JPH07293329A - Oil pan device for internal combustion engine - Google Patents

Abstract

(57) [Summary] [Purpose] While reducing the sound emitted from the oil pan,
By simply controlling the position of the inner pan, displacement of the inner pan during operation is prevented and workability during assembly is improved. [Structure] An inner pan 19 having a substantially similar shape is settled in the oil pan 18 in a non-fixed state, and lubricating oil penetrates into gaps 22 and 23 between the two to form a thin oil layer. Further, the lower end surface of the partition wall portion 17 has the oil pan rail 1
By being located above the lower end surface of 6, the step portion 26 is integrally formed inside the oil pan rail 16. Therefore, the position of the inner pan 19 is
It is regulated by the horizontal surface 26A and the vertical surface 26B. Further, when the cylinder block 11 is assembled upside down, the position of the inner pan 19 is determined by the step 26, so that the oil pan 18 can be easily attached.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil pan device attached to a lower surface of a cylinder block of an internal combustion engine, and more particularly to an improvement of an oil pan device in which an inner pan is settled in oil of an oil pan in a non-fixed state. .

[0002]

2. Description of the Related Art In many internal combustion engines represented by automobile internal combustion engines, a relatively deep oil pan is provided on the lower surface of a cylinder block, and lubricating oil stored in this oil pan is sucked up by an oil pump and pumped to various parts. It has become.

An oil pan according to the prior art will be described with reference to FIG.

FIG. 7 is a sectional view showing a state in which the oil pan 100 is attached. The oil pan 100 is formed by press-molding a thin steel plate. For example, a portion near the front end of the engine has a bottom (not shown). The deep bottom portion is in the shape of a rectangular tube, and the remaining portion is the shallow bottom portion 101 in the shape of a tray. The side wall of the oil pan 100 is formed substantially vertically, and the flange portion 102 is integrally provided at the upper end edge of the side wall.

A bearing cap 112 for pivotally supporting a crankshaft 111 is provided on the lower surface of a cylinder block 110 having a plurality of cylinders such as four cylinders and six cylinders.
Are attached via a plurality of bolts 113. Further, a skirt portion 114 extending to the outside of the bearing cap 112 is integrally formed on the lower surface of the cylinder block 110, and an oil pan rail 115 for mounting the oil pan 100 is integrally formed on the lower surface of the skirt portion 114. It is provided.

[0006] Such an oil pan 10 according to the prior art.
At 0, when the engine starts and the oil pump operates, the lubricating oil in the deep bottom part is sucked up by the oil pump,
It is fed by pressure to each part of the engine through a main gallery or the like.
Then, the lubricating oil that has lubricated and cooled each part of the engine is discharged from an oil return hole or the like on the upper surface of the crankcase, and flows down into the oil pan 100 via the inner wall surface of the crankcase and the oil passage.

By the way, since the oil pan 100 is formed by press-forming a steel plate, there is a problem that the vibration of the engine causes the film to vibrate and a relatively large radiated sound is generated.

In view of such a problem, therefore, the oil pan is formed in a double structure from the outer plate and the inner plate, and the outer plate and the inner plate are connected to each other through a large number of small holes formed in the inner plate. Another conventional technique in which the gap is filled with lubricating oil is disclosed in, for example, Japanese Utility Model Laid-Open No. 54-259
No. 41 publication and the like. In this type of conventional technique, the lubricating oil in the gap flows through the small holes of the inner plate as the film of the oil pan vibrates, so that the vibration can be attenuated by the loss during the circulation.

However, in such another conventional technique, the inner plate is fixed to the outer plate, and there is a limit in working accuracy and welding accuracy. Therefore, a gap between the outer plate and the inner plate, that is, an oil layer is formed. Even if it is attempted to make it thin, it naturally has its limits. Moreover, since the inner plate and the outer plate are fixed to each other, it is not possible to exert a pressing action on the oil layer by the weight of the lubricating oil and the weight of the inner plate itself. Therefore, the energy damping effect due to the flow of the lubricating oil cannot be increased, so that the noise reduction effect obtained is smaller than the increase in weight due to the addition of the inner plate. Further, since the inner plate having a large number of small holes is fixed to the outer plate with a slight gap, the structure is complicated and the manufacturing cost is increased.

