle speed, but the inner and outer diameters of the mixing nozzle 15 improve the drivability in other operating regions. This is because the capacity of the accelerating well W is inevitably limited because it is determined in consideration. In such a state, in the present invention, the throttle valve 9 is opened from a low opening to a medium opening and a high opening to accelerate the well W.
The rotation speed increases due to the fuel inside, and the vehicle speed increases slightly, but falls within the prescribed vehicle speed range (this is not an appropriate increase in vehicle speed according to the throttle valve opening).
And in the vehicle speed state, the engine speed does not increase sufficiently and is included in the range of the determined negative pressure in the intake pipe,
The output of the vehicle speed sensor 27 and the pressure sensor 28 for detecting the negative pressure in the intake pipe is not properly increased according to the throttle valve opening, and the outputs of the vehicle speed sensor 27 and the pressure sensor 28 are input to the control circuit 30. In response, a control signal for driving is output. According to this, the valve portion 25 of the control valve 21 immediately opens the valve seat 26, so that the fuel pressurized from the fuel increasing passage 20 and the fuel increasing distribution passages 20A, 20B, 20C is in the intake passage 2 of each carburetor. It is injected and supplied to the vehicle to suppress the leaning of the air-fuel mixture during the acceleration operation and to effectively increase the rotation during the acceleration operation, and the vehicle speed can be increased according to the throttle valve opening. .. Then, the fuel amount increase passage 20 and the fuel amount increase distribution passage 20 to which each vaporizer is applied.
When fuel is supplied from A, 20B, and 20C, the engine speed sufficiently rises, the vehicle speed appropriately rises in accordance with the throttle valve opening, and the intake pipe negative pressure at that vehicle speed rises sufficiently. The output of the control signal from the control circuit 30 to the control valve 21 is stopped, and the fuel supply from the fuel increasing passage 20 and the fuel increasing distribution passages 20A, 20B, 20C is cut off. Is sufficiently increased and the vehicle speed is appropriately increased in accordance with the throttle valve opening. Therefore, a large negative pressure acts on the needle jet 14 as the main fuel system. Fuel suitable for operation is supplied from the needle jet 14 to the intake passage 2 of each carburetor.
I was able to suck it inside. The acceleration operation described above will be described with reference to a specific example with reference to FIG. 3. When the throttle valve 9 is at a low opening of 2/8, the throttle valve 9 is rapidly moved to 4/8 from a state where the vehicle speed is 30 km / hour. When the vehicle speed is 60 km / h and the negative pressure in the intake pipe is -10 mmHg when the vehicle is opened to an intermediate opening.
If so, (the throttle valve 9 was opened to the intermediate opening, but the vehicle speed increased only to 60 km / hour)
The vehicle speed sensor 27 and the pressure sensor 28 detect this state, the outputs of the sensors 27 and 28 are input to the control circuit 30, and the control circuit 30 outputs a signal for driving the control valve 21. According to this, the fuel is immediately supplied from the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B, 20C toward the intake passage 2 to each carburetor, the leaning of the air-fuel mixture is suppressed, and the rotation of the engine is increased. The vehicle speed can be accelerated and increased according to the throttle valve opening. When the rotation speed rises, the vehicle speed rises 70 km / hour according to the throttle valve opening and the intake pipe negative pressure rises above -13 mmHg (the throttle valve 9 is held at the 4/8 opening, The negative pressure in the intake pipe rises due to the increase of the pressure.) The output from the pressure sensor 28 to the control circuit 30 is stopped (vehicle speed 70 km /
At this time, the pressure sensor 28 outputs toward the control circuit 30 within the range of the negative pressure in the intake pipe of −3 mmHg to −13 mmHg).
To the intake passage 2 of each carburetor from the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B, 20C.
The supply of fuel to is stopped.

