JP2005308021A - Cylindrical bearing member and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylindrical bearing member capable of holding lubricating oil filled in an oil storing blind groove for a long time to sufficiently show the lubricating function thereof, and to provide a cylindrical bearing member manufacturing method capable of efficiently mass-producing the oil storing blind groove inside a cylindrical member at low cost. <P>SOLUTION: This cylindrical bearing member 100 is manufactured by forming a steel strip 110, which is formed with multiple oil storing blind grooves 121 by pressing or roll-forming, into a tubular member, in which the oil storing blind grooves 121 are arranged inside and a bus-like joint is eliminated, by a pipe-in-coil method, and cutting it at the predetermined length. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cylindrical bearing member that is preferably used as a bushing that is rotatably inserted into a connecting pin of a chain, and in particular, an oil reservoir blind groove that serves as an oil reservoir for lubricating oil. The present invention relates to a cylindrical bearing member formed on the inside.

2. Description of the Related Art Conventionally, cylindrical bearing members are used as sliding bearings such as a bearing body of a rotating shaft and a bushing of a chain by inserting a shaft, a pin and the like inside a tubular member.
In such a cylindrical bearing member, in order to improve the lubricity between the inner peripheral surface serving as the bearing surface and the shaft, pins, etc., lubricating oil parallel to the axial direction of the inner peripheral surface of the cylindrical bearing member is provided. A number of bottomed grooves that serve as oil reservoirs, in other words, a number of blind grooves for oil reservoirs are formed inside.

That is, a conventional cylindrical bearing member is formed by forming a blind groove for oil sump on the surface of a rectangular base material such as a steel strip or a flat belt by pressing, machining, or rolling, and then the rectangular base material is formed at both ends. It is manufactured by winding a cylindrical molded product (cylindrical member) with a molding machine so that the parts face each other, inserting a core punch into this cylindrical molded product, and pushing it through a circular opening die ( Patent Document 1).
Japanese Patent No. 2996352

  However, in the cylindrical bearing member manufactured in this way, the butted portion of the rectangular base material remains as a bus-line seam when the rectangular base material is wound, so that a shaft, a pin, etc. When the oil is inserted and used, the lubricating oil retained in the blind groove for oil sump tends to flow into the bus-line seam, and the lubricating oil that has flowed from the blind groove for oil sump flows from the longitudinal end of the bus-line seam. As a result, the cylindrical bearing member could not hold the lubricating oil for a long time and could not maintain the lubricating performance.

  It is also conceivable to weld the above-mentioned bus-line seam, but it is necessary to weld small articles such as chain bushes one by one, which not only requires a great deal of labor, but also a burrs after welding. This requires a heat treatment for taking off and taking a welding strain, which causes a problem that the manufacturing process becomes complicated and is not practical.

  Furthermore, since the blind groove for oil reservoir in the conventional cylindrical bearing member is formed on the inner peripheral surface of the cylindrical member by undercutting, broaching or the like, only one oil reservoir blind groove can be formed. However, there was a problem that the processing efficiency of the blind groove for oil sump was poor, and a long time was required for the processing, which was not suitable for mass production and was disadvantageous in terms of cost.

  Therefore, the problem to be solved by the present invention, that is, the object of the present invention, is to solve the problems of the prior art as described above. A cylindrical bearing member that can be retained and fully exerted a lubricating function, and a cylindrical bearing member that can efficiently mass-produce a blind groove for oil sump inside the cylindrical member at low cost. Is to provide a method.

  First, a cylindrical bearing member of the present invention according to claim 1 is a steel plate in which a number of blind grooves for oil sump are formed by press processing or roll processing, and the blind groove for oil sump is produced by a pipe-in-coil manufacturing method. The above-mentioned problem is solved by forming into a tubular member without the generatrix seam and cutting it to a predetermined length.

  Further, in the manufacturing method of the cylindrical bearing member of the present invention according to claim 2, after forming a large number of dimples to be oil retaining blind grooves on the surface of the steel strip by press working or roll working, By the coil manufacturing method, forming a cylindrical primary intermediate molded product in which both ends along the longitudinal direction of the steel strip are arranged in a cylindrical shape with the dimples inside and subjected to high frequency welding to eliminate the bus-line joint, The primary intermediate molded product is hot drawn to form a secondary intermediate molded product, and the secondary intermediate molded product is cold drawn to reduce the inner diameter relative to a predetermined axis. The above-mentioned problem is solved by forming a third intermediate molded product and then cutting the third intermediate molded product into at least a predetermined length.

