JPS63212031A - Method and tool for working precision parts - Google Patents

Abstract

PURPOSE:To reduce manufacturing cost and to improve yield by forming a recessed part for promoting material flow on both end faces of a working stock, then, subjecting to forging by the pressurizing and knockout punch providing the discharging path of a noncompressive medium. CONSTITUTION:In the case of forming a cylindrical outer peripheral face, recessed parts 43a, 43a are formed in advance on both end faces of a working stock 11a by performing forging by using a punch 1C for recessed part forming and a knockout punch 4C prior to the forging. In this case, the recessed part 43a of a working stock 11a on which a truncated conical projecting part 21 is formed at the end part of a head part 20a is easily formed by the punches 1C, 4C. Then, this working stock 12a is subjected to forging by the punches 1, 4 equipped with the discharging paths 44, 45, 51 of a non-compressive medium. Machining is not required at all because of punching being executed after forming the recessed part 43a to reduce the manufacturing cost. Due to the discharging of the medium being smoothed, the generation of flaws is prevented to improve the yield.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to forging materials or equipment components.
A new method for manufacturing solid disk-shaped parts or ring-shaped parts such as spacers, etc., that allows improved contact (t/H) on the cylindrical outer peripheral surface to be easily obtained by upsetting forging. and tools.

(Prior Art) In order to improve the contact (t/H in the figure) of the cylindrical outer peripheral surface 30c of the solid disk-shaped component 30 illustrated in FIG. After processing the volume into a solid disk shape by drilling and forging the cylindrical material,
The cylindrical outer circumferential surface or both axial end surfaces of this processed product are shaped by performing several mechanical processes such as cutting and grinding. This is because the contact (1/■) of the cylindrical outer circumferential surface obtained by forging alone is limited to 0.8 or less, and this is because the ring-shaped part 30 has a central hole penetrated through its center. The same applies in the case of

(Problems to be Solved by the Invention) After forging a material as described above, repeatedly cutting and grinding the cylindrical outer circumferential surface or both axial end faces of the processed product over several processes is It requires time and effort due to the combination of processing contents and the repeated construction of many processing steps,
In the case of mass production processing, this is a major problem in that it inevitably leads to higher costs and lower yields.

(Means for Solving the Problems) In order to solve the above problems, the present invention improves the forging process and improves the contact (t/H) of the cylindrical outer circumferential surface only by the forging process. In addition, it is possible to provide a solid disk-shaped part or a ring-shaped part with improved flatness of both end faces in the axial direction, making it possible to simplify the process and improve the yield. Specifically, A solid disk-shaped workpiece is forged through a die having a hole for forming a predetermined cylindrical outer circumferential surface, and a pressure punch and a knockout punch inserted into the die hole to form a medium having a predetermined cylindrical outer circumferential surface. When obtaining a real disk-shaped part or a ring-shaped part through subsequent central hole penetration, recesses for promoting material flow are formed on both axial end faces of the processed material using a recess-forming punch and a knockout punch. After that, by forging using a pressure punch and a knockout punch, a solid disk-shaped part or a ring-shaped part with improved cylindrical circumferential rotation is obtained, and furthermore, the processing used in the above-mentioned processing is As a tool for forging, a solid disk-shaped workpiece is forged through a die having a hole for forming a predetermined cylindrical outer circumferential surface, and a pressure punch and a knockout punch inserted into the die hole. In order to obtain a solid disk-shaped part with a surface or a ring-shaped part through subsequent central hole penetration, both punches are provided with a discharge path for an incompressible medium such as lubricating oil.

(Function) According to the above-mentioned technical means of the present invention, FIGS.
1 for obtaining a solid disc-shaped part as shown in Figure (III)
As an example, the outer diameter of the second figure.

