JP2002011540A - Method and tool for manufacturing forged aluminum alloy parts for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a tool for manufacturing a forged aluminum alloy parts for automobile in which the machining speed is high even when the machining accuracy of a prepared hole of a boss is maintained, the machining is easy, the surface area of chips is small after the machining, and the recyclability of chips is excellent. SOLUTION: This manufacturing method of the forged parts for automobile comprising a plurality of bosses 12 and 13 to be engaged with a counter member and a connection part 10 continuous to the bosses and having through holes holding different direction in the bosses thereof comprises a first step for forging an aluminum alloy ingot of a predetermined size into the aluminum alloy forged parts for automobile of a predetermined shape by a press, a second step for fixing the aluminum alloy forged parts for automobile by a die-like fixing means, and a third step for punching the through holes 12a and 13a in the fixed bosses by using a perforating punching tool 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a forged part for an aluminum alloy automobile forged from an aluminum alloy and a tool for manufacturing the same.

[0002]

2. Description of the Related Art In general, undercarriage parts such as suspension arms are being replaced with aluminum alloys from iron-based alloys in order to reduce the weight of automobiles. These underbody parts are mainly made of a 6000 series aluminum alloy material, and are processed into forged parts of aluminum alloy automobiles having a desired shape by forging.

[0003] This type of forged part for an aluminum alloy automobile has a plurality of bosses at its free end for engaging with other parts, and a connecting part continuous with these bosses. In the boss portion, a through hole is formed as a pilot hole, and after finishing the through hole, a bush or the like is fitted and used.

Some of the aluminum alloy forged parts for automobiles having the above-described structure have different through holes of the boss in directions different from each other, such as suspension arms. After the forging process, they are manufactured faithfully because they cannot be machined, and after drilling each hole by drilling etc., forming a through hole, and then finishing it to a predetermined shape with an appropriate cutting tool to commercialize it. It is.

[0005]

However, the conventional method of manufacturing a forged part for an aluminum alloy automobile has the following problems.

That is, when forming a through hole of a boss portion in a forged part for an aluminum alloy automobile, since a pilot hole is formed by a drill, the center portion of the drill becomes a non-cutting blade and the chip discharge property. Is very bad, the cutting rate is low and the processing time is long. In the case of preparing a pre-drilled hole with a drill, if a convex surface is formed on the machined surface, not only the biting property is extremely poor, the workability is reduced, but also the drilling accuracy is poor.

When drilling a hole with a drill, the position of the boss is located at the free end, so that the connecting portion having a small cross-sectional area is easily bent during drilling the hole, so that the straightness and concentricity are improved. This has had an adverse effect.

[0008] Further, when preparing a pre-drilled hole by a drill without impairing the required processing accuracy, the processing time is further increased.

On the other hand, since aluminum alloys are more expensive than iron-based alloys, there is a growing demand for recycling especially recently. However, chips from drilling are
Since the cutting oil is supplied to perform the drilling without generating the cutting heat, a large amount of the cutting oil is attached, and the chips cannot be re-dissolved as it is. Chips produced by drilling had a large re-dissolution loss because they had a large surface area and were easily oxidized as compared with lump. Since the chip has a large surface area, the chip may be ignited, which is disadvantageous because it has a risk factor.

The present invention has been made in view of the above problems, and has a high processing speed even in a state in which the processing accuracy of the prepared hole of the boss is maintained, and the processing operation is easy. It is an object of the present invention to provide a method for producing a forged part for an aluminum alloy automobile having a small chip surface area and excellent chip recyclability, and a production tool therefor.

[0011]

In order to solve the above-mentioned problems, the present invention has the following arrangement. That is, a method for manufacturing a forged part for an aluminum alloy vehicle, comprising a plurality of bosses for engaging with a mating member and a connecting portion continuous to these bosses, wherein the directions of through holes of the bosses are different. A first step of forging an aluminum alloy ingot formed into a predetermined size into a predetermined shape of the aluminum alloy automobile forged part by a pressing device; and forming the forged aluminum alloy automobile forged part. The method comprises a second step of fixing with a die-shaped fixing means, and a third step of forming a through hole in the fixed boss of the aluminum alloy automobile forged part by punching using a punching tool.

[0012] With this configuration, the boss portion cannot process all the through holes in the forging process due to the different orientations of the through holes. In a state of being fixed by the means, a through pilot hole is formed by punching with a punching punch tool.
The chips at this time become a columnar bulk.

[0013] Further, the punching tool for punching described in the method for manufacturing a forged part for an aluminum alloy automobile has a cutting edge provided on a distal end side of a cylindrical body and a mounting base end provided on a rear end side of the cylindrical body. A tool for producing a forged part for an aluminum alloy automobile having a flank formed on the cutting edge.

