JPH0765617B2 - Eccentric bearing and manufacturing method thereof - Google Patents

Description

Detailed Description of the Invention [Object of the Invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eccentric bearing used for receiving and supporting a shaft in various internal combustion engines such as automobiles and a method for manufacturing the eccentric bearing. (Prior Art) In various internal combustion engines such as automobiles, there are ball bearings and slide bearings as bearings used for receiving and supporting a shaft, and the present invention particularly relates to the latter slide bearing (metal bearing). ) Is related to. FIG. 4 exemplifies the structure of this type of slide bearing and illustrates the structure of a half metal bearing. This half metal bearing 21 has a bearing layer 23 on the inner peripheral surface side of a backing metal member 22 having a semi-cylindrical shape, and has an oil groove 24 in an arc direction in an intermediate portion in the width direction, and an oil Oil hole in the groove 24
It has a general structure having 25 and claws 26 at the ends. FIG. 5 is an enlarged view of the portion AA ′ in FIG. 4 for the purpose of explanation.
Has a bearing layer 23 on the inner peripheral surface thereof, and the outer peripheral surface of the backing metal material 22 has an arc shape with a radius D ₁ centered on the center of curvature O and
The inner peripheral surface of the 22 have an arc shape having a radius D _4, which also centered on the curvature center O, has become a wall thickness t ₃ of the central thickness t ₃ and the end portion shall equal the bearing layer The inner peripheral surface of 23 has an arcuate shape with a radius D ₂ centered on a center of curvature O ′ that is eccentric from the center of curvature O by eccentric processing of the inner peripheral surface of the bearing layer 23. The inner peripheral surface of the has a bearing surface 27 at its center portion, has oil reliefs 28 on both sides of the bearing surface 27, and has crush reliefs 29 on both end sides, and is called a so-called eccentric bearing. It has become a thing. The bearing layer 23 is formed on the inner peripheral surface side of the semi-cylindrical backing material 22.
As shown in FIGS. 6 (d) and 7 (a), when manufacturing the half bearing 21 having an aluminum-based alloy, a copper-based alloy, a lead-based alloy on one side of the backing metal material 22 made of a steel plate. A multi-layer material 30 in which bearing layers 23 made of an alloy, a tin-based alloy or the like are laminated by a metallurgical method is used. When the bearing 21 is made of aluminum, as shown in FIG.
The coil-shaped strip steel plate 32 and the coil-shaped aluminum bearing plate 33 to be the bearing layer 23 are drawn out and passed through the press-contact rolls 34 and 35 for pressure contact, and are passed through the annealing furnace 36 for annealing. Multi-layer material shown in FIG. 6 (d)
Manufactured as 30. Further, when the bearing 21 is made of copper, as shown in FIG.
The copper alloy powder 43 to be the bearing layer 23 accommodated in the hopper 44 is dispersed on the upper surface of the, and in this state, the copper alloy powder 43 is passed through the sintering furnace 45 to be sintered and then rolled by the rolling rolls 46 and 47. 6
It is manufactured as the multilayer material 30 shown in FIG. Further, when the bearing 21 is made of a white metal bearing, as shown in FIG. 6 (c), the coil-shaped strip steel plate 52 serving as the backing metal material 22 is passed through the pretreatment facility 54 to perform the pretreatment. After that, the white metal alloy molten metal 53, which will be the bearing layer 23 accommodated in the molten metal container 55, is poured onto the upper surface of the strip steel plate 52, and finished with a cutter 56 to finish the compound shown in FIG. Manufactured as layer material 30. In this case, the thickness of these bearing layers 23 in the multilayering process is
