JPH07124680A - Forged parts and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable the completion of piercing work with a high precision by pressing a piercing punch into a hole-forming part to execute the piercing formation, expanding the forming part and corresponding to a gap vol. CONSTITUTION:At the time of hot-forging a material, after hot-forging so that the shape of the hole-forming part forms to small by the vol. of the hole 11b in the hole forming part scheduled to work, a burr removal work is executed to manufacture a preform for parts. In the condition of holding the preform for parts to high temp. having the transformation temp. or higher, the preform for parts is held while insert-pressing by a split dies 6 composed of the upper and the lower dies forming gaps 4a, 5a having the same size as the finish shape of the hole-forming part. The piercing punch 8 is pressed into the hole-forming part scheduled to work to form the hole 11b and also, the hole-forming part is expanded and corresponds to the vol. of gaps 4a, 5a. In such a way, the hole and the hole-forming part is forged to the desired size by the hot-forging. By this method, the strength of the forged parts 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 forged part and a method for manufacturing the same, and in particular, a hole forming portion and the hole required at a high temperature immediately after hot forming of a material are processed by hot forging,
By eliminating the need for primary processing of holes with tools such as drills, we have reduced machining costs and material costs, and have forged parts that have less metal structure cutting and high strength. The present invention relates to a component and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, so-called core forging is known in which a drilling process is performed in a forging process. However, the conventional forging technique of this kind is used only for parts having a relatively simple shape. As shown in Fig. 15, in the case of a part having a high degree of irregularity with a particularly complicated shape, that is, a special irregular-shaped component, the drilling is performed by using a tool such as a drill 2 after the machining of the component material 1 by forging is completed. Machining was performed on the forming portion 1a.

For example, in the process of forming the kingpin hole 1b of the component material 1 as a knuckle for a medium-sized vehicle, no forging is performed in forging, and the drill 2 is used after the production of the component material 1 is completed by forging. A step of completing a part by performing a drilling process, and then performing a semifinishing drilling process and a finishing drilling process has been adopted.

However, in the method of performing such hole machining by means of machining, first, machining cost is excessive, and moreover, the material is wasted by the volume of the hole 1b generated by the drilling, and furthermore, the metal particles are bent by forging. Since the metal structure that has been kept continuous is cut by machining, there is a drawback that the strength of the forged part is reduced.

Therefore, even in such specially deformed parts, it is desired that the hole forming portion 1a is formed by forging. However, this has not been possible in the past when the bag hole is first formed by forging. Is due to the following reasons.

(1) Since the part material 1 is formed by hot forging, the volume changes due to variations in the thickness of each part and wear of the mold. When the volume of the material part 1 is large, the punching punch has a predetermined hole 1b. There is a problem that the molding is completed without entering the position, and the hole 1b does not become a through hole even if the surface is machined after the machined surface 1c of the finished product.

(2) In order to completely fill the material in the mold when the punch for punching is pushed and to reduce the inclination of the hole 1b to be formed, the shape of the component material 1 is the material when the punch is pushed. However, it is difficult to establish this technique. However, it is necessary to make the punch behave radially so as not to apply a force in an abnormal direction to the punch, that is, to make bending stress applied to the punch as small as possible.

(3) Even if the shape of the component material 1 is set to the above (2), since the temperature of each part of the component material 1 is not uniform, the deformation resistance varies depending on the part, and the punch has a considerable bending stress. Since it occurs, it was difficult to prevent this.

Next, when forming a through hole by forging,
The reason is as follows. (4) Since it is not a blind hole, the material is pulled when the punch is pushed in, and a wall thickness is generated in the inner diameter corner portion 1d on the punch pushing side.

(5) When the hole forming portion 1a of the component material 1 is bifurcated like a knuckle and the hole forming portions 1a are close to each other, the strength of the die (drawing blade) is increased. If it is attempted to sufficiently secure it, the drainage hole of the hole 1b becomes smaller than the thickness of the two pieces of the residue, and the residue cannot be discharged.