The cylindrical material 1a with a height Ho is made into a solid disc-shaped workpiece 11a shown in FIG. In a die 2 having a die hole 2a for forming a cylindrical outer circumferential surface, a workpiece 11a is forged prior to being forged through a pressure punch 1 and a knockout punch 4, each of which has a flat head. Using a punch 1c for forming a recess and a knockout punch 4c, each of which has a substantially truncated conical press-fit convex portion 21 on the end surface of each head 20a, as illustrated in FIG. 2, and as shown in FIG. 2 (II), the workpiece 12a is formed with concave portions 43a, 43a at both ends in the axial direction, and a corner portion 42a is a portion not in contact with the tool. This processed material 12a is placed in a die 2 having a hole 2a for forming a predetermined cylindrical outer circumferential surface as shown in FIG. Then, by performing the final forging process using the knockout punch 4, as shown in FIG. Solid disc-shaped part 1 improved to 0.8 or higher
3a can be obtained. That is, in this final forging process, by applying punch pressure, the outward material necessary to completely fill the unfilled gap formed between the corner 42a of the workpiece 12a and the punches 1 and 4 is removed. A flow is generated and an inward material flow flowing into the recess 43a is generated, and due to the generation of this inward material flow, the outward material flow necessary for filling the unfilled portion can be smoothly performed with a low pressing force. As a result, it is possible to improve the contact (t/H) of the cylinder outer peripheral surface, and at the same time, the flatness of both end faces in the axial direction is also improved, as shown in Fig. 4. (1) shows a solid disk-shaped component 30a obtained by the above-described processing method of the present invention. FIG. 4 (II) shows a ring-shaped part 30b produced by the processing method of the present invention, in which a through hole 31b is punched at the center position.
However, in obtaining such a ring-shaped part 30b, as shown in FIGS. 5 to 5(rV) and FIG. 6, the outer diameter Do and height shown in FIG. The point of turning the cylindrical material 1b of size Ho into a solid disk-shaped processed material 11b as shown in FIG.
This is the same as in case I), and then the recesses 43b, 43b are formed on both axial end faces of the processed material 11b using the recess forming punch 1c and the knockout punch 4c, but after this step. Through hole 31b in the center
In order to punch out the material as shown in Figure 4 (2),
In the punches lc and 4c, as illustrated in FIG.
is different from the medium-practical one shown in FIG. 3 earlier, in that a tapered columnar protruding mold surface 21f whose tip is a conical surface is protruded from the center part of the flat mold surface 21e at a height h. By forming the shape so that the recesses 43b, 43b are deeper as shown in FIG. The material 12b is forged, and this processed material 12
b as shown in Figure 5 (I[I), Figure 2 (I[[)
As in the case of , the final forging process is performed using a die 2 having a die hole 2a as a predetermined cylindrical outer circumferential surface, and a pressure punch 1 and a knockout punch 4 whose heads are both flat surfaces. A processed material 13b having a cylindrical outer peripheral surface in which the unfilled corner portions are completely filled is obtained, and the recesses 43b, 43b are transformed into recesses 44b, 4.
A ring-shaped part 14 is left as 4b, and the center of this workpiece 13b is punched to form a through hole 31b.
b, and the part 30b shown in FIG. 4(n)
corresponds to That is, by the processing method of the present invention, a solid disk-shaped part 30a or a ring-shaped part 30b, which has improved contact (1/H) on the cylindrical outer circumferential surface and good flatness of both end faces in the axial direction, is cut, It does not require a grinding process (it can be produced only by a forging process).

In the processing method of the present invention described above, from the workpiece 12a shown in FIG. 2 (11) to the part 13a shown in FIG.
In the forging process to obtain the workpiece 13b shown in FIG. 5(III) from the workpiece 12b shown in FIG. 1 and the knockout punch 4, if an incompressible medium such as lubricating oil is used in conjunction with the lubrication treatment or processing of the workpiece, each recess 43a of the workpiece 12a, 12b,
If there is a possibility that the same medium may be enclosed within 43b, the recesses 43a, 4 due to the progress of forging by both punches 1.4.
3b is closed, the pressure of the medium enclosed in the recess becomes high, and it is discharged through the gap between the flat surfaces of both punches 1.4, so that the pressure of the medium enclosed in the recess increases, and the medium is discharged through the gap between the flat surfaces of both punches 1.4. A flaw 49 is generated on the flat end surface, and this flaw 49 develops and expands as the number of machining increases, which may have an adverse effect on the end surface of the product. Therefore, in the present invention, as illustrated in FIG. By forming a discharge hole 44 along the central axis of the punch 1.4 and a discharge path by a radial discharge groove 45 on the surface that communicates with the workpiece surface and the surface that contacts other tools on the opposite side, the punch shown in FIG. As shown in the usage state, the medium can be smoothly discharged to the outside, and the problem shown in FIG. 7 can be solved. .

