KR19990024841U - Journal sliding bearing - Google Patents

Abstract

The present invention discloses a journal sliding bearing. Conventionally, as the diameter of the bearing seat is reduced by the reaction force applied to the center of the bearing housing, the journal sliding bearing is deformed under load, and thus, the indentation degree of the journal sliding bearing is reduced, and the pressure distribution of the oil film is uneven. As a result, boundary friction and rotational shake were generated, which lowered reliability.

According to the present invention, a journal sliding bearing is press-fitted to a bearing seat of a bearing housing, and a plurality of grooves are formed on the outer surface of the journal sliding bearing at equal intervals along the axial direction so that the load caused by the reaction force of the bearing housing is reduced. Therefore, grooves are formed on the outer surface of the journal sliding bearing to improve the degree of indentation and to uniform the pressure distribution of the oil film, thereby improving the rotational characteristics of the shaft, thereby improving product reliability.

Description

Journal sliding bearing

The present invention relates to a journal sliding bearing, and more particularly, to a journal sliding bearing to adjust the degree of indentation due to reaction force.

The bearing is a mechanical element that supports the journal of the axis of rotational movement and the axis of reciprocating motion to maintain its movement smoothly, and receives a load acting on the axis. The types of bearings can be classified into sliding bearings and rolling bearings according to the contact type between the shaft and the bearings, and are classified into journal bearings (or radial bearings) and thrust bearings according to the load direction of the shafts.

Sliding bearings are bearings of sliding friction that have a relatively sliding movement between a shaft and a bearing metal with a thin oil film or pressure gas interposed therebetween. Rolling bearings are bearings of rolling friction caused by a ball or roller rotating body. to be. Therefore, the frictional loss is that the sliding bearing is larger than the rolling bearing. Therefore, in the sliding bearing, an appropriate clearance is provided between the bearing metal and the shaft, and lubricating oil is supplied to the clearance to support the shaft by fluid friction due to the formation of an oil film.

Meanwhile, journal sliding bearings are classified according to the contact type and load direction described above, and the journal sliding bearings are a head drum assembly of a tape recorder such as a video cassette recorder (VCR) or a camcorder (camcorder). The upper drum is rotated at high speed and with high accuracy. In the head drum assembly, the journal sliding bearing is called a metal bearing or an oilless bearing.

As an example of such a conventional journal sliding bearing, as shown in FIGS. 1A and 1B, a shaft hole 11 is formed in the center of the journal sliding bearing 10, and the journal sliding bearing 10 is a bearing housing. The bearing seat 16 of 15 is press-fitted and mounted. In the shaft hole 11 of the journal sliding bearing 10, the journal 21 of the shaft 10 is mounted so that a suitable gap is formed between the inner surface of the shaft hole 11 and the outer surface of the journal 21. (G) is maintained. The lubricating oil O is interposed in the gap G between the shaft hole 11 and the journal 21.

Therefore, an oil film is formed by the lubricating oil O in the clearance gap G between the inner surface of the shaft hole 11 and the outer surface of the journal 21, and the shaft hole 11 and the journal ( The rotation of the shaft 20 is supported without direct contact of 21, and the friction at this time is determined by the viscosity of the lubricant O.

However, in order to press the conventional journal sliding bearing 10 as described above into the bearing seat 16 of the bearing housing 15, the sizing hole 11 of the journal sliding bearing 10 is not illustrated. The journal sliding bearing 10 is pressed in the state of being fitted to the outer circumferential surface of the bar to press-fit the bearing seat 16.

In detail, when the journal sliding bearing 10 is press-fitted into the bearing seat 16 of the bearing housing 15, a pressing force is applied in the radial direction of the bearing housing 15 to provide the bearing seat 16. The diameter is expanded. Then, after the journal sliding bearing 10 is fitted to the bearing seat 16 of the bearing housing 15, a reaction force is applied to the center of the bearing housing 15 to reduce the diameter of the bearing seat 16 and thus the journal The sliding bearing 10 is pressed.

However, as the diameter of the bearing seat 16 is reduced by the reaction force applied to the center of the bearing housing 15, the journal sliding bearing 10 is subjected to a load, thereby press-fitting the journal sliding bearing 10. There was a problem that the degree is lowered and adversely affects the squareness and concentricity.

In addition, when the shaft hole 11 of the journal sliding bearing 10 is deformed by a load and cannot maintain the roundness, the pressure distribution of the oil film becomes uneven and the inner surface of the shaft hole 11 and the shaft 20 The boundary 21 of the journal 21 is in contact with each other, and the boundary friction occurs. As a result of the boundary friction, not only the local overheating and burnout occur, but also the rotational shaking of the shaft 20 causes the rotational characteristics to significantly decrease. There was a problem that the reliability is lowered. In particular, this rotational shake of the shaft 20 poses a serious problem in head drum assemblies requiring high speed and high precision rotation.

The present invention has been made to solve the conventional problems as described above, the object of the present invention is to provide a journal sliding bearing to adjust the degree of indentation by the reaction force.

1a and 1b is a cross-sectional view and a plan view showing a conventional journal sliding bearing,

2 is a perspective view showing a journal sliding bearing according to the present invention,

3a and 3b is a cross-sectional view and a plan view showing a journal sliding bearing according to the present invention.

