JPH0361024B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine carburetor heating device for heating a slow fuel passage of a carburetor attached to an intake manifold with cooling water after cooling the engine body.

Conventionally, in an engine carburetor, in order to effectively expose the fuel flowing out from the slow fuel passage and to prevent icing of the slow fuel passage in humid and low temperature conditions, cooling water is used after cooling the engine body to prevent the slow fuel passage from icing. A device configured to heat the slow fuel passage is known;
An example of this is shown in the publication.

However, in this type of carburetor heating device, the cooling water passage is opened to the carburetor mounting seat in order to bring the cooling water closer to the slow fuel passage and improve its heating effect. When the carburetor is removed from the intake manifold for maintenance, for example, the head of the cooling water that has remained in areas higher than the carburetor mounting surface, such as the cylinder head, will cause the cooling water to flow out from the opening of the cooling water passage. Cooling water is pushed out onto the carburetor mounting seat,
The extruded cooling water flows into the intake passage of the intake manifold. When cooling water flows into the intake passage in this way, the engine must be disassembled in order to remove the cooling water, which is an extremely complicated operation.

On the other hand, the engine body is provided with a drain hole for draining the cooling water, so when removing the carburetor, if the cooling water is drained from the drain hole, it will flow into the cooling water intake passage as described above. This will prevent the influx of There are two methods for extracting the cooling water in this case, which will be described below.

One of them is to reduce the amount of cooling water extracted.
Cooling water is extracted to such an extent that even if the carburetor is removed, the cooling water will not flow out onto the carburetor mounting seat surface.
However, with this method, the falling water level cannot be seen from the outside and judgment must be made by intuition.
It is very difficult to judge this, and if a sufficient amount of water is not removed, there is a risk that the cooling water may flow into the intake passage. Another method is to drain the entire amount of cooling water, but in this case it takes time to remove the carburetor, making work less efficient, and requires expensive cooling when replenishing new cooling water. Requires large amounts of water.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to prevent coolant from entering the intake passage when the carburetor is removed, and to prevent wasteful discharge of coolant as much as possible. An object of the present invention is to provide a vaporizer heating device.

In order to achieve the above object, in the present invention, a carburetor is fixed to the intake manifold on the carburetor mounting seat surface of the intake manifold with a carburetor fixing bolt, and an engine body is attached to the intake manifold. In the engine carburetor heating device, in which a cooling water passage for guiding cooling water from the engine is provided so as to open with respect to the carburetor mounting seat surface, a drain hole is provided in the intake manifold, and a drain hole is an extension of the drain hole. A line is formed to reach the carburetor mounting seat through the cooling water passage, and the carburetor fixing bolt is arranged to close the drain hole based on tightening of the carburetor fixing bolt. It is set up, it is configured.

With the above configuration, the bolt for fixing the carburetor also has the function of opening and closing the drain hole, and when the bolt for fixing the carburetor is loosened to take out the carburetor, the drain hole opens and the cooling water flows out. The water level will drop to at least the drain hole below the carburetor mounting seat, which is reached by the carburetor fixing bolt. Therefore, when the carburetor is removed, it is possible to prevent the cooling water from entering the intake passage, and to prevent wasteful discharge of the cooling water as much as possible.

Moreover, in this case, the discharge of the cooling water can be confirmed by stopping the flow of the cooling water. Therefore, both of the above-mentioned matters can be reliably performed.

Furthermore, since the carburetor fixing bolt opens and closes the drain hole, there is no need to prepare a special part for opening and closing the drain hole. Therefore, it is possible to reduce the number of parts.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a partially cutaway front view of an engine carburetor heating device according to an embodiment of the present invention. In this figure, 1 indicates cylinder 2 or cylinder head 3.
The engine body consists of the following parts, 4 is the piston,
5 is an intake valve, 6 is an intake port 7 of the engine body 1
The intake manifold 6 is connected to the intake manifold 6, and an upwardly facing carburetor mounting seat surface 8 is formed at the periphery of the intake port of the intake manifold 6. Reference numeral 9 denotes a carburetor, and a mounting flange 10 of this carburetor 9 is fixed to a carburetor mounting seat surface 8 of the intake manifold 6 via a gasket 11 with carburetor fixing bolts 12. The carburetor 9 is a dual type having two throttle valves 13, a primary and a secondary, but may be a single type. 14 is a slow fuel passage of the carburetor 9, and 15 is an idling adjustment screw provided at the tip of the slow fuel passage 14.

16 is an intake passage 17 connected to the intake manifold 6.
One end of this cooling water passage 16 is connected to the cooling water passage 18 of the engine body 1, and the other end is connected to the slow fuel passage 14.
An opening 19 opens to the carburetor mounting seat surface 8 of the intake manifold 6 at the lower part of the intake manifold 6 . 2
0 is a cooling water return passage connecting the opening 19 to a radiator (not shown). 21 is a counterbore for bringing the cooling water closer to the slow fuel passage 14, and is formed on the lower surface of the carburetor 9, and is connected to the gasket 1.
1 through the opening 1 of the cooling water passage 16.
It is facing 9.

