Oil pan of an internal combustion engine

Abstract

To provide an oil pan for an internal combustion engine that can effectively reduce film vibration that is generated in the oil pan with a simpler and lighter structure.SOLUTION: An oil pan 30 for an internal combustion engine includes: a recessed oil storage part 34; a pipe 36 of which one end is installed in the oil storage part 34; and a pipe holding part 37 installed to an antinode part to be an antinode of film vibration (film vibration region M1, M2) that is generated in the oil pan 30 to hold the pipe 36 in the oil pan 30.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an oil pan of an internal combustion engine.

Background Art

[0002] A general internal combustion engine mounted on a vehicle or the like has a cylinder head and a cylinder block (including a crankcase), and an oil pan is provided below the cylinder block (the lowermost part of the internal combustion engine). The oil pan is formed in a thin and deep dish shape with a recessed oil storage part at the deepest part, and oil is stored in the oil storage part. The oil stored in the oil storage part is pumped up by an oil pump through a strainer, which is a filter, and a pipe, and is used for lubricating and cooling various parts of the internal combustion engine, and then returned to the oil pan.

[0003] In recent years, in order to improve fuel efficiency and the like, the weight reduction of internal combustion engines has been promoted, and the wall thickness of the oil pan tends to be further reduced. Even if the wall thickness is not a problem from the viewpoint of rigidity, since the bottom surface of the oil pan has a relatively large area, membrane vibration may occur on the bottom surface of the oil pan due to the vibration of the internal combustion engine in the operating state. When membrane vibration occurs on the bottom surface of the oil pan, unpleasant noise may occur, and reduction of the membrane vibration is desired.

[0004] For example, Patent Document 1 discloses an internal combustion engine in which a large block portion is integrally formed on the front wall, which is one of the side surfaces of the oil pan, an oil suction port is formed in the block portion, a large strainer is made unnecessary, and the oil suction mechanism is made compact. Since the rigidity of the oil pan is improved by the block portion and the like, there is an effect of suppressing vibration and noise.

[0005] Furthermore, Patent Document 2 discloses an internal combustion engine in which an oil pump is fixed to the lower surface of a cylinder block, an oil pan is provided below the cylinder block so as to cover the oil pump, and a lower boss is erected from the bottom surface of the oil pan so as to bring the oil pump into contact with the lower boss. With this configuration, the lower boss erected on the oil pan is pressed down by the oil pump, improving the vibration suppression effect on the bottom surface of the oil pan. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-123463 [Patent Document 2] Japanese Patent Publication No. 2019-027380 [Overview of the project] [Problems that the invention aims to solve]

[0007] In the internal combustion engine described in Patent Document 1, a large block section is integrally molded with the front wall of the oil pan, which is undesirable because it significantly increases the weight of the oil pan. Furthermore, although the block section is integrated with the bottom surface near the front wall of the oil pan, a large area remains on the bottom surface of the oil pan, and there is a possibility that film vibration may occur on the bottom surface of the oil pan in areas where the block section is not provided.

[0008] Furthermore, the internal combustion engine described in Patent Document 2 has a somewhat complex structure in order to bring the oil pump and the lower boss into contact, which is undesirable because it imposes restrictions on the shape of the oil pump, the shape of the oil pan, and the position where the lower boss is erected, preventing a free design. In addition, there is a possibility that film vibration may occur on the bottom surface of the oil pan at a location different from the erected lower boss.

[0009] This invention was conceived in view of the above points, and aims to provide an oil pan for an internal combustion engine that can effectively reduce film vibrations generated in the oil pan with a simpler and lighter structure. [Means for solving the problem]

[0010] To solve the above problems, the first invention is an oil pan for an internal combustion engine, comprising: a recessed oil reservoir; a pipe with one end installed in the oil reservoir; and a pipe holding portion provided on the antinode of the membrane vibration occurring in the oil pan to hold the pipe within the oil pan.

[0011] Next, the second invention is an oil pan for an internal combustion engine according to the first invention, wherein the pipe holding portion is provided in the central region of the antinode, which is at or near the center of the antinode of the membrane vibration.

