JPS6326229A - Forging method for segment sprocket - Google Patents

Abstract

PURPOSE:To obtain a forged product of small machine finishing by punching excess metal and bend correcting a semiprocessed product die forged bending a tooth form from regular size taking draft angle into consideration in a trimming process, and then coining the tooth form part by a sectional die. CONSTITUTION:The tooth face 2 of the rib 60 of a die is engraved parallel to the excess metal face 1, and tooth forms 26, 27 are deformed to tooth forms 28, 29 made wider than regular circular arc 3 taking draft angle into consideration. in a trimming correcting process, excess metal 1 is punched by the outer edge of an operating upper die and the inner edge of a trimming die, and the forged product 51 is bent again to regular size. In a coining process, the forged product 51 is placed at a specified position 45 of the lower die 39, and regular tooth form is engraved on the tooth face 2. Sectional dies 41, 41' having two tapered 42 faces 46, 47 are put in a tapered part 43 of the lower die 39, and the upper face 50 is forge pressed and formed by the upper die 49. Thus, a forged product of segment sprocket small in number of machine finishing processes is obtained.

Description

[Detailed Description of the Invention] Conventional forging methods for segment sprockets are usually 0 horizontal hammer type, 1 vertical rod type, and 2''' (6o) Figure 1 shows a curved one using horizontal rod type! K A plan view of the forged product with five teeth.

FIG. 2 is a sectional view taken along the line B-E'. FIG. 3 is a plan view of the vertical rod type forged product. FIG. 4 is a sectional view taken along the line C-σ. In order to use this horizontal rod-type forged product as a machine part, the extra thickness (6) generated during die forging, the five tooth surfaces (7), and both sides t81 (91, both ends of the flange) Surface αυQ2
Also, machining of bolt holes Q3, etc. is required.

In addition, in the vertical rod type, due to the work process, the mold is
1S are made parallel, and both end faces αea′O require a draft due to their shape, so it is necessary to add a thickness 0809 for the draft. Therefore, in this construction method, the required clearance for the work is Meat αII (11 as well as both sides of the flange ■2D
, requires machining such as Q4 (c) on both sides of the tooth.

The method according to this patent aims to eliminate the counterfeit finishing process as much as possible and reduce the product price of segment/sprocket forged products. In FIG. 6, D- is a cross-sectional view.

tL! 1. For the forged product, the tooth surface (2) is parallel to the young flesh surface (1) K.5KL, both ends 14) (5) The outer tooth profile near K widens outward, and the selection gradient is applied during die forging. To the extent that there is a draft angle! 3) Expand the arc of the regular dimensions of the forged product. In other words, the regular dimension tooth type (to) fin is bent in advance to the dotted line tooth type (support) (g) and SI construction is performed, and then the tooth type (to) is restored by being straightened again. FIG. 8, which is a plan view of a mold for a forged product, is a sectional view of a trimming straightening mold and shows its working process. That is, the figure on the left after crossing the Mu X-rays shows the trimming correction of the forged product (32);
Of course, the outer circumferential shape is the regular size.

In order to improve the regular dimensional accuracy of IN & forged products in every detail, an inning process is performed as a second method based on this patent.

The reason for 9149 is the bottom plan view of the coining body, No. 10.
The figure is an El-R' cross-sectional view, and FIG. 11 is a y-yt' @ side view of the coining lower metal cradle (44). Fig. 12 is a plan view of the mold 0 Fig. 15 is a G-ge cross-sectional view of the coining process 0 The predetermined part r6 (as
) K space, seven regular tooth patterns are carved into the outer tooth pattern surface, and the surface is also two surfaces (46 x 47) K taper (42). (43) Insert Ic and this wari piece (41X4
0 arrow (r!>Iz dog mark (1+)) Press and mold the upper surface (50) of 1 in the direction of arrow (54) by j19 with the upper mold (49) that has a mold engraving required for tΔ tight forging. nignow'
rπηΣ 工τ.

This patent applies to forged products that are coined! lf! Figure 5Figure 6Figure 6Illustrated Figure 6The shape of the mold has a complex tooth pattern and is curved in an arc throughout, so it is difficult to apply uniform pressure to the product surface with a one-piece mold. , Warikoma (
41) (41) By press-fitting the mold! # *
After the coining process is completed, the warikoma (
Use several knock bottles (48) at the bottom of the 41X41 to push up the Warikoma (41X41) using air pressure or hydraulic pressure.
Easily coin the forged product (51) into the mold body (39)
This construction method is characterized by being able to take out more.

[Brief explanation of drawings]

Figure 1 is a plan view of a segment sprocket with 5 teeth made using the conventional horizontal rod type forging method. FIG. 3 is a plan view of the modified product. Figure 4 is a 0-σ cross-sectional view of the forged product.
The figure is a plan view of the forged product according to this patent. FIG. 6 is a D-go sectional view of the forged product. FIG. 7 is a plan view of the forging die. i 81'4 is a cross-sectional view of the trimming straightening mold.
An explanatory diagram showing the effect of the trimming correction mold on the left and right side of the ' line.

Claims (1)

[Claims] The present invention relates to a forging method for manufacturing a segment sprocket by forging a forged metal material. The forged product of the first construction method segment sprocket has a shape in which several tooth patterns protrude in a line on the outer edge of a curved rib, and since several of the tooth patterns have a reverse draft angle, the curvature of the forged product A method in which die forging is performed by widening the radius, then the excess metal is removed, trimming is performed to make the shape regular, and the pre-curved forged product is straightened. 2nd method A method of performing a coining process using a piece mold in which the tooth part is divided for precisely correcting the detailed shape and dimensions of the forged product that has gone through the steps described in the first method. This invention is characterized in that precision forging is performed by sequentially implementing each of the above methods. The first method was applied for conversion to a separate patent application (1) (Showa 5
2008 Utility Model Registration Application No. 203943), filed at the same time as this patent application (2). Therefore, the second construction method is a forging construction method for a segment sprocket according to the claims of the present invention.