Further, even during an intermediate acceleration operation in which the throttle valve 9 is opened at an intermediate opening, for example, from a 4/8 opening to a 6/8 opening, the negative pressure of the venturi section 11 does not immediately increase,
There is a case where the increase in the rotation speed is suppressed and the vehicle speed does not accelerate and increase to a desired speed. Even in such a state, the control valve 21 performs the above operation by the signal output from the control circuit 30, so that the intermediate acceleration operation can be improved. Can be planned. Figure 3
With a specific example, the throttle valve opening 4 /
8. When the vehicle speed is 70 km / hour and the intake pipe negative pressure is -20 mmHg, the throttle valve 9 is rapidly opened to a high opening of 6/8 from the middle operation of the throttle valve. When the vehicle speed is 80 km / hour, the intake pipe has a negative pressure. If the pressure becomes -6 mmHg, the vehicle speed sensor 27 and the pressure sensor 28 detect this state (that the throttle valve 9 was opened to 6/8 but the vehicle speed increased only to 80 km / hour). The outputs of the sensors 27 and 28 are control circuits 30.
And a signal for driving the control valve 21 is output from the control circuit 30. According to this, the fuel is immediately supplied from the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B, 20C toward the intake passage 2 of each carburetor, the leaning of the air-fuel mixture is suppressed, and the engine speed is increased. As a result, the vehicle speed can be accelerated and increased according to the throttle valve opening. When the rotation speed increases, the vehicle speed increases by 90 km / hour according to the throttle valve opening and the negative pressure in the intake pipe exceeds -6 mmHg (the throttle valve 9 is held at the 6/8 opening, and the rotation increases). By doing so, the negative pressure in the intake pipe rises) The output from the pressure sensor 28 to the control circuit 30 is stopped (vehicle speed 90 km /
At this time, the pressure sensor 28 outputs toward the control circuit 30 within the range of the negative pressure in the intake pipe of −3 mmHg to −6 mmHg), whereby the output from the control circuit 30 to the control valve 21 is stopped, and the fuel increase passage 20 and The fuel supply to the intake passage 2 of each carburetor is stopped from the fuel increasing distribution passages 20A, 20B, 20C.

Further, the control signal output from the control circuit 30 to the control valve 21 is a drive pulse having the energization time Ti, and the vehicle speed is determined within the predetermined vehicle speed range and within the vehicle speed range. Within the range of the negative pressure in the intake pipe, when the vehicle speed is constant, the energization time Ti is shortened according to the increase in the negative pressure in the intake pipe to increase the fuel flow from the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B, 20C. When the amount of fuel supplied to the intake passage 2 of each carburetor is decreased, and while the vehicle speed is increasing, the energization time Ti is shortened in accordance with the increase of the negative pressure in the intake pipe to increase the fuel increase passage 20. It is advisable to reduce the amount of fuel supplied from the fuel increase distribution passages 20A, 20B, 20C toward the intake passage 2 of each carburetor. This state is clearly shown in FIG. 4. In FIG. 4, the mesh range has the largest amount of fuel supplied from the control valve 21 (referred to as a large flow rate), and the solid line hatching range has a large amount of fuel following the mesh range ( Medium flow rate), and the amount of fuel in the dotted hatching range is second only to the solid line hatching range (small flow rate). According to the above, for example, at a constant vehicle speed of 50 km / hour, negative pressure in the intake pipe from −3 mmHg to −10 mm
In the Hg range, a large amount of fuel increase correction is performed,
The medium flow rate fuel increase correction is performed in the intake pipe negative pressure range of -10 mmHg to -30 mmHg, and the small flow rate fuel increase correction is performed in the intake pipe negative pressure range of -30 mmHg to -100 mmHg. According to this, as the negative pressure in the intake pipe decreases (the negative pressure decreases), it becomes difficult to suck the fuel from the venturi portion 11 into the intake passage 2, so that a large amount of fuel increase correction is performed toward each carburetor. Since this is performed, the air-fuel mixture supplied to the engine is properly controlled, and therefore, there is an extremely great effect in terms of operability of the engine, emission of harmful exhaust gas, and fuel economy. Such an operating state occurs when the engine speed is constant (the vehicle speed is constant) and the load applied to the engine changes. As the load increases, the opening degree of the throttle valve 9 increases and the intake pipe Negative pressure decreases, and as the load decreases, the opening of the throttle valve 9 decreases and the negative pressure in the intake pipe increases. Thus, as the load increases, the fuel increase passage 20 and the fuel increase distribution passage 20A,
The amount of fuel supplied to the intake passage 2 of each carburetor via 20B and 20C can be increased, and high load operation can be appropriately handled.
(In other words, as the load decreases, the fuel increase passage 2
It is possible to reduce the amount of fuel supplied to the intake passage 2 of each carburetor via 0 and the fuel increase distribution passages 20A, 20B, 20C, and it is possible to appropriately cope with low load operation. )