[0012] Next, the third invention is an oil pan for an internal combustion engine according to the first or second invention, wherein the body of the oil pan is provided with ribs that pass through the position where the pipe holding portion is provided. [Effects of the Invention]

[0013] According to the first invention, by providing a pipe holder that holds the pipe at the antinode of the membrane vibration occurring in the oil pan, the mass of the antinode of the membrane vibration is increased (increase in the mass of the pipe holder + the mass of the pipe + the mass of the oil). This makes it possible to accurately and effectively reduce the membrane vibration occurring in the oil pan with a simpler configuration. Furthermore, although the position of the pipe holder has been changed to a more appropriate position compared to conventional oil pans, no new members have been added, so the mass of the oil pan does not increase significantly. The position and magnitude of the membrane vibration occurring in the oil pan can be determined by simulations such as eigenvalue calculations using a computer, or by experiments using an actual oil pan.

[0014] According to the second invention, the amplitude of membrane vibrations generated in the oil pan can be reduced more effectively. Furthermore, the mass of the oil pan does not increase significantly.

[0015] According to the third invention, the film vibration generated in the oil pan can be reduced more effectively. Further, the ribs provided on the oil pan are only at the minimum necessary locations, and even if the mass of the oil pan increases, it is only due to the ribs.

Brief Description of the Drawings

[0016] [Figure 1] It is a view for explaining the schematic configuration of the internal combustion engine and the position of the oil pan in the internal combustion engine. [Figure 2] It is a view of the oil pan seen from above. [Figure 3] It is the III-III cross-section in FIG. 2. [Figure 4] It is a view of the oil pan seen from below. [Figure 5] It is the V-V cross-section in FIG. 2. [Figure 6] It is a perspective view showing an example of the appearance of the oil holding portion. [Figure 7] It is a view of the oil pan seen from above and is a view for explaining an example in which ribs are provided so as to pass through the oil holding portion.

Embodiments for Carrying Out the Invention

[0017] Hereinafter, the oil pan 30 of the internal combustion engine 1 of the present invention will be described with reference to the drawings. When the X-axis, Y-axis, and Z-axis are shown in the drawings, the X-axis, Y-axis, and Z-axis are orthogonal to each other, the Z-axis direction indicates the direction upward in the vertical direction, and the X-axis direction and Y-axis direction indicate the horizontal direction.

[0018] <Schematic Configuration of Internal Combustion Engine 1 (FIG. 1) and Structure of Oil Pan 30 (FIGS. 1 to 6)> As shown in FIG. 1, the internal combustion engine 1 includes a cylinder head 10 and a cylinder block 20 (including a crankcase), and an oil pan 30 is attached below the cylinder block 20. Although not shown, an oil pump for pumping up the oil stored in the oil pan 30 is provided in the cylinder block 20.

[0019] The oil pan 30 is disposed at a position lower than the cylinder head 10 and the cylinder block 20, and is disposed at the lowermost part of the internal combustion engine 1. As shown in FIG. 3, the oil pan 30 has an oil storage portion 34 recessed to store oil, a pipe 36 having one end installed in the oil storage portion 34, a pipe holding portion 37 for holding the pipe 36 in the oil pan 30, and the like. The oil storage portion 34 is at the lowest position in the oil pan 30, and oil is stored therein.

[0020] One end of the pipe 36 is connected to a strainer 35 (filter) and is submerged (immersed) in the oil A stored in the oil storage portion 34 together with the strainer 35. The other end of the pipe 36 is connected to an oil pump (not shown). The oil A stored in the oil storage portion 34 is pumped up by the oil pump through the strainer 35 and the pipe 36, used for lubricating and cooling various parts of the internal combustion engine, and then returned to the oil pan 30. The material of the pipe 36 is, for example, metal.

[0021] The oil pan 30 has a flange portion 31 fixed to the cylinder block 20, side surfaces 32a, 32b, 32c, 32d on the front, rear, left, and right, and a bottom surface 33, and an oil storage portion 34 is formed in a part of the bottom surface 33.

[0022] As shown in FIGS. 5 and 6, the pipe holding portion 37 has a base portion 37a, a bracket 37b, a fastening portion 37c, and the like. The base portion 37a is a block-shaped member fixed to the bottom surface 33 of the oil pan 30 as shown in FIG. 5. The bracket 37b is a plate-shaped elastic member that covers the outer peripheral surface of the pipe 36, holds the pipe 36, and is fixed to the base portion 37a. The fastening portion 37c is a member for fixing the bracket 37b to the base portion 37a, and is, for example, a bolt. The materials of the base portion 37a, the bracket 37b, and the fastening portion 37c are, for example, metal.

