Method and apparatus for providing a measuring tape with increased cupping
A method of producing a measuring tape may include providing a cupped blade with substantially uniform cupping over a longitudinal length of the cupped blade, applying a stress relief operation to a selected portion of only a convex side of the cupped blade to increase curvature of the cupped blade in the selected portion of the cupped blade where the stress relief operation includes bead blasting the selected portion via a dual nozzle shot peening assembly to define a combined bead blast area that is substantially centered with respect to a longitudinal centerline of the blade, and operably coupling the cupped blade to a reel assembly and providing the cupped blade and reel assembly within a housing to define the measuring tape device.
1. A shot peening assembly for cupping a measuring tape blade, the assembly comprising:
a first nozzle operably coupled to a high pressure air line and a shot line to enable shot entering a pressurized air stream from the high pressure air line to be propelled against a first portion of a convex side of the blade via the first nozzle;
a second nozzle disposed relative to the first nozzle to form a dual nozzle with the first nozzle, the second nozzle being operably coupled to the same or a second instance of the high pressure air line and the shot line to enable shot to be propelled against the convex side of the blade via the second nozzle to define a combined bead blast area at the convex side of the blade,
wherein the combined bead blast area is substantially centered with respect to a longitudinal centerline of the blade.
2. The assembly of claim 1 , wherein the first and second nozzles of the dual nozzle are disposed proximate to each other substantially equidistant from a plane bisecting the blade through an apex of the blade as the blade is transported proximate to the assembly.
3. The assembly of claim 2 , further comprising a plurality of rollers configured to transport the blade proximate to the dual nozzle.
4. The assembly of claim 3 , further comprising at least a second dual nozzle disposed to be separated from the dual nozzle along a length of the blade.
5. The assembly of claim 2 , wherein the first and second nozzles of the dual nozzle are disposed at an angle with respect to the plane.
6. The assembly of claim 2 , wherein the first and second nozzles of the dual nozzle are disposed to propel respective streams of shot in directions parallel to the plane.
7. The assembly of claim 2 , wherein the first and second nozzles of the dual nozzle are disposed to generate overlapping bead blast areas that each traverse the plane.
8. The assembly of claim 2 , wherein the first and second nozzles of the dual nozzle are disposed to generate non-overlapping bead blast areas that meet each other at the plane.
9. The assembly of claim 2 , wherein the first and second nozzles of the dual nozzle are disposed to be separated from each other along a length of the blade such that the first nozzle aims a first bead stream substantially at a left side of the plane and the second nozzle aims a second bead stream substantially at a right side of the plane.
10. The assembly of claim 9 , wherein the first and second nozzles of the dual nozzle are configured to simultaneously apply the first and second bead streams to a same location along a length of the blade.
11. The assembly of claim 9 , wherein the first and second nozzles of the dual nozzle are configured to sequentially apply the first and second bead streams to a same location along a length of the blade.
12. A method of producing a measuring tape device, the method comprising:
providing a cupped blade with substantially uniform cupping over a longitudinal length of the cupped blade;
applying a stress relief operation to a selected portion of only a convex side of the cupped blade to increase curvature of the cupped blade in the selected portion of the cupped blade, the stress relief operation comprising bead blasting the selected portion via a dual nozzle shot peening assembly to define a combined bead blast area that is substantially centered with respect to a longitudinal centerline of the blade; and
operably coupling the cupped blade to a reel assembly and providing the cupped blade and reel assembly within a housing to define the measuring tape device.
13. The method of claim 12 , wherein providing the cupped blade with substantially uniform cupping comprises:
cutting a sheet of material into strips of a desired width;
heating and drawing the strips through a forming machine to generate cupped strips;
cooling the cupped strips; and
chopping the cupped strips to a desired length to define the cupped blade.
14. The method of claim 12 , wherein providing the cupped blade with substantially uniform cupping further comprises tempering the cupped strips prior to chopping the cupped strips.
15. The method of claim 12 , wherein applying the stress relief operation comprises employing shot peening to plastically deform the selected portion via a first nozzle and a second nozzle of the dual nozzle such that a bead stream from each of the first and second nozzles is angled with respect to a plane bisecting a longitudinal centerline of the blade.
16. The method of claim 12 , wherein applying the stress relief operation comprises employing shot peening to plastically deform the selected portion via a first nozzle and a second nozzle of the dual nozzle such that a bead stream from each of the first and second nozzles is parallel with respect to a plane bisecting a longitudinal centerline of the blade.
17. The method of claim 12 , wherein applying the stress relief operation comprises employing shot peening to plastically deform the selected portion via a first nozzle and a second nozzle of the dual nozzle, wherein the first and second nozzles of the dual nozzle are disposed to generate overlapping bead blast areas that each traverse a plane bisecting a longitudinal centerline of the blade.
18. The method of claim 12 , wherein applying the stress relief operation comprises employing shot peening to plastically deform the selected portion via a first nozzle and a second nozzle of the dual nozzle, wherein the first and second nozzles of the dual nozzle are disposed to generate non-overlapping bead blast areas that meet each other at a plane bisecting a longitudinal centerline of the blade.
19. The method of claim 12 , wherein applying the stress relief operation comprises employing shot peening to plastically deform the selected portion via a first nozzle and a second nozzle of the dual nozzle, wherein the first and second nozzles of the dual nozzle are disposed to be separated from each other along a length of the blade such that the first nozzle aims a first bead stream substantially at a left side of a plane bisecting a longitudinal centerline of the blade and the second nozzle aims a second bead stream substantially at a right side of the plane.
20. The method of claim 12 , wherein applying the stress relief operation comprises employing shot peening to plastically deform the selected portion via a first nozzle and a second nozzle of the dual nozzle, wherein the first and second nozzles of the dual nozzle are configured to simultaneously apply the first and second bead streams to a same location along a length of the blade or sequentially apply the first and second bead streams to a same location along a length of the blade.