Further, the acceleration drivability of the engine can be further improved. For example, considering the acceleration operation of an engine in which the throttle valve 9 is rapidly opened from a low opening to a high opening, as described above, the throttle valve 9 is low opening and the vehicle speed is 30 km.
From the state of / hour, the throttle valve 9 is opened and, for example, the vehicle speed is 6
When the negative pressure in the intake pipe becomes −10 mmHg at 0 km / hour, a signal for driving the control valve 21 is output from the control circuit 30. According to this, the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B, 20C Fuel is supplied to the intake passage 2 of each carburetor, the engine speed increases, the vehicle speed increases according to the opening of the throttle valve to 70 km / hour, and the acceleration ends. When the vehicle speed increases from 60 km / hour to 70 km / hour, the negative pressure in the intake pipe increases from -10 mmHg to more than -13 mmHg, but from -10 mmHg to -13.
When the negative pressure in the intake pipe rises to mmHg, the fuel supplied from the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B, 20C into the intake passage 2 of each carburetor is of medium flow rate at the initial stage. Therefore, the flow rate can be automatically reduced to a small flow rate as the vehicle speed and the negative pressure in the intake pipe increase. The reason why the supply of fuel from the fuel quantity increasing passage 20 is reduced as the acceleration progresses is that the negative pressure in the intake pipe increases as the acceleration progresses, and the suction of the fuel from the needle jet 14 increases. As described above, since the proper fuel correction can be performed for the acceleration operation of the engine, the acceleration drivability can be further improved.

Further, the large flow rate within the mesh range described above,
When the control valve 21 is controlled by arbitrarily changing the energization time Ti within each range of the medium flow rate in the solid line hatching range and the small flow rate in the dotted line hatching range, the fuel increase passage 20 and the fuel increase distribution passages 20A, 20B are controlled. , 20
The control of the fuel supplied into the intake passage 2 of each carburetor can be made more precise and finer than that of C. Also, the control valve 21
May be a linear solenoid valve in which the valve portion 25 moves linearly with respect to the valve seat 26 so that the opening area thereof can be continuously changed.

Reference numeral 31 is a pressure regulator for always maintaining the pressure of the fuel flowing in the fuel increasing passage 20 at a constant pressure, which is composed of a metal housing, the interior of which is constituted by a diaphragm and a fuel chamber and a spring. The fuel in the fuel increase passage 20 upstream of the fuel inflow passage 17 or the valve seat 26 flows into the fuel chamber from the inlet and pushes up the valve through the diaphragm to balance with the spring at the set pressure. The remaining fuel is returned to the fuel tank T, while the spring chamber is connected to the intake passage 2. According to this, since the fuel pressure flowing in the fuel increasing passage 20 is always kept constant, the controlled fuel amount is uniquely determined by the opening of the control valve 21, and the fuel increasing passage 20 and the fuel increasing distribution passage 20A. , 20B, 20C, the fuel supplied toward the intake passage 2 could be accurately controlled.
(Note that the pressure regulator 31 itself is publicly known and the details are not shown.)

Considering the fuel quantity increasing passage 20, first, the inlet may be directly connected to the fuel tank T located above the carburetor without branching from the fuel inflow passage 17, or from the carburetor. Fuel tank T in the lower position
It may be directly connected to a fuel pump via a second pump (not shown), or the fuel increasing distribution passages 20A, 20 corresponding to the outlets thereof.
B and 20C may be the intake passage 2 or an intake pipe (not shown), but particularly when opened to the intake passage 2 on the downstream side (right side in FIG. 1) of the throttle valve 9, the fuel increase distribution passage 20 is formed.
The time required for the fuel supplied from A, 20B, 20C to the intake passage 2 to reach the engine is further shortened, and the fuel supplied into the intake passage 2 does not collide with the throttle valve 9, the needle jet 14, etc. It is supplied, and the responsiveness can be improved. Further, although the sliding throttle valve type carburetor is used in the above embodiment, the same effect can be obtained in the butterfly type carburetor.

