JPH0432495Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an integrated bearing cap structure for an internal combustion engine that integrates a plurality of bearing caps that pivotally support a crankshaft.

(Prior Art and its Problems) Various types of integral bearing caps in which a plurality of bearing caps are fastened in the longitudinal direction of an engine have been known. This conventional integrated bearing cap (integral bearing cap)
Although this can be easily applied to a shot skirt type cylinder block, it is difficult to apply an integral bearing cap to a cylinder block with a skirt in which the lower part of the cylinder block is extended for the following reasons.

Large openings are required at both ends of the cylinder block, reducing the strength of the block, requiring reinforcement, and increasing noise.

The oil seal that covers the longitudinal end of the cylinder block becomes larger, making it impossible to use a plate-shaped oil seal. Furthermore, since the end of the integrated bearing cap is covered with an oil pan, the overall length of the engine becomes longer, making it difficult to make it more compact.

(Purpose of the invention) In view of the above circumstances, the present invention provides an integrated bearing cap structure for an internal combustion engine suitable for a cylinder block with a skirt, which can suppress noise and vibration of an internal combustion engine having a cylinder block with a skirt. The purpose is to

(Structure of the invention) (1) Technical means This invention connects a plurality of bearing caps, which support the crankshaft of an internal combustion engine to a cylinder block with a skirt, with a plurality of beams extending in the longitudinal direction of the engine's crankshaft. In the integrated bearing cap, beams are arranged at multiple locations so that the beams surround the rotation locus of the crankshaft, and at least one beam each is provided on both sides in the engine width direction across the crankshaft center line. The beams are gathered together to form a frame shape at either or both ends of the crankshaft in the longitudinal direction, and a small protrusion integrally protrudes from the gathering part in the longitudinal direction of the crankshaft. This is an integrated bearing cap structure for an internal combustion engine, characterized in that it is formed continuously on the lower surface of a narrow bearing cap that protrudes from the crankshaft in the longitudinal direction.

(2) Effect Since the small protrusion is surrounded by the skirt of the cylinder block, the opening of the cylinder block becomes smaller, improving the strength of the cylinder block and reducing noise.

(Example) Fig. 1 shows a three-cylinder diesel engine employing the present invention, in which numeral 10 is a cylinder block;
1 is a crankshaft, 12 is a piston, and 13 is a connecting rod. A flywheel 14 is fixed to the right end of the crankshaft 11 in FIG. 1, and a pulley 15 is fixed to the left end. At the bottom of the cylinder block 10 is a retainer frame 16 (second
The oil pan 17 is fixed via the (Fig.).

At the bottom of the cylinder block 10, as shown in FIG. 2, a skirt portion 18 extends downward by a height H from the center line O of the crankshaft 11. 19 is a camshaft.

In FIG. 1, a journal portion 20 of the crankshaft 11
The cylinder block 10 is integrally supported by an upper half bearing 21 and a lower half bearing cap 22, and the four bearing caps 22 are connected in the longitudinal direction of the crankshaft 11 by a beam 23 (Fig. 2). has been done. These bearing caps 2
2. The beam 23 and the like constitute an integral bearing cap 24, which will be described in detail later.

In FIG. 3, which is a plan view of this integral bearing cap 24, two beams 23 are connected to the crankshaft 1.
They are arranged in symmetrical positions vertically (in the engine width direction) in the figure across the center line O1 of the engine 1, and extend parallel to the center line O1 left and right (in the longitudinal direction of the crankshaft). The two intermediate bearing caps 22 are integrally connected to the beam 23 by a connecting portion 25 (FIG. 5) extending in a substantially V-shape.

Both ends of the beam 23 are integrally connected to a collection part 26 extending vertically in FIG. 3, and the beam 23 and the collection part 26 are formed into a substantially frame shape. A protrusion 30 that protrudes left and right (in the longitudinal direction of the crankshaft) in FIG. 6 is integrally formed in the center of the bottom surface of the left and right gathering parts 26, and this protrusion 30 converges with the lower surfaces of the bearing caps 22 at both ends. The portions 26 are connected. A screw hole 31 is formed in the protrusion 30 at the right end (flywheel side end) in FIG.
An oil seal 33 and a protrusion 30 are fastened together with a bolt 32 (FIG. 1) in a screw hole 31.

In FIG. 1a, which is a partial cross-sectional view taken along line a-a in FIG. 1,
The right end portion 34 of the retainer frame 16 has a gap 35.
The bearing cap 22 is surrounded from below by being separated from the bearing cap 22. The bearing cap 22 is fixed to the bearing portion 21 (FIG. 1) of the cylinder block 10 with bolts 36. Two bolts 36 are provided for each bearing cap 22, and eight bolts 36 are provided for the entire integral bearing cap 24.

The gap 35 is filled with an aluminum plate-shaped oil seal 3.
3, as shown in FIG.

In FIG. 7, which is a cross-sectional view of FIG. 3, the two beams 23 are arranged so as to surround the trajectory T1 of the crankshaft 11 so as not to interfere with the trajectory T1. At the portion of the integral bearing cap 24 where the connecting portion 25 is provided, the skirt portion 18 of the cylinder block 10 is open as shown by the trajectory T2, but at both ends of the integral bearing cap 24, the skirt portion 18 is open. is the trajectory T3 (6th
A relatively small opening as shown in Figure) is sufficient.

In the above integral bearing cap 24, 4
bearing caps 22 and two beams 23
Since they are connected in the longitudinal direction of the crankshaft 11, vibrations of the crankshaft 11 are reduced.

