JP7584389B2 - Internal combustion engine - Google Patents

Description

The present invention relates to an internal combustion engine.

Conventionally, it is common for internal combustion engines to be equipped with oil jets that spray oil from below toward the cylinder bores of the cylinder block that houses the pistons in order to cool the pistons.

Patent document 1 discloses an engine in which an oil jet is attached by bolt fastening.

JP 2018-105254 A

However, with conventional technology, it was necessary to position the oil jet by first determining the center with the insertion part of the oil jet body, and then determining the direction of rotation with a bolt, making installation of the oil jet complicated.

The present invention was made in consideration of the above, and aims to eliminate the complication of installing an oil jet.

In order to achieve the above-mentioned object, the internal combustion engine of the present invention comprises a cylinder block, an oil jet that injects oil into the cylinder block, and a crankcase that houses a crankshaft, the crankcase having a recess for positioning the oil jet, the oil jet being fixed by sandwiching it between the cylinder block and the crankcase, the height and width directions of the recess having a shape that is at least approximately the same as the height and width of a main body of the oil jet, the recess being provided between a plurality of cylinder bores in the cylinder block, and the oil jet having a nozzle for each cylinder bore provided on each side of the recess.

According to the invention of claim 1, the oil jet is fixed by being sandwiched between the crankcase and the cylinder block, eliminating the need to bolt the oil jet itself and eliminating the hassle of installing the oil jet.

FIG. 1 is a vertical cross-sectional view showing the configuration of a main part of an engine for an automobile according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing the relationship between the cylinder bore and the oil jet as viewed from the bottom. FIG. 3 is a cross-sectional view taken along line AA of FIG.

The following describes in detail an embodiment of the internal combustion engine with reference to the attached drawings.

Here, FIG. 1 is a vertical cross-sectional view showing the configuration of the main parts of an automobile engine 100 according to the embodiment, FIG. 2 is a schematic diagram showing the relationship between the cylinder bore 5 and the oil jet 16 from a bottom view, and FIG. 3 is a cross-sectional view taken along the line A-A in FIG. 2.

As shown in FIG. 1, engine 100, which is an internal combustion engine for an automobile, includes a cylinder block 1 and a crankcase 2 provided at the bottom of the cylinder block 1.

The crankcase 2 houses the crankshaft 15. The crankcase 2 holds the crankshaft 15 rotatably via the crank cap 3 (see Figures 2 and 3).

As shown in FIG. 3, the bolts 18 that fasten the cylinder block 1 and the crankcase 2 are inserted into the cylinder block 1 from below the crankcase 2 via the crank cap 3. The cylinder block 1 is also formed with a boss portion that has a tapped hole into which the bolts 18 are screwed.

The cylinder block 1 forms a cylindrical cavity 4 inside. The cavity 4 of the cylinder block 1 has a cylindrical cylinder bore 5 disposed therein. The cylinder bore 5 has an inner cylindrical portion 5a. The inner cylindrical portion 5a of the cylinder bore 5 houses a piston 6 in a slidable manner.

The crankshaft 15 is disposed inside the cavity 4 in the crankcase 2. The crankshaft 15 is composed of a crank journal 15a, a crank pin 15b adjacent to the crank journal 15a, and a balance weight 15c disposed on the same plane as the crank pin 15b. The crank pin 15b and the piston pin 6a of the piston 6 are rotatably connected by connecting rods 14, so that the reciprocating motion of the piston 6 in the cylinder bore 5 is converted into the rotational motion of the crankshaft 15.

As shown in FIG. 2, the cylinder block 1 has four cylinders 7 aligned in the axial direction of the crankshaft 15. The cylinder block 1 and the crankcase 2 are cast aluminum products. However, the inner surface of each cylinder 7 (the inner cylindrical surface 5b of the cylinder bore 5) is made of an iron liner fixed by casting.

Furthermore, the engine 100 has an oil jet 16 disposed below the cylinder bores 5 and within the crankcase 2 for injecting oil into the inner cylindrical portion 5a of the cylinder bores 5 of the cylinder block 1. The oil jet 16 is connected to a main gallery 17 (see FIG. 3), which is an oil passage provided in the cylinder block 1 for flowing oil. As shown in FIG. 2, the oil jet 16 is provided between the cylinder bores 5 that constitute two adjacent cylinders 7.

