JPS6346694Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a device that enables highly accurate setting of fuel injection timing when assembling a fuel injection pump mounted on an internal combustion engine.

<Prior Art> In an engine equipped with a fuel injection pump, such as a diesel engine, it is necessary to set the fuel injection timing corresponding to the rotational position of the crankshaft and assemble the pump.

The setting of such fuel injection timing has conventionally been performed as follows. That is, as shown in FIG. 1, a crank gear 4, a cam gear 5, an idle gear 7, and a pump gear D, which interlock the crank shaft 3 of the internal combustion engine 1 and the pump drive shaft B of the fuel injection pump A, are in mesh with each other. , match marks 4a, 5a, respectively.
7a and _D1 , and a mark 2a' is placed on the upper end surface of the end plate 2 fixed to the front end wall of the cylinder block, corresponding to the pump mounting position.

Then, after fitting and fitting the respective gears with matching marks, the fuel injection pump A
is attached by aligning the positioning mark C previously made on its main body with the mark 2a' of the end plate 2, and aligning the match mark _D1 of the pump gear D with the match mark 7a of the idle gear 7 to be engaged. By doing this, the relative rotational position between the piston position (crank angle) and the injection position (internal cam angle) of fuel injection pump A is determined, and the fuel injection timing (usually at the beginning of injection in the #1 cylinder) is determined. (indicated by the difference between the piston top dead center position and the piston top dead center position). Note that E is a timer integrated with pump gear D, and F is a bolt.

<Problem to be solved by the invention> However, in this conventional system, the rotational positions of the pump body and the pump drive shaft are determined separately, and therefore the drive power transmission system from the crankshaft to the pump drive shaft is configured. The processing accuracy of each member directly affects the accuracy of fuel injection timing.

For this reason, strict processing accuracy is required for the components of the driving force transmission system, leading to a decrease in production efficiency and an increase in costs.

It is also possible to assemble the pump while adjusting the fuel injection timing by rotating the crankshaft 3 for each product, but this would require extremely troublesome work and would significantly reduce production efficiency, so it would not be cost-effective to do so. Therefore, its adoption was impossible.

The present invention was developed in view of these conventional drawbacks, and allows the fuel injection timing to be set with high precision without variation from product to product with a relatively simple operation, and also allows the crankshaft and pump drive shaft to be linked. The present invention provides a fuel injection timing setting device for a fuel injection pump that can reduce the machining accuracy of drive force transmission system components, improve production efficiency, and reduce costs.

<Means for Solving the Problems> Therefore, the present invention transmits the rotational driving force of the crankshaft 3 to the pump drive shaft B of the fuel injection pump A via a plurality of gears 4, 5, 7, D, and The rotational position of each gear 4, 5, 7, D is
Matching marks 4a, 5a, 7 made on 5, 7, D
a, D ₁ at a predetermined rotational position of the crankshaft 3, and positioning the fuel injection pump A with respect to the fuel injection pump mounting hole 8 formed in the end plate 2 on the side of the engine body. In an internal combustion engine, a dummy gear 22 is formed to have the same tooth shape as the pump gear D fixed to the end of the pump drive shaft B, and is provided with a matching mark 7a; An outer cylindrical member 21 that fixes a dummy gear 22 and is integrally provided with a plate portion 21a having a matching mark 21b; an inner cylindrical member 20 that rotatably supports the dummy gear 22 and the outer cylindrical member 21; and a crankshaft. At the predetermined rotational position of No. 3, the gears 4, 5, and 7 are positioned and meshed, and after the fuel injection pump A is installed, the gear 7 that is meshed with the pump gear D and the dummy gear 22 are aligned with matching marks 7a, With 22a aligned and engaged,
The inner cylinder member 20 is positioned with respect to the fuel injection pump mounting hole 8 and fastening members 11 and 13 are fastened to the end plate 2 in a detachable manner.

<Function> The crankshaft 3 of the fuel injection pump A before installation is set at a predetermined rotational position, and each of the gears 4, 5,
7 are positioned and engaged, and the gear 7 and the dummy gear 22, which are engaged with the pump gear D after the fuel injection pump A is installed, are aligned and engaged with the matching marks 7a and 22a made on each of the gears 7 and 22, respectively. The inner cylinder member 20 is connected to the fastening member 1
1 and 13, it is positioned with respect to the fuel injection pump mounting hole 8 and fastened to the end plate 2.

At this position, a mark 2 is placed on the end plate 2 in alignment with the mark 21b made on the plate portion 21a.
After performing step a, the dummy gear 22 and the outer cylinder member 2
1 and the inner cylinder member 20 from the fuel injection pump mounting hole 8, and remove the matching mark made on the pump gear D.
Attach D ₁ in alignment with the matching mark 7a of the gear 7, and attach the fuel injection pump A by aligning the mark C previously made on the fuel injection pump A with the mark 2a made on the end plate 2. Accordingly, the fuel injection timing of the fuel injection pump A is set.

<Examples> The present invention will be described in detail below based on illustrated examples. The components common to Figure 1 are:
The explanation will be given using the reference numerals shown in FIG.

