Oil pan for engine

The integral casting design of the oil pan enhances rigidity, reducing engine noise emissions by minimizing vibrations and maintaining stability during tilting.

JP2026005369APending Publication Date: 2026-01-16KUBOTA CORP
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Patent Information

Application Number
JP2024103647
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-06-27
Publication Date
2026-01-16

AI Technical Summary

Technical Problem

Engine noise is easily emitted due to the low rigidity of sheet metal oil pans, which are prone to vibration.

Method used

The oil pan is designed with a rectangular shape and features an upwardly convex center wall and oil introduction passage walls formed as part of an integral casting, enhancing its rigidity and reducing vibration.

Benefits of technology

The design significantly reduces engine noise emissions by minimizing vibrations, ensuring high rigidity and maintaining stability during tilting.

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Abstract

To provide an oil pan of an engine hardly emitting engine noise.SOLUTION: The oil-pan bottom-wall side 1a includes an upward-convex middle-height 1a side 1aa extending in the front-rear direction at a central portion in the lateral direction of the oil-pan bottom-wall side 1aa, a pair of oil-introduction-passage-wall side 1ab and side 1ab extending in the front-rear direction along both lateral sides of the middle-height 1ab side 1ab, and a pair of oil introduction passages 33 provided in the pair of oil-introduction-passage-wall side and side. 1ab 1ab 1aa.SELECTED DRAWING: Figure 1
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Description

[Technical Field]

[0001] The present invention relates to an engine oil pan, and more particularly to an engine oil pan that is less likely to emit engine noise. [Background technology]

[0002] BACKGROUND ART Conventionally, there are oil pans for engines that are made of sheet metal (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 4-121411 Summary of the Invention [Problem to be solved by the invention]

[0004] <Problem> Engine noise is easily emitted. The sheet metal oil pan of Patent Document 1 has low rigidity, and engine noise such as explosions is easily released via vibration of the oil pan.

[0005] An object of the present invention is to provide an oil pan for an engine that is less likely to emit engine noise. [Means for solving the problem]

[0006] The main features of the present invention are as follows. The oil pan has a rectangular shape in a plan view, and includes an oil pan bottom wall and an oil pan peripheral wall that opens upward. The axial direction of the crankshaft is defined as the front-rear direction, and the width direction of the engine perpendicular to the front-rear direction is defined as the horizontal direction, and the rectangular oil pan has a long side aligned with the front-rear direction and a short side aligned with the horizontal direction, the oil pan bottom wall includes an upwardly convex center wall extending in the front-rear direction at a lateral center portion of the oil pan bottom wall, a pair of oil introduction passage walls extending in the front-rear direction along both lateral sides of the center wall, and a pair of oil introduction passages provided within the pair of oil introduction passage walls, 10. An oil pan for an engine, wherein the middle wall and the pair of oil introduction passage walls are formed as part of an integral casting that forms the oil pan. [Effects of the Invention]

[0007] The present invention has the following advantages. Effect: Engine noise is less likely to be emitted. According to this invention, the mid-height wall and the pair of oil inlet passages are formed as part of the integral casting that makes up the oil pan, which makes the oil pan highly rigid, less prone to vibration, and less likely to emit engine noise such as explosions. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are diagrams illustrating an oil pan of an engine according to an embodiment of the present invention, in which FIG. 1A is a plan view, FIG. 1B is a cross-sectional view taken along line BB in FIG. 1A, FIG. 1C is a cross-sectional view taken along line CC in FIG. 1A, and FIG. 1D is a cross-sectional view taken along line DD in FIG. 1A. [Figure 2] 2A and 2B are diagrams illustrating the oil pan in FIG. 1. FIG. 2A is an exploded perspective view of the oil pan, oil filter, and upper cover of the filter chamber. FIG. 2B is a schematic perspective view of the oil introduction path from the oil introduction passage through the oil filter chamber to the oil pump. [Figure 3] 3(A) is a front view of the oil pan in FIG. 1; FIG. 3(B) is a view taken in the direction of the arrow B in FIG. 3(A); FIG. 3(C) is a view taken in the direction of the arrow C in FIG. 3(A); FIG. 3(D) is a view taken in the direction of the arrow D in FIG. 3(B); and FIG. 3(E) is a view taken in the direction of the arrow E in FIG. 3(A).

