DE102007047836A1 - Method for producing a burr-free cut surface and apparatus for carrying out the method - Google Patents

Abstract

The invention relates to a method for producing a burr-free cut surface when punching or cutting a stamped material (4), which has a material thickness (s). It is proposed that first a first punching stroke be carried out by punching (cutting) in a first direction (H1) and ansciden) in a second, the first opposite direction (H2).

Description

The The invention relates to a method for producing a burr-free cut surface according to the preamble of claim 1 and an apparatus to carry out the method according to the preamble of Claim 2.

At the Punching or cutting sheet metal occurs at the cut surface on the one hand a Kanteneinzug and on the other hand on the edge feed on the opposite side of the sheet a ridge. The ridge must be removed by rework, including additional Tools or procedures are needed. Through the edge feed is the height of the cut surface compared to Material thickness of the sheet is reduced, resulting in functional surfaces not wanted. It is therefore known to cut stamped parts, d. H. in an additional operation with an additional Machining tool by cutting a chip from the cut surface is lifted so that both the burr and the edge feed are eliminated.

By the CH 665 367 A5 was a method for fine cutting a workpiece known, which is edited after fine cutting by trimming, so that the resulting during fine cutting edge indentation and burr are removed. During the trimming process, the trimming tool is moved in the direction of the edge indentation. Thus, a reversal of the cutting direction takes place in this machining process.

It Object of the present invention, in a method of the type mentioned a burr-free cut surface as possible to produce, without rework. It is also the task of Invention, a suitable device for implementation of the method.

The The object of the invention is first by the features of claim 1. According to the invention provided that the punching material in two in opposite Punched and cut in successive punching directions or finely cut, and that while punching (Edge indentations) produced on both sides of the punching material become. Thus, the advantage of a largely burr-free cut surface on Punching material achieved. The first punching stroke results the top of the punching material a first Kanteneinzug and through results in the second in the opposite direction punching stroke at the bottom of the punching material, a second edge indentation, so that the sheared surface (cut surface) the punching material is burr-free. A rework with additional Tools is not required.

Of the first punching stroke takes place over a stroke length, which about half the material thickness of the punching material corresponds. The second punching stroke takes place in the opposite direction then the complete shearing of the punching material.

The The object of the invention is also achieved by a device having the features of claim 2. According to the invention the device has a first die with a guide part, between which the punching material is received, and a first Stamp with a counterholder, between which the stamping material is located. In the manufacture of the first punching device in a first direction, z. B. down, the first die acts as a die and the first Stamp as a cutting punch, d. H. he cuts with his cutting edge in the punching material, which passes through the die and the guide member is held.

In Advantageous embodiment of the device is the guide part for the second punching as a second die and the Counterholder designed as a second cutting punch. At the second time Punching (in the opposite direction to the first) affects the Counterhold so as a second cutting punch, which from the opposite laws Direction cuts into the punching material, which by the second Die-acting guide part is held. The advantage the device according to the invention is to see that for making a burr-free cut surface only a tool and thus only a Werkstückeinspannung required are. A re-clamping of the punched (cut) Workpiece and / or a subsequent processing in a second Tool level for rework can thus omitted.

One Embodiment of the invention is in the drawing and will be described in more detail below.

The single figure shows a simplified representation of a device 1 for carrying out the method according to the invention. The device 1 has a first die 2 and a leadership part 3 on, which also as a second template 3 acts. Between the first die 2 and leadership part 3 is a stamping material 4 , a sheet of strength s, inserted. The device 1 further includes a first stamp 5 and a backstop 6 , which also acts as a second stamp. Between first stamp 5 and first template 2 as well as between counterholds 6 and leadership part 3 a cutting gap a is present. The first stamp 5 has a cutting edge 5a and the second stamp 6 has a cutting edge 6a on. The punching material 4 is between die 2 and leadership part 3 clamped in the direction of arrow H. Preferably, this can also be done by means not shown ring zacken, which are known from fineblanking, which is explained in the above-mentioned document to the prior art.

The procedure is as follows: The stamp 5 (Cutting punch) is first moved down in the direction of the arrow H1 until its cutting edge 5a on the punching material 4 meets. It then takes a first punching stroke in the direction of the arrow H1 approximately to half the material thickness of the punching material 4 ie to s / 2. In the downward stroke movement (corresponding to arrow H1) is the anvil 6 at the bottom of the punching material 4 and comes with the movement of the stamp 5 carried. After completion of the first punching stroke by the amount s / 2 in the direction H1, the punching direction is reversed, ie the anvil 6 now takes on the function of a second cutting punch, penetrates with its cutting edge 6a in the bottom of the punching material 4 and moves in the direction of the arrow H2 upwards until the punching material 4 completely separated. The two punching strokes, on the one hand in the direction H1 and on the other hand in the direction H2, produce edge indentations (punching indents) on the top and bottom of the stamped material so that a not shown burr-free cut surface (cut surface without punching burr) results when the stamped material has been sheared off. This eliminates a rework to remove a ridge.

As already indicated, the punching or cutting process as Fineblanking be performed - like him is known from the prior art. This results in an improved, d. H. largely crack-free cut surface.

1

punching device

2

first die

3

guide part (second template)

4

Die-cut

5

first stamp

5a

cutting edge

6

backstop (second stamp)

6a

cutting edge

a

cutting gap

H1

first punching direction

H2

second punching direction

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - CH 665367 A5 [0003]

Claims (4)

Method for producing a burr-free cut surface when punching or cutting a stamped material ( 4 ), which has a material thickness (s), wherein first a first punching stroke by punching (cutting) in a first direction (H1) and then a second punching stroke by punching (cutting) in a second, the first opposite direction (H2) are performed , whereby at the top and bottom of the punching material ( 4 ) Are formed, characterized in that the first punching stroke corresponds to about half the material thickness (s / 2) and the punching material ( 4 ) is sheared off during the second punching stroke. Device for carrying out the method according to claim 1, characterized by a first die ( 2 ) with a guide part ( 3 ) as well as a first stamp ( 5 ) with a counterholder ( 6 ). Apparatus according to claim 2, characterized in that the guide part ( 3 ) is designed as a second die for the second punching stroke. Device according to claim 2 or 3, characterized in that the counter-holder ( 6 ) is designed as a second punch for the second punching stroke.