JP2628268B2 - 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 having cylinders arranged in two directions (two rows) in a V-shape, that is, a V-shape.

[0002]

2. Description of the Related Art V-type diesel engines have external dimensions,
One of the features is that the dimensions of the crankshaft in the axial direction are short and compact. Diesel engines are equipped with a fuel injection pump, a gear train that transmits torque from the crankshaft to the intake / exhaust valve camshaft, fuel injection pump camshaft, etc., and a governor mechanism (governance control) for controlling the fuel injection amount and rotation speed. ), And further, a water pump for cooling each part with water and a drive mechanism thereof are integrally provided. Therefore, the above-described external dimensions naturally refer to the entire thing including these, and such dimensions are short. Is preferred.

An arrangement example of a governor mechanism and a water pump in a diesel engine is disclosed in Japanese Utility Model Laid-Open Publication No. 62-14164.
No. 0 and JP-A-59-175626, respectively. In the former, a governor mechanism is arranged on one side of a driving gear train such as a fuel injection pump camshaft so as to be housed in a gear case together with the gear trains. On the other hand, in the latter example, the water pump is formed on the same axis as the radiator fan, is attached to the outside of a gear case covering the same gear train as described above, and is driven together with the radiator fan by a fan belt. ing.

[0004]

Problems to be Solved by the Invention
According to the equipment arrangement described in Japanese Patent Publication No. 40, the equipment is densely arranged on one side of the gear train and the outer dimensions are expanded on that side,
There is a high possibility that the water pump and its drive mechanism cannot be arranged compactly. That is, while there is an empty space near the end of each shaft on the side opposite to the gear train,
On one side of the gear train, the components related to the fuel flow control of the governor mechanism are concentrated together with the gear train, and the gear case or governor case protrudes greatly to one side of the engine, thereby increasing the overall size of the engine. In addition, since it is difficult to provide the water pump on the side of the gear train where the above components are densely packed, the water pump must be provided in other parts together with a dedicated drive mechanism. It is.

On the other hand, in the case of Japanese Utility Model Unexamined Publication No. 59-175626, the space between the engine and the radiator is well utilized and the whole is compact as far as illustrated, but when the radiator is installed away from the engine, In addition, the water pump, the driving transmission belt and the pulley occupy a considerable space outside the engine, which is not preferable in terms of the compactness of the engine. Even with the same type of diesel engine, a fan and a radiator can be integrated into the engine depending on the application (generator or lawn mower, etc.), or a radiator can be connected to the engine together with an electric fan. In many cases, the above points are likely to cause inconvenience as restrictions on the use of the engine.

An object of the present invention is to reduce the overall size by arranging a governor, a water pump, a drive mechanism thereof and the like, including a fuel injection pump, in a reasonable and compact manner, and also to provide a separate radiator. It is to provide a V-type diesel engine without disadvantages.

[0007]

According to the V-type diesel engine of the present invention, a) a fuel injection pump chamber is provided between cylinders arranged in a V-type (that is, inside a V-shape);
b) A water pump is arranged on the side of the gear train including the driving gear of the fuel injection pump camshaft, and the water pump is
The fuel injection pump with gears attached to the impeller shaft
After meshing with the gears on the camshaft, cover the above gear train.
The gear case of the impeller shaft is
Retardant also covers, and on the opposite side to the side where the c) above gear train
The governor mechanism is arranged so as to be engaged with the shaft end of the fuel injection pump camshaft .

[0008] It is preferable that the V-type diesel engine is further configured as described in claim 2. That is, the gear train described above connects the crankshaft, the intake / exhaust valve camshaft, and the fuel injection pump camshaft in this order. The small gear meshes with the fuel injection pump camshaft.

[0009]

The V-type diesel engine of the present invention is compact as a whole in the following points.

First, since the fuel injection pump chamber is provided between the two rows of V-shaped cylinders as described in a), the fuel injection pump does not easily protrude outside the engine body. The overall dimensions can be reduced around the direction corresponding to the width. Although the pump is connected to the fuel injection nozzle on the cylinder head by a tube or the like, providing the pump chamber at such a position is preferable in that the connection distance between the pump and the nozzle is reduced.

