JP2002276324A - Oil pan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a noise due to engine operation, by making an oil pan mounted to a lower surface of a crankcase of an engine function as a reinforcing member for reducing vibration at a crankcase skirt part. SOLUTION: This oil pan comprises: an oil pan body mounted to the lower surface of the crankcase of the engine and molded preferably by an aluminum alloy; and an oil reservoir of sheet metal mounted to a lower surface of the oil pan body. The oil pan body comprises: a shallow dish part provided with a cylindrical surface or a tub-like curved wall similar to the cylindrical surface which becomes gradually deep toward an engine center surface passing to a crankshaft line from an end in a width direction of a marginal flange fixed to the lower surface of the crankcase; a pipe-like space having a closed section formed at a lower side of front and back parts of both ends in a width direction of the shallow dish part; and a flange formed on a lower surface in a last half part of the shallow dish part and provided with the oil reservoir attached thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil pan provided for storing and cooling oil which has lubricated and cooled relative sliding and rotating parts of engine components.

[0002]

2. Description of the Related Art In an engine, in particular, a vehicle engine, an exciting force due to an explosion pressure in each cylinder and a vibration based on various components such as an inertial force of a crank mechanism are transmitted to a crankshaft. The vibration is transmitted to the main bearing cap that supports the crankshaft in cooperation with the partition wall that forms the crankshaft bearing of the crankcase or the cylinder block, and this vibration is further transmitted to the skirt of the crankcase or the cylinder block, and Dissipated outside as noise. The main mode of vibration of the crankcase skirt is that the lower end of the skirt reciprocates in a direction perpendicular to the crankshaft, and this vibration is flange-connected to the lower end opening of the skirt. It is known that an unpleasant noise is generated by vibrating a thin steel plate oil pan.

[0003] Conventionally, a pair of longitudinal members extending substantially in the direction of the crank axis, which are tightened and fastened by bolts or the like, are provided at the lower end opening of the crankcase skirt, and each of the vertical members is juxtaposed at right angles to the crank axis. Both ends are provided with a plurality of beam portions integrally connected to the vertical member, and a reinforcing member generally called by various names such as a ladder frame, an under frame or a lower case is provided, and a crank axis of the skirt portion is provided. Numerous proposals have been made to suppress vibrations displaced in the direction perpendicular to the direction and reduce the operating noise of the engine. For the reinforcing member such as the ladder frame, a main bearing whose beam portion supports the crankshaft is provided. Some are configured to also serve as caps.

However, even if the ladder frame or the lower case, in which the beam portion also serves as the main bearing cap, is mounted on the lower surface of the crankcase skirt portion, the generation of noise cannot be sufficiently prevented. There is a demand for noise reduction. Therefore, in general, an oil pan is formed by pressing a thin steel plate and is easily transmitted as a noise source by causing resonance due to vibration transmitted directly from the skirt portion of the crankcase or transmitted through the ladder frame or the like. In addition to the original function of improving the structure and collecting and temporarily storing oil that lubricates and cools the engine parts, as a reinforcing member that effectively suppresses vibration of the crankcase skirt and ladder frame, etc. It is desirable to be configured to work.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances. An oil pan is provided with a highly rigid oil pan main body mounted on a lower surface of a crankcase skirt or a ladder frame or the like. The oil pan mounted on the lower surface of the oil pan main body. By devising the structure of the oil pan main body, the operation noise of the engine can be more effectively reduced than before. The main purpose is to provide a simple configuration.

[0006]

In order to achieve the above object, the present invention provides a peripheral flange fixed to a lower surface of a crankcase of an engine, a shallow plate formed at a portion surrounded by the peripheral flange, An oil sump mounting flange formed on the lower surface of one side in the longitudinal direction of the shallow dish portion, and the oil sump mounting flange is juxtaposed on both sides in the width direction of the shallow dish portion. An oil pan body having a tubular space having a closed cross-section structure extending to the inside of the flange, and a sheet metal oil reservoir having a flange formed at an upper peripheral portion thereof fastened to the oil reservoir mounting flange. And
One end of the tubular space is connected to an oil strainer disposed in the oil reservoir at one end, and the other end is connected to an oil pump of the engine. Things. In the present invention, it is preferable that the above-mentioned shallow dish portion is provided with a trough-shaped curved wall having a concave surface on a cylindrical surface or an approximate upper surface thereof.

