JPH03255222A - Eccentric bearing and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain an eccentric bearing having a high accuracy in thickness and a thin plating layer and excellent in load withstanding property by forming a developed back plate into a circular-arc, and forming it into an eccentric inner circumferential surface, and then by applying plating to it so as to have a thickness less than 0.2mm for obtaining a bearing layer. CONSTITUTION:An eccentric bearing 1 comprises a circular-arc-shaped back plate 2, and a bearing layer 3 in which plating of a thickness less than 0.2mm is applied on the inner circumferential surface that has been eccentrically formed from the outer circumferential surface of the back plate. The thickness of the back plate 2 at the end part is thinner than that at the central part thereof. In this manufacturing process, a back-plate material 12 is cut out from a plate material 11, and it is formed into a circular-arc-shaped formed body 13, and grooves 6 or the like are machined and the inner surface thereof is finished to have a prescribed eccentricity, and then plating of a thickness less than 0.2mm is evenly applied for obtaining the bearing layer 3. Since the machining accuracy in the inner surface of the back plate can be enhanced, and thin plating will be sufficient, and the accuracy in thickness can be increased, a good load with-standing property, and fatigue resistance can be obtained, and also productivity can be enhanced.

Description

[Detailed description of the invention] [Purpose of the invention]

(Field of Industrial Application) The present invention relates to an eccentric bearing used to receive and support a shaft in various internal combustion engines such as automobiles, and a method for manufacturing the same. (Prior Art) Bearings used to receive and support shafts in various internal combustion engines such as automobiles include ball bearings and bell bearings, and the present invention is particularly focused on the latter type of sliding bearings (metal bearings). ). Fig. 4 illustrates the structure of this type of plain bearing, and shows the structure of a half-split metal bearing. This half-split metal bearing 21 has a semi-cylindrical shape. Eggplant back metal material 2
It has a bearing layer 23 on the inner peripheral surface side of the oil groove 2, and has oil #1I24 in the arc direction in the middle part of the radial direction.
4 has an oil hole 25, and has a general structure in which a claw 26 is provided at the end. FIG. 5 is an enlarged view of the AA′ section in FIG. 4 for explanation, and shows a bearing layer 23 on the inner circumferential surface of a back metal material 22 that serves as the base of the half-split metal bearing 21. The outer peripheral surface of the H metal material 22 has an arc shape with a radius D1 centered on the center of curvature 0, and the inner peripheral surface of the back metal material 22 has an arc shape with a radius D4 centered on the center of curvature 0. The wall thickness t3 of the bearing layer 2 is equal to the wall thickness t3 of the end portion.
The inner circumferential surface of the bearing layer 23 has an arcuate shape with a radius D2 centered on the center of curvature 0' which is eccentric from the center of curvature 0 by eccentric processing of the inner circumferential surface of the bearing layer 23.
The inner circumferential surface of No. 3 has a bearing surface 27 at its center, oil reliefs 28 on both sides, and crush reliefs 22 on both ends, and is called an eccentric bearing. It has become something that A bearing is placed on the inner peripheral surface of such a semi-cylindrical back metal material 22!
In manufacturing the half bearing 21 having fj23, as shown in Fig. 6(d) and Fig. M47(a), an aluminum alloy,
A multilayer material 30 is used in which bearing layers 23 made of copper-based alloy, lead-based alloy, tin-based alloy, etc. are laminated by a metallurgical method. When the bearing 21 is made of aluminum, such a multilayer material 30 is composed of a coiled steel strip 32 that becomes the back metal material 22 and a bearing layer 23, as shown in FIG. 6(a). The coil-shaped aluminum bearing plates 33 are pulled out and passed through pressure rolls 34 and 35 to be pressed together, and then passed through an annealing furnace 36 and annealed to produce the multilayer material 30 shown in FIG. 6(d). be done. This is true if the bearing 21 is made of copper. As shown in FIG. 6(b), a bearing M2 housed in the hopper 44 is placed on the upper surface of the coiled steel strip 42 that becomes the back metal material 22.