Normally, the thickness is set to nearly double the thickness of the bearing layer 23 at the time of manufacture, which is 0.25 to 0.30 mm. Using the aluminum-based, copper-based, white metal-based multi-layer material 30 manufactured as described above, FIGS.
When manufacturing the half-divided metal bearing 21 as shown in the figure, for example, as shown in FIG. 7, the multilayer material 30 manufactured by the process shown in FIG. 6 is processed as shown in FIG. 7 (a). After cutting into strip shapes corresponding to the developed shape of the backing metal material 22 to obtain a bearing material 61, as shown in FIG. 7 (b), a half cylinder is formed with the bearing layer 23 side of the bearing material 61 inside. Molded into a shaped molded body 62, and then, as shown in FIG. 7C, an oil groove 24 is formed in the widthwise intermediate portion of the molded body 62 and an oil hole 25 is formed in the oil groove 24. Then, a part is formed to form the claw 26 at the end, and further, as shown in FIG. 7D, a curved surface having a radius D ₂ centered on a curvature center O ′ decentered from the curvature center O is formed. As shown in FIGS. 4 and 5, the bearing layer is finished by finishing the inner peripheral surface so that
The half-divided metal bearing 21 has the bearing surface 27 at the central portion of 23, the oil reliefs 28 at both side portions, and the crush reliefs 29 at both end portions. Then, for example, in the half-divided metal bearing 21 provided with the copper-based bearing layer 23, an overlay by electroplating may be further applied as a surface layer. (Problems to be Solved by the Invention) However, in such a conventional half-split metal bearing 21, the material of the back metal member 22 is, for example, JIS G 314.
It uses the steel strip that was established in 1 above, and its plate thickness accuracy is mostly ± 0.08 to 0.12 mm in the case of automobiles, depending on the housing diameter to which it is applied. Therefore, there is a problem that it is difficult to make the bearing layer 23 suitable for improving load resistance and fatigue resistance into a half-divided metal bearing 21 having a thickness of 0.2 mm or less. That is, in the conventional case, this type of half metal bearing 21
When manufacturing and using, since the total thickness dimension of the half metal bearing 21 is determined by giving priority to the plate thickness accuracy of the backing metal material 22, the bearing layer 23 laminated on the backing metal material 22 is The lower limit of the thickness is the maximum variation in the thickness of the backing material 22.
A limit of 1 mm was a simple limit. Therefore, the thickness of the bearing layer 23 absorbs the variation in the plate thickness dimension of the backing metal 22 and the relief portion (28, 29) provided at the bearing end portion.
In consideration of the shape, etc., and in order to prevent the backing metal material 22 from being exposed when forming the crush relief 29, the actual thickness was set to about 0.25 to 0.30 mm. . (Object of the Invention) The present invention has been made in view of the above-mentioned conventional problems, and the metal bearing of this type has a long output under high speed and high load due to the recent increase in output of automobiles. It was made for the purpose of achieving a longer life,
Focusing on the fact that variations in the thickness of the bearing layer have a large effect on the load bearing capacity and fatigue life of the metal bearing, and considering the thickness of the bearing layer that greatly affects the load bearing capacity and fatigue life of the metal bearing, By subjecting the back metal material to a finishing process first, and then plating the back metal material that has been subjected to this forming finish to form a bearing layer made of a plating layer having a thickness of 0.2 mm or less, the above-mentioned conventional problems are solved. The object is to provide an eccentric bearing that can be solved.