Further, in the present invention, the above-mentioned shallow plate portion includes:
A plurality of beam portions are provided between the cylinders of the crankcase and abut on a main bearing cap that supports a crankshaft, and the oil pan body is attached to the main bearing cap by a mounting bolt that passes through the beam portion. Tightening is preferable, and the other of the tubular spaces is desirably formed as an oil passage for guiding a part of the oil flowing down from each part of the engine to the oil pan body to the oil reservoir.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to FIGS. First, FIG.
2, reference numeral 10 generally indicates a vehicle diesel engine. The engine 10 includes a crankcase or a cylinder block 12 having a plurality of cylinders, and a cylinder head 14 mounted on an upper end of the crankcase 12.
And a rocker cover 16 mounted on the upper end of the cylinder head 14. In the illustrated case, the crankcase 12 includes a cylinder block portion 12a and left and right skirt portions 12b extending downward from the cylinder block portion 12a.
And a lower case 12c having a known ladder frame structure attached to the lower end of the skirt portion 12b.

The skirt portion 12b has a partition wall 1 extending downward from a portion between the cylinders of the cylinder block portion 12a.
8, and the partition wall 18 is provided with a bearing portion 20 that supports the upper half portion of the journal portion of the crankshaft 20. The lower case 12c is provided with a pair of left and right vertical members 24 extending substantially parallel to the axis of the crankshaft 20, and the upper surface thereof is in contact with the lower surface of the partition wall 18, and both ends are integrated with the vertical member 22. And a beam portion 26 which is coupled to the partition 18 to support the lower half of the journal portion of the crankshaft 20, as best seen in FIG. A main bearing cap is formed. The beam portion or the main bearing cap 26 includes left and right tightening bolts 28 disposed on both sides of the journal portion of the crankshaft 20 and the skirt portion 12b.
Are fastened to the partition wall 18 by left and right tightening bolts 30 arranged close to each other.

In the lower case 12c, a flange formed at an upper end of the vertical member 24 is fastened by a plurality of tightening bolts (not shown) arranged on corresponding flanges formed at a lower end of the skirt portion 12b. Thereby, it is fixed to the skirt portion 12b. An oil pan 32, which will be described in detail later, is attached to the lower end of the lower case 12c. In FIG. 1, 3
4 is a timing gear case for storing a gear train for transmitting the rotation of the crankshaft 20 to the valve mechanism of each cylinder housed in the cylinder head 14; 36 is a flywheel mounted on the output end of the crankshaft 20; 38 is mounted on the front end of the crankshaft 20 and includes a water pump (not shown)
A crank pulley that drives a fuel injection pump, a radiator fan, and the like, 40 is an oil pump that is driven in conjunction with the crankshaft 20, and 42 is an oil strainer disposed in an oil pan 32. The lower case 12c
May not be provided in engines 10 having different specifications. In this case, the main bearing cap 26 is formed as an independent member and is fastened to the partition 18 by a tightening bolt 28 so that the journal portion of the crankshaft 20 is formed. The skirt 12b is supported by the lower case 1 in FIG.
The oil pan 32 is attached to the lower end of the flange 2 so as to extend downward to the vicinity of the lower surface of the oil pan 2. Therefore, in claim 1 of the present invention, in the case of the crankcase 12 having the lower case 12c, the term "crankcase lower surface" means the lower surface of the lower case 12c.
In the case of the crankcase 12 having no 2c, it means the lower surface of the skirt portion 12b.

The detailed structure of the oil pan 32 will be described with reference to FIGS. The oil pan 32 is preferably made of a casting aluminum alloy such as AC4A-T6,
An oil pan body 44 optionally cast with cast iron or the like
And a thin steel plate mounted on one side of the oil pan main body 44 (an example of the engine 10 shown in FIG. 1 is a rear side of the engine), and a damping steel plate in which an appropriate plastic film or the like is sandwiched between the thin steel plates. And an oil sump 46 made of sheet metal formed into a deep dish shape by press working.

As shown in the plan view of FIG. 3 and the rear view of FIG. 5, the oil pan main body 44 is provided with a peripheral flange 48 over the entire upper surface thereof. Many bolt holes 50 are formed at intervals. By inserting and tightening the mounting bolts 52 (see FIG. 2) into these bolt holes 50, the oil pan main body 44 is attached to the lower surface of the crankcase 12, that is,
Is fixed to the lower end flange of the lower case 12c, and if the lower case 12c is not provided, it is fixed to the lower end flange of the skirt portion 12b.

