JPH0538546A - Method for forge-forming hausing raw material for ball joint - Google Patents

Abstract

PURPOSE:To forge a hausing raw material for high quality ball joint by backward extrusion-forming into a cup shaped raw material after forward extrusion- forming the necessary length of a columnar raw material into a raw material with flange. CONSTITUTION:The forward extrusion-forming is executed to the columnar raw material 1 cut to a round bar of the necessary length into the raw material 11 with flange, having almost the same inner diameter hole as inner diameter of opening part in the hausing raw material to be formed and the flange part 12 projecting as circular outward in the outer peripheral part. Successively, the backward extrusion-forming is executed to the material into the cup shaped raw material composed of cylinder part having almost the same length in axial direction as length of the hausing raw material to be formed and a stepped inner diameter edge part. By this method, the quality and the dimensional accuracy at the time forge-forming the hausing raw material for ball joint, can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forging a housing rough material of a ball joint used in, for example, an automobile steering system and a suspension system.

[0002]

2. Description of the Related Art Conventionally, as a method of forging a housing rough material 131 for a ball joint as shown in FIG. 6D, it was made as shown in FIGS. 6A to 6D. .. That is, the columnar columnar material 101 ((a) in FIG. 6) obtained by cutting the round bar material to the required length in the first step is replaced with the cup-shaped rough material 111 ((b) in FIG. 6) having a bottomed cup shape. Then, in the second step, the cylindrical rough material 12 is obtained by punching out the approximately center of the bottom 113 of the cup-shaped rough material 111 by a punching punch in the second step.
1 ((c) in FIG. 6), and subsequently, in the third step, the large opening 122 of the cylindrical coarse material 121 is installed, and a circle is formed from the outer diameter portion near the large opening 132 toward the outside. An annular flange portion 132a protruding circumferentially and an inner peripheral surface 1 of the large opening portion 132
35 'and the housing rough material 131 which has the step-shaped inner diameter edge part 134 continuously.

[0003]

In the method for forging a housing rough material for a ball joint as described above, as shown in FIG.
Large opening 1 of cylindrical rough material 121 as shown in (c) of FIG.
When 22 is set up and molded into a housing 131 having an annular collar portion 132a and a stepped inner diameter edge portion 134 as shown in FIG. 6D, the collar portion 132a is forced by the punch and the upper and lower molding dies. 6A, the metal flow 10F from the outer peripheral portion of the large opening portion 132 toward the inner side is generated, and the collar 10A of FIG. An annular recess 13 is formed on the outer peripheral surface of the portion 132a.
8 is formed, and the folding ring 139 at the time of upsetting is formed on the inner diameter surface 135 ′ of the large opening 132.

Further, at the stepped inner diameter edge portion 134, the metal flow 10F is poorly coupled, and the strength tends to decrease. Therefore, at the time of assembling the ball joint, the inner diameter edge portion 134 is covered with the closing plate and caulked and fixed, but the inner diameter edge portion 1 is caused by the tensile load applied to the ball joint.
There is a problem that 34 is missing and the closing plate is loosened.

Further, since the forming is forced, the life of the punch and the upper and lower forming dies is shortened.

Therefore, according to the present invention, the metal flow of the housing rough material having the annular flange portion and the step-shaped inner diameter edge portion is good, and the punch and the upper and lower molding dies can be held easily. It is intended to provide a forging method.

[0007]

[Means for Solving the Problems] A cylindrical columnar material obtained by cutting a round bar into a required length has a hole portion having an inner diameter substantially equal to the inner diameter of the opening portion of a housing rough material to be molded, and the vicinity of the hole portion. A flanged rough material having an annular flange portion that projects circumferentially toward the outside on the outer periphery is extruded forward, and then the flanged rough material is approximately the same axial length as the housing rough material to be molded. A step of backward extrusion molding into a cup-shaped rough material having a cup shape with a bottom, which has a cylindrical portion having a height and an inner peripheral surface of the hole portion and which has a stepped inner diameter edge portion.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 2 and 3 showing the forging device in the main process of the housing forming process, the left half of each drawing shows the state before forging, and the right half shows the state after forging.

In forging the housing raw material 31 for a ball joint, a round bar having a diameter substantially the same as the desired diameter of the housing raw material 31 is cut in advance to a required length to form a columnar material 1 having a required volume. ((A) of FIG. 1) is prepared.