Further, in the embodiment shown in FIG. 5, among the vaporizers forming the multiple vaporizer, the vaporizer equipped with the acceleration pump device is arranged, and the first vaporizer C1 and the second vaporizer are provided. Bowl C2
Uses the vaporizer shown in FIG. 1 and uses the third vaporizer C3 as a vaporizer equipped with an acceleration pump device. (Note that the same structural parts as those of the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals and the description thereof will be omitted.) First, FIG. 6 shows a carburetor C3 equipped with an acceleration pump device.
Will be explained. An acceleration pump device 50 has the following configuration. That is, 51 is the acceleration fuel pump chamber 52.
The acceleration fuel pump chamber 52 is connected to the inside of the floating chamber 5 and the suction side check valve 54 is disposed inside the acceleration fuel suction passage 55.
And one end of which is connected to the intake passage 2 through the acceleration nozzle 56, and the acceleration fuel discharge passage 58 in which the discharge-side check valve 57 is arranged is opened, and the diaphragm 51 is pressed toward the atmosphere chamber 53 side. The diaphragm spring 59 is contracted. Then, the opening operation of the throttle valve 9 is performed by the operation lever 1
2, it is added to the diaphragm 51 via the link 60 and the pump lever 61. That is, when the throttle valve 9 is opened, the diaphragm 51 reduces the chamber volume of the acceleration fuel pump chamber 52 by the pump lever 61 to pressurize the acceleration fuel pump chamber 52, whereby the acceleration fuel pump chamber 5 is pressurized.
The fuel for acceleration stored in 2 is injected and supplied into the intake passage 2 through the acceleration nozzle 56.

Then, a carburetor equipped with an acceleration pump device is used as the third carburetor C3 to form a multiple carburetor as shown in FIG. (The first vaporizer C1 and the second vaporizer C2 do not have an acceleration pump device.) The acceleration fuel distribution passages 58A, 58B, 58C are branched from the acceleration fuel discharge passage 58 of the third vaporizer C3, and each of these acceleration fuels. Distribution channels 58A, 58B and 58C are provided for the vaporizers C1 and C, respectively.
The intake channels 2 of C2 and C3 are connected to each other via an acceleration nozzle 56. A discharge-side check valve 57 is arranged in each of the acceleration fuel distribution paths 58A, 58B, 58C. Further, the outlets on the downstream side of the fuel increasing distribution passages 20A, 20B, 20C branched from the fuel increasing passage 20 similar to the first embodiment shown in FIG. 2 have an acceleration nozzle 56 and a discharge side check valve 57. The acceleration fuel distribution paths 58A, 58B, and 58C are opened.

