JPH0329580Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) This invention relates to an intake passage mounting structure for a so-called slant-type engine which is installed at an angle in order to lower the engine height in terms of vehicle body structure.

(Prior art) Generally, in order to improve the atomization of the air-fuel mixture supplied from the carburetor, a so-called intake air heating cooling water passage is installed near the intake passage of the intake manifold to drain high temperature cooling water from the water jacket of the engine body. There is an extension that guides you. That is, this cooling water passage for heating the intake air communicates with the water jacket of the engine body through a through hole in the joint surface of the intake manifold and the cylinder head, which is provided adjacent to the hole of the intake passage.

However, as shown in Fig. 1, so-called slant-type engines (for example,
No. 55-106323), when the intake manifold is removed by lifting it in a substantially vertical direction from the cylinder head after its mounting bolts are removed during engine repair, etc., water in the intake air heating cooling channel inevitably leaks. This tends to cause the inconvenience that the fuel flows into the intake passage of the adjacent engine body.

(Purpose of the invention) In order to eliminate the above-mentioned disadvantages, this invention is designed to prevent the cooling water in the intake air heating cooling channel from flowing into the intake passage of the engine body when the intake manifold is removed from the cylinder head. This is the purpose.

(Structure of the invention) This invention to achieve the above object is such that the cylinder axis is installed so as to be inclined with respect to the vertical direction of the vehicle body, and the intake manifold is located on the opposite side of the inclination.
The joint surface is arranged so as to be inclined in the direction in which the cylinder axis is tilted, and the joint surface extends from the water jacket of the engine body through the joint surface between the cylinder head and the intake manifold, and further along the lower surface of the intake passage of the intake manifold. In an engine equipped with an extended intake air heating cooling water passage, the bolt holes of the mounting bolts for attaching the intake manifold to the engine body communicate with the outside of the engine and the intake air heating cooling water passage, and the bolt holes are connected to the outside of the engine. The opening is provided so as to be located below a part of the intake air heating cooling water passage in the intake manifold.

(Embodiment) FIGS. 1 to 3 show a first embodiment of this invention, in which 1 is a carburetor, 2 is an intake manifold, 3 is a cylinder head, and 4 is a cylinder block. This engine is installed with the cylinder axis A-A sufficiently inclined with respect to the vertical direction B-B of the vehicle body.

The intake manifold 2 is fastened by a plurality of mounting bolts 6 at a flange 5 to a joint surface 9 of the cylinder head 3 that is inclined in the direction of inclination of the cylinder axis (A-A line). aisle 7
The intake manifold 2 and the intake passage 8 of the cylinder head 3 communicate with each other at a joint surface 9 between the intake manifold 2 and the cylinder head 3, with their holes abutting each other.

In addition, the engine body, that is, the cylinder head 3 and the cylinder block 4, each have a water jacket 10 for passing cooling water to prevent overheating during operation.
a, 10b are provided in communication with each other, and from the water jacket 10b, a cooling water channel 12 for heating intake air is extended so as to pass through the joint surface 9 through a through hole 11 and further closely follow the lower surface of the intake passage 7. has been done.

Reference numeral 13 denotes a mounting bolt that also serves as a water drain, and is located at the lowest of the plurality of mounting bolts 6 of the intake manifold 2, and the top surface of the flange 5 of the bolt hole 14 is at the same height as the bottom of the cooling water channel 12 for heating the intake air. is located below that. As shown in FIG. 3, the bolt hole 14 is opened so as to communicate the water jacket 10b of the cylinder head 3 with the outside of the engine. 15 is a guide wall, 16 is a bolt seal, 17 is a gasket,
18 is an intake valve.

Therefore, when removing the intake manifold 2 from the cylinder head 3 during engine repair, first remove the water draining mounting bolt 13. Since the height of the water head in the intake air heating cooling channel 12 is higher than the upper surface of the flange 5 of the bolt hole 14, All the cooling water in the water channel 12 passes through the through hole 11 and once descends into the water jacket 10b, and then flows into the water jacket 1.
0b and flows out of the engine via the bolt hole 14. As a result, the inside of the water channel 12 becomes completely empty. After removing all other mounting bolts 6,
Even if the intake manifold 2 is removed from the cylinder head 3, the water in the intake air heating cooling water passage 12 will never flow into the intake passage 8 of the cylinder head 3, unlike in the conventional case. When the cooling water overflows from the bolt hole 14 to the outside of the engine, it flows along the guide wall 15 as shown by arrow C in FIG. It's getting old.

FIG. 4 shows a second embodiment of this invention, showing the joint surface 9 between the intake manifold 2 and the cylinder head 3a.
The part shown is enlarged. Similar to the first embodiment, an enlarged portion 19 extending downward from the flange 5 of the first embodiment is formed on the flange 5a on which the drain-draining mounting bolt 13 located at the lowest level is screwed, and corresponds to the enlarged portion 19. and a flange portion 20 for screwing the tip of the water drain mounting bolt 13 onto the cylinder head 3a.
form. A gap 21 communicating with the water jacket 10b is provided at the threaded portion of the flange portion 20 where the draining and mounting bolt 13 is threaded. In other parts, intake passages 7 and 8 are formed as in the first embodiment, along with intake air heating cooling channels 12, through holes 11, etc. are formed.

In the second embodiment, the screwing position of the mounting bolt 13' is located further downward than in the first embodiment shown in FIG. It is located at a sufficiently lower position than the

Therefore, when the mounting bolts 13' are removed before removing the intake manifold 2, all of the cooling water in the water passage 12 descends through the through holes 11, enters the water jacket 10b, passes through the cavity 21, and exits from the bolt holes 14a. It will definitely be ejected.

(Effect of the invention) When removing the intake manifold during engine repair, etc., simply by removing the mounting bolts, the cooling water in the intake air heating cooling waterway that extends to the intake manifold will flow down and drain out of the engine from the bolt holes. Therefore, even in a so-called slant-type engine installed at an incline, the conventional problem of cooling water in the water passage flowing into the intake passage of the cylinder head can be reliably prevented.

[Brief explanation of drawings]

Figure 1 shows the first embodiment of this invention.
FIG. 2 is a longitudinal sectional view showing a part of the engine cut away, FIG. 2 is a sectional view taken along the - arrow in FIG. FIG. 4 shows a second embodiment of this invention, and is an enlarged sectional view of the main parts. 2... Intake manifold, 3... Cylinder head, 4... Cylinder block, 6... Mounting bolt, 7, 8... Intake passage, 9... Joint surface, 10
a, 10b...Water jacket, 11...Through hole, 12...Cooling channel for heating intake air, 13...Draining mounting bolt, 14, 14a...Bolt hole, A-A...Cylinder axis, B-B... Vertical direction of the vehicle body.

Claims (1)

[Scope of utility model registration request] The cylinder axis is installed so that it is inclined with respect to the vertical direction of the vehicle body, and the intake manifold is installed on the opposite side with the joint surface inclined in the direction in which the cylinder axis is inclined. In an engine equipped with an intake air heating cooling waterway extending from the jacket through the joint surface of the cylinder head and the intake manifold and further along the lower surface of the intake passage of the intake manifold, mounting the intake manifold to the engine body. The bolt holes of the bolts communicate with the outside of the engine and the intake air heating cooling water passage, and the openings of the bolt holes to the outside are located below a part of the intake air heating cooling water passage in the intake manifold. An engine intake passage mounting structure characterized by being provided in.