Copper alloy powder 43 to be used as No. 3 is scattered, and in this state, the sintering furnace 4 is
The multilayer material 3o shown in FIG. 6(d) is manufactured by passing the material through a roller 5, sintering it, and then rolling it with rolling rolls 46, 47. Furthermore, when the bearing 21 is made of a white metal bearing, as shown in FIG. 6(C), the back metal material 22
After the coiled steel strip 52 is pretreated by passing it through a pretreatment B111+54. A white metal base metal molten metal 53 that will become the bearing layer 23 housed in a molten metal container 55 is poured onto the upper surface of this steel strip plate 52,
By finishing with the cutter 56, as shown in FIG. 6(d).
It is manufactured as a multilayer material 30 shown in FIG. In this case, the thickness of these bearing layers 23 in the multilayering process is 0.25 to 0.30, which is the thickness of the bearing layers 23 in the product.
It is normal to set it to nearly twice that of mm. Aluminum type manufactured as above. When manufacturing the half-split metal bearing z1 shown in FIGS. 4 and 5 using the multilayer material 3o of copper-based, white metal-based, etc., for example, as shown in FIG.
! The multilayer material 30 manufactured by the process shown in J is shown in FIG.
) As shown in FIG. 7(b), the bearing material 61 was cut into strips corresponding to the developed shape of the back metal material 22.
As shown in , the bearing material 61 is formed into a semi-cylindrical molded body 62 with the bearing layer 23 side facing inside, and then
As shown in FIG. 7(c), an oil groove 24 is formed in the middle part of the molded body 62 in the width direction, an oil hole 25 is formed in the oil groove 24, and a claw 26 is formed at the end. Part processing, etc., and the 71st! ! As shown in ff(d),
By finishing the inner circumferential surface to form a curved surface with a radius D20 centered on the center of curvature 0' eccentric from the center of curvature 0, the bearing layer 2 is formed as shown in FIGS. 4 and 5.
A half-split metal bearing 21 having a bearing surface 27 at the center portion of the bearing 3, oil reliefs 28 at both side portions, and a crush relief 222 at both end portions was obtained. For example, in the half metal bearing 21 provided with the copper-based bearing layer 23, an electroplating overlay may be further applied as a surface layer. (Problem to be Solved by the Invention) However, in such a conventional half metal bearing 21, the material of the back metal material 22 is, for example, JIS
We use polished strip steel stipulated in G 3141, and depending on the applicable housing diameter, etc., the plate thickness accuracy is often ±0.08 to 0.12 for motorized wheels.
mm. Therefore, there was a problem in that it was difficult to form a half-split metal bearing 21 in which the bearing layer 23 is thinned to 0.2 mm or less, which is suitable for improving load resistance, fatigue resistance, and the like. That is, in the conventional case, this type of half metal bearing 2
When manufacturing and using 1, the back metal material 22
Since the total thickness of the half metal bearing 21 is determined with priority given to the plate thickness accuracy, the lower limit of the thickness of the bearing layer 23 laminated on the backing metal material 22 is determined by The maximum variation, Q, of about 1 mm was simply the limit. Therefore, the thickness of the bearing layer 23 is determined to absorb variations in the plate thickness of the backing metal material 22 and to provide a relief portion C2B at the end of the bearing.
, 29>, and to prevent the back metal material 22 from being exposed when forming the crush relief 2, the thickness is set to about 0.25 to 0.30 mm. The reality was that there were. (Objective of the Invention) The present invention has been made in view of the above-mentioned conventional problems, and the present invention has been made in view of the above-mentioned conventional problems. This was done for the purpose of extending the lifespan,
Focusing on the fact that variation in the thickness of the bearing layer greatly affects the load capacity and fatigue life of metal bearings, we have taken into consideration the thickness of the bearing layer, which has a large effect on the load capacity and fatigue life of metal bearings. The above-mentioned conventional problems can be solved by first processing and finishing the back metal material and then plating the molded back metal material to create a bearing layer consisting of a plating layer with a thickness of 0.2 mm or less. The purpose is to provide an eccentric bearing that can solve the problem.

