U.S. patent number 3,910,578 [Application Number 05/446,668] was granted by the patent office on 1975-10-07 for lacrosse stick.
Invention is credited to William H. Brine, Jr..
United States Patent |
3,910,578 |
Brine, Jr. |
October 7, 1975 |
Lacrosse stick
Abstract
A combination of polymeric resins, in amounts specifically
chosen with reference to a required balancing of physical
properties, is injection molded to provide an improved laminate
body for use in athletic equipment of the class employed in playing
games wherein a propelled object is moved about and the laminate
body is subjected to high impact stress. Typical of an adaptation
of the laminate body for such athletic equipment is its use in
molding a racquet frame for a lacrosse stick. In this application,
representative of several such applications, an extremely tough,
thin outer skin of very high impact resistance encloses a
relatively low density foamed structure capable of imparting a
pronounced degree of rigidity throughout the laminate body. Thus
there is realized a low cost, light weight lacrosse stick of
unusual durability and excellent handling characteristics, and the
racquet head is not readily deformable by normal player pressure.
The molded structure further includes a reinforced head section in
which lacing strings are protectively contained and prevented from
tearing out, and double walls joined to the reinforced head are
formed of a j-shaped cross sectional configuration which provides
for improved handling of a lacrosse ball. Replacement of the
lacrosse stick handle is facilitated by fastening means located in
a recessed position which affords convenient accessibility.
Inventors: |
Brine, Jr.; William H. (Weston,
MA) |
Family
ID: |
26942896 |
Appl.
No.: |
05/446,668 |
Filed: |
February 28, 1974 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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253061 |
May 15, 1972 |
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Current U.S.
Class: |
473/513;
264/DIG.17; 264/DIG.83; 264/45.5; 273/DIG.7; 264/DIG.14;
264/DIG.18; 273/DIG.6 |
Current CPC
Class: |
A63B
49/02 (20130101); A63B 59/20 (20151001); Y10S
273/07 (20130101); Y10S 264/14 (20130101); Y10S
264/17 (20130101); Y10S 273/06 (20130101); A63B
2102/14 (20151001); Y10S 264/83 (20130101); Y10S
264/18 (20130101) |
Current International
Class: |
A63B
59/00 (20060101); A63B 59/02 (20060101); A63B
059/02 () |
Field of
Search: |
;273/96D,73F,73C,82R,96R
;124/5 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
The Sporting Goods Dealer, Dec. 1971, p. 140..
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Primary Examiner: Pinkham; Richard C.
Assistant Examiner: Siskind; Marvin
Attorney, Agent or Firm: Hamilton; Munroe H.
Claims
I claim:
1. A lacrosse stick comprising a closed frame having a throat
portion, a handle attached to the frame adjacent to the throat
portion, a net supported between the sides of the frame and having
a ball-containing pocket extending forwardly of the throat portion
of the frame, said frame including a transversely disposed head
portion and a pair of side wall portions extending between the head
portion of the said throat portion, and each of said side walls
being shaped to provide a cross section in the form of an inverted
J, thereby to furnish an upper curved ball-trapping edge and lower
relatively straight pocket guiding surfaces.
2. A structure according to claim 1 wherein said transversely
disposed head portion is of a generally dish-shaped cross section
and presents an inwardly inclined upper surface along which a
lacrosse ball may be scooped up and guided into the net and the
underside of said head portion is formed with an intermediately
located reinforced rib portion and a relieved surface extending
inwardly therefrom to constitute a lacing protective recess.
3. A structure according to claim 1 wherein said frame is recessed
to form a handle aperture extending rearwardly from the throat
portion and fastening means are transversely located through the
bottom of the frame and engage the handle.
4. A structure according to claim 3 in which one side of the throat
portion is recessed to define a fastening surface through which the
said fastening is driven.
Description
This invention relates to a novel laminate body for use in athletic
equipment of the class employed in playing games wherein a
propelled object is moved about and the laminate body is subjected
to high impact stress.
The extremely rough playing conditions usually occurring during a
game of lacrosse results in lacrosse racquet frames made of wood
being subject to frequent breaking, deformation, or other damage,
and various proposals have been made to strengthen the lacrosse
racquet frames and render them more satisfactory in use. One such
proposal has been to replace the open or hooked frame arrangement
earlier used with a closed frame of wood or other material as
disclosed in U.S. Pat. No. 2,142,527. Another proposal has been to
substitute a plastic material for wood and to cast liquid
elastomers such as a urethane elastomer in a desired structural
form as has been more recently disclosed in U.S. Pat. No.