In FIG. 2, an end plate 2 is fastened to the front end wall of the cylinder block of the engine 1 before the fuel injection pump A is assembled. A crank gear 4 is fixed to the front end of the crankshaft 3 protruding from the end plate 2 on the side of the engine body, and a cam gear 5 meshing with the crank gear 4 and the cam gear 5 is integrally attached to the camshaft 6. A pump drive shaft B connected to the pump gear D through a plurality of gears, including a fixed idle gear 7 and a pump gear D meshing with the idle gear 7, rotates in conjunction with the crankshaft 3. .

The crank gear 4 and the cam gear 5 are provided with matching X marks 4a and 5a for positioning the relative rotational position of the crankshaft 3 and the camshaft 6 and setting the opening/closing timing of the intake and exhaust valves. Matching marks 7a and _D1 indicated by Y marks are provided around the set engagement position of No. 5, and also on the idle gear 7 and pump gear D to determine their relative positional relationship, and the fuel injection pump A end plate 2
As in the conventional case, a mark C for positioning the fuel injection pump mounting hole 8 formed in the fuel injection pump mounting hole 8 is provided.

Next, the configuration of the fuel injection timing setting device according to the present invention will be explained with reference to FIGS. 2 and 3.

This device is composed of a first assembly 11, a second assembly 12, and a handle member 13.

That is, the first assembly 11 joined to the back side of the end plate 2 has a circular protrusion 14 and a bolt inserted into the fuel injection pump mounting hole 8 formed in the end plate 2 and the pump mounting bolt 9, respectively. A disk 16 with an insertion hole 15 formed therein, and a shaft 18 that penetrates through the center of the disk 16 and is fixedly attached to the disk 16 and has a thread 17 formed in its front end.
It is composed of: Further, a hole 19 is formed in the disk 16 to fit a pin 26 of the second assembly 12, which will be described later.

On the other hand, the second assembly 12 joined from the front end side of the end plate 2 has a shaft 18 that projects forward from the fuel injection pump mounting hole 8 of the first assembly 11.
an inner cylindrical member 20 that can be freely inserted into the inner cylindrical member 2;
0, and a cylindrical dummy gear 22 fastened to the front surface of the outer cylinder member 21.

The outer cylindrical member 21 is prevented from coming off in the axial direction by a retaining ring 24 fitted onto the outer peripheral surface of the front end of the inner cylindrical member 20 and a flange 25 formed at the rear end. A portion of the disk 16 is formed to protrude in the radial direction so as to sandwich the peripheral edge of the fuel injection pump mounting hole 8 of the end plate 2 between the disk 16 and the flange portion 25 .

Further, a positioning plate portion 21a extending radially outward is formed at the rear end of the outer cylinder member 21,
The outer end surface of the plate portion 21a is formed so as to be at the same height as the upper end surface of the end plate 2 when brought to the upper position.

A mark 21b is provided on the outer end surface of the plate portion 21a in the axial direction of the shaft 18 as shown.

Further, the dummy gear 22 has the same tooth shape as the pump gear (same number of teeth, same meshing radius), and is provided with a matching mark 22a indicated by a Y mark at a predetermined peripheral position.

Here, a mark 21b made on the plate portion 21a and a matching mark 2 made on the dummy gear 22 are shown.
2a means that when the mark C on the front end wall of the fuel injection pump A is aligned with the mark 21b and the matching mark _D1 on the pump gear D is aligned with the matching mark 22a, when the pump is assembled. The fuel injection timing is set at a relative rotational position such that the fuel injection timing corresponds to the three rotational positions of the crankshaft.

The handle member 13 is connected to the shaft 18 of the first assembly 11.
A boss is formed with a female thread 27 that engages with the male thread 17 formed at the tip, and that presses the front end surface of the inner cylinder member 20 and fastens both assemblies 11 and 12 by the threading of both the threads 17 and 27. portion 28 and a pair of handles 2 extending in a radial direction from the outer peripheral surface of the boss portion 28.
9.

A fuel injection timing setting method using the fuel injection timing setting device having the above configuration will be explained.
In FIG. 2, the cam gear 5, which is integrally connected to the camshaft 6 with the idle gear 7, and the crank gear 4, which is connected to the crankshaft 3, are marked by matching marks 5.
a, 4a are aligned and engaged, insert the inner cylinder member 20 into the shaft 18 of the first assembly 11 that protrudes from the fuel injection pump mounting hole 8, fit the pin 26 into the hole 19, and then Join the assemblies 11 and 12.

Then, the female thread 27 of the handle member 13 is connected to the male thread 17 at the tip of the shaft 18 protruding from the inner cylinder member 20.
screw in and fasten both assemblies 11 and 12.

Here, the first assembly 11 is positioned and joined to the fuel injection pump mounting hole 8 by the circular protrusion 14, and the first assembly 11 and the inner cylinder member 2
0 is positioned by inserting the shaft 18 and fitting the hole 19 and the pin 26. Therefore,
The first assembly 11 and the handle member 13 constitute a fastening member that is positioned with respect to the inner cylinder member 20 and the fuel injection pump mounting hole 8 and fastened to the end plate 2.