[Constitution of the invention]

(Means for Solving the Problem) An eccentric bearing according to the present invention has a laminated structure of an arc-shaped back metal material and a bearing layer laminated on the inner peripheral surface of the back metal material, and the inner peripheral surface of the back metal material. Is a circular arc shape having a center of curvature decentered from the center of curvature of the outer peripheral surface, and the bearing layer laminated on the inner peripheral surface of the back metal material is a plating layer having a thickness of 0.2 mm or less. Further, the method for manufacturing an eccentric bearing having the above-mentioned configuration according to the present invention is such that the back metal material is cut into strips or the like corresponding to the developed shape of the back metal material to form the back metal material, and then the back metal material is formed into an arc shape. And then perform bearing part processing such as oil grooves and oil holes on the arc-shaped molded body, and have an arc-shaped body having an inner peripheral surface with a center of curvature decentered from the center of curvature of the outer peripheral surface of the molded body. Molded into a specified thickness The eccentric bearing is characterized in that it is a backing metal material for an eccentric bearing, and a bearing layer is uniformly formed on the inner peripheral surface of the backing metal material by plating to a thickness of 0.2 mm or less to form an eccentric bearing. The structure of the bearing and the manufacturing method thereof is used as means for solving the above-mentioned conventional problems. (Operation of the Invention) Since the eccentric bearing and the method for manufacturing the same according to the present invention have the above-described configuration,
Since the dimensional accuracy of the back metal is definitely high,
The bearing layer is not affected by variations in the dimensional accuracy of the backing metal, and the bearing layer can be plated to a stable thickness of 0.2 mm or less. This brings about the effect that the life is remarkably stable and excellent. (Embodiment) FIG. 1 is a perspective view showing an eccentric bearing according to an embodiment of the present invention.
Has a laminated structure of a back metal material 2 having an arc shape and a bearing layer 3 laminated on the inner peripheral surface of the back metal material 2, and the inner peripheral surface of the back metal material 2 has a center of curvature eccentric from the center of curvature of the outer peripheral surface. And the bearing layer 3 laminated on the inner peripheral surface of the back metal member 2 is a plating layer having a thickness of 0.2 mm or less. In the eccentric bearing 1 shown in FIG. 1, as is apparent from the view shown in FIG. 2, the outer peripheral surface of the back metal member 2 having an arc shape has an arc shape with a radius D ₁ centered on the center of curvature O. In addition, the inner peripheral surface of the backing metal member 2 has an arc shape with a radius D ₃ centered on a center of curvature O ′ that is eccentric from the center of curvature O. the thickness t ₁ is the thickness t ₂ at the end portion side has become different ones, towards the thickness t ₂ at the end side forms a shape smaller than the thickness t ₁ at the central portion. A bearing layer 3 is formed on the inner peripheral surface of the back metal member 2 by a plating layer having a uniform thickness, and the inner peripheral surface of the bearing layer 3 is centered on a center of curvature O ′ decentered from the center of curvature O. has become one an arc shape having a radius D ₂ of the central portion of the bearing layer 3 has an oil relief 8 on both sides of the bearing surface 7 together has a bearing surface 7, further crush relief at both ends 9 With these features, the smooth flow of the lubricating oil and the absorption of the displacement of the housing cap can be satisfactorily absorbed. In this case, the crush relief 9 is more eccentric than the arcuate surface having the radius D ₂ centered on the center of curvature O ′, and its depth is about 0.01 to 0.05 mm. In manufacturing such an eccentric bearing 1, as shown in FIG. 3 (a), for example, JIS G 3141
The strip-shaped plate material 11 made of polished steel strip, which was established in 1., is cut into strip-shaped materials 12 corresponding to the developed shape of the backing metal material 2, and as shown in FIG. 3 (b), The material 12 for the back metal is formed into an arc shape, and an arc-shaped formed body 13 is formed.
Then, as shown in FIG. 3 (c), the arc-shaped molded body 13 is machined for each part of the metal bearing such as the oil groove 4, the oil hole 5, the claw 6 and the like. As shown in FIG. 3D, the inner surface of the arc-shaped molded body 13 is finished to obtain the back metal member 2 for eccentric bearing having a predetermined wall thickness. In the final step in this case, the thick finish step,
A broach cutter, a boring cutter, or the like can be used. For example, when the boring cutter is used, the "boring machine for semi-cylindrical bearing" described in JP-B-40-17960 can also be used. This boring machine for semi-cylindrical bearings has a bearing support for holding a semi-cylindrical bearing having a vertical axis in a given direction, and two cutters provided at positions spaced apart along the rotation axis. A rotatable boring bar, a means for rotating the boring bar, the boring bar is attached with a rotary shaft having a small angle with respect to the longitudinal axis of the semi-cylindrical bearing, and the boring bar is rotated. And a means for moving the semi-cylindrical bearing in a direction parallel to the longitudinal axis thereof, one of the two cutters extending further from the boring bar than the other cutter, The cutter has a structure in which the inner surface of the semi-cylindrical bearing is scraped off while rotating the surroundings of different centers with different cutting radii. By using such a boring cutter, the backing metal material 2 for eccentric bearing is Inner surface finish Is performed. By this processing and finishing step of the backing metal material 2, all the bearing parts except the bearing layer 3 are accurately manufactured, and subsequently, with respect to the backing metal material 2 for eccentric bearing, as shown in FIG. , The bearing layer 3 is formed on the inner peripheral surface of the backing metal member 2 by plating to have a uniform thickness.
