JPH02161164A - Fuel injection device - Google Patents

Abstract

PURPOSE:To dispense with the readjustment of fuel injection timing after the transporting and keeping of an engine by forming an internal combustion engine in such construction as a coupling block can be fixed to a gear case with a threaded bar after the fuel injection timing of a fuel injection device is properly adjusted. CONSTITUTION:When a fuel injection device 50 has been mounted on a test device after its assembly to adjust fuel injection timing, the mounting position of a gear case 90 is fixed at a position where a fixed proper fuel injection timing is obtainable, and a coupling block 75 is fixed by screwing a threaded bar 95. In addition to that, a timing mark is carved at a spot between a peripheral part of a flange 76 of the coupling block 75 and the gear case 90 under such conditions. In attaching any parts to an internal combustion engine thereafter, four bolts 85 to fix a gear 80 are loosened into a temporary tightening state, and the fuel injection device 50 is attached to the internal combustion engine using the tapped holes 94 of the gear case 90. Thus a gear on the internal combustion engine meshes with a gear 80 of the fuel injection device 50.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fuel injection device for internal combustion engines, particularly diesel engines.

[Prior Art] A fuel injection device installed in an internal combustion engine is shown, for example, in FIGS. 3 and 4, and the fuel injection device, which is generally designated by the reference numeral 1, has an injection pump main body 10 and an injection pump main body 10 that are rotatable. The pump is equipped with a camshaft 12 for driving the pump, a delivery valve 14, etc. arranged in the pump. camshaft 12
A cam is formed according to the number of cylinders in the internal combustion engine, and this cam pressurizes the fuel by pushing up the franchisor.
Fuel is force-fed from the delivery valve 14 to each cylinder via the high-pressure pipe 16, and is injected into the cylinder.

The tip of the camshaft 12 protrudes from the side wall 11 of the injection pump main body 10, and the protruding tip of the camshaft 12 is formed into a tapered portion 12a.
Attach the coupling block 25 using the The coupling block 25 is cylindrical and has a nut 18
A flange portion 26 is formed on the side of the coupling block 25 facing the injection pump main body 10, and the outer peripheral portion of the flange portion 26 is fixed to the camshaft 12 by the injection pump body 10. Carve out a mark to indicate this.

A gear 30 is fitted onto the opposite side of the flange 26 of the coupling block 25 and fixed with four bolts 35. This gear 30 drives the camshaft 12 by meshing with a gear that is linked to the crankshaft of the internal combustion engine.
It is necessary to match the meshing position with the gear on the internal combustion engine side. For this purpose, a mark 33 is engraved on the outer periphery of the gear 30,
Further, the bolt hole 32 through which the bolt 35 passes is made into a long hole so that the mounting angle of the gear 30 relative to the coupling block 25 can be adjusted.

Meanwhile, a gear case 20 that covers the coupling block 35 and the gear 30 is attached to the injection pump main body 10. This gear case 20 is attached to the injection pump body 1o with four bolts, and the bolt holes are elongated holes so that the angle at which the gear case 20 is attached to the injection pump body 10 can be adjusted.

Then, the fuel injection device 1 is fixed to the internal combustion engine using the bolt holes 22 formed in the flange portion of the gear case 20.

As shown in FIG. 4, a line OA connecting the axis of the plunger of the injection pump body 10 and the center 0 of the camshaft 1.2 connects the center O of the camshaft 12 and the bolt hole 22 for attaching the gear case 20 to the internal combustion engine. Assuming that the angle formed by the line OB is α, the angle α indicates the mounting attitude of the fuel injection device i\1 to the internal combustion engine, and the accuracy of the angle α represents the mounting accuracy of the fuel injection device.

If this accuracy is poor, problems such as damage to the high pressure pipe 16 will occur.