Further, Japanese Patent Publication No. 52-33592 discloses a forging method for a T-joint, Japanese Unexamined Patent Publication No. 63-63546 discloses a method for manufacturing a hollow object, and Japanese Utility Model Publication No. 61-143727 discloses a crankshaft having a hole drilling mechanism. A forging device, a back pressure applying punching device in the actual open flat 1-110035, a forging device in the actual open flat 2-65440, and a knuckle forming device in the actual open flat 3-85145 are disclosed, respectively. The object to be machined in the example is not a specially deformed part as in the invention of the present application, or a knuckle which is a specially deformed part is different in the method of forging a hole and has a different configuration from the invention of the present application.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in order to eliminate the above-mentioned drawbacks of the prior art. The purpose of the present invention is to heat a material above its transformation point to perform hot forging. When performing, after hot forging so that the shape of the hole forming portion becomes smaller by the volume of the hole of the hole forming portion to be machined later, deburring processing is performed to produce a component material,
A hole forming part where a parting material is clamped and held by a split mold in which a void having the same size as the finished shape of the hole forming part is formed while holding the part material at a high temperature above the transformation point, and a punching punch is planned to be processed. To form a hole and expand the hole forming part to match the volume of the void, and by forging the hole and the hole forming part to a desired dimension by hot forging, the hole forming part of the hot forging process This is to make it possible to complete the drilling with sufficient accuracy. This also eliminates the need for machining with a drill for drilling to reduce the machining cost and is wasted for drilling. It is to improve the strength of the forged part by reducing the material cost and eliminating the cutting of metal particles associated with the drilling process.

Another object is to heat the material above its transformation point and perform hot forging so that the shape of the hole forming portion becomes smaller by the volume of the hole forming portion to be machined later. After performing forging between parts, deburring is performed to manufacture a part material, and while maintaining the part material at a temperature higher than the transformation point, a void of the same size as the finished shape of the hole forming part is formed in each mold. The split mold holds the component material under pressure, presses the hole punch into the hole forming part to be machined, forms a bag hole leaving a slight residual thickness so that the hole does not penetrate, and expands the hole forming part. To match the volume of the void and forge the hole and forming part to the desired dimensions by hot forging,
Eliminates waste of material associated with drilling, and even parts with a bifurcated shape in which the hole forming parts are close to each other, such as a vehicle knuckle, are later made into through-holes by chamfering to the reference machining surface. Is to be able to
In addition, this makes it possible to perform the drilling of the hole forming portion without difficulty in the forging process.

Still another object is to heat the material above its transformation point to carry out hot forging and then deburring to produce a component material, which is held at a high temperature above the transformation point. As it is, a split mold in which a void of the same size as the finished shape of the hole forming part is formed is used to hold the component material under pressure, and the hole punch is pushed into the hole forming part to be machined to form a through hole, By forging the hole and the hole forming portion to a desired size by forging, it is possible to easily form the through hole in the hole forming portion of the component material only by the forging process, and by this, the through hole forming later Therefore, it is necessary to reduce the number of machining steps and the cost of parts by eliminating the need for face-cutting.

[0015]

SUMMARY OF THE INVENTION In summary, the method for manufacturing a forged part according to the present invention (Claim 1) involves heating a material above its transformation point to carry out hot forging, thereby forming a hole forming part to be machined later. Hot forging is performed so that the shape of the hole forming portion is reduced by the volume of the hole, and then deburring is performed to produce a part material, and the part material is held at a temperature higher than the transformation point. The component material is clamped and held by a split mold in which a void having the same size as the finished shape of the hole forming part is formed, and the hole punch is pushed into the hole forming part to be processed to form the hole and the hole. The forming portion is expanded to match the volume of the void, and the hole and the hole forming portion are forged to a desired size by hot forging.

A forged part according to the present invention (claim 2)
Means that when hot forging is performed by heating the material above its transformation point, hot forging is performed after the hot forging is performed so that the shape of the hole forming portion becomes smaller by the volume of the hole forming portion to be machined later. Punching is performed to produce a component material, and the component material is held by a split mold in which a void having the same size as the finished shape of the hole forming portion is formed while holding the component material at a temperature higher than the transformation point. Hold the clamping pressure and press the punching punch into the hole forming part to be processed to form the hole, expand the hole forming part to match the volume of the void, and form the hole and the hole by hot forging. It is characterized by being obtained by forging a part to a desired size.

