JPH10122044A - Oil pan for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress membranal vibrations of the shallow bottom of an oil pan body by improving the rigidity of the edge of the bottom thereof on the side of an opening formed therein. SOLUTION: A second bridge 13 is arranged across an opening 2c formed in an oil pan body 2 with its ends being connected to bosses 15. Three streamlining plates 5, 6 and 7 are formed on the bottom 2b of the oil pan body 2. The ends of the streamlining plates 5 to 7 on the side of the opening 2c are projected from the edge of the bottom 2b on the side of the opening 2c toward the forward end of an associated engine and are drawn upward as well so as to be coupled at their tip edges and upper edges to the vertical wall and the upper wall 13b of the second bridge 13 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an oil pan mounted on a lower surface of a cylinder block of an internal combustion engine.

[0002]

2. Description of the Related Art In many internal combustion engines typified by internal combustion engines for automobiles, an oil pan having a shallow bottom and a deep bottom is attached to the lower edge of a cylinder block. The pump sucks up the water and sends it to each part. Conventionally, an oil pan composed of an oil pan body integrally cast from an aluminum alloy or the like and a tank portion formed of a separate member fixed to one end of the oil pan body in the engine front-rear direction has been conventionally used. Are known.

The oil pan main body has a shallow bottom wall at one end in the engine front-rear direction, and a substantially rectangular opening at the bottom at the other end. The tank is generally formed by press-molding a metal plate, and is fixed to a flange formed at the lower edge of the opening of the oil pan body via mounting bolts. Lubricating oil is stored by the tank. A shallow bottom portion is formed.

[0004]

However, in the conventional oil pan in which the oil pan main body and the tank portion are formed as separate members as described above, the shallow bottom portion of the oil pan main body, that is, the opening of the bottom wall portion. Since the side edge is a free end along the opening, the rigidity is partially low. Therefore, in the bottom wall portion of the oil pan main body, a film vibration is apt to occur particularly at a portion adjacent to the opening, and there is a problem that it is a major factor of engine noise.

The main object of the present invention is to improve the rigidity of the bottom wall edge of the oil pan main body, which is a free end, thereby reducing the bottom wall membrane vibration of the oil pan main body and reducing engine noise. It is to control.

[0006]

SUMMARY OF THE INVENTION The present invention has a side wall which is bolted to the lower surface of a cylinder block of an internal combustion engine on the entire circumference, and has a shallow bottom wall at one end in the front-rear direction of the engine. And an oil pan main body integrally cast with an open bottom surface on the other end side, and a tank portion made of a metal plate mounted on the lower surface of the opening portion of the oil pan main body and storing lubricating oil. In the oil pan of the engine, a straightening plate along the engine longitudinal direction is formed integrally on the bottom surface of the bottom wall portion, and extends along the engine width direction connecting side edges along the engine longitudinal direction. A bridge portion is formed integrally with the oil pan main body, and an end of the straightening plate on the opening side and the bridge portion are coupled to each other. For example, as in claim 2, the bridge portion is disposed at a position crossing the opening, and the end of the rectifying plate on the opening side is inserted into the opening from the edge of the bottom wall on the opening side. It is configured to protrude.

That is, the current plate functions as a kind of reinforcing member to increase the rigidity of the bottom wall as a whole, and the end of the current plate located at the opening side end of the bottom wall is interposed by the bridge portion. As a result, the end of the bottom wall along the opening is firmly supported by the side edge of the oil pan main body, and the rigidity is improved.

According to a third aspect of the present invention, both ends of the bridge portion are connected to positions of through holes of mounting bolts for connecting the oil pan body and the cylinder block, respectively.

In this configuration, since both ends of the bridge portion are firmly connected to the cylinder block via the mounting bolts, the bridge portion is more securely supported by the cylinder block, and the bottom wall portion is formed. The vibration of the end is suppressed.

[0010] In particular, in claim 4, the bridge portion includes:
It is composed of a vertical wall extending in the vertical direction and an upper wall continuous with the upper end edge of the vertical wall, and has an L-shaped cross section.

With this configuration, the rigidity of the bridge itself is improved, and the rigidity of the bottom wall via the bridge is more effectively improved.

According to a fifth aspect of the present invention, the lower edge of the vertical wall of the bridge portion is set above the bottom surface of the bottom wall portion of the oil pan main body, so that the lubricating oil from the shallow bottom portion and the bridge portion are formed. Can avoid interference with the vertical wall.

