JPH0633793A - Vibration noise preventing device for gear case of engine - Google Patents

Abstract

PURPOSE:To suppress vibration noise of a gear case front wall by bringing it into contact with a point end surface of an idle gear shaft, and fixing the gear case front wall to a cylinder block by a fixing tool inserted through the gear case front wall and the idle gear shaft. CONSTITUTION:A timing gear transmitting device is provided in the front side of a cylinder block 2 of an engine and covered with a gear case 30, and its peripheral wall is fixed to the cylinder block 2. A front wall 31 of the gear case 30 is brought into contact with the front end face of an idle gear shaft 15 of the timing gear transmitting device, and a fixing tool 18 is inserted through the front wall 31 and the idle gear shaft 15, to fix the front wall 31 rigidly mounted to the cylinder block 2 through the idle gear shaft 15. In this way, vibration of the front wall 31 is suppressed to prevent a noise according to the vibration. Necessity for the conventional vibro-isolating rubber is eliminate to reduce a number of part items.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing vibration noise of an engine gear case.

[0002]

2. Description of the Related Art An apparatus of this type is disclosed in Japanese Utility Model Laid-Open No. 53-113904, which is proposed by the present applicant.
For example, it has a basic structure as shown in FIGS. That is, the timing gear transmission 11 is provided on the front side of the cylinder block 2 of the engine, the timing gear transmission 11 is covered with the gear case 30, and the peripheral wall of the gear case 30 is fixed to the cylinder block 2 so that the gear case 30 The idle gear shaft 15 of the idle gear 14 of the timing gear transmission 11 is fixed to the cylinder block 2 with a fixture 18.

In the conventional example, as shown in FIG. 3, the front wall 31 of the gear case 30 is fixed to the idle gear shaft 15 by a fixing tool 18b via a vibration-proof rubber 19, and the gear case 3
The front wall 31 of 0 was prevented from vibrating and generating noise. It is considered that the vibration noise of the gear case front wall 31 is mainly generated by the vibration of the cylinder block 2 and the air pulsation in the gear case 2.

[0004]

The above-mentioned prior art has the following problems because it has the structure in which the anti-vibration rubber 19 is interposed when fixing the front wall 31 of the gear case 30 to the idle gear shaft 15. I. The anti-vibration rubber 19 is excellent in that it blocks vibrations transmitted through the idle gear shaft 15. However, the anti-vibration rubber 19 is effective against vibrations caused by air pulsation in the cylinder block 2 and the gear case 2. Since 19 itself elastically vibrates, it is not always sufficient in terms of suppressing vibration noise of the gear case front wall 31. B. Further, since the anti-vibration rubber 19 is interposed, the number of parts is increased and the labor for assembling is increased, resulting in a high manufacturing cost as a whole. The present invention has been made in consideration of such circumstances, and the above-mentioned a. The technical issue is to solve the problems of B.

[0005]

In order to solve the above-mentioned problems, the means adopted by the present invention is the above-mentioned basic structure, in which the front wall 31 of the gear case 30 is brought into contact with the tip end surface of the idle gear shaft 15, The fixing tool 18 is made to penetrate through the gear case front wall 31 and the idle gear shaft 15, and the front wall 31 of the gear case 30 is rigidly fixed to the cylinder block 2 via the idle gear shaft 15. It is what

[0006]

The present invention operates as follows with the above construction. When fixing the front wall 31 of the gear case 30 to the cylinder block 2 via the idle gear shaft 15,
The fixture 18 of the idle gear shaft 15 is a gear case front wall 31.
And the idle gear shaft 15 are penetrated and they are fixedly fastened to the cylinder block 2 by joint tightening. As a result, against the vibration caused by the air pulsation in the cylinder block 2 and the gear case 2, the front wall 3 of the gear case can be made easier than the conventional example.
Further suppress the vibration noise of 1. Further, the anti-vibration rubber 19 of the conventional example becomes unnecessary.

[0007]

EFFECTS OF THE INVENTION The present invention has the following effects due to the above configuration and operation. I. Vibration of the gear case front wall 31 can be further suppressed, and noise can be prevented more effectively. B. In addition, since the anti-vibration rubber 19 of the conventional example can be eliminated,
As a result, the number of parts and labor of assembly can be reduced, and the manufacturing cost can be reduced.

[0008]

Embodiments of the present invention will now be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional plan view of essential parts of a vibration and noise suppression device for a gear case according to the present invention, and FIG. 2 is a front view of the gear case. In these drawings, reference numeral 4 is a crankshaft, 5 is a fuel injection pump, 8 is a lubricating oil supply port, and 1 is
Reference numeral 1 is a gear transmission, and 20 is a governor device.

The vibration and noise prevention apparatus for a gear case according to the present invention has the same basic structure as the conventional example. That is, a timing gear transmission 11 is provided on the front side of the cylinder block 2 of the engine, and the timing gear transmission 11 is attached to the gear case 3
0, the peripheral wall of the gear case 30 is fixed to the cylinder block 2, and the front wall 31 of the gear case 30 is connected to the idle gear shaft 15 of the timing gear transmission 11 via the idle gear shaft 15.
It is configured to be fixed to the cylinder block 2 with a fixture 18.

