JP2903178B2 - Engine fuel injection amount adjustment device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to an apparatus having a fuel injection device called a unit injector in which a fuel injection pump and a nozzle are integrated.

2. Description of the Related Art In an engine having a unit injector,
In addition to a drive mechanism for driving a unit injector mounted on the cylinder head, a fuel adjustment mechanism for connecting the governor to a fuel control rack of the unit injector is provided. FIG. 3 shows a main part of such an engine.

In the drawing, a cylinder head 2 installed on the upper surface of a cylinder block 1 has a combustion chamber 3 in the cylinder block 1.
A unit injector 4 is inserted from above and attached. A rocker arm 8 for driving the unit injector 4 is supported by a shaft 9 inside the rocker case 7 above the cylinder head 2 surrounded by the rocker case 5 and its bonnet 6. The upper end of the push rod 10 penetrating the cylinder block 1 in the vertical direction abuts on one end of the rocker arm 8, and the tappet 11 also abuts on the lower end of the push rod 10. It is in contact with shaft 23. Below the rocker arm 8, an L-shaped interlocking lever 14 is pivotally supported by a stay 13 fixed to the upper surface of the cylinder head 2. One end of the interlocking lever 14 is connected via a turnbuckle 21 to a fuel control rack 15 projecting from the unit injector 4, and the other end is substantially parallel to the push rod 10 and extends through the cylinder block 1. It is connected to the upper end of the rod 16. Similarly, the lower end of the control rod 16 is connected to a governor lever 18 on a lever shaft 17 arranged in parallel with the cam shaft 23 in the cam shaft chamber 12. One end of the lever shaft 17 is supported by a side wall of the camshaft chamber 12 in the direction of the camshaft 23, is connected to a governor (not shown) outside the cylinder block 1, and also has an intermediate wall 19 in the camshaft chamber 12. It is supported so as to penetrate an axial stay 24 fixed to the outer side surface with bolts 22. And
A cover 20 is attached to the side opening of the camshaft chamber 12 so as to cover the lever shaft 17 and the camshaft 23.

In the above-mentioned conventional structure, the operation of the governor is controlled by the lever shaft.
17, the governor lever 18, the control rod 16 is transmitted to the fuel control rack 15 via the interlocking lever 14 and the turn buckle 21, whereby the fuel injection amount is adjusted to keep the engine at the set number of revolutions. It is necessary to adjust the positional relationship between the governor and the fuel control rack 15 to finely adjust the fuel injection amount.
Conventionally, this adjustment is performed by adjusting the length of the turn buckle 21. As can be seen from the figure, the turn buckle 21 is located below the rocker arm 8 inside the rocker case 7. Therefore, in order to perform this adjustment, it is necessary to open the bonnet 6 and remove the rocker arm 8. However, it is necessary to perform the fine adjustment at the time of assembling while observing the exhaust temperature and the exhaust color while operating the engine, and there is a disadvantage that such adjustment is impossible if the rocker arm 8 is removed. .

Therefore, in order to eliminate such inconvenience, Japanese Patent Laid-Open No.
As described in Japanese Patent Publication No. 1, at a connecting portion between the interlocking lever 14 and the control rod 16 which is laterally below the lower part of the rocker arm 8, a screw sleeve externally fitted to the upper end of the control rod 16 is attached to the interlocking lever 14. It is considered that the interlocking lever 14 is relatively rotated with respect to the control rod 16 by being screwed into a screw hole and rotating the screw sleeve.

According to the invention described in the above publication, since the adjustment portion is located laterally below the rocker arm 8, adjustment can be performed only by opening the hood cover 6 and inserting a tool. There are advantages. However, in this conventional structure, since the screw sleeve is screwed to the end of the interlocking lever 14, a snap ring for stopping the screw sleeve from moving in the longitudinal direction is required. The overall structure is complicated, and the screw sleeve is likely to rotate during the operation after the adjustment, resulting in a problem in reliability.

Means for Solving the Problems The technical means of the present invention for solving the above-mentioned problems includes an upper end of a control rod 16 which is connected to a governor side at a lower side thereof and which is disposed in a vertical direction. In a fuel injection device in which a fuel adjusting member 15 arranged on the cylinder is connected via an interlocking lever 14 also arranged above the cylinder head 2, the control rod 16
Adjust the upper end of the adjustment screw 42 inserted into the connection lever 37 on the upper end.
It is screwed to the tip of the interlocking lever 14 and exposed to the upper side of the interlocking lever 14, and a spring 45 is provided between the interlocking lever 14 and the connecting lever 37 to maintain a space between the interlocking lever 14 and the connecting lever 46. It is characterized by wearing.

