JP2746686B2 - Punching tool for spinning holes - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a punch tool used for forming a spinning hole of a spinneret for wet spinning chemical fibers such as acrylic and rayon, and particularly to a punching plate. The present invention relates to an improvement of a second punch tool used for driving into a first punched hole or for reaming.

(Prior Art) In order to form a spin hole of a spinneret used for wet spinning of a chemical fiber such as acrylic or rayon, first, FIG.
As shown in FIG. 2, a first punch hole 2 is formed in a base plate 1 with a first punch tool, and then a second punch tool is driven into the first punch hole 2 to form a second punch hole as shown in FIG. 3 and then the outer projecting portion 4 of the second punched hole 3 is polished to penetrate the second punched hole 3 as shown in FIG. 2c, and then the penetrated second punched hole 3 is The spinning hole 5 was obtained by reaming with a two-punch tool as shown in FIG. 2d.

As shown in FIG. 3, a conventional second punch tool used for forming the second punch hole 3 and finishing the reamer has a thin punch body 8 made of carbide in a hole 7 at the center of the tip end surface of a shank portion 6 made of high-speed steel. It is fitted and brazed around the periphery of the hole 7.

(Problems to be Solved by the Invention) The conventional second punch tool 9 is easily deformed because the shank portion 6 is made of high-speed steel. Since the chucking position at the time of boring is different, centering was required at each operation. Therefore, the number of manufacturing steps is large, and the cores of the shank portion 6 and the tip shaping portion of the punch body 8 are hard to come out, so that the processing accuracy when punch holes are processed is poor.

Therefore, as shown in FIG. 4, there has been proposed a second punch tool 9 'in which the shank portion 6 and the punch body 8 are integrally formed of carbide and the punch body 8 is made thin and long.

This second punch tool 9 'can accurately and easily center the shank portion 6 and the punch main body 8, can obtain the degree of freedom (flexibility) of the punch main body 8, and can break the punch hole during machining. There is no.

However, the second punch tool 9 ′ is
However, when the front end shaping portion of the punch body 8 is shaped, it is easy to shake and the shaping is difficult.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a spinning hole drilling punch tool that facilitates shaping of a tip shaping portion of a punch body.

(Means for Solving the Problems) A punch tool for spinning a spinning hole according to the present invention for solving the above problems is a second punch comprising a punch body and a shank portion driven into a first punch hole formed in a die plate. All the tools are made of carbide and the punch body is made thin and long, and a thick auxiliary shank having the same diameter as the shank is provided in the middle.

(Function) As described above, the spinning tool for punching a spinning hole according to the present invention has a good centering accuracy between the shank portion and the punch body since the shank portion and the punch body are integrated, and the length of the punch body is long. Since the length is long, a degree of freedom (flexibility) is obtained, and breakage is prevented. In addition, since the second shank portion is provided in the middle of the punch body, the auxiliary shank portion is chucked when shaping the tip shaping portion of the punch body. As a result, the deflection of the punch body is prevented, the shaping process is facilitated, and a highly accurate tip shaping portion is obtained.

(Embodiment) An embodiment of the punch tool for forming a spinning hole according to the present invention will be described with reference to FIG. 1. Reference numeral 10 denotes a second punching tool for punching into a first punch hole 2 formed in a die plate 1 shown in FIG. It is a punch tool and the whole is made of carbide and has a total length of 50mm. The shank portion 11 of the second punch tool 10 has a diameter of 2 mm and a length of 25 mm, and the punch body 12 has a diameter of 1 mm and a length of 5 mm.
An auxiliary shank 13 having a diameter of 2 mm and a length of 15 mm is provided at a distance of 5 mm from 11.

The second punch tool 10 of the embodiment configured as described above,
As shown in FIG. 3, a hole 7 having a diameter of 1.2 mm and a depth of 5 mm at the center of the tip end surface of a shank portion 6 made of high-speed steel having a diameter of 2 mm and a length of 50 mm.
A punch body 8 made of carbide and having a diameter of 1 mm and a length of 10 mm is fitted thereinto and brazed at the periphery of the hole 7, and a second punch tool 9 of a conventional example, as shown in FIG. A second punch tool 9 'of an improved example in which a shank portion 6 having a length of 30 mm and a punch body 8 having a diameter of 1 mm and a length of 20 mm are formed integrally with a carbide.
And a second punching tool formed by punching a second punching tool into 20,000 first punching holes having a diameter of 0.3 mm formed in a stainless steel base plate having a diameter of 200 mm and a thickness of 1.0 mm, respectively. 2% of the second punch hole formed by driving the second punch tool 9 of the conventional example is misaligned with the original first punch hole by 1%.
On the other hand, the second punched hole formed by driving the second punched tool 9 'of the improved example is misaligned by only 0.05% from the original first punched hole. The second punched hole formed by driving the tool 10 was slightly out of alignment with the original first punched hole at 0.01%, and the processing accuracy was extremely good.

Further, the second punch tool 9 of the conventional example at the time of punching with each of the second punch tools has a small amount of deflection with respect to the load of the punch body 8 and a small degree of freedom (flexibility). The punch tools 9 'and 10 are the punch body 8,
Since there is a large amount of deflection under the load of 12 and a sufficient degree of freedom (flexibility), the punch bodies 8, 12
Did not break.

As described above, the processing accuracy of the second punch hole by the second punch tool 10 of the embodiment is extremely good because the shank portion 11 and the punch body 12 are integrated with each other. The centering accuracy of the punch
The chucking of the auxiliary shank portion 13 when shaping the tip shaping portion prevents the punch body 12 from oscillating, facilitating the shaping process, and obtaining a highly accurate tip shaping portion. This is because the main body 12 has a sufficient degree of freedom (flexibility) as described above, and the punch main body 12 does not break when the punch hole is processed.

(Effects of the Invention) As can be seen from the above description, in the spinning tool for punching a spinning hole according to the present invention, since the shank portion and the punch main body are formed of a solid carbide body, the centering of the shank portion and the punch main body is accurately performed. Since the auxiliary shank portion is provided in the middle of the punch main body, when shaping the tip shaping portion of the punch main body, the auxiliary shank portion is chucked to prevent the swing of the punch main body. Since a highly accurate tip shaping portion can be easily obtained, and the amount of deflection against the load of the punch body is large, and the punch body has a sufficient degree of freedom (flexibility).
It is possible to obtain a second punch hole and a spinning hole with extremely high processing accuracy.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a punching tool for forming a spinning hole according to the present invention, FIGS. 2a to 2d are views showing a process of forming a spinning hole of a spinneret, and FIG. FIG. 4 is a diagram showing a punch tool for drilling holes, and FIG. 4 is a diagram showing an improved example of a conventional punch tool for drilling spinning holes. 10 ... Punching tool for spinning holes (second punching tool), 11
… Shank part, 12… Punch body, 13… Auxiliary shank part.

Claims (1)

(57) [Claims] A second punch tool consisting of a punch body and a shank part to be punched into a first punch hole formed in a base plate is entirely formed of carbide, and the punch body is made thin and long, and the same as the shank part in the middle. A punch tool for spinning a spinning hole, characterized in that a thick auxiliary shank portion is provided.