[0009] [Figure 4]4A and 4B are diagrams illustrating an exhaust gas treatment case for an engine according to an embodiment of the present invention; FIG. 4A is an oblique view of the exhaust gas treatment case with a support plate attached, viewed diagonally upward from the front, and FIG. 4B is a plan view of the support plate. [Figure 5] 5(A) is a cross-sectional view of the front support stay and its surroundings, FIG. 5(B) is a cross-sectional view of the rear support stay and its surroundings in FIG. 5(A), FIG. 5(C) is a cross-sectional view of the rear support stay and its surroundings, and FIG. 5(D) is a cross-sectional view of the DD line in FIG. 5(C). [Figure 6] 1 is a perspective view of an engine according to an embodiment of the present invention, viewed obliquely downward from the front side; [Figure 7] FIG. 7 is a perspective view of the engine of FIG. 6, seen obliquely downward from the rear side.

[0010] [Figure 8] FIG. 7 is a front view of the engine of FIG. 6. [Figure 9] FIG. 7 is a left side view of the engine of FIG. 6. [Figure 10] FIG. 7 is a right side view of the engine of FIG. 6. [Figure 11] FIG. 7 is a plan view of the engine of FIG. 6. [Figure 12] FIG. 7 is a plan view of the engine of FIG. 6 with the support plate and exhaust gas treatment case removed. [Figure 13] FIG. 7 is a rear view of the engine of FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1 to 13 are diagrams illustrating an engine according to an embodiment of the present invention, and in this embodiment, a vertical in-line multi-cylinder diesel engine will be described.

[0012] As shown in Figure 9, the engine (12) includes a cylinder block (7), a cylinder head (17) attached to the top of the cylinder block (7), a cylinder head cover (14) attached to the top of the cylinder head (17), an engine cooling fan (16) disposed in front of the cylinder block (7), a flywheel housing (13) disposed at the rear of the cylinder block (7), and an oil pan (1) attached to the bottom of the cylinder block (7). The oil pan (1) is fastened to the cylinder block (7) by an oil pan fastening bolt (not shown) inserted from below. As shown in Figures 7 and 13, a flywheel (13a) is accommodated in the flywheel housing (13). An exhaust gas treatment case (15) is disposed above the cylinder head cover (14).

[0013] The engine includes an intake system, a fuel supply system, a combustion system, an exhaust system, and an exhaust gas treatment system. As shown in FIG. 10, the intake system includes an intake manifold (21) mounted on the right side of the cylinder head (17), and an intake throttle (21a) connected to the intake manifold (21). The fuel supply system includes a common rail (22) disposed on the right side of the cylinder head cover (14). The combustion device includes a plurality of cylinders (not shown) arranged in the front-rear direction in a cylinder section (7a) that constitutes the upper half of a cylinder block (7). A crankcase (7b) that constitutes the lower half of the cylinder block (7) accommodates a crankshaft (2) shown in Figure 7. As shown in FIG. 9, the exhaust system includes an exhaust manifold (23) mounted on the left side of the cylinder head (17), and a supercharger (24) mounted above the exhaust manifold (23). The exhaust gas treatment device includes an exhaust gas treatment case (15).

[0014] As shown in Figures 6 and 7, the exhaust gas treatment case (15) of the exhaust gas treatment device includes a DPF housing case (15a) and an SCR housing case (15b) arranged on the right side of the DPF housing case (15a). The DPF housing case (15a) houses a DOC on the upstream exhaust side (rear side) and a DPF on the downstream exhaust side (front side). The SCR housing case (15b) houses an SCR catalyst on the upstream exhaust side (front side) and an ASC on the downstream exhaust side (rear side). The exhaust upstream side (rear side) of the DPF housing case (15a) is connected to an exhaust outlet of an exhaust turbine (24a) of the turbocharger (24) by a heat-resistant flexible pipe (15e). A mixing passage (15c) is interposed between the exhaust downstream side (front side) of the DPF housing case (15a) and the exhaust upstream side (front side) of the SCR housing case (15b), and a urea water injector (not shown) facing the mixing passage (15c) is attached to the DPF housing case (15a).