Further, in the method for manufacturing a forged part according to the present invention (claim 3), when hot forging is performed by heating the material above its transformation point, only the volume of the hole of the hole forming portion to be machined later is calculated. Hot forging is performed so that the shape of the hole forming part becomes smaller, and then deburring is performed to produce a part material, and the finished shape of the hole forming part while holding the part material at a temperature higher than the transformation point. While holding the component material with a split mold in which a void of the same size as that is formed, press the punching punch into the hole forming part to be processed and leave a slight residual thickness so that the hole does not penetrate. A bag hole is formed, the hole forming portion is expanded to match the volume of the void, and the hole and the forming portion are forged to a desired size by hot forging.

A forged part according to the present invention (claim 4)
Means that when hot forging is performed by heating the material above its transformation point, hot forging is performed after the hot forging is performed so that the shape of the hole forming portion becomes smaller by the volume of the hole forming portion to be machined later. Punching is performed to produce a component material, and the component material is held by a split mold in which a void having the same size as the finished shape of the hole forming portion is formed while holding the component material at a temperature higher than the transformation point. Hold the clamping pressure and press the punching punch into the hole forming part to be machined to form a bag hole leaving a little residual meat so that the hole does not penetrate and expand the hole forming part to expand the volume of the void. And the hole and the forming portion are forged to a desired size by hot forging.

In the method for manufacturing a forged part according to the present invention (claim 5), the material is heated to a temperature above its transformation point to carry out hot forging, and then deburring is carried out to produce a part material,
While holding the part material at a high temperature above the transformation point, hold the part material with a split mold in which a void of the same size as the finished shape of the hole forming part is formed, hold the part material, and plan the punching punch. The hole forming portion is pressed into the hole forming portion to form a through hole, and the hole and the hole forming portion are forged to have a desired dimension by hot forging.

A forged part according to the present invention (claim 6)
Is produced by heating the material above its transformation point to perform hot forging and then deburring to produce a part material, and while maintaining the part material at a high temperature above the transformation point, the hole forming part The component material is clamped and held by a split mold in which a void having the same size as the finished shape is formed, and a hole punch is pushed into the hole forming portion to be machined to form a through hole, and hot forging is performed to It is characterized in that it is obtained by forging the hole and the hole forming portion to desired dimensions.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings. First, a first embodiment of the manufacturing method of the present invention shown in FIGS. 1 to 7 will be described. A material 3 made of a round bar as shown in FIG. 1 (a) (the material is, for example, a knuckle for a medium-sized vehicle, nickel. (Chromium-boron steel is used) is heated to a temperature equal to or higher than the transformation point, that is, 1000 ° C. to 1200 ° C., and die-forged as shown in (b).

Then, when the material 3 is heated above the transformation point temperature and hot forged, the hole forming portion 11a is to be machined by the volume of the hole 11b (FIGS. 5 to 7) of the hole forming portion 11a to be machined later. Hot forging to reduce the shape of
The original shape of the part material 11 is completed.

The part material 11 for which hot forging has been completed is shown in FIG.
As shown in (b) of FIG. 11, since the burr 11d remains around it, the burr is removed as shown in (c), and the component material 11 is manufactured.

Then, as shown in FIGS. 3 and 4, each part, that is, the upper mold 4 and the lower mold 5, has the same size as the finished shape of the hole forming portion 11a while holding the component material 11 at a high temperature above the transformation point. The component material 11 is clamped and held by the split mold 6 in which the gaps 4a and 5a are formed, respectively, and subsequently, as shown in FIG.
To form the hole 11b and the hole forming portion 11a.
Is expanded to match the total volume of the voids 4a and 5a, and the hole 11b and the hole forming portion 11a are forged to a desired size by hot forging.