According to a sixth aspect of the present invention, the end of the current plate is extended upward, and the leading edge and the upper edge of the end of the current plate are respectively formed on the vertical wall and the upper wall of the bridge portion. It is characterized by being connected.

In this configuration, since the end portion of the current plate and the bridge portion are connected along the two sides forming the L-shape, the connection between the two is further strengthened.

[0015]

According to the oil pan of the internal combustion engine according to the present invention, the opening-side end of the current plate for reinforcing the bottom wall of the oil pan main body is firmly connected to the side edge of the oil pan main body by the bridge portion. As a result, the rigidity of the bottom wall of the oil pan main body, particularly the rigidity of the portion along the opening, is greatly improved. Therefore, film vibration generated from this portion is suppressed, and engine noise is reduced.

According to the third aspect of the present invention, the bridge portion is securely supported by the cylinder block, and the rigidity of the bottom wall portion via the bridge portion is more effectively improved.

According to the fourth aspect, deformation such as bending of the bridge portion itself is suppressed, and the deformation is reduced, so that the film vibration from the shallow portion is further suppressed.

Further, according to the structure of the fifth aspect, the flow of the lubricating oil from the shallow portion of the oil pan main body to the tank portion is not obstructed.

According to the structure of claim 6, since the coupling strength between the end portion of the current plate and the bridge portion is increased, both are firmly connected. Therefore, the bottom wall is firmly supported, and the film vibration at the shallow bottom can be suppressed.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 4 show an embodiment in which the present invention is configured as an oil pan of an in-line four-cylinder internal combustion engine.
An oil pan 1 attached to a lower surface of a cylinder block (not shown), specifically, a lower edge of a skirt portion, includes an oil pan main body 2 made of aluminum die-cast, and a tank portion 3 formed by press-forming a metal plate. The oil pan main body 2 forms a flat shallow bottom portion 1a, and the tank portion 3 forms a deep bottom portion 1b in which lubricating oil is stored. The tank part 3
Is located on the lower surface of the front end of the internal combustion engine, is fixed to a flange portion 4 formed on the lower surface of the oil pan main body 2 via a bolt (not shown), and is integrated with the oil pan main body 2. The flange portion 4 is formed along the outer periphery of the opening 2c that opens toward the tank portion 3. A baffle plate 24 is provided so as to cover the bottom wall 2 b of the oil pan main body 2 except for the opening 2 c, that is, almost the entire surface of the shallow bottom 1 a of the oil pan 1. At the rear end of the oil pan main body 2, a transmission mounting portion 9 to which a transmission (not shown) is coupled is formed. Further, a side edge 2a surrounding the entire circumference of the oil pan main body 2 includes:
A plurality of through holes 10 for mounting bolts that join the oil pan 1 and a cylinder block (not shown) are formed. Further, a flange portion 11 is formed on the upper surface of the side edge 2a of the oil pan main body 2 to be joined to a flange surface on the cylinder block side (not shown). Reference numerals 17 and 18 denote bearing caps that support the crankshaft 16, and reference numerals 19 and 20 denote counterweights and connecting rods that form part of the crankshaft 16, respectively.

In the opening 2c of the oil pan main body 2,
A first bridge portion 12 and a second bridge portion 13 along the engine width direction connecting side edges 2a along the engine longitudinal direction on both sides of the opening 2c are formed so as to cross the opening 2c. ing. Specifically, the first bridge unit 1
2 is located in the middle of the opening 2c, and the second bridge 13 is located near the rear edge of the opening 2c. Further, as shown in FIG. 1, both ends of the first bridge portion 12 are connected to boss portions 14 formed around the through holes 10 of the mounting bolts, respectively. Similarly, both ends of the second bridge 13 are connected to the boss 15 respectively.

