JP3823761B2 - Oil pan - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oil pan attached to a lower surface of a cylinder block of an internal combustion engine, and more particularly to an oil pan having a flange bolted to the lower surface of the cylinder block.
[0002]
[Prior art]
The oil pan receives oil flowing down from the cylinder block and stays on the bottom side, and stably supplies the oil to an oil pump provided at the deep bottom. Such an oil pan is made of a steel plate whose thickness is suppressed for oil cooling and weight reduction. Such an oil pan is bolted after the flange on the outer periphery of its upper edge is joined to the lower surface of the cylinder block. In particular, the flange of the oil pan is a reinforcing member in order to equalize the tightening force in the longitudinal direction of the flange. Many are bolted through.
By the way, the oil pan integrated with the cylinder block is vibrated when the engine is driven, and the oil in the oil pan vibrates at that time. The oil pan receives the excitation force corresponding to the oil vibration, and the bottom wall and the side wall on the deep bottom side, which is less rigid than the shallow bottom portion, are displaced.
[0003]
For example, as shown in FIGS. 6A and 6B, when the oil in the oil pan 100 vibrates, the bottom wall 110 on the deep bottom side repeats deformation in particular. As a result, the bottom wall 110 on the deep bottom side is displaced by receiving the vertical vibration force (see symbol h1), and the side wall 120 on the deep bottom side is displaced left and right (see symbol h2) in conjunction therewith. At this time, the flange 140 extends laterally from the upper end portion of the side wall 120 via the bent portion 130, and the flange is bolted to the lower surface of a cylinder block (not shown) via the reinforcing member 150. For this reason, stress concentration occurs in the vicinity of the flange portion e up to the vicinity of the bent portion 130 and the contact portion with the reinforcing member 150 of the flange 140 that is continuous with the bent portion 130. 100 durability will be reduced.
[0004]
Therefore, in order to suppress such bending deformation of the flange vicinity portion e, the thickness of the stiffener is relatively large as disclosed in Utility Model Registration No. 2574962 to increase the flange lower surface suppression width B of the reinforcing member 150. Or, an inner stiffener is continuously formed on the inner end side of the stiffener, thereby suppressing the bending portion and the side wall from being displaced.
[0005]
[Problems to be solved by the invention]
Here, as disclosed in Utility Model Registration No. 2574962, assuming that a stiffener having a relatively large thickness and a large flange lowering width is used, in this case, the entire length of the flange of the oil pan and the stiffener are equal. In this manner, the durability of the oil pan is ensured. However, when such a configuration is adopted, the weight of the stefner increases, leading to an increase in the weight of the entire oil pan. For this reason, the improvement which can aim at the weight reduction and durability of an oil pan is desired.
An object of the present invention is to provide an oil pan based on the problems as described above, which can suppress an increase in weight, suppress deterioration with time in the vicinity of the flange of the oil pan, and prevent deterioration of the durability of the oil pan. And
[0006]
[Means for Solving the Problems]
The invention of claim 1, and a shallow bottom portion and a deep portion in the oil pan to the lower surface of the cylinder block upper edge outer periphery of the flange is bolted through the reinforcing member on which is bonded, said flange The holding surface is wider than the shallow bottom side, and further thicker than the shallow bottom side and the oil pan. The flange holding surface extends from the flange and the flange. It is characterized in that a rounded portion is provided in continuous surface contact over a bent portion reaching the side wall of the oil pan .
Thus, since the reinforcing member on the deep bottom side is formed of a steel material having a wider flange restraining surface than the shallow bottom side and thicker than the shallow bottom side and the oil pan, the entire In addition, it is possible to suppress fatigue deterioration due to transient displacement and stress generation near the flange on the deep bottom side. Moreover, the flange holding surface of the reinforcing member on the deep bottom side side is provided with a rounded portion that continuously contacts the surface of the flange and the bent portion that extends from the flange and reaches the side wall of the oil pan. In particular, it is possible to suppress excessive displacement and stress generation of the bent portion where stress is likely to concentrate, and it is possible to prevent a decrease in durability of the oil pan.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
1 to 3 show an oil pan 1 as an embodiment of the present invention.