As shown in FIG. 3, in the cavity 4a of the upper mold 4, the hole 11 of the component material 11 is formed on the wall surface closer to the center.
A semi-circular cavity 4b is formed to accommodate a thin residual wall 11f for preventing b from penetrating, and a semi-circular cavity 5b symmetrical to the semi-circular cavity 5b is also formed in the same portion of the lower die 5 facing the same. By combining these, the split mold 6 forms a washer-like void 6a.

When the upper die 4 and the lower die 5 are combined to form the split die 6, small donut-shaped voids 6b are formed around the punching punches 8 over a certain length outside the voids 4a, 5a. Is formed, and even if the volume of the hole forming portion 11a of the component material 11 varies due to the gap, the tip 8a of the punching punch 8 is processed by a later machining process 11c by absorbing the residual meat 11g in the gap 6b. It is considered to be able to move beyond the end of a given stroke.

This is because if the tip 8a of the punching punch 8 cannot move to a position beyond the machining surface 11c and stops halfway, the depth of the hole 11b formed by forging becomes insufficient, and This is because the hole 11b cannot be a through hole when the machined surface 11c is machined.

The length L of the guide portion 5c slidably supporting the punching punch 8 outside the gaps 4a, 5a of the upper die 4 and the lower die 5 is 1.2 times the diameter of the punching punch 8 or more. It is set to length. This is because a considerable bending stress is generated in the punching punch 8, and it is necessary to support the punching punch with a sufficiently long fitting length.

A knock pin 5e is planted on the upper surface 5d of the lower die 5, and the knock pin is fitted into a knock hole (not shown) of the lower surface 4c of the upper die 5 to align the upper die 4 and the lower die 5. It is configured to be able to.

The upper die 4 and the lower die 5 are hydraulically operated to 20 to
The punching punch 8 is held by a force of n to 600 tons, and the punching punch 8 is 40 tons using a hydraulic cylinder (not shown), a toggle mechanism (not shown) or a wedge mechanism (not shown).
To 80 tons of force.

[0031]

Example 1 Upper mold 4 and lower mold 5 configured as described above
Thus, as shown in FIGS. 3 and 4, as an example of the component material 11, a knuckle (material: manganese, chromium, boron steel) for a medium-sized vehicle is maintained at a high temperature of 1176 ° C. 1
When the punching punches 8 are pressed by the force of 60 ton from the left and right as shown in FIG. 5, the punching punches 8 are pushed into the right and left smoothly, respectively, and the machined surface 11c The hole forming portion 11a of the component material 11 expands at this time to expand into the voids 4a, 5
While being filled in a and forged to a desired size, the residual meat 11f was filled in the void 6a and the residual meat 11g was filled in the void 6b.

At this time, that is, when the pushing of the punching punch 8 is completed, the temperature of the component material 11 is 600 ° C., the pushing time is 1 minute 45 seconds, and the required stroke of the punching punch is 17.
It was 8.4 mm. The hole 11b is not a through hole but a blind hole, and the forged component 1 as shown in FIGS.
I got 2.

[0033]

[Embodiment 2] A knuckle for a medium-sized vehicle (material: manganese.
(Chromium / Boron steel) is maintained at a high temperature of 1071 ° C while holding it with a force of 50 tons from above and below, and as shown in Fig. 5, the punching punches 8 are pushed in from the left and right with a force of 60 tons. The punches 8 are smoothly pushed right and left respectively, and the tip 8a advances beyond the machined surface 11c. At this time, the hole forming portion 11a of the component material 11 is expanded and filled in the voids 4a and 5a and forged to a desired size. At the same time, the residual meat 11f was filled in the void 6a and the residual meat 11g was filled in the void 6b.

At this time, that is, when the pushing of the punching punch 8 is completed, the temperature of the component material 11 is 860 ° C., the pushing time is 1 minute 30 seconds, and the punching stroke is 17 strokes.
It was 8.4 mm. The hole 11b is not a through hole but a blind hole, and the forged component 1 as shown in FIGS.
I got 2.