Second, as shown in b) above, a water pump is arranged on the side where the transmission gear train is located , and
Fuel injection pump cam with gear attached to impeller shaft
Since the gear is meshed with the gear on the shaft, the driving means of the pump and its cover can be configured simply and compactly. In other words, for this pump, the drive means is completed simply by attaching one gear to the impeller shaft and meshing with the gear on the fuel injection pump camshaft, eliminating the need for belts, pulleys and other dedicated drive devices.
Was. As for the covers and to be covered such a driving means, can be made compact by that serves also as it originally gear case such that covers the gear train
Became. In addition, the driving means constructed in this way does not use a transmission belt for a radiator fan, so that no special space is required even when a radiator or the like is placed separately from the engine.

Third, in this V-type diesel engine, the governor is arranged on the side opposite to the side where the gear train is located as in the above c), so that the governor (and its covers) are provided.
Can protrude out of the engine. That is, the governor is provided at a position near the shaft end of the fuel injection pump camshaft or the like where the gear train is not arranged and there is room in space. In addition, this governor
-Mechanism is engaged with the shaft end of the fuel injection pump camshaft.
Therefore, it rotates and functions together with the camshaft.

[0013] In the case of the V-type diesel engine according to the second aspect, the distance between the crankshaft and the camshaft of the fuel injection pump (distance between the shaft centers) is further reduced, and the direction between the shafts, that is, at right angles to the crankshaft. The size of the engine in various directions can be reduced. The reason is as follows.

In a four-cycle diesel engine, intake and exhaust are repeated once for every two revolutions of the crankshaft.
Since the number of fuel injections is required, the number of rotations of the intake and exhaust valve camshaft and the number of rotations of the fuel injection pump camshaft must be reduced to 1/2 with respect to the number of rotations 1 of the crankshaft. To achieve this rotational speed ratio of each gear of the crankshaft, intake and exhaust valve cam shaft, the fuel injection pump cam shaft diameter (number of teeth), respectively _{d 1/2 (z 1/} 2), d 1 (z 1) , D ₁ (z ₁ ) 順 に, but it is also possible to engage in order.
In the type diesel engine, two gears having diameters (number of teeth) d ₁ (z ₁ ) and d ₂ (z ₂ ) are attached to the intake and exhaust valve cam shaft (where d ₁ > d ₂ ), and each of the above three shafts the diameter of the gear _{d 1/2 (z 1/} 2), d 1 (z 1) and d ₂ (z _2), after which the d ₂ (z ₂₎ ‥‥, two gears and rear wrote before (See FIG. 3).
The distance between the crankshaft and the intake valve cam shaft is no difference in _{(d 1/2 + d 1} ) / 2 = 3d 1/4 For the case of, between the intake valve cam shaft and the fuel injection pump cam shaft The required inter-axis distance is d _{2 in} the case of d ₁ in the case, and is smaller in the obvious case. This means that the distance from the crankshaft to the fuel injection pump camshaft is small and therefore the V
The fuel injection pump can be prevented from protruding upward from the letter to make the engine more compact.

The connection of the crankshaft, the intake / exhaust valve camshaft, and the fuel injection pump camshaft in this order as described above is achieved by disposing a valve mechanism (valve operating mechanism) for intake / exhaust inside the V-shape. In the sense that the portion that goes out is smaller than that, the overall size of the engine can be reduced. This is because the crankshaft is located at the intersection of the V-shaped cylinders and the fuel injection pump camshaft is also located between the V-shaped cylinders from the point a) in claim 1, so that the intake and exhaust are engaged with both. This is because, when the valve camshaft is arranged, the position of the intake / discharge valve camshaft is necessarily located inside the V-shape, so that the valve mechanism and the like are also arranged inside the V-shape, and the portion protruding outside the cylinder is reduced.

[0016]

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 schematic diagram of a built-in gear train. The angle between the cylinders of this engine is 90 ° as shown in FIG. 2, and the V-type has the advantage that the dimension in the axial direction (direction of the crankshaft 5) is short as shown in FIG. Note that in FIG.
Is a crankcase, 2 is a crankcase cover that also serves as a gear case, 5 is a crankshaft, 6 is a camshaft for intake and exhaust valves,
7 is a fuel injection pump cam shaft, 10 is a gear train between the respective shafts, 20 is a fuel injection pump, 30 is a governor mechanism, 40
Is a water pump. Reference numeral 25 is a flywheel, reference numerals 27, 28, and 29 are radiator fans and their driving belts and pulleys. In FIG. 2, reference numeral 17 is a piston, and reference numeral 22 is a fuel injection nozzle for each cylinder.

