JPH07204771A - Separation working method for pipe material and device therefor - Google Patents

Abstract

PURPOSE:To execute a serration work with small forming load an to obtain pipe parts of high quality without galling. CONSTITUTION:At the time of swaging the end part of the pipe material 1 by pressurizing the pipe material 1 in a lower side die 5 with an upper side pipe material pressing 7, a punch 8 which has a serration mold 9 for forming the serration to the inner surface of the working part at the time of swaging the pipe material 1 at the tip part and can be inserted in the pipe material 1, is arranged in the upper side die. Then, at the time of pressurizing the pipe material 1, the punch 8 is inserted into the pipe material 1 to execute the swaging while restricting the inner surface of this pipe material 1. At the same time, the serration is executed in the inner surface of the working part by pushing the swaged part to the serration mold 9 and deforming.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe material serration processing method and device for processing serrations on the inner surface of the pipe end of the pipe material.

[0002]

2. Description of the Related Art For example, as shown in FIG. 8, a general method for processing a serration 2, for example, a pipe part 3 having involute serrations on the inner surface of the pipe end of a pipe material 1 is as follows.
There is machining or pressing. FIG. 9 is a sectional view showing the shape of parts for each machining process in the case of machining.
This will be described with reference to (a) to (d). First, as a first step, the pipe material 101 shown in FIG. 9A is subjected to inner surface processing (reference numeral 104 is given) as shown in FIG. 9B. Second
As a step, outer surface processing (denoted by reference numeral 105) is performed on the pipe material 101 as shown in FIG. Next, as a third step, the pipe member 101 is subjected to serration processing as shown in (d) to obtain a pipe component 103 having serrations 102. Such machining results in a large number of steps and high cost.

Further, the case of press working will be described with reference to FIG. 10 which shows a schematic sectional view of a working process and FIG. 11 which shows a sectional view of a component shape for each working process. In this case, as the first step, the pipe member 201 shown in FIG.
Is set in the lower die side die 204 as shown in FIG. 10 (a), and then the upper die side punch 205 is pressure-inserted into the tubular material 201 as shown in FIG. 10 (b) to expand ( Pipe end expansion processing) is performed to obtain a pipe material 201 shown in FIG. Next, as a second step, a punch 206 having a serration die 207 at its tip as shown in FIG. 10C is inserted into the pipe 201 by pressure as shown in FIG. By performing the above, the pipe part 203 having the serrations 202 shown in FIG. 11C is obtained. According to such press working (this is called 2-step press working), a total of 2
Since the pipe component 203 is obtained in the process, the number of processes is reduced by one compared with the above-mentioned machining, but since the relationship between the die 204 and the punch 206 makes it impossible to perform the serration process over the entire pipe end, FIG. As shown in (c), the unprocessed portion 208 remains at the lower end of the pipe component 203.

As a solution to the problems of the above-mentioned machining and two-step press working, the following one-step press working has been proposed. This one-step press working will be described with reference to FIG. 12 which shows the working process in a schematic sectional view and FIG. 13 which shows the component shape in each working process in the sectional view. Figure 1
After the pipe material 301 shown in FIG. 3A is set in the lower die 305 as shown in FIG.
12 is pressed into the die 305 as shown in FIG. 12B by the upper die side tube material retainer 306 to perform swaging (tube end drawing), and at the same time, the die 305 is attached to the inner surface of the tube end. Serration mold 3 on the bottom of the mold cavity
By performing the serration process by relatively pressing and inserting 07, the pipe part 303 having the serration 302 shown in FIG. 13B can be obtained by the press process of one step.

[0005]

According to the above-mentioned one-step press working, since the pipe material 301 is pressure-inserted into the molding space 304 between the die 305 and the serration die 307,
The friction of the pipe material 301 against the die 305 and the serration die 307 is considerably large, and a large forming load is required. Further, when the forming load is large, the buckling of the pipe material 301 must be taken into consideration. Therefore, as shown in FIG. 12, the guide 309 for restraining the inner surface of the pipe material and the guide 30 thereof.
A buckling prevention structure 308 constructed by incorporating a spring 310 for urging 9 into the tubular material retainer 306 is indispensable, and the mold structure becomes complicated. Further, since the serration die 307 is relatively pressure-inserted into the pipe material 301, lubrication is easily broken by rubbing, which may cause galling and deteriorate the quality of the pipe component 303.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object thereof is to obtain a high-quality pipe part which can perform serration processing with a small forming load and is free from galling. It is intended to provide a serration method for pipe material and a device therefor.

