Method of manufacturing bent razor blades

Patent metadata

Field	Value
Publication number	US-10625331-B2
Application number	US-201715784453-A
Country	US
Kind code	B2
Filing date	Oct 16, 2017
Priority date	Nov 7, 2016
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

A method of manufacturing a razor blade by providing a razor blank strip having an edge. The razor blank strip is hardened to a hardness greater than 600HV. A pre-bending zone that is spaced apart from an edge of the razor blank is melted with a laser beam. The pre-bending zone is cooled after melting to form a re-solidification portion. The razor blank strip is segmented into individual blades. The individual blades are bent in the pre-bending zone.

First claim

What is claimed is:

1. A method of manufacturing a plurality of razor blades comprising:
providing razor blank strip having an edge;
hardening the razor blank strip to a hardness greater than 600 HV;
melting a pre-bending zone of the razor blank strip that is spaced apart from the edge with a laser beam;
cooling the pre-bending zone after said melting to form a re-solidified portion;
segmenting the razor blank strip into individual blades; and
bending the individual blades in the pre-bending zone to form a bent portion.

2. The method of claim 1 further comprising applying one or more coatings to the individual blades prior to bending.

3. The method of claim 1 further comprising tensioning the strip of razor blanks during said melting and said cooling.

4. The method of claim 1 wherein a surface temperature of the pre-bending zone is at ambient temperature during said bending.

5. The method of claim 1 wherein the laser beam has a width of 0.01 mm to 0.10 mm.

6. The method of claim 1 wherein the laser beam is applied about 0.5 mm to about 1.2 mm from the edge of the razor blank.

7. The method of claim 1 wherein melting and said cooling comprises removing scratches and surface imperfections in the pre-bending zone less than 0.020 mm deep.

8. The method of claim 1 wherein said melting comprises decreasing a hardness of the pre-bending zone to 300 HV to 500 HV.

9. The method of claim 1 wherein said melting comprises melting the pre-bending zone to a depth less than 35% of a thickness of the blank.

10. The method of claim 1 wherein said melting is performed in the presence of an argon, helium, or nitrogen gas.

11. The method of claim 1 further comprising inspecting the pre-bending zone for scratches prior to said melting.

12. A method of manufacturing a plurality of razor blades comprising:
providing razor blank strip having an edge;
hardening the razor blank strip to a hardness greater than 600 HV;
melting a pre-bending zone of the razor blank strip that is spaced apart from the edge with a laser beam;
cooling the pre-bending zone after said melting to form a re-solidified portion;
tensioning the strip of razor blanks during said melting and said cooling;
segmenting the razor blank strip into individual blades; and
bending the individual blades in pre-bending zone, wherein said melting comprises heating the pre-bending zone with the laser beam to a temperature greater than 1100 C.

13. The method of claim 12 wherein the laser beam is applied about 0.5 mm to about 1.2 mm from the edge of the razor blank.

Assignees

• Gillette Co Llc

Inventors

• Han Wei
• Xu Ming Laura
• Maziarz John Lawrence

Classifications

• B26B21/222

  with the blades moulded into, or attached to, a changeable unit (B26B21/4006 takes precedence) · CPC title

• B26B21/06

  Safety razors with fixed blade, e.g. with moulded-in blade · CPC title

• B21D53/645 Primary

  safety razor blades · CPC title

• B26B21/4068

  Mounting devices; Manufacture of razors or cartridges (B26B21/528 takes precedence) · CPC title

• B26B21/565 Primary

  Bent razor blades; Razor blades with bent carriers · CPC title