JP2606780B2 - V-type diesel engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called V-type diesel engine in which cylinders are arranged in two directions (two rows) in a V-shape.

[0002]

2. Description of the Related Art The outer wall of a diesel engine is composed of various parts such as a cylinder, a crankcase, an oil pan, a fuel injection pump chamber, and a cylinder head. It is well known that the piston reciprocates inside the cylinder and the crankshaft rotates inside the crankcase.
Such an outer wall is usually formed by casting, but since it is impossible to integrally cast all of the outer wall, the outer wall is formed by dividing and joining somewhere.

In a conventional V-type diesel engine, a cylinder head is provided separately from a cylinder, and in many cases, a split / joint surface is provided between a crankcase and an oil pan. FIG. 4 shows an example in which a crankcase 51 integrated with cylinders 51a and 51b and a fuel injection pump chamber 51c is joined to a separate oil pan 52 at a lower joining surface 51x. A similar engine is disclosed in the drawings of Japanese Utility Model Publication No. 50-5016.

[0004] A similar division surface is formed in a portion other than the portion of the cylinder head and the oil pan (for example, at the center of the crankshaft bearing).
At present, there is no V-type diesel engine that is formed by splitting the crankcase itself in the axial direction of the crankshaft or the like (that is, forming a split surface that is substantially perpendicular to the shaft). . Therefore, a crankshaft, a camshaft for a suction / discharge valve, and the like are bridged over the conventional crankcase, and portions through which each shaft passes (bearing portions) are provided on both sides of the crankcase (wall surfaces near both ends of each shaft). ing. Such an example is disclosed in, for example, Japanese Utility Model Application Laid-Open No. 59-261.
No. 43 is shown in the drawings.

[0005]

When the crankcase is divided by an oil pan or the like as described above and is integrated in the axial direction of the crankshaft, it is not easy to form the crankcase by die casting or the like. This is because so-called die cutting after casting is not easy. If the crankcase 51 shown in FIG. 4 is taken as an example, the casting mold inside the crankcase 51 is pulled out in the direction in which the oil pan 52 is located (downward in the figure). In order to form the portion of the rib 59 for reinforcing the bearing boss and its periphery, and the corner portion X shown in the drawing, it is necessary to cut out the die in the direction of the axis (perpendicular to the plane of the drawing).
It is very difficult to produce by die casting.

Also, the crankshaft, the intake and exhaust valve camshaft, etc.
Since a portion having a larger outer diameter than the bearing portion, such as a crank and a cam, is provided between the two bearings, it is necessary to devise an assembly in order to arrange them in an integrated crankcase.
That is, at least one of the wall surfaces through which the shafts penetrate is formed with a large hole in advance, and after the shaft is inserted into the crankcase through the hole, a member including a bearing (or a bearing having a large outer diameter) is used. So as to close the hole (for example, such a description is given in the drawing of Japanese Utility Model Application Laid-Open No. 59-126143). This means
In addition to the above-mentioned inconvenience in molding of the crankcase itself, the number of parts is increased for reasons of assembly, and there is no other disadvantage in terms of manufacturing difficulty or cost.

SUMMARY OF THE INVENTION An object of the present invention is to provide a V-type diesel engine which has advantages in that the crankcase can be easily formed by die casting or the like, and the required amount of machining and the number of parts are not particularly increased. .

[0008]

SUMMARY OF THE INVENTIONClaim 1V type
Diesel engines are Cylinder and crankcase
The oil pan and fuel injection pump chamber are integrally molded
One of the wall surfaces of the crankcase
Shaft and a separate clutch including the intake and exhaust valve camshaft bearings.
Formed by joining the link case coverThat, V-shaped
Fuel injection, including the upper cylinders
Connected by pump room wall and clan
The joint between the crankcase and the crankcase cover,
From the bottom of the oil pan to the wall (that is, the fuel injection pump chamber)
Up to the top of the wall) and the top of the cylinder
− It is characterized by.

In this diesel engine, a crankcase and a crankcase are provided.
The above-mentioned ring-shaped connection to close the cover tightly
The joints should be spaced at the part that is integral with the side wall of each cylinder.
It is good to form it so that it may form two rows of inside and outside .