Therefore, as shown in FIG. 8, the present applicant disposes the inner pan 2 having a wall surface having a shape along the inner wall surface of the oil pan 1 in the lubricating oil of the oil pan 1 in a non-fixed state. An oil pan damping structure as an oil pan device has been previously proposed in which a thin oil layer is defined between the oil pan 1 and the inner pan 2.

In general, referring to FIG. 8, an oil pan 1 formed by press-forming a steel plate has a deep bottom portion 1A in the shape of a square cylinder with a bottom at the front end of the engine, and a shallow bottom portion 1B in the shape of a tray. Has become. The side wall of the oil pan 1 extends substantially vertically, and a flange portion 1C attached to an oil pan rail (not shown) of the cylinder block is integrally provided at the upper end of the side wall.

Inner pan 2 formed by press forming a steel plate
Similarly to the oil pan 1 described above, the oil pan 1 also has a deep bottom portion 2A and a shallow bottom portion 2B, and is formed to have a shape along the inner wall surface of the oil pan 1 as a whole. That is, the inner pan 2 is substantially smaller than the oil pan 1 so that a slight gap 3 is defined between the outer wall surface of the inner pan 2 and the inner wall surface of the oil pan 1 when the inner pan 2 is settled in the oil pan 1. It is formed in a similar shape. Further, since the radiated sound is mainly generated in the tray-shaped shallow bottom portions 1B, 2B, the deep bottom portion 2A of the inner pan 2 extends to a depth approximately in the middle of the deep bottom portion 1A of the oil pan 1, and the bottom surface thereof has an oil drain port. 4 is formed. In addition, 5 shown in the figure is
It is a drain cock.

According to the technique previously proposed by the applicant, the inner pan 2 is set in the lubricating oil in a non-fixed state with respect to the oil pan 1, so that a thin oil layer is formed at least on the bottom wall side thereof. Is made. Therefore, when the vibration input of the engine is applied to the oil pan 1 and the film vibration occurs, the lubricating oil in the gap 3 tries to flow along two surfaces of the bottom wall surface of the inner pan 2 and the bottom wall surface of the oil pan 1. To do. For this reason,
The vibration energy is converted into the kinetic energy of the lubricating oil, and this kinetic energy is attenuated by the friction with each wall surface and the friction between the oils.

[0014]

According to the technique previously proposed by the present applicant, since the inner pan 2 is set in a non-fixed state, the oil layer between the oil pan 1 and the inner pan 2 can be formed as much as possible. It can be thinly defined, and radiated sound can be significantly reduced. However, since the oil pan 1 and the inner pan 2 are formed separately from each other and both are in a non-fixed state, if the inner pan 2 is displaced during manufacturing,
The oil pan 1 cannot be easily attached, which may reduce the workability of the assembly work.

That is, in general, the oil pan 1 is attached to a cylinder block by inverting the cylinder block and arranging it upside down, and arranging the lower surface on which the oil rails are formed upward, and then the cylinder. This is performed by placing the oil pan 1 on the lower surface of the block from above and fixing the oil pan 1 via bolts. Therefore, when an oil pan device that disposes the inner pan 2 on the oil pan 1 in a non-fixed state is attached by this manufacturing method,
First, it is necessary to mount the inner pan 2 on the lower surface of the cylinder block arranged upside down, and then attach the oil pan 1 so as to cover the inner pan 2. However, if the position of the inner pan 2 placed first is displaced, it takes time and effort to attach the oil pan 1 from the outside of the inner pan 2, and the workability may be reduced.

Therefore, the main object of the present invention is to reduce the radiated sound to enhance the sound vibration characteristics, and to position the inner pan easily by providing the step portion corresponding to the inner pan on the lower surface of the cylinder block. An object of the present invention is to provide an oil pan device for an internal combustion engine that is made possible. Another object of the present invention is to prevent the inner pan from interfering with a rotary moving body such as a crankshaft even when the inner pan rises. A further object of the present invention is to improve the work efficiency of the assembling work by positioning and mounting the inner pan on the cylinder block.

[0017]

Therefore, the structure adopted by the oil pan device for an internal combustion engine according to the present invention is mounted on the lower surface of the cylinder block of the engine body via the oil pan rail to store the lubricating oil inside. An oil pan device for an internal combustion engine including an oil pan and an inner pan that has a wall surface shaped along the inner wall surface of the oil pan and is settled in the oil of the oil pan in a non-fixed state via a thin oil layer A step portion located inside the oil pan rail is provided on the lower surface of the cylinder block.