[Structure of the invention]

(Means for Solving the Problems) 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 has a circular arc shape with a center of curvature eccentric from the center of curvature of the outer circumferential surface, and the bearing layer laminated on the inner circumferential surface of the back metal material is a plated layer with a thickness of 0.2 mm or less. In addition, the method for manufacturing an eccentric bearing having the above configuration according to the present invention is to cut the backing metal material into strips corresponding to the developed shape of the backing metal material, and then cutting the backing metal material into strips corresponding to the developed shape of the backing metal material. It is formed into an arc shape, and then bearing parts such as oil grooves and oil holes are processed on the arc-shaped molded body, and the inner circumferential surface has a center of curvature eccentric from the center of curvature of the outer peripheral surface of the molded body. A back metal material for an eccentric bearing is formed into an arc shape and has a predetermined thickness, and a bearing layer is uniformly formed on the inner peripheral surface of the front metal material to a thickness of 0.2 mm or less by plating to form an eccentric bearing. The structure of the eccentric bearing and its manufacturing method as described above is a means for solving the above-mentioned conventional problems. (Action of the invention) Since the eccentric bearing and the manufacturing method thereof according to the present invention have the above-described configuration,
Because the dimensional accuracy of the back metal material is reliably high,
The influence on the bearing layer due to variations in the dimensional accuracy of the backing metal material is eliminated, and the thickness of the bearing layer can be reduced to 0.2 mm by plating.
Since the following stability can be achieved, an effect is brought about in which the load resistance and fatigue life of the bearing are excellent and AFL<stable. (Embodiment) FIG. 1 is a slope explanatory diagram 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. It has a circular arc shape, and the bearing layer 3 laminated on the inner circumferential surface of the backing metal material 2 is a plating layer with a thickness of 0.2 mm or less. As is clear from FIG. 2, the eccentric bearing 1 has an arc-shaped outer circumferential surface of the back metal material 2 having an arc shape with a radius centered at the center of curvature 0. The inner peripheral surface of the material 2 has a radius D centered on the center of curvature O' which is eccentric from the center of curvature O.
3, and the wall thickness t1 at the center of the backing metal material 2 is different from the wall thickness t2 at the end side, with the wall thickness t2 at the end side being different. The shape is smaller than the wall thickness t1 at the center. A bearing layer 3 is formed on the inner circumferential surface of the backing metal material 2 by a plating layer of uniform thickness, and the inner circumferential surface of the bearing layer 3 is centered at the center of curvature O' which is eccentric from the center of curvature 0. The bearing layer 3 has a circular arc shape with a radius D2, and the center portion of the bearing layer 3 serves as the bearing surface 7.
It has oil reliefs 8 on both sides and crush reliefs 9 on both end sides, and these ensure smooth flow of lubricating oil and absorption of displacement of the housing cap. In this case, the crush relief 9 is more eccentric than the circular arc surface of radius D2 centered on the center of curvature 0', and its depth is about 0.01 to 0.05 mm. When manufacturing such an eccentric bearing 1, as shown in Fig. 583 (a), for example, JIS G
A strip-shaped plate material 11 made of polished band steel enacted in 3141 was cut into strips corresponding to the developed shape of the backing metal material 2 to obtain the backing metal material 12, and then as shown in FIG. 3(b). , forming the back metal material 12 into an arc shape,
An arc-shaped molded body 13 is formed, and then, as shown in FIG. 3(C), an oil groove 4°, an oil hole 5. By processing each part of the metal bearing, such as the pawl 6, and finishing the inner surface of the arc-shaped molded body 13 as shown in FIG. do. In the final step in this case, the wall thickness finishing step,
A broach cutter, a boring cutter, etc. can be used.1For example, when using a boring cutter, a "boring machine for semi-cylindrical bearings" described in Japanese Patent Publication No. 17960/1983 can also be used. . This boring machine for semi-cylindrical bearings has a bearing support that holds a semi-cylindrical bearing with a vertical axis in a given direction, and two cutters installed at separate locations along the rotation axis. a rotatable boring bar, means for rotating the boring bar, mounting the boring bar with an axis of rotation at a small angle relative to the longitudinal axis of the semi-cylindrical bearing, and rotating the boring bar; one of the two wooden cutters extends further from the boring bar than the other; The force cutter is configured to scrape the inner surface of the semi-cylindrical bearing while rotating around different centers with different cutting radii, and by using such a boring cutter, the back metal for eccentric bearings can be cut. The inner surface of material 2 is finished. Through this machining and finishing process of the backing metal material 2, all bearing parts except the bearing layer 3 are manufactured with high precision.
