[0001] This invention relates to a golf club for use in the game of golf, comprising a shank
provided at one end with a striking member made of laminated wood elevated in specific
gravity by compression. The invention further relates to a striking member for a golf
club.
[0002] The striking member often comprises a head with a striking face and a neck, through
which the head is secured to the shank. The neck may be formed integrally with the
head, but alternatively can be a separate element, which may be made of a different
material. Also, the shank may be directly connected to the head, as is often the case,
for example, with a putter.
[0003] The invention is applicable to all types of golf clubs, such as driver, brassie,
putter, spoon, and all other possible types that may be used in the game of golf.
[0004] British patent application 2,026,927 (Travis) discloses an impact delivery member
for a golf club, made of laminated wood. In the golf club described in the British
application, the shank is formed integrally with the head, the whole being formed
of layers of hard wood veneer, pressed together with intervening synthetic resin.
In the area of the head, supplemental veneers are inserted to achieve the desired
weight and the desired dimensions of the head.
[0005] Golf clubs made in the manner described in British patent application 2,026,927 are,
for example, the golf clubs marketed by Spalding under the name of Top-Flite. In these
known golf clubs, the veneer layers extend transversely to the striking face, that
is to say, transversely to the portion of the head which during striking contacts
the golf ball. As, during striking, large forces act on the head, and in particular
on the striking face, there is the danger that the pressed-together veneer layers,
which in fact are struck with the cross-grain end against the golf ball, come apart.
To obviate this danger, in known golf club heads the striking face is provided with
a plastics face plate.
[0006] Another drawback of the prior impact delivery member is that, with the selected orientation
of the veneers, an integral neck, if any is provided, cannot be of optimum strength
if, as is conventionally the case, the veneer layers are stacked together with the
fibre direction alternately rotated through 90°.
[0007] It is an object of the present invention to overcome the drawbacks and disadvantages
outlined above, and, in general, to provide an effective and durable golf club.
[0008] For this purpose, according to the invention, a golf club of the above-described
kind is characterized in that the layers of the laminated wood extend substantially
parallel to the striking face.
[0009] It is acknowledged that British patent 488,469 discloses an impact delivery member
for a golf club, made of compressed wood having a specific gravity of 1 to 1.40. However,
this prior golf club head is not made of laminated wood.
[0010] Furthermore, British patent application 2,123,701 discloses a golf club head made
partially of compressed laminated wood. The wood layers extend approximately vertically
and transversely to the striking face, so that, here too, there is the drawback that
the head may split. Moreover, this prior head is difficult to make, because it consists
of two parts, which must be secured together very firmly.
[0011] The invention will be described in more detail hereinafter with reference to the
accompanying diagrammatic drawings of some embodiments, given by way of example. In
said drawings,
Fig. 1 is a side-elevational view, showing the striking end of a golf club according
to the invention;
Fig. 2 is a cross-sectional view, taken on the line II-II of Fig. 1;
Figs. 3-5 show a variant of the golf club illustrated in Figs. 1 and 2;
Figs. 6-8 show another variant of a golf club as illustrated as Figs. 1 and 2; and
Figs. 9-11 show still another variant of the golf club of Figs 1 and 2.
[0012] Fig. 1 diagrammatically shows a side-elevational view of the striking end of a golf
club, which includes a striking member 1. The striking member has a head 2 and a neck
3. Neck 3 has an end face 5, which is contiguous with a shank 7 of the golf club.
As shown in dash lines, the shank is sunk into the neck. The head further has a striking
face 4, which serves to hit the ball with. The striking member is made of densified
laminated wood material, such as that commercially available under the name of Lignostone.
[0013] For the manufacture of such a type of densified laminated wood material, wood veneer
layers, such as beech wood veneers are provided on opposite sides with a layer of
synthetic resin material, whereafter the layers are pressed together while being exposed
to elevated pressure and temperature. This operation is continued until the desired
density, i.e., the desired specific gravity, is reached.
[0014] Owing to the compression at high temperature, the synthetic resin material permeates
the wood layers. Preferably, care is taken that the wood is not impregnated with synthetic
resin throughout, but a core layer of non-impregnated wood remains. In the densified
laminated-wood material, the non-impregnated core layers together ensure that the
resiliency of wood as a natural product is sufficiently maintained.
[0015] According to the invention, the head is made from the laminated wood material in
such a manner that the wood layers extend substantially parallel to the striking face.
As the layers are generally flat, and the striking face not, it could also be said
that the layers extend substantially transversely to the striking direction.
[0016] All this is shown in cross-section in Fig. 2. The wood layers are designated by 6
in Fig. 2, and the normal direction of striking is indicated by an arrow P. It will
be seen that the striking surface is somewhat convex, while the wood layers are substantially
flat, so that in this case, strictly speaking, the layers are not parallel to the
striking face. Nevertheless, the wood layers will hereinafter be referred to as being
parallel to the striking face. As used herein, and in the accompanying claims, this
includes a somewhat different situation, as shown in Fig. 2.
[0017] In Fig. 2, the striking member 1 is shown approximately in a position in which the
ball, not shown, is hit by the striking face 4. The arrangement of the wood layers
relatively to the striking face 4, as shown, could be called a vertical arrangement.
