JPH0330594Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a device for driving a fuel injection cam and a load device of a diesel engine, and the present invention is a device that drives a fuel injection cam and a load device of a diesel engine. The entire drive device is made smaller and simpler.

<Prior Art> In general, in diesel engines such as those used in tractors and vehicles, which require a wide operating rotation range, it is necessary to advance the fuel injection timing in accordance with the rotation speed of the diesel engine. For this reason, an automatic timer is provided at the tip of the fuel injection cam shaft rotatably supported on the pump housing of the fuel injection pump, and the automatic timer advances the fuel injection cam in accordance with the rotation speed of the fuel injection cam shaft. be.

On the other hand, when attaching a relatively small hydraulic pump to the engine, such as a power steering drive pump or a relatively small hydraulic pump for lifting and lowering work equipment, the hydraulic pump is often connected to the fuel injection camshaft and driven. When a hydraulic pump is driven by a fuel injection camshaft whose advance angle is controlled, the amount of advance of the automatic timer fluctuates due to changes in the load on the hydraulic pump, making it impossible to accurately control fuel injection timing.

Therefore, in the past, as shown in FIG.
6, one end of the hydraulic pump drive shaft 26 is interlocked and connected to the fuel injection camshaft 10 by a gear transmission 27, and a hydraulic pump 22 is attached to the other end, and the load fluctuation of the hydraulic pump 22 is controlled by an automatic timer. 17 so as not to affect it.

<Problems to be Solved by the Invention> In the configuration as described above, since the pump drive shaft is provided at a location away from the fuel injection camshaft, the entire drive device for both shafts becomes large in size.

Moreover, because of the automatic timer attached to the tip of the fuel injection camshaft, the gear case that houses the automatic timer protrudes far forward, resulting in a large engine.

Additionally, if you try to install a new automatic timer on an engine that is not equipped with a conventional automatic timer, you will have to create a new one because the shape of the pump housing will be significantly different. If it is formed integrally with the cylinder block, there is a problem in that the cylinder block must be redesigned, resulting in a very high cost.

This invention was proposed in view of the above problems.
The first purpose is to allow the automatic timer to accurately control the fuel injection timing regardless of the load on the load device, while still making the entire device compact. This allows an automatic timer to be easily installed even in engines that are not equipped with it.

<Means for Solving the Problems> In order to achieve the above object, the present invention, as shown in FIGS. Part 24
In addition, an automatic timer 17 is arranged, and the automatic timer 17 has a driven wheel 21 located in front of the main driving wheel 19, and an intermediate transmission shaft 9 that passes through the inside of the pump housing 5 back and forth to be rotatably supported. At the same time, its front end is interlocked and connected to the timing transmission wheel 14 of the timing transmission device 6, and the intermediate transmission shaft 9
The input shaft 23 of the load device 22 is interlocked to the rear end via the power transmission section 24, and the main drive wheel 19 of the automatic timer 17 is interlocked to the rear end, and the fuel injection camshaft 10 is formed into a cylindrical shape. The fuel injection camshaft 10 is fitted onto the intermediate transmission shaft 9 so as to be relatively rotatable, and the fuel injection camshaft 10 is fitted onto the driven wheel 21 of the automatic timer 17.
It is structured so that it is linked and connected to.

<Operation> When the timing transmission wheel 14 is rotationally driven, this rotation is transmitted to the input shaft 23 of the load device (hydraulic pump etc.) 22 and the main driving wheel of the automatic timer 17 via the intermediate transmission shaft 9, The device and automatic timer 17 are driven.

When the main driving wheel of the automatic timer 17 is rotated, the automatic timer 17 rotates the driven wheel 21 to the main driving wheel 1 by the amount corresponding to the rotation of the engine 1.
9, the fuel injection camshaft 10 fixed to the driven wheel 21 is advanced, and the injection timing of the fuel discharged from the fuel injection pump 4 is advanced.

At this time, the input shaft 23 of the load device 22 is interlocked and connected to the intermediate transmission shaft, and the load fluctuations occurring in the load device 22 are received by the intermediate transmission shaft 9 and the automatic timer 17 is not affected. It will not upset the angle device.

