JPS6120302Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a mounting structure for a fuel injection pump of an internal combustion engine, a valve arm lubrication pump, a fuel feed pump, etc., which are mounted on the shaft end of a camshaft that drives an intake/exhaust valve tappet.

The camshaft is a long shaft that spans the entire longitudinal width of the internal combustion engine, and from the viewpoint of processing and assembly, it is not possible to further process each end of the camshaft to provide a pump shaft. As a result, each end of the cam shaft protrudes, and the pump shaft is connected thereto via an end nut or the like as a coupling device. If the centers of the camshaft and pump shaft do not match when they are connected, problems will occur such as the pump shaft being bent or the splines of the coupling ring becoming flat.
Conventionally, as shown in the conventional drawing shown in FIG.
A centering guide bush 3 is attached to the end nut 22.
Insert and loosely fit the pump shaft 24 through the shaft 24, fix the engaging body 29 to the shaft 24 with a pin 29a to transmit rotation, fit the engaging body 29 into the slot 22a of the end nut 22, and apply the driving force. It had a complex structure that conveyed the following.

In the present invention, an alignment jig is provided and the pump mounting base is fixed after complete alignment. With this structure, the centers can be perfectly aligned, so if the knock pin hole of the knock pin 25a for positioning the pump mount is provided at that position, there is no need to perform centering when fixing the pump mount afterwards. It is.

The purpose of the present invention is as described above, and the structure of the present invention will be explained based on the structure of the embodiment shown in the attached drawings.

FIG. 1 is a front sectional view of a diesel engine among internal combustion engines.

Place the cylinder block 1 on the base plate 2, and place the cylinder head 3 on the upper end of the cylinder block 1.
The valve arm chamber 4 is placed on the top of the cylinder head 3.
is covered. A valve arm 17 is provided within the valve arm chamber 4 so as to be movable up and down, and a push rod 18 is periodically pushed up through a tappet connected to the cam of the cam shaft 11 of the valve arm 17. The other end of the valve arm 17 is in contact with the upper end of the intake/exhaust valve 16, and the intake/exhaust valve 16 moves up and down within the cylinder head 3 to supply air into the combustion chamber and exhaust combustion gas. A fuel injection valve 15 is fixedly installed in the center of the intake/exhaust valve 16 and injects pressurized oil sent from a fuel injection pump 12 driven by a cam of a camshaft 11 into the combustion chamber. The combustion chamber is composed of a cylinder liner 10, a piston 9, and the bottom surface of the cylinder head 3, and the cylinder liner 10 is fitted and fixed into the cylinder block 1.

The piston 9 is connected to the crankshaft 7 by the connecting rod 8.
It is connected to the connecting rod bearing part of the bearing via a bearing metal. A bearing portion of the crankshaft 7 is provided to protrude from the base plate 2. The crankshaft is placed on the bearing, and the metal cap is covered and tightened to form the bearing of the crankshaft 7. A lubricating oil strainer 19 is fixedly installed on the bottom surface of the base plate 2, and concentrates the lubricating oil from each bearing portion of the crankshaft 7 into a lubricating oil pipe 20.

Cooling water enters the cooling water jacket formed by the gap between the outer peripheries of the cylinder block 1 and the cylinder liner 10 from the central cooling water pipe 14 on the side of the cylinder block, cools the cylinder liner 10 and the cylinder head 3, and then flows to the cooling water outlet. The collecting pipe 13 leads to the cooling device. 6 is a central supply air pipe, 5
is the exhaust manifold, 21 is the cylinder head 3
This is a cylinder head bottle for fixing the bottle on the top of the cylinder block 1. In such an internal combustion engine, the present invention aims to make the cylinder block 1 compact, lightweight, and highly rigid.

FIG. 2 is a side sectional view of the valve arm lubrication pump A, which is the main part of the present invention, mounted on the camshaft. Figure 3 is also a horizontal sectional view. Figure 4 is a front view. FIG. 5 is a front view when the rotational direction of the camshaft is reversed. A pump mounting body 25 is fixed to the side surface of the cylinder block 1, and a pump shaft 24 is bearing-supported on the pump mounting body 25 via a needle bearing.

A pump body 26 is attached to the outer surface of the pump mounting base 25.
is fixedly installed, and a trochoidal rotor 27 rotates inside the pump body 26. pump shaft 24
A tachometer drive device 28 for driving a tachometer on the instrument panel is provided at the outer end of the tachometer. An oil seal mounting body 25b in which an oil seal is fitted is fitted to the inner end of the pump mounting base 25. A spline 24a is cut into the inner end of the pump shaft 24, and the spline 24a and the inner spline of the end nut 22 mesh with each other. A play must be provided in the engagement of the splines 24a, and it cannot be said that the core is protruding just by spline fitting, and the splines 24a will play when rotated. Therefore, in order to fit with extremely less play than that of the spline fitting, an alignment jig 23 with tight fitting tolerances is fitted to the outer periphery of the pump shaft 24 with tight tolerances, and one is also attached to the outer periphery of the end nut. The fit is made to tight tolerances for perfect alignment.

The camshaft 11 is threaded onto an end nut 22.

As shown in Fig. 3, the suction hole 26a and the discharge hole 26b are opened in the left and right side directions of this trochoid type valve arm lubricating pump A, so that even when the engine is stopped, the lubricating oil is kept under the rotor 27 of the trochoid pump. Since the lubricating oil is stored in half, the lubricating oil can reach the valve arm immediately as the camshaft rotates.

4 and 5 are side views when the rotation of the pump shaft is reversed, and shows the suction hole 26a and the discharge port 26.
b is left and right reversed. Reference numeral 28 denotes a tachometer drive device, which is connected to the tachometer on the instrument panel by a wire.

