US 20060143765 A1
A method of making a face mask including the steps of providing a plurality of lengths of Grade 2, commercially pure titanium wire, having a diameter of from about 0.21 to about 0.24 inches; forming each length at room temperature to a desired bend angle by bending the member at room temperature using rotary bending apparatus to a first bend angle that is from about 1.25 to about 1.35 times greater than the desired bend angle; and welding each of the thus formed lengths to at least one other of the lengths in an ambient, oxygen containing environment.
7. A helmet, comprising a helmet shell and a face mask attachable to the shell, the face mask comprising: plurality of titanium wire members positioned in a desired configuration and interconnected to one another by a plurality of welds, each weld being a resistance spot weld formed in an ambient, oxygen containing environment and having suitable weld strength such that the face mask complies with the Standard Method of Impact and Performance Requirements of the National Operating Committee on Standards for Athletic Equipment (Jul. 14, 1987, Revised Jul. 10, 1990).
8. The helmet of
9. The helmet of
This is a divisional application of pending U.S. application Ser. No. 09/514,624, entitled TITANIUM WIRE FACE GUARD AND METHOD FOR MAKING SAME, filed Feb. 28, 2000.
This invention relates generally to face guards for sporting helmets.
More particularly, this invention relates to a method for manufacturing face guard for football helmets manufactured using titanium wire.
The invention further relates to a method for producing face guards made of titanium wire in an manner that is uncomplicated and cost effective.
The present invention is directed to a method of making a face mask including the steps of providing a plurality of lengths of Grade 2, commercially pure titanium wire, having a diameter of from about 0.21 to about 0.24 inches; forming each length at room temperature using rotary bending apparatus to a desired bend angle by bending the member at room temperature to a first bend angle that is from about 1.25 to about 1.35 times greater than the desired bend angle; and welding each of the thus formed lengths to at least one other of the lengths in an ambient, oxygen containing environment.
The invention advantageously enables manufacture of titanium face masks in a cost-effective and uncomplicated manner. Face masks made in accordance with the invention are lighter in weight than conventional steel-based face masks and offer numerous advantages to conventional face masks.
Further advantages of the invention will become apparent by reference to the detailed description of preferred embodiments when considered in conjunction with the figures, which are not to scale, wherein like reference numbers, indicate like elements through the several views, and wherein;
With reference to the drawing figures, the invention relates to a face guard or mask 10 that is particularly suitable for use with a sporting helmet, such as a football helmet 12 (
Each of the members 14-22 is preferably provided by a length of Grade 2, commercially pure titanium wire, having a diameter of about 0.224 inches.
In the manufacture of the members 14-22, lengths of wire material are provided by sharing as set forth in TABLE 1:
It will be understood that the foregoing lengths are for a preferred embodiment only and that the wires may be of various other lengths depending on the desired configuration and size of the mask.
The members are next formed, preferably at room temperature (e.g., about 50 to about 80° F.), to impart a desired shape to each of the wires 24-32, the desired configuration preferably being that shown for the members 14-22, respectively.
In this regard, and with reference to
As will be noted, ends 24 a and 24 b of the wire 24 are substantially outside of the bend imparted as shown in
Returning to the initial manipulation of the wire 24 to achieve the desired formed degree of bend, it has been experienced that a formed degree of bend of 159 degrees for the member 14 may be achieved using a die having a radius of about 3.195 inches and overbending the wire 24 to a degree of bend A′, shown in phantom, of about 206 degrees. Thus, the wire 24 must be significantly bent past the desired formed degree of bend to impart the desired bend. The foregoing described bend and the similar bends described below in connection with
Next, additional bends are preferably imparted to the ends 24 a and 24 b in a similar manner of overbending. To provide the preferred configuration for the member 24, the ends 24 a and 24 b are each preferably bent to achieve a formed degree of bend of about 46 degrees, represented by the angle B, with an inside bend radius (R) of about 0.75 inches. To achieve this, the ends 24 a and 24 b are subjected to overbending of about 53 degrees (
The members 16-22 are formed from the wires 26-32 in a similar manner. For example, with reference to
It has been experienced that a formed degree of bend of 164 degrees for the member 16 may be achieved using a die having a radius of about 2.977 inches and overbending the wire 26 to a degree of bend A′, shown in phantom, of about 214 degrees.
Ends 26 a and 26 b (
A second portion of the ends 26 a and 26 b having a length of about 1.25 inches is similarly formed to achieve a formed degree of bend of about 74 degrees, represented by the angle B′, with an inside bend radius (R′) of about 0.25 inches. To achieve this, the first portion is subjected to overbending of about 79 degrees (
As shown in
It has been experienced that a formed degree of bend of 164 degrees for the member 18 may be achieved using a die having a radius of about 2.977 inches and overbending the wire 28 to a degree of bend A′, shown in phantom, of about 213 degrees.
