JPH03182678A - Fuel injection pump for diesel engine - Google Patents

Abstract

PURPOSE:To facilitate a coupling work by rotatably engaging a coupling with a pump drive shaft and intercoupling the two members through a joining means mounted to the coupling. CONSTITUTION:A second stationary plate 26 of a coupling 3 is rotatably engaged with a pump drive shaft 8, and coupled to a first stationary plate 25 mounted to a timer 2. When the timer 2 is coupled to a crank shaft, the crank shaft is brought into a proper crank angle position and the timer 2 and a pump body 1 are registered with each other by means of marks 19a and 19b. With this state, a cotter bolt 21 mounted to the second stationary plate 26 of the coupling 3 is fastened to intercouple the timer 2 and the pump drive shaft 8. The second stationary plate 26 is formed in the shape of an oblong, a slit 20 is formed in the lower part thereof, and the drive shaft 8 is fastened through fastening of the cotter bolt 21 crossing the slit. This constitution facilitates a work to intercouple the timer 2 and the pump drive shaft 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel injection pump for supplying fuel to a fuel injection nozzle in a diesel engine.

[Prior Art] As a conventional fuel injection pump, the one shown in FIG. 3 is known. This injection pump has a pump body 1, a timer 2 connected to a camshaft 7 within the pump body 1, and a coupling 3 attached to the timer 2.

Reference numeral 4 is an injection pipe connected to an injection nozzle (not shown), 5 is a governor that controls the rotation of the camshaft, and 6 is a feed pump for feeding fuel. be.

The timer 2 is connected to a pump drive shaft 8 by a coupling 3, and the pump drive shaft 8 is connected to a crankshaft 10 via a timing gear 9. The crankshaft 10 is rotationally driven by a piston (not shown) that is opened and moved by combustion of fuel. As shown in FIG. 4, for example, the timing gear 9 is controlled by a crankshaft gear 11, an idle gear 12, a cam gear 13, and an injection pump gear 4.

A camshaft 7 within the pump body 1 includes a timer 2, a coupling 3, a pump drive shaft 8. Then, it is opened and rotated by a crankshaft 10 via a timing gear 9. By this rotation of the camshaft 7, a plunger (not shown) disposed on one side of the camshaft 7 in the pump body i is reciprocated in the F right direction in the figure, and as a result,
Fuel is supplied from the injection pipe 4 to the individual injection nozzles. At that time, the timer 2 changes the reciprocating timing of the plunger according to the engine speed, and as a result,
The timing of fuel injection from the injection nozzle is adjusted according to the engine speed.

1-. In the fuel injection pump described above, the timing of fuel injection from the injection nozzle must correspond accurately to the crank angle of the crankshaft 10.

Therefore, conventionally, the coupling 3 is provided with a second fixing plate 15 and a second fixing plate 16, the first fixing plate 15 is fixed to the timer, and the second fixing plate 16 and the pump drive shaft 8 are connected by a key. Then, tighten the bolts 17 by tightening both rotating plates 15 and 16.
It was fixed by.

In this conventional device, since a key was used in the coupling 3, in order to make the key come to a predetermined position with respect to the first fixing plate 15, as shown in FIG. Timing marks 1, 8a and 18b were attached to the injection pump gear 14 in advance when it was first assembled.

I matched those marks.

However, even in this case, the pump drive shaft 8
] It is difficult to always accurately place the second key in a predetermined position (1'1.), and in many cases there are variations in the position. An elongated hole was drilled in either of the bolts 16 so that the positions of both rotating plates (5 and 16) could be adjusted relative to each other when the bolts 17 were tightened.

[Problems to be Solved by the Invention] As described above, in the conventional fuel injection pump, since a key was used in the coupling part, the timing gear 9
In some cases, it may be necessary to align the idle gear 12 and the injection pump gear 14, or both rotation plates 1
I had to adjust the position between 5 and 16 due to length.

In fact, 1-1 these tasks were extremely troublesome.

The present invention was made in view of the problems 1-1 in conventional devices, and by eliminating the use of a key in the coupling portion, connection with the crankshaft can be extremely easily performed. The purpose is to provide a fuel injection pump.

