JPH045704Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention corrects a control error in the fuel injection amount that occurs due to an error in the mounting position of the fuel injection pump and governor device when they are assembled into an engine. To provide an adjustment device for reducing the pump discharge rate error between the rated rack position and the maximum rack position due to torque rise, and which can be adjusted to improve the torque accuracy and output accuracy of the engine. .

To further explain in detail the application field of the technology that is the premise of the present invention, for example, as shown in FIG. 1, an engine E is provided with a fuel injection pump 1 and a governor device, A fuel injection amount adjustment rack 5 is slidably inserted into the rack groove 4 of the fuel injection amount adjustment device 3, and the rack 5 and the output section 6 of the governor device are interlocked and connected, and the rack 5 is received from the increase side by the stopper 7 to adjust the fuel injection amount to a predetermined value. By adjusting the adjustment device 10 of the governor device with the governor device positioned at the easy position,
This invention relates to a structure in which the control position of the rack 5 by the governor device is adjusted to a predetermined fuel injection amount position.

<Background> As shown in FIG. 3, the injection amount characteristic of a fuel injection pump is designed to be a reference characteristic curve a, but an error range b occurs due to manufacturing errors of the pump.

Further, as shown in FIG. 1, for example, in an electronic governor device for an engine, a pump housing 13
When the fuel injection pump 1 and the output part (actuator) 6 of the governor device are assembled, the rack position detection value of the rack position detector 12 attached to the actuator 6 will be incorrect due to the error in the mounting position. It deviates slightly from the actual position.

As a way to measure the value of this deviation, the easy 5
is positioned at a predetermined rack position, the output rod 17 of the actuator 6 is brought into contact with the rack 5, and the deviation of the detection value of the detector 12 from the actual position of the rack 5 is measured.

By correcting the measured deviation value by adjusting the adjusting device 10, the rack position detection signal of the detector 12 is corrected to a value indicating the actual position of the rack 5, which is then fed back to the electronic control circuit 32.
The actuator 6 can now control the rack 5 to the correct position.

<Prior Art> Conventionally, as a means for positioning the rack 5 at a predetermined rack position when measuring the deviation value of the rack position detection, a stopper is fixed to a gear case fixed to the pump housing so as to be adjustable with a screw. As shown in Fig. 4, the pump is set so that it is received at a stop position d, which is slightly on the side of increasing the amount of fuel compared to the starting operation position c, and the injection amount of the fuel injection pump is adjusted to the reference characteristic curve a at this stop position d. I was adjusting.

The reason why this stop position d is determined is that the stopper is located outside the restricted movement area e of the rack in order to prevent it from interfering with the controlled movement of the rack.

<Problems to be solved by the invention> Incidentally, it is important to ensure that the engine can accurately obtain the set rated output during rated operation.

However, in the above prior art, the rack is positioned and adjusted at the stop position d, which is far away from the rated operating position f, so as shown in FIG. Since the error width g is large, the error width of the engine's rated output increases proportionally.

In addition, the stopper attached to the gear case,
It is difficult to adjust the stop position of the fuel injection pump with high precision by adjusting the screw, and errors are likely to occur and it is time-consuming.

The purpose of the present invention is to eliminate the margin of error g in the injection quantity characteristics near the rated operating position f, and to make the operation for that purpose simple and efficient.

<Means for Solving the Problems> In order to achieve the above object, the present invention, for example, as shown in FIG. 1 or 2 and 5,
A stopper receiving surface 8 is provided on the pump body 3 so as to intersect with the rack groove 4, and the stopper 7, which is movable outside the rack movement area, is configured to be receivable on the stopper receiving surface 8, and is received on the stopper receiving surface 8. The present invention is characterized in that the stopper 7 is configured to receive and position the rack 5 at the rack position f when the engine E is rated for operation.

<Operation> First, the fuel injection pump 1 and the actuator 6 are assembled and fixed to the pump housing 13. Before or after this assembly, the stopper receiving surface 8 is made to receive the stopper 7, and this stopper 7 is made to receive the rack 5. At this time, the rack 5 is received by the stopper receiving surface 8 provided on the pump body 3 via the stopper 7, so that it is accurately positioned at the rated operating position f shown in FIG. (Adjust the injection amount of the fuel injection pump 1 so that it matches the reference characteristic curve a).