As shown in the figure, the eccentric bearing 1 has a bearing surface 7 in the central portion of the bearing layer 3, oil reliefs 8 on both sides thereof, and crush reliefs 9 on both end sides. When the bearing layer 3 is entirely formed by plating on the inner peripheral surface of the eccentric bearing backing material 2, not only the sliding characteristics of the bearing 1 but also the compatibility with the shaft,
It is necessary to consider that foreign matter embeddability, wear resistance, and seizure resistance are the conditions that a bearing must have. These conditions may be difficult to meet if the bearing layer 3 is a single layer, and even in the conventional metallurgical method of bearings illustrated in FIG. 6, an intermediate layer alloy having wear resistance and seizure resistance can be used. A method of forming a multilayer on the back metal material and further using a soft alloy as the surface layer may be adopted, and such a method can also be adopted in the present invention, and an intermediate layer to be a multilayer on the back metal material. Can be formed by plating, and a surface layer can be further formed thereon by plating. In this case, when forming the intermediate layer by plating, it is possible to use a known Cu-Pb alloy, Cu-Sn alloy, Cu-Zn alloy, or the like, and the surface layer is, for example, overlay plating mainly containing Pb. It is possible to make the plating layer multi-layered, and Japanese Patent Application Laid-Open No. 473562 discloses various electrodeposition bearing materials which are made multi-layered by plating. Further, in the eccentric bearing according to the present invention, the bearing layer 3 is formed of a plating layer having a thickness of 0.2 mm or less, and it is normal plating to obtain this plating layer with a maximum thickness of 0.2 mm. It can be said that the thickness is thicker than that of No. 1, so that it may take a long time when the normal plating method is adopted. Therefore, when there is such a possibility, for example, an electroplating apparatus as disclosed in JP-A-58-25500, that is, an anode structure including a plating metal source,
At least one stirring blade provided in the plating cavity provided adjacent to the anode structure, rotating means for rotating the stirring blade in the plating cavity, and a positive member for the anode structure. An anode conductor for applying a potential of the plate, positioning means for positioning a plating piece with respect to the anode structure so as to form the plating cavity, and a cathode for applying a negative potential to the plating piece to be plated. It is also possible to use a high current density high speed electroplating apparatus having a configuration including a conductor. Further, it is known as a plating technique, for example, JP-A-55-81.
It is also possible to form an Al-based or Cu-based bearing layer by the sputtering technique described in Japanese Patent Publication No. 147 and Japanese Patent Laid-Open Publication No. 55-65121. In the present invention, when manufacturing the eccentric metal bearing 1 in which the bearing layer 3 is thinned to 0.2 mm or less,
As shown in FIG. 3, a plate material 11 made of a strip steel plate or the like is cut into a back metal material 12 corresponding to the developed shape of the back metal material 2, and the back metal material 12 corresponds to a metal bearing shape. A back metal for an eccentric bearing which is formed into an arc shape and which is then machined to form parts such as oil grooves 4 and oil holes 5 and to finish the inner surface to form a predetermined finished surface. The material 2 is used to form the bearing layer 3 having a uniform thickness only by plating, and the total wall thickness accuracy is about 0.008 to 0.01 mm, which is less than the sum of mechanical finishing error and plating error. . Moreover, the crush relief 9 can be manufactured without exposing the backing material 2. In the usual case, after the bearing layer 3 is formed by plating, the bearing layer 3 having a predetermined accuracy can be obtained as it is. Thus, in the eccentric metal bearing 1, since the thin bearing layer 3 having a thickness of 0.2 mm or less can be formed, the load bearing property and the fatigue life are improved. This will be explained with reference to FIG. 8. This FIG. 8 shows the relationship between the wall thickness of the white metal bearing material and the durability (life time). Shows that the life of the white metal changes abruptly when the wall thickness is around 0.2 mm, and similar results were obtained with other Cu-based and Al-based bearing materials. It was confirmed that there was a critical point. However, it is not necessary that the thickness of the bearing layer 3 is thin, and a thickness of 0.01 mm or more is required for practical use in order to play a role of foreign matter burying property. By the way, if you try to manufacture a plated bearing with a thin bearing layer with a thickness of 0.2 mm using a conventional backing material made of strip steel, it is the maximum variation in the backing material.
If you add 0.12 mm and 0.05 mm of crush relief standard
It becomes 0.17 mm, and it is impossible to manufacture an eccentric bearing if other errors are included.Even if it can be manufactured, the back metal and bearing layer are eccentric and there is no crash relief, and each bearing layer is concentric. It becomes a concentric bearing. However, the provision of the oil relief and the crush relief is indispensable for preventing the seizure as the bearing layer becomes thinner, particularly when the displacement of the housing cap or the displacement of the end fitting portion of the half bearing is absorbed. Therefore, in the present invention, first of all, the back metal material is first formed by inner surface finishing to produce a highly accurate eccentric bearing back metal material with a predetermined wall thickness, and then the bearing layer is plated on the eccentric bearing back metal material by 0.2 mm
It was formed to have the following thickness. This has made it possible to obtain long-life metal bearings with even better load bearing and fatigue life.

