JPH03512Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a fuel injection device for a diesel internal combustion engine, and in particular, an advance device is disposed between a fuel injection pump and a governor that controls the injection amount thereof. The present invention relates to a fuel injection device that is compactly arranged on a camshaft driven by an internal combustion engine to achieve miniaturization.

[Technical background of the invention and its problems] Conventionally, in a diesel engine fuel injection system using an in-line injection pump, the injection timing of the injection pump is set at one end of the camshaft that drives the in-line injection pump. An advance angle device is provided to control the fuel injection, and a flyweight part of a centrifugal governor is provided at the other end to control the fuel injection amount.The advance angle device and the governor are provided separately on both sides with an injection pump sandwiched on the camshaft. was.

For this reason, the entire fuel injection device is arranged along the camshaft, increasing its overall length, and creating space behind the injection pump for installing engine parts such as the oil fill, oil pump, level gauge, and engine auxiliary equipment. It was difficult to secure.

Note that the engine fuel injection pump drive device proposed in Japanese Utility Model Application Publication No. 57-61165 has a governor installed on the camshaft between the fuel injection pump and the advance timer, so maintenance of the governor is not necessary. When doing so, it is necessary to remove the advance angle timer.
Another disadvantage is that the camshaft is lengthened to ensure a stroke for swinging the governor lever that outputs the engine speed, resulting in a longer overall length.

[Purpose of the invention] The present invention was created in view of the above-mentioned problems and to effectively solve them.

The purpose of this invention is to achieve miniaturization of the entire injection device as much as possible, especially in a fuel injection device using an in-line fuel injection pump, so that it can be easily installed in automobiles, industrial machines, etc. The object of the present invention is to provide a fuel injection device that can perform the following steps.

[Summary of the invention] The present invention is a fuel injection system for a diesel engine that controls the amount of fuel injected and its injection timing according to the engine speed. Preferably, a fuel injection pump is provided, and a rod is supported at one end of the camshaft so as to be able to reciprocate in the axial direction from the one end to output the engine speed, and the movement of the rod is controlled by a link mechanism. A governor is provided to control the injection amount of the pump by transmitting the information, and an advance device is provided on a camshaft between the governor and the pump to control the injection timing of the pump,
This aims to achieve the above objectives.

[Embodiment of the invention] A preferred embodiment of the invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, the main body 1 of the fuel injection device
The system includes an in-line fuel injection pump 2 that measures, compresses and injects fuel into the engine, a centrifugal governor 3 that controls the fuel injection amount of the injection pump according to the engine speed, and a centrifugal governor 3 that controls the injection timing. It mainly consists of an advance angle device 4 that controls according to the engine speed.

The fuel injection pump 2 injects fuel into each cylinder of the engine using individual plungers 5, 5, 5. The illustrated example shows a pump for three cylinders, and the fuel injection pump 2 has plungers 5, 5, 5 that compress fuel. and cams 6, 6, for operating the plungers 5, 5, 5,
6 are provided in the same number as the number of cylinders in the engine, and they are arranged to operate according to the combustion order of each cylinder. The pumps 6 are each provided on a coaxial camshaft 7, and a gear train 8 is connected to the camshaft 7 to transmit engine rotation and drive the engine. For example, in the case of a 4-cycle engine, a gear train 8 is connected It is configured to be rotated at half the rotation speed of the shaft 9. Further, the fuel injection pump 2 is provided with a mechanism for metering the amount of fuel to be injected.
The amount is adjusted by rotating the plungers 5, 5, 5 with a control rack 10, thereby changing the compression stroke of the plungers 5, 5, 5.

A centrifugal governor 3 is connected to the control rack 10 in order to control the injection amount of the injection pump 2 according to the engine speed. It is provided on the one end portion 11 side. This governor 3 detects the engine speed using the centrifugal force of the flyweight 12,
The lift amount of the fly weight 12 at the point where the biasing force of the governor spring 13 and this centrifugal force are balanced is transmitted to the control rack 10 via the link mechanism 14 to control the fuel injection amount. .

The injection pump 2 also has a camshaft 7 corresponding to the rotation of the crankshaft 9 in order to control the injection timing.
An advance angle device 4 is provided which gives a phase difference to the rotation of the engine according to the engine speed. In this example,
A centrifugal advance device 15 is used in this advance device 4, and is provided as a rotating member 16 on the camshaft 7 between the fuel injection pump 2 and the governor 3 of the camshaft 7. The cam gear 17 of the gear train 8 transmits the engine speed to the cam gear 17 of the gear train 8. That is, as shown in the figure, a centrifugal advance device 15
The engine rotation speed is detected by the centrifugal force of the flyweight 18, and the contact point of the follower 19 that contacts the cam surface (not shown) formed on the flyweight 18 is determined by the centrifugal force of the flyweight 18 and the timer. By moving it to a position where the biasing force of the spring 20 is balanced, a phase angle difference is created between the drive side outer sleeve 21 on which the cam gear 17 is formed and the inner sleeve 22 engaged with the camshaft 7. It is configured to control the injection timing.

