JPH1077909A - Automatic starter of compound carburetor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the automatic starter of a compound carburetor which is capable of excellent starting of an engine compatible to an engine temperature and performing a warming up. SOLUTION: Single automatic starters are arranged smaller than carburetors in number but more than one. Absolute starting fuel supply quantity at the time of a rise in temperature from a fixed temperature T0 to a fixed temperature T2 of starting fuel S1 supplied to at least two more carburetors C1 and C2 of a district from a first starter is increased more than absolute starting fuel supply quantity supplied to a carburetor of an other district from remaining starters. A supply stoppage temperature of starting fuel supplied from a first starter S1 to the carburetors C1 and C2 of a district is made higher than a supply stoppage temperature of starting fuel supplied from remaining starters to carburetors of other districts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carburetor for controlling the amount and concentration of air-fuel mixture supplied to an engine. Among them, in particular, a plurality of carburetors provided with an intake passage penetrating the carburetor body sideways are arranged, and each of the carburetors has a starting fuel passage, a starting air passage, a starting air passage in a starting valve guide cylinder. The mixture passage is opened, and the opening is movably disposed in the start valve guide cylinder, and the starting fuel is supplied through a plurality of automatic start devices that are opened and closed by a start valve that moves according to the engine temperature. The present invention relates to an automatic starter for a multiple vaporizer.

[0002]

2. Description of the Related Art In a multiple vaporizer in which a plurality of vaporizers are arranged, the number of automatic starters is smaller than the number of vaporizers and a plurality of automatic starters are prepared. Then, the starting fuel controlled by the first automatic starter is supplied to at least two or more carburetors in one group, and the starting fuel controlled by the remaining automatic starters is vaporized in another group. Supplied to the vessel. The starting fuel supply characteristics of the plurality of automatic starting devices have the same specifications. This means that by reducing the number of automatic starters from the number of carburetors, the overall size of the carburetor can be reduced and the degree of freedom in mounting on the engine can be increased. And that the production cost of the carburetor can be greatly reduced by reducing the number of automatic starting devices. It is performed from.

[0003]

According to such a conventional automatic starter for a multiple carburetor, at an extremely low engine temperature T0 (for example, -30.degree. C.) as shown by a solid line in FIG.
A large amount of starting fuel of A (L / H) is supplied, and the supply of the starting fuel is decreased by the engine temperature rising with the progress of the warm-up operation thereafter, and the engine temperature is kept at a constant high temperature T1 (for example, 50 ° C.). At this point, the supply of the starting fuel is stopped. The starting fuel supply characteristic with respect to the change in the temperature of the starting fuel is the same in all the automatic starting devices, whereby the starting fuel having the same characteristic is supplied to all the carburetors. On the other hand, the engine is started in an extremely low temperature state where the engine temperature is around -30 ° C, or is started in a weak low temperature state where the engine temperature is around 0 ° C.
And at various temperature conditions. Here, when the automatic starter is adjusted to a starting fuel supply characteristic suitable for starting at an extremely low temperature, the starting fuel in the weak low temperature state T3 (shown by the solid line in FIG. 3) (for example, 0 ° C.) is B (L / H)
It is supplied and tends to become rich in all cylinders of the engine, which is not preferable for smooth start of the engine. Further, during the warm-up operation after the low-temperature start, the temperature of the air sucked into the engine is higher than the extremely low temperature state, so that it is lower than the constant high temperature T1 (for example, 50 ° C.). It is preferable that the supply of the starting fuel be stopped at the constant temperature T2 (for example, 30 ° C.). However, as shown by the solid line in FIG.
(For example, 50 ° C.), the starting fuel is continuously supplied. According to this, the air-fuel mixture tends to be excessively rich in all cylinders of the engine, which is not preferable for smooth warm-up operation.

On the other hand, it is possible to set the starting fuel supply characteristic supplied from the automatic starting device so as to be suitable for starting in a weak low temperature state, which is shown by a dashed line in FIG. According to this, at the weak low temperature T3 (for example, 0 ° C.), the starting fuel of C (L / H) sufficiently reduced from B (L / H) is supplied, and the starting fuel for the warm-up operation is kept constant. At a temperature T2 (for example, 30 ° C.), the supply is stopped,
Thus, the engine can be satisfactorily performed at the low-temperature start and the warm-up operation after the low-temperature start. However, when the starting fuel supply characteristic shown by the one-dot chain line in FIG. 3 is set, the starting fuel is extremely low in all the cylinders of the engine during the extremely low temperature start at the extremely low temperature T0 (for example, −30 ° C.). As a result, a good engine start cannot be performed. Further, the supply of the starting fuel is performed at the constant temperature T2 (for example,
° C) and stops at a constant high temperature T1 (eg 50 ° C)
Since the starting fuel cannot be supplied continuously until this time, all the cylinders of the engine become thin, and the engine cannot be warmed up satisfactorily.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an automatic starter for a multiple carburetor capable of performing a good engine start and a warm-up operation in accordance with an engine temperature including an engine ambient temperature. The purpose is to obtain.