[0023] The oil pan 30 is made of metal, for example, and in recent years, it has been made thinner to reduce weight. Even though the thin wall provides sufficient rigidity from a rigidity standpoint, the bottom surface 33 of the oil pan 30 has a relatively large area, so there is a possibility that membrane vibrations will occur at various points on the oil pan 30 due to vibrations from the internal combustion engine 1, etc. In this embodiment, by setting the position of the pipe holding part 37 fixed to the oil pan 30 to an appropriate position in the following procedure (1) to (4), membrane vibrations generated in the oil pan 30 are effectively reduced with a simpler and lighter structure.

[0024] <Procedure (1): Determine the position and amplitude of the membrane vibration occurring in the oil pan 30> First, in procedure (1), before determining the position of the pipe holding portion 37 on the bottom surface 33 of the oil pan 30, the position and amplitude of the membrane vibration occurring in the oil pan 30 (oil pan 30 without the pipe holding portion 37 attached) are determined as follows. As examples of determining the position and amplitude of membrane vibration, (Method 1) and (Method 2) are given below, but other methods may be used.

[0025] (Method 1) Using computer simulations such as eigenvalue calculations, input the material and shape of the oil pan 30 and check the magnitude of the "displacement" at each point of the oil pan. The points where displacement occurs are the points where membrane vibration occurs, and the magnitude of the displacement is the amplitude of the membrane vibration.

[0026] (Method 2) The oil pan 30 is actually fabricated, and the location of membrane vibration and the amplitude of membrane vibration are measured in experiments such as vibration tests.

[0027] <Step (2): Determine the central position of the antinode of the large-amplitude membrane vibration that needs to be addressed.> For example, the location and amplitude of membrane vibration are determined using (Method 1) above. The determined location of membrane vibration may not be limited to one location, but may be multiple locations. Since there is no need to deal with membrane vibrations with small amplitudes, membrane vibrations with amplitudes larger than a predetermined amplitude are extracted. Then, the region in which membrane vibrations with amplitudes larger than the predetermined amplitude occur and the central position of the antinode (antinode) of that membrane vibration are determined. The central position of the antinode of a membrane vibration is the location with the largest amplitude (the location with the largest displacement) within the region of that membrane vibration.

[0028] In the examples shown in Figures 2 to 4, membrane vibrations with amplitudes larger than a predetermined amplitude occur in two locations: membrane vibration region M1 and membrane vibration region M2. Furthermore, in the examples in Figures 2 to 4, the central position of the abdomen where the largest amplitude occurs within membrane vibration region M1 is M1c, and the central position of the abdomen where the largest amplitude occurs within membrane vibration region M2 is M2c.

[0029] <Procedure (3): Determine the mounting position of the pipe holder 37> If the central position of the belly of the membrane vibration region to be addressed is known, then the mounting position of the pipe holder 37 should be at that central position. However, as shown in Figure 3, the bottom surface 33 of the oil pan 30 may have various curved sections, and the central position of the belly of the determined membrane vibration region may be a place where it is difficult to fix the pipe holder 37. As for the mounting position of the pipe holder 37, the central position of the belly of the membrane vibration region is the most effective for reducing membrane vibration, but a central region near the center of the belly may also be acceptable. In such cases, the mounting position should be within the central region near the center of the belly, as close to the center of the belly as possible, and a position where it is easy to attach the pipe holder 37.

[0030] <Procedure (4): Fix the pipe holder 37 in the mounting position and hold the pipe 36.> After determining the mounting position of the pipe holder 37, the pipe holder 37 is attached to that mounting position. If the oil pan 30 and the base portion 37a are made of metal or resin, and the oil pan 30 and the base portion 37a are separate components, they are fixed by welding or other joining methods. If the oil pan 30 is manufactured by die-casting, after determining the mounting position of the pipe holder 37, the oil pan 30 and the base portion 37a may be designed to form a single molded product.

[0031] Then, as shown in Figures 2 and 3, a strainer 35 (filter) is attached to one end of the pipe 36, and the strainer 35 and one end of the pipe 36 are placed in the oil reservoir 34 and submerged in oil A. The pipe 36 is then deformed so that it passes through the pipe holder 37 and attached to the pipe holder 37. The other end of the pipe 36 is then connected to an oil pump (not shown).