First, in the first step, the columnar material 1 is subjected to rearward extrusion molding by punching, and the hole portion 15 having an inner diameter substantially equal to the inner diameter of the opening portion of the housing rough material 31 to be molded and having a relatively shallow axial length is formed. And the flanged rough material 11 ((B) in FIG. 1) having an annular flange 32 that protrudes outward in the circumferential direction on the outer peripheral portion near the hole 15. Next, in the second step, the flanged rough material 11 is punched to have a cylindrical portion 26 approximately equal to the axial length of the housing rough material 31 to be molded, and the inner peripheral surface 25 ′ of the hole 25.
Is continuously extruded into a cup-shaped rough material 21 ((C) in FIG. 1) having a bottomed cup shape having a step-shaped inner diameter edge portion 24. Subsequently, in the third step, the substantially center of the bottom portion 23 of the cup-shaped rough material 21 is punched out by a punching punch (not shown) to form a pierce hole 37 and a flange-shaped small opening 33 that forms the periphery of the pierce hole 37. A rough housing material 31 having (1) and (2) in FIG. 1 is formed.

Among the above-described molding steps of the housing rough material 31, the first step and the second step which are the points of the present invention will be described.

FIG. 2 shows an apparatus 60 for forming the collared rough material 11 in the first step. The structure of this device will be described with reference to the drawings. Reference numeral 61 is a punch, which has a large intermediate diameter portion 62 having substantially the same diameter as the flanged coarse material 11 to be formed, and a small diameter flange which is continuous with the intermediate large diameter portion 62. It is composed of a lower end portion 63 having substantially the same shape as the hole 15 of the attached rough material 11. An upper die 65 fixes the punch 61 and is held by an upper substrate 64 located above, and the upper substrate 64 is further fixed by an upper holder (not shown).
Further, reference numeral 66 is a lower die, and a die engraving portion 69 including a large diameter hole portion 70 for receiving the columnar material 1, and a small diameter hole portion 72 continuous to the large diameter hole portion 70, and a lower step of the die engraving portion 69. The portion 74 is provided with a continuous counter hole 73, and a counter punch 68 is fitted in the counter hole 73. A lower substrate 67 fixes the lower die 66 and is fixed by a lower holder (not shown).

When the collar material 11 is formed by the forging device 60 having the above-described structure, first, the cylindrical material 1 is inserted into the die engraving portion 69 of the lower die 66 as shown in the left half of FIG. 69
The large-diameter hole 70 is supported by the step 71. Subsequently, as shown in the right half of FIG. 2, the punch 61 is lowered integrally with the upper die 65, and the columnar material is formed between the die engraved portion 69 of the lower die 66 and the intermediate large diameter portion 62 of the punch 61. The upper end surface of 1 is pressed to form the collared material 11 having the desired hole 15 and collar 12. After that, the punch 61 rises to a predetermined position, and subsequently, the flanged material 11 formed is extruded upward by the counter punch 68 and taken out.

FIG. 3 shows an apparatus 80 for forming the cup-shaped material 21 in the second step. The structure of this apparatus will be described with reference to the drawings. Reference numeral 81 indicates a lower end portion 83 of the cup-shaped material 21 to be formed by punching, and a lower end portion 8 of the distal end portion 8 having substantially the same diameter.
3 and an intermediate portion 82 having a smaller diameter. An upper die 85 fixes the punch 81, and is held by an upper substrate 84 located above, and the upper substrate 84 is further fixed by an upper holder (not shown). Further, reference numeral 86 is a lower die, which is provided with a die engraving portion 89 that receives the collared rough material 11 and has a desired forming shape, and a counter hole 92 continuous to the lower step portion 93 of the die engraving portion 89. A counter punch 88 is fitted in the. A lower substrate 87 for fixing the lower die 86 is fixed by a lower holder (not shown).