According to the above structure, the fuel increase passage 20 by the control valve 21 and each fuel increase distribution passage 20A, 20
The supply of the increased amount of fuel to B and 20C is similar to that of the first embodiment, but during acceleration operation, fuel is supplied from the acceleration well W to the intake passage 2 via the needle jet 14 especially at the initial stage of acceleration. In addition to the above, the acceleration fuel from the acceleration pump device 50 could be supplied together, so that the rise of rotation in the initial stage of acceleration could be performed more smoothly. That is, in the first embodiment, the fuel increase passage 20 and each fuel increase distribution passage 20A, 20B, 2 during the acceleration operation.
Looking at the behavior of the fuel supplied from 0C to the intake passage 2 of each carburetor, the throttle valve 9 is mechanically opened from the low opening state and rises to a constant vehicle speed range, and is within the vehicle speed range. When a predetermined negative pressure in the intake pipe is reached, a signal is output from the control circuit 30 to the control valve 21. The change in the amount of air in the venturi portion 11 → the change in the negative pressure in the venturi portion 11 (the negative pressure in the intake pipe) Of the fuel) → suction of fuel from the needle jet 14 → increased rotation → increased vehicle speed → vehicle speed sensor 27
There is a time delay with the detection of the vehicle speed by the control valve 21.
Via the fuel increase passage 20 and each fuel increase distribution passage 20
There is a slight delay in the fuel supply from A, 20B, 20C to the intake passage 2 of each carburetor. On the other hand, according to the second embodiment, when the throttle valve lever 12 is rotated and the acceleration operation is started, the rotation of the throttle valve lever 12 causes the link 6 to rotate.
0, diaphragm 5 synchronously via pump lever 61
1, the acceleration fuel pump chamber 52 is compressed, and the acceleration fuel is vaporized from the acceleration fuel pump chamber 52 through the acceleration fuel discharge passage 58, the acceleration fuel distribution passages 58A, 58B, 58C, and the acceleration nozzles 56. Since the fuel can be immediately supplied to the intake passage 2 of the fuel injection system 2, a time delay in fuel supply from the fuel increasing passage 20 and the fuel increasing distribution passages 20A, 20B, 20C during the acceleration operation can be prevented, and the initial acceleration can be achieved. It was possible to improve the acceleration performance in.

Further, each fuel increase distribution passage 20A, 20B, 2
The downstream side of 0C, especially the discharge side check valve 57 and the acceleration nozzle 5
6, the acceleration fuel distribution passages 58A, 58B, 58C are opened to the fuel increase distribution passages 20A, 20B due to the pressing load of the check valve spring S pressing the discharge side check valve 57 against the discharge valve seat. , 20C is not subject to any restriction on the fuel pressure. That is, the discharge side check valve 57
When the fuel increase distribution passages 20A, 20B, 20C are opened in the accelerated fuel discharge passage on the side of the acceleration fuel pump chamber 52, the pressure of the fuel flowing in the fuel increase distribution passages 20A, 20B, 20C is pressed by the check valve spring S. If the load is not larger than the load, it is impossible to supply the increased amount of fuel through the acceleration fuel distribution passages 58A, 58B, 58C, and the discharge pressure of the fuel pump P is increased or the fuel head difference is sufficiently increased to increase the fuel increase passage 20. It is necessary to increase the pressure of fuel flowing inside.

Furthermore, since the openings of the fuel increasing distribution passages 20A, 20B and 20C which are opened to the intake passage 2 of the carburetor main body 1 are formed in the limited carburetor structure, the degree of freedom in design is small. However, the acceleration nozzle 5 that has already been drilled
According to the use of the acceleration fuel distribution passages 58A, 58B, 58C connected to No. 6, the fuel increase distribution passages 20A, 20B, 2
It becomes easy to rotate 0C.

In the first and second embodiments, the amount of the increased fuel injected and supplied from the fuel increase passage 20 into the intake passage 2 is determined by the setting work with the engine. Since a small amount of fuel of about 5 cc / min is sufficient, a passage diameter smaller than the effective passage diameter of the fuel increasing passage 20 is provided in the fuel increasing passage 20 on the downstream side (the side discharging to the intake passage 2) of the control valve 21. When the control jet J is arranged and the fuel injection passage 20 and the fuel increase distribution passages 20A, 20B, 20C are used to control the injection fuel amount into the intake passage 2 of each carburetor, the control jet J can be accurately controlled. This makes it easier to control the increased fuel.

[0036]