The oil pan 1 is attached to a lower portion of a cylinder block 2 of a vehicle engine (not shown) and is provided with an opening 3 (see FIG. 4A) for receiving oil flowing down from the inside of the cylinder block 2. It is formed as a plate-shaped sheet metal material.
[0010]
Here, the oil pan 1 is provided with a flange 4 on the outer periphery of the upper edge portion, and a reinforcing member 5 is overlapped on the flange lower surface f, and then tightened and coupled to the mounting surface f of the cylinder block with a plurality of bolts.
The cylinder block 2 has a mounting flange 6 formed so as to protrude outward from the cylinder block 2 over the entire area of the lower peripheral edge thereof. The mounting flange 6 is continuously formed with a downward mounting surface f0 along the peripheral longitudinal direction, and screw holes 7 (see FIG. 4A) are sequentially formed at predetermined intervals along the peripheral peripheral direction. The
[0011]
As shown in FIGS. 1 and 3, the oil pan 1 includes a bottom wall 8, a side wall 9, and a flange 4 that extends from the upper end of the side wall 9 via a bent portion 11 (see FIG. 4A). A deep bottom m is formed on the front side (left side in FIG. 1) of the oil pan 1 in the longitudinal direction X, and a shallow bottom n is formed on the rear side. Here, by providing the deep bottom portion m on the front side, it is easy to improve the cooling performance of the oil in the deep bottom portion m by the traveling wind. In addition, the code | symbol D of FIG. 2 shows the drain port, and this is closed with the drain volt | bolt which is not shown in figure.
[0012]
The oil pan 1 has a relatively small thickness for oil cooling and weight reduction, and is manufactured by pressing a single steel plate. In addition, the bottom wall 8 and the side wall 9 of the oil pan 1 are formed with beads v for strengthening rigidity at appropriate positions, but the rigidity of the bottom wall 8 and the side wall 9 on the deep bottom m side where the amount of squeezing in the press working is relatively large. Is smaller than the shallow bottom n side.
As shown in FIGS. 4A and 4B, the oil pan 1 is formed with a bent portion 11 extending from the upper end of the side wall 9 and further extending from the upper end of the bent portion 11 with the flange 4 extending in the horizontal direction. Has been.
[0013]
The flange 4 is superimposed on the mounting surface f0 via the seal material 12, and the reinforcing member 5 having a substantially cross-sectional rectangle is superimposed on the lower surface f of the flange, and the flange 4, the sealing material 12 and the reinforcing member 5 are continuously passed therethrough. The bolt 13 is inserted into the mounting hole g, the bolt 13 is screwed into the screw hole 7 of the mounting surface f0, and the oil pan 1 is fastened and coupled to the cylinder block 2. As shown in FIGS. 2 (a) and 2 (b), the reinforcing member 5 is formed of a thick steel material, and as a whole has a shape that continuously contacts the annular flange lower surface f, and includes a plurality of divided reinforcing pieces 5a. 5b, 5c is configured as an assembly.
[0014]
That is, the reinforcing member 5 is disposed between the front and rear divided reinforcing pieces 5a and 5c, and the front and rear divided reinforcing pieces 5a and 5c, which are arranged in front and rear, and the left and right sides of the front and rear divided reinforcing pieces. It is provided with a straight left and right divided reinforcing piece 5b arranged opposite to each other in a state of being butted against the end. Among these, the cross-sectional shape of the substantially U-shaped front divided reinforcing piece 5a superimposed on the flange 4 on the deep bottom m side which is the front side is as shown in FIGS. 2 (b) and 4 (a). The thickness t1 is thicker than the other reinforcing pieces 5b and 5c, and the flange holding width b1 of the flange holding surface is set larger than the other reinforcing pieces 5b and 5c. In particular, a rounded portion r is formed on the inner side (side wall 9 side) in the flange restraining width b1 direction, and the rounded portion r is formed to be in surface contact with the upper end side of the bent portion 11 of the oil pan 1.
[0015]
On the other hand, the cross-sectional shapes of the left and right divided reinforcing pieces 5b and the rear divided reinforcing piece 5c are the same. As shown in FIG. 4B, the thickness t2 is relatively thin, and the flange holding width b2 of the flange holding surface is also compared. In this case, the rounded portion r (see FIG. 4A) is excluded.