[0015] DPF stands for diesel particulate filter, and traps PM in exhaust gas. PM is an abbreviation for particulate matter. DOC is an abbreviation for diesel oxidation catalyst, which oxidizes CO (carbon monoxide) and NO (nitrogen monoxide) in exhaust gas. SCR catalyst is an abbreviation for selective catalytic reduction type catalyst. ASC is an abbreviation for ammonia purification oxidation catalyst, which is used to prevent NH3 (ammonia) from slipping.

[0016] In this exhaust gas treatment device, exhaust gas passes through the DOC, DPF, SCR catalyst, and ASC in that order, capturing PM in the exhaust gas in the DPF, and NO (nitric oxide) in the exhaust gas is oxidized by the DOC to produce NO2 (nitrogen dioxide), which is used to continuously oxidize and burn PM accumulated in the DPF at a relatively low temperature. At the same time, urea water injected into the exhaust gas from a urea water injector causes ammonia to be adsorbed on the SCR catalyst, which uses this as a reducing agent to reduce NOx (nitric oxide) in the exhaust, yielding N2 (nitrogen gas) and H2O (water vapor).

[0017] As shown in FIG. 1(A), the oil pan (1) of the engine (12) is rectangular in plan view and includes an oil pan bottom wall (1a) and an oil pan peripheral wall (1b) that is open at the top. The axial length direction of the crankshaft (2) shown in FIG. 7 is the front-rear direction, and the width direction of the engine (12) perpendicular to the front-rear direction is the horizontal direction. As shown in FIG. 1(A), the rectangular oil pan (1) has its long sides aligned along the front-rear direction and its short sides aligned along the horizontal direction. As shown in FIGS. 1(A) to 1(C), the oil pan bottom wall (1a) includes an upwardly convex center wall (1aa) extending in the front-rear direction at the lateral center of the oil pan bottom wall (1a), a pair of oil introduction passage walls (1ab)(1ab) extending in the front-rear direction along both lateral sides of the center wall (1aa), and a pair of oil introduction passages (3)(3) provided in the pair of oil introduction passage walls (1ab)(1ab). As shown in FIGS. 1(B) and 1(C), the middle-height wall 1aa and the pair of oil introduction passage walls 1ab and 1ab are formed as part of an integral casting that constitutes the oil pan 1. 3(A) to (E) show the appearance of the oil pan (1).

[0018] In this engine (12), as shown in FIGS. 1(B) and 1(C), the mid-height wall (1aa) and the pair of oil introduction passage walls (1ab) (1ab) are formed as part of an integral casting that constitutes the oil pan (1). Therefore, the oil pan (1) has high rigidity and is less likely to vibrate, and is less likely to emit engine noise such as explosions.

[0019] As shown in FIG. 1(A), the pair of oil inlets (3a) (3a) of the pair of oil introduction passages (3) (3) are located in the center of the oil pan (1) in the front-rear direction, and as shown in FIG. 1(B), they open to the lower lateral outer sides of the pair of oil introduction passage walls (1ab) (1ab) at a position facing the inner bottom of the oil pan (1).

[0020] According to this engine (12), when the engine is tilted in the longitudinal or lateral direction, air is hardly drawn through the oil inlets (3a) of the pair of oil introduction passages (3), (3), and the engine has high tilting performance.

[0021] As shown in FIG. 2(B), the oil pan (1) includes a filter chamber (5) that connects the pair of oil introduction passages (3), (3) with the oil pump (4). As shown in FIG. 2(A), an oil filter (6) is housed in the filter chamber (5). The arrows (25) in Figures 2(A) and 2(B) indicate the flow of oil.

[0022] According to this engine (12), there is no need to provide an oil filter at the oil inlet (3a) shown in FIGS. 1(B) and 2(B), so that a large oil passage area can be ensured at the pair of oil inlets (3a) and (3a).