[0007]

In order to achieve the above-mentioned object, the invention according to claim 1 inserts a pipe material into a lower die by pressurizing it with an upper die pipe retainer to insert a pipe end of the pipe die. When performing swaging, a punch having a serration die at its tip is provided on the upper die side, and the swaging is performed while restraining the inner surface of the tubular material by inserting the punch into the tubular material. At the same time, it is a serration method for a pipe material, in which the inner surface of the processed portion is subjected to serration processing by utilizing plastic deformation of the processed portion into a serration shape by the swaging processing. According to a second aspect of the present invention, there is provided a lower die for reducing the outer diameter of the pipe end of the tubular material, an upper die side presser foot for inserting the tubular material into the die under pressure, and an upper die side provided inside the tubular material. A serration device for a pipe material, comprising: a punch to be inserted into a pipe; and a serration die which is provided at a tip end portion of the punch and forms a serration on an inner surface of a processing portion for swaging the pipe material. According to a third aspect of the invention, in the pipe material serration processing apparatus according to the second aspect, the die is divided into an upper half body and a lower half body, and the upper half body is suspended so as to be able to move up and down to the upper mold side. This is a pipe material serration processing device.

[0008]

According to the pipe material serration method of the first aspect, friction against the die due to the swaging processing of the pipe material is unavoidable, but friction does not occur on the inner surface of the pipe end without generating friction against the serration die of the punch. Serration processing is possible. In the pipe material serration processing apparatus according to claim 2, when the pipe material is set in the lower die side die and pressure-inserted by the upper die side tube retainer, the sway is performed while the inner surface of the pipe material is restrained by the punch inserted in the pipe material. At the same time that the swaging process is performed, the serration process is performed on the inner surface of the process part by utilizing the plastic deformation of the process part to the serration type by the swaging process. According to the pipe material serration processing apparatus of claim 3, the pipe material is set in the lower half of the die, and the upper half of the die is joined to the lower die as the upper die descends, thereby forming the original die. Function as. Further, with the rise of the upper mold after the serration process of the pipe material, the upper half of the die separates from the lower half and rises to form a space for inserting the pipe material between the two half bodies.

[0009]

【Example】

[Embodiment 1] Embodiment 1 will be described with reference to the explanatory view of the serration processing apparatus in FIG. FIG. 1A is a sectional view showing a state immediately before a punch is inserted into a pipe material, FIG. 1B is a state during swaging, and FIG. In addition, this device is a pipe component 3 having serrations 2 on the inner surface of the pipe end of the pipe material 1 shown in FIG.
Is manufactured. The lower die side die 5 has a die hole 6 into which the pipe material 1 to be swaged is inserted. The mold cavity 6 includes a non-processed portion 6a formed at the outer diameter of the raw pipe at the upper portion of the drawing and a processed portion 6 formed at a diameter smaller than the outer diameter of the raw pipe.
c is continuous with the tapered portion 6b. Dice 5
Is fixed on a lower die holder of a press (not shown). The pipe material 1 put into the mold cavity 6 is obtained by cutting a long pipe into a predetermined length, and is usually subjected to a bonder treatment.

A round bar-shaped tube material retainer 7 for pressing the tube material 1 against the die 5 has an outer diameter substantially equal to the outer diameter of the raw tube of the tube material 1 and is attached in a hanging manner to an upper die holder of a press machine (not shown). Has been. A round bar-shaped punch 8 to be inserted into the pipe material 1 is integrally formed at a tip end portion (lower end portion in the drawing) of the pipe material retainer 7. The punch 8 is formed to have an outer diameter substantially equal to the inner diameter of the tube of the pipe material 1 and an axial length substantially equal to the non-machined portion 6a of the die hole 6. Further, at the tip of the punch 8, there is provided a serration die 9 having an axial length slightly longer than the processing portion 6c of the die hole 6.
The serration die 9 is fastened to the front end surface of the punch 8 with a mounting bolt 10.