【The invention's effect】

The eccentric bearing according to the present invention has a laminated structure of a back metal material having an arc shape and a bearing layer laminated on the inner peripheral surface of the back metal material, and the inner peripheral surface of the back metal material is eccentric from the center of curvature of the outer peripheral surface. In addition to forming an arc shape with a center of curvature, the bearing layer laminated on the inner peripheral surface of the back metal material is composed of a plating layer having a thickness of 0.2 mm or less. The manufacturing method is to cut the material corresponding to the developed shape of the backing metal into a material for the backing metal,
An arc shape in which the material for the back metal is formed into an arc shape, and then the bearing part is machined to the arc shape formed body, and an inner peripheral surface having a center of curvature decentered from the center of curvature of the outer peripheral surface of the formed body. The back metal for eccentric bearings is molded into a predetermined thickness and the bearing metal is plated to a thickness of 0.2 mm or less to form an eccentric bearing. Variations in plate thickness accuracy of plate materials such as steel sheets do not appear as variations in the thickness of the bearing layer, and the accuracy of the thickness of the backing metal and the thickness of the bearing layer are extremely high. It is possible to obtain an eccentric bearing having a small thickness, and therefore, it is possible to provide a bearing having excellent load bearing capacity and long fatigue life and good quality. It is brought about. Further, since the present invention can be carried out without the need for a large-scale metallurgical facility and a metallurgical process using the same as in the conventional case, it is possible to significantly improve productivity.

[Brief description of drawings]

FIG. 1 is an explanatory view of a slope of an eccentric bearing according to an embodiment of the present invention, FIG. 2 is a partially enlarged view for explaining the structure of an eccentric bearing according to an embodiment of the present invention, and FIG. 3 is an eccentric bearing according to the present invention. FIG. 4 is an explanatory view sequentially illustrating the manufacturing process of the bearing, FIG. 4 is an explanatory view of a sloping surface illustrating the structure of a conventional eccentric bearing, and FIG. 5 is an enlarged view illustrating the structure in the section AA ′ of FIG. 6 (a) to 6 (d) are explanatory views showing a process of forming a bearing layer on a conventional steel strip to obtain a multi-layered material, and FIG. 7 sequentially illustrates a process of manufacturing a conventional half bearing. Explanatory drawing and FIG. 8 are graphs illustrating the relationship between the wall thickness of white metal and durability. 1 ... Eccentric bearing, 2 ... Back metal, 3 ... Bearing layer,
27… Bearing surface, 28… Oil relief, 29… Crash relief.

Claims (2)

[Claims] 1. A laminated structure of an arc-shaped backing metal and a bearing layer laminated on the inner peripheral surface of the backing metal, wherein the inner peripheral surface of the backing metal has a center of curvature eccentric from the center of curvature of the outer peripheral surface. An eccentric bearing having an arc shape and a bearing layer laminated on the inner peripheral surface of the backing metal material being a plating layer having a thickness of 0.2 mm or less. 2. A material for a back metal is cut in accordance with a developed shape of the back metal, a material for the back metal is formed into an arc shape, and then a bearing portion is processed on the arc-shaped formed body. Together with the back metal material for an eccentric bearing having a predetermined wall thickness by molding into an arc shape having an inner peripheral surface having a center of curvature eccentric from the center of curvature of the outer peripheral surface of the molded body, and a bearing layer on the inner peripheral surface of the back metal material. The method for manufacturing an eccentric bearing according to claim 1, wherein the eccentric bearing is formed by plating to a thickness of 0.2 mm or less to form a uniform eccentric bearing.