The forging process is performed by the forging component 1 shown in FIG.
This is completed by obtaining 2. However, the remaining meat 11g is removed by machining later, and the remaining meat 11f is removed by cutting to the machined surface 11c shown by the one-dot chain line in FIG. 6 so that the hole 11b becomes a through hole. , The through hole is not required to be drilled, the material conventionally scraped by the through hole is not wasted, and the hole forming portion 11b is expanded and formed by the amount of the through hole. Since the continuous state of the particles is not cut, the mechanical strength is improved.

Next, the second embodiment of the present invention shown in FIGS.
Examples will be described. The manufacturing process of the component material 21 is the same as that of the first embodiment shown in FIG. 1, but the size of the hole forming portion 21a is set to a desired size as the finished product, and expansion is performed in advance as in the first embodiment. The difference is that it is not kept small.

Assuming the above difference from the first embodiment, first, as shown in FIG. 1, the material 3 is heated above its transformation point to carry out hot forging, and then deburring is carried out to carry out component material. As shown in FIG. 8 to FIG. 11, the finished shape of the hole forming portion 21a is formed in each mold, that is, the upper mold 14 and the lower mold 15, while holding the component material 21 at a high temperature equal to or higher than the transformation point. The component material 21 is clamped and held by the split mold 16 in which the voids 14a and 15a of the same size are formed, and the punching punch 18 is pushed into the hole forming portion 21a to be processed to form the through hole 21b, and the hot work is performed. The hole 21b is forged to a desired size by forging.

Voids 14a, 15 of the upper mold 14 and the lower mold 15
The length L of the guide portion 15c that slidably supports the punching punch 18 outside a is set to be 1.2 times or more the diameter of the punching punch 18. This is because a considerable bending stress is generated in the punch punch 18, and it is necessary to support the punch punch with a sufficiently long fitting length.

Further, conical projections 18b are formed at the center of the tip 18a of the punching punch 18, and when the punching punch 18 is pushed into the hole forming portion 21a of the component blank 21, the projection 18b is first formed into the component. The material 21 is configured to be pierced.

Further, the depression corners 14b, 15b on the pushing side of the punching punch 18 of the upper mold 14 and the lower mold 15.
Has a large chamfer. This is a method of forming the through hole by forging at once in the second embodiment without forming the blind hole as in the first embodiment.
This is for preventing the material from being pulled by pushing 8 into the hole forming portion 21a and causing a lack of thickness at the inner diameter corner portion 21d of the hole 21b of the hole forming portion 21a on the pushing side of the punching punch 18.

That is, when the punching punch 18 is pushed into the part material 21 hole forming portion 21a, the material is the upper mold 14 and the lower mold 15.
First, it behaves in the space between the impression corners 14b, 15b and the periphery of the projection 8b of the punching punch 18,
This is to prevent excess thickness from being formed in the inner diameter corner portion 21d of the hole 21b on the punching punch pressing side of the component material 21 and this portion.

By forming a conical projection 18b at the tip 18a of the punch punch 18, the punch punch 1 is formed.
The force in the pushing direction of 8 is distributed in the lateral direction, the friction resistance between the material and the mold surface is increased, and the pulling of the material is reduced, so that the inner wall corner portion 21d can be prevented from being thinned. There is.

In the lower center of the upper mold 14, a countersink 14c having a circular horizontal cross section is formed for temporarily letting the material scraps 21e of the punching punch 18 upward, and in the lower mold 15, the countersink 14c is formed. A through hole 15f having the same diameter as the above is formed so as to open on the lower surface 15d.

Then, the scraps 2 by the punching punch 18
Since 1e is initially larger than the diameter of the shaving hole 15f, it cannot be freely dropped downward, but since the pair of punching punches 18 are extruded from both sides, they are crushed and thinned by these, and the shaving hole 1e is removed. It is possible to drop from 15f.

A knock pin 15 is provided on the upper surface 15g of the lower mold 15.
e is planted, and the knock pin is configured to fit into a knock hole (not shown) of the lower surface 14e of the upper mold 14 so that the upper mold 14 and the lower mold 15 can be aligned with each other.