[0006]

According to an automatic starter for a multiple carburetor according to the present invention, the object is to provide a multiple carburetor in which a plurality of single carburetors are disposed, and a starting valve guide cylinder. A starting fuel passage, a starting air passage, and a starting air-fuel mixture passage are opened, and the openings are movably arranged in a starting valve guide cylinder and are controlled to be opened and closed by a starting valve that moves according to the engine temperature. The automatic starter of the multi-stage carburetor having less than the number of carburetors and a plurality of carburetors, wherein at least two or more groups of carburetors are supplied from the first starter to the group of carburetors. The absolute start-up fuel supply amount when the temperature rises from the constant temperature T0 to the constant temperature T2 is made larger than the absolute start-up fuel supply amount supplied to the carburetors of the other groups from the remaining start-up devices, and further from the first start-up device. Supply of starting fuel to be supplied to a carburetor in a county The stop temperature, is achieved by increasing the supply stop temperature of the starting fuel supplied from the remainder of the starting device to another gun vaporizers.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic starter for a multiple vaporizer according to the present invention will be described below. FIG. 1 is a longitudinal sectional view showing an embodiment of an automatic starting device for a multiple vaporizer according to the present invention.

[0008] C is a vaporizer and is constituted by the following. Reference numeral 1 denotes a carburetor body in which an intake passage 2 penetrates in a horizontal direction, and the intake passage 2 is opened and closed by a throttle valve 4 attached to a shaft 3 rotatably supported by the carburetor body 1. Is done. Float chamber main body 5 is arranged below vaporizer main body 1,
A float chamber 6 is formed by the vaporizer main body 1 and the float chamber main body 5. In the float chamber 6, a float 7, a fuel passage F
A constant fuel level is formed by a valve seat 8 connected to the valve and a float valve 9 that opens and closes the valve seat 8 according to the movement of the float 7. 10 is a fuel system,
The upstream opens into the fuel level, and the downstream opens into the intake passage 2. For example, four such carburetors C are arranged vertically to constitute a multiple carburetor. At this time, the first carburetor C1, the second carburetor C2, and the third carburetor are arranged from top to bottom. C3 and the fourth carburetor C4. Each carburetor is connected to and connected to each cylinder constituting the engine. The engine and cylinder are not shown.

The starting device S is constituted as follows. 20
Is a starting device main body, and a bottom portion 20 is directed toward an upper end 20A.
A bottomed cylindrical start valve guide cylinder 20C having an opening B is opened.
Reference numeral 21 denotes a heat-sensitive responsive body having a heat expansion / contraction material such as paraffin or olefin enclosed therein, and a stroke rod 22 at its lower end for outputting a volume change of the heat expansion / contraction material as a stroke change to the outside. A retainer 23 is urged against the stroke rod 22 by a spring 24 so as to always elastically contact the stroke rod 22. When the stroke rod 22 moves downward, the retainer 2
3 moves downward against the spring force of the spring 24, and when the stroke rod 22 moves upward, the retainer 23 moves upward following the upward movement of the stroke rod 22 by the spring force of the spring 24. I do. That is, the retainer 23 moves synchronously with the stroke rod 22.

[0010] A downstream opening 25A of the starting fuel passage 25 is opened at the bottom 20B of the starting valve guide cylinder 20C. The upstream opening 25B of the starting fuel passage 25 is formed in a starting fuel tank formed in the starting device main body 20. It opens below the fuel level in 26. Then, the starting fuel tank 26 and the fuel level below the float chamber 6 are connected by a starting fuel introduction path 27.

A starting air passage 28 connected to the atmosphere is opened on one side wall of the starting valve guide cylinder 20C.

Further, a starting air-fuel mixture passage 29 is opened on the other side wall of the starting valve guide cylinder 20C. The upstream opening 29A of the starting mixture passage 29 opens to the other side wall of the starting valve guide cylinder 20C.

[0013] Then, the starting valve guide cylinder 20C is opened.
Downstream opening 25A of starting fuel passage 25, starting mixture passage 2
The upstream opening 29A and the starting air passage 28 are controlled to be opened and closed by a starting valve 31 movably arranged in a starting valve guide cylinder 20C. The starting valve 31 is locked via a locking step 23A of the retainer 23, whereby the starting valve 31 and the retainer 23 move synchronously. That is, at the lowest position of the start valve 31, the start fuel passage 25, the start air passage 28, and the start air-fuel mixture passage 29 are closed and held.
5, 28 and 29 are opened.

