Chisels
AssigneeBlack & Decker Inc.
InventorsThomas J. Quinn, David N. Johnson, Florian Probst
Life of this patent
Estimating the term…
Abstract
A chisel includes an elongate shank portion composed of a first steel, and a working end portion composed of a second steel that is different than the first steel. The working end portion is joined to the shank and configured to chisel a workpiece. The joined shank portion and working end portion has been heat treated to cause the first steel of the shank portion to adopt a first microstructure comprising bainite, the second steel of the working end portion to adopt a second microstructure comprising martensite, and the working end portion to have a greater hardness than the shank portion.
Claims20
A chisel comprising:
- an elongate shank portion composed of a first steel, and
- a working end portion joined to the shank portion to form a joined shank portion and working end portion and configured to chisel a workpiece, the working end portion composed of a second steel that is different than the first steel,
- wherein the joined shank portion and working end portion have been heat treated to cause the first steel of the shank portion to adopt a first microstructure comprising bainite, the second steel of the working end portion to adopt a second microstructure comprising martensite, and the working end portion to have a greater hardness than the shank portion.
A process of producing a chisel, the process comprising:
- (a) forming an elongated shank portion from a first steel;
- (b) forming a working end portion configured to chisel a workpiece from a second steel that is different than the first steel;
- (c) joining the shank portion to the working end portion;
- (d) heat treating the joined shank portion and working end portion, thereby causing the first steel of the shank portion to adopt a microstructure comprising bainite, the second steel of the working end portion to adopt a microstructure comprising martensite, and the working end portion to have a greater hardness than the shank portion.
Dependencies are inferred from the claim text.