The operation of the above serration processing apparatus will be described. As shown in FIG. 1 (a), after the pipe material 1 is set in the non-processed portion 6a of the die hole 6 of the die 5, the pipe material presser 7 is lowered with the operation of the press machine, and the punch 8 is punched.
Are sequentially inserted into the pipe material 1, and the pipe material retainer 7 is attached to the pipe material 1.
Abuts on the upper end surface of the (see the chain double-dashed line in FIG. 1A). When the pipe material retainer 7 is further lowered, the lower pipe end of the pipe material 1 is tapered by the taper portion 6 of the die hole 6 of the die 5 as shown in FIG.
Swage processing is performed as the pressure is inserted into the processing portion 6c via b. Simultaneously with this swaging, the processed portion is plastically deformed into the serration die 9 (specifically, the die peripheral surface), so that the inner surface of the processed portion is subjected to serration processing. When the lowering of the punch 8 is completed, the swaging process and the serration process are completed as shown in FIG. After the processing is completed, the pipe material pressing member 7 is lifted by the pressing machine to move the punch 8 to the pipe component 3
Should be removed.

According to the above serration processing apparatus,
Although friction against the die 5 due to swaging of the pipe material 1 is unavoidable, serration can be performed on the inner surface of the pipe end without causing friction against the serration die 9 of the punch 8. Therefore, the serration process can be performed with a smaller forming load as compared with the conventional one-step pressing process, and a high-quality pipe component 3 free from galling due to the rubbing of the pipe material 1 against the serration mold 9 can be obtained. Further, since the forming load is small, the consideration of buckling of the pipe material 1 is reduced, and in addition, the punch 8 can prevent the buckling of the pipe material 1, and a simple mold that does not require a special buckling prevention structure. It can be a structure.

Since the serration die 9 in this embodiment is formed separately from the punch 8 and is attached to the punch 8 with the attaching bolts 10, the serration die 9 (specifically, die blade) is wire-discharged. Only the die 9 can be obtained by machining, and the die cost can be reduced as compared with the case where the serration die blade is electric discharge machined at the tip of the punch 8.

[Embodiment 2] Embodiment 2 will be described with reference to FIGS.
Will be described with reference to. Since this example is a modification of the first embodiment, the same reference numerals are given to the parts which are considered to be the same as or equivalent to those of the first embodiment, and the duplicate description will be omitted. Further, the same concept is applied to the following embodiments, and a duplicate description will be omitted. In FIG. 2, which is a sectional view showing a state before the operation of the serration processing apparatus, a proper number of pieces are provided on the lower die holder 12 of the pressing machine to which the die 5 is fixed and which are located in the peripheral portion of the die 5 (the figure shows (Two of them are shown)
The guide post 13 is installed upright. On the other hand, unlike the first embodiment, the tube material pressing member 7 and the punch 8 are configured as separate parts, and the punch 8 having the serration mold 9 is attached to the upper mold holder 14 of the press machine in a hanging shape. Further, the pipe material retainer 7 is integrally provided on the retainer plate 15, and has the same tubular shape as the pipe material 1 and projects to the lower surface of the plate. The pressing plate 15 can move up and down in a horizontal state with respect to the guide post 13 and the spring 1
It is supported in a state of being urged upward by 6 and is prevented from coming off by a stopper 13 a at the upper end of the guide post 13. The punch 8 is slidably inserted into the tube material retainer 7 of the retainer plate 15.

The operation of the above serration processing apparatus will be described. In the state before operation shown in FIG. 2, the pipe material 1 is set in the die hole 6 of the die 5 as shown by the chain double-dashed line. Then, the press machine operates and the upper die holder 1
When 4 descends, the punch 8 descends inside the tube material retainer 7 of the retainer plate 15, and the upper die holder 14 contacts the retainer plate 15. This state is shown in FIG. When the upper die holder 14 is further lowered, the punches 8 are sequentially inserted into the pipe material 1, and the pressing plate 15 is pushed down against the elasticity of the spring 16, so that the pipe material pressing member 7 is placed on the upper end surface of the pipe material 1. Abut. This state is shown by the chain double-dashed line in FIG.

When the upper die holder 14 is further lowered, the pipe material retainer 7 and the punch 8 are simultaneously lowered, and the pipe material retainer 7
Thereby, the pipe material 1 is pressure-inserted into the die 5. Then, similarly to the above, swaging is performed as the pipe material 1 is pushed into the die 5, and at the same time, the swaging portion is plastically deformed into the serration die 9, so that the inner surface of the processing portion is serrated. The finished state is shown in FIG.