The number of the starting devices is less than the number of the carburetors C and a plurality of the starting devices are prepared. In this embodiment,
Four carburetors C are prepared, and the starting device S is the first starting device S
One and two second starting devices S2 were prepared. The first starter S1 is arranged near a part of the carburetor composed of the first carburetor C1 and the second carburetor C2.
The upstream of the first starting fuel introduction path 27 is communicated into the float chamber 6 of the second carburetor C2. Further, the downstream of the starting air-fuel mixture passage 29 branches, and each downstream 2 of the starting air-fuel mixture passage 29 is branched.
9B and 29B are connected to an intake passage 2A downstream of the throttle valve 4 of the first carburetor C1 and an intake passage 2A downstream of the throttle valve 4 of the second carburetor C2. The upstream of the starting fuel introduction path 27 may be communicated with the inside of the float chamber 6 of the first carburetor C1.

On the other hand, the second starting device S2 includes a third carburetor C
It is arranged near the remaining part of the carburetor consisting of the third carburetor C4 and the fourth carburetor C4. At this time, the upstream side of the starting fuel introduction path 27 of the second starting device S2 is in the floating chamber 6 of the fourth carburetor C4. Contacted. The downstream of the starting mixture passage 29 branches off, and each downstream 29B, 29B of the branched starting mixture passage 29 branches off.
Is the intake passage 2A downstream of the throttle valve 4 of the third carburetor C3.
And the intake passage 2A downstream of the throttle valve 4 of the fourth carburetor C4.
Will be contacted. The upstream of the starting fuel introduction path 27 may be communicated with the inside of the float chamber 6 of the third carburetor C3.

As described above, the first starting device S1 is disposed near the first carburetor C1 and the second carburetor C2, and the second starting device S1 is disposed near the third carburetor C3 and the fourth carburetor C4. Starting device S
2 are arranged. That is, a plurality of single vaporizers are arranged, and a single automatic starter is arranged in a smaller number than the number of vaporizers and plurally arranged to form an automatic starter of a multiple vaporizer.

According to the automatic starter for a multiple carburetor according to the present invention, the starting fuel supply characteristic of the first starter S1 is set as follows. Extremely low temperature T0 (for example, -30
° C) to a constant high temperature T1 (for example, 50 ° C) when the absolute starting fuel supply amount Q1 is larger than the absolute starting fuel supply amount Q2 in the second starting device S2 under the same temperature condition. This means that, as understood from the solid line in FIG. 2, the starting fuel of A (L / H) is supplied at the extremely low temperature T0 (for example, −30 ° C.) and the starting fuel is supplied at the constant high temperature T1 (for example, 50 ° C.). The supply of fuel is stopped. That is, when the temperature rises from the extremely low temperature T0 (for example, −30 ° C.) to the constant high temperature T1 (for example, 50 ° C.), the absolute start fuel supply amount Q1 indicated by the solid hatching is displayed.
Is supplied to the first vaporizer C1 and the second vaporizer C2.

The starting fuel supply characteristic of the second starting device S2 is set as follows. Extremely low temperature T0 (for example, -3
0 ° C.) to a constant medium temperature T2 (for example, 30 ° C.) when the absolute starting fuel supply amount Q2 is increased by the first starting device S1 under the same temperature condition.
Less. As can be understood from the dashed line in FIG. 2, the starting fuel B (L / L) supplied by the first starting device S1 at the weak low temperature T3 (for example, 0 ° C.).
Starting fuel C (L / H) sufficiently reduced compared to H)
Is supplied. The supply of the starting fuel is performed at a constant high temperature T1.
(For example, 50 ° C.), a constant middle temperature T2 which is a lower temperature.
(For example, 30 ° C.). That is, when the temperature rises from the extremely low temperature T0 (for example, −30 ° C.) to the constant middle temperature T2 (for example, 30 ° C.), the absolute starting fuel supply amount Q2 indicated by the dotted horizontal line is the third carburetor C
3. It is supplied to the fourth carburetor C4.

To summarize the above, the first starting device S1 is
From a very low temperature T0 (for example, -30 ° C.) to a constant high temperature T1
When the temperature rises to, for example, 50 ° C., the amount is gradually decreased, and a large amount of the starting fuel Q1 is supplied to the first carburetor C1,
It is supplied to the second vaporizer C2. On the other hand, when the temperature rises from the extremely low temperature T0 (for example, −30 ° C.) to the constant middle temperature T2 (for example, 30 ° C.), the second starting device S2 gradually reduces the amount, and supplies a small amount of the starting fuel Q2. The gas is supplied to the third carburetor C3 and the fourth carburetor C4.