[0010]

According to the V-type diesel engine of the present invention, the crankcase is formed by being divided in the axial direction of the crankshaft.
The wall surface at one end in the axial direction is formed by a separate crankcase cover. That is, the crankcase has an opening perpendicular to (or substantially perpendicular to) the crankshaft and the intake / discharge valve camshaft parallel thereto, and has a joint surface with the crankcase cover around the opening. Such an opening is extremely useful in a so-called die-cutting stage in which a mold is disassembled after molding when the present crankcase is molded by die casting or the like. Through this opening, it is possible to remove the entire mold along the inside of the crankcase, and at the same time, remove the mold for molding the shaft hole and the rib around it in the same direction. Because it can be. Therefore, despite having the cylinder and the oil pan / fuel injection pump chamber integrally, this crankcase can be easily included including holes for each shaft by die-casting using a mold with a simple configuration with a small number of surfaces. It is molded. This effect is significantly different from the case where there is an opening parallel to the crankshaft or the like as shown in FIG. 4, for example. Since the crankcase cover forms the wall on one side of the crankcase and does not need to be a three-dimensional object including the other wall surfaces, it may be a flat plate as a whole. It is.

Further, since the crankcase and the crankcase cover can be divided and joined in the axial direction of the crankshaft, in this engine, the crankshaft or the intake / discharge valve camshaft having a large diameter portion such as a crank or a cam between both bearings is provided. Is easy to incorporate. In other words, if the crankcase and the crankcase cover are provided with holes sized as bearings for each shaft, the engine can be assembled by inserting them into both ends of each shaft, It is not necessary to provide such a large hole in the crankcase or to provide a member for closing it.

Since the cylinder, the oil pan, and the fuel injection pump chamber are integrated with the crankcase as described above, the engine is compact based on the structure shown in FIG. And does not change.

The diesel engine according to the present invention described in claim 1
With the engine, rigidity reinforcement required in connection with the fact that the wall surface on one side of the crankcase (the portion of the crankcase cover) is not integral with the crankcase body can be simply and effectively performed. V-shaped pair of syringes on both sides
Are connected by the wall of the fuel injection pump chamber, including its upper part.
High rigidity between the V-shaped pair of cylinders
This is because deformation is less likely to occur between the two. Ma
And, joining the crankcase and the crankcase cover 箇
From the position of the oil pan to the upper part of the wall of the fuel injection pump chamber
If it is provided up to the upper part of the cylinder and the cylinder , the crankcase cover is joined to that extent and the cover supplements the strength of the crankcase (in particular,
Where the wall of the storage room and the cover are joined,
It becomes a heavy reinforcing member) . That is, since a diesel engine has a higher explosion pressure than a gasoline engine, a large tensile force acts between the cylinder and the crankcase, and displacement is likely to occur around a boundary between the two (the base of the cylinder). To form the wall
If the crankcase cover is attached by providing a joint portion up to the upper part, displacement due to explosion pressure or the like, which is likely to occur at the boundary or the like, is suppressed. In addition, if the bonding surface is provided up to the upper part, the opening inside is widened, and there is an advantage that the above-described die-cutting is further facilitated.

According to the first aspect of the present invention, one of the crankcases is provided.
Side (the side with the joint surface with the crankcase cover)
The cylinder side wall and fuel injection from the oil pan
The above joints are connected in a ring over the wall of the pump chamber, etc.
The V-type diesel engine of claim 2
In the engine, the side wall of each cylinder
The upper part should be two rows of inner and outer rows spaced
Formed. Thus double joining on the side wall of the cylinder
Place and join the crankcase cover through this
If you do, the crankcase and the crankcase cover
Not only the joint becomes strong, but also the rigidity of the cylinder itself
Suitable for diesel engines with high explosion pressure
Reinforcement is made.

[0015]

1 to 3 show an embodiment of the present invention. This example relates to a two-cylinder V-type diesel engine, and FIG. 1 is a longitudinal sectional view (FIG.
FIG. 2 is a partially cutaway front view, and FIG.
FIG. 3 is a view taken in the direction of arrows III-III in FIG. 1. Figure 2 shows the included angle between cylinders.
As shown in FIG. 1, there is an advantage that the dimension in the axial direction (direction of the crankshaft 5) is short because of the V-shape. In FIG. 1 (and FIG. 2), reference numeral 21 denotes a fuel injection pump, 22 (FIG. 2) denotes a fuel injection nozzle for each cylinder, 23 denotes a governor, 24 denotes a water pump, 25 denotes a flywheel, and 27 and 26 denote fans. The driving pulley. Reference numerals 3 and 4 (FIG. 2) denote cylinder heads.

