Cutting tool

• US 8,042,442 B2
• Filed: 02/01/2005
• Issued: 10/25/2011
• Est. Priority Date: 08/01/2002
• Status: Expired due to Fees

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Kirschner, Robert, Hemper, Roland
• Primary Examiner(s): Nguyen; Phong H
• Application Number:
  US11/046,790
• Publication Number:
  US 20050188802A1
• Time in Patent Office: 2,457 Days
• Field of Search: 831/28, 83111-124, 831/32, 831/38, 831/39, 831/42, 831/46, 836/84, 836/86, 839/11, 761/071, 761/078
• US Class Current: 83/128
• CPC Class Codes: B21D 37/205 Making cutting tools
• CPC Class Codes: Y10T 83/2133 By resiliently biased ejector
• CPC Class Codes: Y10T 83/9423 Punching tool
• CPC Class Codes: Y10T 83/9452 With tool contour adjusting means

Abstract

A cutting tool, particularly for steel sheet billets, having a cutting blade fastened to a blade holder and a pressure cushion which is arranged on sides of the blade holder and, when the cutting blade penetrates into the material to be punched, is pressed onto the latter in the area of the useful punched part. During the passage of the cutting blade, a high-quality edge of the useful punched part is largely kept free of an interfering burr and elevation formation by the pressure cushion material being displaced radially outward during the punching stroke, such that the cutting blade is acted upon by pressure in the lateral direction under an increasing elastic deflection of the cutting blade edge.

Claims

1. A cutting tool for cutting steel sheet billets, comprising:

a blade holder;

a cutting blade fastened to the blade holder; and

a pressure cushion which is arranged on a blade side of the blade holder and adjacent to a side of the cutting blade,

wherein,

the steel sheet billets are supported by a continuous firm support on a side away from the cutting blade in an area opposite the cutting blade such that when the cutting blade is proceeding through the steel sheet billet, steel sheet billet material cannot flow toward the continuous firm support,

when the cutting blade penetrates into a material to be punched during a punching stroke, the pressure cushion is pressed on a side of the cushion opposite a side facing the material to be punched in an area of a useful punched part, and

the pressure cushion and the cutting blade are arranged such that as the pressure cushion is pressed against the useful punched part, the pressure cushion presses laterally against the cutting blade, such that as the cutting blade proceeds through the material to be punched, the pressure applied by the pressure cushion in a lateral direction causes an increasing elastic deflection of a cutting edge of the cutting blade.

2. Cutting tool according to claim 1, wherein the useful punched part is enclosed by a cutting line of the cutting blade, the pressure cushion is arranged in a cross-sectional interior of the cutting blade, and the latter is elastically expanded by the displaced pressure cushion material in the cutting edge area.

3. Cutting tool according to claim 2, wherein when in a relaxed condition, the pressure cushion is arranged with its punched-material-side face essentially flush with respect to the cutting plane of the cutting blade.

4. Cutting tool according to claim 2, wherein on a side facing away from the pressure cushion, the cutting blade is beveled in the direction of the cutting edge.

5. Cutting tool according to claim 2, wherein the cutting blade has at least one parting line extending to the cutting edge.

6. Cutting tool according to claim 2, wherein the cutting blade consists of flexible band steel.

7. Cutting tool according to claim 6, wherein the band steel consists of a super-high-strength nickel chromium steel of a high elasticity.

8. Cutting tool according to claim 2, wherein the blade holder is provided with variably adjustable cutting blade fastening elements for different cutting geometries.

9. Cutting tool according to claim 2, wherein the pressure cushion consists of an elastomer material.

10. Cutting tool according to claim 1, wherein when in a relaxed condition, the pressure cushion is arranged with its punched-material-side face essentially flush with respect to the cutting plane of the cutting blade.

11. Cutting tool according to claim 1, wherein on a side facing away from the pressure cushion, the cutting blade is beveled in the direction of the cutting edge.

12. Cutting tool according to claim 1, wherein the cutting blade has at least one parting line extending to the cutting edge.

13. Cutting tool according to claim 1, wherein the cutting blade consists of flexible band steel.

14. Cutting tool according to claim 13, wherein the band steel consists of a super-high-strength nickel chromium steel of a high elasticity.

15. Cutting tool according to claim 1, wherein the blade holder is provided with variably adjustable cutting blade fastening elements for different cutting geometries.

16. Cutting tool according to claim 1, wherein the pressure cushion consists of an elastomer material.