The supply characteristics of the starting fuel in the starting devices S1 and S2 are the expansion and contraction characteristics of the thermal expansion and contraction material sealed in the thermosensitive body 21. Temperature characteristics of a PTC heater (indicated by P in FIG. 1) arranged in contact with the heat-sensitive element 21 to heat the heat-sensitive element 21. Starting fuel tank 26 volume. A needle valve N integrally attached to the starting valve 31 and inserted into the starting fuel passage 25 to control an effective opening area of the starting fuel passage 25. And so on.

Next, the operation will be described. The starting of the engine in the extremely low temperature state of the engine ambient temperature will be described. The extremely low temperature T0 is, for example, −30 ° C. In such a state, the first starting device S1 supplies a large amount A (L / H) of starting fuel toward the first carburetor C1 and the second carburetor C2, and the second starting device S2 supplies A (L / H). ) Less D
(L / H) starting fuel is supplied to the third carburetor C3 and the fourth carburetor C
Supply to 4. According to the above description, the first and second cylinders (not shown) connected to the first carburetor C1 and the second carburetor C2 are supplied with a rich starting fuel suitable for cryogenic temperatures, so that the first and second cylinders are smoothly supplied. Start of the engine can be performed. On the other hand, in the third cylinder and the fourth cylinder (not shown) connected to the third carburetor C3 and the fourth carburetor C4, the starting of the engine is slightly performed because the reduced starting fuel is supplied. Although the smoothness is lacking, the first cylinder and the second cylinder perform the smooth start, so that the engine as a whole can satisfy the start at the time of extremely low temperature.

After the engine is started, the engine is warmed up.
When the temperature rises to 2 (for example, 30 ° C.), the supply of the starting fuel from the second starting device S2 to the third carburetor C3 and the fourth carburetor C4 is stopped. On the other hand, in the first starting device S1, the supply of the starting fuel is not stopped at the constant medium temperature T2, and the starting fuel is continuously supplied up to the constant high temperature T1 (for example, 50 ° C.). During the warm-up operation,
The starting fuel supplied from the second starting device S2 is stopped at a constant medium temperature T2 (for example, 30 ° C.), but the first cylinder and the second cylinder are still supplied with the starting fuel from the first starting device S1, Since smooth rotation of the first cylinder and the second cylinder is obtained, good warm-up operation of the entire engine can be continuously performed.

When the engine temperature reaches a certain high temperature T1 (for example, 50 ° C.), the warm-up operation of the engine is completed. At this time, the supply of the starting fuel from the first starting device S1 is stopped and the warm-up operation is stopped. Machine operation is completed. (Note that the second starting device S
2, the supply of the starting fuel is already stopped at the constant temperature T2. As described above, during the start-up at extremely low temperatures and the warm-up operation, the first carburetor C1 is operated until the engine sufficiently warms up the appropriate starting fuel through the first starter S1.
To the first cylinder connected to the second carburetor C2 and the second cylinder connected to the second carburetor C2, and the first cylinder and the second cylinder were smoothly operated. 3
Even if the supply of the starting fuel is supplied to the third cylinder connected to the carburetor C3 and the fourth cylinder connected to the fourth carburetor C4 and the supply of the starting fuel is stopped before the completion of the warm-up operation, the engine as a whole is started at a very low temperature and warmed up. Driving can be satisfied.

Next, a description will be given of the starting of the engine in a state where the temperature of the engine atmosphere is slightly low. The weak low temperature T3 is, for example, 0 ° C. In such a state, the first starting device S1
Supplies a large amount of B (L / H) starting fuel to the first carburetor C1,
The fuel is supplied to the vaporizer C2, and the second starter S2 supplies B
A small amount of starting fuel of C (L / H) less than (L / H) is supplied to the third carburetor C3 and the fourth carburetor C4. According to the above description, in the third cylinder connected to the third carburetor C3 and the fourth cylinder connected to the fourth carburetor C4 (shown in FIG. 4), the starting fuel of C (L / H) corresponding to the weak temperature is supplied. Since the engine is supplied, the engine can be started smoothly. Meanwhile, the first
In the first cylinder connected to the carburetor C1 and the second cylinder (not shown) connected to the second carburetor, the start-up of B (L / H) is performed, so that the engine starts slightly smoothly. Although lacking, the smooth start of the third and fourth cylinders allows the engine as a whole to satisfy starting at a low temperature.