Next, the output rod 17 of the actuator 6 is brought into contact with the rack 5, and the detected value of the detector 12 is measured to determine how much it deviates from the actual rated rotational position f of the rack 5. 10
The rack position detection signal of the detector 12 is corrected to a value indicating the actual position of the rack 5, and is fed back to the electronic control circuit 32. Based on this, the actuator 6 can control the rack 5 to the correct position.

As a result, as shown in FIG. 5, the error width g at the rated operating position f, which arises from the error range b of the injection amount characteristics, becomes 0, and the error width at positions in this vicinity is also small.
The error width i at the torque limit position h where the torque rises during overload is also sufficiently small.

Finally, by removing the stopper 7 from the stopper receiving surface 8, the rack 5 is allowed to move freely in the restricted movement area e. This completes the assembly of the fuel injection pump 1 and the governor device to the engine and the adjustment of the injection amount, after which the engine can be operated.

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

That is, the error width g at the rated operating position f arising from the error range b of the injection amount characteristics of the fuel injection pump was a large value as shown in FIG. As shown in FIG. 5, the value becomes 0 or a small value close to 0, so the margin of error in the rated output of the engine can be almost eliminated.

Moreover, the error in the injection amount at the torque limit position close to the rated operating position can also be reduced.

In addition, when positioning the rack at the rated operating position f, the stopper is simply received by the stopper receiving surface fixed to the pump body, and there is no need for screw adjustment as in the conventional technology, resulting in high precision. Moreover, positioning can be done easily and efficiently.

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

FIG. 1 is a schematic system diagram of a fuel injection amount adjusting device for a fuel injection pump, and FIG. 2 is a plan view of a main part taken along the - line sectional view in FIG. A pump 1 is housed therein, and the fuel injection pump 1 is interlocked with a fuel injection camshaft 14 .

The pump housing 13 has an actuator 6 attached to its left side and a pressure rod 16 attached to its right side via a return spring 15.
While the right end of the fuel adjustment rack 5 is pressed to the fuel decreasing side B by a press rod 16, the left end is smoothly slid to the fuel increasing side A by an output rod 17 of the actuator 6.

The actuator 6 has a permanent magnet 1 at the center of the axis.
8 is fixed, and a moving coil 19 is externally fitted onto the moving coil 19 so as to be able to slide from side to side.
A rack position sensor 12 is attached to the upper side wall to detect the rack position.

The rack position sensor 12 has a slider 20 extending outward from the moving coil 19 of the actuator, and a variable resistor 21 made of conductive resin.
The position is detected by moving the object along the .

On the other hand, the accelerator sensor 11 that detects the rotation speed of the accelerator lever 23 and the rotation speed sensor 24 that detects the engine rotation speed are each connected to an electronic control circuit 32, and the electronic control circuit 32 is interlocked with the actuator 6. The rack position sensor 12 is connected to the electronic control circuit 32 via the rack position adjustment device 10 to form a minor loop.

The oil pressure sensor 25 and water temperature sensor 26, which detect abnormal drops in lubricating oil pressure and cooling water, are linked to the electronic control circuit 32 via a monitor lamp 27, so that if an abnormality in oil pressure or water temperature occurs, The actuator 6 is operated to move the rack 5 to a no-injection position K (see FIG. 5).

On the other hand, a stopper fitting hole 30 is formed perpendicularly to the rack groove 4 into which the rack 5 is fitted, and a rectangular parallelepiped-shaped stopper 7 is brought into contact with the right end wall thereof as a stopper receiving surface 8, so that the rack pin 31 is inserted into the stopper fitting hole 30. The rack 5 is set so that it comes into contact with the left edge 7a of the rack 5 at the rated operating position f.

