Bandsaw blade and method of manufacturing same

• US 5,249,485 A
• Filed: 12/31/1991
• Issued: 10/05/1993
• Est. Priority Date: 12/31/1991
• Status: Expired due to Term

• Current Assignee: Kapman AB (Snap-On Incorporated)
• Original Assignee: Sandvik AB
• Inventors: Hayden, Robert C. Sr.
• Primary Examiner(s): Yost, Frank T.
• Assistant Examiner(s): Peterson, Kenneth E.
• Application Number:
  US07/814,791
• Time in Patent Office: 644 Days
• Field of Search: 76/112, 76/101.1, 76/115, 76/DIG. 2, 83/835, 83/661
• US Class Current: 76/112
• CPC Class Codes: B23D 61/121 Types of set; Variable teeth, e.g. variable in height or gullet depth; Varying pitch; Details of gullet
• CPC Class Codes: B23D 65/00 Making tools for sawing machines or sawing devices for use in cutting any kind of material
• CPC Class Codes: Y10S 76/02 Case hardening
• CPC Class Codes: Y10T 83/9317 Endless band or belt type

Abstract

A bandsaw blade comprises a plurality of cutting teeth spaced longitudinally apart by gullets. Each tooth includes a steel portion and a carbide tip brazed to a front face of the steel portion. The deepest point of the gullet lies on a curved section having a relatively large radius of curvature, and is spaced longitudinally forwardly of the trailing carbide tip by a relatively large distance. Transversely spaced corners of the gullet bottom are made smoothly rounded by a shot-peening operation.

Claims

1. A method of making a bandsaw blade comprising the steps of:

providing a steel band having a plurality of steel portions spaced longitudinally apart by curved gullets, each gullet including a bottom having transversely spaced corners;

brazing carbide tips onto front faces of said steel portions; and

shot-peening said corners of said gullet bottom prior to said brazing step to hammer said corners into a smoothly rounded shape and prestress the gullet bottom in compression for enhancing the fatigue resistance of the blade.

2. A method according to claim 1, wherein said shot-peening step comprises shot-peening said corners by two stationary shot-peening nozzles oriented obliquely relative to the plane of said blade.

3. A method according to claim 1, wherein said shot-peening step comprises traversing a shot-peening nozzle transversely across said gullet bottom.

4. A method of making a bandsaw blade comprising the steps of:

providing a steel band having a plurality of steel portions spaced longitudinally apart by curved gullets, each gullet including a bottom having transversely spaced corners;

brazing carbide tips onto front face of said steel portions such that;

said steel portions and carbide tips form teeth having a pitch defined by a longitudinal distance between topmost points of successive carbide tips,

each gullet has a depth defined by a distance from said topmost point of a carbide tip trailing such gullet to a deepest point of such gullet, and said deepest point is spaced longitudinally from said topmost point of said trailing carbide tip by a longitudinal distance equal to at least 15% of said pitch;

said deepest point lies on a curved section of a bottom of said gullet defined by a radius of curvature which is larger than said depth, and

said curved section of said gullet bottom extends longitudinally forwardly and rearwardly of said deepest point by longitudinally forward and rearward distances, respectively, each of which being equal to at least 10% of said pitch; and

shot-peening said corners of said gullet bottom prior to said brazing step to hammer said corners into a smoothly rounded shape and pre-stress the gullet bottom in compression for enhancing the fatigue resistance of the blade.

5. A method according to claim 4, wherein said shot-peening step comprises shot-peening said corners by two stationary shot-peening nozzles oriented obliquely relative to the plane of said saw blade.

6. A method according to claim 4, wherein said shot-peening step comprises traversing a shot-peening nozzle transversely across said gullet bottom.