JPH0861355A - Plain bearing device - Google Patents

Abstract

PURPOSE: To prevent the deterioration of the bearing performance and the seizure and breakage of a bearing device due to the deflection in the horizontal direction of an upper part bearing and a lower part bearing at an abutment part. CONSTITUTION: A stage difference part 23 consisting of the fitting surfaces 23b and 23c which are horizontal for the abutment part between an upper part bearing 22 and a lower part bearing 21 and a fitting surface 23a which is parallel to the axis center 3a of a rotary shaft 3 and crosses at right angle with the fitting surfaces 23b and 23c is formed, and the upper part bearing 22 and the lower part bearing 21 are fitted on the fitting surface 23a of the stage difference part 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plain bearing device suitable for main bearings for marine diesel engines.

[0002]

2. Description of the Related Art One example of a conventional plain bearing device is shown in FIGS. As shown in FIG. 2 (A), this type plain bearing device is provided with a semi-annular upper bearing 022 and a semi-annular lower bearing 021 that are vertically divided into two parts on a horizontal dividing surface. The bearing 021 supports a crankshaft 03 that extends substantially horizontally. The lower bearing 021 is guided by the positioning pin 04 and the slit 041 and is attached to the bearing base 01.
The upper bearing 022 is fitted to the mounting surface 010a of the bearing retainer 010 by being guided by the rotation stop pin 09.

The upper bearing 022 and the lower bearing 021 are abutted against each other through the adjusting liner 05 on both sides thereof, and the adjusting liner 05 is connected to the upper bearing 022 by the pin 06 as shown in FIG. 2 (B). It is positioned and fastened to the upper bearing 022 by dowel pin 07 and bolt 08.

The upper bearing 022 has the head of the dowel pin 07 as the lower bearing.
Lower bearing 021 by fitting in guide hole 071 of 021
Is positioned relative to. Then, by tightening the bearing retainer 010 and the bearing base 01 with the bolt 11, the upper bearing
The 011 and the lower bearing 021 are fixed between the bearing retainer 010 and the bearing base 01.

After that, as shown in FIG. 3, the height from the top surface of the bearing retainer 010 to the upper surface of the crankshaft 03 is measured with a micrometer along the measurement hole 012, and the bearing retainer 010 is measured from the measured value. Crankshaft by subtracting the thickness of
Calculate the clearance C between the upper surface of 03 and the inner surface of the upper bearing 022.
When the calculated gap C exceeds a predetermined tolerance, the thickness of the adjustment liner 05 is changed so that the gap C falls within the tolerance.

[0006]

In the conventional plain bearing device described above, the accuracy of alignment of the lower bearing 021 and the upper bearing 022 in the horizontal direction and the axial center direction of the crankshaft 03 is determined by the dowel pin 07.
It depends on the dimensional accuracy of the head and guide hole 071.

However, since there is usually a diameter difference of about 0.1 mm between the head of the dowel pin 07 and the guide hole 071, it is about 0.1 to 0.15 mm in the horizontal direction as shown in FIG. A deviation δ may occur on the abutting surfaces of the upper bearing 022 and the lower bearing 021.

On the other hand, since the bearing load applied to the crankshaft 03 is constantly fluctuating, the crankshaft 03 moves around within the range of the bearing clearance C while rotating, but at that time, a horizontal shift δ is formed. When the upper bearing 022 and the lower bearing are
There was a risk that 021 would come into metal contact with the crankshaft 03 and cause seizure or damage.

The object of the present invention is to provide an upper bearing 02
The object of the present invention is to provide a plain bearing device having high durability and reliability by preventing the formation of a shift in the abutting portion of the lower bearing 021 and the lower bearing 021 to prevent deterioration of bearing performance and seizure or damage.

[0010]

SUMMARY OF THE INVENTION The present invention has been invented to solve the above problems, and its gist is to provide a semi-annular upper bearing and a semi-annular upper bearing which are vertically divided into two parts. The lower bearing and the lower bearings are butted against each other at their abutting portions, and the upper bearing and the lower bearing support a rotating shaft that extends substantially horizontally, and the bearing retainer is tightened to the bearing stand with bolts to support the bearing retainer. In a plain bearing device in which the upper bearing and the lower bearing are fixed between the upper bearing and the lower bearing, parallel mating surfaces parallel to the abutting portions of the upper bearing and the lower bearing and parallel to the axis of the rotary shaft, Also, there is provided a plain bearing device characterized in that a step portion formed of a fitting surface orthogonal to the mating surface is formed, and the upper bearing and the lower bearing are fitted to each other at the fitting surface of the step portion. .

[0011]

According to the present invention, even if a horizontal force acts on the abutting portion of the upper bearing and the lower bearing due to the rotating shaft moving around in the bearing gap while rotating, this force is applied to the fitting surface of the stepped portion. Since the upper bearing and the lower bearing do not horizontally shift at the abutting portion.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is shown in FIG. 1, where (A) is a longitudinal sectional view and (B) is an enlarged sectional view taken along the line BB of (A). In FIG. 1, 1 is a bearing stand, 3 is a crankshaft, 22 is an upper bearing, 21 is a lower bearing, 10 is a bearing retainer, and 11 is a bolt.

