JPS62173047A - Manufacture of work having stepped hole - Google Patents

Abstract

PURPOSE:To shorten the pore working time of a work having a stepped hole by bringing a base material to plastic working stepwise at every process, and also, forming a pore by plastic working of a recess part and a blanking hole by extrusion forming. CONSTITUTION:A blank material is brought to extrusion forming, a work W1 in which a columnar recess part 22 has been formed in a shaft part 20 is obtained, and thereafter, a head part 21 is brought to upsetting, and a work W2 in which a columnar indentation part 23 has been formed in a head part 11 of a thick diameter is obtained. Subsequently, a thin wall part 24 is brought to blanking, a work W3 in which a blanking hole 25 has been formed is brought to forward extrusion forming, and a work W4 in which the shaft part 20 and the recess part 22 have been drawn into a shaft part 26 and the first prepared hole 27 of a small diameter, respectively, and also the blanking hole 25 has been drawn to the second prepared hole 28 is obtained. As for the work 4, the shaft part 26 and the prepared holes 27, 28, and also the indentation 23 are drawn and formed to a shaft part 10 and pores 12, 13, and also a funnel- shaped recess hole 14, respectively, and a formed part W is obtained. In this way, the pore working time of a desired work can be shortened.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a method for manufacturing a workpiece having a stepped hole, such as a flow control valve in an automobile power steering system or a flow control valve in other fluid equipment. It is related to.

(Prior Art) Conventionally, a stepped hole in a workpiece having a stepped hole, especially a stepped hole with a pore having a long length compared to the diameter, is usually
The holes are made by cutting with a drill.

For example, as shown in Fig. 4, a part of a hydraulic valve, i.e., a flow control valve for automobile power steering, is made of 8-dia.
A steel shaft member 1 having a shaft portion 1a of 3InMφX8#
111 first pore 3 and 1, 5 continuous to the pore 3
A stepped hole 2 consisting of a second pore 4 of mmφ×3al is formed. Currently, the stepped hole 2 is conventionally formed by cutting with a drill.

(Problems to be Solved by the Invention) However, when forming the stepped hole 2 by cutting with a conventional drill, the processing time required for the cutting is long and the production cost is high. was there.

Furthermore, in order to shorten the machining time, it is desirable to form the stepped hole by plastic working. However, forming pores with a length that is too long compared to the diameter by punching or punching is not recommended because it applies a large load to the tool (a punch to make the hole) that exceeds its usage limit. It is difficult to do so. In other words, if we compare the case where a 3φ pore is formed in the shaft part 1 with a shaft diameter of 8# with the case where a 5.6φ pore is formed, the tensile strength of the steel material will be 60 Ky/
In the case of #2, the punch load for a 5.6φ hole is approximately 65
85 K'J, the load stress applied to the tool is approximately 209,9
tcI/rum2, which is feasible, but the punch load for drilling a 3φ hole is approximately 2289 Kg, and the stress applied to the tool is approximately 324.9/mm2, values that are difficult to implement with existing tool materials. The cross-sectional shrinkage rate is 5
, in the case of 6φ, it is about 50%, and in the case of 3φ, it is about 91%.
This is a large value.

Furthermore, from the viewpoint of productivity, it is considered difficult to process the first pores 3 whose diameter exceeds about 2.5 times.

(Means for Solving the Problems) The present invention, which is intended to solve the problems in the conventional techniques described above, includes a step of forming a bottomed recess by extrusion molding a material, and a step of forming a recess of the material by extrusion molding. The step of punching punch holes on the bottom surface, and extrusion molding of the material to make the recesses into first pores and the punched holes into second pores, thereby forming a warp having stepped holes. The gist of the structure is that it consists of a process for manufacturing a product.

(Function) According to the above means, the material is plastically worked step by step in each step, and the pores are formed by plastic deformation of the recesses and punched holes by extrusion. This makes it possible to set the load applied to a tool (such as a punch) within the usage limit of the tool.

(Example) An example of the present invention will be described below with reference to FIGS. 1 to 3.

First, the product WA having a stepped hole manufactured by this manufacturing method is a flow control valve for an automobile power steering, and as shown in FIG. A bulging head 11 is formed.

