JPH0447394Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The purpose of this invention is to provide an electronically controlled governor for diesel engines that is easy to maintain, has high response sensitivity, and has excellent accuracy. do.

<<Prior Art>> Conventionally, an electronically controlled governor for a diesel engine configured so that the pump housing can also be used as a mechanical governor device is equipped with a rack pin 45 on the control rack of the fuel injection pump 44, as shown in FIG. The tip 52 of a fork lever 51, which is fixed to the inner end of the pivot shaft 46 by inserting the pivot shaft 46 through a pivot hole 48 provided in the fixed wall 47, is engaged with the rack pin 45.

On the other hand, an operating lever 43 is fixed to the outer end of the rotation shaft 46, and this operating lever 43 is connected to the pump chamber 4.
Solenoid 41 and tension spring 42 installed outside
The control rack pin 45 of the fuel injection pump 44 is adjusted via the rotation shaft 46 and the fork lever 51 to adjust the fuel injection amount and adjust the engine operating speed. was beginning to be controlled.

In addition, in conventional electronically controlled governor devices that do not use link mechanisms, etc., as shown in Japanese Patent Application Laid-Open No. 53-4123, a solenoid is fixed to one side of the linear movement direction of the rack of the fuel injection pump. Some solenoid operating shafts act on control racks.

In this conventional technology, a solenoid is fixedly protruded laterally outward from the housing of a fuel injection pump, one end of a control rack is inserted into the casing of the solenoid, and the operating shaft of the solenoid is connected via a connecting rod that is fitted and fixed to the tip of the rack. It is working. Then, a spring holding plate is fixed to the tip of the rack inside the solenoid casing, and a return spring is arranged between this spring holding plate and the inner wall of the casing on the pump housing side, and the pulling force of this return spring and the operating force of the solenoid are The control rack is controlled based on the difference in force between the two.

<<Problem to be Solved>> However, in the former conventional type, the rotation shaft 46 of the operating lever 43 is pivotally supported in a pivot hole 48 provided in a fixed wall 47 of the engine via an oil seal 49. In addition, the frictional force of the oil seal 49 prevents the operating lever 43 from smoothly swinging, and this frictional force also leaves hysteresis during operation, which deteriorates the responsiveness of the governor device and makes it difficult to control the engine speed. There was a problem that accuracy decreased.

On the other hand, in the latter conventional type, a holding plate is fixed to the tip of the rack inserted into the solenoid casing, and a return spring is arranged between this spring holding plate and the inner wall of the casing on the pump housing side. In addition to requiring a dedicated solenoid, it is time-consuming to assemble the solenoid and fuel injection pump.
It cannot be implemented cheaply. Moreover, in the latter case, a spring holding plate is fixed to the control rack, and the return spring acts on this spring holding plate, so there are many inclusions in the control mechanism, and rack position control errors are likely to occur due to assembly errors and processing errors. .

<Means for solving the problem> The present invention can be implemented at low cost by easily assembling the solenoid and fuel injection pump into the pump housing.
Although it is designed to facilitate maintenance, by directly driving the control rack of the fuel injection pump with the solenoid, the amount of movement of the control rack can be made to correspond accurately to the amount of operation of the solenoid. To do this, an opening is formed in the pump mounting wall of the pump housing that accommodates the fuel injection pump in the diesel engine, and the pump part of the fuel injection pump is inserted through this opening, and the fuel injection pump is attached to the pump mounting wall. Attachment: A solenoid of an electronic control device is removably fixed to the outer surface of one side wall of the pump housing that is perpendicular to the pump mounting wall, and a return spring is attached to the other side wall of the pump housing that faces this one side wall. The linear moving direction of the rack of the fuel injection pump is set perpendicular to the one side wall, and the operating shaft of the solenoid is set on one side of the rack's moving direction, and the push rod biased by a spring is placed on the other side. the pump housing between the operating shaft and the rack; An insertion hole is provided on one side wall,
Through this insertion hole, the actuating shaft is applied directly to the rack in a pressing manner, and the push rod is returned to the rack, and the spring force of the spring is applied in a pressing manner to reduce the difference between the pressing force of the operating shaft and the pressing force of the return spring. The invention is characterized in that it is configured to control the rack based on.

<Operation> In the present invention, the operating shaft of the solenoid acts directly on the control rack of the fuel injection pump, and the control rack is sandwiched between the operating shaft of the solenoid and the return spring. Since the push rod that is pressed and energized is easily applied in a pressing manner, there is no frictional resistance in the control rack drive system, and hysteresis does not occur due to the influence of frictional resistance when changing the operating direction, and the control rack is connected to the solenoid. It will move smoothly in accordance with the amount of operation.

Moreover, since the solenoid is removably fixed to the outer surface of the side wall of the pump housing and the actuating shaft acts directly in a pressing manner, the solenoid can be easily removed.

