JPS63111210A - Oil passage structure for engine - Google Patents

Abstract

PURPOSE:To enable the area of an oil return passage to be ensured without imposing a special restriction on a cylinder block by providing the oil return passage by using an intake manifold member as the structure member of an engine and a supporting stay thereof. CONSTITUTION:To a cylinder head 10 is connected an intake manifold member 18 by means of a gasket 17, and then, by using said member 18 and a supporting stay 19 is provided an oil return passage 20 interconnecting the cylinder head 10 with a crank case 8. That is, the intake manifold member 18 is provided in such a manner that the No.1-No.4 intake pipes 21-24 corresponding to each cylinder are placed, and at the same time, between the No.2 and No.3 intake pipes 22, 23 is placed the No.1 passage 25 leading into the cylinder head 10 in parallel to the intake pipes 21-24. While, on the supporting stay 19 is provided the No.2 passage 26 by way of a through hole leading from its upper end to its lower end, and then, the oil return passage 20 is composed of these No.1 and No.2 passages 25, 26.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an oil passage structure for an engine.

(Prior art) The cylinder block of an engine has a cylinder block body with a side opening in the cylinder part.

The idea of forming a so-called skeleton structure by forming a cylinder block with a panel constituting the outer wall of the cylinder block is generally known (see, for example, Japanese Utility Model Application No. 145254/1983).

Even in such a cylinder block with a skeleton structure,
An oil return passage connecting the cylinder head side and the crankcase side is required, but this oil return passage may be formed in the cylinder block body, following the example of a normal cylinder block where the cylinder part and outer wall are integrated, or The general idea is to form it by providing a separate member.

(Pressure point to be solved by the invention) However, since the oil return passage is used not only for returning oil but also as a passage for blow-by gas, it is required to have a wide passage area. In the method of forming the cylinder block on the cylinder block body, there is a problem that it is difficult to secure a wide passage area. Furthermore, the system in which the oil return passage is formed as a separate member has the disadvantage of increasing weight.

(Means for Solving the Inter-Mold Point) The present invention, as a means for solving the above-mentioned inter-mold point, attaches a panel constituting the outer wall of the cylinder block to the block body constituting the skeleton of the cylinder block, and In the structure in which the member is supported by a support stay on the skirt portion of the cylinder block, a first passage communicating with the inside of the cylinder head is formed in the intake manifold member,
A second passage passing through the support stay and communicating with the first passage into the crankcase is formed in the support stay.
The present invention provides an oil passage structure for an engine in which an oil return passage is formed by the first passage and the second passage.

(Function) In the above oil passage structure, since the oil return passage is formed using the intake manifold member, which is a component of the engine, and its support stay, the cylinder block with the skeleton structure is used to form this oil return passage. Therefore, there are no special restrictions and the weight reduction effect is not hindered. The intake manifold member and the support stay make it possible to secure an oil return passage with a relatively wide passage area, and the support stay has a closed cross-sectional structure due to the formation of the second passage, increasing its section modulus. Therefore, the support rigidity for the intake manifold member and the surge tank provided upstream thereof is improved, and vibrations thereof can be reduced. Also,
The intake manifold member itself also has a closed cross-sectional structure due to the formation of the first passage, which increases its rigidity and contributes to the vibration reduction described above.

(Effects of the Invention) Therefore, according to the present invention, the area of the oil return passage can be secured without placing any special restrictions on the cylinder block, and the support rigidity of the intake manifold can be increased to reduce vibration.

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

In the cylinder block of the engine shown in FIG.
2 is a block body, and 2 is a panel that is attached to the block body 1 via a seal member 3 and constitutes an outer wall of the cylinder block.

The block body 1 includes a cylinder portion 6.in which a cylinder 5 constituting a cylinder bore 4 is provided. Together with the oil pan 7 shown in FIG. 3, the skirt part 9 forming the crankcase 8 forms the framework of the cylinder block, and the top deck is connected to the cylinder head 10 shown in FIG. 2 via a gasket. II, a lower deck 12 at the lower end of the cylinder portion 6, and a mounting rail 13 to which the oil pan 7 is coupled. The cylinder portion 6 is formed with an opening 14 opening laterally in correspondence with the position of each cylinder 5, and the skirt portion 9 is also formed with a similar opening 15. 14 and 15 are closed by the panel 2. In this case, in the cylinder section 6, the panel 2 constitutes the outer wall of the water jacket around the cylinder 5, and the top deck 11 has cooling water passage holes 16 leading to the cylinder head 10.
is open. Further, the panel 2 is made of a plate material having a damping effect, such as a damping steel plate or a plastic plate in which a resin is sandwiched between two steel plates.

