INTERNAL COMBUSTION ENGINE

Abstract

An internal combustion engine includes a cylinder block, a coolant pump, an oil cooler, an oil pan, and a coolant channel. The coolant channel is a channel passing through the oil pan and configured to supply a coolant to the oil cooler. The oil pan includes an annular first oil pan mounted on the cylinder block and a second oil pan mounted on the first oil pan. The coolant channel includes a coolant pipe located closer to the second oil pan than the middle in an up-down direction of the first oil pan. The coolant pipe extends in a reference direction crossing the up-down direction. Both a first end and a second end of the coolant pipe are fixed to a side wall of the first oil pan.

Claims

1. An internal combustion engine comprising: a cylinder block; a coolant pump configured to discharge a coolant, the coolant pump being mounted on the cylinder block; an oil cooler configured to cool oil using the coolant discharged from the coolant pump, the oil cooler being installed on an opposite side of the cylinder block from the coolant pump; an oil pan located between the coolant pump and the oil cooler and mounted on a lower part of the cylinder block; and a coolant channel configured to supply to the oil cooler the coolant discharged from the coolant pump, the coolant channel passing through the oil pan, wherein: the oil pan includes an annular first oil pan and a second oil pan, the first oil pan being mounted on the cylinder block, and the second oil pan being located on an opposite side of the first oil pan from the cylinder block and mounted on the first oil pan; the coolant channel includes a coolant pipe located closer to the second oil pan than a middle in an up-down direction of the first oil pan; and the coolant pipe extends in a prescribed direction crossing the up-down direction, and both a first end and a second end of the coolant pipe are fixed to a side wall of the first oil pan, the up-down direction being a direction in which the oil pan and the cylinder block are arranged.

2. The internal combustion engine according to claim 1, wherein the coolant pipe is installed in a flow path of the oil that flows into the oil pan.

3. The internal combustion engine according to claim 1, wherein the coolant pipe is installed at such a position that the coolant pipe contacts the oil stored in the oil pan.

4. The internal combustion engine according to claim 1, wherein the coolant pipe is disposed in a middle region in a width direction of the first oil pan, the width direction being a direction perpendicular to both of the up-down direction and the prescribed direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Features, advantages, and technical and industrial significance of exemplary embodiments of the disclosure will be described below with reference to the accompanying drawings, in which like signs denote like elements, and wherein:

[0013] FIG. 1 is a schematic diagram illustrating an internal combustion engine according to an embodiment;

[0014] FIG. 2 is a schematic view illustrating an internal structure of an oil pan included in the internal combustion engine of FIG. 1;

[0015] FIG. 3 is a schematic view illustrating an internal structure of an oil pan included in the internal combustion engine of FIG. 1;

[0016] FIG. 4 is a schematic view showing an outline of an inner configuration of an oil pan included in an internal combustion engine according to a modification; and

[0017] FIG. 5 is a schematic diagram illustrating an outline of an internal structure of an oil pan included in an internal combustion engine according to a modified example.

DETAILED DESCRIPTION OF EMBODIMENTS

[0018] Hereinafter, an embodiment of an internal combustion engine will be described with reference to FIGS. 1 to 3.

Overall Configuration of the Internal Combustion Engine

As shown in FIG. 1, the internal combustion engine 10 includes a cylinder block 11, a cylinder head 13, and an oil pan 15. A plurality of cylinders 111 is formed in the cylinder block 11. A piston is accommodated in the plurality of cylinders 111. A direction in which the plurality of cylinders 111 is arranged is referred to as a cylinder arrangement direction. A direction in which the piston reciprocates in the cylinder 111 is referred to as a up-down direction X. The up-down direction X is substantially perpendicular to the cylinder arrangement direction. In the up-down direction X, a moving direction in which the piston approaches the cylinder head 13 is referred to as an upward direction X1, and a direction opposite to the upward direction X1 is referred to as a downward direction X2.

[0019] The cylinder head 13 is mounted on an upper part of the cylinder block 11. The oil pan 15 is mounted on a lower part of the cylinder block 11. That is, the cylinder head 13, the cylinder block 11, and the oil pan 15 are arranged in the up-down direction X.

[0020] As shown in FIGS. 1 and 2, oil circulating in the internal combustion engine 10 is stored in the oil pan 15. The oil pan 15 includes an annular first oil pan 16 mounted on the cylinder block 11, and a second oil pan 17 mounted on a lower part of the first oil pan 16. The opening of the first oil pan 16 in the upward direction X1 is closed by the cylinder block 11. The second oil pan 17 is mounted on the first oil pan 16 so as to close the opening in the downward direction X2 of the first oil pan 16. The second oil pan 17 includes a cylindrical portion 171 and a bottom wall 172 that closes an opening in the downward direction X2 of the cylindrical portion 171.

[0021] A crankshaft 19, which is an output shaft of the internal combustion engine 10, is provided in the first oil pan 16. For example, in the first oil pan 16, the crankshaft 19 is disposed in the upward direction X1 with respect to the intermediate position in the up-down direction X. That is, the first oil pan 16 also functions as a crankcase.

