JPS59120336A - Production of crank shaft - Google Patents

Abstract

PURPOSE:To straighten the band of a crank shaft by deburring the blank material for the blank shaft forged by forging dies then rolling and pressing the same with rolling rolls having rolls conforming to the journal parts of the crank shaft. CONSTITUTION:A round steel is heated and is forged to a blank material 11 for a crank shaft by forging dies. The burrs produced in this forging stage are removed by trimming dies. A bend is generated in the journal parts 12 of the material 11 from the devicated load and the uneven temp. distribution during cooling and the correction of the shape is required. Such material 11 is put between rolling rolls 9a, 9a rotated by a motor 6 and rolling rolls 9b as driven rolls and is rotated. The rolls 9a, 9b have the recessed grooves in the positions opposite to the journal parts 12 of the material 11 and the driven rolls 9b are pressed to said parts via a sliding head 5 by a hydraulic cylinder 4, whereby the bend in the journal parts 12 of the material 11 is straightened and the crank shaft having good accuracy in the balance is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a crankshaft with high precision.

When the round bar material is directly heated, or the large cup material is heated after being processed into a shape with good formability, and the crankshaft material 11 is forged with a forging die, the excess material is removed as shown in Fig. 1. Appears as Paris 13 on the side.

For this reason, prior to machining, this Paris 1 is
3 is removed by the trimming mold shown below (Fig. 2), but due to unbalanced loads during rimming and uneven temperature 4j during cooling, the crankshaft material 11 is often removed. A problem arises in that the journal portion 12 is bent.

In view of this problem, it is an object of the present invention to propose a new manufacturing method υ that corrects the bending, etc. that occurs in the material 11 after deburring, and forms a crankshaft with less imbalance.

That is, the present invention is characterized in that a crankshaft material that has undergone a deburring process is rolled by a roll having grooves on the outer circumferential surface disposed along the journal axis. The details will be explained based on the drawings.

FIG. 3 shows an example of an apparatus used in the method of the present invention, which includes a roll table 2 fixed to a base l'';
The slide shaft 5, which can be moved downwardly by the hydraulic cylinder 4 on the column 3, has two sliding shafts 7, 7 driven by a drive motor 6 and one driven shaft 8. Shafts are installed in the horizontal direction, and on each of these shafts 7 and 8 there are rolls 9a and 9b for rolling which have gate grooves on their outer circumferential surfaces.
Journal portion 1 of crankshaft material 11 to be formed
Corresponding to 2--It is attached inside the body. roll 9
As shown in FIG. 6, the groove 10 provided in the journal)'? Even when the rolls 9 are pressed and rolled against the journal portion 12 of the crankshaft material 11, the journal portion 12 is +11 due to the excess thickness. It is constructed so that it does not extend in any direction.

Next, to explain the V-forming method for crankshafts using a series of devices, the crankshaft material 11 formed by the forging die is removed in the next upper stage where the edges 13 protruding due to side forces are removed. Due to the trimming cutter, the clan shirt [・The side number of material 11 is Paris 13]
remains.

By the way, crankshaft material 1 that has undergone the above-mentioned process
1 is still in a high temperature state at this point, but if necessary, after reheating the material 11, the wooden drive roll 9
a, 9 Place the journal part 12 so that it is located at a-L, and then operate the hydraulic cylinder 4 from this 1- to make the slide hend 5 steeper and remove the tension 13 remaining in the journal part 12. A chestnut that expands toward the outer circumference when crushed? The driven roll 9b is rotated leaving the lance, and the driving roll 9a is rotated.

When the roll 9 rotates, for example, the crankshaft material 11ii for 4 cylinders receives the rolling action of the roll 9 on the journal portions 12 at five locations in the axial direction (Fig. 4), thereby deburring l', J'+ ! The bending of the material 11 that occurred in the step can be straightened. The remaining pads 13 of the journal portion 12 crushed by this rolling process-II are absorbed by the four portions 10 provided on the outer peripheral surface of the roll 9, and the elongation of the material 11 in the axial direction is prevented. (Figures 6 and 7).

As described above, according to the present invention, the forged crank shirt I material that has been deburred is rolled by the rolls provided on the journal tri along the journal axis, so that Not only can a well-balanced crankshaft be easily formed by correcting the bends that occur in the process 17, but also because rolls with grooves on the outer circumferential surface are used in this rolling process, the remaining surplus can be easily formed. This concave groove absorbs the axial elongation of the journal portion due to the meat, making it possible to ensure highly accurate molding.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of a crankshaft material formed by die forging, Fig. 2 is a diagram showing deburring processing of a crankshaft, and Fig. 3 is an example of an apparatus used in the method of the present invention. Figures 4 and 5 are a plan view and cross-sectional view showing the main parts of the same device, and Figures 6 and 7 are the state of the track being added by the I-device and the journal section after machining. FIG. 9a, 9b...Roll, 10...Concave groove 11...
... Crankshaft material 12 ... Journal Department Applicant Book) 1J Giken], Gyo Co., Ltd. Agent Patent Attorney Kei Nishikawa Figure 1 Figure 2 Figure 3 Δ

Claims (1)

[Claims] The process of removing the forged particles from the hot forged crank shirt I, and the process of removing the forged particles from the hot forged crank shirt I. A method for manufacturing crankshafts that involves positioning and rolling of the journal part of the crankshaft material.