The structural features of this engine are as follows. As shown in FIG. 1, the crankcase 1 includes cylinders 1a and 1b (FIG. 2), a fuel injection pump chamber 1c, and an oil pan in addition to the original crankcase portion 1d. 1e and the fan 27 of the crankcase 1.
The point is that the closer wall surface is formed by a separate crankcase cover 2. Inside the engine, the crankshaft 5, the intake / discharge valve camshaft 6, the fuel injection pump camshaft 7, etc. are rotatably provided together with the piston 17 (FIG. 2). In relation to the above, the bearing holes at both ends were formed separately in the crankcase 1 and the crankcase cover 2. That is, as shown in FIG. 1, first, one bearing 1g for supporting the crankshaft 5 is provided on the crankcase 1, and the other bearing 2g is provided on the crankcase cover 2 (reference numerals 1h and 2h are oil seal materials). Similarly, bearing portions 1i and 2i of the intake and exhaust valve camshaft 6 are formed on the crankcase 1 and the crankcase cover 2, respectively. However, regarding the fuel injection pump camshaft 7,
Since the bearings 1j and 1k can support the wall surface of the fuel injection pump chamber 21 and it is not necessary to extend the shaft length to the position of the crankcase cover 2, all the bearing holes are provided only in the crankcase 1.

The crankcase 1 and the crankcase cover 2 are formed by die casting of an aluminum alloy.
Based on the above configuration, this engine has an advantage that the molding of the crankcase 1 is easy. When casting is completed, a mold (not shown) for the bearing holes of the crankshaft 5, the suction / discharge valve camshaft 6, and the fuel injection pump camshaft 7
Together with a mold (same as above) for forming an internal space as a crank chamber and a mold (same as above) for a rib 9 for reinforcement.
This is because it can be extracted from the opening inside the joining surface 1x. In addition, a mold for the fuel injection pump chamber 21 is separately prepared, and the mold is cut in a direction different from the opening of the joint surface 1x.
Since the crankcase cover 2 is generally flat and can be die-cut in one direction (left and right in FIG. 1), it is needless to say that the molding is easy.

In addition to the above configuration, there is an advantage that the crankshaft 5 and the intake / discharge valve camshaft 6 can be easily incorporated. Regarding the crankshaft 5, the main body of the shaft 5 before the flywheel 25 and the pulley 26 are attached is shown in FIG.
Since the crankcase 1 and the crankcase cover 2 can be covered from both ends up to the position shown in FIG. 1, it is not necessary to devise a device for assembling (such as providing a special large shaft hole) exclusively. The same applies to the intake / exhaust valve cam shaft 6. In this example of the engine, the bearing hole of the shaft 6 of both the crankcase 1 and the crankcase cover 2 could be a non-penetrating type. Therefore, conventionally, the crankcase 1
There is no need for a sealing means or a protection member which is necessary for a portion where the shaft 6 protrudes from the crankcase cover 2.

The connection between the crankcase 1 and the crankcase cover 2 was made by bolts 2a as shown in FIG. 1, but the connection between the two was made on the crankcase 1 by an oil pan 1e as shown in FIG. A joint surface 1x extending from the bottom to the upper portion of the fuel injection pump chamber 1c and the upper portions of the cylinders 1a and 1b is formed, and a corresponding joint surface (not shown) on the crankcase cover 2 is overlapped therewith. . This joint (joint surface 1x) is
To close the crankcase cover tightly,
It is a series of cages, but on the side of each cylinder 1a and 1b
In the part that is integral with the wall, the joint is located inside and outside as shown.
It is formed in two rows. When the engine is running, the cylinder 1a
Opening the wall of the crankcase 1 at one end of the crankshaft 5 has many disadvantages due to the rigidity of the engine, because a force is generated to separate the crankcase 5 from the crankshaft 1b. The required rigidity is supplemented by joining the crankcase cover 2 to the crankcase 1 at the simple joining surface 1x. The wall including the crankcase cover 2 and the joint surface 1x therewith (FIGS. 2 and 3)
Fuel injection pump connecting between cylinders 1a and 1b
The wall of the chamber 1c) is the cylinder 1 where displacement is most likely to occur.
This is because the crankcase 1 is reinforced over a wide area including the bases of a and 1b. In addition, FIG.
The above two sections reinforce each cylinder 1a, 1b, etc.
Because it does. The fact that the crankcase cover 2 is flat as a whole and has a shape in which bending displacement does not occur due to an in-plane force also has an advantageous effect on rigidity.