A first pore 12 is formed in the shaft portion 10, and a second pore 13 continuous to the right end of the pore 12 is formed with a diameter smaller than that of the first pore 12. There is. The same pores 12 and 13 form a stepped hole. In this example, the shaft portion 10 is formed with 8JIllIφX 10m, the first pore 12 is formed with 3#φX 10mm, and the second pore 13 is formed with 1.5#φX 3m.

Further, a funnel-shaped recessed hole 14 is formed in the head 11 and continues to the right end of the second pore 13 .

A male thread 15 is formed on the outer periphery of the shaft portion 10, and stepped portions 16 and 17 are formed on the outer periphery of the end surfaces of the shaft portion 10 and the head portion 11, and a stepped portion outer periphery of the head portion 10 and the shaft portion 11 is formed. A recessed portion 18 is formed therein.

Thus, the product WA is obtained by forming the external thread 15 by rolling the workpiece W shown in FIG. It is something.

Next, the manufacturing process (first to fifth process) of the workpiece W having stepped holes of the product WA is shown in Figure 1, which shows the shape change of the material, and each operation of the five-stage press device The second shown
This will be explained with reference to the figure. Each figure in Figure 1 shows the processed product processed in each process, with the left half showing the external shape and the right half showing the cross section, and each figure in Figure 2 showing an example of the press equipment. The left half shows the cross section before processing, and the right half shows the cross section after processing.

In Fig. 1A, the material WO is shown, and the same material WO is
It is obtained by cutting a cylindrical shaft material made of steel (for example, low carbon steel, medium carbon steel, nickel chrome steel, etc.) into an appropriate length. Note that the material WO is 13φ×12#.

(First step) The material WO is pressed into the first press device P1 shown in FIG.
Through the first stage of plastic working (heading), the first processed product W1 shown in the opening of FIG. 1 is obtained.

That is, in the first press device P1, a forward extrusion pin P12 and a cylindrical ejector P13 surrounding the pin ID12 are arranged in a cavity of a die P11, and a punch P14 that is lowered from above the cavity is installed. There is.

After inserting the WO into the cavity of the die P11, the first
A next processed product W1 is formed.

In the primary processed product W1, the shaft portion 20 of the lower half is subjected to extrusion process J.
:The shaft diameter is formed smaller than the cable material WO, and at the same time, a columnar recess 22 is formed in the coaxial portion 20.

That is, both the shaft diameter of the shaft portion 20 and the hole diameter of the recess 22 are processed by forward extrusion.

In addition, the head 21 whose shaft diameter does not change is 13φ×5#, and the shaft portion 2
0 is formed in the order of 9, 2φ×7#, and the recesses 22 are formed in the order of 5φ×6.

(Second step) The first processed product W1 is subjected to the second stage of plastic working (simultaneous upsetting and extrusion working) using the second press @P2 shown in the opening of Figure 2. This is the secondary processed product W2 shown in FIG. 1C.

The second Zunawaji press device 2 includes a forward extrusion pin P22 and a cylindrical ejector P23 surrounding the pin P22 in a cavity of a die P21, and a punch P24 that is lowered from above the cavity. It is being Then, the first processed product W1 is placed in the cavity of the die P21.
After inserting the punch P24, the punch P24 is lowered to form the second processed product W2.

In the secondary workpiece W2, the head 21 of the primary workpiece W1 is upset-processed into the head 1 with a larger shaft diameter, and at the same time, a cylindrical recess 23 is formed in the microscope part 11. A thin wall portion 24 is formed between the recessed portion 22 and the recessed portion 23 . The head 11 is 15φ x 7m, and the recess 23 is 1
They are each formed to have a diameter of 0φX 4 mm, and the thin wall portion 24
It is formed to have a thickness of 3 mm.

(Third step) The secondary workpiece W2 is produced by the third stage of plastic working (punching) by the third press device P3 shown in FIG. It is referred to as tertiary processed product W3.

That is, in the third press device P3, a hole punch P32 and a cylindrical ejector P33 surrounding the punch P32 are arranged in the cavity of the die P31, and a receiver punch P34 is provided above the cavity. . After the secondary workpiece W2 is put into the cavity of the die P31, the hole is opened by raising the punch P32, and the punching hole 25 is punched by the tip of the punch P32. A product W3 is formed.

