JPH04108921U - hole punch - Google Patents

Abstract

(57) [Summary] [Purpose] To improve durability by reducing wear and damage on the cutting edge, and to ensure that the center line of the punch matches the center line of the die during drilling. [Structure] A uniform chamfered portion 1c is formed over the entire circumference at the corner formed by the distal end surface 1a and the circumferential surface 1b of the main body 1.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention can be used in conjunction with a die to drill holes in steel plates and other plate materials. Regarding the hole punch that can be used.

0002

[Conventional technology]

Conventionally, the tip of this type of hole punch (also called a "piercing punch") is The tip surface is a plane that is perpendicular to the center line of the punch and perpendicular to the circumferential surface of the punch. The tip of the punch and the peripheral surface form a right-angled cutting edge.

0003

[Problem that the idea aims to solve]

However, conventional punches like the ones above have a right-angled cutting edge, so During drilling, punching force is applied rapidly, which can cause wear and damage to the cutting edge. It was early. As a result, burrs are likely to form in holes drilled in sheet metal, and the cutting edge is frequently touched. It needed to be polished.

0004 The purpose of this invention is to reduce the wear and damage of the cutting edge and to reduce the wear and damage of the punch when drilling holes. To provide a hole punch whose center line reliably matches the center line of a die.

[0005]

[Means to solve the problem]

The hole punch of the present invention has a uniform shape on the periphery of the tip of the punch body. It is characterized in that a uniform chamfered portion is formed.

[0006]

[Effect]

The hole punch of the present invention has a uniform shape on the periphery of the tip of the punch body. By forming a uniform chamfer, there is less wear and damage on the cutting edge, increasing durability. The re-sharpening cycle of the cutting edge can be extended.

[0007] Also, when drilling holes, the force applied to the chamfered part may cause the center line of the punch to change. Automatically aligns the punch itself to match the centerline of the die for focused Eliminates the occurrence of burrs.

[0008]

【Example】

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1, 1 is a main body of a punch 2, and a tip end surface 1a of the main body 1 is a plane perpendicular to a center line O ₁ of the punch 2. As shown in FIG. At the corner formed by the tip surface 1a and the peripheral surface 1b of the main body 1, that is, at the periphery of the tip of the main body 1, a uniform chamfered portion 1c is formed over the entire circumference. The corner formed by the chamfered portion 1c and the circumferential surface 1b serves as a cutting edge E. In this embodiment, the diameter D of the main body 1 is 9.9 mm. The angle θ between the surface of the chamfered portion 1c and the tip surface 1a is 8°, and the height H from the tip surface 1a to the cutting edge E is 0.2 mm.

[0010] Such a punch 2 is assembled into a press machine together with a die 3 and the like, and in the assembled state, the center line O ₁ of the punch 2 and the center line O ₂ of the die 3 coincide with each other. Then, by descending, the punch 2 punches out the sheet metal W on the die 3 to make a hole.

[0011] During the drilling process, first, the tip surface 1a of the main body 1 of the punch 2 comes into contact with the upper surface of the sheet metal W, and then the tip surface 1a bites into the sheet metal W. At this time, the chamfered portion 1c receives a uniform force from the sheet metal W over its entire circumference, and this force acts to align the centerline _O1 of the punch 1 with the centerline _O2 of the die 3. Thereafter, the cutting edge E punches through the sheet metal W to make a hole.

0012 Therefore, the punching force during drilling is determined by the tip surface 1a and the chamfered portion 1c. After being received, it joins the cutting edge E. Also, this is the area where the chamfered portion 1c is formed. The cutting edge angle of the cutting edge E becomes larger and the strength of the cutting edge increases. Also, the cutting edge E is Since the sheet metal W is punched uniformly over the entire circumference, intensive burrs are not generated. It will also cause you to smoke.

[0013]

[Effect of the idea]

As explained above, the hole punch of the present invention has a The structure has a uniform chamfered part over the entire circumference, which prevents wear and damage on the cutting edge. Reduces scratches, improves durability, and extends the resharpening cycle of the cutting edge. .

[0014] Also, when drilling holes, the force applied to the chamfered part may cause the center line of the punch to change. The punch itself is automatically centered to match the center line of the die. This eliminates the occurrence of concentrated burrs and allows the punch and die to be replaced with a press machine. When assembling, it is no longer necessary to precisely align the blades, reducing man-hours. You can also

[Brief explanation of drawings]

FIG. 1 is a side view of essential parts showing an embodiment of the present invention.

[Explanation of symbols]

1 Main body 1a Tip surface 1b Circumferential surface 1c Chamfered part 2 punch 3 dice E cutting edge W sheet metal

Claims (1)

[Scope of utility model registration request] 1. A hole punch characterized in that a uniform chamfer is formed on the periphery of the tip of the punch body over the entire circumference.