The first bridge portion 12 is composed of a pair of vertical walls 12a extending in the vertical direction and an upper wall 12b continuous with the upper edge of the vertical walls 12a. As shown in FIG.
The cross section is formed in a U shape or a channel shape.
The lower edge of the vertical wall 12a is formed so as to linearly connect the lower ends of the bosses 14 (see FIG. 5). The second bridge portion 13 includes a vertical wall 13a extending in a vertical direction and an upper wall 1 connected to an upper edge of the vertical wall 13a.
3b, and has a L-shaped cross section as shown in FIG. The lower edge of the vertical wall 13a is formed along the height of the tip edge of the baffle plate 24 as shown in FIG. 4, and is set to be higher than the bottom surface of the bottom wall 2b. . Further, the first and second bridge portions 12 and 13 are provided at positions facing the bearing caps 17 and 18 respectively, and the first and second bridge portions 12 and 13 are provided so as not to interfere with the bearing caps 17 and 18 and the bridge portions 12 and 13. The upper wall 12b of both bridge portions 12, 13
13b is formed curved downward.

A side edge 2a of the oil pan main body 2 is provided between the first bridge portion 12 and the second bridge portion 13 so as to connect the two bridge portions 12, 13 in the longitudinal direction of the engine.
A first film-like rib 21 and a second film-like rib 22 are formed on both sides of the opening 2c along the inner surface of the opening 2c.
These first and second film-shaped ribs 21 and 22 are formed integrally and continuously with the upper walls 12 b and 13 b of the bridge portions 12 and 13. That is, the first and second film ribs 21 and 22 and the upper walls 12b and 13b are continuous so as to have the same surface (see FIG. 6). As shown in FIG. 1, the protrusion width of the first film rib 21 from the inner surface of the side edge 2 a is set to be smaller than the protrusion width of the second film rib 22.

An oval oil level gauge insertion hole 23 is provided in a corner portion between the first film-like rib 21 and the second bridge portion 13 in a cylindrical shape adjacent to the side edge 2a. An oil level gauge (not shown), which is inserted toward the tank portion 3 from an oil level gauge insertion hole above the engine (not shown), penetrates. The insertion hole 2
3 along the outer periphery of the insertion hole 23,
A corner rib 23a for connecting the film-like rib 21 and the second bridge portion 13 is provided (see FIG. 7). The corner rib 23a is formed integrally and continuously with the first film-like rib 21.

As shown in FIG. 1, three rectifying plates 5, 6, 7 extending in the front-rear direction of the engine are integrally formed on the bottom wall 2b of the oil pan main body 2 covered by the baffle plate 24. ing. As shown in FIG. 3, these current plates 5 to 7 are formed in a vertical rib shape over substantially the entire longitudinal direction of the bottom wall 2 b of the oil pan main body 2 in the engine front-rear direction. The bottom surface of the oil pan main body 2 is partitioned into four passage portions 25, 26, 27, and 28. As shown in FIG. 1, the rear end of each of the rectifying plates 5 to 7 is curved so as to face the rotation direction of the crankshaft 16 (the direction of the arrow ω in FIG. 3). That is, on the bottom surface of the oil pan 1, a rotating object such as the counterweight 19 moves in a direction indicated by an arrow ω in FIG. The ends of the flow straightening plates 5 to 7 are curved so that the ends of the passage portions 25, 26, 27, and 28 face each other in the moving direction. In the width direction of the engine, the center second straightening vane 6 is located at the center of the bottom wall portion 12b of the oil pan main body 2 (immediately below the rotation center of the crankshaft 16), and the first second straightening plate 6 is centered on this. The current plate 5 and the third current plate 7 are arranged substantially symmetrically left and right.

As shown in FIG. 3, a plurality of boss portions 29 having a height lower than the flange portion 11 are formed on the inner periphery of the oil pan main body 2 at a plurality of positions.
The baffle plate 24 is fixed to the upper surface via bolts (not shown). At the rear end of the bottom wall 2b of the oil pan main body 2, a bulging portion 30 bulging upward for mounting a transmission is provided. In FIG. 1, reference numeral 8 indicates the position of an oil drain hole formed in a cylinder block (not shown).

As shown in FIGS. 1 and 2, the ends of the current plates 5 to 7 on the opening 2c side protrude from the edge of the bottom wall 2b toward the front end of the engine and extend upward. The leading edge and the upper edge of each end of the current plates 5 to 7 are connected to the vertical wall 13a and the upper wall 13b of the second bridge portion 13, respectively. Also, shallow bottom 1a
In consideration of the flow of lubricating oil from the bottom wall 2b and the baffle plate 24, the cross-sectional area of the passages 25 to 28 formed by the respective flow regulating plates 5 to 7 and the edge of the bottom wall 2b The opening area in the plan view generated between the vertical wall 13a and the vertical wall 13a is set to be substantially equal.