[0023] As shown in FIGS. 1(A) and 2(A), the filter chamber (5) is surrounded by a filter chamber peripheral wall (5a). The filter chamber peripheral wall (5a) protrudes upward from the mid-height wall (1aa) and the pair of oil introduction passage walls (1ab) (1ab) along the oil pan peripheral wall (1b) at one end side of the oil pan bottom wall (1a) in the front-to-rear direction, and is formed as part of an integral casting that constitutes the oil pan (1).

[0024] According to this engine, the filter chamber peripheral wall (5a) can increase the rigidity of the oil pan (1).

[0025] As shown in FIG. 2(A), the upper side of the filter chamber (5) is closed by an upper cover (5b), and the oil filter (6) is formed in a flat shape. As shown in FIG. 1(A), the filter chamber peripheral wall (5a) is formed in a horizontally elongated rectangular shape in a plan view, and as shown in FIG. 2(A), it has an intermediate step surface (5aa) and an upper end surface (5ab) at the intermediate position and the upper end position in the height direction of the filter chamber (5). The peripheral edge portion (6a) of the oil filter (6) is placed and fixed on the intermediate step surface (5aa), and the peripheral edge portion (5ba) of the upper cover (5b) is placed and fixed on the upper end surface (5ab).

[0026] According to this engine (12), the oil filter (6) can be easily installed in the filter chamber (5). A gasket (5c) having a horizontally elongated rectangular shape is sandwiched between the upper end surface (5ab) of the filter chamber (5) and the peripheral edge (5ba) of the upper cover (5b) to seal the gap therebetween.

[0027] As shown in FIGS. 6 and 7, the engine (12) is provided with a support structure for the exhaust gas treatment case of the engine, which supports the exhaust gas treatment case (15) above the cylinder head cover (14) in a vibration-isolating manner. The axial length direction of the crankshaft (2) is the front-rear direction, and in the front-rear direction, the engine cooling fan (16) side is the front side and the flywheel housing (13) side is the rear side. The exhaust gas treatment case (15) is provided with a front support stay (18) attached to the cylinder head (17) and a rear support stay (19) attached to the flywheel housing (13), and is supported in a vibration-damping manner by front vibration-damping rubber (18a) placed on the front support stay (18) shown in Figures 5(A) and (B) and rear vibration-damping rubber (19a) (19a) placed on the rear support stay (19) shown in Figures 5(C) and (D). As shown in Figure 8, when viewed in the front-rear direction, the front support stay (18) is arranged within a fan rotation area (16b) surrounded by a rotation path (16a) of the outer peripheral edge of the axial flow engine cooling fan (16).

[0028] As shown in Figures 6 and 7, in this engine (12), the support for the exhaust gas treatment case (15) is a front support stay (18) attached to the cylinder head (17) and a rear support stay (19) attached to the flywheel housing (13), which makes it easy to perform maintenance on engine parts from the side of the engine.

[0029] Furthermore, as shown in Figures 6 and 7, in this engine (12), the support for the exhaust gas treatment case (15) is a front support stay (18) attached to the cylinder head (17) and a rear support stay (19) attached to the flywheel housing (13), so that the support for the exhaust gas treatment case (15) can be made smaller.

[0030] Furthermore, as shown in Figure 8, in this engine (12), the front support stay (18) is arranged within a fan rotation area (16b) surrounded by the rotation locus (16a) of the outer periphery of the axial flow engine cooling fan (16) when viewed in the front-to-rear direction. Therefore, heat transferred from the cylinder head (17) to the front support stay (18) is dissipated into the cooling air of the engine cooling fan (16) and is not easily transferred to the front vibration isolation rubber (18a) shown in Figures 5(A) and (B), thereby suppressing thermal deterioration of the front vibration isolation rubber (18a).

[0031] As shown in Figure 4(A), a support plate (20) is attached to the underside of the exhaust gas treatment case (15), and as shown in Figures 5(A) and 5(C), the support plate (20) is supported by the front vibration-isolating rubber (18a) and the rear vibration-isolating rubber (19a)(19a).

