The present invention relates to an oil pan structure, and more specifically to an oil pan structure provided in a lower portion of an engine for a vehicle.
An oil pan provided in a lower portion of an engine for a vehicle has an approximately rectangular bottom wall extending in a direction of each cylinder line as viewed from the upper side, as disclosed in, for example, U.S. Patent Publication No. 2009/0151690. The oil pan has a deep bottom section provided on one side of the bottom wall and a shallow bottom section provided on the other side of the bottom wall. Plural reinforcing ribs are formed on an inside of both the deep bottom section and the shallow bottom section, and plural reinforcing ribs are formed also on an outside of the shallow bottom section. In this way, the conventional oil pan structure has plural reinforcing ribs provided on the bottom wall, which can not only increase rigidity of the bottom wall, but also reduce vibration of the bottom wall.
However, the above oil pan structure may result in an increased weight of the oil pan, due to the reinforcing ribs.
The present invention is made so as to address such a problem. Therefore, a purpose of the invention is to provide an oil pan structure, wherein the rigidity of the bottom wall could be increased while reducing the weight of the oil pan.
To achieve the above purpose, in accordance with an aspect of the invention, an oil pan structure of an engine for a vehicle comprises an oil pan attached to a lower portion of the engine having plural cylinders, wherein
the oil pan has an approximately rectangular bottom wall which accumulates oil continually and extends in a direction of each cylinder line as viewed from an upper side, a long side wall extending parallel to the cylinder line, and a short side wall extending perpendicular to the cylinder line,
the approximately rectangular bottom wall is surrounded by the long side wall and the short side wall,
the bottom wall has a deep bottom section provided approximately in a center of the bottom wall and in a portion where the oil is pumped up, a shallow bottom section which has a depth that is shallower than that of the deep bottom section, and connecting wall section extending vertically and connecting the deep bottom section with the shallow bottom section, and
the shallow bottom section is provided on both sides of the deep bottom section.
According to above configuration, the bottom wall is divided into the deep bottom section and the shallow bottom section which can be formed respectively in a flat shape. And the deep bottom section is connected with the shallow bottom section via the connecting wall section which extends vertically and functions as a reinforcing rib. This could advantageously result in increasing the rigidity of the bottom wall and reducing vibration of the bottom wall without increasing thickness of the bottom wall or providing excessive reinforcing ribs on the inside of the bottom wall. Additionally, by providing the shallow bottom sections on both sides of the deep bottom section, it might restrain the oil from moving to one side during accelerating, decelerating or curve traveling of the vehicle. This can advantageously result in keeping the oil level high in the deep bottom section.
Preferably, the bottom wall might have first deep bottom extending sections extending respectively from the deep bottom section in both directions parallel to the cylinder line as viewed from the upper side, and second deep bottom extending sections extending respectively from the first deep bottom extending sections in at least one of both directions perpendicular to the cylinder line as viewed from the upper side. According to above configuration, a length of the connecting wall section might be increased as the second deep bottom extending sections are provided so as to extend further from the first deep bottom extending sections.
Preferably, the second deep bottom extending sections might extend respectively from the first deep bottom extending sections so as to be positioned diagonally across the deep bottom section. And the connecting wall section might connect the deep bottom section, the first deep bottom extending section and the second deep bottom extending section with the shallow bottom section, and might extend in an approximately L shape as viewed from the upper side. According to above configuration, the rigidity of the bottom wall could be further increased as the connecting wall section might extend in an approximately L shape in the bottom wall.
Preferably, the bottom wall might have deep bottom extending sections extending respectively from the deep bottom section in four directions parallel to or perpendicular to the cylinder line as viewed from the upper side, and the shallow bottom section might be positioned outside of each deep bottom extending section. According to above configuration, the rigidity of the bottom wall could be further increased as the connecting wall section in an approximately L shape might be positioned around the deep bottom section.
Preferably, the short side wall and the bottom wall might be connected to each other via a step wall section protruding inward of the oil pan. According to above configuration, the oil level can be kept high without reducing much space in the oil pan.
Preferably, the bottom wall, the long side wall and the short side wall might be formed by casting light alloy. According to above configuration, a weight of the whole the oil pan structure could be reduced, and manufacturing cost could also be reduced.