In addition, since the operating shaft of the solenoid and the push rod, which is biased by the return spring, act in a pressing manner with the rack of the fuel injection pump in between, the fuel injection pump can be refueled by simply removing the pressing force of both the operating shaft and the push rod. The injection pump is separated from the governor force generation mechanism, and the fuel injection pump can be easily removed from an opening formed in the pump mounting wall that is perpendicular to one side wall to which the solenoid is fixed.

《Example》 Fig. 1 shows a schematic front view of a vertical diesel engine.This engine 1 has a cylinder block 3 above a crankcase 2 forming a crank chamber R.
are integrally formed, and the cylinder block 3
The engine body E is formed by mounting and fixing a cylinder head 4 and a rocker arm cover 5 in this order on the upper part of the engine body.

A piston 8 is housed inside the cylinder block 3 and swings up and down via a connecting rod 7 as a crankshaft 6 rotates. Further, on both sides of the cylinder block 3, there are provided a valve train camshaft 9 and a fuel injection camshaft 10, which are driven from the crankshaft 6 via a transmission device (not shown).

The valve drive camshaft 9 pushes down the intake and exhaust valves 14 via the tappet 11, the push rod 12, and the rocker arm 13 in the rocker arm cover 5, and connects the combustion chamber 15 formed above the piston 8 and the intake and exhaust in the cylinder head 4. It communicates with port 16,
The fuel injection camshaft 10 operates a fuel injection pump 17 to forcefully feed fuel to a fuel injection nozzle 19 of a sub-combustion chamber 18 communicating with the combustion chamber 15.

The amount of fuel injected from the fuel injection nozzle 19 is controlled by an electronic control device 20 using a solenoid 2.
This is done by controlling the pump 1 and adjusting the rack 22 of the fuel injection pump 17.

The fuel injection pump 17, as shown in FIG.
An opening C is formed in the upper wall 23b of the pump housing 23, and the pump part is inserted through the opening C and fixed to the upper wall 23b.

The solenoid 21 is fixedly supported on a cylindrical mounting base 24 fixed to the outer surface of one side wall 23a of the pump housing 23, which is perpendicular to the upper wall 23b.

In this way, the solenoid 21 attached to the outer surface of the one side wall 23a of the pump housing 23 via the mounting base 24 has its operating shaft 25 passing through the insertion hole 26 formed in the one side wall 23a of the pump housing 23, and the operating shaft The tip of 25 is pump housing 2
3 and the rack 22 of the fuel injection pump 17
The rack 22 is brought into direct contact with the end face of the rack 22, and the rack 22 is operated to the fuel reduction side A by operating the solenoid 21 toward the advancing side. Further, a push rod 28 is in contact with the end surface of the rack 22 opposite to the end surface that the operating shaft 25 is in contact with, and this push rod 28 is connected to a return spring 2 disposed between the pump housing 23
7, the rack 22 is pushed out and biased towards the fuel increase side B.

Therefore, since the elastic force of the return spring 27 is always acting on the rack 22 of the fuel injection pump 17, when the operating shaft 25 of the solenoid 21 moves in and out, the elastic force of the return spring 27 causes the rack 22 of the fuel injection pump 17 to be fixed. 22
is moved to the fuel increasing side B, and the rack 22 comes to accurately follow the operating shaft 25 of the solenoid 21.

Note that this return spring 27 is attached to the push rod 2 on the rack 22.
8 acts in a pressing manner, the pressing force on the rack 22 can be easily removed by, for example, operating the push rod 28 to the fuel reduction side A from an operation port (not shown) provided in the pump housing 23. , the fuel injection pump 17 can be easily assembled and removed during maintenance.

In the insertion hole 26 through which the operating shaft 25 of the solenoid 21 passes, a guide 30 made of synthetic resin is interposed between the operating shaft 25 of the solenoid 21 and the operating shaft 25 to smooth the forward and backward movement of the operating shaft 25. be.

This insertion hole 26 is inserted into the fuel injection pump 1 when the pump housing is used in a mechanical governor device.
It can be used as the high idling device mounting hole 29 to prevent the rack 22 of No. 7 from hunting, and the pump housing 23 can be shared between a mechanical governor device and an electronic governor device. Therefore, it can be implemented at a lower cost.

A sealing means 31 consisting of an O-ring is provided between the cylindrical mounting base 24 of the solenoid 21 and each mounting surface S of the pump housing 23 and the solenoid 21, and this sealing means 31 prevents fuel injection within the pump housing 23. The lubricating oil used to lubricate the camshaft 10 is prevented from leaking out through the insertion hole 26 of the operating shaft 25 through the cylindrical hole space 32 of the cylindrical mounting base 24.

