FR2768936A1 - Iron clubs for golf - Google Patents

Abstract

The series of clubs each have an angled handle with a grip and a head (4). The distance (D) between the neck (13) and the end point (E) of the heel increases progressively from the short to the long clubs. The distance between the point and the end of the heel increases progressively from the short to the long clubs. A projection (20) of increasing volume is formed on each club from the short to the long clubs in the set.

Description

SERIES OF FERS FOR THE PRACTICE OF GOLF
Technical area
The invention relates to golf clubs known as irons; it is more particularly a correlated series of irons for the practice of golf.

Previous techniques
As is known, a golf club (see Figure 1), designated by the general reference (1), essentially comprises two parts, namely a handle (2) with at its upper free end a handle (3) aligned with a rectilinear longitudinal axis (I-I ') connected at its other end to a head (4).

 More generally, on the irons, the head comprises an inclined striking face (5) having a striated surface (6) forming a strike zone of the ball, delimited on each side respectively by a wide zone forming a tip (9), and a narrow zone forming a heel (10), and a rear face (7) spaced from the front face (6). This striking face is limited at the bottom by a lower edge (11) defining a sole (12) disposed between the tip (9) and the heel (10), on the top by an upper edge (13) and the tip (9) and the heel (10).

 The head (4) also comprises a neck designated by the general reference (15), having a connecting zone (8) forming an integral part and disposed in the vicinity of the heel (10), extended by a socket (16) intended to receive the lower end of the handle (2) by engagement in the hollow portion (17) of the socket (16).

 As is known, the opening angle a (see FIG. 3) of the plane containing the striking face (5) with respect to the vertical plane P integrating the axis of the handle when the head is in the address position, decreases from short irons (wedge W or lob L) to long irons (numbers 1,2 or 3).

 Similarly, in the same series of clubs, the so-called lie angle (angle ss in FIG. 5) measured in the plane P between the longitudinal axis of the sleeve II 'and the ground, when the club is also at the address, decreasing from short irons to long irons.

 When impacting the club head on the ball, it is important that the club head remains as close as possible to the ideal position or position to reduce the risk of ball deviations. Indeed, the impact, several deformations occur, the main is a torsion of the head (4) relative to the longitudinal axis (I-I ') of the handle (2). This results in a loss of precision prejudicial to the game.

 By projecting the club head (4) along a plane parallel to the plane P of FIG. 4, when the position of the neck (15) or more precisely that of the longitudinal axis II 'with respect to the striated striking surface (6) is offset from the end (21) of the heel (10) such that the extension of the outer generatrix of the neck (15) intersects the extreme zone of the heel; this offset is then designated by the American term Inset (Fig. 2).

On the other hand, projecting the club head (4) according to a plane parallel to the plane
Q of Figure 4, when the position of the neck (15) or more precisely that of the longitudinal axis II 'is offset from the most advanced point of the lower edge (11) (see Figure 3); this offset is then designated by the American term Offset.

 In US-A-4 986 541, there is described a correlated series of irons in which the distance between the longitudinal axis of the handle and the most advanced point of the lower edge of the club head (offset), responds to a variation law for each iron of the series (see Figure 3c of this document).

 In US-A-5,312,105, the Applicant has described an iron head, successfully commercialized under the reference 792, according to which the longitudinal axis (I-I ') of the handle (2) meets the face of strike (6) inside the striker strike zone.

 US-A-5,607,363 discloses a series of irons in which the longitudinal axis of the handle is offset from the end of the heel (inset) by curvature of the neck above its point of connection with the heel, and varies from one club to another, and in which the distance between the center of gravity of the head and the extension of the longitudinal axis of the handle varies from one club to another in the opposite way to that of this shift.

Brief description of the invention
The invention relates to a series of golf irons in which the distortions of the head relative to the handle during impact are strongly attenuated, which allows good accuracy of play.