The oil jet 16 has a main body 16b and a nozzle 16a that extends from the main body 16b toward the inside of the cylinder bore 5. The main body 16b has a built-in relief valve that allows oil to flow to the nozzle 16a when the oil pressure reaches a predetermined value. In this embodiment, the oil jet 16 has a bifurcated nozzle 16a. The oil jet 16 sprays oil into each cylinder bore 5 through the bifurcated nozzle 16a.

Next, we will explain the installation structure of the oil jet 16.

As shown in FIG. 3, the crankcase 2 has a recess 20 on the surface facing the cylinder block 1, the recess 20 having approximately the same shape as the body 16b of the oil jet 16. The recess 20 only needs to have a height that is at least approximately the same as the height of the body 16b of the oil jet 16. The recess 20 is provided so as to be located between the cylinder bores 5 of the cylinder block 1. The recess 20 is formed by performing countersinking and hole processing at a position on the crankcase 2 that faces between the cylinder bores 5 of the cylinder block 1.

The oil jet 16 has its main body 16b placed in the recess 20. The main body 16b of the oil jet 16 placed in the recess 20 is connected to the main gallery 17 and fixed between the cylinder block 1 and the crankcase 2. Here, since the recess 20 has approximately the same shape (height) as the main body 16b of the oil jet 16, the upper surface of the main body 16b of the oil jet 16 is flush with the opening surface of the recess 20, and the main body 16b of the oil jet 16 has contact surfaces with both the cylinder block 1 and the crankcase 2, so that it is fixed more firmly without the need for bolts or the like.

According to this embodiment, the recess 20 in which the body portion 16b of the oil jet 16 is placed is formed in the crankcase 2 by performing countersinking and hole machining, with a shape that is approximately the same as the shape of the body portion 16b of the oil jet 16. As a result, the body portion 16b of the oil jet 16 is fixed by sandwiching it between the cylinder block 1 and the crankcase 2, eliminating the complexity of installing the oil jet 16 and reducing the cost of parts. More specifically, only one hole is required to position the body portion 16b of the oil jet 16 in the crankcase 2, and screw machining to fix the body portion 16b of the oil jet 16 to the crankcase 2 is unnecessary.

In addition, by installing an oil jet 16 between the cylinder bores 5 of the cylinder block 1, the two oil jets that were previously required can be consolidated into an oil jet 16 with a bifurcated nozzle 16a, reducing the number of parts.

In addition, the side of the main body 16b of the oil jet 16 comes into contact with a recess 20 that has approximately the same shape as the main body 16b of the oil jet 16, forming a rotation stopper.

In addition, in the above explanation, the present invention has been described as being implemented in an internal combustion engine of an automobile, but the present invention may be implemented in any transportation device other than an automobile, such as a motorcycle, a train, a ship, or the like. Furthermore, the present invention may be applied to internal combustion engines such as diesel engines, as well as gasoline engines.

Therefore, the present invention may be implemented with various modifications to the above-described embodiment, including those described above, without departing from the spirit of the invention.

The present invention as described above has the effect of eliminating the hassle of installing oil jets, and is useful, for example, when applied to automobile engines.

Reference Signs List 1 Cylinder block 2 Crankcase 5 Cylinder bore 15 Crankshaft 16 Oil jet 16a Nozzle 20 Recess 100 Internal combustion engine

Claims (1)

A cylinder block;
an oil jet that injects oil into the cylinder block;
A crankcase that houses the crankshaft,
Equipped with
The crankcase has a recess for disposing the oil jet,
The oil jet is fixed by being sandwiched between the cylinder block and the crankcase,
The height and width directions of the recess have shapes that are at least approximately the same as the height and width of the main body of the oil jet,
The recess is provided between a plurality of cylinder bores in the cylinder block,
The oil jet has a nozzle for each cylinder bore provided on each side of the recess.
Internal combustion engine.

Images