As described above, the fuel quantity increasing device for a multiple vaporizer according to the present invention has the following effects. In a multiple carburetor that mechanically controls opening / closing of an effective opening area of an intake passage by a throttle valve, a range of a negative pressure in an intake pipe defined within a range of a vehicle speed and within the range of the vehicle speed. Each vaporization of the fuel that is positively pressurized from the fuel increase distribution channel, which does not depend on the negative pressure of the Venturi section, during the middle or high opening operation of the throttle valve Since it was possible to suppress the dilution of the air-fuel mixture by supplying it to the intake passage of the reactor, the setting work of the multiple vaporizer was extremely easy and the engine performance could be significantly improved. During acceleration operation of the engine, the rotation of the engine is increased even though the throttle valve is rapidly opened from a low opening to medium and high openings, or the throttle valve is rapidly opened to a high opening from a middle opening. Does not rise sufficiently and an appropriate vehicle speed corresponding to the opening of the throttle valve cannot be obtained, the fuel positively pressurized from the fuel increase distribution passage is supplied to the intake passage of each carburetor. Since the lean air-fuel mixture can be prevented during the acceleration operation, the acceleration performance of the engine can be improved. Moreover, according to the use of the acceleration pump device and the fuel amount increasing device in combination, the acceleration fuel amount is supplied from the fuel increase distribution path together with the supply of the acceleration fuel from the acceleration pump device, especially during the period from the initial stage to the middle period to the final stage of acceleration. Since the pressurized fuel can be supplied, the acceleration of the engine can be further improved. The control of the fuel amount in the fuel increase passage by the control valve is performed in a constant vehicle speed range within a predetermined vehicle speed range and within a predetermined negative range in the intake pipe negative pressure within the vehicle speed range. Therefore, according to the fact that the fuel amount is reduced in accordance with the increase in the negative pressure in the intake pipe and the fuel amount is reduced in accordance with the increase in the negative pressure in the intake pipe when the vehicle speed is increasing, The fuel control characteristics could be accurately matched to the requirements of the engine within an extremely short time, and the engine performance could be significantly improved and the development efficiency could be significantly improved. According to the fact that the inlet side of the fuel increase passage is opened to the fuel inflow passage and the fuel increase distribution passage branched from the fuel increase passage is opened to the accelerated fuel distribution passage downstream of the discharge side check valve of each carburetor, Since the accelerated fuel distribution passage of the drilled acceleration pump device can be used as a part of the fuel increase distribution passage, the degree of freedom in designing the carburetor can be increased. Further, the discharge pressure of the increased fuel from the fuel increase distribution passage does not have any influence on the closing force of the discharge side check valve. The discharge pressure of the increased fuel can be optimally set. By opening the other end on the outlet side of each fuel increase distribution passage into the intake passage on the engine side from the throttle valve, the distance between the opening of the fuel increase distribution passage to the intake passage and the engine is shortened. The fuel can be supplied instantaneously, and the collision of the fuel with the jet needle, the throttle valve and the like after being injected into the intake passage can be reduced, so that the dynamic characteristics of the engine can be improved. According to the fact that the pressure of the fuel flowing through the fuel increase passage is controlled to a constant fuel pressure by the pressure regulator, the amount of fuel supplied from each fuel increase distribution passage into the intake passage of each carburetor is uniquely determined by the control valve. Therefore, accurate fuel supply is possible.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a single vaporizer that constitutes a multiple vaporizer and does not have an acceleration pump device.

FIG. 2 is an overall system diagram including a vertical cross-sectional view showing a first embodiment of a fuel increasing device for a multiple vaporizer according to the present invention in which a plurality of vaporizers shown in FIG. 1 are arranged.

FIG. 3 is a diagram showing an example of a range in which an output for driving is output from a control circuit to a control valve in a relationship between a vehicle speed and a negative pressure in an intake pipe.

FIG. 4 is a diagram showing another example of a range in which an output for driving is output from the control circuit to the control valve in the relationship between the vehicle speed and the negative pressure in the intake pipe.

FIG. 5 is a vertical cross-sectional view showing a second embodiment of the fuel increasing device of the multiple vaporizer according to the present invention, in which the vaporizer having the acceleration pump device is arranged in the vaporizer constituting the multiple vaporizer. It is a whole system diagram including.

FIG. 6 is a vertical cross-sectional view of a single vaporizer including the acceleration pump device shown in FIG.