3,507,495.
However, in addition to the problem of rough usage to which all
lacrosse sticks and their racquet frames are subjected, there is
further imposed the necessity for containing net lacing without
tearing out and for maintaining the construction of the lacrosse
stick within dimensional limits required by official lacrosse rules
as made by National Lacrosse Rule Committees. For example, the
transversely disposed section of the lacrosse racquet frame,
commonly referred to as the "head" is required to have an inside
measurement of between 7 inches and 12 inches.
The double wall sections of the racquet, recently declared legal by
the Lacrosse Rules Committee, is required to be of a length of
approximately 18 inches from the right angle end of the head to the
handle. In addition, the wall sections shall not be over 2 inches
in height. The rules also specify that the net or pocket of
stringing must have a pocket sag such that the top surface of a
lacrosse ball placed in the pocket will not drop below the bottom
edge of the wall and the ball itself must be of a white or orange
rubber, having a circumference of between 7 3/4 inches and 8
inches, a weight of from 5 ounces to 5 1/2 ounces, and which
bounces, when dropped on a hardwood floor, from a height of 72
inches, a distance of from 45 inches to 49 inches.
Because of these limiting conditions, it is very difficult to find
in any one material all of the properties required for a lacrosse
stick, and there continues to be a need for a more satisfactory
lacrosse construction which can be made within the confines of the
specifications noted, and yet provide a maximum of strength,
playability and wear resistance.
It is a chief object of the invention to cope with the problem
indicated and to provide an improved lacrosse stick construction
wherein several materials are combined and injection molded to form
a lacrosse stick which fully complies with Rule Comittee
requirements and in which there is realized to a maximum degree a
combination of light weight, rigidity without brittleness and a
high degree of resistance to deformation from player pressure.
It is also an object of the invention to devise a structural
configuration in which the head of the lacrosse stick is reinforced
in a novel manner such that not only is the head strengthened, but
the stringing which is passed through the head portion is
protectively contained in a desirable manner.
Still another object is to provide a double wall type lacrosse
stick in which the wall members have an inverted J configuration
which allows the ball to be trapped in the pocket and yet as the
pocket is broken in or stretched, the ball is not subject to
deflection by a lower ridge portion such as would be the case with
the bottom edge on a concaved surface.
Still another object is to devise a fastening arrangement for
replacement of lacrosse stick handles in a convenient and rapid
manner.
The nature of the invention and its other objects and novel
features will be more fully understood and appreciated from the
following description of a preferred embodiment of the invention
selected for purposes of illustration and shown in the accompanying
drawings, in which:
FIG. 1 is a plan view of a lacrosse stick racquet frame with a
handle portion of the stick being indicated fragmentarily;
FIG. 2 is a side elevational view of the lacrosse stick shown in
FIG. 1;
FIG. 3 is a cross section taken on the line 3--3 of FIG. 1;
FIG. 4 is a cross section taken on the line 4--4 of FIG. 1;
FIG. 5 is an enlarged detail section of a portion of the racquet
further indicating a reinforcing rib and recessed lacing
surface;
FIG. 6 is a detail cross sectional view of a modified handle
mounting, and
FIG. 7 is a cross section taken on the line 7--7 of FIG. 6.
Having in mind the problems and requirements inherent in the
construction of a lacrosse stick, as noted above, I have conceived
of a composite polymer structure in which two different polymers of
thermoplastic type are combined together with stiffening fibers, a
blowing agent, and a filler, to provide a foamed laminate body. A
basic inventive concept is to control the components in such a way
as to obtain a balanced combination of extreme toughness,
pronounced rigidity, and resistance to breaking without
brittleness, and this I find may be accomplished by utilizing a
proper polymer mix, limiting the degree of foaming and regulating
the amount of fiber stiffening induced.
In accordance with the invention, I provide a lacrosse stick
racquet frame consisting in a laminate body having a tough stress
crack resistant outer skin which is formed of the components noted.