At both ends of the skirt portion 18 in the longitudinal direction of the engine, small openings indicated by the locus T3 surround the protrusion 30 of the integral bearing cap 24, thereby increasing the strength of the cylinder block 10 and reducing noise. Therefore, even when an integrated bearing cap is adopted for the cylinder block 10 having the skirt portion 18, the opening of the skirt portion 18 is smaller than before, which is suitable for the cylinder block 10 having the skirt portion 18.

At the right end of the oil pan 17 in FIG.
The flange 40 of the oil pan 17 is secured to the right end 34 of the retainer frame 16 adjacent the lower end of the projection 30 of the integral bearing cap 24. Therefore, as shown in FIG. 12 which shows the conventional case, the right end 34' of the retainer frame 16 is extended rightward by L to form the integrated oil seal 3.
3' from below, the right end of the integrated bearing cap 24 is connected to the oil pan 17 by the right end 34' of the oil pan 17 and the retainer frame 16.
Also, compared to the case where the engine is housed inside the retainer frame 16, the length of the engine is shorter by the length L (FIG. 1).

Since the oil seal 33 in FIG. 1 is shaped like an aluminum plate, it is lightweight and is suitable for closing the gap 35. This oil seal 33 is a cast oil seal 33' shown in FIG. 12 that is integrated with a so-called bell housing that covers the flywheel 14.
Manufacturing costs are low compared to.

As described above, the integrated bearing cap 24 of the present invention is not limited to the case where the beam 23 is extended substantially straight, but also has a beam 50 which is vertically curved in a waveform as shown in FIGS. 10 and 11 to form an integral bearing cap 24, or as shown in FIGS.
It is also possible to form the integrated bearing cap 24 with a beam 52 extending in the engine width direction along the inner surface of the shaft 8, and to fix the beam 50 and the skirt portion 18 with bolts 53.

Furthermore, the bolt 32 in FIG.
This is provided to connect the integral bearing cap 24 with the protrusion 30 to more firmly fix the integral bearing cap 24.
It is fixed to the cylinder block 10 by the bolt 36 (FIG. 1a). Therefore, the bolt 32 is not an essential component, and the present structure can be established even without the bolt 32.

(Effect of the invention) As explained above, in the integrated bearing cap structure of the internal combustion engine according to the invention,
As shown in the figure, the beams 23 are arranged at multiple locations so that the beams 23 surround the rotation locus T1 of the crankshaft 11, and at least one beam 23 is placed on both sides of the engine width direction across the crankshaft center line O1. The beams 23 are assembled into one frame shape at either or both ends of the crankshaft longitudinal direction, and a small protrusion protrudes in the crankshaft longitudinal direction at the aggregated part 26 of the beam. 30, the four bearing caps 22 are
The crankshaft 11 can be connected in the longitudinal direction with the main beam 23, and vibrations of the crankshaft 11 can be reduced.

At both ends of the skirt portion 18 in the longitudinal direction of the engine, small openings shown by the locus T3 surround the protruding portion 30 of the integral bearing cap 24, thereby increasing the strength of the cylinder block 10 and reducing noise leaking from the skirt portion 18 to the outside. Can be reduced.

Therefore, even if the integrated bearing cap 24 is adopted for the cylinder block 10 which has the skirt portion 18 extending downward by the height H from the crankshaft center line O, the small opening (trajectory T3) of the skirt portion 18 will cause The body bearing cap 24 can be fixed.

The protruding portion 30 is integrally connected to the gathering portion 26 and continues to the lower surface of the bearing cap 22 at both ends.
Locus T3 seen from the bottom of the opening of the skirt portion 18
also becomes smaller as shown in Figure 6.

[Brief explanation of the drawing]

Fig. 1 is a vertical front partial view of a diesel engine adopting the present invention, Fig. 1a is a partial cross-sectional view taken along the a-a line in Fig. 1, Fig. 2 is a vertical cross-sectional partial view, and Fig. 3 shows an integrated bearing cap. 4 is a cross-sectional view of FIG. 3, FIG. 5 is a view taken in the direction of the arrow in FIG. 4, FIG. 6 is a view taken in the direction of the arrow in FIG. 4, and FIG. 8, 9, 10, and 11 are structural diagrams showing other embodiments, and FIG. 12 is a structural diagram showing a conventional example. DESCRIPTION OF SYMBOLS 10... Cylinder block, 11... Crankshaft, 18... Skirt portion, 22... Bearing cap, 23... Beam, 24... Integral bearing cap, 26... Collective portion, 30... Projecting portion.

Claims (1)

[Scope of utility model registration request] In an integrated bearing cap, a plurality of bearing caps, which pivotally support the crankshaft of an internal combustion engine on a cylinder block with a skirt, are connected by a plurality of beams extending in the longitudinal direction of the engine's crankshaft.The beams follow the rotation trajectory of the crankshaft. Arrange the beams in multiple parts so as to surround them, and at least one beam in each part.
The main beams are provided on both sides in the engine width direction across the crankshaft center line, and are gathered into a single beam at either or both ends of the crankshaft longitudinal direction to form a frame shape. An integrated bearing for an internal combustion engine, characterized in that a small protrusion integrally protruding from the collective part of the beam in the longitudinal direction of the crankshaft is formed on the lower surface of a narrow bearing cap that protrudes from the collective part in the longitudinal direction of the crankshaft. Cap structure.