<Example> Hereinafter, an example of the present invention will be described based on the drawings.

Fig. 1 shows a longitudinal side view of the automatic timer section, and Fig. 2 shows a schematic plan view of a diesel engine.
A pump housing 5 to which a fuel injection pump 4 is attached is provided at the front of the side surface 2a of the fuel injection pump.

The timing case 3 is provided with a gear-type timing transmission 6, and the rotation of the crankshaft 7 is transmitted to the fuel injection pump drive shaft 8 which is pivotally supported by the pump housing 5 by the timing transmission 6. 2 It is designed to slow down and convey the message.

As shown in FIG. 2, the fuel injection pump drive shaft 8 consists of an intermediate transmission shaft 9 and a cylindrical fuel injection camshaft 10 that is fitted onto the intermediate transmission shaft 9 so as to be relatively rotatable.

The intermediate transmission shaft 9 has its front portion pivotally supported in a bearing hole 11 of the timing case 3 via a bearing 12, and a centrifugal ball governor 13 is incorporated in the portion that protrudes into the timing case 3. Timing transmission wheel 14
is installed.

Further, a rear portion of the intermediate transmission shaft 9 has a bearing 16 fitted into a bearing hole 15 of the pump housing 5.
is pivotally supported via a fuel injection camshaft 10,
An automatic timer 17 is attached to the rear end of the intermediate transmission shaft 9.

The automatic timer 17 is a timer housing 1 attached to the rear outer surface of the pump housing 5.
A main driving wheel 19 is assembled into the intermediate transmission shaft 9 and a centrifugal weight 20 is mounted on the front side of the main driving wheel 19.
The driven wheel 21 is spline-fitted to the rear end of the fuel injection camshaft 10.

A hydraulic pump (load device) 22 is attached to the outer surface of the rear wall of the timer housing 18.
The second input shaft 23 is operatively connected to the rear end of the intermediate transmission shaft 9 via a power transmission section 24 consisting of a gear transmission and a main drive wheel 19 of the automatic timer 17.

Incidentally, reference numeral 25 in the figure is an oil passage for lubricating oil supplied from a lubricating oil supply device not shown, and this oil passage 25
The sliding surfaces of the automatic timer 17, the intermediate transmission shaft 9, and the fuel injection camshaft 10 are lubricated with the lubricating oil supplied under pressure.

When the drive device for the fuel injection cam and the load device is configured as described above, the rotation of the crankshaft 7 is transmitted to the timing transmission wheel 14 via the timing transmission device 6.

The rotation transmitted to the timing transmission wheel 14 rotates the main driving wheel 19 of the automatic timer 17 and the input shaft 23 of the hydraulic pump 22 through the intermediate transmission shaft 9.

When the main driving wheel 19 of the automatic timer 17 is rotationally driven, the centrifugal weight 20 advances the driven wheel 21 relative to the main driving wheel 19 by an amount corresponding to the rotational speed of the engine 1, and the fuel injection camshaft 10 is advanced. be done.

On the other hand, the force that drives the hydraulic pump 22 varies greatly depending on whether the hydraulic pump 22 is working with the hydraulic oil that will be discharged from it, whether it is not working, the amount of work, etc. This changing driving force of the hydraulic pump 22 is applied to the main drive wheel 19 of the automatic timer 17.
The fuel injection camshaft 10 acts as a load on the engine 1, but does not act on the centrifugal weight 20 and the driven wheels 21 that advance the fuel injection camshaft 10.
The advance angle is always controlled correctly according to the rotation speed.

In the above embodiment, the timing transmission device 6 in the timing case 3 is a gear transmission device, but it is of course possible to use a timing belt transmission device.
The power transmission unit 24 to the hydraulic pump 22 is formed at the rear end of the intermediate transmission shaft 9 or the main drive wheel 19 of the automatic timer 17 instead of a gear type transmission, and the input shaft 23 of the hydraulic pump 22 is directly interlocked. You can do it like this.

