JP2560087B2 - Multiple cylinder engine carburetor system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention is a so-called carburetor in which a plurality of carburetors are connected and a cam chain driving member such as a timing chain or a timing belt is arranged between cylinders. More particularly, the present invention relates to a structure in which an intake pipe connecting each carburetor unit and an engine can be shortened.

[Conventional technology]

For example, a multi-cylinder engine for a motorcycle may employ a continuous carburetor device in which as many carburetor units as the number of cylinders are connected in parallel. Such a continuous carburetor device generally has a structure in which the throttle valve of each carburetor unit is controlled to be opened and closed by one throttle cable. In this case, in order to tune the carburetors with certainty, it is necessary to align the axes of the throttle valves with each other in a straight line. For that purpose, the carburetors are connected with high rigidity. There is a need.

Therefore, conventionally, the respective carburetors alone are connected to each other by connecting bolts to connect the engine-side connecting portions and the anti-engine-side connecting portions, which are formed at positions substantially opposite to each other with the throttle valve shaft interposed therebetween, to each other. It is general to increase the joint rigidity of the.

[Problems to be solved by the invention]

By the way, especially in a high-revving engine, it is important to reduce the length of the intake pipe that connects each carburetor unit and the engine so that the carburetor device is mounted as close to the engine as possible. desirable. However, when the conventional continuous carburetor device is mounted on a center drive type engine, the connecting bolt on the engine side interferes with the timing belt accommodating chamber portion of the cylinder head. However, there is a limit, and there is a problem that the intake pipe length cannot be sufficiently shortened in the end.

[Means for solving problems]

According to the present invention, a plurality of carburetors are connected in parallel, and a throttle cable is arranged between any of the carburetors, and a throttle is provided in a multi-cylinder engine having a camshaft drive member accommodating chamber between cylinders. In a continuous carburetor device in which a cable is installed so as to face the accommodation chamber, a left and right first connection in which the engine-side connection portions of the carburetor single bodies on the left and right of the throttle cable are divided into two parts. The carburetors are connected and fixed to each other, and the anti-engine side connecting portions of all the carburetors are connected and fixed to each other with one second connecting bolt, and the guides sandwich the guides by the cable guides that guide the throttle cables. The feature is that the vaporizers are fixed together.

[Action]

In the continuous carburetor device according to the present invention, the left and right carburetor units of the throttle cable are connected by the two left and right first connecting bolts, so that the camshaft drive member of the carburetor device is connected. A space is formed in a portion facing the accommodating chamber, so that there is no interference between the first connecting bolt and the accommodating chamber of the cylinder head, and thus the entire carburetor device can be brought closer to the engine side, and as a result, the intake pipe length can be shortened. .

Further, although the coupling rigidity is reduced by simply dividing the connecting bolt into two, in the present invention, since the carburetor single bodies on both sides are fixed by the cable guides located in the divided portion,
It is possible to prevent a decrease in joint rigidity. Since a cable guide, which has been indispensable in the past, is used as this coupling bracket, no separate coupling component is required.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 to 6 are views for explaining a continuous vaporizer device according to an embodiment of the present invention.

In the figure, reference numeral 1 is a center drive type parallel four-cylinder engine equipped with the device of the present embodiment. The engine 1 has a cylinder block 4, a cylinder head 5, and a head cover 6 on a crankcase 3 having an oil pan 2 on the bottom surface. Are laminated. An exhaust cam shaft 7a and an intake cam shaft 7b are arranged above the cylinder head 5 so as to extend in parallel and in the vehicle width direction. And this both camshaft 7
Cam sprockets 8a, 8b are fixed to the center of the a, 7b in the vehicle width direction, and both sprockets 8a, 8b and a sprocket of a crankshaft (not shown) are connected by a timing belt 9. The timing belt 9, the cam sprocket 8 of the cylinder head 5 and the head cover 6 are
The accommodating chambers 5a and 6a for accommodating a, 8b and the like bulge in the vehicle front-rear direction.

Intake port formed on the rear wall of the cylinder head 5
The continuous vaporizer device 10 of the present embodiment is attached to 5b.
The carburetor device 10 is formed by arranging four carburetor units 11a to 11d in parallel and connecting them to each other. Each carburetor unit 11a ~ 11d, the butterfly type throttle valve 13 is disposed on the downstream side 12a of the mixing chamber 12, the float chamber 14 is attached to the lower side, and the diaphragm chamber 15 is formed on the upper side, and the chamber 15 Jet needle down
A piston valve 16 having 16a is arranged. Further, the engaging recesses 17 are formed on the left side walls of the individual vaporizers 11a to 11d.
a has engaging protrusions 17b formed on the right side wall,
The concave and convex parts of the adjacent vaporizers are engaged with each other. Furthermore, in the mixing chamber 12, a first connecting portion 12b (engine side connecting portion) having a connecting hole is provided above the throttle valve 13, and a second connecting portion 12c having a connecting hole is provided at a lower portion of the upstream side 12d. (Anti-engine side connection part) is formed, respectively.

And each said vaporizer simple substance 11a-11d is the 2nd connection part 12c.
Are connected and fixed by one second connecting bolt 18 and a nut 18a. Further, the left carburetor single body 11a, 11b and the right carburetor single body 11c, 11d respectively have a first connecting portion 12b part divided into two left and right first connecting bolts 19a, 19b and a nut. It is fixed by 19c. As a result, the connecting bolt is interrupted at the central portion of the engine-side connecting portion to provide a space.