Each of the front and rear divided reinforcing pieces 5a, 5c and the left and right divided reinforcing pieces 5b is formed with a plurality of attachment holes g through which the fastening bolts 13 are inserted at predetermined intervals. It is assumed that the oil pan 1 is fastened to the mounting surface f0 of the cylinder block 2 with a plurality of bolts 13 using the reinforcing member 5 including the front and rear divided reinforcing pieces 5a and 5c and the left and right divided reinforcing pieces 5b.
[0016]
In this case, the substantially U-shaped front divided reinforcing piece 5a has a relatively large flange restraining width b1 of the flange restraining surface, and is in contact with the flange 6 on the deep bottom m side and the upper end of the bent portion 11 to the deep bottom m side. The displacement of the flange 6 and the bent portion 11 can be suppressed. On the other hand, the rear divided reinforcing piece 5c and the left and right divided reinforcing pieces 5b have a relatively small flange holding width b2 on the flange holding surface, and abut only on the main part of the flange lower surface f1 of the flange 6 on the shallow bottom side.
[0017]
It is assumed that the engine having such an oil pan 1 attached to the cylinder block 2 is driven and the oil in the oil pan 1 vibrates. At this time, the deep bottom m side is relatively less rigid than the shallow bottom n side, and in particular, the forward facing portion (shown as 9f in FIG. 1) of the side wall 9 on the deep bottom m side is a lateral portion (front portion in FIG. 1). ) Is less rigid. Further, a large amount of oil stays on the deep bottom m side compared to the shallow bottom n side, and the bottom wall on the deep bottom m side tends to be greatly displaced by receiving a relatively large oil load. However, here, the bent portion 11 and the flange 4 extending from the upper end portion of the side wall 9 on the deep bottom m side abut against the substantially U-shaped front divided reinforcing piece 5a, and the flange 4, the bent portion 11 and the side wall 9 portion. The displacement of the flange vicinity portion e formed in the vicinity of the upper end of the flange is suppressed. For this reason, the displacement of the flange vicinity portion e is suppressed, the amount of stress generation is reduced, and the durability against the deterioration with time can be sufficiently prevented.
[0018]
At this time, the shallow bottom n side is more rigid than the deep bottom m side, and the amount of oil remaining on the shallow bottom n side is small, so that the bottom wall 8 and the side wall 9 on the shallow bottom n side receive an oil load. The amount of displacement is extremely small. For this reason, even if the holding width b2 of the rear divided reinforcing piece 5c and the left and right divided reinforcing pieces 5b is relatively small, the displacement itself is small, so the amount of stress generated in the flange vicinity e on the shallow bottom n side is relatively small. It is small and can sufficiently prevent a decrease in durability against deterioration over time. Moreover, since the restraining width b2 of the rear divided reinforcing piece 5c and the left and right divided reinforcing pieces 5b and the thickness t2 are relatively small with respect to the front divided reinforcing piece 5a, the weight of the reinforcing member 5 as a whole can be reduced.
Thus, the oil pan using the reinforcing member 5 of FIG. 1 suppresses fatigue deterioration due to excessive displacement and stress generation of the flange vicinity portion e on the deep bottom m side, while suppressing an increase in weight as a whole. The deterioration of the durability of the oil pan can be prevented.
[0019]
In the above description, the reinforcing member 5 is limited only by the front divided reinforcing piece 5a, and the width b1 and the thickness t1 are set to be relatively large. However, depending on the case, in addition to the front divided reinforcing piece 5a, FIG. As shown by a two-dot chain line, only the portion facing the deep bottom portion m of the left and right divided reinforcing piece 5b may be formed to have a relatively large suppression width b1 or thickness t1. In this case, the weight reduction rate as a whole of the reinforcing member 5 is somewhat reduced, but the deformation amount and the stress generation amount of the flange vicinity portion e of the portion facing the deep bottom portion m can be more reliably reduced.
In the above description, the reinforcing member 5 is composed of a substantially U-shaped front and rear divided reinforcing piece and a straight left and right divided reinforcing piece, but in some cases, the front divided reinforcing piece is further divided into left and right. Alternatively, left and right front left and right divided reinforcing pieces may be formed. In this case, it is possible to absorb an error between components such as a shift of a mounting hole, and to improve the mounting performance, compared to the case of using a single front divided reinforcing piece.