As described above, in the configuration of the above embodiment, since the current plates 5 to 7 function as a kind of reinforcing member, the rigidity of the entire bottom wall 2b can be increased.
At the ends of the current plates 5 to 7 on the side of the opening 2c, the leading edge and the upper edge of the ends of the current plates 5 to 7 are connected to the vertical wall 13a and the upper wall 13b of the second bridge portion 13, respectively. The oil pan body 2 is
Is firmly connected to the side edge 2a. Thereby, the rigidity of the bottom wall 2b of the oil pan main body 2, particularly the rigidity of the portion along the opening 2c is greatly improved, so that the film vibration generated from this portion is suppressed, and the engine noise is reduced.

In particular, both ends of the second bridge 13 are
Since each of the bridge portions 1 is connected to the boss portion 15,
3 is securely supported by a cylinder block (not shown). Therefore, the bottom wall portion 2b via the second bridge portion 13
The stiffness improvement becomes more effective. In addition, by making the cross section of the second bridge portion 13 into an L-shape, the bridge portion 13
Deformation such as bending of itself is suppressed, and the deformation is reduced, so that the film vibration from the shallow bottom portion 1a is further suppressed.

The first and second bridge sections 12,
13 and the first and second film-shaped ribs 21 and 22 form a continuous reinforcing structure in a rectangular frame shape, so that the rigidity of the flange portion 11 near the opening 2c of the oil pan main body 2 is improved. . Thereby, the above-mentioned shallow bottom portion 1
Along with the improvement in the rigidity of the oil pan 1, the rigidity of the entire oil pan 1 is improved, and the engine noise is reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of an entire oil pan according to the present invention.

FIG. 2 is a sectional view of the entire oil pan taken along line AA in FIG.

FIG. 3 is a sectional view of the oil pan main body taken along line BB of FIG. 1;

FIG. 4 is a cross-sectional view along the line CC.

FIG. 5 is a cross-sectional view along the line DD.

FIG. 6 is a cross-sectional view of the film-like rib taken along the line EE in FIG. 1;

FIG. 7 is a sectional view of the oil level gauge insertion hole along the line FF in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Oil pan 2 ... Oil pan main body 3 ... Tank part 5, 6, 7 ... Rectifying plate 12 ... First bridge part 12a, 13a ... Vertical wall 12b, 13b ... Upper wall 13 ... Second bridge part

Claims (6)

[Claims] An internal combustion engine has a side edge which is bolted to a lower surface of a cylinder block on an entire circumference, a bottom wall portion serving as a shallow bottom at one end side in the front-rear direction of the engine, and a bottom surface at the other end side. An oil pan body that is integrally cast with an opening,
An oil pan of an internal combustion engine, comprising: a metal plate that stores lubricating oil and is mounted on a lower surface of the opening of the oil pan main body. A bridge portion is formed integrally on the bottom surface of the oil pan main body, and is formed integrally with the oil pan main body, and a bridge portion along the engine width direction connecting side edges along the engine longitudinal direction is formed integrally with the oil pan main body. An oil pan for an internal combustion engine, wherein an end on the side of the section is connected to the bridge section. 2. The bridge portion is disposed at a position crossing the opening, and the end of the current plate on the opening side projects into the opening from the edge of the bottom wall on the opening side. The oil pan of an internal combustion engine according to claim 1, wherein: 3. The device according to claim 1, wherein both ends of the bridge portion are connected to positions of through holes of mounting bolts for connecting the oil pan main body and the cylinder block, respectively. Oil pan for internal combustion engine. 4. The bridge portion comprises a vertical wall extending in a vertical direction, and an upper wall continuous with an upper edge of the vertical wall,
The oil pan of an internal combustion engine according to any one of claims 1 to 3, wherein a cross section is formed in an L shape. 5. The oil pan of an internal combustion engine according to claim 4, wherein a lower edge of the vertical wall of the bridge portion is set higher than a bottom surface of a bottom wall portion of the oil pan main body. 6. An end portion of the current plate is extended upward, and a front edge and an upper edge of the end portion of the current plate are connected to a vertical wall and an upper wall of the bridge portion, respectively. The oil pan for an internal combustion engine according to claim 4 or 5, wherein