Next, a mark 33 engraved on the gear 30 that immediately moves the camshaft 12 indicates the injection timing of the injection pump.
If the angle formed by the line oC and the line OB connecting this mark 33 and the center ○ is β, the accuracy of the angle β indicates the accuracy of the fuel injection timing for the internal combustion engine, and if this accuracy is poor, the performance of the internal combustion engine will be impaired. .

If the angle formed by the line oC and the line OA is θ, the accuracy of the angle θ indicates the accuracy of the injection timing of the fuel injection device 1 itself,
The angle O is approximately ±1 depending on the processing accuracy and assembly accuracy of the component parts.
．． A variation of about 5 degrees occurs.

Therefore, in the conventional device shown in FIGS. 3 and 4, a peephole 23 is formed in the gear case 20, and the gear 30 is installed while checking the mark engraved on the flange 26 of the coupling block 25. Set the position to long hole bolt hole 32
is used to adjust and set the mesh with the gear on the internal combustion engine side.

In Japanese Patent Publication No. 56-12701, the present applicant fixed a coupling block attached to the camshaft of an injection pump to the injection pump body using a lock bin, and fixed the coupling block to the injection pump body when transporting the fuel injection device and installing it in an internal combustion engine. We have proposed a technology that prevents rotation of the camshaft and improves the efficiency of the connection work when connecting the camshaft and the gear on the internal combustion engine in an appropriate rotational positional relationship.

[Problems to be Solved by the Invention] In the conventional technology, it is difficult to simplify the work of simultaneously adjusting the accuracy of mounting the fuel injection device to the internal combustion engine and the accuracy of the timing of fuel injection.

Therefore, the present invention provides a device that eliminates the above-mentioned conventional problems.

[Means for Solving the Problems] The fuel injection device of the present invention includes a coupling block that is attached to the tip of a camshaft protruding from the injection pump body, and a mounting angle in the circumferential direction with respect to the coupling block that can be freely adjusted. It is equipped with a fixed gear and a gear case that covers the coupling block, and the gear case is fixed to the injection pump body so that the mounting angle in the circumferential direction can be freely adjusted. It has means for fixing the coupling block together.

[Operation] By having the above means, the present invention can fix the coupling block and maintain the adjusted state after adjusting the fuel injection timing. Then, when assembling the fuel injection device to the internal combustion engine, with the coupling fixed, simply adjust the mounting angle of the gear and mesh it with the gear on the internal combustion engine side to ensure proper fuel injection between the internal combustion engine and the fuel injection device. You can set the time.

[Example] Hereinafter, the present invention will be explained in detail using FIGS. 1 and 2.

FIG. 1 is a partially sectional front view showing an outline of the fuel injection device of the present invention, and FIG. 2 is a left side view. A camshaft 62, which is provided with a delivery valve 58 at the upper part and whose tip protrudes from the side wall 61 of the injection pump main body 55, is formed with a tapered part 62a, and a coupling block 75 is concentrically mounted using this tapered part 62a. Secure with nut 68.

A flange portion 76 is formed at the end of the coupling block 75 on the side of the injection pump body 55, and a timing mark is engraved on the outer periphery of the flange portion 76 as in the conventional case. 80 is fixed with four bolts 85. This gear 80 meshes with a gear on the internal combustion engine side to immediately operate the injection pump, but as shown in FIG. A circumferential gap is provided so that the attachment position of the gear 80 to the coupling block 75 can be adjusted in the circumferential direction.

A gear case 90 is attached to the injection pump main body 55 so as to cover the coupling block 75.

As described above, this gear case 90 is fixed to the injection pump body with four bolts, and by making the bolt holes elongated, the mounting angle of the gear 80 in the circumferential direction can be similarly adjusted.