Further, a separation dimension between the inner pan and the step portion is set so that the inner pan is separated from the motion region of the rotary moving body rotated by the engine body when the inner pan is in contact with the step portion. Preferably.

Further, when the cylinder block is inverted and the inner pan and the oil pan are mounted, the inner pan is positioned inside the oil pan mounting position when the inner pan is in contact with the step portion.
Setting the distance between the inner pan and the step is
More preferable.

Further, it is preferable that the side wall of the inner pan extends above the side wall of the oil pan.

Further, the step portion may be formed in a groove shape.

[0022]

A part of the lubricating oil that has flowed back into the oil pan enters between the inner pan and the oil pan, whereby the outer wall surface of the inner pan and the inner wall surface of the oil pan come close to each other through a thin oil layer. In this state, when the oil pan vibrates,
The lubricating oil tries to flow along the wall surface in the thin oil layer with a slight change in the gap between the two, so that an energy damping action occurs, and this energy damping action suppresses the film vibration of the oil pan, and the radiated sound is emitted. Reduce. In particular, since the inner pan is settled in a non-fixed state, the weight of the lubricating oil dropped in the inner pan is added to the weight of the inner pan, and the oil layer can be further thinned.

On the other hand, if the step portion located inside the oil pan rail is provided on the lower surface of the cylinder block, the displacement of the inner pan can be restricted by the step portion even when the inner pan is lifted up by a shock during traveling. it can.

Further, when the inner pan is in contact with the step portion, the separation dimension between the inner pan and the step portion is set so that the inner pan is separated from the movement region of the rotary moving body rotated by the engine body. For example, it is possible to prevent the inner pan that has been lifted up due to a shock or the like from interfering with the rotating body.

Further, when the cylinder block is inverted and the inner pan and the oil pan are attached, the inner pan and the inner pan are positioned so that the inner pan is positioned inside the oil pan attachment position when the inner pan is in contact with the step. By setting the separation distance between the step and the stepped part, it is possible to prevent the inner pan from coming into contact with the oil pan when the oil pan is mounted so as to cover the inner pan, and the oil pan can be easily attached to the cylinder. Can be attached to the block.

If the side wall of the inner pan extends above the side wall of the oil pan, the oil level of the oil layer formed between the side wall of the inner pan and the side wall of the oil pan can be increased.

Further, even if the step portion is formed in a groove shape, the position of the inner pan can be regulated by the groove step portion.

[0028]

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

First, FIG. 1 is a sectional view showing the overall construction of an oil pan device for an internal combustion engine according to a first embodiment of the present invention. For example, an engine body having a plurality of cylinders such as four cylinders and six cylinders. A bearing cap 13 for pivotally supporting the crankshaft 12 is attached to the lower surface of the cylinder block 11 via a plurality of bolts 14. Also,
On the lower surface of the cylinder block 11, a deep skirt-shaped skirt portion 1 extending outside the bearing cap 13 is provided.
5 is integrally formed, and an oil pan rail 16 is provided on the lower surface of the skirt portion 15. Furthermore, FIG.
As also shown in the drawing, a partition wall portion 17 is integrally provided on the inner surface side of the skirt portion 15 corresponding to each bearing cap 13 (so as to partition the cylinders from each other).

On the oil pan rail 16 of the cylinder block 11, an oil pan 18 formed by press forming a steel plate is liquid-tightly mounted via gaskets, bolts (not shown) and the like. Similar to the oil pan 1 described above, the oil pan 18 includes a deep bottom portion 18A and a shallow bottom portion 18B as shown in FIG. 2, and a flange portion 18C is formed at the upper end edge of its substantially vertical side wall. There is.

Inside the oil pan 18, an inner pan 19 made by press forming a steel plate is settled in a non-fixed state. The inner pan 19 is configured by vertically arranging a side wall 21 from a peripheral edge of a substantially rectangular bottom wall 20,
It has a deep bottom portion 19A and a shallow bottom portion 19B, and is formed in a substantially similar shape along the inner wall surface of the oil pan 18 as a whole. Here, the inner pan 19 differs from the inner pan 2 shown in FIG. 8 in that the side wall 21 thereof extends above the side wall of the oil pan 18.