Although this engine has some structural features, the crankcase 1 has a new part. That is, as shown in FIG. 1, in addition to the original crankcase portion 1d, the cylinders 1a and 1b (FIG. 2), the fuel injection pump chamber 1c and the oil pan 1e are integrated,
The wall of the crankcase 1 near the fan 27,
It is formed by a separate crankcase cover 2. And, the crankshaft 5 inside the engine
The intake and exhaust valve camshafts 6 are formed so that bearing holes at both ends are divided into a crankcase 1 and a crankcase cover 2. The reason for this is to facilitate so-called die-cutting at the time of completion of casting and to rationalize the molding process. In particular, a mold (not shown) for the bearing hole and the inner reinforcing rib 9 can be easily formed. Can be extracted. In addition, such a crankcase 1 has an advantage that the crankshaft 5 and the intake / discharge valve camshaft 6 can be easily incorporated. Although the shaft 5 and the shaft 6 have a large-diameter portion such as a crank and a cam in a middle portion, the crankcase 1 and the crankcase cover 2 can be covered from outside the bearing portions on both sides. . In addition, about the joining of the crankcase 1 and the crankcase cover 2, in order to provide rigidity to resist the force by the explosion pressure in the cylinder,
A joint surface 1x extending from the bottom of the oil pan 1e to the upper portions of the cylinders 1a and 1b is formed, and the bolt 2a is formed as shown in FIG.
Has been concluded.

Further, in this engine, as shown in FIG. 2, the V-shaped center line formed by the cylinders 1a and 1b is
Three axes of a crankshaft 5, a suction / discharge valve camshaft 6, and a fuel injection pump camshaft 7 are arranged side by side. By arranging the three shafts in this manner, as shown in the figure, a valve operating mechanism 18 such as a push rod or a rocker arm engaged with the intake / discharge valve cam shaft 6 can be arranged inside each of the cylinders 1a and 1b. The width of the engine can be reduced.
Further, since the three shafts are arranged in a line, the shafts can be easily connected with a simple configuration without using an extra large gear or an intermediate idle gear.

Such a three-axis arrangement is also significant in making the engine compact as described above, but in terms of reducing the overall size, this engine also has significant features in the following devised parts.

First, in connection with the arrangement of the fuel injection pump camshaft 7 on the V-shaped center line, the fuel injection pump chamber 1c is also formed on that line, and the fuel injection pump 20 is placed there. It is attached. As shown in FIG.
Since the pump 20 is provided between the V-shaped cylinders 1a and 1b, and the pump 20 is not projected outward, the external dimensions of the engine, particularly, the dimension in the direction corresponding to the width of the V-shape are increased. I will not let you. Providing the pump 20 at this position has the advantage that the tube 21 connected to the fuel injection nozzle 22 is short and the path can be simplified.

The second point is that, as shown in FIG. 1, the water pump 4 is located on the side of the gear train 10 for transmitting the rotational force from the crankshaft 5 to the intake / discharge valve camshaft 6 and the fuel injection pump camshaft 7.
That is, 0 is arranged. When the pump 40 is provided near the gear train 10, it is only necessary to attach the driven gear 15 on the impeller shaft 41 and mesh with the gear 14 (part of the gear train 10) on the fuel injection pump camshaft 7. , Power transmission to it. When the pump 40 is attached to the inside of the crankcase cover 2 (also serving as a gear case) provided substantially parallel to the gear train 10 by bolts 42 as shown in the figure, a special case or cover for covering the gear 15 and the like is provided. Is unnecessary. Since the transmission belt 28 for the fan 27 is not used for driving the pump 40, the belt 28 and the like become unnecessary when the radiator (not shown) and the fan 27 are installed separately from the engine.
The pump 40 does not protrude outward.