FIG. 6 is a side sectional view showing a method of mounting a conventional camshaft-mounted pump. FIG. 7 is a view along the line C--C in FIG. 6. FIG. 8 is a front view of FIG. 6. FIG. 9 is a sectional view taken along the line DD in FIG. 6. FIG. 10 is a cross-sectional view taken along the line E--E in FIG. 6, and FIG. 11 shows a case where the rotational direction of the camshaft is reversed.

An end nut 22 is screwed onto the tip of the camshaft 11, and a slot 22a is provided at the outer end of the end nut 22. An engaging body 29 is fitted into the slot 22a to transmit rotation. Engagement body 2
9 is shown in a rear view in FIG.
While aligning the centers of the pump shaft 24, the pump shaft is fitted into the centering guide bushing 30 in order to connect it to the camshaft, and then the centering guide bushing 30 is fitted into the inner hole of the end nut 22 to perform centering. It's on. A is a gear pump type valve arm lubricating pump, which pumps lubricating oil by meshing gears 33 and 34. The gear 33 is connected to the pump case 3 by the shaft 32.
1 is supported by a bearing.

The pump case 31 is fixed to the pump mounting base 35 from the inside with bolts. Pump mounting stand 35
A fuel feed pump B is attached to the tip of the pump mount 35, and safety valves 36 and 37 are attached to the upper and lower parts of the pump mounting base 35. The fuel feed pump B is constituted by a trochoid pump, and a rotor 40 is installed inside a pump chamber formed by a pump case 38 and a pump lid 39, and is rotated by a pump shaft 24. A tachometer drive device 28 is provided at the outer end of the pump shaft 24 .
Suction hole 38a and discharge port 3 of fuel feed pump B
8b is open in the left-right direction. The inlet port 35a of the valve arm lubrication pump A is located on the side of the pump mounting base 35.
The discharge port 35b is opened on the upper surface.

FIGS. 10 and 11 are cross-sectional views of the oil passages of the discharge port 35b and suction port 35a of the valve arm lubrication pump A when the rotation direction is reversed. The pump mounting base 35
An oil passage is connected to the inside of the pump case 31 of the valve arm lubrication pump A inside the cylinder block 1.

As described above, the present invention is designed to attach a pump shaft such as a valve arm lubricating pump or a fuel feed pump to the shaft end of the camshaft 11 that drives the fuel injection pump or intake/exhaust valve tappet of an internal combustion engine. In a configuration in which the end nut 22 is screwed on and the inner spline of the end nut 22 and the spline 24a of the pump shaft 24 are fitted to be used as a coupling for both shafts, the outer periphery of the pump shaft 24 has a spline fitting. Alignment jig 23 with tight fitting tolerances
and the end nut 22 of the alignment jig 23.
The side is also fitted to the outer periphery of the end nut 22 with tight fitting tolerances, and the alignment jig 23 is used to align the camshaft 1.
1 and the pump shaft 24, the knock pin hole of the knock pin 25a for positioning the pump mounting base 25 is drilled in the cylinder block 1, so that the following effects are achieved. .

First, conventionally, when two shafts were connected by a coupling and made to rotate at the same time, it was difficult to perfectly align the shaft centers. An Oldham joint as described in Japanese Patent No. 32325 was inserted to prevent problems during rotation even if there was a misalignment between the two connected shafts.

However, the configuration of the Oldham joint is complicated,
Manufacturing costs were also high. In the present invention, by interposing the centering jig 23 between the two, it is possible to perfectly center the two, and the structure of the two-shaft connecting portion can be simplified.

Second, by performing complete centering of both shafts, the pump shaft 24 may be deflected and the spline 24a may be worn unevenly, such as when the pump shaft 24 is rotated through an Oldham joint without the shaft centers aligned. does not occur.

[Brief explanation of the drawing]

Figure 1 is a front cross-sectional view of a diesel engine among internal combustion engines, Figure 2 is a side cross-sectional view of the valve arm lubrication pump A attached to the camshaft, Figure 3 is a horizontal sectional view of the valve arm lubrication pump, and Figure 3 is a horizontal sectional view of the valve arm lubrication pump A. Figure 4 is the same front view, Figure 5 is a front view when the rotation direction of the camshaft is reversed, Figure 6 is a drawing showing how to install a conventional camshaft-mounted pump, and Figure 7 is C of Figure 6. -C line arrow view, FIG. 8 is a front view of FIG. 6, FIG. 9 is a DD cross-sectional view of FIG. 6, FIG. 10 is an E-E cross-sectional view of FIG.
FIG. 11 is a cross-sectional view taken along the line E--E in FIG. 6 when the rotational direction of the camshaft is reversed. 1...Cylinder block, 11...Camshaft,
22... End nut, 23... Alignment jig, 24
...Pump shaft.

Claims (1)

[Scope of utility model registration request] In order to attach a pump shaft such as a valve arm lubrication pump or a fuel feed pump to the shaft end of the camshaft 11 that drives the fuel injection pump or intake/exhaust valve tappet of an internal combustion engine,
An end nut 22 is screwed onto the end of the camshaft 11, and the inner spline of the end nut 22 and the pump shaft 2
In the configuration in which the spline 24a of No. 4 is fitted and used as a coupling for both shafts, an alignment jig 23 with a tighter fitting tolerance than the fitting of a spline is fitted to the outer periphery of the pump shaft 24. The end nut 22 side of the alignment jig 23 is also fitted to the outer periphery of the end nut 22 with tight fitting tolerances, and after aligning the axes of the camshaft 11 and the pump shaft 24 with the alignment jig 23, the pump is installed. A driving device for a camshaft-mounted pump for an internal combustion engine, characterized in that a knock pin hole for a knock pin 25a for positioning a stand 25 is formed in a cylinder block 1.