After processing, the upper die holder 1 is pressed by a press machine.
When 4 rises, the pressing plate 15 is floated by the elasticity of the spring 16, and the pipe component is pulled out from the die hole 6 of the die 5 while being attached to the punch 8. Further, the pressing plate 15 is the stopper 13a of the guide post 13.
(See FIG. 3), the upper die holder 14 is further raised, and the pipe component is pulled out from the punch 8 by the relative movement of the pipe material retainer 7 and the punch 8. afterwards,
The upper die holder 14 rises to the original position (see FIG. 2).

According to the serration processing apparatus of this embodiment, the pipe material retainer 7 and the punch 8 are provided separately, and the pipe material retainer 7 is interlocked with the elevation of the punch 8.
The pipe part can be automatically pulled out from.

[Embodiment 3] Embodiment 3 will be described with reference to FIGS.
Will be described with reference to. In this example, the serration processing apparatus of Example 2 is improved, and the die 5 is divided into an upper half body 51 and a lower half body 52, as shown in the sectional view of FIG. . The lower half body 52 is fixed to the lower die holder 12. In addition, an appropriate number of suspension poles 18 (two of which are shown in the figure) are erected on the upper surface of the upper half body 51, and the suspension poles 18 are slidably connected to the upper die holder 14. The upper half body 51 is suspended by the upper mold holder 14 so as to be able to move up and down. The suspension pole 18 penetrates through an opening provided in the pressing plate 15, and its tip is prevented from coming off by a stopper 18a. The upper half body 51 is always urged downward by the spring 19. Further, in the state before the operation, the pipe material retainer 7 of the retainer plate 15 is inserted into the mold cavity 6 of the upper half body 51, and the upper half body 51 is separated from the lower half body 52, and as shown in FIG. Is at a position higher than the solid line state (see the chain double-dashed line in FIG. 5).

The operation of the above serration processing apparatus will be described. In a state before the upper half body 51 of the die is shown by a chain double-dashed line in FIG. 5, from the charging space between the upper half body 51 and the lower half body 52 of the die, the pipe material 1 is indicated by a two-dot chain line in FIG. It is set in the mold cavity 6 of the lower half 52 as shown by. Then, the press machine operates, the upper half body 51 descends together with the upper die holder 14, and the punch 8 descends inside the tube material retainer 7 of the retainer plate 15, as shown by the solid line in FIG. 14 abuts on the presser plate 15.

When the upper mold holder 14 is further lowered, FIG.
As shown in FIG. 3, the pressing plate 15 is pushed down against the elasticity of the spring 16 so that the pipe material pressing member 7 contacts the upper end surface of the pipe material 1. At the same time, the punch 8 is inserted into the pipe material 1, the mold cavity 6 of the upper half body 51 is fitted into the pipe material 1, the upper half body 51 is joined onto the lower half body 52, and the original die 5 is formed. To form.

When the upper die holder 14 is further lowered, the pipe material retainer 7 and the punch 8 are simultaneously lowered, and the pipe material retainer 7
Thereby, the pipe material 1 is pressure-inserted into the die 5. Then, similarly to the above, swaging is performed as the pipe material 1 is pushed into the die, and at the same time, the swaging portion plastically deforms into the serration die 9, so that the inner surface of the processing portion is serrated. The finished state is shown in FIG. At this time, the upper mold holder 14 compresses the spring 19.

After that, when the upper die holder 14 is lifted by the pressing machine, the pressing plate 15 is levitated by the elasticity of the spring 16, and the punch 8 is pulled out from the die hole 6 of the die 5 with the pipe parts still attached. Further, the spring 19 is elastically restored until the upper die holder 14 is prevented from coming off by the stopper 18a of the suspension pole 18 of the upper half body 51. When the upper die holder 14 further rises, the pressing plate 15 is levitated by the elasticity of the spring 16, and the upper half body 51 rises through the suspension pole 18 and separates from the lower half body 52. After the pressing plate 15 comes into contact with the stopper 13a of the guide post 13 (see FIG.
Further, as the upper die holder 14 is further raised, the pipe component is pulled out from the punch 8 by the relative movement of the pipe material pressing member 7 and the punch 8. After that, the upper mold rises to the original position (see the chain double-dashed line in FIG. 5).