A slight gap 22 is defined between the bottom wall 20 corresponding to the shallow bottom portion 19B of the inner pan 19 and the bottom wall of the oil pan 18, and the lubricating oil flowing into the gap 22 forms a thin oil layer. Are formed. Further, another gap 23 which is slightly wider than the gap 22 is defined between the side wall 21 of the inner pan 19 and the side wall of the oil pan 18, and the lubricating oil also flows into this gap 23 to form a thin oil layer. ing.

The deep bottom portion 19A of the inner pan 19 is
It extends to a depth approximately in the middle of the deep bottom portion 18A of the oil pan 18, and has an opening 24 as an oil drain port on the bottom surface thereof.
Are formed. In addition, 25 shown in FIG. 2 is a drain cock.

The step portion 26 has a lower end surface of the partition wall portion 17 formed on the inner surface of the skirt portion 15 and the oil pan rail 16.
And the inner surface of the. Specifically, the stepped portion 26 is formed such that the lower end surface of the partition wall portion 17 is located above the lower end surface of the oil pan rail 16 by a predetermined dimension H ₁ by cutting out the lower end surface of the partition wall portion 17, for example. It is formed by a horizontal shaped surface 2 facing spaced by a predetermined distance H ₂ on the upper end surface of the side wall 21 of In'napan 19
6A (the lower end surface of the partition wall portion 17) and a vertical surface 26B (inside the oil pan rail 16) that is substantially orthogonal to the horizontal surface 26A and faces the outer surface 21A of the side wall 21 of the inner pan 19 with a predetermined distance W therebetween. Wall surface).

These step portions 26 have horizontal surfaces 26A.
The vertical position (Z direction, which is the cylinder axis direction of the cylinder block 11) of the inner pan 19 is regulated by the vertical surface 26B, and the horizontal position (X direction, which is the width direction of the cylinder block 11) of the inner pan 19 is regulated by the vertical surface 26B. It regulates. The position of the inner pan 19 in the front-rear direction (the Y direction, which is the longitudinal direction of the cylinder block 11) is restricted by the front wall 1 of the skirt portion 15 as shown in FIG.
5A and back wall 15B.

Further, here, the inner pan 19 is restricted in displacement in the vertical, horizontal, and front-back directions by the step portion 26 and the front wall 15A and the rear wall 15B of the skirt portion 15. The inner pan 19 is set so as to be separated from the motion region of the rotary motion body that is rotated by the engine body such as the crankshaft 12 and the connecting rod (not shown). Therefore, even when the inner pan 19 is displaced up and down, left and right, and back and forth due to an impact or the like, the inner pan 19 does not interfere with the rotating body.

The "rotational moving body" referred to in the present specification is a general term for a moving body that is rotated by the engine body in a space area on the oil pan 18 side including at least the crankshaft 12 and the connecting rod. Also,
The "movement region" referred to in the present specification means the locus of rotation of the rotating body.

The oil pan device for an internal combustion engine according to this embodiment has the above-mentioned structure. Next, an assembling method thereof will be described with reference to FIG.

First, in the cylinder block inversion process, as shown in FIG. 4, the cylinder block 11 on which the step portion 26 is formed is inverted and placed upside down, and the oil pan rail 16 is positioned above.

Next, in the inner pan placing step, the side wall 21
The upper end surface of the step portion 26 against the horizontal surface 26A of the step portion 26,
The inner pan 19 is placed on the inverted cylinder block 11. Here, in the state shown in FIG. 1, the lower end surface of the partition wall portion 17 is higher than the lower end surface of the oil pan rail 16 for mounting the oil pan 18, that is, the step portion 26 is higher than the oil pan rail 16. Since it is formed on the inner side, the inner pan 19 is located on the inner side of the mounting position of the oil pan 18. The position of the inner pan 19 in the left-right direction is regulated by the vertical surface 26B of the step portion 26, and the inner wall 19 of the skirt portion 15 is formed.
The position in the front-rear direction is regulated by A and the rear wall 15B. In addition, between the inner pan 19 and the step portion 26, etc.,
Since a slight margin is secured, the inner pan 19 can be easily placed in the step portion 26.