This series of irons for the practice of golf, in which each iron includes:
a handle aligned on a rectilinear longitudinal axis, presenting two
ends of which the free upper end receives a
handle and the lower end receives a striking head;
a striking head proper including a striking face
slanted, having a striated front zone for striking the ball
delimited on each side respectively by a wide zone forming a
tip and a narrow area forming a heel, and, on the bottom by a ridge
lower and on the top by an upper edge;
a neck forming an integral part of the head having a zone of
connection, arranged in the vicinity of the heel, extended by a
socket for receiving the lower end of the handle, and wherein the opening angle of the plane containing the striking face with respect to the vertical plane integrating the axis of the handle when the head is in the address position, decreases since the so-called short irons up to so-called long irons.

This series of irons is characterized by:
in that the distance D between the longitudinal axis of the neck and the point
extremal of the heel gradually grows from short irons to long irons,
in that the distance between the end of the tip and the end of the heel
grows gradually from short irons to long irons,
in that the portion of the heel that extends between the extreme point of the heel and
the plane parallel to the longitudinal axis of the neck, tangent to the extreme point
higher than the neck and perpendicular to the striking face, forms a
protuberance of increasing volume from short irons to irons
long,
and in that the center of gravity of said protrusion is located in
below the center of gravity of the complete head, when the iron is in
address position.

 In the description and in the claims, extreme end point of the heel, denotes the furthest point of the end of the iron called tip.

The first characteristic of the invention, according to which the distance D between the longitudinal axis of the neck and the extreme end of the heel increases progressively from short irons to long irons, is justified by the fact that the center of gravity
CG is projected in Gl on the plane P (see Figure 4), while D increases from short irons to long irons, the distance L between G1 and the axis II 'decreases (see Figure 5).

This has the effect of reducing the twisting moment on the long irons used for the very powerful strikes, which we know do not tolerate a large dispersion angle.

 The second characteristic, in which the distance between the end of the tip and the end of the heel increases from short irons to long irons, allows to add the mass on the protrusion characteristic of the invention.

 The third characteristic of the invention, according to which the portion of the heel forming a volume protuberance which also grows from short irons to long irons, contributes to reducing the distance L by bringing the projection G1 closer to the center of gravity of the axis. II 'and thereby, diminutan the arm of the torsion torque for the long irons.

 The fourth characteristic of the invention, according to which the center of gravity of the protuberance is situated below the center of gravity of the whole head when the iron is in the address position, has the advantage of lowering this center of gravity. which allows the ball to take off in an ideal trajectory; it is therefore important that the characteristic protuberance of the invention has a center of gravity as low as possible.

 In summary, the combination of the first three features reduces the significant torque effect on long irons, while the fourth feature maintains a good position of the center of gravity relative to the ground.

 In practice, the distance D increases linearly and regularly.

It increases for example from 5 to 16 mm from the wedge to the iron 3 and is in practice between 8 and 16 mm
In a practical embodiment, the distance D can vary gradually on each of the irons. It can also vary on at least three successive irons. It may also vary, for example, in steps of three irons of SW with iron 8, iron with iron with iron 4 and iron with iron with iron, or with five steps, for example with SW with iron 9, irons 8 and 7, irons 6 and 5, irons 4 and 3, irons 2 and 1.

 According to an essential characteristic of the invention, the heel has a protrusion of increasing importance on each of the irons of the series when the opening angle also said loft loft decreases, that is to say by going from the the shortest iron to the longest iron. This protuberance has a shape corresponding generally to the extension of the lower edge limiting the sole and the upper edge, ignoring the neck connection area. This protuberance results from the approximation of the axis of the handle or its connection zone to the head, towards the center of percussion of the ball on the striking zone. This allows a reduction of the torque on the clubs intended to obtain great distances of balls, thus to reduce the imprecision due to the torsions of the head during the impact.

 In an advantageous embodiment, this protuberance is disposed on the opposite side to the tip relative to the longitudinal axis of the handle, and is connected by a curvilinear shape from the edge of the sole, more precisely from the lower edge, to the bottom of the socket at the height of the upper edge, so as to maintain the center of gravity of the head as close as possible to said sole.

 In other words, this protuberance is disposed between the sole and the bottom of the socket and not above it, and this as already said, so as to lower as much as possible the center of gravity with respect to the sole, which is very favorable to the accuracy of the shot.

 It goes without saying that the distance between the longitudinal axis of the handle and the end of the protrusion of the heel must be at most 16 mm to meet the requirements of Appendix II 4. lob USPGA rules.