(Example) A suitable example of the forging processing means of the present invention and an example of a processing tool used therein will be described below.

Example 1 Hereinafter, the method of the present invention will be described in detail regarding an example of forging a solid disc-shaped component 30a shown in FIG. 4(1).

FIG. 2 shows the processing steps for a disk-shaped part. Processing is carried out in the order of steps (I), (n), and (I[[), and the part 13a obtained in step (III) is , corresponds to the solid disk-shaped component 30a shown in FIG. 4 CI).

First, a cylindrical material 1a to be processed is a disc-shaped part 13.
A cylinder with the same volume as a, its outer diameter Do and height Ho are:
It is desirable to adopt a value of these ratios, Ho/Do, in the range of 1.0 to 1.5.

Step (1) in FIG. 2 is a step of upsetting the cylindrical material 1a to a point close to the outer diameter of the product.

In step (I[) in FIG. 2, the workpiece 11a obtained in step (1) is inserted into a ring-shaped die in which the HD2 inside the die is slightly smaller than the outer diameter of the product, as shown in FIG. Tip shape 2
This is a step of applying pressure using a punch having 0a and a knockout punch. Here, the tip shape shown in FIG. 3 has a diameter d of the tip flat portion 21c. , d o = (0,3 to 0.7) X D 2 .

Angle θ-5° to 20° with respect to the inclined surface 21d.

The boundary 21a shall be appropriately rounded.

The processing in step (II) shall be carried out under a processing surface pressure (the value obtained by dividing the pressing force by the contact area between the end face of the punch or knockout punch and the workpiece) of 200 kg f /dd or less.

The workpiece 12a obtained by the processing in step (II) has a recess 43a formed by the tip shapes of the punch la and the knockout punch 4a, and a surface 4 not in contact with the tool.
2a.

In step (I[I) in FIG. 2, the workpiece 12a obtained in step (II) is inserted into a ring-shaped die with an inner diameter,
This is a step of applying pressure using a punch 1 and a knockout punch 4 having flat tips (see FIG. 9).

In this process, if the punch is pressurized, the workpiece 1
An outward flow of material necessary to fill the unfilled gap formed by the corner 42a of 2a and the tool and an inward flow of material flowing into the recess 43a occur. By generating this inward material flow, the outward material flow necessary for filling the unfilled portion can be generated with a low pressing force, and as a result, it is possible to improve the contact of the outer peripheral surface of the cylinder.

On the other hand, the internal volume of the recess 43a can be changed by selecting the tip shapes of the punch 1a and the knockout punch 4a shown in FIG. It is possible to complete the process, and a disk-shaped component 13a with good flatness on both axial end faces can be obtained.

Example 2 Next, FIG. 5 shows the processing steps for the ring-shaped part 30b, in which processing is performed in the order of step (■), step (■), step (■), and step (IV). The part 14b obtained by the steps (■) corresponds to the ring-shaped part 30b shown in FIG. 4 (11).

First, the cylindrical material 1b to be processed is a ring-shaped part 30.
It is a cylinder whose volume is the volume of b plus the volume of the scraps, and its dimensions and shape are the same as the cylinder material 1a shown in FIG.

Step CI) in FIG. 5 is the same as step (1) in FIG. 2, which is a step of upsetting the cylindrical material 1b to near the outer diameter of the product.

Step (n) in Fig. 5 is the processed material 1 obtained in step (1).
1b is inserted into a ring-shaped die having an inner diameter D2 slightly smaller than the outer diameter of the product, and is pressurized with a punch la and a knockout punch 4a having a tip shape 20b shown in FIG. 6. Here, for the tip shape shown in FIG. 3, the outer diameter d1°d2 of the protrusion 21f is d + = (0,8 to 1.0)Xd, d: Product 1
Inner diameter d2 of 4b = (1,0~1.4) X d Height h of protrusion 21f is h = (0,1~0.5) The portion 21b shall have an appropriate roundness. The processing conditions of step (I[) are the same as those of step (II) shown in FIG.