With this configuration, it is possible to sufficiently process the through hole in the boss portion even if the diameter is large and the processing thickness is large.

Further, in the punch for punching described in the method for manufacturing a forged part for an aluminum alloy automobile, a cutting edge having a flank is provided at a front end side of a cylindrical body, and a mounting base end provided at a rear end side of the cylindrical body. And an aluminum having a step at a middle diameter of the cylindrical body, a step having a diameter different from that of the cylindrical body, a cutting edge of a finishing punch having a diameter larger than the diameter of the tip side, and a flank formed at the cutting edge of the finishing punch. Used as a tool for manufacturing forged parts for alloy vehicles.

With this configuration, the pilot hole formed once by the cutting edge formed at the tip of the punch can be finished by the finishing punch at the intermediate position by a series of operations of the punch.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) and 1 (b) are a side view and a front view showing an example of a forged part for an aluminum alloy vehicle, FIG. 2 is a plan view showing a production tool for a forged part for an aluminum alloy vehicle, and FIGS. 3 (a) and (a). 4B is a cross-sectional view showing a main part of a mold-shaped fixing means for fixing a forged part for an aluminum alloy vehicle, and FIGS. 4A and 4B are side views showing a punching tool for punching a forged part for an aluminum alloy vehicle. FIG. 5 is a block diagram showing a process of manufacturing a forged part for an aluminum alloy automobile, and FIG. 6 is a partially cutaway side view showing another configuration of a punching punch tool.

As shown in FIGS. 1 and 2, a work W such as a suspension arm, a link member, or a knuckle is used as a forged part for an aluminum alloy automobile.
Is made of an aluminum alloy. As the aluminum alloy used here, a 6000 series aluminum alloy is mainly used, but other aluminum alloys used for automobiles may be used.

The work W has a boss 1 at its upper and lower free ends.
1, 12 and 13 are formed, and the through hole 11a of the upper boss 11 and the through hole 12a of the lower boss 12 and 13 are formed.
The a and 13a are formed so as to face in directions different from each other by 90 degrees, and are integrally formed by a substantially L-shaped connecting portion 10. This work W is formed by forging.

As described above, the through hole 11a of the boss 11
If the orientations of the through holes 12a, 13a of the boss portions 12, 13 are different, one of the through holes 12a, 13a is used in the forging process.
13a (11a) cannot be formed, and it is necessary to perform drilling on the forged workpiece W.

As shown in FIG. 2, when the work W is drilled, a mold fixing means 7 having a cavity corresponding to the shape of the work for fixing the work W is fixed by the mold fixing means 7. In order to form the through holes 12a and 13a in the boss portions 12 and 13, the piercing is performed by a manufacturing tool 1 including a piercing tool 2 as a punching tool for performing piercing as punching.

As shown in FIG. 3, a piercing tool 2 of a manufacturing tool 1 includes a piercing punch (drilling punch) 3 having a cutting edge formed at the tip of a cylindrical body, and a mounting base formed at one end of the piercing punch 3. End 5 and a piercing punch 3
A flank 4 is formed on the side of the cutting edge. And the piercing tool 2 is configured to be operated by pressing drive means such as a cylinder. Here, piercing punch 3
Is provided with a base cylindrical portion 3a as a finishing punch formed with a step between the mounting base end portion 5 and a cutting edge formed at the position of the step between the base cylindrical portion 3a and the piercing punch 3. A flank 6 for finishing is formed on the cutting edge.

The flank surfaces 4 and 6 of the piercing punch 3 are for reducing frictional resistance when piercing is performed. In FIG. 3, they are inclined toward the outer and inner diameter sides of the piercing punch 3. Is formed. The flank faces 4 and 6 need only be formed at least on the outer side, and the inner diameter side may be configured to have the same diameter as the inner diameter of the piercing punch 3 without providing an inclined surface. . In addition, the inclination angles of the flank surfaces 4 and 6 are formed in the range of 1 degree to 5 degrees, and here, they are formed to be 3 degrees. If the inclination angles of the flank surfaces 4 and 6 are smaller than 1 degree, no flank can be obtained and frictional resistance increases, which is inconvenient. On the other hand, if it is larger than 5 degrees, the escape distance becomes short, and the punch strength becomes weak, which is inconvenient.

Further, in FIG. 4, the piercing tool 2 is described as having a configuration in which a base tube portion 3a as a finishing punch is formed. However, without providing the base tube portion 3a, the same diameter except for the flank surface 4 is used. The piercing punch 3 may be configured as follows.