A throttle cable 20 is connected between the carburetor units 11b and 11c, that is, at the center of the continuous carburetor device 10. The cable 20 is connected to a valve arm 22 through a guide portion formed at a rear end portion 21a of a cable guide 21 arranged at the central portion, the arm 22 being the central carburetor unit 11b, A link mechanism 2 having an interference spring at the center side end of the rotating shaft 13a of the 11 c
It is connected via 3a. The outer ends of the rotary shafts 13a are connected to the rotary shafts 13a of the carburetor units 11a and 11d located outside the rotary shafts 13a through a link mechanism 23b having an interference spring. The rear end 21a and the front end 21b of the cable guide 21 are fixed to the carburetor unit 11c on the right side of the center with a fixing bolt 24.
The fixed flange portion 21c, which is fixed by a and 24b and extends forward from the front end portion 21b, has the tip of the left first connecting bolt 19a inserted therein and is fixed by a nut 19c.

Reference numeral 25 is a choke lever, and the choke mechanism is operated by moving the bracket 26 left and right.

And the mixing chamber of each vaporizer unit 11a-11d
A downstream side 12a of 12 is connected to an intake port of the cylinder bed 6 via an intake pipe 24. In this case, the left and right first connecting bolts 19a, 19b of this embodiment are the cylinder head 6,
The head cover 6 is located closer to the engine than the rear edges of the accommodating chambers 5a, 6a, and the rear edges are the central carburetor unit 11b,
It is located between 11c (see Fig. 5).

As described above, in the continuous carburetor 10 of this embodiment, the first connecting bolt on the engine side is divided into the left and right connecting bolts 19a and 19b, and the left carburetor units 11a and 11b are connected to the left first connecting bolt. Since the carburetor single bodies 11c and 11d on the right side are connected to each other by the right first connecting bolt 19b with the bolt 19a, a space is formed in the central portion, and the rear edge portions of the chain accommodating chambers 5a and 6a are located in the space portion. Therefore, it is possible to solve the conventional problem that the connecting bolt and the chain accommodating chamber interfere with each other, and bring the continuous carburetor device 10 close to the cylinder head 5 of the engine 1, thereby reducing the length of the intake pipe 24. It can be shortened, and as a result, it is possible to meet the demand for a high rotation type engine.

On the other hand, if the connecting bolt is simply divided into two parts, the coupling rigidity of the carburetor device 10 may decrease. However, in the present embodiment, the lower parts (anti-engine side) of all the carburetors 11a to 11d should be placed in the first part. Connected with 2 connecting bolts 18 and left carburetor unit 11a,
Upper part of 11b (engine side), right carburetor unit 11c, 11d
The upper parts of the two are connected by the left and right first connecting bolts 19a, 19b, and the left and right connected bodies are connected by the cable guide 21, so that the valve shaft 13 is substantially opposed to each other as in the conventional case. Since the positions to be joined are joined, sufficient joining rigidity can be secured. Further, in this case, since the cable guide 21 which is indispensable for this type of carburetor device is also used as the coupling bracket, a new component is not required for the above coupling.

Although the cable guide is a separate component in the above embodiment, this cable guide may be integrated with, for example, the vaporizer unit 11c in the present invention.

Further, although the four-cylinder engine has been described in the above-mentioned embodiment, the present invention is not limited to the four-cylinder engine.
As long as the cable guide is mounted so as to face the accommodation chamber, it can be applied to any case.

〔The invention's effect〕

As described above, according to the continuously mounted carburetor device according to the present invention, the bolt for connecting the engine side portion of the carburetor unit to
Since the structure is divided, the connecting bolt and the cylinder head,
There is an effect that the problem of interference with the head cover can be solved and the carburetor device can be brought closer to the engine, and as a result, the intake pipe length can be shortened to cope with a high rotation engine,
Further, since the central carburetors are connected to each other by using the cable guide, there is an effect that the connecting rigidity between the individual carburetors can be secured without increasing the number of parts.

[Brief description of drawings]

1 to 5 are views for explaining a continuous carburetor device according to an embodiment of the present invention. FIG. 1 is a sectional side view showing the mounted state, and FIG. 2 is a carburetor single unit. A sectional side view, FIG. 3 is a front view thereof, FIG. 4 is a rear view thereof, FIG. 5 is a plan view of the mounted state, and FIG. 6 is a side view of an engine to which the carburetor device is mounted. In the figure, 1 is an engine, 9 is a cam chain (cam shaft driving member), 10 is a continuous carburetor device, 11a to 11d are carburetor units, 11b and 11c are carburetor units which face each other with a cable guide, and 12b are An engine side connecting portion, 12c is an anti-engine side connecting portion, 18 is a second connecting bolt, 19a and 19b are left and right first connecting bolts, 20 is a throttle cable, and 21 is a cable guide.

Claims (1)

(57) [Claims] 1. A plurality of carburetor units are connected in parallel, and a throttle cable is disposed between any of the carburetor units, and a camshaft drive member accommodating chamber is formed between the cylinders. In a continuous carburetor device mounted on a multi-cylinder engine so that the throttle cable faces the drive member accommodating chamber, the engine side connecting parts of the carburetor unit located on the left side or the right side of the throttle cable are connected to each other. The left and right first connecting bolts, which are divided into two parts, are connected and fixed to each other, and the anti-engine side connecting portions of all the carburetors are connected and fixed to each other with one second connecting bolt, and the throttle cable is connected to the throttle valve. A multi-cylinder engine coupling type in which carburetor units facing each other with the guide interposed therebetween are fixed by a cable guide that guides the drive arm. Encoder apparatus.