A plurality of bolts 12 for fixing the carburetor are provided, and at least one of them is attached to the carburetor mounting flange 2 of the intake manifold 6 as shown in the figure.
It passes through the opening 19 of the cooling water passage 16 led into the mounting flange 22 from below 2 and is screwed onto the mounting flange 10 of the carburetor 9 . Also,
The bolt hole of the carburetor mounting flange 22 through which the carburetor fixing bolt 12 passes is a drain hole 23, and the lower part of the drain hole 23 is provided on the inner end tightening surface of the bolt head 24 and is closed by a seal washer 25. ing.

In the above configuration, the cooling water A that flows through the cooling water passage 18 on the side of the engine body 1 and cools the engine body 1 flows from this cooling water passage 18 into the cooling water passage 16 on the side of the intake manifold 6 and heats the intake passage 17. Then, after heating the slow fuel passage 14 from the counterbore 21 of the carburetor 9 at the opening 19 of the cooling water passage 16, it flows from the opening 19 through the cooling water return passage 20 to the radiator (not shown). return.

On the other hand, when the carburetor 9 is removed from the intake manifold 6, a certain amount of cooling water is necessarily extracted. To do this, first, among the carburetor fixing bolts in multiple positions, first
2 is loosened.

As a result, the drain hole 23 is opened, and the cooling water passage 18 and the cooling water return passage 20 on the side of the engine body 1 are opened.
Due to the head of the cooling water remaining at a portion higher than the bottom surface 26 of the opening 19 of the cooling water passage 16, the cooling water flows out from the drain hole 23. When the water level of the cooling water reaches the opening 19 of the cooling water passage 16
When the cooling water reaches the bottom surface 26 of the drain hole 12, the flow of cooling water from the drain hole 12 is stopped, and this stoppage indicates that the water level of the cooling water has fallen below the carburetor mounting seat surface 8. Therefore, even if all the carburetor fixing bolts 12 are removed, that is, even if the carburetor 9 is removed from the intake manifold 6,
Cooling water does not flow into the intake passage 17.

FIG. 2 shows another embodiment of the invention. In this embodiment, a part of the carburetor mounting flange 22 of the intake manifold 6, that is, a part where the opening 19 of the cooling water passage 16 is provided, is formed with an upper wall part 27 and a lower wall part 28. . The mounting flange 10 of the carburetor 9 is fixed to the upper wall portion 27 from above with a carburetor fixing bolt 12, and the bolt hole 10a of the mounting flange 10 is closed by a seal washer 29. The above carburetor fixing bolt 1
A valve body 30 is provided at the tip of 2, and this valve body 30
is press-fitted to the inner end of the drain hole 23 provided in the lower wall portion 28 to close the drain hole 23. The valve body 30 is made of an elastic material such as rubber in order to close the drain hole 23 without impairing the tightening force of the carburetor fixing bolt 12 to the carburetor 9.

In the above embodiment, the carburetor fixing bolt 12
When loosened, the cooling water flows out from the drain hole 23 and the level of the cooling water drops to the bottom surface 26 of the opening 19 of the cooling water passage 16 before the carburetor 9 is removed. Therefore, in this case as well, cooling water will not flow into the intake passage 17 due to the removal of the carburetor 9.

Components having substantially the same configuration as those in FIG. 1 are designated by the same reference numerals, and detailed explanations will be omitted.

As described above, the present invention can reliably prevent cooling water from entering the intake passage when the carburetor is removed, and can also prevent wasteful discharge of the cooling water.

Further, by using the carburetor fixing bolt, the number of parts can be reduced.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view showing one embodiment of the invention, and FIG. 2 is a partially cutaway front view showing another embodiment of the invention. 1... Engine body, 6... Intake manifold, 8... Carburetor mounting seat, 9... Carburetor, 12
...Carburetor fixing bolt, 14...Slow fuel passage, 16...Cooling water passage, 23...Drain hole.

Claims (1)

[Scope of Claims] 1. A carburetor is fixed to the intake manifold by a carburetor fixing bolt on the carburetor mounting seat surface of the intake manifold, and a cooling device for guiding cooling water from the engine body to the intake manifold. In an engine carburetor heating device in which a water passage is provided so as to open with respect to the carburetor mounting seat surface, a drain hole is provided in the intake manifold, and an extension line of the drain hole extends through the cooling water passage. and the carburetor fixing bolt is arranged to close the drain hole based on the tightening of the carburetor fixing bolt. Characteristic engine carburetor heating device.