JPH01104421A - Chamfering and burring method - Google Patents

Abstract

PURPOSE:To efficiently execute chamfering and burring without executing a cutting process by piercing a metallic plate by press working, and thereafter, chamfering the hole by a chamfering punch, and subsequently, bringing the hole of the metallic plate to burring by a burring punch. CONSTITUTION:A metallic plate is pierced by press working. A product 4 having this prepared hole is set to a chamfering die 2 by a chamfering plate holder 3. Subsequently, a chamfering punch 1 having a chamfering tapered part A is allowed to descend, and by pressing the upper face B of the hole of the product 4 by the tapered part A, chamfering is executed. A chamfered product 8 which has been obtained in such a way is set to a burring die 7 by a burring plate holder 6. Next, a burring punch 5 having a burring punch flat part C is allowed to descend, the hole of the metallic plate is brought to burring by a press, and a chamfering and burring product 9 is obtained.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a chamfering and burring method 5 for press-formed parts, and is used for burring an automobile brake booster. .

(Prior Art) As a prior art related to the present invention, a processing method is used in which the end of the burring portion is chamfered with a drilling machine as a post-pressing process, and then the burring is formed with a press.

(Problems to be Solved by the Invention) However, there are problems in that the number of man-hours is unbalanced between the pressing and cutting processes, cutting takes too much time, and chips are generated in the cutting process.

The technical object of the present invention is to provide a processing method for chamfering burrings of press-processed parts in approximately the same time as press processing without using a cutting process.

[Structure of the invention]

(Means for solving the problems) The technical measures taken to solve the above technical problems are as follows. That is, after drilling a hole in a metal plate by press working, a chamfer is formed in the hole in the metal plate using a chamfering punch having a chamfer tapered portion and a chamfering die, and then a chamfer is formed in the hole in the metal plate using a burring punch having a burring punch flat portion and a burring die. This is a chamfering burring method using a press, in which a burring is formed by purling a hole in a metal plate using a press.

(Operation) The technical means operates as follows. In other words, since the chamfering punch has a tapered part, this taper part presses the top surface of the press working hole in the metal plate to chamfer the end, and then the step part of the burring punch presses the top surface of the press working hole. This type of burring is performed by using the burring method, and the burring part can be formed correctly without generating cutting powder.

(Example) Examples will be described below.

In Figures 1 and 2, l stands for a chamfer punch.

2 is a chamfering die, 3 is a chamfer temporary press, and 4 is a product before processing.

In Figures 3 and 4, 5 is a burring punch and 6 is a burring punch.
is a burring temporary press, 7 is a burring die, and 8 is a chamfered product.

To describe the function of the above structure, as shown in FIG. 1, a product 4 with a prepared hole is set in the chamfering die 2. Fig. 5 shows an enlarged view of the product.

As shown in FIG. 2, when the chamfering punch 1 is lowered, the tapered section A of the chamfering punch 1 hits the B section of the product 4, and the product 4 is chamfered as shown at 4a in FIG. 6.

Next, as shown in FIG. 3, the chamfered product 8 is set in the burring die 7.

FIG. 4 shows that when the burring punch 5 is lowered in the burring process, the burring is lowered at the 0 part of the burring punch 5 and the burring is completed. An enlarged view of the product in this case is shown in FIG.

Chamfering and burring can be performed using the above steps.

〔Effect of the invention〕

The present invention has the following effects. In other words, the chamfering process can be incorporated into the press process, and the cutting process itself can be eliminated, eliminating the need for cutting machines and jigs, and eliminating chips, resulting in a significant cost reduction. It can be measured.

Another solution is to press a chamfering punch after burring, but this is affected by the undulations of the burring shape, variations in height, and uneven outside diameter, making it difficult to control the chamfering and deforming parts other than the chamfered part. Although there are drawbacks,
The method of the present invention, in which chamfering is performed before burring and then burring is erected, allows for highly accurate machining.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view before chamfering, Figure 2 is a cross-sectional view during chamfering, Figure 3 is a cross-sectional view before burring, Figure 4 is a cross-sectional view during burring, and Figure 5 is a hole punched with a press. A sectional view of the plate, FIG. 6 is a sectional view after chamfering, and FIG. 7 is a sectional view after burring is completed. A... Chamfered taper part. C...Burring punch flat part. l... Chamfer punch. 2...Beveled die. 5... Burring punch. 7... Burling dice. ill diagram

Claims (1)

[Claims] After drilling a hole in a metal plate by press working, the hole in the metal plate is chamfered using a chamfering punch having a chamfering taper portion and a chamfering die, and then the hole in the metal plate is chamfered using a burring punch having a burring punch having a flat portion and a burring die. A chamfer burring method in which holes in a board are burred using a press.