 In one embodiment of the invention, the axis of the neck is as already said, offset from the extreme point of the heel and the importance of this offset increases gradually with the inclination of the striking face, while simultaneously, the distance between the axis of the neck and the center of gravity (CG) of the clubhead is kept constant for each clubhead of the series.

 If more generally, the neck is cylindrical, it can also be slightly frustoconical. The characteristic distance D is, in the same way, measured between the longitudinal axis of the handle II 'and the extreme tangent plane of the heel.

Brief description of the figures
The manner in which the invention can be realized and the advantages which derive therefrom will emerge more clearly from the following exemplary embodiments, in support of the appended figures, in which
- Figure 1 is a schematic summary of a golf club
says iron;
FIGS. 2 and 3 are a schematic representation of the head of this iron
shown respectively in front view (Figure 2) and in side view (Figure 3);
- Figure 4 is a top view of the head of an iron;
FIGS. 5, 6 and 7 show a series of three different correlated bars.
according to the invention;
FIG. 8 is a schematic representation in summary perspective
an iron head according to the invention;
FIG. 9 is an illustration of the progressive offset of the protuberance
characteristic of the heel according to the invention for three irons of a
represented respectively in solid lines, in dashed lines and in
dashed;
FIG. 10 schematically illustrates a series of correlated irons according to
the invention.

Ways to realize the invention
An iron head according to the invention shown in a summary perspective in FIG. 8 comprises, in addition to the features mentioned above and listed by the same references, a protuberance (20) disposed on one side of the longitudinal axis ( I-I ') of the handle (2) corresponding to the heel (10), limited by an arc (21) from the edge (22) of the sole (11) to the bottom (23) of the interlocking (16) in alignment with the upper edge (13). Thus, the center of gravity (CG) of the head (4) remains as close as possible to the sole (12).

 According to a first characteristic of the invention, the distance D between the longitudinal axis (I-I ') of the neck and the end (E) of the heel (10) increases gradually from the wedge (FIG. 7) where it is minimum, up to iron 1, as shown in Figure 4.

 Figure 6 is a representation of an intermediate iron no. 5 of this series of irons.

 FIG. 9 represents the three irons of FIGS. 5, 6 and 7 in superposition, which makes it possible to visualize the variations of iron width C, the variations of the angle of ss and the variations of distance D.

 The law of linearly progressive variation is shown in Figure 10. The upper curve A represents the gradual variation of this distance D for a series of irons intended for average players, while the lower curve (B) shows this variation for a good player , especially a professional player.

 In a practical embodiment, as already said, this distance D varies between 5 and 16 mm.

In one form of execution:
for the short irons W, and 9 and 8, the distance D is between 5 and
10 mm.
for medium irons 7 to 4, the distance D is between 10 and 13 mm
while for long irons 3 to 1, the distance D is between 13 and
16 mm.

In a third embodiment, the distance D is for irons:
w to 9 6 <D <7 mm
8 and 7 <D <9 mm
6 and 5 9 <D <11 mm
4 and 3 11 <D <14 mm 3 to 14 <D <16 mm
According to another characteristic of the invention, the distance between the center of gravity of the club head and the virtual axis of the neck, is substantially constant for each club head of the series, to the machining tolerances.

 The distance of the center of gravity relative to the axis of the neck in the longitudinal axis I-I 'of the handle, has no direct effect on the moment of the neck exerted during the impact of the striking surface on the ball. On the other hand, the distance L, that is to say the distance between the projection point G1 of the center of gravity on the plane P with respect to the axis of the handle, is very important because it is the lever arm defining the torsion moment.

 It is known that when the player uses long irons, he intentionally accelerates the speed of the clubhead before impacting the ball. It is the relatively long length of the shaft combined with the mass of the clubhead which helps to increase the speed of the head on impact. However, any deviation of the impact surface of the club during the impact relative to the square position perpendicular to the desired goal line, amplifies the dispersions of the ball, especially over long distances. In this way, the characteristic of the approximation of the neck of the impact zone makes more precise the heads of long irons.

 With short irons with a shorter shaft, the player prints a lower speed to the head on impact. It follows that with the clubs of the invention, the protuberance is less necessary with short irons.