[Explanation of symbols]

 2 Intake passage 5 Float chamber 6 Valve seat 9 Throttle valve 11 Venturi part 14 Needle jet 17 Fuel inflow passage 20 Fuel increase passage 20A, 20B, 20C Fuel increase distribution passage 21 Control valve 27 Vehicle speed sensor 28 Pressure sensor 30 Control circuit 31 Pressure regulator 50 acceleration pump device 56 acceleration nozzle 57 discharge side check valve 58 acceleration fuel discharge passage 58A, 58B, 58C acceleration fuel distribution passage T fuel tank P fuel pump J control jet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display area F02M 13/02 G 9038-3G

Claims (6)

[Claims] 1. A multiple carburetor in which a plurality of carburetors, in which a venturi portion is formed in the intake passage, are arranged and the effective opening area of the intake passage passing through the carburetor body is mechanically controlled by a throttle valve. A fuel inflow passage for pressurizing the fuel stored in the fuel tank by a fuel head difference or a fuel pump and supplying it to a valve seat opening in the floating chamber of each carburetor; and an increase in fuel amount branched from the fuel inflow passage. A passage and a pressure sensor that is disposed in the fuel increase passage and that detects the output of a vehicle speed sensor that detects the speed of the vehicle and the negative pressure in the intake passage connected to the intake passage or the engine from the throttle valve to the engine (negative pressure in the intake pipe) And a control valve for controlling the amount of fuel flowing in the fuel increasing passage by controlling the opening and closing of the fuel increasing passage by a control signal from a control circuit to which is input; Within the range of the vehicle speed within which the vehicle speed is set, and within the range of the negative pressure in the intake pipe set within the range of the vehicle speed. In the fuel quantity increasing device of the multiple vaporizer, the control valve is operated by the control signal from the control circuit to open the fuel quantity increasing passage. 2. A carburetor in which an effective opening area of an intake passage passing through the carburetor main body is mechanically controlled by a throttle valve and a venturi portion is formed in the intake passage, and an intake passage passing through the carburetor main body. Throttle valve that mechanically controls the opening and closing of the effective opening area of the valve, the venturi portion formed in the intake passage, and the acceleration fuel pump chamber that is mechanically compressed in conjunction with the opening operation of the throttle valve. A carburetor having an accelerating pump device for injecting accelerating fuel from an accelerating fuel discharge passage, and a multiple carburetor comprising: an accelerating fuel branching passage branched from the accelerating fuel discharge passage and connected to an intake passage of each carburetor. And; a fuel inflow passage for supplying the fuel stored in the fuel tank to a valve seat opening in the floating chamber of each carburetor by pressurizing the fuel with a fuel head difference or a fuel pump; a fuel branched from the fuel inflow passage Increase passage And; of a pressure sensor that is arranged in the fuel increase passage and detects the output of a vehicle speed sensor that detects the speed of the vehicle and the negative pressure in the intake pipe connected to the intake passage or the engine from the throttle valve (intake pipe negative pressure). An output and a control valve for controlling the opening and closing of the fuel increase passage by a control signal from the control circuit and controlling the amount of fuel flowing in the fuel increase passage; and a branch from the fuel increase passage downstream of the control valve, And a fuel increase distribution passage that is connected to the intake passage of each carburetor; and the control is performed within a range of the vehicle speed within which the vehicle speed is set, and within a range of the negative pressure in the intake pipe set within the range of the vehicle speed. A fuel increasing device for a multiple vaporizer in which a control valve is operated by a control signal from a circuit to open a fuel increasing passage. 3. The control of the amount of fuel in the fuel increase passage by the control valve is performed within a predetermined vehicle speed range and within a predetermined range of the vehicle speed range of a negative pressure in the intake pipe. When the vehicle speed is constant, the amount of fuel is reduced in accordance with the increase in the negative pressure in the intake pipe, and when the vehicle speed is increased, the amount of fuel is reduced in accordance with the increase in the negative pressure in the intake pipe. The fuel amount increasing device for a multiple carburetor according to claim 1 or 2. 4. The fuel amount increasing apparatus for a multiple carburetor according to claim 2, wherein the fuel increasing distribution passage is opened to each acceleration fuel distribution passage downstream of the discharge side check valve. 5. The fuel amount increasing device for a multiple vaporizer according to claim 1, wherein an outlet side of the fuel amount increasing distribution passage is opened in each intake passage on the engine side of the throttle valve. 6. The fuel amount increasing device for a multiple vaporizer according to claim 1, wherein the fuel pressure flowing through the fuel amount increasing passage is controlled to a constant fuel pressure by a pressure regulator.