[0032] Furthermore, after determining the mounting position of the pipe holder 37 on the oil pan 30, the pipe holder 37 is attached to that mounting position, and then the pipe 36 is attached. The simulation, such as the eigenvalue calculation described above, can be performed again to confirm the effect of reducing membrane vibration.

[0033] <Other structures of the oil pan (Figure 7)> Figure 7 also shows an example of an oil pan 30a with a different structure. The oil pan 30a shown in the example in Figure 7 differs from the oil pan 30 shown in Figure 2 in that ribs 41x, 42x, 41y, and 42y are added to the bottom surface 33 and the sides 32a, 32b, 32c, and 32d of the oil pan. Alternatively, the ribs 41x, 42x, 41y, and 42y may be provided only on the bottom surface 33 of the oil pan.

[0034] As shown in Figure 7, the ribs 41x along the X-axis and ribs 41y along the Y-axis are provided so as to pass through the pipe holding portion 37 located in the central region near the central position M1c of the belly of the membrane vibration region M1. Similarly, the ribs 42x along the X-axis and ribs 42y along the Y-axis are provided so as to pass through the pipe holding portion 37 located in the central region near the central position M2c of the belly of the membrane vibration region M2.

[0035] In the example shown in Figure 7, ribs 41x and 41y are provided in the membrane vibration region M1, but it is also possible to provide only one of ribs 41x or 41y. Similarly, in the example shown in Figure 7, ribs 42x and 42y are provided in the membrane vibration region M2, but it is also possible to provide only one of ribs 42x or 42y.

[0036] <Effects> In the oil pan 30 described above, the combined mass of the pipe holder 37, the pipe 36, and the oil flowing through the pipe 36 rests at the antinodes of the membrane vibration regions M1 and M2 in the membrane vibration occurring in the oil pan 30, thereby suppressing the membrane vibration and effectively reducing it. Furthermore, since only the position of the originally installed pipe holder 37 has been changed, no new parts have been added, and the mass of the oil pan 30 has hardly increased.

[0037] Furthermore, since the location and magnitude of membrane vibrations will be almost the same for mass-produced oil pans of the same type, it is not necessary to check the location and magnitude of membrane vibrations for every single oil pan.

[0038] Furthermore, in the oil pan 30a shown in Figure 7, which has ribs 41x, 42x, 41y, and 42y added, the mass of the pipe holder 37 and other components is placed in the central region of the antinodes of the membrane vibration, and reinforcement is added by the ribs, so membrane vibration can be reduced even more effectively. Also, the increase in mass of the oil pan 30a is only due to the ribs, so only a small increase in mass is required.

[0039] The oil pans 30 and 30a of the internal combustion engine of the present invention are not limited to the configuration, structure, shape, appearance, etc., described in this embodiment, and various modifications, additions, and deletions are possible without altering the essence of the present invention.

[0040] The materials of the oil pan 30, 30a, pipe 36, and pipe holder 37 are not particularly limited, and metals, resins, etc., can be used. [Explanation of symbols]

[0041] 1. Internal combustion engine 10 Cylinder head 20 Cylinder Block 30, 30a oil pan 31 Flange section 32a, 32b, 32c, 32d side 33 Bottom 34 Oil reservoir 35 Strainer 36 pipes 37 Pipe holding section 37a Base section 37b Bracket 37c Fastening section 41x, 41y rib 42x, 42y rib A Oil M1, M2 membrane vibration region M1c, M2c: Central abdominal location

Claims

1. It is an oil pan for an internal combustion engine. A recessed oil reservoir, A pipe with one end installed inside the oil reservoir, A pipe holding portion is provided at the antinode of the membrane vibration occurring in the oil pan, and holds the pipe within the oil pan, It has, The aforementioned oil pan is The deep bottom surface which is the bottom surface of the oil reservoir, A shallow bottom surface which is shallower than the deep bottom surface and wider than the deep bottom surface, It has, The aforementioned pipe holding portion is The shallow bottom surface is provided on the aforementioned surface Oil pan for an internal combustion engine.

2. An oil pan for an internal combustion engine according to claim 1, The pipe holding portion is provided in the central region of the ventral region, which is at or near the center of the antinode of the membrane vibration. Oil pan for an internal combustion engine.

3. An oil pan for an internal combustion engine according to claim 1 or 2, The abdominal portion is provided with ribs that pass through the position where the pipe holding portion is provided. Oil pan for an internal combustion engine.

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