According to above oil pan structure, the rigidity of the bottom wall could be increased while reducing the weight of the oil pan.
Next, an embodiment of the invention is described with reference to the appended drawings. First, with reference to
As shown in
As shown in
The oil pan 4 includes a bottom wall 10 of a substantially rectangular shape in the top view, which continually reserves engine oil, and a side wall section 20 extending upwardly so as to surround the bottom wall 10. Thus, it will be appreciated that the bottom wall 10 of the oil pan extends in a direction of the cylinder lines of the engine, which are parallel to the engine front-and-rear direction, such that a long axis of the rectangular shape of the bottom wall 10 is oriented in the engine front rear direction, and a short axis of the rectangle is oriented in the width direction.
The side wall section 20 includes a pair of long side wall sections 21a and 21b extending in the long-side direction (the longitudinal direction or the engine front-and-rear direction), and a pair of short side wall sections 22a and 22b extending in the short-side direction (the transverse direction or the engine width direction). A cylinder-block-attachment flange part 20a is formed in an upper end part of the side wall section 20 so as to join to the cylinder block 2. As shown in
The bottom wall 10 includes a deep bottom section 11 that is located substantially at the center of the rectangular-shaped bottom wall 10 in the top view and used as an oil pumping part, and a shallow bottom section 14 that is shallower than the deep bottom section 11. Further, the bottom wall 10 includes deep bottom extending sections 12a and 12b extending from the deep bottom section 11 to both directions of the engine front direction and the engine rear direction, which are the longitudinal direction in the top view, and deep bottom re-extending sections 13a and 13b extending from both the deep bottom extending sections 12a and 12b to the vehicle front direction and the vehicle rear direction, respectively, which are the short-side direction in the top view.
The deep bottom section 11, the deep bottom extending sections 12a and 12b, and the deep bottom re-extending sections 13a and 13b are connected with the shallow bottom sections 14a and 14b so that they continue via a connecting wall section 15 extending in the up-and-down direction. In this embodiment, the deep bottom section 11, the deep bottom extending sections 12a and 12b, and the deep bottom re-extending sections 13a and 13b are continuously formed without a level difference. Preferably, these sections are configured to form the same plane, and this resulted plane may be a horizontal surface or may be a sloped surface.
In this embodiment, because the deep bottom section 11, the deep bottom extending sections 12a and 12b, and the deep bottom re-extending sections 13a and 13b are arranged as described above, the shallow bottom sections 14a and 14b are located at two diagonal places in the bottom wall 10 across the deep bottom section 11.
For this reason, the connecting wall section 15 extends in a substantially L shape in the top view at two places in the bottom wall 10. In detail, the connecting wall section 15a located in the vehicle front side and the connecting wall section 15b located in the vehicle rear side are formed, and each has a configuration such that a part extending in the engine longitudinal direction and a part extending in the engine transverse direction (engine width direction) are coupled substantially at an angle of 90°.
As shown in
In order to avoid interference with the suction side end part 30a, a concave portion 18 is formed in a part of the shallow bottom section 14a. The suction side end part 30a is arranged so as to fit in the concave portion 18. Note that, in this embodiment, a part of the connecting wall section 15a is cut so as to form the concave portion 18, but, without limiting to this configuration, the oil strainer 30 may be arranged without the concave portion 18 being formed to not cut the part of the connecting wall section 15a, for example.
Level difference wall sections 16a and 16b are formed in the connecting part between the short side wall sections 22a and 22b and the bottom wall 10 so that each is depressed inwardly of the oil pan 4. Attachment boss parts 19 for attaching a baffle plate (not shown) upwardly from the bottom wall 10 are formed at four places. These are formed so as to avoid interference with the oil strainer 30.
Next, referring to
Next, an operation of the oil pan structure of this embodiment is described. As described above, the oil pan 4 of this embodiment has the bottom wall 10 of the substantially rectangular shape in the top view. The deep bottom section 11 used as the oil pumping part is provided to a substantially center part of the bottom wall 10 in the longitudinal direction and the short-side direction (the width direction or the transverse direction). The deep bottom extending sections 12a and 12b extend in the longitudinal direction from the deep bottom section 11 to both sides, respectively.