Ends 28 a and 28 b (
As shown in
It has been experienced that a formed degree of bend of 164 degrees for the member 20 may be achieved using a die having a radius of about 2.857 inches and overbending the wire 28 to a degree of bend A′, shown in phantom, of about 200 degrees.
Ends 30 a and 30 b (
Wire 32 (
The foregoing information concerning the formation of the members 14-22 from the wires 24-32 is provided below in Tables 2 and 3. Table 2 relates to the primary bends in the members (
As will be noted from Table 2, for bends formed using the described rotary bending apparatus, the ratio of the degree of bend applied to that of the formed bend is generally between about 1.25 and 1.35 and, is most preferably between about 1.28 and 1.30.
As will be noted frown Table 3, for bends formed using the described press bending apparatus, the ratio of the degree of bend applied to that of the formed bend is generally between about 1.05 and 1.16 and, is most preferably between about 1.07 and 1.15.
The formed members 14-22 are thereafter arranged in the desired configuration and held in position and squeezed against one another, as by a clamp fixture, for welding. Welding is accomplished as by spot welding at each weld location W using a press-type projection welder of the type available from Standard Resistance Welding Company of Winston, Ga. A preferred welder is A 50 KVA, 460 Volt, single phase welder available from Standard Resistance Welder Company.
The transformer setting or TAP setting for the welder is preferably set at about 7, with the welder control settings set forth in TABLE 4:
It is surprising that welds of suitable strength to achieve a face mask compliant with the relevant standards of the National Operating Committee on Standards for Athletic Equipment (NOCSAE) such as the NOCSAE Standard Method of Impact and Performance Requirements for Football Faceguards were achievable. It is known that titanium is highly reactive and would not be expected to provide suitable weld strength when welded in a reactive environment, such as in the presence of oxygen. As will be appreciated, the ability to achieve suitable weld strength in this manner achieves considerable cost savings as compared to welding in a non-reactive environment.
For the purposes of the invention, it was observed that the settings set forth in Table 3 were important to achieving suitable weld strength.
After welding, the guard is removed from the fixture and all wire terminations ground using silicon carbide sandpaper to a full radius to avoid sharp ends. The face guard is thereafter cleaned, primed with a bonding agent, such as a lacquer basic phenolic bonding agent, and coated with vinyl to a thickness of from about 0.02 to about 0.09 inches.
When used for football helmets, face guards in accordance with the invention should be tested for compliance with the afore-mentioned NOCSAE standard. Likewise, compliance with any other relevant standards or criteria should be determined dependent upon the intended use of the face guard.
A face guard constructed as described herein was observed to have a weight less than that of conventional steel wire and steel tubing face guards. For example, a similarly configured face guard made from steel wire of the same diameter (0.225 inches) would have a weight of over about 16 ounces, uncoated, and one made from steel tubing having an outside diameter of about 0.25 inches (i.d. 0.160 inches) would have a weight of at least about 11 ounces, uncoated. The foregoing described face guard of the invention has a weight of about 9 ounces, uncoated.
It has also been observed that face guards made in accordance with the invention are more resistant to corrosion than conventional steel and steel tubing face guards.
The invention advances the art by enabling the production of face guards made of titanium wire which have desirable qualities and which may be produced in an economical and uncomplicated manner. It has been stated in the prior art that face guards could be made using titanium containing materials. For example, U.S. Pat. No. 5,713,082 states that the face mask thereof “is usually cast with thin cross sections as a single piece and hardened using high strength alloys (e.g. titanium, 4140 steel, 4140 stainless steel, etc.).” Col. 5, lines 2-4. U.S. Pat. No. 5,806,088 describes a face guard of metal tubes construction, with a metal tube 22 thereof made of steel, or of other metals or metal alloys (metal mixtures) such as aluminum, carbon, cobalt, chromium, iron, nickel, tin titanium and zinc. Co, 4, lines 7-11. It is believed that prior attempts to manufacture face guards using titanium containing materials have resulted in face guards that are unsuitable for their intended purpose and/or of such expense so at to be commercially unfeasible.
It has unexpectedly been discovered that face guards of desirable characteristics may be economically produced in accordance with the invention. For example, in accordance with the invention, it has been discovered that face guards having desirable characteristics may be manufactured using Grade 2, commercially pure titanium wire, having a diameter of from about 0.21 to about 0.24 inches, most preferably from about 0.224 to about 0.225 inches. For the purposes of the invention, it was observed that the selection of this particular material in the afore-mentioned diameter range was important to achieving the purposes of the invention.
The foregoing description of certain exemplary embodiments of the present invention has been provided for purposes of illustration only, and it is understood that numerous modifications or alterations may be made in and to the illustrated embodiments without departing from the spirit and scope of the invention as defined in the following claims.