As shown in FIGS. 2 and 3, the die-shaped fixing means 7 is provided with a machining hole 8 through which the piercing tool 2 can move forward and backward. The parts 12 and 13 have a concentricity. As can be seen from FIGS. 3A and 3B, the machining hole 8 is configured to be divided by the upper and lower dies 7A and 7B and to form a circular groove by joining semicircular grooves in cross section. I have. The mold fixing means 7 has a shape that can be fixed along the work W from at least the half of the connecting portion 10, which is a half portion from the center to the bosses 12 and 13. FIG. 2 illustrates a configuration in which the workpiece is fixed along the entire shape of the workpiece. As shown in FIG. 3, the mold fixing means 7 has a half-shaped upper die 7A and a lower die 7B on the left and right sides of the work W arranged at the center thereof. The work W is fixed so as to sufficiently resist the impact of the work W on piercing so as not to deform the work W such as distortion.

When boring the boss portions 12 and 13 of the work W, as shown in FIG. 6, a solid punch 22 which is another form of a piercing tool may be used. In this case, the punch portion 23 is formed in a cylindrical shape,
A flank 24 is provided at the distal end, and a mounting proximal end 25 is provided at the proximal end.

The cylindrical piercing tool 2 and the columnar solid punch 22 are selectively used here when the hole diameter is small and not more than 20 φ (mm). In this case, even with the solid punch 22, drilling can be appropriately performed. If the hole diameter exceeds 20φ (mm), use a cylindrical piercing tool 2
You are using It should be noted that punching can be performed with good processing accuracy up to a hole depth of 50 mm for both the piercing tool 2 and the solid punch 22.

Next, a flow of a series of manufacturing steps will be described with reference to FIG. First, in step S1, a lump of aluminum alloy is formed into a bar-shaped piece having a predetermined size (made corresponding to a shape such as a plate-shaped piece). Then, in step S2, the rod-shaped piece is heated to a temperature at which it can be processed by passing through the heating furnace for a predetermined time. Next, if necessary, in step S3, the rod-shaped piece is taken out of the heating furnace, roll forged, processed into a necessary portion of the bar-shaped piece so as to approximate a final shape, and heated again by the heating furnace. The process may proceed from step S2 to step S4 without performing step S3. In step S4, the heated rod-shaped piece is taken out and press-formed stepwise by a press device, for example, as shown in FIG.
Forging into the shape of the suspension arm as shown in (1).

Next, the forged suspension arm is fixed by the mold fixing means 7 (see FIG. 2) in step S5. Then, the piercing tools 2 and 22 shown in FIGS.
Is punched out to form a through hole. At this time, unlike the drilling, a large amount of lubricating oil is not used in the processed portion, and the lubricating oil is only applied to the pierce punch 3 side with a brush. Further, since the punched chips are cylindrical bulks, they can be easily collected.
The punched cylindrical chips are pushed out from the positions of the bosses 12 and 13 to the tip end of the processing hole 8 in FIG. Further, even if chips are fitted into the cylinder of the piercing punch 3, they can be easily taken out by a tool. Of course, a configuration in which a long hole groove for chip removal is formed in the piercing punch 3 in advance may be adopted.

[0030]

EXAMPLES Examples of a method for manufacturing a forged part for an aluminum alloy automobile will be described below. Note that the present invention is not limited to this embodiment. Piercing tool (Fig. 4
) Is made of SKD61 quenched and tempered material and used as a piercing punch.
φ (mm), outer diameter dimension (outer diameter of flank) 28φ (mm)
To a length of 45 mm, and 3 mm on the outer diameter side at the position of 5 mm at the tip.
A flank inclined at an angle was formed.

The outer diameter (outer diameter of the flank) of a continuous base end cylindrical portion having a step outside the piercing punch is 30φ.
(Mm) and the inner diameter is 25φ (mm).
Then, at the position where the piercing punch and the base end tube part are connected, 3
The flank face was formed with a length of 5 mm, and the base cylindrical portion was formed as a finishing punch. The mounting base end portion that is continuous with the base end tube portion is formed to have a diameter of 110φ (mm) and a length of 40 mm, and has an inner diameter that is continuous with the inner diameter of the base end tube portion. The piercing tool is used by being attached to a pressing drive means such as a cylinder device.

The mold-shaped fixing means (see FIG. 2) uses a state in which the whole work is fixed along the shape of the work from the left and right (front and rear or up and down). The waste mold used in (1) was diverted and processed to provide mold-shaped fixing means.

As the shape of the work, the suspension arm shown in FIG. 1 was used in a forged (AS FORGED) F state (as-forged state). Then, a punching process was performed on the boss portion of the suspension arm by the piercing tool and the mold fixing means described above.