The tertiary processed product W3 is obtained by punching holes 25 in the thin wall portion 24 of the secondary processed product W2. Note that the punched hole 25 is formed with a diameter of 4φ.

(Fourth step) The tertiary processed product W3 is produced by the fourth stage of plastic working (forward extrusion) by the fourth press device NP/l shown in the opening of FIG. This is referred to as the fourth processed product W4.

That is, in the fourth press device P4, a forward extrusion pin P42 and a cylindrical ejector P43 surrounding the pin Pd2 are arranged in the cavity of the die P41, and a punch P44 that is lowered from above the cavity is provided. There is. Note that a core pin P45 is protruded from the tip of the extrusion pin P42. After putting the tertiary workpiece W3 into the cavity of the die P, 41, by lowering the punch P44, both the shaft diameter and the hole diameter are extruded forward, and the fourth workpiece W4 is formed. Ru.

In the fourth processed product W4, the shaft portion 20 of the third processed product W3 is further drawn into a smaller diameter shaft portion 26, the recessed portion 22 is used as a first prepared hole 27, and the punched hole 25 is formed as a second prepared hole 27. Pilot hole 28
It is said that The shaft portion 26 is 7.2φ×5M1, the first pilot hole 27 is 3φ×6M, and the second pilot hole 28 is 1.5φ×3M1.
The head 21 is formed into a size of 15φ×5.

(Fifth step) The fourth processed product W4 is produced by the work W4 shown in FIG. It is said that

That is, the fifth press device P5 includes a cylindrical ejector P53 that surrounds a front extrusion pin P52 and a front extrusion pin P52 in a cavity of a die P51, and a punch P54 that is lowered from above the cavity. There is. Note that a core bottle P55 projects from the tip of the push-out pin P52. Then, after the fourth processed product W4 is put into the cavity of the die P51, the workpiece W is formed by lowering the bunch P54.

In the workpiece W, the shaft portion 26 of the fourth processed product W4 is further drawn to become the shaft portion 10, and the first prepared hole 27 is formed as a first hole.
pores 12 and second pores 13.

Note that the depression MS23 in the head 11 is a funnel-shaped recess 14.

In this way, the material WO is plastically worked in stages, and the workpiece W having the stepped hole is manufactured.

In addition, in the above step ①, press device P4. P5 die P41. P51, an extrusion pin P42. with a core pin P45°P55 at the tip. Since P52 is located, pore 1
2 and 13 can be formed with high precision.

In addition, in the fourth step of plastic working, due to the punched hole 25 in the tertiary workpiece W3, cracks or pull-outs are expected to occur at the upper corner of the first pilot hole 27.
This effectively prevents flops.

(Effects of the Invention) In other words, the present invention is characterized in that the material is plastically worked step by step in each step, and the pores are formed by plastic processing of the recesses and punched holes formed by extrusion molding.
Since it is formed by t-deformation, it is possible to set the cart applied to the tool within the usage limit of the tool, so unlike cutting with a conventional drill, it is possible to shorten the processing time for fine holes. This has the effect of reducing production costs.

[Brief explanation of drawings]

Figures 1 to 3 show one embodiment of the present invention.
The illustrations show the processed products for each process.
The left half shows the outline and the right half shows the cross section, respectively.
In addition, Figures 2A to 2E show an example of a press machine; the left half shows the cross section before processing, the right half shows the cross section after processing, and Fig. 3 shows the product. , the upper half shows the outer shape, the right half shows the cross section, and FIG. 4 is a cross-sectional view showing a product produced by a conventional manufacturing method. 12...First pore 13...Second pore 2
2... Concavity 25... Punching hole W...
Work WO...Amount of material Request person Toyo Fastener Co., Ltd. Agent Patent attorney Hidehiko Okada (
Figure 1 (2) Figure 1 (T:1) Figure 1 (C) Figure 1 (
e) Figure 1 (f) Figure 8 Figure 4

Claims (1)

[Claims] A step of forming a bottomed recess by extrusion molding a material, a step of punching a punched hole in the bottom of the recess of the material, and a step of forming a first narrow recess by extrusion molding the material. 1. A method for manufacturing a workpiece having a stepped hole, the method comprising the step of manufacturing a workpiece having a stepped hole by forming a hole and making the punched hole a second fine hole.