In the configuration of the present invention, when the adjusting screw connected to the upper end of the control rod is rotated, the interlocking lever relatively rotates, thereby changing the relative position between the interlocking lever and the control rod, The fuel injection amount is adjusted.

Embodiment FIG. 1 is a front view showing only an interlocking lever 14 arranged at the same position as that of FIG. 3 and a connecting portion between the interlocking lever 14 and another member. Is mounted on a stay 13 on the upper surface of the cylinder head 2 via a shaft 31 so as to be rotatable in a vertical direction. One end 32 of the interlocking lever 14 projecting directly above the shaft 31
33 to the fuel control rack 15
34 projects obliquely upward in the opposite direction to the fuel control rack 15. In the joint 46 at the upper end of the control rod 16 extending upward toward the other end 34, as shown in FIG. 2, a connection hole 35 having an inner peripheral surface formed in a spherical shape is formed so as to penetrate in the horizontal direction. A spherical body 36 having a pair of opposed flat portions is rotatably fitted into the connecting hole 35. Further, the lower end of the connecting lever 37 is in contact with one of the opposing flat surfaces of the spherical body 36, and is integrally fixed by a bolt 38 and a nut 39 inserted through the spherical body 36 and the connecting lever 37. A vertically extending through-hole 41 whose center line P passes through the center of the sphere 36 is formed in a large head 40 at the upper end of the connecting lever 37, and an adjusting screw 42 is inserted into the through-hole 41 from below. Have been. The upper end of the adjusting screw 42 is screwed into a vertical guide screw hole 43 formed at the other end 34 of the interlocking lever 14 so as to project above the interlocking lever 14 and to be exposed. nut
44 is screwed. Further, a groove 47 for locking a tool such as a driver is formed in the protruding end. A support spring 45 is interposed between the interlocking lever 14 and the head 40 of the connecting lever 37 to maintain a distance between the interlocking lever 14 and the connecting lever 37.

In the above, the interlocking lever 14 has a support spring 45 and a nut
At 44, it is held so as to operate integrally with the control rod 16. Then, the adjustment screw 42 is rotated by a screwdriver or the like to adjust the injection amount to a predetermined value, and then held so as not to rotate, and locked by tightening the nut 44 with a tool such as a spanner. For example, when the adjustment screw 42 is rotated leftward from the groove 47 side, the interlocking lever 14 relatively rotates clockwise in the drawing against the force of the spring 45 and rotates in the opposite direction. In this case, it rotates counterclockwise, whereby the relative position with respect to the control rod 16 changes, and the fuel injection amount is adjusted. Such adjustment can be performed only by opening the bonnet 6 in FIG. 3 and inserting a tool from above.

According to the present invention, the fuel injection amount is adjusted at the connection between the control rod and the interlocking lever, so that unlike the conventional turnbuckle, the rocker arm does not need to be removed, and the engine is operated. There is an effect that it can be performed while performing. In addition, a conventional snap ring for stopping the screw sleeve is not required, the structure is simple as a whole, and there is little danger that the screw sleeve will be disturbed by rotation during operation like a screw sleeve, and the reliability is excellent.

[Brief description of the drawings]

FIG. 1 is a front view of an interlocking lever portion showing an embodiment of the present invention, FIG. 2 is an enlarged vertical sectional side view of a connecting portion between a lever and a control rod, and FIG. FIG. 2 ... Cylinder head, 14 ... Interlocking lever, 15 ... Fuel control rack, 16 ... Control rod, 37 ...
... Connection lever, 42 ... Adjustment screw, 44 ... Nut, 45 ...
Spring.

Claims (1)

(57) [Claims] 1. An upper end of a control rod 16, which is connected to the governor at a lower end thereof and disposed vertically, and a fuel adjusting member 15 disposed above the cylinder head 2, are also disposed above the cylinder head 2. In the fuel injection device connected via the interlocking lever 14, the upper end of the adjusting screw 42 inserted into the connecting lever 37 at the upper end of the control rod 16 is screwed to the tip of the interlocking lever 14, and the interlocking lever is
14. An engine characterized in that a spring 45 is provided between the interlocking lever 14 and the connecting lever 37 and is maintained between the interlocking lever 14 and the connecting lever 46 so as to be exposed to the upper side.