  Here, the “blind groove” of the oil retaining blind groove as used in the present invention means a groove configuration in which at least both ends of the dimple formed by pressing or rolling are not open outward, in other words, The dimple formed by press working or roll working has a groove shape in which at least one end is sealed.

  In addition, the “pipe-in-coil manufacturing method” as used in the present invention means that an ERW steel pipe formed by high-frequency welding is heated in a continuous heating furnace, reduced in diameter by drawing and finished to a predetermined size. It is a method of winding a steel pipe in a coil shape.

  In the invention according to claim 1, a steel strip in which a number of blind grooves for oil sump are formed by press processing or roll processing is used to produce a bus-line seam with the blind groove for oil sump inside as a pipe-in-coil manufacturing method. By forming the lost tubular member and cutting it to a predetermined length, it is possible to eliminate the outflow of lubricating oil via the bus-line seam remaining during the winding process of the rectangular base material as in the prior art. When a shaft, pin, etc. are inserted into a cylindrical bearing member and used as a sliding bearing, the lubricating oil injected into the blind groove for oil sump is retained for a long time and the lubricating performance is sufficiently exhibited. In addition, since the dimples that become blind grooves for oil sump are continuously formed on the steel strip by pressing or rolling before the pipe-in-coil manufacturing method, the oil sump of the cylindrical bearing member for It is possible to form the grooves efficiently.

  And, the invention according to claim 2 is a cylinder by forming a large number of dimples to be oil retaining blind grooves on the surface of the steel strip by press working or roll processing before processing by the pipe-in-coil manufacturing method. A large number of dimples can be easily formed as blind grooves for oil reservoirs in the cylindrical bearing member, and the secondary intermediate molded product is obtained by hot drawing the primary intermediate molded product on which the dimples are formed. By forming, the processing distortion at the time of forming the dimple is eliminated, and the high frequency welded portion is assimilated and uniformed in the entire tubular member, so that the bus joint is substantially eliminated and the excellent workability is exhibited. be able to.

  In addition, this hot-drawn secondary intermediate molded product was cold-drawn to form a third intermediate molded product having a reduced diameter to the inner diameter opposite to the shaft, resulting in high strength and a beautiful surface roughness. Since the inner diameter of the cylindrical bearing member is almost the same, the multi-step process during finish forging is simplified, the operating efficiency of the forging machine is improved, the productivity is greatly improved, and mass production is performed at low cost. Can do.

  An embodiment of the present invention will be described with reference to FIGS. 1 is a perspective view of a cylindrical bearing member according to one embodiment of the present invention, FIG. 2 is a manufacturing process diagram of the cylindrical bearing member according to the present embodiment, and FIG. FIG. 4 shows a case in which press working is employed, wherein (a) is an aspect diagram during press working, (b) is a diagram showing a steel strip on which dimples after press working are formed, and FIG. When roll processing is adopted in this example, (a) is a view showing a state at the time of roll processing, (b) is a diagram showing a steel strip on which dimples after roll processing are formed, FIG. 5 is a view showing a modification of the dimples formed on the steel strip.

  First, as shown in FIG. 1, a cylindrical bearing member 100 according to an embodiment of the present invention is an inner part of a cylindrical member 120 in which a large number of oil sump blind grooves 121 are cut to a predetermined length. More specifically, it is formed on the peripheral surface 122, and more specifically, a steel strip in which a large number of such oil sump blind grooves 121 are formed by pressing is used to produce oil sump blind grooves 121 by a pipe-in-coil manufacturing method. Is a cylindrical member 120 that is formed into a tubular member without the bus-line joint and cut into a predetermined length.

Therefore, a method for manufacturing the cylindrical bearing member 100 of the present invention will be described below based on the manufacturing process diagram of the cylindrical bearing member shown in FIG.
First, a narrow steel strip 110 formed by slitting a wide steel strip (not shown) that has been hot-rolled is fed out of an uncoiler, and a large number of presses 300 are used on the surface of the fed steel strip 110. The dimple 111 is formed.
Then, a steel strip 110 in which a large number of dimples 111 are formed is supplied to a forming roll, and the tubular members are formed by sequentially aligning both end portions along the longitudinal direction of the steel strip 110 with the dimple 111 of the steel strip 110 inside. When the high-frequency welding apparatus (high-frequency induction heating coil) arranged so as to surround the outer periphery of the tubular member is passed through the high-frequency induction heating coil of the high-frequency welding apparatus, The two end portions along the line are sequentially aligned in a cylindrical shape, and are melt-bonded to each other by high-frequency induction heating and high-frequency welded, and formed into a cylindrical shape without a bus-line joint with a squeeze roll.
Thereafter, a bead of a welded portion generated on the inner and outer surfaces of the tubular member is cut by a cutting machine, so that a long primary intermediate molded product having a large number of dimples 111 formed on the inner surface is obtained.

  Here, in the formation of the dimple 111 in the present embodiment, a press machine 300 having a mold 310 having a long dimple convex portion 311 parallel to the traveling direction of the steel strip 110 as shown in FIG. Is used. Therefore, as shown in FIG. 3B, long dimples 111 having long grooves parallel to the longitudinal direction corresponding to the dimple projections 311 of the mold 310 can be formed in the band steel 110 at predetermined intervals. Finally, the oil sump blind groove 121 is sealed at the end in the longitudinal direction as shown in FIG.

  As described above, in this embodiment, the dimple 111 is formed by using the press 300, but a pair of rolls 410 having a large number of dimple convex portions 411 as shown in FIG. 4, and the circular dimples 411 can form the dimple 111 having a circular groove on the belt steel 110 as shown in FIG.

  Furthermore, other specific shapes of the dimples 111 formed in the steel strip 110 include a long groove inclined with respect to the longitudinal direction of the steel strip 110 as shown in FIG. ) And a combination of a long groove and a short groove parallel to the longitudinal direction of the steel strip 110 as shown in FIG. 5C, and the longitudinal direction of the steel strip 110 as shown in FIG. Various dimple shapes such as a short groove parallel to the direction can be adopted.

3 (b), FIG. 5 (b), and FIG. 5 (c), when the longitudinal ends of the oil sump blind groove 121 are all sealed, The cylindrical bearing member 100 can be measured from 110 to the groove length unit of the blind oil retaining blind groove 121. In this case, in the press machine 300 in which the mold 310 moves up and down, a large number of dimples 111 are formed while the strip steel 110 is repeatedly moved in units of the cylindrical bearing member 100, and the roll 410 of the roll machine 400 rotates while rotating. A large number of dimples 111 are sequentially formed for every 100 units of the cylindrical bearing member.
When the intermediate portion where the dimples 111 do not exist is cut at the time of cutting in the final process, the cylindrical bearing member 100 in a state where all the oil reservoir blind grooves 121 are sealed in the longitudinal direction is obtained.

On the other hand, a circular groove or short groove as shown in FIGS. 4B and 5D, or inclined or perpendicular to the longitudinal direction of the steel strip 110 as shown in FIG. 5A. In the case of the long groove, a dimple 111 may be formed continuously because a part of the oil sump blind groove 121 whose longitudinal end is sealed remains when it is cut to a bearing size.
The dimple 111 as described above is stretched and deformed in the state of a tubular member by the subsequent hot drawing and cold drawing, and is formed in the oil reservoir blind groove 121 having a desired dimple form. Therefore, the shape and distribution form of the dimple itself may be set in consideration of the drawing ratio during hot drawing and the drawing ratio during cold drawing.

Next, the first intermediate molded product made of the tubular member formed with the dimple 111 as described above is heated by a heating device, hot drawn by a multi-stage round roll, and then wound in a coil shape. It is taken to become a secondary intermediate molded product.
In other words, in this hot drawing process, the processing distortion at the time of dimple formation is eliminated, and the high-frequency welded portion is assimilated and uniformed in the entire tubular member, so that excellent processing in which the bus-line seam is substantially eliminated It becomes a secondary intermediate molded product that exhibits its properties.