The timing gear transmission 11 has a front wall 3 of the cylinder block 2 as indicated by a chain line in FIG.
The drive gear 12 is fixed to the more protruding crankshaft 4, the feed pump gear 13 and the idle gear 14 are rotated by the drive gear 12, and the valve gear cam gear 17 and the pump drive gear 22 of the fuel injection pump 5 are rotated by the idle gear 14. Is configured to rotate. The idle gear 14 is rotatably supported by an idle gear shaft 15.

As shown in FIGS. 1 and 2, in the gear case 30, the front wall 31 is brought into contact with the tip end surface of the idle gear shaft 15, and the fixture 18 is connected to the gear case front wall 31 and the idle gear shaft 15. The front wall 31 of the gear case 30 through the idle gear shaft 15 and the cylinder block 2
It is configured to be rigidly fixed to. The gear case 30
Is formed of an aluminum material, and the bearing portion of the idle gear shaft 15 is lubricated by a lubricating means which will be described later. Therefore, the lubricity of the contact portion between the boss of the idle gear 14 and the gear case front wall 31 is ensured. Has been done.

As described above, the front wall 31 of the gear case 30 is
Is rigidly fixed to the cylinder block 2 via the idle gear shaft 15, the vibration of the front wall 31 of the gear case 30 can be further suppressed, and the noise accompanying the vibration can be further prevented.
Further, since the anti-vibration rubber 19 of the conventional example can be omitted, it is possible to reduce the number of parts and the assembling work to reduce the manufacturing cost.

A governor device 20 which is operated by the timing gear transmission 11 is provided on the front lateral side of the cylinder block 2, and the governor device 20 is provided on the front lateral side of the cylinder block 2 with respect to the gear case 30. It is provided in a governor housing 35 that constitutes a machine wall portion. In the drawings, reference numeral 21 is a pump drive shaft, 23 is a governor weight provided on the pump drive gear 22, 24 is a governor sleeve, 25 is a fork lever, 26 is a governor spring, 27 is a governor lever, and 28 is a speed governor. The lever 29 is an engine stop lever.

A communication passage 16 for lubricating oil penetrates through the idle gear shaft 15 in the axial direction thereof, and a thick rib 32 of the gear case front wall 31 has an in-case lubricating oil passage 33.
Are formed. When the idle gear shaft 15 is fixed to the cylinder block 2, the lubricating oil communication passage 16 communicates with the lubricating oil passage 6 formed in the thick wall portion 3a of the cylinder block front wall 2 to form a bearing portion. It lubricates and communicates with the in-case lubricating oil passage 33 of the gear case 30. The end of the in-case lubricating oil passage 33 faces the governor 20 device in the governor housing 35, and is formed as an oil injection port 34 in the machine wall 36 thereof.

According to this embodiment, from the oil injection port 34 formed in the machine wall 36 of the governor housing 35,
Lubricating oil is jetted to directly lubricate the governor 20 device in the governor housing 35. As a result, the contact portions of the governor weight 23, the governor sleeve 24, the fork lever 25, etc. can be sufficiently moistened and wear durability can be improved. The position of the oil injection port 34, which should be formed in the machine wall 36 of the governor housing 35, is set to the governor 2 to be lubricated.
It is desirable that the opening be formed so as to face the position where the lubricating effect is best, depending on the form of the device.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view of a vibration / noise prevention device for a gear case according to an exemplary embodiment of the present invention.

FIG. 2 is a front view of the gear case according to the embodiment of the present invention.

FIG. 3 is a cross-sectional plan view of essential parts of a vibration noise prevention device for a gear case according to a conventional example.

FIG. 4 is a front view of a timing gear transmission according to a conventional example.

[Explanation of symbols]

2 ... Cylinder block, 11 ... Timing gear transmission, 14 ... Idle gear, 15 ... Idle gear shaft, 18 ... Fixing device, 30 ... Gear case,
31 ... Front wall of gear case.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Hayatani 64 Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Sakai Co., Ltd.

Claims (1)

[Claims] 1. A timing gear transmission (11) is provided in front of a cylinder block (2) of an engine, and the timing gear transmission is provided.
(11) is covered with a gear case (30), the peripheral wall of this gear case (30) is fixed to the cylinder block (2), and the gear case (3
0), the idle gear shaft (1
In a vibration noise suppression device for an engine gear case configured by fixing 5) to a cylinder block (2) with a fixture (18), a front wall (31) of the gear case (30) is attached to a tip of an idle gear shaft (15). The front wall (31) of the gear case (30) is made to contact the surface, and the fixture (18) is penetrated through the gear case front wall (31) and the idle gear shaft (15), and the front wall (31) of the gear case (30) is idled. A vibration noise suppression device for an engine gear case, characterized in that it is rigidly fixed to a cylinder block (2) via a shaft.