The upper mold 14 and the lower mold 15 are hydraulically operated to 20
The punching punch 18 is held by a force of 600 ton from ton, and the punching punch 18 uses a hydraulic cylinder (not shown), a toggle mechanism (not shown), or a wedge mechanism (not shown) for 40 t.
It is configured to be pushed in with a force of 80 ton from on.

[0047]

[Third Embodiment] As shown in FIGS. 8 to 10, the component material 2 is formed by the upper mold 14 and the lower mold 15 configured as described above.
As one example, a knuckle for a medium-sized vehicle (material: manganese, chromium, boron steel) is held at a high temperature of 1090 ° C. and clamped from above and below by a force of 100 ton,
As shown in FIG.
When I pushed it in with the force of ton, first punch 18
The conical projection 18b of the tip 18a of the blade bites into the hole forming portion 21a of the component material 21 so that the material behaves in the radial direction, and the impression corner portions 14b, 1 of the upper mold 14 and the lower mold 15 are
5b and the hole punching punching portion of the component material 21 have extra thickness, and the periphery of the entrance of the hole 21b has a slightly expanded shape, and it is possible to prevent lack of thickness.

Furthermore, since the projection 18b pierces the component material 21, the force in the pushing direction of the punching punch 18 is distributed laterally, increasing the frictional resistance between the material and the die surface, and pushing the punching punch 18 in There was no material pulling accompanying, and this also prevented the wall thickness around the entrance of the hole 21b.

Further, when the punching punch 18 penetrates the hole forming portion 21a of the component material 21, a pair of the scraps 21e are pushed out from the hole 21b. These are, as shown in FIG. When they approached each other, they were flattened and flattened, and the thickness of the two sheets became thinner than the diameter of the lees-draining hole 15f, and they dropped and could be easily discharged.

At this time, that is, when the pushing of the punching punch 18 is completed, the temperature of the component material 21 is 584 ° C., the pushing time is 1 minute 33 seconds, and the required stroke of the punching punch is 18.
It was 5.0 mm. Then, the hole 21b became a through hole, and the forged component 22 as shown in FIGS. 12 and 13 could be obtained.

[0051]

[Embodiment 4] A knuckle for a medium-sized vehicle (material: manganese
(Chromium / Boron steel) is maintained at a high temperature of 1150 ° C. and is clamped from above and below by a force of 50 tons, and as shown in FIG.
When pushed with the force of, the punching punches 18 are smoothly pushed to the left and right respectively, and the holes 21b are formed in the same manner as in the third embodiment.
The hole 21b becomes a through hole without forming a wall thickness around the entrance of the forged part 2 as shown in FIG. 12 and FIG.
I got 2.

At this time, that is, when the pushing of the punching punch 18 was completed, the temperature of the component material 21 was 568 ° C., the required pushing time was 1 minute 48 seconds, and the required stroke of the punching punch 18 was 185.0 mm.

Although the forging process is completed by obtaining the forged component 22 shown in FIG. 13, it is only necessary to machine the machined surface 21c shown by the alternate long and short dash line in FIG. 6 to perform the drilling of the hole 21b. It becomes unnecessary.

The present invention is configured as described above,
The operation will be described below. In the first embodiment, the volume of the hole forming portion 11a of the component material 11 is set to the hole 11b.
Is formed by forging by forming a small volume corresponding to the volume when it is extruded, and then the punching punch 8 is pushed in to form the hole 11b.
Since the hole forming portion 11a is expanded and the hole forming portion 11a is expanded to a desired size, there is very little waste of material and the continuous state of the metal particles is not cut.
The mechanical strength of can be improved.

Further, since the space 6b for absorbing the residual meat 11g is provided between the periphery of the punching punch 8 and the upper die 4 and the lower die 5, even if the volume of the hole forming portion 11a varies to some extent. This is absorbed by the remaining meat 11g entering this space, and a sufficiently clean forged part 12 can be obtained.