Fig. 5, Processed material 1 obtained by processing in step (TI)
2b has a recess 43b formed by the tip shapes of the punch la and the knockout punch 4a, and a surface 42b not in contact with the tool.

The workpiece 12b obtained in step (If) in FIG. 5 is processed in the same manner as in step (III) in FIG. 2 using the same mold.

In this case, the deformation process involves the generation of an outward material flow necessary to fill the unfilled gap formed by the corner portion 42b of the workpiece 12b and the tool by pressurizing the punch; An inward flow of material flows into the recess 43b (44b). By generating this inward material flow, the outward material flow necessary for filling the unfilled portion can be generated with a low pressing force, and as a result, it is possible to improve the contact of the outer circumferential surface of the cylinder.

Moreover, the contraction of the inner diameter d3 due to the closure of the recess 43b can be achieved by adjusting the outer diameter d2 of the tip protrusion of the punch 1 and the knockout punch 4 so that it becomes equal to or less than the product inner diameter d.

Subsequently, as shown in step (IV) of FIG. 5, the ring is punched out to have an inner diameter d, thereby obtaining a ring-shaped part 14b.

Note that during punching, the presence of the recess 44b facilitates the escape of material into the interior, resulting in good properties of the sheared surface.

As described above, in the series of processing steps for the disk-shaped component 13a and the ring-shaped component 14b, it is taken into consideration that heat treatment, lubrication treatment, etc. of the processed product between steps are performed as necessary.

By the way, an incompressible medium such as lubricating oil used during the lubrication treatment or machining of the workpiece is in the recess 43a or 43b.
If there is a possibility that the lubricating oil or other medium trapped in the gap becomes high pressure due to the blockage of the recess 43a (43b) as the machining progresses in step (III), Because it is discharged out of the system through the gap between the surfaces of punch 1 and knockout punch 4 used for processing,
A radial flaw 49 shown in FIG. 7 occurs. This flaw 49 develops and expands as the number of processes increases, resulting in an adverse effect on the end surface of the product.

Therefore, as shown in FIG. 8, the punch 1 and the knockout punch 4 have a discharge hole 44 along the central axis and a discharge groove 44 on the surface to be machined that communicates with the hole and on the surface that contacts other tools on the opposite side.
By providing 5, it becomes possible to discharge lubricating oil and the like during machining to the outside of the system. It should be noted that FIG. 8 only shows the features of the present invention, and omits general details necessary for a pressure punch and a knockout punch.

FIG. 9 shows a mold configuration employing the tool shape according to the present invention. The medium such as lubricating oil accumulated in the recess 53 is discharged by pressure through the discharge hole 51 on the punch side, and passes through the discharge hole 44 and the discharge groove 45 connected thereto on the knockout punch side to the gap 6 in the mold. is discharged, and furthermore,
Although not shown in the figure, it is discharged from the inside of the die 2 to the outside through a hole or the like. As a result, filling of the corner unfilled gap 52 of the workpiece 12a and closing of the recess 53 proceed simultaneously.

When performing a series of these processes from wire rods using a multi-stage heading machine, etc., the shape of the cut end surface will not be good, so before the upsetting process shown in Figure 2 and Figure 5 step (1), The process of straightening the end face 40 of the material 1o shown in FIG.
4b is obtained.

Next, specific examples of the present invention will be described.

A carbon steel (JIS 535C equivalent) wire rod for machine structures with an outer diameter of 20 mm was subjected to spheroidization treatment, lubrication treatment, and processing using a multistage heading machine. The material height and cutting length) HO was set to 24 fins, and the end face correction process shown in FIG. 10 was included.

When obtaining a disc-shaped product, in the processing of step (n),
The tip shapes of the punch 1c and the knockout punch 4c in FIG. Processing of [) (D = 30mSH = 1
0 Tsuru) has a machining surface pressure of approximately 180 kg f /i1,
A contact t/H of the outer peripheral surface of the cylinder of 0.9 or more can be achieved.