[0020]
As described above, the substantially U-shaped front and rear divided reinforcing pieces 5a and 5c and the straight left and right divided reinforcing pieces 5b constituting the reinforcing member 5 both adopt a substantially rectangular cross section. As shown in (a) and (b), the inner thickness ti of the front divided reinforcing piece 5a ′, the rear divided reinforcing piece 5c ′, and the left and right divided reinforcing piece 5b ′ is set to the outer thickness t1, t2. The flange restraining widths b3 and b4 may be increased while increasing the flange restraining width, thereby suppressing an excessive weight increase. In this case, the entire inner region in the width direction of the flange pressing surface is in contact with the bent portion 11 and the upper portion of the side wall 9, but in some cases, a gap (not shown) is secured on the upper side of the side wall 9. It may be configured not to abut but to abut only at an excessive displacement and suppress only an excessive displacement.
[0021]
In the above description, the pre-divided reinforcing piece 5a shown in FIGS. 1 and 2 is substantially U-shaped, but in some cases, a pair of L-shaped pre-divided pieces as shown by a two-dot chain line in FIG. 2 (a). You may form as reinforcement piece half part 5a-1, 5a-2, and attachment is facilitated in this case.
Furthermore, the above-described oil pan is described as being made of steel, but the present invention is not limited to this, and the present invention can be applied to an oil pan made of aluminum alloy or resin, and the oil pan 1 shown in FIG. Similar effects can be obtained.
[0022]
【The invention's effect】
As described above, according to the first aspect of the present invention, the reinforcing member on the deep bottom side has a wider flange holding surface than the shallow bottom side, and is thicker than the shallow bottom side and the oil pan. Since it is formed of steel, it is possible to suppress fatigue deterioration due to transient displacement and stress generation in the vicinity of the flange on the deep bottom side while suppressing an increase in the overall weight. Moreover, the flange holding surface of the reinforcing member on the deep bottom side side is provided with a rounded portion that continuously contacts the surface of the flange and the bent portion that extends from the flange and reaches the side wall of the oil pan. In particular, it is possible to suppress excessive displacement and stress generation of the bent portion where stress is likely to concentrate, and it is possible to prevent a decrease in durability of the oil pan.
[Brief description of the drawings]
FIG. 1 is a side view of an oil pan attached to a cylinder block as one embodiment of the present invention.
FIG. 2 shows the oil pan of FIG. 1, wherein (a) is a bottom view and (b) is a side view of a reinforcing member attached with the oil pan.
3 is an exploded perspective view of the oil pan of FIG. 1. FIG.
4 is a partially enlarged view of a mounting portion of an oil pan to a cylinder block according to an embodiment of the present invention. FIG. 4 (a) is a cross-sectional view taken along line AA in FIG. ) Is a cross-sectional view taken along line BB or CC in FIG. 3 on the shallow bottom side.
FIGS. 5A and 5B are cross-sectional views of a modified example of a reinforcing member used in a mounting portion of an oil pan to a cylinder block according to an embodiment of the present invention, where FIG. 5A is a deep bottom side and FIG. is there.
6A and 6B are diagrams for explaining displacement during vibration of a conventional oil pan, where FIG. 6A is a perspective view illustrating a deformed state, and FIG. 6B is an explanatory view of a deformation amount and a deformation direction.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Oil pan 2 Cylinder block 4 Flange 5 Reinforcement member 5a Front division reinforcement piece 5b Left and right division reinforcement piece 5c Rear division reinforcement piece 13 Bolt n Shallow bottom part m Deep bottom part f Bottom face f0 Mounting surface b1, b2 Flange restraining width e Flange vicinity part

Claims (1)

In an oil pan that has a shallow bottom portion and a deep bottom portion and is bolted via a reinforcing member in which a flange holding surface is in contact with the flange after the flange on the outer periphery of the upper edge portion is joined to the lower surface of the cylinder block,
The reinforcing member on the deep bottom side is formed of a steel material in which the width of the flange pressing surface is wider than that of the shallow bottom side, and the wall thickness is thicker than that of the shallow bottom side and the oil pan. The oil pan is provided with a flange portion extending from the flange and a bent portion extending from the flange and reaching the side wall of the oil pan, and continuously in surface contact .

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