In the present invention, an advance angle device 4 is provided on the camshaft 7.
The rotating member 16 of the governor 3 and the flyweight 12 of the governor 3 are installed in parallel. Specifically, the fly weight 12 of the governor 3 is connected to the advance angle device 4.
The outer sleeve 2 on the driving side that constitutes the rotating member 16 of
1 and is fixed by a tightening nut 23 screwed onto the tip of the camshaft 7. A sleeve 24 is provided at the end of the camshaft 7 and is engaged with the flyweight 12 and moved in the axial direction of the camshaft 7 according to its centrifugal force, and the movement of the sleeve 24 is transmitted to the link mechanism 14. Ru. The sleeve 24 is formed with a rod 25 for guiding its movement. It is inserted into and supported in a guide hole 26 formed in 7 so as to be able to reciprocate.

In other words, in the present invention, the advance device 4 is attached to the camshaft 7 that drives the injection pump 2, and the flyweight 12 of the governor 3 is attached to the advance device 4, so that the advance device 4 is moved between the fuel injection pump 2 and the governor 3. An angle device 4 is provided, and an advance angle device 4 and a governor 3 are arranged in series. Therefore, the overall length of the main body 1 of the fuel injection device is shortened, and the entire body 1 is miniaturized. In particular, the other end of the camshaft 7 that drives the fuel injection pump 2 is free, so when the injection device main body 1 is installed in a diesel engine or the like, an oil filter or
Sufficient installation space can be secured for engine parts such as the oil pump, level gauge, engine auxiliary equipment, etc., and these can be easily installed.

Also, a governor 3 is provided at one end of the camshaft 7, which outputs the engine rotational speed in the axial direction from the camshaft 7 to control the injection amount.
Therefore, maintenance of the governor 3 is easy, and there is no need to remove the governor 3 when maintaining the advance angle device 4.

The present invention is based on the link mechanism 14 of the centrifugal governor 3.
As shown in FIG. 2, the link mechanism 14 is connected to the spring 27 from the fixed side.
It may be energized by. In the embodiment shown in FIG. 2, the advance device 4 is of an open type, but the advance device 4 does not have to be a mechanical centrifugal advance device, and the camshaft As long as it has a rotating member 16 that rotates integrally with the fuel injection pump 7, it may be of a hydraulic type, an electric type, or the like, and the in-line type fuel injection pump 2 may also be of a single-cylinder type.

[Effects of the invention] In summary, the present invention provides the following excellent effects.

(1) By arranging the advance angle device and the governor in parallel at one end of the camshaft that drives the fuel injection pump, the main body of the fuel injection device can be made as compact as possible.

(2) The main body of the fuel injection system has been made as compact as possible, so there is sufficient space for installing engine parts such as the oil filter, oil pump, level gauge, etc. and engine auxiliary equipment installed near the injection pump. , it becomes possible to install them easily.

(3) Since the governor is provided at one end of the camshaft, maintenance of the governor and advance device is easy.

[Brief explanation of the drawing]

FIG. 1 is a schematic side sectional view showing a preferred embodiment of the fuel injection device according to the present invention, and FIG. 2 is a schematic side sectional view showing a modification thereof. In the figure, 1 is the main body of the fuel injection device, 2 is the fuel injection pump, 3 is the governor, 4 is the advance device, 7 is the camshaft, 11 is one end of the camshaft, 12 is the flyweight of the governor, and 25 is the rod. It is.

Claims (1)

[Scope of utility model registration request] In a fuel injection device for a diesel engine that controls the amount of fuel injected and its injection timing according to the engine speed, a fuel injection pump is provided on a camshaft rotationally driven by the engine, and a fuel injection pump is provided to be driven by the camshaft. , a rod is supported at one end of the camshaft so as to be able to reciprocate in the axial direction from the one end and outputs the engine rotational speed, and the movement of the rod is transmitted to a link mechanism to control the injection amount of the pump. A fuel injection device comprising: a governor for control; and an advance device for controlling injection timing of the pump, provided on a camshaft between the governor and the pump.