At the abutting portions on both sides of the upper bearing 22 and the lower bearing 21, horizontal mating surfaces 23b and 23c are parallel to the axis 3a of the crankshaft 3, and a mating surface 23 perpendicular to the mating surfaces 23b and 23c.
A step portion 23 formed of a is configured. The mating surface 23c is located on the outer peripheral side and above the mating surface 23b, and the mating surface 23b and the mating surface 23c are continuous via the fitting surface 23a.

An adjusting liner 5 is provided on the mating surface 23c,
This adjustment liner 5 has pins 6 as shown in FIG. 1 (B).
Is positioned on the upper bearing 22 and is fastened to the upper bearing 22 by the dowel pin 7. The upper bearing 22 and the lower bearing 21 are positioned by fitting the head of the dowel pin 7 into the guide hole 71 provided in the lower bearing 21.

The upper bearing 22 is guided by the anti-rotation pin 9 and fitted to the mounting surface 10a of the bearing retainer 10. The lower bearing 21 is guided by the slit 41 formed in the bearing base 1 and the positioning pin 4 fitted therein, and is fitted to the mounting surface 1a of the bearing base 1.

When assembling the plain bearing device, the upper bearing 22 and the lower bearing 21 are assembled in a jig (not shown) in a state where they are fitted to each other at the step portion 23 and integrated, and then the upper bearing 22 and the lower bearing 21 are assembled. The inner peripheral surface 30 is machined into a perfect circle.

After machining the inner peripheral surface 30, the upper bearing 22 and the lower bearing 21 are removed from the jig, the lower bearing 21 is fitted on the mounting surface 1a of the bearing stand 1, and the crankshaft 3 is mounted on the lower bearing 21. Place it. Then, the upper bearing 22 is fitted to the lower bearing 21 by fitting the stepped portion 23.

Thereafter, the bearing retainer 10 is fitted to the upper bearing 22 by using the detent pin 9 as a guide, and the bolt 11 is tightened to fix the bearing retainer 10 to the bearing stand 1. This allows the upper bearing
The lower bearing 22 and the lower bearing 21 are firmly fixed between the mounting surface 1a of the bearing stand 1 and the mounting surface 10a of the bearing retainer 10.

During operation of the engine, the crankshaft 3 moves in the bearing clearance C while rotating due to fluctuations in the bearing load, so that a horizontal force acts on the abutting portion of the upper bearing 22 and the lower bearing 21. Lower bearing 22 and lower bearing
Since 21 is fitted by the fitting surface 23a extending in the vertical direction, the fitting surface 23a supports the force in the horizontal direction. There is no gap.

[0020]

According to the present invention, the upper bearing and the lower bearing each have a mating surface that is horizontal and a mating surface that is parallel to the axis of the rotary shaft and that is orthogonal to the mating surface. Since the step portion is formed and the upper bearing and the lower bearing are fitted at the fitting surface of the step portion, the horizontal direction acting on the abutting portion of the upper bearing and the lower bearing during operation of the engine Since the fitting surface supports the force, it is possible to prevent the horizontal displacement of the upper bearing and the lower bearing at the abutting portion.

Therefore, the upper bearing and the lower bearing are always firmly fitted in the abutting portion and the amount of deformation of the bearing due to the horizontal force is reduced, so that deterioration of the bearing performance, seizure, and damage may occur. Can be prevented.
This greatly improves the durability and reliability of the plain bearing device.

[Brief description of drawings]

FIG. 1 shows a plain bearing device for a large marine diesel engine according to an embodiment of the present invention, (A) is a longitudinal sectional view, and (B) is an enlarged sectional view taken along line BB of (A). .

FIG. 2 shows an example of a conventional plain bearing device, (A) is a longitudinal sectional view, and (B) is an enlarged sectional view taken along the line BB of (A).

FIG. 3 is an enlarged cross-sectional view taken along the line CC of FIG.

FIG. 4 is an explanatory diagram showing a shift in a conventional plain bearing device.

[Explanation of symbols]

 1 Bearing base 1a Mounting surface 3 Crankshaft 5 Adjusting liner 7 Dowel pin 10 Bearing retainer 10a Mounting surface 11 Bolt 21 Lower bearing 22 Upper bearing 23 Stepped portion 23a Mating surface 23b, 23c Mating surface 30 Bearing inner surface

Claims (1)

[Claims] 1. A semi-annular upper bearing and a semi-annular lower bearing, which are vertically divided into two parts, abut on each other at abutting portions on both sides thereof, and the upper bearing and the lower bearing extend substantially horizontally. In a plain bearing device in which the upper bearing and the lower bearing are fixed between the bearing retainer and the bearing stand by supporting the rotating shaft and tightening the bearing retainer to the bearing stand with bolts, the upper bearing and the lower bearing are At the abutting portion of each of them, a step portion formed of a horizontal mating surface and a mating surface parallel to the axis of the rotating shaft and orthogonal to the mating surface is formed, and the upper bearing and the lower bearing are separated from each other by the step. A plain bearing device characterized by being fitted at a fitting surface of a section.