The third point is that, as shown in FIG.
0 to the flywheel 25 opposite the side of the gear train 10
Is engaged with the shaft end of the fuel injection pump camshaft 7. On the flywheel 25 side, the gear 30 is not attached to the shaft end of the fuel injection pump camshaft 7 and the water pump 40 is not provided, so that the mechanism 30 can be arranged relatively freely. That is, the governor main body 31 attached to the camshaft 7, the governor arm 32 connecting the main body 31 to the fuel injection pump 20, and the like are brought close to the fuel injection pump chamber 1c, so that the governor cover 33 projects outside the engine. It could be made smaller.

A fourth point is that the gear train 10 includes two large and small gears which mesh with the gear 11 on the crankshaft 5 and the gear 14 on the fuel injection pump camshaft 7 as shown in FIG. That is, the gears 12 and 13 are fitted on the intake and exhaust valve cam shaft 6. That is, as shown in FIG.
A larger gear 12 having a diameter (pitch circle diameter) d ₁
Is engaged with the gear 11 of the crankshaft 5, and the smaller gear 13 having the smaller diameter d ₂ is replaced with the gear 14 of the fuel injection pump camshaft 7.
Is engaged with.

In a diesel engine, the rotational speed ratio of the crankshaft 5, the intake / exhaust valve camshaft 6, and the fuel injection pump camshaft 7 is 2: 1 based on the relationship between the rotational speed of the crankshaft 5, the frequency of intake and exhaust, and the timing of fuel injection. : 1, but taking this into account, each gear 11
The distance between each axis is as follows from the relationship of 12.13.14. That shown in Figure 3, is between the shaft 5 and the shaft 6 3d _1/4, between the shaft 6 and the shaft 7 becomes d _2, the center position of the shaft 7 will come to a point A shown. However if, if not with a gear 13 of smaller on the shaft 6, the above-mentioned rotational speed of the gear diameter d ₁ to axis 7 from the relationship is required, the crankshaft is the center position between point B Great distance from 5. Therefore, it can be said that the fourth contrivance also has an important significance in making the engine compact.

[0025]

According to the V-type diesel engine of the present invention, devices such as a fuel injection pump can be rationally and compactly arranged to reduce the overall size. Specifically, 1) Since the fuel injection pump is provided between the V-shaped cylinders, the outer shape can be reduced mainly in the direction corresponding to the width of the V-shape.

2) By arranging the water pump on the side where the gear train is located, the driving means of the pump and its cover can be simply and compactly constructed. Same
The drive means of the pump has a gear attached to its impeller shaft.
Just mesh with the gear on the fuel injection pump camshaft
The gears that cover the gear train
This is because the covering gear case also serves as such. In addition, since the driving means configured in this manner does not use a transmission belt for a radiator fan, it is advantageous when a radiator or the like is separately provided.

3) Since the governor is arranged on the side having a sufficient space, opposite to the side having the gear train, the degree of the governor or the like protruding out of the engine can be reduced.

4) In the case of the V-type diesel engine according to claim 2, the distance between the crankshaft and the fuel injection pump camshaft is further reduced, and the engine is moved in the interaxial direction, that is, in the direction perpendicular to the crankshaft. Can be reduced in size.

[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 schematically showing a gear train provided in the engine of FIG. 1;

[Explanation of symbols]

 1a ・ 1b Cylinder 1c Fuel Injection Pump Chamber 5 Crankshaft 6 Intake / Exhaust Valve Camshaft 7 Fuel Injection Pump Camshaft 10 Gear Train 11 ・ 12 ・ 13 ・ 14 ・ 15 ・ Gear 20 Fuel Injection Pump 30 Governor Mechanism 40 Water Pump

Claims (2)

(57) [Claims] Provided with a fuel injection pump chamber between 1. A cylinder arranged in V-type, a water pump is disposed on the side of the gear train including a drive gear of the fuel injection pump cam shaft, Lee of the water pump
Attach a gear to the impeller shaft and attach the fuel injection pump
Mesh with the gears on the gear shaft and cover the above gear train
The gear case allows the impeller shaft gears to be
Cover the fuel injection pump on the side opposite to the side with the gear train.
A V-type diesel engine, wherein a governor mechanism is arranged in engagement with a shaft end of a pucam shaft . 2. The gear train described above connects a crankshaft, a suction / discharge valve camshaft, and a fuel injection pump camshaft in this order, and attaches two large and small gears to the suction / discharge valve camshaft. The V-type diesel engine according to claim 1, wherein the small gear is meshed with the fuel injection pump camshaft while being meshed.