Such an arrangement results in an excellent hardness and resilience of the head. This
has been confirmed experimentally. These experiments included shooting 3000 golf balls
from a ball gun against the striking face of a professionally finished and lacquered
striking member according to the present invention, made of beech wood veneer and
densified until a specific gravity of 1.38 was reached. The result was that 30% of
the golf balls had become damaged, whereas the head, and even the lacquer coat were
not damaged at all, i.e. they did not exhibit any dents, cracks, etc. Also, an improvement
in resilience was found: statistically, a golfer drove a golf ball 15% farther with
the striking member according to this invention than with a known striking member
of laminated-wood material in which the layers are directed horizontally at the moment
when the ball is hit.
[0018] Furthermore, the striking member according to the invention is suitable for use under
all weather conditions (tested at temperatures of from -30°C to +80°C).
[0019] Owing to the vertical disposition of the layers of the densified laminated-wood material,
the relevant wood layers 6 can extend from the head into the neck 3 of the striking
member, which considerably improves the strength and hence durability of the striking
member.
[0020] The vertical arrangement of the layers offers the additional advantage that cavities
may be provided in the head without adversely affecting the strength of the head.
[0021] In the past, cavities have been provided in golf club heads for these to be filled
with heavier material. This is in principle unnecessary when densified wood material
is used. Nevertheless, it may be useful to provide one or more cavities in a golf
club head to lower the centre of gravity of the head, which renders it possible to
drive a golf ball through a greater distance. Also, by means of one or more cavities
in the head, the balance of a golf club can be influenced, so that it makes less difference
whether the ball is hit with the heel 8 or the toe 9 of the head.
[0022] Figs. 3-11 show some further embodiments of golf club heads according to the present
invention, provided with cavities. It is noted that, in these figures, the wood layers
are not shown in any detail, but that these extend similarly to those shown in the
head illustrated in Fig. 2.
[0023] Figs. 3-5 diagrammatically show in side elevational view, front-elevational view,
and top plan view, respectively, a golf club head 20 according to this invention,
provided with a cavity 21. In this example, cavity 21 is a blind bore, made from the
top, which is closed with an accurately fitting wooden plug 32. Plug 32 can be made
of normal wood, and, in the example shown, leaves a portion of the cavity clear. The
result of all this is that the centre of gravity of the head has been displaced in
the direction of the sole 23 of the head. This is also the case, but to a lesser extent,
if the plug should fully fill the cavity, so long as the plug is made of lighter material
than the head proper. Thus, for example, the plug could be made of a synthetic plastics
material or, if formed as a relatively thin cover plate, of metal.
[0024] Figs. 6-8 show, in side-elevational view, front-elevational view and top plan view,
respectively, a different example of a golf club head 30 provided with a cavity for
a golf club according to this invention. In this example, a blind bore 32ʹ has been
formed into the head from the sole 31, which bore is closed with a metal plate 33
of a diameter slightly exceeding that of the bore, which plate is countersunk into
the sole. In this way, too, the centre of gravity of the head is lowered. Furthermore,
the balance of the head can be influenced by varying the place of the bore. In this
connection it is noted that the balance can also be influenced by using more than
one bore and/or using a cavity of special shape.
[0025] Figs. 9-11 diagrammatically show in side-elevational view, front-elevational view
and top plan view, respectively, a head 40 for a golf club according to this invention,
provided with an approximately triangular cavity 41, made from the sole 42. The triangular
cavity has a side surface approximately parallel to the striking face 4 and is deeper
at that location, as shown at 43 in the figures. Furthermore, a metal sole plate 44
has been used which, in this example, covers not only the cavity, but the entire sole
of the head.
[0026] It is noted that, in view of the foregoing, various modifications will readily occur
to those skilled in the art. Thus, in principle, a cavity could also be formed in
the head by forming a bore in the side of the head remote from the striking face 4.
So long as such a bore is located above the original centre of gravity of the head,
this will lower the centre of gravity. The balance can, again, be influenced by varying
the place of the bore or other cavity. Furthermore, a cavity of the kind shown in
Figs. 3-5 can be used in combination with a metal plate in the sole 23. These and
similar modifications are deemed to be within the scope of the present invention.
1. A golf club for use in the game of golf, comprising a shank provided at one end
with a striking member made of laminated wood elevated in specific gravity by compression
and having a striking face, characterized in that the layers of the laminated wood
extend substantially parallel to the striking face.
2. A golf club as claimed in claim 1, characterized in that the elevated specific
gravity ranges from about 0.9 to about 1.40.
3. A golf club as claimed in claim 1 or 2, characterized in that the elevated specific
gravity is about 1.38.
4. A golf club as claimed in any of claims 1-3, characterized in that the laminated
wood comprises layers of beech wood veneer.
5. A golf club as claimed in any of the preceding claims, characterized by a metal
plate at the sole.
6. A golf club as claimed in any of the preceding claims, characterized by at least
one closed cavity in the head, spaced from the striking face.
7. A golf club as claimed in claim 6, characterized in that said at least one cavity
is a blind bore formed substantially above the original centre of gravity of the striking
member.
8. A golf club as claimed in claim 7, characterized by a metal plate at the sole.
9. A golf club as claimed in claim 6, characterized in that said at least one cavity
is a cavity formed from the bottom of the striking member, and the axis of which is
substantially parallel to the striking face, the cavity being closed at the bottom
by a metal plate.
10. A golf club as claimed in claim 9, characterized in that the cavity comprises
at least two parts of different depths.
11. A golf club as claimed in claim 9, characterized in that the metal cover forms
a sole plate.
12. A golf club as claimed in any of the preceding claims, characterized by at least
two cavities.
13. A striking member for a golf club as claimed in any of the preceding claims.