A shallow plate portion 54 having a substantially cylindrical cross section in the width direction (perpendicular to the crank axis) in FIGS. 4 and 7 is formed in a portion surrounded by the peripheral flange 48. . In the illustrated embodiment, the shallow plate portion 54 includes:
As shown in FIG. 4, both ends in the width direction and the central portion are formed by planes 54a, respectively, and the planes 54a are formed as approximate cylindrical surface walls smoothly connected by partial cylindrical surfaces 54b. However, of course, the entire surface is a cylindrical surface or an elliptical surface,
It may be a single trough-shaped curved wall concave upward, such as a parabolic surface.

In the shallow plate portion 54, a plurality of raised beam portions 56 extending in the width direction at intervals in the longitudinal direction (crank axis direction) are provided side by side. Are formed such that their upper surfaces abut the lower surface of the main bearing cap 26 provided on the crankcase side. The illustrated embodiment shows an oil pan 32 for a four-cylinder engine. In this case, the beam part 56 is a first beam part 56 that abuts on a main bearing cap 26 that supports the vicinity of the front end of the crankshaft 20.
a, a second beam portion 56b abutting the main bearing cap 26 between the first cylinder and the second cylinder, and thereafter similarly between the second and third cylinders, and between the third and fourth cylinders. Four third and fourth beam portions 56c and 56d are provided to abut on the cap 26, respectively.

An upwardly open groove 58 is formed between the front end beam portion 56a and the peripheral flange 48 in front of the beam portion 56a.
Oil and the timing gear case 3 which communicate with the lower opening of the cylinder 4 and lubricate and cool the valve operating mechanism in the cylinder head 14.
A relatively large amount of oil, which has lubricated and cooled rotating members such as gears in 4, has been received. As well shown in FIG. 4 and the cross-sectional view, the lower surface of the shallow dish portion 54 in the longitudinal first half portion of the peripheral flange 48 over the first to third beam portions 56a to 56c has a closed cross section on both sides in the width direction. Tubular spaces 60 and 62 having a structure are provided.

On the other hand, an oil sump mounting flange 64 having a substantially quadrangular planar shape is provided on the lower surface of the rear half portion of the oil pan main body 44, and its front flange portion is slightly forward of the front side wall of the third beam portion 56c. Are located in An outer number of bolt holes 66 are formed in the oil sump mounting flange 64 at small intervals.
By inserting and tightening a mounting bolt 70 (only one of which is illustrated in FIG. 6) between the oil reservoir 46 and the corresponding bolt hole formed in the upper end flange 68 of the oil reservoir 46, the oil reservoir 46 is formed. It is mounted on the lower surface of the oil pan main body 44.

The second and third beam portions 56b and 56
In the portion in contact with the bottom surface of the shallow plate portion 54c, the oil flowing down from the engine component of the first cylinder is guided to the shallow plate portion below the second cylinder, and together with the oil flowing down from the engine component of the second cylinder. The oil flowing down from the first cylinder
Passages 72 and 74 leading to a shallow plate below the cylinder are provided. Further, the bottom wall of the shallow dish below the third cylinder and the bottom wall of the shallow dish below the fourth cylinder have oil holes 76 through which oil flowing into the respective shallow dishes 54 flows down into the oil reservoir 46. 78 are provided.

The groove 58 is interrupted from communicating with the tubular space 62 by a partition wall 80 provided near one side of the oil pan main body 44 in the width direction, and is formed on the other side in the width direction. As shown in the partial cross-sectional view of FIG. 8, the first beam portion 56a communicates with one end of the tubular space portion 60 through an opening 82 provided in an extension of the front side wall of the first beam portion 56a. As shown in the partial sectional view of FIG. 9, the other end of the tubular space 60 is inside one end of a flange portion extending in the width direction of the oil reservoir mounting flange 64 and is formed by the flange 64. It opens to the upper part inside the enclosed oil reservoir 46.

Further, a branch passage 84 communicating with the shallow plate portion 54 between the first and second beam portions 56a and 56b for receiving the oil flowing down from the engine components belonging to the first cylinder is provided in the tubular space 60. And a branch passage 86 communicating with the shallow plate portion 54 between the second and third beam portions 56b and 56c for receiving the oil flowing down from the engine components belonging to the second cylinder. These branch passages 84
And 86, when the amount of oil flowing into the groove portion 58 is excessive in relation to the cross-sectional area of the tubular space portion 60, a part of the oil is diverted into the shallow plate portion 54 to make the oil flow smooth. However, when the tubular space portion 60 has a sufficient sectional area with respect to the amount of oil flowing into the groove portion 58, it can be omitted.