Drilling conditions during processing are φ30 ×
A 35 mm hole was formed. The press load at this time is 150
Performed at kN. The through hole in the boss could be precisely and neatly drilled without distorting the surrounding parts. As for the chips discharged during the drilling, a columnar bulk was discharged.

Also, when hot (350 ° C.), φ30 × 35 m
When m holes are formed, the press load at the time of drilling is 70
Similarly, in the case of kN, the through hole of the boss portion could be precisely and finely drilled without distorting the surrounding portion.

[0036]

As described above, the present invention has the following advantages. (1) In the method of manufacturing a forged part for an aluminum alloy automobile, the through-hole of the boss portion is fixed by a mold-shaped fixing means and is performed by a punching tool such as a piercing tool. Can perform the punching process quickly. Further, since the fixing is performed in a state where the forged part for an aluminum alloy automobile is fixed by the mold-shaped fixing means, there is no adverse effect of generating a distortion or the like at a portion other than the portion where the drilling is performed.

(2) In the method of manufacturing a forged part for an aluminum alloy automobile, a through hole of the boss portion can be formed by punching such as piercing. Therefore, the chips generated to form the through holes become columnar bulks, and have excellent recyclability. Also,
Since the chips are cylindrical bulk, there is no danger of ignition, unlike fine chips by drilling.

(3) Since the manufacturing tool used in the method of manufacturing a forged part for an aluminum alloy automobile uses a die-shaped fixing means and a punching tool such as a cylindrical piercing tool, the diameter is large and the thickness is large. It is possible to precisely and easily perform a punching process on a processed portion of meat.

(4) Since the manufacturing tool used in the method for manufacturing an aluminum alloy forged part for an automobile has a configuration in which a finishing punch is provided at an intermediate position of a drilling punch tool,
By performing a series of operations for punching holes in the boss, finishing can be performed simultaneously, which is convenient.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) are a side view and a front view showing an example of an aluminum alloy forged part for an automobile according to the present invention.

FIG. 2 is a plan view showing a tool for manufacturing an aluminum alloy forged part for an automobile according to the present invention.

3 (a) and 3 (b) are cross-sectional views showing a main part of a mold fixing means for fixing a forged part for an aluminum alloy automobile according to the present invention.

FIGS. 4A and 4B are a side view and an enlarged partial cross-sectional view of a main part showing a punching tool for punching a forged part for an aluminum alloy automobile according to the present invention.

FIG. 5 is a block diagram showing a manufacturing process of the aluminum alloy forged part for an automobile according to the present invention.

FIG. 6 is a partially cutaway side view showing another configuration of the punching tool according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Manufacturing tool 2 Piercing tool (Hole punching tool) 3 Piercing punch (Hole punch) 3a Base cylinder part (finishing punch) 4 Flank 5 Mounting base end 5 6 Flank (finishing) 7 Mold fixing means 7A Upper die 7B Lower die 8 Machining hole 10 Connecting part 11, 12, 13 Boss part 11a, 12a, 13a Through hole W Work

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshiya Inagaki 1100 Higashiyama, Umedo, Oyasu-cho, Oyasu-cho, Mie Prefecture 3D001 AA00 DA04 DA05 4E048 KB01 KB06 4E087 AA08 AA10 BA04 BA12 CA11 CA41 CB01 DA05 DB05 DB15 DB22 DB23 DB24 HA27

Claims (3)

[Claims] 1. A forged part for an aluminum alloy automobile, comprising: a plurality of bosses for engaging with a mating member; and a connecting portion connected to the bosses, wherein directions of through holes of the bosses are different. A manufacturing method, comprising: a first step of forging an aluminum alloy lump formed into a predetermined size into a forged part for an aluminum alloy vehicle having a predetermined shape by a press device; and A second step of fixing the forged part by the mold-shaped fixing means; and a third step of forming a through hole by punching and punching using a punching punch tool on the boss portion of the fixed aluminum alloy forged part for an automobile. A method for producing an aluminum alloy forged part for an automobile, comprising the steps of: 2. The punching tool according to claim 1, further comprising a cutting edge provided on a distal end side of the cylindrical body, and a mounting base end provided on a rear end side of the cylindrical body. A tool for manufacturing a forged part for an aluminum alloy automobile, wherein a flank is formed. 3. The punching tool according to claim 1, further comprising: a cutting edge having a flank on a distal end side of the cylindrical body, and a mounting base end provided on a rear end side of the cylindrical body. Aluminum, wherein a step having a different diameter is formed at an intermediate position of the cylindrical body, a cutting edge of a finishing punch having a diameter larger than the diameter of the tip side is provided, and a flank is formed on the cutting edge of the finishing punch. Tool for manufacturing forged parts for alloy cars.