Laser welded broadhead
A broadhead including parts inseparably connected by laser welding.
This application claims priority to, is a continuation-in-part of, and incorporates by reference U.S. patent application Ser. No. 11/102,939 filed Apr. 11, 2005, which in turn claims priority to U.S. Pat. No. 6,939,258, filed Jun. 28, 2002 (the “'258 Patent”). The '258 Patent claims priority to: (1) U.S. Provisional Patent Application No. 60/354,214, filed Feb. 4, 2002; (2) U.S. Provisional Patent Application No. 60/365,249, filed Mar. 18, 2002; (3) U.S. Pat. No. 6,726,581, filed Aug. 4, 2001 (continuation-in-part), which claimed priority to U.S. Provisional Patent Application No. 60/265,114, filed Jan. 31, 2001, and U.S. Provisional Patent Application No. 60/293,307, filed May 24, 2001; and (4) U.S. Pat. No. 6,605,012, filed Mar. 8, 2002 (continuation-in-part), which claimed priority to U.S. Provisional Patent Application No. 60/273,819, filed Mar. 8, 2001, and U.S. Provisional Patent Application No. 60/286,030, filed Apr. 24, 2001.
TECHNICAL FIELDThe description contained herein generally relates to archery equipment. More particularly, the present invention relates to a broadhead for hunting arrows, having parts permanently joined by a laser weld.
BACKGROUNDTraditionally, archery broadheads are made from multiple pieces that are fitted together. The pieces may include individual blades, a tip, and/or other connecting parts. Traditional broadheads also include a means for connecting the broadhead to an arrow, such as a receptacle designed to fit over the shaft of an arrow, with threads or glue to secure the broadhead to an arrow. However, such broadheads can be expensive to manufacture, and they can become loose, and their parts may even separate, through use or transport.
Prior art broadheads may be relatively complex, usually with many pieces including quite often individual blades that must be joined together like a puzzle.
Accordingly, I have found that it is desirable to provide an improved broadhead.
SUMMARYIn accordance with one embodiment, a broadhead includes a plurality of parts, wherein at least two of the parts are permanently fastened together at a laser welded seam. In various embodiments, the parts may include at least one blade, cap, collar, tip structure, or ferrule. The parts may include a tip structure having at least two blades. In some embodiments, no flux or other filler material has been added to the seam. The seam may be a spot welded, overlapping spot welds, or other seam.
In accordance with an alternate embodiment, a method of manufacturing a broadhead includes arranging multiple components or parts of a broadhead. An energy beam is directed toward contact segments (i.e., locations where at least two components are in contact or close proximity) to weld the components or parts. The components may include blades, a tip structure, a cap structure for receiving a separable ferrule, and/or a collar for receiving a separable ferrule, or a ferrule itself. In embodiments, the energy beam may be a laser, and the method may include focusing the energy beam toward a contact segment using one or more devices such as a focus cell, a lens, and/or a mirror. A focal point of the energy beam may be moved along a contact segment.
Optionally, multiple energy beams may be directed toward a multiple of contact segments simultaneously, wherein each energy beam is directed toward a particular contact segment.
BRIEF DESCRIPTION OF THE DRAWINGS
In the embodiment illustrated in
Returning to
In the embodiment shown in
In an alternate embodiment, as illustrated in
Returning to
In the embodiment of
The frontal point 18 of the blade unit is the first part that will contact a target. Since it is just a point, and since it will receive a tremendous force upon impact, it is preferred that the blade unit be constructed in such a way that it has additional strength. This can be accomplished by grinding and sharpening the razor edges 12 after they are welded together. Grinding and sharpening of the blades may be performed before or after the laser weld occurs.
The welded parts of a broadhead may include blades, ferrules, caps, collars, or any part required to make up the broadhead. The unitary blade unit or broadhead may be made of any metal. For example, the blades, blade unit, other parts or the entire broadhead may be made using carbon steel, aluminum, stainless steel, spring steel, tool steel, or titanium, or a composition including any of the above.
The blade unit and/or broadhead may be made by assembling the blades into a unitary structure. Referring to
This process is performed for each point of intersection, preferably simultaneously with multiple lasers and focus cells such as is shown in
The process of welding broadhead parts together may be performed using a Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) laser device. The Nd:YAG laser may operate in a pulsed mode, continuous mode or both. Other operational characteristics are possible. A laser weld produced by an Nd:YAG laser does not require any filler material or flux, and need not have any direct physical contact with the part that is to be welded. Accordingly, laser welding can yield a blade unit that does not have the increased weight and compositional variability that may result from the introduction of flux into the weld points. However, flux may be used with a laser welding method and still be within the scope of the present invention. Preferably, the laser is operated in a pulse mode with a surface temperature below boiling point to produce a limited weld without deformation of the broadhead parts. Alternatively, the laser welding may be performed using a carbide dioxide (CO2) or other laser that is capable of producing a weld but does not require flux or other filler material, although flux or filler may optionally be used in some embodiments. The weld may be either a spot weld, in which heat transport occurs predominantly by conduction so that melting of the material occurs, thus fusing the material together when it cools. Alternatively, the weld may be a seam weld, produced by a sequence of overlapping spot welds or by the formation of a continuous molten weld pool.
The many features and advantages of the invention are apparent from the detailed specification. Thus, the invention is intended to include all such features and advantages of the invention which fall within the true spirits and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described in the specification, claims, and drawings herein. Accordingly, all appropriate modifications and equivalents may be included within the scope of the invention.
Claims
1. A broadhead comprising:
- a plurality of parts, wherein at least two of the parts are permanently fastened together at a laser welded seam.
2. The broadhead of claim 1 wherein the parts comprise at least one blade.
3. The broadhead of claim 1 wherein the parts comprise a cap.
4. The broadhead of claim 1 wherein the parts comprise a collar.
5. The broadhead of claim 1 wherein the parts comprise a ferrule.
6. The broadhead of claim 1 wherein the parts comprise a tip structure.
7. The broadhead of claim 1 wherein no flux or other filler material has been added to the seam.
8. The broadhead of claim 1 wherein flux or other filler material has been added to the seam.
9. The broadhead of claim 1 wherein the laser welded seam comprises a spot welded seam.
10. The broadhead of claim 1 wherein the laser welded seam comprises overlapping spot welds.
11. A broadhead comprising:
- a plurality of blades;
- wherein at least one of the blades is permanently joined to another part of the broadhead by a laser welded seam.
12. The broadhead of claim 11, wherein the other part is another blade.
13. The broadhead of claim 11 wherein the other part is a cap or collar.
14. The broadhead of claim 11 wherein the other part is a ferrule.
15. A broadhead comprising:
- a first blade;
- at least one other part, wherein the at least one other part is selected from the group consisting of a second blade, a cap, a collar, and a ferrule;
- wherein the blade and the other part are permanently fastened together at a laser welded seam that contains no flux or filler material.
Type: Application
Filed: Sep 23, 2005
Publication Date: Feb 9, 2006
Inventor: Philip Muller (Mercerville, NJ)
Application Number: 11/234,353
International Classification: A63B 65/02 (20060101);