Further, in the oil pan mounting step, after covering the oil pan 18 from the upper side of the inner pan 19 positioned by the step portion 26 and bringing the flange portion 18C of the oil pan 18 into contact with the oil pan rail 16,
The cylinder block 11 is fixed by bolts so that the cylinder block 11 is erected to the original state.

The oil pan device for an internal combustion engine according to the present embodiment is assembled in this way.
Since the inner pan 19 is settled in the inside in a non-fixed state, a gap 2 between the oil pan 18 and the inner pan 19 is formed.
A thin film-like oil layer is defined at 2 and 23, respectively. Therefore, as shown in the characteristic diagram of FIG. 5, when the shallow bottom portion 18B of the oil pan 18 causes film vibration, the lubricating oil flows in the oil layer,
Radiated sound is greatly reduced by the energy conversion by this flow.

On the other hand, when the inner pan 19 is displaced upward, leftward and rightward, and frontward and rearward due to road surface conditions, sudden stop, etc., the inner pan 19 abuts on the stepped portion 26 and the like, so that the positional deviation is restricted, and the inner pan 19 and the connecting rod etc. are restricted. Interference with is prevented beforehand. More specifically, when the inner pan 19 is displaced upward by a predetermined dimension H ₂ , the upper end surface of the side wall 21 comes into contact with the horizontal surface 26A of the step portion 26, so that the upward displacement is restricted. Further, when the inner pan 19 is displaced in the left-right direction by the predetermined dimension W, the outer surface 21A of the side wall 21 comes into contact with the vertical surface 26B of the step portion 26.
The lateral displacement is restricted. Further, when the inner pan 19 is displaced in the front-rear direction, the outer surface 21A of the side wall 21 comes into contact with the front wall 15A or the rear wall 15B of the skirt portion 15,
The displacement in the front-back direction is restricted.

Therefore, according to this embodiment, the following effects can be obtained.

First, since the inner pan 19 formed in a substantially similar shape is settled in the oil pan 18 through a thin oil layer and arranged in a non-fixed state, as described above, lubrication for flowing the oil layer is performed. Oil can significantly reduce the radiated sound.

Secondly, on the lower surface of the cylinder block 11,
Since the stepped portion 26 located inside the oil pan rail 16 is provided, even when the inner pan 19 is displaced,
The inner pan 19 can be brought into contact with the stepped portion to regulate the positional deviation.

Thirdly, when the cylinder block 11 is inverted and the inner pan 19 and the oil pan 18 are attached,
When the inner pan 19 is in contact with the step 26,
Since the separation dimension between the inner pan 19 and the step portion 26 is set so that the inner pan 19 is located inside the mounting position of the oil pan 18, the inner pan 19 can be positioned by the step portion 26. The oil pan 18 can be mounted on top of the cover 19. As a result, it is possible to prevent the inner pan 19 from interfering with the oil pan 18 when it is attached, and the working efficiency of the assembling work can be significantly improved.

Fourth, the inner pan 1 generated during engine operation
Since the stepped portion 26 that regulates the displacement of 9 within the range where it does not interfere with the rotating body is also used as the positioning member when the inner pan 19 is mounted, the stopper member and the positioning member can be integrated, and the structure is simple. Despite this, reliability and workability can be improved.

Fifth, since the side wall 21 of the inner pan 19 is extended above the side wall of the oil pan 18,
As shown in FIG. 2, rather than the one previously proposed by the applicant,
The gap 23 can be formed high by the dimension δ, the oil layer between the side wall 21 of the inner pan 19 and the side wall of the oil pan 18 can be secured at a high position, and the radiated sound can be more effectively reduced. Further, as a result of extending the side wall 21 of the inner pan 19, the portion of the side wall 21 exposed to the outside of the lubricating oil increases, and the lubricating oil scraped up by the crankshaft 12 effectively adheres to this exposed surface. It is also possible to reduce the consumption of lubricating oil.

Sixth, because the step portion 26 is formed by locating the lower end surface of the partition wall portion 17 above the lower end surface of the oil pan rail 16 by a predetermined dimension H ₁ .
The overall structure can be simplified, and the work efficiency of the assembling work can be improved without increasing the cost.

Seventh, the inner pan 19 is replaced with the oil pan 18
Since it is a configuration in which it is settled only in the shallow bottom portion 18B, not in the whole, the radiation sound from the shallow bottom portion 18B, which is the main cause of the radiation sound, can be effectively reduced, and the weight and manufacturing cost of the inner pan 19 can be reduced.