To describe the function of the fuel injection amount adjusting device thus constructed, when the output rod 17 of the actuator 6 is gradually moved to the fuel increasing side A against the elastic force of the press rod 16, as shown in FIG. Next, let's move rack 5 sequentially through the no-injection position K, then to the no-load position L, the rated operating position f (corresponding to the rack position 11 mm), the torque limit position h (corresponding to the rack position 12 mm), and the starting operating position c. However, since the stopper 7 is attached at the rated operating position f, the rated position f is the upper limit and the flow does not move to the increasing side A any further.

Therefore, at this time, the actual position of the rack 5 is at the rated position f, so the value detected by the rack position sensor 12 is changed to the value corresponding to the rated position (i.e., the value shown in FIG. The rack position adjusting device 10 is corrected so as to match the value (to give a specific value of 11.0 mm).

As a result, the value detected by the rack position sensor 12 matches the value at the location where the rack is actually located, and is also fed back to the electronic control circuit 32, so that the actuator 6 can position the rack 5 in the correct position. can be controlled.

Incidentally, if this adjustment of the rack position is performed by the monitor lamp 27 of the abnormality detection element, and when the value from the sensor matches that from the rack, the lamp 27 is turned on. , adjustment operations can be performed easily and quickly.

Therefore, according to the above operation, the rated operating position f
The injection amount characteristics of the pump 1 can be adjusted to the reference characteristic curve a, centering on It is possible to secure a value close to this.

When this fuel adjustment is completed, the stopper 7 is removed from the rack groove 4 so that the rack 5 can move freely within the controlled movement area e.

On the other hand, FIG. 6 shows another embodiment of the present invention, in which elongated holes 41 are formed at four locations in a U-shaped stopper receiving plate 40, and the stopper receiving plate 40 is inserted through setscrews 43. It is fastened so as to be movable from side to side while being bridged over the rack groove 4 of the fuel injection pump.

Then, the inner end surface of the U-shaped open groove of the stopper receiving plate 40 is used as the stopper receiving surface 8, and the stopper 7 that fits and slides in the rack groove 4 is fixed to the stopper receiving surface 8. and a stopper 7 are configured to be movable together, and after adjusting the stopper 7 to a predetermined rated rack position f, the stopper receiving plate 40 is fixed to the fuel injection pump 1 with a set screw 43.

In the embodiment thus constructed, after adjusting the fuel injection amount, the stopper receiving plate 40 is inserted into the elongated hole 41.
By simply sliding the rack along the starting operation position c to the increase range beyond the starting operation position c, the rack 5 can be moved freely within the restricted movement range e, and the stopper 7
No need to worry about putting on and taking off.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a schematic system diagram of a fuel injection amount adjusting device for a fuel injection pump, FIG. 2 is a plan view of the main part taken along the - line cross section of FIG. 1, and FIG. Figures 5 to 5 are pump characteristic curve diagrams;
FIG. 6 is a front view of the main parts around the fuel injection pump showing another embodiment. 1...Fuel injection pump, 3...Pump body, 4
... Rack groove, 5 ... Fuel injection amount adjustment rack,
6... Output section, 7... Stopper, 8... Stopper receiving surface, 10... Adjustment device, E... Engine, f...
...Rack position during rated operation.

Claims (1)

[Scope of Claim for Utility Model Registration] An engine E is provided with a fuel injection pump 1 and a governor device, and a fuel injection amount adjusting rack 5 is slidably inserted into a rack groove 4 of a pump body 3 of the fuel injection pump 1, By interlocking and connecting the rack 5 and the output part 6 of the governor device, and adjusting the adjusting device 10 of the governor device with the rack 5 received from the increasing side by the stopper 7 and positioned at a predetermined rack position, the governor device In the fuel injection amount adjustment device for an engine fuel injection pump configured to adjust the control position of the rack 5 to a predetermined fuel injection amount position, a stopper receiving surface 8 is provided on the pump body 3 in a manner that intersects with the rack groove 4, The stopper 7, which is movable outside the rack movement area, is configured to be received by the stopper receiving surface 8, and the stopper 7, which is received by the stopper receiving surface 8, moves the rack 5 to the rack position when the engine E is rated for operation. 1. A fuel injection amount adjusting device for a fuel injection pump of an engine, characterized in that the device is configured to receive and position the fuel injection pump at a position f.