JPS6029609Y2 - Engine idle gear lubrication system - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an engine idle gear lubrication device, the purpose of which is to use the pressure of lubricating oil to prevent the idle gear support shaft from rattling or dislodging in the axial direction. The purpose is to ensure that the idle gear always operates well.

The present invention will be explained below based on the drawings.

In FIG. 1a, which is a front view of a diesel engine,
1 is a gear case, and 2 is a crank case.

Figure 1b is a front view of the diesel engine with the gear case 1b removed and showing the meshing status of the gears.
In figure b, the gear case flange 1a is fixed to the front wall of the crankcase 2, and the outside of the gear case flange 1a includes a crank gear 3, an idle gear 4, a fuel injection pump cam drive gear 5, and an intake/exhaust cam drive. A gear 6 for driving an oil pump, a gear 9 for driving an oil pump, and the like are arranged.

The crank gear 3 is fixed to the crankshaft 7, and the idle gear 4 is rotatably fitted to the support shaft 8.
Gear 5 and gear 6 are fixed to camshaft 10 and camshaft 11, respectively, and mesh with idle gear 4, and pump drive gear 9 is fixed to pump shaft 9a and meshed with gear 5.

Each gear 3.4. Helical teeth are formed in 5.6.9.

Figure 2 shows the first gear with the gear case 1b attached.
This is an enlarged partial view of the ■-■ cross section of Fig. b. In this Fig. 2, the support shaft 8 is formed with a step 11 facing toward the crankcase 2 side, and the support shaft 8 is formed with a small diameter by the step 11. It is divided into a base end portion 13 and a large-diameter idle gear support portion 14.

The base end 13 of the support shaft 8 is connected to the support hole 1 of the crankcase 2.
6 in the direction of arrow A, and is locked to the front wall of the crankcase 2 at the stepped portion 11.

The idle gear 4 is rotatably fitted to the support portion 14 via a metal 17.

A recess 18 having a circular cross section is formed in the inner surface of the gear case 1b. An 01J ring 20 is fitted between the peripheral surface and the outer peripheral surface of the support shaft 8.

An oil chamber 21 is formed by the gear case side end surface 8a of the support shaft 8, the inner surface of the recess 18, and the recess 12 of the gear case 1b. Through channel 27 it communicates with an oil pump 30 (FIG. 1a).

A first lubricating oil passage 22 in the longitudinal direction of the support shaft 8 is provided in the support shaft 8;
A second lubricating oil passage 23 is formed perpendicular to the support shaft 8,
The first lubricating oil passage 22 opens toward the oil chamber 21, and the second
The lubricating oil passage 23 communicates between the fitting portion 32 of the idle gear 4 (metal 17) and the support portion 14, and the inner end of the first lubricating oil passage 22.

On the front wall portions of the gear case 1b and the crank case 2, which respectively face both end surfaces of the boss portion of the idle gear 4,
An oil groove 25 is formed, and the oil groove 25 communicates the fitting portion 32 of the support shaft 8 and the idle gear 4 with the inside of the gear case 1.

The lubricating oil that has been pressure-fed from the oil pump 30 and reached the oil chamber 21 is transferred to the first oil chamber 21. The lubricating oil enters the fitting part 32 through the second lubricating oil passages 22 and 23 and is used to lubricate the fitting part 32, then passes through the groove 25 and lubricates both boss end faces 33 and 34 of the idle gear 4. However, it escapes into the gear case 1.

The lubricating oil in the oil chamber 21 is applied to the support shaft 8 at a constant pressure as indicated by the arrow A.
Since the support shaft 8 is pressed in the axial direction, the support shaft 8 does not wobble in the axial direction, and the state of fixation (press fit) of the support shaft 8 to the crankcase 2 can be maintained well.

In particular, in the case of the idle gear 4 having helical teeth, the thrust load direction at the meshing point of the crank gear 3 (Fig. 1b) is opposite to the thrust load direction of the cam drive gear 5 and suction/exhaust cam drive gear 6 of the fuel injection pump. Therefore, a bending load acts on the support shaft 8, and when the engine speed increases and decelerates (for example, during engine braking), the thrust load switches, and the direction of the bending load on the support shaft 8 also changes. The spindle 8 has the effect of coming out in the opposite direction of arrow A due to the repeated replacement, but according to the present invention, the axial wobbling of the spindle 8, especially the pulling out in the opposite direction of arrow A, can be prevented reliably. It can be prevented.

As explained above, according to the present invention: (1) There is no fear that the support shaft 8 of the idle gear 4 will shake in the axial direction, and the idle gear 4 can always operate well.

That is, since the oil chamber 21 is formed by the gear case side end surface 8a of the support shaft 8 and the inner surface of the gear case 1b, the oil chamber 2
The pressure of lubricating oil 1 is applied to the support shaft 8 in the direction opposite to the direction of extraction (
Therefore, the support shaft 8 is prevented from shaking in the axial direction, and the idle gear 4 can always be operated satisfactorily by providing an appropriate press-fitting allowance for the support shaft 8.

In particular, it is extremely practical to apply the present invention to the idle gear 4 equipped with helical teeth that is subject to large changes in thrust load.

(2) It is easy to inspect and clean the oil chamber 21, lubricating oil passage 22, etc.

That is, the oil chamber 21 is formed between the inner surface of the gear case 1 and the gear case side end surface 8a of the support shaft 8, and the first lubricating oil passage 22 is open toward the gear case 1 side (oil chamber 21 side). The oil chamber 21 and the first lubricating oil passage 22 can be easily inspected and cleaned by simply removing the gear case 1.

[Brief explanation of drawings]

Figure 1a is a front view of a diesel engine to which the present invention is applied, Figure 1b is a front view with the gear case removed,
FIG. 2 is an enlarged partial cross-sectional view taken along the line ■-■ in FIG. 1b. 1a...Gear case flange, 1b...
・・Gear case, 2・・・・Crank case, 4・
...Idle gear, 8...Spindle, 8a.
... End face, 16 ... Support hole, 21 ...
...Oil chamber, 22.23...1st. Second lubricating oil path (lubricating oil path), 30...Oil pump.

Claims (1)

[Scope of utility model registration request] Press fit the support shaft with the idle gear rotatably fitted into the support hole in the front wall of the crankcase that opens inside the gear case, and form an oil chamber that communicates with the oil pump between the gear case side end surface of the support shaft and the inner surface of the gear case. A lubricating oil passage was formed inside the spindle from the oil chamber to the fitting part of the spindle and idle gear, so that the pressure of the lubricating oil in the oil chamber was applied to the spindle in the opposite direction to the direction of removal. An engine idle gear lubricating device characterized by: