JPH11277102A - Rolling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a rolled stock of desired square section by small number of calibers by providing a plurality of flat calibers in an alternately orthogonal to each other in a final finishing process, and alternately repeating the draft of a longitudinal side and a transverse side of an intermediate formed stock with the specified reduction of area using the flat calibers. SOLUTION: A round intermediate formed stock (a) is rolled down in the vertical direction using flat calibers F1 having a horizontal forming surface to obtain an intermediate formed stock (b). The intermediate formed stock (b) is rolled down in the right-to-left direction using flat calibers F2 having a vertical forming surface to obtain an intermediate formed stock (c). The intermediate formed stock (c) is rolled down in the vertical direction using flat calibers F3 having a horizontal forming surface to obtain an intermediate formed stock (d). The intermediate formed stock (d) is rolled down in the right- to-left direction using flat calibers F4 having a vertical forming surface to obtain an intermediate formed stock (e). The intermediate formed stock (d) is rolled down in the vertical direction using flat calibers F5 having a horizontal forming surface to obtain a final rolled product G. When the size is changed, the stroke of the flat calibers F1-F5 is changed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling method for obtaining a rolled product having a square or trapezoidal cross section suitable as a steel material for a ring gear of an automobile.

[0002]

2. Description of the Related Art FIG. 5 shows a ring gear of an automobile together with peripheral parts. In the figure, reference numeral 200 denotes the ring gear, and reference numeral 202 denotes a flywheel. 204 is a crankshaft, 206 is a piston, 208 is a balancer, and 210 is a starter motor. Here, the ring gear 200 is driven by the starter motor 210 when the engine of the automobile is started.
Is transmitted to the crankshaft 204 to start the engine.

Conventionally, as a method of manufacturing the ring gear 200, a method of sintering a powder and a method of cutting a rolled steel material into a ring shape by welding have been implemented. FIG. 6 specifically shows the latter manufacturing method. As shown in the figure, this method uses a roll straightening machine 216 while supplying a rolled steel (wire) 214 from a wire coil 212.
Then, a shot blast process is performed in the blast device 218, and thereafter, the steel material 214 is cut into predetermined dimensions by the cutting device 220. At this time, as shown in the figure, the cross-sectional shape of the steel material 214 is substantially trapezoidal.

Subsequently, the steel material 214 is formed into a ring forming machine 22.
2 to form a ring 224. In this ring forming step, since a tensile force acts on the outer peripheral portion of the steel material 214, the cross section of the ring 224 becomes quadrangular (square or rectangular) at this point. Then, the both ends are welded, and thereafter, the outer peripheral surface is subjected to the gear cutting process to make the ring gear 20.
Set to 0.

The ring gear 200 has many types and shapes depending on the type of vehicle.
4, that is, when rolling a rolled product, it was necessary to produce various sizes, and for this purpose, many types of holes were required in the rolling process.

[0006] In the case of the conventional rolling, in the final finishing rolling step, a diamond-shaped square-hole die is used for the intermediate rolled product.
The rolling process is performed by the square method, and in this case, a dedicated rhomboid-square hole type is required for each size, and thus a large number (type) of hole types is required.

FIG. 7 shows this concretely. The figure shows the respective steps of rolling when rolling nine types of rolled steel materials (rolled products) A to I. As shown in the figure, in the case of the rolled products A and B, the final finish rolling is performed. In the process, a diamond-shaped product and a square-shaped product dedicated to A and B corresponding to the diamond-processed product Da and the square-processed product Sa are required. In the case of the process-product C, the diamond-processed product Dc and the C corresponding to the square-processed product Sc are required. A special diamond hole type and square hole type are required. Further, also in the rolled product D, a diamond hole type and a square hole type dedicated to D corresponding to the rhombus processed product Dd and the square processed product Sd are required in the final finish rolling step.

[0008] Similarly, rolled products E, F, G, H, and I also have diamond-shaped processed products De, Df, Dg, Dh, and Dh, respectively.
A diamond hole type dedicated to E, F, G, H and I corresponding to Di, and a square hole type dedicated to E, F, G, H and I corresponding to square processed products Se, Sf, Sg, Sh and Si. I need. In this rolling process, each of the square processed products Sa to Si is finally formed into a quadrangular (square or rectangular) or substantially trapezoidal (tapered) cross section by a flat hole type or a taper type. You.

As described above, in the case of the conventional rolling method,
As the number of types of rolled products required increases, an extremely large number of special dies are required. For this reason, many dies and rolls must be retained, and the type is changed (rolling) in the rolling process. In such a case, the frequency of remodeling becomes high, and the rolling line must be stopped (stopped) during that time, thereby causing a disadvantage that the production efficiency is reduced.

[0010]

The invention of the present application has been made to solve such a problem. The rolling method according to the first aspect is a rolling method for obtaining a rolled product having a square cross-sectional shape, and alternately forms a right angle direction in the final finish rolling step with respect to the intermediate rolled product. Using a plurality of flat hole dies, vertical and horizontal reductions are alternately repeated at a predetermined area reduction rate, thereby obtaining a rolled product having a square cross section having a desired size.

According to a second aspect of the present invention, there is provided a rolling method for obtaining a rolled product having a substantially trapezoidal cross section. And a rolled product having a substantially trapezoidal cross section is obtained.

[0012] The rolling method according to the third aspect is the first or second aspect.
Wherein the rolled product is a steel material for a ring gear of an automobile.

[0013]

As described above, according to the first and second aspects of the present invention, a plurality of flat hole molds which are oriented at right angles to each other are used instead of using rhomboid molds and square hole molds in the final finish rolling step. The surface reduction processing is repeatedly performed by using to obtain a square or substantially trapezoidal rolled product having a finally obtained cross-sectional dimension.According to the processing method of the present invention, the reduction during the reduction by the flat hole mold is performed. By appropriately selecting the dimensions, it is possible to obtain rectangular or substantially trapezoidal rolled products of various sizes while using the same flat hole shape.

Therefore, according to the method of the present invention, it is not necessary to have an extremely large number of types of dies or rolls. It is only necessary to change and adjust the size, and it is possible to eliminate or significantly reduce the type change operation including the change of the hole shape or roll as in the conventional processing method, thereby increasing the production efficiency and the cost required for the production. Can be reduced, and it is also possible to quickly respond to a new size. In the present invention, the vertical surface and the horizontal surface mean surfaces that are at right angles to each other, and do not necessarily mean the vertical surface and the horizontal surface. The working method of the present invention is particularly suitable when applied to rolling of a steel material for a ring gear of an automobile (claim 3).

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 conceptually shows the working method of the present embodiment. As shown in the drawing, in the working method of the present embodiment, a plurality of intermediate or round or oval intermediate products are alternately formed at right angles. The upper and lower surfaces and the left and right surfaces in the figure are successively pressed down in the vertical and horizontal directions using a flat hole die, and by repeating this process, a square-shaped processed product →→→
To obtain a final rolled product having a square cross section. Alternatively, a square-shaped processed product is processed using a tapered hole die to obtain a final rolled product having a tapered cross section (substantially trapezoidal shape).

That is, in the case of the conventional processing method, as shown in FIG. 1, the processing is performed in the order of a diamond-shaped workpiece D → a square-shaped workpiece S using a diamond-hole type and a square-hole type. In the method of the present embodiment, a square rolled product or a tapered (substantially trapezoidal) rolled product is obtained using a tapered hole type. The rolling of the upper and lower surfaces and the left and right surfaces in the figure is alternately and repeatedly performed by using a mold to finally obtain a rolled product having a desired cross-sectional dimension.

FIG. 2 shows a rolled product A similar to that shown in FIG.
1 is a diagram illustrating a specific rolling method of the present embodiment for obtaining 〜I. Here, the rolled products A to I are all rolled steel materials for the ring gear 200 described above.

In the working method of this embodiment, starting from a raw material (wire material) made of, for example, S45C (having a size of, for example, 155 mm square), rough rolling and intermediate rolling are performed. → Obtain an intermediate processed product through key. Alternatively, an intermediate processed product is obtained from u through ke → ko → sa. These steps are the same as the conventional processing method shown in FIG.

In the working method of the present embodiment, when it is desired to obtain, for example, rolled products F and G, flat hole dies having a horizontal forming surface and flat hole dies having a vertical forming surface are alternately arranged. Through which the upper and lower surfaces and the left and right surfaces are alternately pressed down in the vertical and horizontal directions. Get G.

Alternatively, when it is desired to obtain a rolled product H, the upper and lower surfaces and the left and right surfaces of the intermediate processed product are similarly obtained by using a flat hole die having a horizontal forming surface and a flat hole die having a vertical forming surface. Are sequentially and alternately reduced, so that a square-shaped processed product d → nu → ne → no passes through to the final square-shaped rolled product H
Get.

Similarly, when it is desired to obtain a rolled product I, the lower and upper surfaces and the left and right surfaces of the intermediate processed product C are repeatedly and successively and alternately reduced by a flat hole die, thereby forming a square shape. The final square-shaped rolled product I is obtained through the following processes. Note that in FIG.
Although D and H are represented by square shapes, as will be clarified later, the processed products H, D and H have strictly bulged left and right sides in a slightly curved shape.

Here, from the intermediate processed product to the final rolled product F,
The flat hole die for obtaining G, the flat hole die for obtaining the final rolled product H from the intermediate processed product U, and the flat hole die for obtaining the final rolled product I from the intermediate processed product C are all The same flat hole mold can be used. The rolling size can be freely and appropriately adjusted simply by appropriately adjusting the rolling gap such as the roll gap and the rolling reduction amount, and the rolled products F, G, H, and I of various sizes can be obtained by the adjustment. You can do it.

The rolled products F, G,
When H and I are formed into a ring shape, the width dimension differs between the outer peripheral portion and the inner peripheral portion. The deformation of the cross section due to the ring molding can be corrected by applying a press straightening machine.

On the other hand, when it is desired to obtain tapered (substantially trapezoidal) rolled products A, B, C, D, and E, a flat hole die having a vertical forming surface in the same manner as the intermediate processed product is used. ,
Using a flat hole die with a horizontal molding surface to sequentially and alternately press down the left and right sides and the upper and lower surfaces repeatedly to obtain a processed product through a process → a process, and then to process using a tapered hole die By the final tapered (trapezoidal) rolled product A,
B, C, D and E are obtained. In obtaining the rolled products A to E, the same flat hole die as that for processing the rolled products F, G, H, and I can be used.

FIG. 3 shows a processing method for processing the above-mentioned rolled product G more specifically as an example. As shown in the figure, when processing the rolled product G, first, a round processed product is vertically lowered (rolled) using a flat hole die F1 having a horizontal forming surface, and then processed. Get the product. The cross-sectional shape of the processed product is shown in detail in FIG.

Next, using a flat hole mold F2 having a vertical molding surface, the left and right surfaces of the processed product are pressed down in the left-right direction to obtain a processed product. Subsequently, the processed product is pressed down in the vertical direction using a flat hole die F3 having a horizontal molding surface, thereby obtaining a processed product. Subsequently, the left and right surfaces of the processed product te are pressed down in the left-right direction using a flat hole die F4 having a vertical molding surface, thereby obtaining a processed product. Finally, using a flat hole die F5 having a horizontal forming surface, the processed product is vertically lowered to obtain a final rolled product G.

FIG. 4 shows, by way of example, the shape and dimensions of each step when the rolled product G is rolled, and the area reduction rate. As shown in the figure, the upper and lower flat surfaces and left and right flat hole types are used to sequentially and alternately repeat the rolling of the upper and lower surfaces and the left and right surfaces to gradually reduce the cross-sectional dimensions. Finally, it is possible to obtain a rolled product G having a desired dimension, that is, a vertical dimension 14.2 mm and a horizontal dimension 19.4 mm in this case.

As described above, according to the processing method of the present invention,
By appropriately selecting the rolling dimension by the flat hole die, it is possible to obtain the square rolled products F to I or the substantially trapezoidal rolled products A to E of various sizes while using the same flat hole die.

Therefore, according to the present embodiment, it is not necessary to have an extremely large number of types of holes or rolls, and even when the size is changed during rolling, the reduction dimension of the flat holes is simply changed appropriately. It is only necessary to make adjustments, and it is possible to eliminate or significantly reduce the type change operation including the change of the hole shape or roll as in the conventional processing method. Thereby, the production efficiency can be increased, and the cost required for production can be reduced.

Although the embodiment of the present invention has been described in detail, this is merely an example, and the present invention can be implemented in various modified forms without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is an explanatory view conceptually showing a method of one embodiment of the present invention in comparison with a conventional example.

FIG. 2 is an explanatory view specifically showing a method of one embodiment of the present invention.

FIG. 3 is a diagram more specifically showing a method of rolling the rolled product G in FIG. 2;

FIG. 4 is a diagram showing a change in shape, a dimension, and a reduction in area of a processed product in each step when the same rolled product G is obtained.

FIG. 5 is a diagram showing a ring gear of an automobile together with peripheral parts.

FIG. 6 is a view illustrating a method of manufacturing the ring gear of FIG. 5;

FIG. 7 is an explanatory view of a rolling method for obtaining steel materials of various sizes for the ring gear in FIG.

[Explanation of symbols] ,,, processed products, rolled products a. Raw materials (wires) a, c, d, o, ka, ki, k, ke, ko, sa, shi, intermediate processed products A, B, C, D, E, F, G, H, I Rolled products F1, F2, F3, F4, F5 Flat hole type

Claims (3)

[Claims] 1. A rolling method for obtaining a rolled product having a quadrangular cross-sectional shape, wherein a plurality of flat hole dies having alternately perpendicular directions are used in a final finishing rolling step for an intermediate rolled product. A rolling process wherein a vertical surface and a horizontal surface are alternately and repeatedly reduced at a predetermined area reduction ratio, thereby obtaining a rolled product having a square cross section having a desired size. 2. A rolling method for obtaining a rolled product having a substantially trapezoidal cross-sectional shape, wherein rolling is performed using a tapered hole die at or after the final processing step in claim 1,
A rolling method comprising obtaining a rolled product having a substantially trapezoidal cross section. 3. The rolling method according to claim 1, wherein the rolled product is a steel material for a ring gear of an automobile.