This gear case 90 has a peephole 91 for visually checking the mark provided on the flange 76 of the coupling block 75.
It has a pedestal 92 and is provided with a screw hole 93 passing through the pedestal 92 in the radial direction. Screw hole 93
Screw on the screw 95 and tighten the screw 9 with the lock nut 98.
Perform positioning in step 5. The tip portion 95a of the screw stud 95 comes into contact with the outer peripheral surface 75a of the coupling block 75, and fixes the coupling block 75. Therefore, it is also effective to knurl or otherwise process the outer circumferential surface 75a of the coupling block 75 to increase the coefficient of friction between it and the tip 95a of the threaded rod 95.

Next, the operation of this embodiment will be explained.

After assembling the fuel injection device 50, it is attached to a test device to adjust the fuel injection timing, and the mounting position of the gear case 90 is fixed at a position where a predetermined appropriate fuel injection timing is obtained, and the threaded rod 95 is tightened to connect the coupling. Fix block 75. In this state, a timing mark is carved between the outer periphery of the flange portion 76 of the coupling block 75 and the gear case.

Thereafter, the fuel injection device 50 is handled during transportation, storage, etc., but during this period, the camshaft 62 is fixed together with the coupling block 75 and will not rotate inadvertently.

When attaching to the internal combustion engine, the four bolts 85 fixing the gear 80 are loosened and temporarily tightened, and the fuel injection device 50 is assembled to the internal combustion engine using the screw hole 94 of the gear case 90. After that, the gear on the internal combustion engine side and the gear 80 of the fuel injection device 50 are engaged, but the timing of the gear on the internal combustion engine side is set in advance, so the gear 80 is engaged in accordance with this gear, and the bolt 85 is fully inserted. By tightening it, the timing of the internal combustion engine and fuel injection system can be automatically set.

After completing a series of operations, remove the threaded rod 95 to unlock the coupling block 75, and open the threaded hole 93.
Attach a blind stopper to the tank and complete all work.

[Effects of the Invention] The present invention allows the mounting angle of the gear case attached to the side of the fuel injection pump body to be freely adjustable, and the gear case is provided with a threaded rod for fixing the coupling block integrated with the camshaft of the injection pump body. Therefore, by fixing the coupling block with a threaded rod after properly adjusting the fuel injection timing of the fuel injection device, the proper adjustment state can be maintained, and there is no need to readjust it after transportation or storage.

Furthermore, when assembling the fuel injection device to the internal combustion engine, the gear case is fixed to the internal combustion engine side with the coupling block fixed, and the temporarily tightened gear is rotated to mesh with the gear on the internal combustion engine side. After that, by fully tightening the bolts that secure the gear, the internal combustion engine and the fuel injection device can be easily connected. Since the interlocking timing between the two can also be set appropriately, the efficiency of the internal combustion engine is improved, and undue stress is not applied to the fuel injection device itself, resulting in improved durability.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional front view showing an embodiment of the present invention, Fig. 2 is a partially sectional left side view, Fig. 3 is a partially sectional front view showing a conventional device, and Fig. 4 is a left side view. It is. 1.50...Fuel injection device, 1.0.5
5... Injection pump body, 1.4,58.
...Delivery valve, 12.62...
...Camshaft, 25.75...
・Coupling block, 20.90・・・・・・・・・
・Gear case, 30.80...Gear, 93...Screw hole, 9
5・・・・・・・・・・・・・・・Threaded rod. Patent originator Nippondenso Co., Ltd. agent Patent attorney Meiki 8 Akira (2 others) No. 1
Figure 2

Claims (1)

[Claims] (1) In a fuel injection device that includes an injection pump body equipped with a plunger, a camshaft that drives the plunger, and a delivery valve installed above the plunger, a coupling block that is attached to the tip of the camshaft that protrudes from the injection pump body , a gear fixed to the coupling block so that its mounting angle in the circumferential direction can be freely adjusted, and a gear case that covers the coupling block, and the gear case can be adjusted in its mounting angle in the circumferential direction with respect to the injection pump body. What is claimed is: 1. A fuel injection device that is freely fixed to the coupling block and is provided with a threaded hole formed in the gear case and a threaded rod that is screwed into the threaded hole to fix the coupling block.