[0022] The internal combustion engine 10 further includes a coolant pump 21, an oil cooler 23, and a coolant channel 25. The coolant pump 21 discharges coolant circulating in the internal combustion engine 10. The coolant pump 21 is mounted on the cylinder block 11. A direction substantially perpendicular to the cylinder arrangement direction and the up-down direction X is referred to as a reference direction Y. At this time, the coolant pump 21 is mounted on one side in the reference direction Y of the cylinder block 11.

[0023] The oil cooler 23 is installed on the opposite side of the cylinder block 11 from the coolant pump 21. That is, the oil pan 15 is positioned between the oil cooler 23 and the coolant pump 21. The oil cooler 23 cools the oil by using the coolant discharged from the coolant pump 21.

[0024] The coolant channel 25 is a channel for supplying the coolant discharged from the coolant pump 21 to the oil cooler 23. The coolant channel 25 is configured to pass through the oil pan 15. Specifically, as shown in FIG. 2, the coolant channel 25 includes a coolant pipe 26 located closer to the second oil pan 17 than the middle in the up-down direction X of the first oil pan 16. A long dashed double-short dashed line FG in FIG. 2 is an imaginary line indicating the middle in the up-down direction X of the first oil pan 16. The coolant pipe 26 extends in a prescribed direction crossing the up-down direction X. In the examples shown in FIGS. 1 and 2, the prescribed direction coincides with the reference direction Y.

[0025] One of both ends of the coolant pipe 26 is the first end 261, and the other end is the second end 262. Both the first end 261 and the second end 262 are fixed to the side wall 161 of the first oil pan 16. For example, the coolant pipe 26 is integral with the first oil pan 16.

[0026] FIG. 3 is a schematic diagram illustrating a sectional shape of the oil pan 15 when the oil pan 15 is cut in an imaginary plane PH perpendicular to the cylinder arrangement direction. Oil flows into the oil pan 15 along at least one flow path. The coolant pipe 26 is set in a flow path 100. Therefore, the oil flowing along the flow path 100 comes into contact with the coolant pipe 26.

Functions and Effects of Embodiment

[0027] (1) In the internal combustion engine 10, the coolant channel 25 passes through the first oil pan 16 in the reference direction Y. The coolant pipe 26 constituting the coolant channel 25 extends in the reference direction Y, and the coolant pipe 26 is disposed in the first oil pan 16. Both the first end 261 and the second end 262 of the coolant pipe 26 are fixed to the side wall 161 of the first oil pan 16. This increases the rigidity of the first oil pan 16.

[0028] Specifically, an upper part of the first oil pan 16 is mounted to the cylinder block 11. The cylinder block 11 is a rigid component. Therefore, by mounting the upper part of the first oil pan 16 to the cylinder block 11, the rigidity of the upper portion of the first oil pan 16 can be secured.

[0029] On the other hand, a lower part of the first oil pan 16 is mounted to the second oil pan 17 having a lower rigidity than the cylinder block 11. Therefore, the rigidity of the lower part of the first oil pan 16 tends to be lower than the rigidity of the upper part of the first oil pan 16.

[0030] In this regard, in the internal combustion engine 10, the coolant pipe 26 is located closer to the second oil pan 17 than the middle in the up-down direction X of the first oil pan 16. Therefore, since the coolant pipe 26 is disposed at such a position, the rigidity of the lower portion of the first oil pan 16 is increased.

[0031] Therefore, the internal combustion engine 10 can increase the rigidity of the first oil pan 16.

[0032] (2) The coolant pipe 26 is installed in a flow path 100 of oil flowing into the oil pan 15. Thus, the coolant pipe 26 can reduce the temperature of the oil flowing into the oil pan 15.

Modifications

[0033] The above embodiment can be modified as follows. The above embodiment and the following modifications can be implemented in combination with each other as long as they are not technically contradictory. [0034] The coolant pipe 26 may be installed at such a position that it contacts the oil stored in the oil pan 15. In the embodiment illustrated in FIG. 4, the coolant pipe 26 is installed at a position in the downward direction X2 with respect to the oil level 200. Thus, the oil in the oil pan 15 can be cooled by the coolant flowing in the coolant pipe 26.

[0035] Further, as shown in FIG. 5, the coolant pipe 26 may be installed in a middle region in the cylinder arrangement direction Z of the first oil pan 16. For example, the middle region may be the middle portion in the case where the first oil pan 16 is equally divided into three in the cylinder arrangement direction. In the example illustrated in FIG. 5, the cylinder arrangement direction Z corresponds to a width direction perpendicular to both the 25 up-down direction X and the reference direction Y. This increases the rigidity of the first oil pan 16. [0036] The coolant pipe 26 may not be located in the flow path 100 as long as it is located closer to the second oil pan 17 than the middle in the up-down direction X of the first oil pan 16.

[0037] It should be noted that the expression at least one as used herein means one or more of the desired options. As an example, the expression at least one as used herein means only one option or both of two options if the number of options is two. As another example, the expression at least one as used herein means only one option or any combination of two or more options if the number of options is three or more.