♣ Explanation of symbols for the main parts of the drawing ♣

30: journal sliding bearing 31: shaft bore

32: groove 35: bearing housing

36: bearing seat 40: shaft

41: Journal G: Niche

O: lubricant

A feature of the present invention for achieving the above object is a lubricating oil for forming an oil film in the gap formed between the inner surface of the shaft hole and the outer surface of the journal, the bearing to rotate to support the shaft by the pressure of the oil film In a journal sliding bearing press-fitted into a bearing seat of a housing, there is a journal sliding bearing in which a plurality of grooves are formed on the outer surface at equal intervals along the axial direction so as to reduce the load caused by the reaction force of the bearing housing.

Hereinafter, one preferred embodiment of a journal sliding bearing according to the present invention will be described in detail with reference to the accompanying drawings.

2 to 3a and 3b is a view showing for explaining the journal sliding bearing according to the present invention.

2 and 3A, the shaft hole 32 is formed in the center of the journal sliding bearing 30, and a plurality of grooves 33 are formed on the inner surface of the journal sliding bearing 30. As shown in FIG. They are formed along the axial direction to maintain equal spacing. The number of the grooves 33 is preferably formed of three or more odd numbers, more preferably, the number of the grooves 33 is formed of five. In this case, when the number of the grooves 33 is five, the grooves 33 are formed to have an equal interval of 72 degrees. In addition, although the grooves 33 are shown to be formed as a triangular groove, the grooves 33 can be appropriately changed into a semicircle and other shapes.

Meanwhile, the journal sliding bearing 30 is press-fitted into the bearing seat 36 of the bearing housing 35, and the journal 41 of the shaft 40 is inserted into the shaft hole 31 of the journal sliding bearing 30. ) Is fitted and positioned, and a suitable gap G is maintained between the inner surface of the shaft hole 31 and the outer surface of the journal 41. The lubricating oil O is interposed in the gap G between the shaft hole 31 and the journal 41.

Therefore, an oil film is formed by the lubricating oil O in the clearance gap G between the inner surface of the shaft hole 31 and the outer surface of the journal 41, and the shaft hole 31 and the journal ( Rotation of shaft 40 is supported without direct contact 41. The friction at this time is determined by the viscosity of the lubricant O, and this lubrication state is called fluid lubrication. In the fluid lubrication state, the inner surface of the shaft hole 31 and the outer surface of the journal 41 are ideally lubricated to prevent friction and wear, and the friction coefficient is minimized.

As shown in FIGS. 3A and 3B, in order to press-fit the journal sliding bearing 30 into the bearing seat 36 of the bearing housing 35, the shaft hole 31 of the journal sliding bearing 30 is opened. The journal sliding bearing 30 is pressed by a press or the like in a state in which it is fitted to the outer circumferential surface of the sizing bar (not shown) to press-fit the bearing seat 36. That is, a sizing bar is used to press-fit the bearing seat 36 and the journal sliding beary 30 to each other, and this series of processes is called so-called sizing.

On the other hand, when looking specifically at the sizing state of the journal sliding bearing 30, when the journal sliding bearing 30 is pressed into the bearing seat 36 of the bearing housing 35, the radial direction of the bearing housing 35 The pressing force is given so that the diameter of the bearing seat 36 is expanded.

In addition, after the journal sliding bearing 30 is fitted to the bearing seat 36 of the bearing housing 35, a reaction force against a pressing force is applied to the center of the bearing housing 35 so that the diameter of the bearing seat 36 is increased. As it is reduced, the journal sliding bearing 30 is press-fitted.

Then, the diameter of the bearing seat 36 is reduced by the reaction force applied to the center of the bearing housing 35, and the journal sliding bearing 30 is subjected to a load. In this case, the groove of the journal sliding bearing 30 is provided. At 32 the reaction forces are reduced. That is, the grooves 32 absorb the load given toward the center of the journal sliding bearing 30 to minimize the amount of deformation of the journal slide bearing 30 by the load.

Since the load is reduced by the grooves 32 of the journal sliding bearing 30 as described above, the degree of indentation is improved to improve the squareness and concentricity, and the roundness of the shaft hole 31 is precisely maintained.

Therefore, while the pressure distribution of the oil film formed between the inner surface of the shaft hole 31 and the outer surface of the journal 41 becomes uniform, the rotation of the shaft 40 is smoothly maintained. For example, by maintaining the pressure distribution of the oil film uniformly, boundary friction generated when the inner surface of the shaft hole 31 and the journal 41 of the shaft 40 come into contact with each other is effectively prevented.

In addition, the rotational shaking of the shaft 40 is prevented, thereby improving the reliability of the product, such as to significantly improve the rotational characteristics. In particular, when the rotational shaking of the shaft 40 is prevented by the grooves 32 of the journal sliding bearing 30, it can be easily employed in the head drum assembly requiring high speed and high precision rotation. .

On the other hand, the above-described embodiment is merely to describe one preferred embodiment of the present invention, the scope of application of the present invention is not limited to such, and can be changed appropriately within the scope of the same idea. For example, the shape and structure of each component specifically shown in the embodiment of the present invention can be modified.

As described above, according to the journal sliding bearing according to the present invention, grooves are formed on the outer surface of the journal sliding bearing to improve the press-fitting degree and to uniformly distribute the pressure distribution of the oil film, thereby significantly improving the rotational characteristics of the product. The reliability is to be improved.

Claims (1)

In the journal sliding bearing which is interposed between the inner surface of the shaft hole and the outer surface of the journal, a lubricating oil forming an oil film is pressed into the bearing seat of the bearing housing so as to support and rotate the shaft by the pressure of the oil film. , Journal of the sliding bearing, characterized in that a plurality of grooves (32) formed on the outer surface at equal intervals along the axial direction so that the load caused by the reaction force of the bearing housing (35) is reduced.