In the second embodiment, the punching punch 18 is used.
Forming a conical projection 18b at the center of the tip 18a of
In addition, the impression corners 14 of the upper mold 14 and the lower mold 15
Since a and 15a are each slightly chamfered, a surplus is formed around the entrance of the hole 21b when the punching punch 18 is pushed, so that it is possible to prevent the occurrence of lack of thickness in this portion. A sufficiently clean through hole can be formed.

Further, the conical projection 18b causes the material to move in the lateral direction as the punching punch 18 is pushed, so that the friction between the split mold 16 and the material is increased and the material is not pulled. It is possible to prevent flesh thickness around the entrance of the hole 21b.

Further, the hole 2 as a through hole at a stretch by forging
1b can be formed, and there is no need to remove the residual meat by machining, which can be rationalized.

[0059]

As described above, according to the present invention, when the material is heated above its transformation point and hot forged, the shape of the hole forming portion is reduced by the volume of the hole forming portion to be machined later. Hot forging and then deburring to make a part material, and form a void with the same size as the finished shape of the hole forming part while holding the part material at a temperature higher than the transformation point. By holding the component material with the split mold, the hole punch is pushed into the hole forming part to be processed to form a hole and the hole forming part is expanded to match the volume of the void.
Since the hole and the hole forming part are forged to a desired size by hot forging, there is an effect that the hole forming part can be drilled with sufficient accuracy in the hot forging process, and as a result, the hole forming It is possible to reduce machining costs by eliminating the need for machining with a drill to reduce the material cost wasted for drilling, and to eliminate the cutting of metal particles that accompanies drilling and to forge parts. There is an effect that the strength can be improved.

Further, when hot forging is performed by heating the material above its transformation point, hot forging is performed so that the shape of the hole forming portion becomes smaller by the volume of the hole forming portion to be machined later. Deburring process is performed to produce a part material, and the part material is sandwiched by a split mold in which a void of the same size as the finished shape of the hole forming part is formed while holding the part material at a temperature higher than the transformation point. Hold the pressure, press the punching punch into the hole forming part to be machined, form a bag hole leaving a little meat so that the hole does not penetrate, expand the hole forming part to match the volume of the void, heat Since the hole and the forming part are forged to the desired size by the inter-forging, it is possible to eliminate the waste of material due to the drilling work, and moreover, the hole forming part is close to each other like a vehicle knuckle. Even parts that have been Can be the through hole by performing surface until Kumen cutting machining, also it has the effect that can make it possible to carry out the drilling of the hole forming element in a result reasonably forging process.

Further, the material is heated to a temperature above its transformation point and hot forged, and then deburring is performed to manufacture a component material, and a hole is formed while holding the component material at a temperature higher than the transformation point. The component material is clamped and held by a split mold in which a void of the same size as the finished shape of the part is formed, and the hole punch is pushed into the hole forming part to be processed to form a through hole, and the hole is formed by hot forging. Since the hole forming part and the hole forming part are forged to the desired size, there is an effect that the through hole can be easily formed in the hole forming part of the component material only by the forging process. Since there is no need for machining, there is an effect that the number of machining steps and the cost of parts can be reduced.

[Brief description of drawings]

FIG. 1 to FIG. 7 relate to a first embodiment of the present invention, and FIG. 1 is a perspective view showing a process of manufacturing a part material of a vehicle knuckle from a round bar by hot forging.

FIG. 2 is a perspective view showing a state before the component material is clamped and held by an upper die and a lower die.

FIG. 3 is a vertical cross-sectional view showing a state similar to that of FIG.

FIG. 4 is a vertical cross-sectional view showing a state in which a component material is clamped and held by an upper die and a lower die.

FIG. 5 is a vertical cross-sectional view showing a state in which the hole forming portion of the component material has been drilled by hot forging by the hole punching.

FIG. 6 is a vertical sectional view of the completed forged part.

FIG. 7 is a perspective view of the completed forged component.

8 to 13 relate to a second embodiment of the present invention,
FIG. 8 is a perspective view similar to FIG.

FIG. 9 is a vertical sectional view similar to FIG.

FIG. 10 is a vertical sectional view similar to FIG.

11 is a vertical sectional view similar to FIG.