Further, in this engine, as shown in FIGS. 2 and 3, the crankshaft 5 and the intake / discharge valve camshaft 6 are placed inside the V-shape formed by the cylinders 1a and 1b (that is, within a 90 ° included angle). The three axes of the fuel injection pump camshaft 7 are arranged side by side. The crankshaft 5 is arranged at the center of the V-shape where the extension lines of the cylinders 1a and 1b intersect, and the other two axes, that is, the positions of the shafts 6 and 7, are positioned directly above the crankshaft 5, that is, the included angles of the cylinders 1a and 1b. On a vertical line that is exactly one half of

Such a three-axis arrangement has the following advantages that lead to downsizing and simplification of the engine. That is, first, since the intake and exhaust valve camshaft 6 is inside the V-shape, the valve operating mechanism 18 such as a push rod or a rocker arm connected to the valve 19 as shown in FIG.
Can be arranged inside each of the cylinders 1a and 1b, and the width of the engine viewed in the direction of FIG. 2 can be reduced. As a second advantage, since the three axes are arranged in a line, the gear train between them can be simplified. That is, as shown in FIG. 1, the gear 11 provided on the shaft 5 and the gears 12 and 13 on the shaft 6 and the gear 14 on the shaft 7 just inside the crankcase cover 2 (these And the gears necessary to drive the shaft 7) are extremely simple and compact, with no additional intermediate gears and without the use of extra large gears or other transmission means such as chains and belts. It was decided to combine. The gear 14 for the shaft 7 and the driving gear 28 of the water pump 24 meshed with the shaft 14 are arranged in a space formed between the crankcase cover 2 and the fuel injection pump chamber 1c due to the planar shape of the crankcase cover 2. Another advantage is that the engine can be made compact by eliminating dead space inside.

[0022]

The V-type diesel engine of the present invention has the following effects.

1) Since one side wall of the crankcase is formed by a separate crankcase cover, the crankcase can be easily formed at a low cost by die casting using a mold having a simple structure with a small number of surfaces. It is effective in improving engine productivity and cost. A hole through which the crankshaft and the intake / exhaust valve camshaft pass can also be provided in the crankcase in that step, so that there is no disadvantage in increasing the number of subsequent machining steps.

2) The crankshaft and the intake / discharge valve camshaft can be easily assembled, and the configuration and parts required only for the installation are unnecessary, which is more advantageous in terms of productivity and cost.

3) Explosion pressure higher than gasoline engine
There rigidity required as the outer wall of the diesel engine, Siri
It is effectively supplemented by simple means such as a wall connecting the cylinders and a crankcase cover . The means of reinforcement is simple
As a result, it has the effect of avoiding an increase in engine weight.
There is fruit .

4) The diesel engine according to claim 2
More appropriately, such as increasing the rigidity of the cylinder.
Done.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing a V-type diesel engine as one embodiment of the present invention as viewed from a side (a sectional view taken along line II of FIG. 2).
It is.

FIG. 2 is a partially cutaway front view of the engine of FIG. 1;

FIG. 3 is a front view showing a joint surface of a crankcase and the like of the engine in FIG.

FIG. 4 is a front view showing a cross section of a conventional V-type diesel engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crankcase 1a ・ 1b Cylinder 1c Fuel injection pump room 1d Crankcase part 1e Oil pan 1x Joint surface 2 Crankcase cover 5 Crankshaft 6 Intake / exhaust valve camshaft 7 Fuel injection pump camshaft 11 ・ 12 ・ 13 ・ 14 Gear

Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location F02F 1/00 F02F 1/00 P (56) References JP-A-61-265341 (JP, A) 50-5016 (JP, U)

Claims (2)

(57) [Claims] 1. A crankcase having a cylinder, an oil pan, and a fuel injection pump chamber integrally, and a separate crankcase cover having bearings for a crankshaft and a suction / discharge valve camshaft is joined to the crankcase. be Te, both sides of the cylinder a pair of V-shaped, including the upper portion thereof retardant
That are connected by a wall of the fuel injection pump chamber, and a crank case and the crank case cover
From the bottom of the oil pan to the top of the wall
V-type diesel engine that extends to the upper part of the cylinder . 2. A crankcase and a crankcase cover.
The above joints that are connected in an annular shape to tightly close
However, at the part that is integral with the side wall of each cylinder,
2. An inner and outer two-row row is formed.
A V-type diesel engine according to Claim 1.