In conventional closed forging processing, the processing surface pressure is 200 kg.
Even if it is increased to a level of /-, the contact on the outer circumferential surface of the cylinder is 0°8 or less.

On the other hand, when obtaining a ring-shaped product, in the processing of step (II), the tip shapes of the punch lc and knockout punch 4c shown in FIG. 6 are changed to D2-29. hn.

d+-16w, d2-13m, and the protrusion height h was 61 m on the punch side and 3 dragons on the knockout punch side.

At this time, the machining surface pressure was stopped at about 180 kg f/-, and the process (I [[) (7) Machining (D = 30 m, H = 1
2mm), it is possible to achieve a contact of t/H-0.95 or more on the cylindrical outer peripheral surface even with a machining surface pressure of about 160 kg f/-.

Punch 1 used in step (III) during the above processing
The knockout punch 4 has an escape route for lubricating oil, etc., as shown in FIG.
diameter 2B, depth 1B of the discharge groove 45 on the end surface, width 2fi,
The number of grooves was 3 (equally distributed chambers).

(Effects of the Invention) As explained above, according to the forging method of the present invention, in the upsetting process (II), the solid disc-shaped part 3
When obtaining 0a, a recess 43a is provided, and when obtaining a ring-shaped part 30b, a recess 43b is provided, so that the outer circumferential surface of the cylinder can be formed at a low machining surface pressure in the final upsetting process (■). It becomes possible to machine parts with good contact, and it is possible to omit machining steps such as cutting and improve yield.

In addition, when obtaining the solid disk-shaped part 30a,
Depending on the selection of the shape of the recess 43a, it is possible to process parts with good end face flatness.

In addition, when using an incompressible medium such as lubricating oil for the purpose of lubrication, if there is a possibility that the medium such as lubricating oil may be trapped in the recess during processing in the process (DI), By providing small-diameter discharge holes along the central axes of the punch 1 and knockout punch 4 used for processing [l], the pressure of the medium such as lubricating oil existing in the recess can be reduced. It becomes possible to suppress the buildup and discharge it out of the system, making it possible to easily carry out the above-mentioned processing.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the contact of the outer circumferential surface of the cylinder;
The figure shows the process of machining a solid disc-shaped part, and Figure 3 is a cross-section showing the tip shape of the punch and knockout punch used in step (■) when machining a solid disc-shaped part. 4(1) is a cross-sectional view of a solid disk-shaped part, FIG. 4(II) is a cross-sectional view of a ring-shaped part, and FIG. 5 is a diagram showing the processing process of the ring-shaped part. Figure 6 is a cross-sectional view showing the tip shape of the punch and knockout punch used in process (II) when processing ring-shaped parts, and Figure 7 is a conventional sealed forging with high pressure lubrication. Figure 8 shows the shape of a punch or knockout punch with holes for releasing lubricating oil, etc., and Figure 9 shows how the tool shown in Figure 8 is used. FIG. 10 is a diagram showing the construction of the mold in use, and is a drawing of the material in half section. Figure 70 Figure 9

Claims (2)

[Claims] (1) A solid disk-shaped processed material is forged through a die having a hole for forming a predetermined cylindrical outer circumferential surface, a pressure punch and a knockout punch inserted into the die hole, and a predetermined cylindrical outer circumference is formed. In order to obtain a solid disk-shaped part with a surface or a ring-shaped part through the subsequent piercing of the center hole, the material flow is controlled by a recess-forming punch and a knockout punch on both axial end faces of the workpiece. Precision, characterized by forming a promoting recess and then forging through a pressure punch and a knockout punch to obtain a solid disc-shaped part or a ring-shaped part with improved perforation on the cylindrical outer circumferential surface. How to process parts. (2) A solid disk-shaped processed material is forged through a die having a mold hole for forming a predetermined cylindrical outer peripheral surface, and a pressure punch and a knockout punch inserted into the mold hole to form a predetermined cylindrical outer peripheral surface. In obtaining a solid disk-shaped part with a hole or a ring-shaped part through subsequent central hole penetration, the precision method is characterized in that both punches are provided with a discharge passage for an incompressible medium such as lubricating oil. Tools for processing parts.