[0032] According to this engine (12), the vibration-proof support suppresses vibration of the exhaust gas treatment case (15) shown in Figure 4(A), and the exhaust gas treatment case (15) and the exhaust gas treatment device housed therein are less likely to be damaged by vibration of the engine (12).

[0033] The width direction of the engine, which is perpendicular to the longitudinal direction, is defined as the lateral direction. As shown in FIG. 8, the front support stay (18) is disposed in the front of the engine (12) at the lateral center of the engine (12), and as shown in FIG. 5(A), a single front rubber support seat (18b) is placed on the front support stay (18), and the front vibration-isolating rubber (18a) is placed on the front rubber support seat (18b).

[0034] As shown in FIG. 7, the rear support stay (19) is disposed on the rear side of the engine (12), and as shown in FIG. 5(C), a pair of left and right rear rubber receiving seats (19b)(19b) are placed on the rear support stay (19), and a pair of left and right rear vibration-isolating rubbers (19a)(19a) are placed on the pair of left and right rear rubber receiving seats (19b)(19b).

[0035] According to this engine (12), the exhaust gas treatment case (15) is stably supported by three points, that is, the single front vibration isolating rubber (18a) and the pair of left and right rear rubber receiving seats (19b), (19b).

[0036] As shown in Figures 5(A) and (B), the single front rubber support seat (18b) has a cylindrical front rubber support seat peripheral wall (18c) that surrounds the front vibration-damping rubber (18a), and as shown in Figures 5(C) and (D), the pair of left and right rear rubber support seats (19b)(19b) have a pair of left and right cylindrical rear rubber support seat peripheral walls (19c)(19c) that surround the pair of left and right rear vibration-damping rubbers (19a)(19a), respectively.

[0037] As shown in Figures 5(A) and 5(B), the engine (12) is provided with a single front semicircular arc stopper (18d) on the underside of the support plate (20), and as shown in Figures 5(C) and 5(D), a pair of rear quarter-circular arc stoppers (19d) (19d) on the left and right. As shown in FIG. 5(B), the single front semicircular stopper (18d) faces the front rubber seat peripheral wall (18c) from the rear side, with a semicircular gap (18e) formed between them. As shown in Figure 5 (D), a space (19g) is provided between the pair of left and right rear rubber seat peripheral walls (19c) (19c), and the pair of left and right rear quarter-circular stoppers (19d) (19d) hold quarter-circular gaps (19e) (19e) in the pair of left and right rear rubber seat peripheral walls (19c) (19c) and face the space (19g) from the diagonally front side.

[0038] With this engine (12), the vibration amplitude of the exhaust gas treatment case (15) can be limited all around with a small number of stoppers, consisting of a single front semicircular arc stopper (18d) and a pair of rear quarter-circular arc stoppers (19d) (19d).

[0039] As shown in Figures 5(A) and 5(C), the support plate (20) maintains upper and lower gaps (18f) and (19f) between the single front rubber seat peripheral wall (18c) and the pair of rear rubber seat peripheral walls (19c) and (19c), respectively, and faces the upper side.

[0040] According to this engine (12), when the exhaust gas treatment case (15) descends, the support plate (20) is received by the front rubber seat peripheral wall (18c) and the rear rubber seat peripheral wall (19c) (19c), thereby stopping the descent of the exhaust gas treatment case (15) and preventing the support plate (20) from colliding with the cylinder head cover (14).

[0041] As shown in Figure 5(A), the front vibration-damping rubber (18a) has a pair of upper and lower front rubber portions (18aa) (18aa), and as shown in Figure 4(B), the support plate (20) has a front clamping portion (20a), and as shown in Figure 5(A), the front clamping portion (20a) is supported by being clamped from above and below by the pair of upper and lower front rubber portions (18aa) (18aa).

[0042] According to this engine (12), when the exhaust gas treatment case (15) vibrates up and down, the front clamping portion (20a) is received by the pair of upper and lower front rubber portions (18aa) (18aa), so that the front clamping portion (20a) is less likely to be damaged by the vibrations.