On the other hand, as shown in FIG. 3Ce), a bearing layer 3 is formed on the inner circumferential surface of the back metal material 2 by plating to a uniform thickness, and as shown in FIG. The eccentric bearing 1 has a bearing surface 7, oil reliefs 8 on both sides thereof, and crush reliefs 9 on both end sides. When forming the bearing layer 3 entirely by plating on the inner circumferential surface of the eccentric bearing back metal material 2,
It is necessary to reconsider not only the sliding characteristics of the bearing 1 but also the compatibility with the shaft, the ability to embed foreign matter, wear resistance, and seizure resistance as conditions that the bearing should have. These conditions may be difficult to meet if the bearing layer 3 is made of a single layer, and even in the conventional bearing made by the metallurgical method illustrated in FIG. A method may be adopted in which the back metal material is multi-layered and the surface layer is made of a rough alloy, and such a method can also be adopted in the present invention, and the back metal material is multi-layered. It is possible to have a structure in which the intermediate layer is formed by plating, and the surface layer is further formed by plating thereon. In this case, when forming the intermediate layer by plating, a known (7) Cu-Pb alloy, Cu-3n alloy is used. It is possible to use a Cu-Zn alloy, etc., and the surface layer can be multi-layered by applying overlay plating mainly composed of Pb, for example, as described in JP-A-47-35.
Japanese Patent Application No. 62 discloses various electrodeposited bearing materials made into multiple layers by plating. Further, in the eccentric bearing according to the present invention, the bearing layer 3 is formed of a plating layer with a thickness of 0.2 mm or less, and this plating layer can be extended to a maximum of 0.2 mm.
It can be said that obtaining a thickness of m is thicker than normal plating, so it may take a long time if a normal plating method is adopted. Therefore, if there is such a risk, it is necessary to use an electroplating apparatus such as that disclosed in Japanese Patent Application Laid-Open No. 58-25500, that is, an anode structure including a plating metal source and the anode structure. At least one stirring blade disposed in an adjacent plating cavity, a rotation means for rotating the stirring blade within the plating cavity, and applying a positive potential to the anode structure. An anode conductor, a positioning means for positioning the plating piece with respect to the anode structure so as to form the plating cavity, and a cathode conductor 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 similar configuration. 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, the third v! As shown in J, a plate material 11 made of a band-shaped steel plate or the like is cut to correspond to the developed shape of the back metal material 2 to obtain a material 12 for the back metal, and then this material 12 for the back metal is cut into an arc shape corresponding to the shape of the metal bearing. This molded body 13 is machined to form parts such as oil grooves 4 and oil holes 5 by cutting, and the inner surface is finished to form a predetermined finished surface. Material 2
The bearing layer 3 of uniform thickness is formed only by plating, and the total thickness accuracy is about 0.008 to 0.01 mm, which is less than that even when the mechanical finishing error and plating error are combined. be. Further, the crush relief 9 can be manufactured without exposing the back metal material 2. In a normal case, a bearing layer 3 having a predetermined accuracy can be obtained directly after forming the bearing layer 3 by plating. In this way, in the eccentric metal bearing 1, the thin bearing layer 3 of 0.2 mm or less can be formed, so that the load resistance and fatigue life are improved. To explain this based on Figure 8, Figure 8 shows the relationship between the wall thickness and durability (life time) of white metal bearing materials, and as is clear from Figure 8. It is shown that there is a sudden change in the lifespan when the white metal wall thickness is around 0.2 mm, and other Cu-based and A! Similar results were obtained for l-based bearing materials, and 0.2 m
It was confirmed that there is a critical point at m thickness. However, it is not sufficient that the thickness of the bearing layer 3 is thin; in practice, a thickness of 0.01 mmJJ or more is required in order to fulfill the role of embedding foreign matter. By the way, when trying to manufacture a plated bearing with a thin bearing layer with a thickness of 0.2 mm using a back metal material made of a conventional polished strip steel material with precision plate thickness, the maximum variation in the back metal material Q is 12 mm, resulting in a crash. Relief standard 0.05
If you add mm to O, 17 mm, and if you include other errors, it is impossible to manufacture eccentric bearings. Even if it were possible to manufacture eccentric bearings, the back metal material and bearing layer would be eccentric and there would be no crush relief. This results in a concentric bearing in which each layer of the bearing is made up of concentric circles. However, as the bearing layer becomes thinner, the provision of oil relief and crush relief becomes essential in order to absorb displacement of the housing cap and displacement of the end joints of half bearings, and to prevent seizure. Therefore, in the present invention, first, a backing metal material for an eccentric bearing is formed by internal finishing to produce a backing metal material for an eccentric bearing with a predetermined wall thickness and high dimensional accuracy, and then a bearing layer is formed on the backing metal material for an eccentric bearing. by 0.2
The thickness was set to be less than mm. This makes it possible to obtain a long-life metal bearing with even better load-bearing and fatigue-resistant life.