Also, as shown in FIGS. 5 and 10, a corner portion facing the inside of the oil sump 46 beyond the rear end of the tubular space 62, ie, the front end flange of the oil sump mounting flange 64. The inclined hole 8 communicating with the tubular space 62
A connection pipe 90 having one end connected to the oil strainer 42 is inserted into the inclined hole 88 via a seal member such as an O-ring. On the other hand, an opening 92 (see FIG. 3) is provided at the front end of the tubular space 62, that is, at a portion adjacent to the partition wall 80, to which a pipe member communicating with the suction side of the oil pan 40 in the engine 10 is connected. ing.

The oil pan main body 32 is partially cross-sectionally shown in FIG. 2 by means of mounting bolts 96 inserted into two bolt holes 94 provided at the central portions of the first to fourth beam portions 56a to 56d. As shown in FIG. 5, the main bearing cap 26 on the crankcase 12 side is tightly fastened to the main bearing cap 26 inside the pair of tightening bolts 28 in the width direction of the encin. Each one adjacent to 60 and 62
In each of the beam portions 56b to 56d, the tubular space portions 60 and 6
2 are firmly tightened to the main bearing cap 26 by mounting bolts 100 inserted into two bolt holes 98 provided adjacent to each other.

Engine 1 equipped with oil pan 32
During operation 0, the oil that has lubricated and cooled the pistons, piston pins, connecting rods, crankshafts, etc. of the first to fourth cylinders flows down to the shallow plate portion 54 below each cylinder,
Finally, it flows down into the oil reservoir 46. On the other hand, the oil that has lubricated and cooled the valve members, the timing gears, and the like in the cylinder head 14 and the timing gear case 34 flows down into the groove 58, flows through the tubular space 60, and flows into the oil reservoir 46. The oil collected in the oil reservoir 46 passes through the tubular space 62 from the oil strainer 42 and is pumped from the oil pump 40 to each part of the engine 10 that requires lubrication. Reference numeral 102 denotes a plurality of reinforcing vertical ribs arranged on the outer peripheral portion of the oil pan main body 44, and only a part thereof is shown in the cross-sectional views of FIGS. 4 and 7 and the side views of FIG. , And others are not shown in order to avoid excessive congestion of the drawings.

The oil pan 32 is composed of an oil pan main body 44 preferably cast of an aluminum alloy, and an oil sump 46 made of sheet metal and flanged to one side lower surface of the oil pan main body 44. Bread body 44
Is provided with a shallow plate portion 54 formed of a trough-shaped curved wall having a cylindrical shape or an approximate cylindrical shape concave upward, and tubular space portions 60 and 62 formed below both ends in the width direction of the shallow plate portion 54. Therefore, the oil pan main body 44 is fixed to the lower surface of the crankcase 12 so as to effectively suppress the longitudinal and lateral bending and torsional deformation of the crankcase 12 occurring during the operation of the engine 10. It works effectively as

Also, a plurality of beam portions 56a abutting against the main bearing cap 26 on the crankcase 12 side and firmly tightened to the main bearing cap 26 by a large number of mounting bolts 94, 98 on the oil pan main body 44.
Providing the 56d has an advantage that the vibration that the crankcase skirt portion 12b is displaced in the direction perpendicular to the crank axis can be more effectively suppressed, and the operating noise of the engine can be reduced.

An oil passage for supplying the oil in the oil reservoir 46 to the suction side of the oil pump 40 via the oil strainer 42 through one of the tubular spaces 62 juxtaposed on both sides in the width direction of the oil pan main body 44. There is an advantage that the oil piping related to the oil strainer 42 can be omitted and the degree of freedom in designing the arrangement of the oil strainer 42 can be improved. Further, by utilizing the other side 60 of the tubular space as an oil passage for allowing the shallow plate portion 54 to flow into the oil reservoir 46 in cooperation with the oil pan 46, the rigidity of the oil pan main body 44 described above is improved, and the original oil collection of the oil pan is performed. There is an effect that both functions can be compatible.