[0043] As shown in Figure 5(C), the pair of left and right rear vibration-damping rubbers (19a)(19a) each have a pair of upper and lower rear rubber portions (19aa)(19aa), and as shown in Figure 4(B), the support plate (20) has a pair of left and right rear clamping portions (20b), and as shown in Figure 5(C), the pair of left and right rear clamping portions (20b) are supported by being clamped from above and below by the pair of upper and lower rear rubber portions (19aa)(19aa).

[0044] According to this engine (12), when the exhaust gas treatment case (15) vibrates up and down, the rear clamping portion (20b) is received by the pair of upper and lower rear rubber portions (19aa) (19aa), and therefore the rear clamping portion (20b) is less likely to be damaged by the vibrations.

[0045] As shown in FIG. 4(B), the support plate (20) has a front mounting plate portion (20c) and a rear mounting plate portion (20d) to be attached to the exhaust gas treatment case (15) between the front clamping portion (20a) and a pair of left and right rear clamping portions (20b)(20b), and has a pair of left and right openings (20e)(20e) between the front mounting plate portion (20c) and the rear mounting plate portion (20d). The support plate 20 is made of casting and has a pair of openings 20e, 20e on the left and right to reduce its weight. [Explanation of symbols]

[0046] (1)...oil pan, (1a)...oil pan bottom wall, (1aa)...mid-height wall, (1ab)...oil introduction passage wall, (1b)...oil pan peripheral wall, (2)...crankshaft, (3)...oil introduction passage, (3a)...oil inlet, (4)...oil pump, (5)...filter chamber, (5a)...filter chamber peripheral wall, (5aa)...intermediate step surface, (5ab)...upper end surface, (5b)...top cover, (5ba)...peripheral portion, (6)...oil filter, (6a)...peripheral portion, (7)...cylinder block, (12)...engine, (13)...flywheel housing.

Claims

1. The oil pan has a rectangular shape in a plan view, and includes an oil pan bottom wall and an oil pan peripheral wall that opens upward. The axial direction of the crankshaft is defined as the front-rear direction, and the width direction of the engine perpendicular to the front-rear direction is defined as the horizontal direction, and the rectangular oil pan has a long side aligned with the front-rear direction and a short side aligned with the horizontal direction, the oil pan bottom wall includes an upwardly convex center wall extending in the front-rear direction at a lateral center portion of the oil pan bottom wall, a pair of oil introduction passage walls extending in the front-rear direction along both lateral sides of the center wall, and a pair of oil introduction passages provided within the pair of oil introduction passage walls, 10. An oil pan for an engine, wherein the middle wall and the pair of oil introduction passage walls are formed as part of an integral casting that forms the oil pan.

2. 2. The engine oil pan according to claim 1, an oil pan for an engine, characterized in that a pair of oil inlets of the pair of oil introduction passages are located in the center of the oil pan in the fore-and-aft direction, and open to the outer lateral sides of the lower part of the pair of oil introduction passage walls at a position facing the inner bottom of the oil pan.

3. 3. The engine oil pan according to claim 2, a filter chamber that connects the pair of oil introduction passages with an oil pump; An oil pan for an engine, wherein an oil filter is accommodated in the filter chamber.

4. 4. The engine oil pan according to claim 3, The filter chamber is surrounded by a filter chamber peripheral wall, an oil pan for an engine, wherein the filter chamber peripheral wall protrudes upward from the mid-height wall and the pair of oil introduction passage walls along the oil pan peripheral wall at one end side of the oil pan bottom wall in the front-to-rear direction, and is formed as part of an integral casting that constitutes the oil pan.

5. 5. The engine oil pan according to claim 4, The upper side of the filter chamber is closed by an upper cover, and the oil filter is formed in a flat shape. the filter chamber peripheral wall is formed in a horizontally elongated rectangular shape in a plan view, and has an intermediate step surface and an upper end surface at an intermediate position and an upper end position in a height direction of the filter chamber, an oil pan for an engine, wherein a peripheral portion of the oil filter is placed and fixed on the intermediate stepped surface, and a peripheral portion of the upper lid is placed and fixed on the upper end surface.

Citation Information

Patent Citations

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