Associated with this tough outer skin is a foamed inner mass
consisting in an internally stiffened cellular structure which
functions to rigidly suport the tough outer skin against
deformation forces within limits capable of being controlled to
permit retention of a high degree of outer skin toughness and
rigidity and yet avoiding risk of brittleness by reason the very
small degree of yieldability permitted by the cellular structure
under bending stresses.
In thus supporting a tough outer skin with an internally stiffened
cellular structure, I find that I may advantageously employ a
thermoplastic polymer referred to as an ionomer. An ionomer may be
defined as a polymer consisting of an alphaolefin type copolymer
containing ionized carboxylic acid groups and is characterized by
an unusually high melt strength in a foamed structure. I may also
combine with the ionomer polymer a modifying polymer consisting in
a nylon polymer such as Ultramid, B-3 Natural, manufactured by Basf
Wyandotte Company, and this polymer provides additional toughening
and stiffening properties in the laminate body.
I have further determined that by melting the two polymers together
and at the same time combining stiffening fibers such as glass, and
a blowing agent such as NaHCo.sub.3 in carefully controlled
amounts, I may thereafter cool or chill the melted mass while
contained within desired molding surfaces to obtain a tough outer
skin which is free from voids, and an internally stiffened cellular
structure which has very small uniformly sized voids.
By controlling the amounts of the modifying polymer stiffening
fibers and blowing agent in accordance with predetermined stresses
or deformation forces, a material of suitable toughness, rigidity
and freedom from brittleness is realized, well suited to use in a
lacrosse stick as well as other athletic equipment including such
items as shoulder pads, knee pads, field hockey sticks, bats, and
the like.
As illustrative of one desirable procedure for making the composite
plastic structure disclosed above, I may therefore carry out steps
which include bringing together in a confined space a mixture of an
ionomer polymer, a modifying polymer, a quantity of stiffening
fibers and a blowing agent, heating the mixture to provide a melted
laminate body wherein voids are formed internally by the blowing
agent, chilling the laminate body to form a thin outer skin which
is free from voids and controlling the quantity of modifying
polymers, stiffener fibers and blowing agent, combined with the
ionomer polymer to form an outer skin having a tough stress crack
resistant surface, and to provide an internally stiffened cellular
structure for rigidly supporting the tough outer skin against
deformation forces to which athletic equipment of the class
above-indicated may be exposed.
As an example of specific materials for use in making a lacrosse
racquet frame, I may employ an ionomer polymer such as Surlyn A,
manufactured by the E. I. Dupont de Nemours Co., Inc. of
Wilmington, Delaware. With the Surlyn, may be combined a nylon such
as Ultramid, B-3 Natural, manufactured by Basf Wyandotte Co., and
having a common melting point range with Surlyn A of from
400.degree. to 450.degree. F. A suitable stiffening fiber may
consist of glass fiber, as well as fibers such as asbestos fibers
and titanium fibers.
It should be observed that in using stiffening fibers, care must be
exercised in not employing a quantity which will result in
brittleness relative to the impact resistance required in a
lacrosse racquet frame. I have found that for some sizes of
lacrosse sticks such as those used by offensive lacrosse players, I
must limit the quantity of glass fibers within a percentage range
by weight from about 5 percent up to about 10 percent of the total
mixture. This range I further find may vary slightly when larger
sizes of lacrosse sticks are employed, for instance, lacrosse stick
frames used by defensive players, and particularly goalies, where
the percentage of glass fibers can be increased upwardly by a small
degree but not exceeding 15 percent by weight of the total
mixture.
Similarly, I have determined that the blowing agent must be limited
quite sharply to maintain a suitable degree of rigidity in the foam
structure without causing excessive brittleness and in this
respect, having regard for the brittleness factor in relation to a
lacrosse frame, I find that the percentage of blowing agent must be
held within a range of 1 percent to 3 percent.
One desirable formulation for a smaller size of lacrosse stick in
specific quantities may, for example, be as follows: 67 percent
Surlyn A, 10 percent glass fiber, 20 percent Ultramid, 2 percent
filler titanium dioxide, and 1 percent blowing agent
NaHCo.sub.3.