 As already said, FIG. 9 superimposes three clubs, respectively a club W (30) represented in continuous lines comprising a standard bead (33), an intermediate club such as an iron 5 (31) represented in broken lines, presenting a slight protrusion (34) and a long club such as an iron 1 (32) shown in dotted lines with a protrusion (35) appreciable. It can be noted that the length of the blade C or the distance between the heel and the tip increases with the long irons while the angle of lie ss decreases.

 Figure 10 schematically illustrates a series of interrelated irons according to the present invention, showing the gradual increase of the inset, that is to say neck shifts relative to the heel for clubs ranging from short irons said long iron wedge says 1.

 Golf irons according to the invention have an attenuated distortion of the head relative to the handle during the impact, which allows good accuracy of play, both for the average players for professional players.

Claims (10)

 1 / series of irons for the practice of golf, wherein each iron comprises:  a handle (2) aligned on a rectilinear longitudinal axis (I-I '), presenting  two ends among which the free upper end receives a  handle and the lower end receives a striking head (4);  a striking head (4) itself comprising a striking face (6)  slanted, having a striated front zone for striking the ball  delimited on each side respectively by a wide zone forming a  tip (9) and a narrow zone forming a heel (10), and on the bottom by a  lower edge (11) and on the top by an upper edge (12);  a neck (15) forming an integral part of the head comprising a zone of  connection, arranged in the vicinity of the heel (10), extended by a  socket (16) for receiving the lower end of the handle (2), and wherein the opening angle of the plane containing the striking face (6) '(with respect to the vertical plane integrating the axis of the handle ( 2) when the head is in the address position, decreases from so-called short irons to so-called long irons.  in that the distance D between the longitudinal axis I-1'du neck (13) and the point  extremal E of the heel (3) gradually increases from short irons to irons  long,  in that the distance between the tip end (9) and the end of the  heel (10) increases gradually from short irons to irons  long,  in that the portion of the heel that extends between the extreme point E of the heel  (10) and the plane parallel to the longitudinal axis I-I 'of the neck (15), tangent to the  highest point of the neck and perpendicular to the striking face,  forms a protuberance (20) of increasing volume from the short irons  to long irons,  . and in that the center of gravity of said protrusion is located in  below the center of gravity CG of the complete head, when the iron is in  address position.  2 / series of irons according to claim 1, characterized in that the distance D increases linearly and regularly.  3 / series of irons according to claim 2, characterized in that the distance D increases from 5 mm for the wedge up to 16 mm for the iron (3).  4 / Series of irons according to claim 1, characterized in that the distance D varies gradually on each of the irons.  5 / series of irons according to claim 1, characterized in that the distance D varies stepwise on three successive irons.  6 / Series of irons according to one of claims 1 to 5, characterized in that the protuberance (20) has a shape corresponding generally to the extension of the lower edge (11) limiting the sole and the upper edge (13). ) excluding the connecting zone (8) of the neck (15)  7 / series of irons according to claim 6, characterized in that the protuberance (20) is disposed on the opposite side to the tip (9) relative to the longitudinal axis II 'of the handle (2), and is connected by a curvilinear shape (21) extending from the edge (22) of the sole (11) to the bottom (23) of the socket (16) in alignment with the upper edge (13) to maintain the center gravity of the head as close as possible to the sole.  8 / series of irons according to one of the preceding claims, characterized in that the axis II 'of the neck (15) is offset from the extreme point E of the heel (10) and the importance of this shift increases gradually with the inclination of the striking face, while simultaneously, the distance between the axis of the neck (15) and the center of gravity (CG) of the club head is kept constant for each club head of the series.  9 / Series of irons according to one of the preceding claims, characterized in that:  for the short irons W, and 9 and 8, the distance D is between 5 and 10  mm.  for medium irons 7 to 4, this distance D is between 10 and 13  mm  and in that for the long irons 3 to 1, the distance D is between 13  and 16 mm.  10 / series of irons according to one of claims 1 to 8, characterized in that the distance D in mm is comprised:  for irons W to 9 6 <D <7 mm  for irons 8 and 7 7 <D <9 mm  for irons 6 and 5 9 <D <l1 mm  for irons 4 and 3 11 <D <14 mm  for irons 3 to 1 14 <D <16 mm