[Means for Solving the Problems] Part 1: In order to achieve the purpose, in the fuel injection pump according to the present invention, the coupling and the pump drive shaft are
7. The coupling is adapted to fit into the rotating self-made coupling, and the coupling is further provided with fastening means for tightening and fixing the pump drive shaft.

A bolt can be used as the fastening means.

E effect] According to the present invention, the fuel injection pump is connected to the crankshaft (10).
The following operations are performed to connect the

First, the timer (2) and therefore the plunger in the pump body (1) are set to a predetermined 41'li? with respect to the pump body (1). ?
Set to . In this case 1, for example, marks (], 9a,
The timer (2) can be set at a predetermined position by attaching the marks 19b) and aligning their marks when assembling the two.

On the other hand, the crankshaft (10) is centered at an appropriate crank angle position, for example, top dead center.

a coupling (3) fixed to the timer (2);
The pump drive shaft (8) connected to the crankshaft (10)
), but since they are mutually rotatable, the alignment of the timer (2) and the crankshaft (, 10) as described above are as follows:
Each can be performed individually.

When the positioning of both the timer (2) and the crankshaft (10) is completed, the fastening means (cotton bolt 21) provided on the coupling (3) is tightened, and the timer (
2) and the pump drive shaft (8>) are fixedly connected.

[Example] FIG. 1 shows a main part of an example of a fuel injection pump according to the present invention. The parts of the fuel injection pump according to this embodiment that are not shown in FIG. 1 may be the same as those shown in FIG. 3.

In FIG. 1, the fact that the timer 2 is attached to the pump main body 1 and the fact that the coupling 3 that connects the timer 2 and the pump drive shaft 8 has a first fixing plate 25 and a second fixing plate 26 are clearly explained. This is the same as the conventional device shown in FIG. What is different is the configuration of the second fixing plate 26 and the alignment marks 19a and 19b attached to the timer 2 and pump body 1.

As shown in FIG. 2, the second fixing plate 26 has a substantially rectangular shape, and a slit 20 is provided at the bottom of the second fixing plate 26, and a bolt 21 is inserted across the slit.
is screwed in.

As described above, when connecting the timer 2 of the injection pump to the crankshaft 10 (Fig. 3), first set the crankshaft 10 to an appropriate crank angle position, for example, the top dead center of the piston. , while timer 2
Align the mark 19a with the mark 19b on the pump body l. In this state, if the bolt 21 of the second fixing plate 26 of the coupling 3 is tightened, the timer 2 and the pump drive shaft 8 are connected.

According to this connection method, it is not necessary to align the marks 18a and 18b of the timing gear and to use the elongated hole in the coupling 3 as in the conventional device shown in FIG. 3, so the work becomes extremely simple. .

Note that the ml fixing plate 25 in the coupling 3 can be constructed from a so-called laminate plate. Thereby, transmission of vibration to the timer 2 can be reduced.

[Effect of the invention] According to the invention, the coupling (3) and the pump drive shaft (
8) are rotatably fitted into each other and the two are connected by the fastening means (21) provided on the coupling (3), so there is no need to connect them with a key as in the past. As a result, it has become possible to connect the two very easily.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a side view showing essential parts of an example of a fuel injection pump according to the present invention, FIG. 2 is a front view taken along the line n-■ in FIG. 1, and FIG. FIG. 4 is a side view showing an example of a conventional fuel injection pump, and FIG. 4 is a front view showing a timing gear in the conventional device. 9...Timing gear, 10...Crankshaft.

Claims (1)

[Claims] A fuel injection pump driven by a pump drive shaft connected to a crankshaft via a timing gear, comprising: a timer for adjusting the timing of fuel supply to a fuel injection nozzle; It has a coupling that connects the timer and the pump drive shaft, the coupling is fixed to the timer, and the coupling and the pump drive shaft are rotatably fitted to each other. A fuel injection pump for a diesel engine, characterized in that the coupling is provided with fastening means for tightening and fixing the pump drive shaft, thereby eliminating the need for a key.