Referring to the drawings, FIGS. 1 and 2 illustrate a lacrosse
stick made from a foamed laminate material of the type above
disclosed. As shown therein, numeral 2 denotes a lacrosse stick
handle, usually of wood, at one end of which is supported a
lacrosse racquet frame made up of a throat portion 4, a head
portion generally denoted by arrow 6, and a pair of spaced side
wall portions 8 and 10 extending between the head portion and the
throat in converging relationship. Supported within the frame
described is a net 12 consisting of interwoven lacing of raw hide
or other material, and having formed therein a ball-receiving
pocket 14 located adjacent to the throat portion 4, as susggested
in FIG. 1.
As earlier described, the entire laminate frame is preferably made
by an injection molding operation utilizing suitable forming
surfaces, as shown, to provide the desired shape indicated in the
drawings, and the molded material, for example, having a
formulation such as that specified above, is heated in a
temperature of from 400.degree. to 450.degree. F. Thereafter, the
molded surface is chilled or cooled to provide throughout the
racquet frame a composite body which includes a thin outer skin,
denoted in the drawings by numeral 16, best shown in FIGS. 4 and 5,
and an internally stiffened cellular structure 18 which is also
indicated in FIGS. 4 and 5 and is characterized by voids of a
relatively minute uniformly-shaped size.
The racquet frame thus constructed is of a relatively light weight
and is, more importantly, of a pronounced rigidity such that it is
capable of resisting deformation by pressures normally exerted by
lacrosse players and can only be deformed by being subjected to
unusually heavy bending forces such as are not ordinarily encounted
in lacrosse play.
It is again pointed out that the internally stiffened cellular
structure 18, with its very small and uniform void composition
functions to help provide a necessary rigidity in the frame. Yet by
being yieldable to a very slight degree because of the foamed
composition, the cellular structure prevents brittleness and serves
to resist breaking under the impact forces usually exerted in
lacrosse play.
It should also be understood that the extreme toughness of the
outer skin 16 not only resists cracking or breaking when subjected
to high impact forces, but also is capable of defining lacing holes
in the frame such as has been indicated in FIG. 2 of the drawings
at 10a, 10b, 10c and 10d, of a high tear resistant nature. It will
be understood that sudden impact of a solid lacrosse ball against
the lacing may impose quite heavy tearing stress, and the
combination of reinforced cellular structure and outer toughened
skin, has been designed in the present invention to withstand such
stresses.
In my improved lacrosse stick construction shown in the drawings, I
have also devised structural improvements in the racquet frame
itself and these structural improvements are introduced at the head
portion, also the side walls and the throat.
Attention is directed to FIG. 4, for example, where I have
illustrated specially formed inner side wall surfaces 20 and 22,
which are especially molded in the shape of an inverted J to
provide upper curved ball trapping portions 20a and 22a, and these
ball trapping portions merge with lower substantially straight ball
releasing surfaces 20b and 22b. In shaping the upper inverted
J-shaped surfaces, I have also formed these surfaces so as to
provide an arc of curvature which corresponds to the arc of
curvature of a standard lacrosse ball, earlier specified. It is
pointed out that by means of this arrangement, the upper inverted J
surfaces 20a and 22a may, at certain points in a ball trapping
operation, be fully in contact with the peripheral surface of the
lacrosse ball when it is trapped in the pocket 14 of the net 12.
There may thus be realized better ball control by the lacrosse
player.
In addition, the frame structure shown in FIGS. 1, 2 3 and 5 has
its head portion 6 specially constructed with a reinforcing rib
part 6a which is located intermediately of inner and outer edges of
the head. This rib portion 6a functions to impart a substantially
increased rigidity in the head, resulting in better durability and
playing characteristics at points where a great deal of bending
stresses are encountered in lacrosse play.
In conjunction with the reinforcing rib 6a, I have also provided a
relieved under surface 6b which extends inwardly of the head
portion of the frame to define a recessed net lacing surface
through which laces may be passed and contained in a protected
relationship such that when the frame is slid along the ground in
scooping up a ball, the laces are protected against abrasion and
wear such as may normally take place in a conventional frame.
At the opposite end of the frame, the throad portion 4 has been
redesigned to form a handle socket 2a into which the handle 2 may
be inserted and detachably secured in place by a screw fastening as
24, and the underside of the throat is relieved to contain the
fastening head in a conveniently recessed manner. This arrangement
provides for rapid and simple replacement of a broken handle by a
player, and the extended socket functions to retain the handle end
in a solidly secured manner.
* * * * *