【Effect of the invention】

The 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 eccentric from the center of curvature of the outer peripheral surface. It has a circular arc shape with the center of curvature, and the bearing layer laminated on the inner circumferential surface of the back metal material is a plating layer with a thickness of 0.2 mm or less. The method for manufacturing the bearing is to cut the backing metal material according to the developed shape to obtain a backing metal material, and then forming the backing metal material into an arc shape. Next, the bearing portion of the arc-shaped molded body is processed, and the molded body is molded into an arc shape having an inner peripheral surface with a center of curvature eccentric from the center of curvature of the outer peripheral surface of the molded body to form an eccentric I of a predetermined thickness. This is a backing metal material for a bearing, and a bearing layer is uniformly formed on the backing metal material with a thickness of 0.2 mm or less by plating to form an eccentric bearing.
Unlike in the past, variations in the thickness accuracy of steel plates and other plate materials used as backing metal materials do not appear as variations in the thickness of the bearing layer, and the accuracy of the thickness of the backing metal material and the thickness of the bearing layer is significantly improved. It has become possible to obtain eccentric bearings with a high bearing layer and a thin bearing layer thickness, which has the remarkable effect of providing high-quality bearings with excellent load carrying capacity and long fatigue life. It will be done. Further, since the present invention can be carried out without requiring conventional large-scale metallurgical equipment and metallurgical processes using the same, it is possible to significantly improve productivity.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a slope of an eccentric bearing according to an embodiment of the present invention, FIG. 2 is a partially enlarged view illustrating the structure of an eccentric bearing according to an embodiment of the present invention, and FIGS. ) are explanatory diagrams sequentially illustrating the manufacturing process of the eccentric bearing according to the present invention, FIG. 4 is a slope explanatory diagram illustrating the structure of a conventional eccentric bearing, and FIG. 5 is 1! An enlarged view illustrating the structure of the A-A' island part in Figure s4, and Figures 6 (a) to (d) are explanations showing the process of forming a multilayer bearing layer on a conventional copper strip to obtain a multilayer material. 7(a) to 7(d) are explanatory diagrams sequentially illustrating the manufacturing process of a conventional half-split bearing, and FIG. 8 is a graph illustrating the relationship between the thickness of white metal and durability. DESCRIPTION OF SYMBOLS 1... Eccentric bearing, 2... Back metal material, 3... Bearing layer, 27... Bearing surface, 28... Oil relief, 22... Crash relief.

Claims (2)

[Claims] (1) It 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 has a circular arc shape with a center of curvature eccentric from the center of curvature of the outer peripheral surface. An eccentric bearing characterized in that the bearing layer laminated on the inner circumferential surface of the back metal material is a plating layer having a thickness of 0.2 mm or less. (2) After cutting the backing metal material to correspond to the developed shape of the backing metal material, forming the backing metal material into an arc shape, and then processing the bearing part on the arc-shaped molded body, A backing metal material for an eccentric bearing having a predetermined thickness is formed by forming the molded body into an arc shape having an inner peripheral surface whose center of curvature is eccentric from the center of curvature of the outer peripheral surface of the molded body, and a bearing layer is plated on the inner peripheral surface of the backing metal material. 2. The method of manufacturing an eccentric bearing according to claim 1, wherein the eccentric bearing is formed by uniformly forming the eccentric bearing with a thickness of 0.2 mm or less.