However, the configuration of the fastening member is the same as the first one as long as the inner cylinder member 20 is positioned with respect to the fuel injection pump mounting hole 8 and fastened to the end plate 2.
It is not limited to the assembly 11 and the handle member 13.

On the other hand, the measuring end of the dial gauge 30 attached to the side wall of the cylinder block before the cylinder head is attached is brought into contact with the top wall of the piston 31 of the first cylinder, and while reading the measurement value of the gauge 30, the crankshaft 3 is manually rotated, and the piston is rotated manually. The rotational position of the crankshaft 3 is set at the top dead center position of 31.

While holding the crankshaft 3 in this state, the dummy gear 22 is lightly pressed in the reverse clockwise direction to absorb the bumps of the multiple gears that are meshed, and then the end plate is aligned with the mark 21b formed on the tip surface of the plate portion 21a. Mark 2a is stamped on the upper edge of 2.

After that, the fuel injection timing setting device is attached to the fuel injection pump mounting hole 8 through bolts 9 by aligning the mark C made on the pump body with the mark 2a engraved on the upper end surface of the end plate 2,
Idle gear 7 and matching mark 7 on pump drive shaft B
a, D ₁ Pump gear D that matches and meshes with each other
is attached to the pump drive shaft B via a key not shown.

In this way, the pump gear D and the pump drive shaft B have the same tooth shape as the dummy gear 22.
is set in accordance with a predetermined rotational position of the crankshaft 3, and the fuel injection pump A is attached in alignment with a mark 2a made at a constant relative rotational angle to the rotational position of the pump drive shaft B. Therefore, even if there is some error in the machining accuracy of the drive force transmission system components from the crankshaft 3 to the pump drive shaft B for each product, the error can be absorbed and the fuel injection timing can be set consistently and with high precision. It is.

Furthermore, as a result, the machining accuracy of the driving force transmission system components is lowered, thereby improving production efficiency and reducing costs accordingly.

It goes without saying that the present invention can be applied to both in-line and distributed fuel injection pumps.

<Effects of the invention> As explained above, by using the fuel injection timing setting device according to the invention, the fuel injection pump can be installed while keeping the rotational position of the pump drive shaft constant in accordance with the predetermined rotational position of the crankshaft. As a result, it is possible to absorb machining accuracy errors in the drive power transmission system components from the crankshaft to the pump drive shaft, and to set the fuel injection timing with high precision without variation from product to product. Since the required value of processing accuracy can be lowered, production efficiency can be improved and costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view for explaining a conventional fuel injection pump assembly method, FIG. 2 is a perspective view for explaining a fuel injection timing setting method using a device according to the present invention, and FIG.
Figures A, B and C are a rear view, a vertical sectional view and a partial plan view of the above-mentioned device, respectively.
mark, 3... crankshaft, 3a... matching mark, 4... crank gear, 4a... matching mark,
5: cam gear; 5a: matching mark; 7: idle gear; 7a: matching mark; 8: fuel injection pump mounting hole; 11: first assembly; 12:
...Second assembly, 13...Handle member, 20...
...inner cylinder member, 21...outer cylinder member, 21a...plate portion, 21b...mark, 22...dummy gear, 22a...matching mark.

Claims (1)

[Scope of claim for utility model registration] The rotational driving force of the crankshaft 3 is transferred to a plurality of gears 4,
5, 7, and D to the pump drive shaft B of the fuel injection pump A.
The rotational positions of the gears 7 and D are determined by aligning the matching marks 4a, 5a, 7a and _D1 made on each gear 4, 5, 7 and D with a predetermined rotational position of the crankshaft 3, and , mark C for positioning the fuel injection pump A with respect to the fuel injection pump mounting hole 8 formed in the end plate 2 on the engine body side.
In an internal combustion engine, the dummy gear 22 is formed in the same tooth shape as the pump gear D fixed to the end of the pump drive shaft B, and has a matching mark 7a, and the dummy gear 22 is fixed. At the same time, an outer cylinder member 21 integrally provided with a plate portion 21a provided with a matching mark 21b, an inner cylinder member 20 that rotatably supports the dummy gear 22 and the outer cylinder member 21, and the predetermined position of the crankshaft 3. At the rotational position, each gear 4, 5, 7 is positioned and engaged, and after the fuel injection pump A is installed, the gear 7 that is engaged with the pump gear D and the dummy gear 22 are aligned so that the alignment marks 7a, 22a are aligned. With the two meshed together,
Fastening members 11 and 13 that position the inner cylinder member 20 with respect to the fuel injection pump mounting hole 8 and fasten it to the end plate 2 in a detachable manner, the fastening members 11 and 13 Inner cylinder member 2
0 is positioned and fastened, a mark 2a is placed on the end plate 2 at a position corresponding to the mark 21b of the plate portion 21a, and the mark 2a and mark C are aligned to form the fuel injection pump mounting hole 8. 1. A fuel injection timing setting device for a fuel injection pump for an internal combustion engine, characterized in that the fuel injection timing of a fuel injection pump A attached to the engine is set.