According to the serration processing apparatus of this example, since the upper half 51 of the die 5 is attached to the upper die side, the minimum lifting stroke required for the upper die can be shortened, so that the die 5 is divided. It becomes possible to adopt a small stroke press machine compared to the case where it is not done. For example, in the apparatus of Example 2, when processing a pipe material 1 having a length of 100 mm, the minimum elevating stroke required for the upper mold is for loading the pipe material 1 and removing the formed pipe parts. With the required stroke amount and the stroke amount required for the swaging process of the pipe material 1, a stroke equivalent to twice the length of the pipe material 1, that is, 220 to 230 mm, is required. Since the upper half 51 of No. 5 is attached to the upper die side, the stroke corresponding to the overlap between the punch 8 and the upper half 51, that is, about 50 mm, can be shortened, which is required for the upper die. The minimum lifting stroke is 170-180 mm.

[0025]

Since the present invention is constructed as described above, it has the following effects. According to the serration method for a pipe material according to the first aspect of the present invention, friction does not occur with respect to the serration die of the punch,
Since the serration process can be performed on the inner surface of the pipe end, the process can be performed with a smaller forming load as compared with the conventional one-step pressing process, and a high quality pipe component free from galling due to rubbing of the pipe material with the serration mold can be obtained.
Furthermore, since the forming load is small, the consideration of tube buckling is reduced, and in addition, the punch can prevent buckling of the tube, and a serration with a simple die structure that does not require a special buckling prevention structure. It can be processed by a processing device. According to the pipe material serration processing apparatus of claim 2, since the pipe material serration processing can be performed by the pipe material serration processing method of claim 1, the conventional pipe serration processing apparatus can be used.
It is possible to manufacture high-quality pipe parts free from galling with a device that has a smaller molding load and a simpler die structure than process press processing. According to the pipe material serration processing apparatus of claim 3, since the upper half of the die is attached to the upper die side, the minimum lifting stroke required for the upper die can be shortened, so that the die is not divided. Compared with the case, it is possible to adopt a small stroke press machine.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a serration processing apparatus according to a first embodiment.

FIG. 2 is a sectional view showing a serration processing apparatus according to a second embodiment.

FIG. 3 is a cross-sectional view showing an intermediate state of processing of the processing apparatus of FIG.

FIG. 4 is a cross-sectional view showing a state in which the processing apparatus of FIG. 2 has finished processing.

FIG. 5 is a sectional view showing a serration processing apparatus according to a third embodiment.

6 is a cross-sectional view showing an intermediate state of processing of the processing apparatus of FIG.

7 is a cross-sectional view showing a state where the processing apparatus of FIG. 5 has finished processing.

FIG. 8 is a half sectional view of a pipe component.

FIG. 9 is a cross-sectional view showing a component shape for each process by machining.

FIG. 10 is an explanatory diagram showing a working process by a two-step press working.

FIG. 11 is a cross-sectional view showing the shape of a part formed by two-step press working.

FIG. 12 is an explanatory view showing a working process by one-step press working.

FIG. 13 is a cross-sectional view showing the shape of a part formed by a one-step press working.

[Explanation of symbols]

 1 Tubular material 5 Die 7 Tubular material retainer 8 Punch 9 Serration type

Claims (3)

[Claims] 1. A punch having a serration die at its tip on the upper die side when the pipe material is pressure-inserted into the lower die side die by a top die side tube retainer and the pipe end of the pipe material is swaged. By providing this punch into the pipe, the swaging is performed while restraining the inner surface of the pipe, and at the same time, the plastic deformation of the processed portion into the serration mold by the swaging is utilized. A serration method for pipe materials that performs serration processing on the inner surface of the processing part. 2. A lower die side die for reducing the outer diameter of the pipe end of the pipe material, an upper die side pipe material retainer for pressurizing and inserting the pipe material into the die, and an upper die side die member provided on the upper die side and inserted into the pipe material. A pipe material serration apparatus, comprising: a punch; and a serration die which is provided at a tip portion of the punch and forms a serration on an inner surface of a processing portion for swaging the pipe material. 3. The pipe material serration processing apparatus according to claim 2, wherein the die is divided into an upper half body and a lower half body, and the upper half body is suspended so as to be capable of moving up and down on the upper die side.
Pipe material serration processing device.