When the structure of the step portion 26 and the like is limited in more detail, the present embodiment can be understood as follows. That is, an oil pan 18 that is mounted on an oil pan rail 16 formed on the lower surface of the deep skirt portion 15 of the cylinder block 11 and stores lubricating oil inside, and a wall surface having a shape along the inner wall surface of the oil pan 18 are provided. Have,
An oil pan apparatus for an internal combustion engine, comprising: an inner pan 19 which is settled in the oil of an oil pan 18 in a non-fixed state via a thin oil layer, wherein a partition wall portion 17 is provided on a lower end surface of the cylinder block 11. The lower end surface of the oil pan rail 1
By being positioned above the lower end surface of 6 by a predetermined dimension H ₁ , the horizontal surface 26A corresponding to the upper end surface of the side wall 21 of the inner pan 19 and the outer surface 2 of the side wall 21 of the inner pan 19 are positioned.
Step portion 2 having a vertical surface 26B corresponding to 1A
6 is provided integrally inside the oil pan rail 16 and is configured to allow the inner pan 19 to be displaced by the step portion 26 to the extent that it does not interfere with the rotary moving body rotated by the engine body. An oil pan device for an internal combustion engine.

The assembly of the oil pan device described above can be understood as follows. That is, an oil pan 18 that is mounted on an oil pan rail 16 formed on the lower surface of the deep skirt portion 15 of the cylinder block 11 and stores lubricating oil inside, and a wall surface having a shape along the inner wall surface of the oil pan 18 are provided. And an inner pan 19 that is settled in the oil of the oil pan 18 in a non-fixed state via a thin oil layer, and has a lower end surface of the partition wall portion 17 with a predetermined dimension H than the lower end surface of the oil pan rail 16. ₁
By arranging it only above, the horizontal surface 26A corresponding to the upper end surface of the side wall 21 of the inner pan 19 and the vertical surface 26B corresponding to the outer surface 21A of the side wall 21 of the inner pan 19.
A method of assembling an oil pan device for an internal combustion engine, wherein a stepped portion 26 having an inner side of an oil pan rail 16 is provided inside the oil pan rail 16, and a step of inversion of the cylinder block 11 and an inner pan 19 A step of placing the inner pan 19 on the inverted cylinder block 11 by bringing the upper end surface of the side wall 21 into contact with the horizontal surface 26A of the step portion 26, and an oil pan from above the placed inner pan 19 Cover with 18 and oil pan rail 16
And a method for assembling an oil pan device for an internal combustion engine, the method comprising:

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the same components as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted. Here, the feature of this embodiment resides in that the step portion is formed in a groove shape.

FIG. 6 is a sectional view showing the structure of the oil pan device according to this embodiment. In this embodiment, the outer peripheral edge of the oil pan rail 31 projects outward from the outer surface of the skirt portion 15 by a predetermined dimension D. Is formed.

The oil pan 32 has a shallow bottom portion 32A and a deep bottom portion (not shown), like the oil pan 18 described in the first embodiment, and is attached to the oil pan rail 31 at the upper end of the side wall thereof. A flange portion 32B is formed. Further, the width dimension of the oil pan 32 becomes longer as the formation position of the oil pan rail 31 expands to the outside.

In the inner pan 33 according to this embodiment, like the inner pan 19 described in the first embodiment, a side wall 35 is provided upright around the bottom wall 34, and a shallow bottom portion 33A and a deep bottom portion (not shown) are provided. And is settled in the oil pan 32 in a non-fixed state. The inner pan 33 is also formed to have a large width dimension corresponding to the oil pan rail 31, and the side wall 35 thereof is located slightly below the side wall of the oil pan 32.

A step portion 36 is integrally formed on the lower end surface of the skirt portion 15 inside the oil pan rail 31. This step portion 36 is formed by the inner pan 33.
A horizontally surface 36A opposed spaced by a predetermined distance H ₃ from the upper end surface of the side wall 35, an outer vertical shaped surface 36B which faces away from the outer surface 35A of the side wall 35 by a predetermined distance W _1,
From the inner vertical shape surface 36C that faces away from the inner surface 35B of the side wall 35 by a predetermined distance W _2, it is formed as a substantially downwardly U-shaped groove.