After the start of the engine, the engine is warmed up.
When the temperature rises to 2 (for example, 30 ° C.), the supply of the starting fuel from the second starting device S2 to the third carburetor C3 and the fourth carburetor C4 is stopped. On the other hand, in the first starting device S1, the supply of the starting fuel is not stopped at the constant medium temperature T2, and the starting fuel is continuously supplied up to the constant high temperature T1 (for example, 50 ° C.). During the warm-up operation,
The starting fuel supplied from the first starting device S1 is continuously supplied to a constant high temperature T1 (for example, 50 ° C.), but is supplied from the second starting device S2 to the third carburetor C3 and the fourth carburetor C4. The starting fuel is stopped at a temperature T2 (for example, 30 ° C.) during a certain period. According to the above, the first carburetor C1, the second carburetor C1,
In the first and second cylinders connected to the carburetor C2, the starting fuel tends to be rich and the warm-up operation of the engine is slightly less smooth, but the third carburetor C3 and the fourth carburetor C4
In this case, the supply of the starting fuel from the second starting device S2 is stopped, and a good fuel condition can be obtained. Therefore, a good warm-up operation of the entire engine can be performed.

When the engine temperature reaches a certain high temperature T1 (for example, 50 ° C.), the supply of the starting fuel from the first starting device S1 is stopped.

As described above, at the time of starting at a low temperature or at the time of warming-up operation, in particular, the third starting device S2 connects an appropriate starting fuel to the third carburetor C3 and the fourth carburetor C4 via the second starting device S2.
The fuel was supplied to the cylinder and the fourth cylinder, and the cylinder was smoothly operated. Therefore, the rich starting fuel was supplied to the first cylinder via the first starting device S1.
Even if the starting fuel is supplied to the first cylinder connected to the carburetor C1 and the second cylinder connected to the second carburetor C2, and the supply of the starting fuel is performed after the completion of the warming-up operation, the engine as a whole is slightly cold-started and warmed up. Driving can be satisfied.

In the above embodiment, a four-stage vaporizer is used.
The present invention can be applied to a continuous carburetor and a six-vapor carburetor. At this time, two or three automatic starters, which are fewer than the number of vaporizers, are prepared. The arrangement of the multiple vaporizers may be horizontal instead of vertical.

[0029]

As described above, according to the automatic starter for a multiple carburetor according to the present invention, a single automatic starter can automatically start a multiple carburetor having a smaller number of vaporizers and a plurality of carburetors. In the apparatus, a constant temperature T0 of the starting fuel supplied from the first starting device to at least two or more groups of carburetors.
The absolute starting fuel supply amount at the time of temperature rise from the first starting device to the constant temperature T2 is made larger than the absolute starting fuel supply amount supplied from the remaining starting devices to the carburetors of the other groups, and furthermore, the one starting group is supplied from the first starting device to the other group. Since the temperature at which the supply of the starting fuel to the carburetor is stopped is higher than the temperature at which the supply of the starting fuel to the other group of carburetors is stopped from the remaining starting device, the engine is started and warmed up at any engine ambient temperature. Driving was successfully performed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of an automatic starter for a multiple vaporizer according to the present invention.

FIG. 2 is a diagram showing a relationship between temperatures of a first starting device S1 and a second starting device S2 and starting fuel.

FIG. 3 is a diagram showing a relationship between a starting fuel supplied from a starting device and a temperature.

[Explanation of symbols]

 C1 First carburetor C2 Second carburetor C3 Third carburetor C4 Fourth carburetor S1 First starter S2 Second starter T0 Extremely low temperature T1 Constant high temperature T2 Constant medium temperature T3 Low temperature

Claims (1)

[Claims] 1. A multiple carburetor in which a plurality of single carburetors are arranged, and a starting fuel passage, a starting air passage, and a starting air-fuel mixture passage opened in a starting valve guide cylinder, and the openings are connected to the starting valve guide. A single automatic starter that is movably arranged in a cylinder and that is controlled to open and close by a start valve that moves according to the engine temperature,
In the automatic starter for a multiple carburetor having a smaller number and a plurality of carburetors, a constant temperature T0 to a constant temperature of the starting fuel supplied from the first starter to at least two or more carburetors. The absolute start-up fuel supply amount at the time of temperature rise to T2 is made larger than the absolute start-up fuel supply amount supplied from the remaining starter to the carburetor of another group, and further from the first starter to the carburetor of one group. An automatic starter for a multiple carburetor, wherein the supply stop temperature of supplied start fuel is higher than the supply stop temperature of start fuel supplied to carburetors in other groups from the remaining start devices.