As shown in FIG. 2, an intake manifold member 18 is coupled to the cylinder head 10 via a gasket 17, and this intake manifold member 18 is attached to the support stay.
9, it is supported by the skirt portion 9 of the block body 1, as shown in FIG. An oil return passage 20 that communicates the inside of the cylinder head 10 and the inside of the crankcase 8 is formed using the intake manifold member 18 and the support stay 19.

That is, the intake manifold member 18 is formed with first to fourth intake pipes 21 to 24 corresponding to each of the four cylinders, as well as a second intake pipe 22 and a third intake pipe 2.
A first passage 25 communicating within the cylinder head 10 between the
are formed in parallel with the intake pipes 21-24. On the other hand, a second passage 26 is formed in the support stay 19 by a through hole extending from its upper end to its lower end. The second passage 26 has an upper end communicating with the first passage 25 and a lower end communicating with the inside of the crankcase 8 at the skirt portion 9 of the block body 1. A return passage 20 is configured.

Further, in FIG. 3, 27 is an oil strainer, and oil is sent from this oil strainer 27 to each part of the engine that requires lubrication, such as the valve mechanism of the cylinder head 10, via an oil pump and an oil filter. There is.

Further, each intake pipe 21 is provided in the intake manifold member 18.
A surge tank 28 connected to 24 is supported.

Therefore, in the above engine, since the cylinder block has a so-called skeleton structure, the weight of the engine can be reduced by using the thin panel 2, and by applying a damping plate to the panel 2, engine noise can be reduced. can be achieved. Thus, the first passage 25 for the oil return passage 20 is formed using the space between the second intake pipe 22 and the third intake pipe 23 of the intake manifold member 18, and the second passage is formed using the support stay 19. 26, there is no extra restriction on the cylinder block, and a relatively wide passage area can be secured while taking advantage of the above-mentioned skeleton structure. Facilitation can be achieved. Furthermore, since the oil return passage 20 communicates with the cylinder head 10 between the second and third cylinders, which is a position where oil in the cylinder head 10 is relatively easy to collect, the oil can be returned even more smoothly. will be possible.

Further, the intake manifold member 18 has a closed cross-section structure due to the formation of the first passage 25, and its rigidity is increased.
Further, the rigidity of the support stay 19 is similarly increased due to the formation of the second passage 26. Therefore, the surge tank 28 and the like on the upstream side of the intake manifold are supported by the highly rigid intake manifold member 18 and the support stay 19.
Vibration can be reduced.

In addition, in the above embodiment, the first passage was formed between the second intake pipe and the third intake pipe of the intake manifold member, but both sides of the intake manifold member &! S (outside of the first and fourth intake pipes) may be supported by support stays, and two oil return passages may be formed at both side positions of the oil return passages in accordance with the above embodiment.

Further, by connecting the engine mount member to the block body with the same bolt at the position where the support stay is connected to the block body with the bolt, the number of bolts 6 on the block body side can be reduced.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an exploded perspective view of a cylinder block, FIG. 2 is an exploded perspective view showing the relationship between the cylinder head and oil return passage components, and FIG. 3 is an exploded perspective view of the engine body. FIG. 2 is a perspective view showing a partial cross section with some parts omitted. l...Block body, 2...Panel,
6... Cylinder part, 7... Oil pan, 8... Crank case, 9... Skirt part, 10... Cylinder head, 18...
...Intake manifold member, 19...Support stay, 2o...Oil return passage, 25...
...1st aisle, 26...2nd aisle.

Claims (1)

[Claims] (1) In an engine in which a panel constituting the outer wall of the cylinder block is attached to a block body constituting the frame of the cylinder block, and an intake manifold member is supported by the skirt portion of the cylinder block via a support stay, the above-mentioned intake air A first passage communicating with the inside of the cylinder head is formed in the manifold member, a second passage communicating with the first passage and the inside of the crankcase is formed passing through the support stay, and the first passage and the second passage are formed in the support stay. An oil passage structure for an engine, characterized in that an oil return passage is constituted by the passage.