On the other hand, the lubricating oil leaking into the cylindrical space 32 flows back into the pump housing 23 through the oil return hole 33 formed in the cylindrical mounting base 24 and the gap between the bearing 34 that supports the fuel injection camshaft 10. I'm starting to do that.

Further, the operating shaft 25 of the solenoid 21 is provided with a rubber boot 35 that is extendable and retractable from the center thereof to the solenoid body.
This prevents the lubricating oil that has lubricated the fuel injection camshaft 10 from entering the inside of the solenoid 21 through the insertion hole 26 of the operating shaft 25 .

In place of the rubber boot 35, as shown in FIG. 3, a disc-shaped oil intrusion prevention plate 36 may be attached to the operating shaft 25 of the solenoid 21 to prevent oil from entering the solenoid 21. .

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

(1) Since the solenoid is configured to directly operate the control rack of the fuel injection pump, there are cases where the actuator and controller are installed separately from the engine, or where the rack is operated from the actuator via a link or crank. Although it can be implemented at a lower cost than the conventional governor, the mass of the reciprocating portion can be reduced and the responsiveness of the governor can be improved.

(2) In the operation of the rack, the operating shaft of the solenoid and the push rod act directly on the rack, which eliminates the cause of rattling, and also reduces the frictional resistance in the rack drive system, reducing hysteresis caused by frictional resistance. can be reduced and operate smoothly.

Moreover, since the actuating shaft and push rod are easily applied in a pressing manner, members for easily fixing them can be omitted, reducing the number of parts involved in the control mechanism and reducing assembly errors due to assembly and processing. .

Therefore, even in devices such as governor devices, where high precision cannot be achieved unless the slight movement stroke of the rack is accurately controlled, the response of the governor device can be achieved by accurately controlling the position of the rack. This improves the control accuracy of the engine governor, making it more stable.

(3) The operating shaft of the solenoid is placed on one side of the rack in the direction of movement so that it acts directly on the rack, and a push rod that is biased by a return spring is placed on the other side to press the rack. Therefore, the governor generating mechanism and the fuel injection pump can be easily separated by simply removing both pressing forces.

As a result, the fuel injection pump can be easily removed from the opening provided in the pump mounting wall of the pump housing in a direction perpendicular to the pressing force of the governor force generation mechanism, and it is also easy to assemble.
Maintenance of the fuel injection pump can be performed extremely easily.

(4) The solenoid located on one side of the rack is removably fixed to the outer surface of the side wall of the pump housing, and is configured so that it only applies pressure to the actuating shaft, so that the entire actuator is injected with fuel. The structure is independent from the pump and rack, so the actuator can be removed independently from the pump housing, making assembly and maintenance of the actuator extremely easy. Also, commercially available solenoids can be used, making it easy to use the governor. The cost of the force generation mechanism can be significantly reduced and can be implemented at low cost.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 is a front view schematically showing a vertical diesel engine, FIG. 2 is a cross-sectional view taken along the line -- in FIG. 1, and FIG. 3 is another embodiment. 2 is a view corresponding to FIG. 2, and FIG. 4 is a perspective view of main parts showing a conventional example. 17... Fuel injection pump, 21... Solenoid, 22... Rack, 23... Pump housing, 23a... One side wall of pump housing 23,
23b... Pump mounting wall, 25... Operating shaft, 26
...insertion hole, 27...return spring, 28...push bar,
C...opening.

Claims (1)

[Claims for Utility Model Registration] An opening C is formed in the pump mounting wall 23b of the pump housing 23 that accommodates the fuel injection pump 17, and the pump portion of the fuel injection pump 17 is inserted through this opening C to construct the fuel injection pump. 17 is attached to the pump mounting wall 23b, and the solenoid 21 of the electronic control device is removably fixed to the outer surface of one side wall 23a of the pump housing 23 that is orthogonal to this pump mounting wall 23b, and the A return spring 27 is attached to the other side wall of the pump housing 23, and the linear movement direction of the rack 22 of the fuel injection pump 17 is set in a direction perpendicular to the one side wall 23a. The operating shaft 25 of the solenoid 21 is returned to the other side by arranging a push rod 28 that is biased by a spring 27.
The rack 22 is positioned between the solenoid 21 and the return spring 27, and the operating shaft 25, the rack 22, and the push rod 28 are aligned in a straight line in the direction of movement of the rack 22, and the pump is connected between the solenoid 21 and the rack 22. An insertion hole 26 is provided in the side wall 23a of the housing 23, and the operating shaft 25 is inserted into the rack 2 through the insertion hole 26.
In addition to applying pressure directly to 2,
2, the push rod 28 is applied in a pressing manner by the spring force of the return spring 27, and the pressing force of the operating shaft 25 and the return spring 27 are
An electronically controlled governor for a diesel engine, characterized in that it is configured to control the rack 22 based on the differential force between the pressing force and the pressing force.