[0026]

As described above, the oil pan according to the present invention has a peripheral flange fixed to the lower surface of the crankcase of the engine, a shallow plate formed at a portion surrounded by the peripheral flange, and An oil sump mounting flange formed on the lower surface of one side of the shallow dish in the longitudinal direction; and an oil sump mounting flange arranged side by side on both sides in the width direction of the shallow dish. And an oil pan main body having a tubular space portion having a closed cross-sectional structure extending to the inside of the oil pan, and a sheet metal oil sump having a flange formed on an upper peripheral portion thereof fastened to the oil sump mounting flange. One end of the tubular space portion is connected to an oil strainer disposed in the oil reservoir, and the other end is connected to an oil pump of the engine. To It has the advantage that it can function as a reinforcing member that effectively improves the bending and torsional rigidity of the crankcase by being fixed to the lower surface of the engine crankcase, thereby reducing engine operating noise. By utilizing the oil pipe as an oil passage connecting between the strainer and the oil pump, there is an effect that the oil piping is simplified and the arrangement and mounting work of the oil strainer can be facilitated. Further, in the present invention, since the shallow dish portion has a concave gutter-like curved wall on a cylindrical surface or an upper portion approximating the cylindrical surface, it can be manufactured easily at a low cost with a simple structure, In addition, there is an advantage that an oil pan body having excellent bending rigidity in a longitudinal direction and a crankcase can be provided.

Further, in the present invention, the above-mentioned shallow plate portion includes:
A plurality of beam portions are provided between the cylinders of the crankcase and abut on a main bearing cap that supports a crankshaft, and the oil pan body is attached to the main bearing cap by a mounting bolt that passes through the beam portion. The tightening has the effect of improving the lateral bending stiffness of the oil pan main body and thus effectively suppressing vibration displacement in the direction perpendicular to the crank axis of the crankcase skirt.

[Brief description of the drawings]

FIG. 1 is a conceptual side view of a vehicle diesel engine equipped with an oil pan according to the present invention.

FIG. 2 is a partial front view showing a cross section of a main part of the engine shown in FIG. 1;

FIG. 3 is a plan view of the oil pan main body 44 shown in FIG.

FIG. 4 is an enlarged sectional view taken along the line IV-IV in FIG. 3 and viewed in the direction of the arrow.

5 is a rear view of the oil pan main body 44 shown in FIG.

FIG. 6 is a side view of the entire oil pan 32;

FIG. 7 is an enlarged sectional view taken along the line VII-VII in FIG.

FIG. 8 is a partial cross-sectional view taken along the line VIII-VIII in FIG. 3 and viewed in a direction indicated by an arrow.

FIG. 9 is a partial cross-sectional view taken along the line IX-IX of FIGS.

FIG. 10 is a partial cross-sectional view taken along the line XX of FIG. 5 and viewed in the direction of the arrow.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Engine, 12 ... Crankcase, 14 ... Shilling head, 20 ... Crankshaft, 24 ... Lower case or ladder frame, 26 ... Beam part or main bearing cap, 32 ... Oil pan, 36 ... Timing gear case, 40 ... Oil pump, 42 ... oil strainer, 4
4 ... oil pan body, 46 ... oil reservoir, 48 ... peripheral flange on the top surface of the oil pan main body, 54 ... shallow dish portion, 56 ... beam portion, 60 and 62 ... tubular space portion, 64 ... oil reservoir mounting flange.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Katsura Sasaki 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation F-term (reference) 3G015 BB03 BB06 BB09 CA07 DA08 EA04 3G024 AA50 AA60 BA01 BA04 BA11 DA17 EA01 FA02 FA05 FA13 FA14 GA07 GA26 HA01 HA04 HA07

Claims (4)

[Claims] 1. A peripheral flange fixed to a lower surface of a crankcase of an engine, a shallow plate formed in a portion surrounded by the peripheral flange, and a lower surface formed on one side in a longitudinal direction of the shallow plate. An oil sump mounting flange, and a tubular space having a closed cross-sectional structure, which is provided side by side on the width direction of the shallow dish portion and extends from near the other end of the shallow dish portion to the inside of the oil sump mounting flange. An oil pan body having a, and a metal plate-made oil sump fastened to the oil sump mounting flange with a flange formed at an upper end peripheral portion thereof,
An oil pan, wherein one end of the tubular space is connected at one end to an oil strainer disposed in the oil reservoir, and the other end is connected to an oil pump of the engine. 2. The oil pan according to claim 1, wherein the shallow dish portion has a concave gutter-like curved wall which is concave or upwardly similar to a cylindrical surface. 3. A plurality of beam portions provided between said cylinders of said crankcase and abutting on a main bearing cap for supporting a crankshaft are provided on said shallow plate portion, and mounting bolts are inserted through said beam portions. The oil pan according to claim 1 or 2, wherein the oil pan body is tightly fastened to the main bearing cap by means of the above. 4. The other of the tubular space portions is formed as an oil passage for guiding a part of oil flowing down from each portion of the engine to the oil pan main body to the oil reservoir. Item 8. The oil pan according to Item 2.