The deep bottom re-extending sections 13a and 13b are formed so as to extend from the deep bottom extending sections 12a and 12b to the vehicle front (engine left) and to the vehicle rear (engine right), respectively. The deep bottom section 11, the deep bottom extending sections 12a and 12b, and the deep bottom re-extending sections 13a and 13b are formed so that their bottom surfaces continue without a level difference mutually.
Among the bottom wall 10, parts other than the deep sections (i.e., the deep bottom section 11, the deep bottom extending sections 12a and 12b, the deep bottom re-extending sections 13a and 13b), the shallow bottom sections 14a and 14b shallower than the deep sections are formed at least on both sides of the deep bottom section 11 in the longitudinal direction or in the short-side direction (the width direction or the transverse direction). The deep sections and the shallow sections (the shallow bottom sections 14a and 14b) are connected with each other so that they continue by the connecting wall sections 15a and 15b extending in the up-and-down direction, respectively.
As described above, because the rectangular section of the bottom wall 10 in the plan view is sectioned into the deep sections and the shallow sections, film vibration (vibration of the bottom wall) can be reduced, and the bottom surface can be configured in the planar shape without providing inner rib(s) in each section. In this embodiment, because the connecting wall section 15 that connects both the sections functions as reinforcing rib(s), thereby, a surface rigidity of the bottom wall 10 can be improved. Further, because the connecting wall sections 15a and 15b do not have a configuration which partially projects inside unlike the conventional inner rib(s), they do not increase in weight, are simple in structure, and can reduce a manufacture cost.
In this embodiment, because the shallow bottom section 14 is provided, an oil level in the deep bottom section 11 can be maintained high. Further, in this embodiment, the shallow bottom sections 14a and 14b are located on both sides of the deep bottom section 11, which is the oil pumping part, at least in the longitudinal direction or the short-side direction (the width direction or the transverse direction), as described above. Alternatively, the shallow bottom sections 14a and 14b are specifically located diagonally to the deep bottom section 11. Thus, because the shallow bottom sections 14a and 14b are located on both sides of the deep bottom section 11 in the engine front-and-rear direction and the engine left-and-right direction, even if the engine oil slants toward either direction inside the oil pan 4 at the time of turning, accelerating, braking and the like, the suction side end part 30a of the oil strainer 30 can be held below the oil surface.
Further, in this embodiment, because the level difference wall sections 16a and 16b are formed in the connecting part of the short side wall sections 22a and 22b and the bottom wall 10 so that they are depressed inwardly of the oil pan 4, the oil level can be maintained high, sacrificing less inner space. Further, by forming the level difference wall sections 16a and 16b as described above, the surface rigidity of the bottom wall 10 can be further increased. In this embodiment, although the level difference wall section is formed along with the short side wall sections 22a and 22b, the level difference wall section may be formed along the long side wall sections 21a and 21b, without limitation.
In this embodiment, because the connecting wall sections 15a and 15b are formed in a substantially L shape and an inverted L shape in the top view, respectively, the surface rigidity of the bottom wall 10 can be further increased. In this embodiment, because the shallow bottom sections 14a and 14b are arranged diagonally, and thereby, the substantially L shaped connecting wall sections 15a and 15b are also located diagonally, the surface rigidity in the engine front-and-rear direction can be increased with a sufficient balance, and the film vibration can be suppressed.
Next, modified embodiments of the invention are described with reference to
In the example of
In the example of
In the example of
As described above, even if the bottom wall 10 is divided into the deep sections and the shallow sections, because the connecting wall section 15, which couples these sections serves as the reinforcing rib, the surface rigidity of the bottom wall 10 can be increased as a whole, and the film vibration (vibration of the bottom wall) can be reduced.
In the above embodiment, although the example in which the engine 1 is the transverse engine, the engine may alternatively be, but not limited to, a longitudinal engine or north-south engine where the engine is arranged so that its longitudinal direction is oriented in the vehicle front-and-rear direction. Also in the oil pan 4 arranged as described above, the slanting of the engine oil can be suppressed at the time of accelerating, braking, and turning, to maintain the deep bottom section 11 or the suction side end part 30a of the oil strainer 30 below the oil surface.
It should be understood that the embodiments herein are illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within metes and bounds of the claims, or equivalence of such metes and bounds thereof are therefore intended to be embraced by the claims.
Number | Date | Country | Kind |
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2009-226709 | Sep 2009 | JP | national |