12 is a vertical sectional view similar to FIG.

13 is a perspective view similar to FIG. 7. FIG.

FIG. 14 and FIG. 15 relate to a conventional example, and FIG. 14 is a vertical cross-sectional view showing a state in which a forged component without drilling is drilled with a drill.

FIG. 15 is a perspective view showing a state in which a forged part is drilled.

[Explanation of symbols]

 4 Upper mold 4a Gap 5 Lower mold 5a Gap 6 Split mold 8 Hole punch 11 Part material 11a Hole forming part 11b Hole 12 Forging part 14 Upper mold 14a Gap 15 Lower mold 15a Gap 16 Split mold 18 Hole punch 21 Part material 21a Hole forming Part 21b Hole 22 Forged part

Claims (6)

[Claims] 1. When performing hot forging by heating a material above its transformation point, hot forging is performed so that the shape of the hole forming portion becomes smaller by the volume of the hole forming portion to be machined later. After that, deburring is performed to produce a component material, and the split die in which a void having the same size as the finished shape of the hole forming portion is formed while holding the component material at a temperature higher than the transformation point While holding the component material under pressure, the punching punch is pushed into the hole forming part to be machined to form the hole and the hole forming part is expanded to match the volume of the void, and the hole is formed by hot forging. A method for manufacturing a forged component, which comprises forging the hole forming portion to a desired size. 2. When hot forging is performed by heating a material above its transformation point, hot forging is performed such that the shape of the hole forming portion is reduced by the volume of the hole forming portion to be machined later. After that, deburring is performed to produce a component material, and the split die in which a void having the same size as the finished shape of the hole forming portion is formed while holding the component material at a temperature higher than the transformation point While holding the component material under pressure, the punching punch is pushed into the hole forming part to be machined to form the hole and the hole forming part is expanded to match the volume of the void, and the hole is formed by hot forging. A forged part obtained by forging the hole forming portion to a desired size. 3. When hot forging is performed by heating a material above its transformation point, hot forging is performed so that the shape of the hole forming portion is reduced by the volume of the hole forming portion to be machined later. After that, deburring is performed to produce a component material, and the split die in which a void having the same size as the finished shape of the hole forming portion is formed while holding the component material at a temperature higher than the transformation point The component material is held under pressure, the punching punch is pushed into the hole forming part to be processed, and a bag hole is formed while leaving a slight residual thickness so that the hole does not penetrate, and the hole forming part is expanded to A method for manufacturing a forged component, characterized in that the hole and the forming portion are forged to a desired size by hot forging so as to match the volume of the void. 4. When hot forging is performed by heating a material above its transformation point, hot forging is performed so that the shape of the hole forming portion is reduced by the volume of the hole forming portion to be machined later. After that, deburring is performed to produce a component material, and the split die in which a void having the same size as the finished shape of the hole forming portion is formed while holding the component material at a temperature higher than the transformation point The component material is held under pressure, the punching punch is pushed into the hole forming portion to be machined, a bag hole is formed leaving a slight residual thickness so that the hole does not penetrate, and the hole forming portion is expanded to A forged part obtained by forging the hole and the forming portion to a desired dimension by hot forging, matching the volume of the void. 5. A part material is produced by heating a material to a temperature above its transformation point to perform hot forging, and then performing deburring processing to produce the part material, and holding the part material at a temperature above the transformation point while the hole is maintained. The component material is clamped and held by a split mold in which a void of the same size as the finished shape of the forming part is formed, and a punch is pressed into the hole forming part to be machined to form a through hole, A method for manufacturing a forged component, characterized in that the hole and the hole forming portion are forged to a desired size by forging. 6. A component material is manufactured by heating a material to a temperature above its transformation point to perform hot forging, and then deburring to produce a component material, and holding the component material at a temperature higher than the transformation point while the hole is maintained. The component material is clamped and held by a split mold in which a void of the same size as the finished shape of the forming part is formed, and a punch is pressed into the hole forming part to be machined to form a through hole, A forged component obtained by forging the hole and the hole forming portion to desired dimensions by forging.