Further, the second intermediate molded product made of the hot-drawn tubular member is supplied from a coil stand to a cold drawing device having dies arranged in one or more stages, and this cold drawing device uses a desired temperature. After being subjected to a drawing process for cold drawing so as to be reduced to an inner diameter opposed to the shaft, the coil is wound up into a third intermediate molded product.
The drawing process comprising the cold drawing improves the strength of the secondary intermediate molded product made of the tubular member, and the inner surface and the outer surface are homogeneous and excellent in properties.

Finally, after the third intermediate molded product made of a tubular member is cut into a predetermined length according to the size of the cylindrical bearing member 100, it is supplied to a cold forging device to perform chamfering and sizing. A desired cylindrical bearing member 100 is obtained.
Here, when the third intermediate molded product is cut into a predetermined length, the position of the oil sump blind groove 121 is detected in advance by a nondestructive inspection machine using an ultrasonic sensor or the like, and the detected data is If the cutting position is determined based on this, it is possible to accurately cut a portion where the oil reservoir blind groove 121 does not exist, and to maximize the effect of retaining the lubricating oil in the oil reservoir blind groove 121.
Therefore, in this embodiment, since the desired dimensions of the cylindrical bearing member 100 are already obtained before the cold forging process, for example, a 7 to 8 stage machining process is required from a conventional bar. Compared with the case of manufacturing by cold forging, in the case of the present embodiment, the cold forging process is simplified to 3 to 4 stages, and the final product can be completed with a small number of processes and cold. The operating efficiency of the forging machine can be increased, and wear of the forging tool required for cold forging can be reduced.

  In the cylindrical bearing member 100 of the present embodiment obtained as described above, the portion subjected to high-frequency welding is assimilated to the entire tubular member and becomes uniform, so that the busbar joint can be substantially eliminated. When a shaft, pin or the like is inserted into a member and used as a sliding bearing, the lubricating oil injected into the oil sump blind groove 121 can be held for a long time and the lubricating performance can be sufficiently exerted. Since the dimple 111 that becomes the blind groove 121 for oil sump is continuously formed on the strip steel 110 by press working or roll working before the pipe-in-coil manufacturing method, the cylindrical bearing member 100 has a desired blindness. The oil reservoir blind groove 121 having a groove shape can be efficiently formed, the multi-stage process during cold forging is simplified, the operating efficiency of the cold forging machine is improved, and the productivity is greatly improved. Low Such as can be mass-produced in the capital, the effect is enormous.

The perspective view of the cylindrical bearing member which is one Example of this invention. The manufacturing process figure of the cylindrical bearing member which is a present Example. It is a case where press work is employ | adopted as a present Example, Comprising: (a) is a mode figure at the time of press work, (b) is a figure which shows the strip steel in which the dimple after press work was formed. It is a case where roll processing is employ | adopted as a present Example, Comprising: (a) is a mode figure at the time of roll processing, (b) is a figure which shows the strip steel in which the dimple after roll processing was formed. The figure which shows the modification of the dimple formed in the strip steel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Cylindrical bearing member 110 ... Band steel 111 ... Dimple 120 ... Cylindrical member 121 ... Blind groove for oil sump 122 ... Inner peripheral surface 300 ... Press machine 310- .. Die 311 ... Dimple convex part 400 ... Roll machine 410 ... Roll 411 ... Dimple convex part

Claims (2)

  A steel strip in which a number of blind grooves for oil reservoirs are formed by pressing or rolling is formed into a tubular member with the blind grooves for oil reservoirs on the inside by pipe-in-coil manufacturing method, with no bus-line seams. A cylindrical bearing member characterized by being cut to a length of. After forming a large number of dimples that become blind grooves for oil sump on the surface of the steel strip by pressing or rolling, both ends along the longitudinal direction of the steel strip with the above dimples inside by pipe-in-coil manufacturing method The cylindrical intermediate intermediate product without the bus-line joint is formed by high-frequency welding while sequentially aligning the cylinders, and the intermediate intermediate product is hot drawn to perform secondary intermediate molding. A second intermediate molded product is formed by cold drawing to form a third intermediate molded product whose diameter is reduced to an inner diameter corresponding to a predetermined axis, and then the third intermediate molded product is formed. A method of manufacturing a cylindrical bearing member, comprising cutting a product into at least a predetermined length.

Images