In this embodiment having such a configuration, the same operation and effect as those described in the first embodiment can be obtained. Particularly, in the present embodiment, the formation position of the oil pan rail 31 is shifted to the outside and the groove-like step portion 36 is formed inside the oil pan rail 31, so that the rotational movement of the crankshaft 12, the connecting rod, or the like is performed. Even when the clearance between the body motion area and the side wall of the cylinder block 11 is small, the inner pan 33
Position regulation can be performed.

[0060]

As described in detail above, according to the oil pan device for an internal combustion engine of the present invention, since the inner pan is settled in the oil pan in a non-fixed state, a thin oil layer is formed between the inner pan and the oil pan. Radiation noise can be reduced by the lubricating oil that can be formed and flows in this oil layer.

On the other hand, if the step portion located inside the oil pan rail is provided on the lower surface of the cylinder block, the displacement of the inner pan can be regulated by the step portion even when the inner pan is lifted up by a shock during traveling. it can.

Further, when the inner pan is in contact with the step portion, the separation dimension between the inner pan and the step portion is set so that the inner pan is separated from the motion area of the rotary moving body rotated by the engine body. For example, it is possible to prevent the inner pan that has been lifted up due to a shock or the like from interfering with the rotating body.

Further, when the cylinder block is inverted and the inner pan and the oil pan are attached, the inner pan and the inner pan are positioned so that the inner pan is located inside the oil pan attachment position when the inner pan is in contact with the step portion. By setting the separation distance between the step and the stepped part, it is possible to prevent the inner pan from coming into contact with the oil pan when the oil pan is mounted so as to cover the inner pan, and the oil pan can be easily attached to the cylinder. Can be attached to the block.

If the side wall of the inner pan extends above the side wall of the oil pan, the oil level of the oil layer formed between the side wall of the inner pan and the side wall of the oil pan can be increased.

Further, even if the step portion is formed in a groove shape, the position of the inner pan can be regulated by the groove step portion.

[Brief description of drawings]

FIG. 1 is a partially broken explanatory view showing an overall configuration of an oil pan device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing an arrangement relationship between an oil pan and an inner pan.

FIG. 3 is a bottom view of a cylinder block.

FIG. 4 is a partially broken explanatory view showing a state in which an oil pan or the like is attached to an inverted cylinder block.

FIG. 5 is a characteristic diagram for explaining a radiated sound reducing effect of an oil layer.

FIG. 6 is a partially broken explanatory view showing the overall configuration of an oil pan device according to a second embodiment of the present invention.

FIG. 7 is an explanatory view of an oil pan according to a conventional technique.

FIG. 8 is a sectional view of the oil pan device previously proposed by the applicant.

[Explanation of symbols]

 11 ... Cylinder block 12 ... Crank shaft (rotating body) 16, 31 ... Oil pan rail 18, 32 ... Oil pan 19, 33 ... Inner pan 21, 35 ... Side wall 26, 36 ... Step portion

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location F16N 35/00

Claims (5)

[Claims] 1. An oil pan, which is mounted on the lower surface of a cylinder block of an engine body via an oil pan rail, has an oil pan for storing lubricating oil therein, and a wall surface shaped along the inner wall surface of the oil pan. An oil pan device for an internal combustion engine comprising: an inner pan that is settled in oil in a non-fixed state via a thin oil layer, wherein a step portion located inside an oil pan rail is provided on a lower surface of the cylinder block. An oil pan device for an internal combustion engine, comprising: 2. A separation dimension between the inner pan and the step portion is set so that the inner pan is separated from a motion region of a rotary moving body rotated by the engine body when the inner pan is in contact with the step portion. The oil pan device for an internal combustion engine according to claim 1, wherein: 3. When the cylinder block is inverted and the inner pan and the oil pan are attached, the inner pan is positioned inside the oil pan attachment position when the inner pan is in contact with the step portion. The oil pan device for an internal combustion engine according to claim 2, wherein a separation dimension between the inner pan and the step portion is set. 4. The oil pan device for an internal combustion engine according to claim 2, wherein the side wall of the inner pan extends above the side wall of the oil pan. 5. The oil pan device for an internal combustion engine according to claim 1, wherein the stepped portion is formed in a groove shape.