Further, it is also possible to use a generator or a compressor as the hydraulic pump 22, which is a load device.

<Effects of the invention> Since the present invention is constructed and operates as described above, it has the following effects.

That is, since the timing transmission wheel drives the main drive wheel of the automatic timer and the input shaft of the load device via the intermediate transmission shaft, the fluctuating load of the load device causes the slave of the automatic timer to advance the fuel injection camshaft. It does not affect the driving wheels. In addition, since the power transmission section to the load device and the automatic timer are located on the rear side of the pump housing, there is no wasted space even if load devices of different sizes are attached. The fuel injection camshaft that advances the angle is fitted onto the intermediate transmission shaft so that it can rotate freely relative to the intermediate transmission shaft, and since the outer shape is one fuel injection camshaft, it is not necessary to separately install the fuel injection camshafts as in the conventional example. The installation space can be halved compared to those that do. This allows the drive device to be made smaller while allowing accurate control of fuel injection timing.

Furthermore, the pump housing is arranged on the side surface of the cylinder block so as to be connected to the timing case, and the power transmission section to the load device and the automatic timer are provided on the rear side of the pump housing. There is no need to protrude much forward, and the overall length of the engine can be shortened accordingly, making it more compact.

Furthermore, because the pump housing is arranged in a continuous manner with the timing case, and the fuel injection camshaft is fitted onto the intermediate transmission shaft, existing diesel engines that do not have a load device or an advance device on the fuel injection camshaft The engine can be converted into a diesel engine equipped with a load device and an automatic timer on the fuel injection camshaft by simply replacing the fuel injection camshaft.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, and FIG. 1 is a vertical sectional side view of the automatic timer portion;
FIG. 2 is a schematic plan view of the engine, FIG. 3 is a sectional view taken along the line of FIG. 1, and FIG. 4 is a diagram corresponding to FIG. 1 of the conventional example. DESCRIPTION OF SYMBOLS 1... Diesel engine, 2... Cylinder block, 2a... Lateral side of 2, 3... Timing case, 4... Fuel injection pump, 5... Pump housing, 6... Timing transmission, 9... ...intermediate transmission shaft,
10... Fuel injection camshaft, 14... Timing transmission wheel,
17... Automatic timer, 19... Main driving wheel, 21... Driven wheel, 22... Load device, 24...
...Power transmission section.

Claims (1)

[Claims for Utility Model Registration] 1 Cylinder block 2 of diesel engine 1
A timing case 3 is arranged in front of the cylinder block 2, a pump housing 5 is arranged in front of the side surface 2a of the cylinder block 2 so as to be connected to the timing case 3, and a fuel injection pump 4 and a fuel injection cam are arranged in the pump housing 5. A timing transmission device 6 is provided in the timing case 3, a load device 22 is interlocked and connected to the timing transmission device 6, and fuel is injected to the timing transmission device 6 via an automatic timer 17. In a diesel engine fuel injection cam/load device drive device configured by interlocking cams, a load device 2 is located on the rear side of the pump housing 5.
2, an automatic timer 17 is arranged, and the automatic timer 17 has a driven wheel 21 located in front of the main driving wheel 19, and an intermediate transmission shaft 9 that passes through the inside of the pump housing 5 back and forth. The intermediate transmission shaft 9 is connected to the input shaft 23 of the load device 22 at the rear end thereof to transmit the power. The main driving wheel 19 of the automatic timer 17 is interlocked and connected via the section 24, and the fuel injection camshaft 10 is formed into a cylindrical shape and fitted onto the intermediate transmission shaft 9 so as to be relatively rotatable, and the fuel injection is performed. A driving device for a fuel injection cam/load device of a diesel engine, characterized in that a camshaft 10 is interlocked and connected to a driven wheel 21 of an automatic timer 17. 2. The drive device for a fuel injection cam/load device for a diesel engine as set forth in claim 1, wherein the load device 22 is a hydraulic pump of a hydraulic device. 3. The driving device for a fuel injection cam/load device of a diesel engine as set forth in claim 1 or 2, wherein the timing transmission device 6 is a gear type timing transmission device.