When the cup-shaped rough material 21 is formed by the forging device having the above-mentioned structure, first, the die-slot 8 is formed as shown in the left half of FIG.
The collared rough material 11 is inserted into 9 and the collar portion 12 is supported by the step portion 90 above the die carving portion 89. Then punch 81
3 is lowered integrally with the upper die 85 to squeeze the inner peripheral surface 15 'of the flanged coarse material 11 with the lower end portion 83 of the punch 81 to press the bottom portion 13 having a relatively large thickness, and the right portion of FIG. As shown in the half part, a desired housing rough material 31 to be molded is extruded backward from a cylindrical portion 25 having a substantially equal axial length, and a stepped inner diameter is formed continuously with the inner diameter surface 25 ′ of the hole 25. The bottomed cup-shaped rough material 21 having the edge portion 24 is formed.

After the cup-shaped rough material 21 is taken out from the molding device 80, as described above, the center of the bottom portion 23 is punched out to form a pierce hole 37 and a flange-shaped small opening portion 33 forming the periphery of the pierce hole 37. Housing rough material 31 having
((D) in FIG. 1). Then, the inner diameter surface 35 ′ of the hole 35 of the rough housing material 31 is replaced with a plurality of stepped inner diameter surfaces 4
5'is molded into the stepped component 41 ((e) in FIG. 1), the burr 48 is removed, and the housing is finished into a desired shape ((f) in FIG. 1).

Further, as another embodiment, a thin annular caulking portion is formed at the end of the housing as shown in FIG.
As shown in FIG. 5, after the housing rough material 31 of the third step ((d) of FIG. 5) is molded by the molding method of the present invention, the flange portion 32 of the housing rough material 31 is fixed to the annular caulking portion 42b and the outer periphery. It may be formed in the collar portion 42a. Further, in the extrusion molding process of either the first or second process described above, the collar portions 12 and 22 may be molded in advance into such a desired shape.

Therefore, an annular flange having an inner diameter substantially equal to the inner diameter of the opening of the housing rough material to be formed in advance and having an annular flange portion projecting outward in the outer peripheral portion near the hole is formed. After molding, a cup-shaped rough material having a cylindrical portion having a length substantially equal to a desired housing rough material in the axial direction together with a step-shaped inner diameter edge portion continuous with the inner peripheral surface is extruded backward, As shown in FIG. 4 in which (A) is enlarged, the metal flow F in the large opening of the housing becomes better than in the conventional case. Further, the molding pressure applied to the molding punch and the die is reduced.

[0019]

As described above, according to the present invention, since the metal flow in the vicinity of the large opening portion of the housing is good, annular recesses are not formed on the outer peripheral surface and the inner peripheral surface of the collar portion. The housing can be molded with high quality accuracy and high strength of the stepped inner diameter edge. Further, since the molding pressure applied to the molding punch and the upper and lower dies is reduced, the life of the punch and the upper die is also improved.

[Brief description of drawings]

FIG. 1 is a process drawing showing a forging process of a ball joint housing according to an embodiment of the present invention.

FIG. 2 is a partial plan cross-sectional view of a forging device for forming the flanged rough material shown in FIG.

3 is a partial plan sectional view of a forging device for forming the cup-shaped rough material shown in FIG.

FIG. 4 is an enlarged view showing a metal flow state of a portion A in FIG.

FIG. 5 is a process drawing showing a forging process of a ball joint housing according to another embodiment of the present invention.

FIG. 6 is a process drawing showing a forging process of a conventional ball joint housing.

FIG. 7 is an enlarged view showing a metal flow state of a 10A portion in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical material 11 Collared rough material 12 Collar part 15 Hole part 21 Cup-shaped rough material 23 Bottom part 24 Inner-diameter edge part 25 Hole part 25 'Inner-diameter surface 26 Cylindrical part 31 Housing rough material 81 Punch

Claims (1)

[Claims] 1. A cylindrical column material (1) obtained by cutting a round bar into a required length, and a hole (15) having an inner diameter substantially equal to the inner diameter of the opening of the housing rough material to be molded in the first step. And has a flanged rough material (11) having an annular flange portion (12) projecting outward in a circumferential direction on the outer peripheral portion near the hole portion (15), and then extrusion-molding the raw material. In two steps, the flanged rough material (11) is formed together with the tubular portion (26) having a length in the axial direction substantially equal to that of the housing rough material to be molded, and the hole (2
5) is continuous with the inner peripheral surface (25 ') and has a stepped inner diameter edge (2
4) A cup-shaped rough material (21) having a cup shape with bottom is extruded backward, and a method for forging a rough material of a housing for a ball joint.