FR3121048A1 - Putter type golf club head comprising a striking face with a hardness adapted to that of a golf ball - Google Patents

Abstract

Putter-type golf club head comprising a striking face with a hardness adapted to that of a golf ball The subject of the invention is a golf club head (16) made, at least partially over a certain thickness from its striking face (20), in a first material which has a Shore A hardness of less than 35, close to that of a golf ball (18) in order to limit the appearance of vibration phenomena. Figure 1

Description

Putter type golf club head comprising a striking face with a hardness adapted to that of a golf ball

The present application relates to a golf club head of the putter type comprising a striking face with a hardness adapted to that of a golf ball in order to limit the appearance of vibratory phenomena.

A putter is a golf club used to roll a golf ball across a putting green into a hole. It comprises a handle which has at a first end a handle for grasping it and at a second end a head for hitting a golf ball.

This head includes an approximately flat striking face to hit a golf ball as well as a volume with a center of gravity adjusted according to the desired characteristics.

According to one embodiment, the head of the putter is metallic and has a hardness very markedly greater than that of the golf ball. This difference in hardness leads to the appearance of vibratory phenomena, which affects the precision of the blow.

Document US3.211.44 describes a golf club of the putter type which has a metal body as well as a rubber striking face with a Shore A hardness of between 65 and 85. This solution does not allow an optimal reduction of vibrations.

Document US2004/0242342 describes a golf club head which comprises a shell as well as various layers positioned in the shell, including a front layer forming the striking face and at least one intermediate damping layer between the striking layer and the shell. . According to one embodiment, the front layer is metallic or made of a composite material and has a Shore A hardness greater than or equal to 90. As before, this solution does not allow optimal reduction of vibrations.

Document US8,900,071 also describes a golf club head which comprises a shell as well as an insert positioned in the shell. This insert comprises three layers including a front layer forming the striking face, an intermediate layer and a rear layer. According to this document, the front layer has a hardness h1 and an elastic modulus r1, the intermediate layer a hardness h2 and an elastic modulus r2 and the back layer a hardness h3 and an elastic modulus r3, the hardnesses and the elastic moduli being chosen so that h1>h2, h3>h2, r1>r2 and r3>r2.

According to one embodiment, the front layer has a Shore D hardness of between 35 and 65, ie an equivalence in Shore A hardness greater than 80. As before, this solution does not allow optimum reduction of vibrations.

The present invention aims to remedy all or part of the drawbacks of the prior art.

To this end, the subject of the invention is a golf club head comprising a substantially planar striking face configured to strike a golf ball, characterized in that the head is made, at least partially over a certain thickness, from the striking face, in a first material which has a Shore A hardness of less than 35.

The fact that the material of the striking surface and that of the golf ball have similar hardness limits the appearance of vibration phenomena.

1. le premier matériau présente une dureté supérieure à celle d’une balle de golf ;
2. le premier matériau est du bois avec une dureté Janka supérieure ou égale à 1500 lbf (6672 N) ;
3. la tête comprend un corps ainsi qu’une couche avant qui présente une première face formant la face de frappe et une deuxième face opposée à la première face et orientée vers le corps, la couche avant étant réalisée dans le premier matériau ;
4. la couche avant présente une épaisseur comprise entre 3 et 8 mm ;
5. le corps comprend :

• une coque qui présente une surface avant contre laquelle est plaquée la deuxième face de la couche avant ainsi qu’au moins une cavité débouchant au niveau de la surface avant,
• au moins un lest en un deuxième matériau dense, positionné dans au moins une cavité et solidarisé à la coque ;
  1. la couche avant est en contact avec la coque et solidarisée à cette dernière, au moins sur toute sa périphérie ;
  2. au moins un lest est espacé de la couche avant pour obtenir une zone intermédiaire délimitée par le lest, la couche avant et la coque ;
  3. la zone intermédiaire est entièrement comblée d’au moins un troisième matériau choisi pour amortir le bruit ;
  4. les premier, deuxième et troisième matériaux sont choisis de manière à ce que le premier matériau présente une dureté inférieure à celle du troisième matériau qui est elle-même inférieure à celle du deuxième matériau.

According to other characteristics taken individually or in combination:

1. the first material has a hardness greater than that of a golf ball;
2. the first material is wood with a Janka hardness greater than or equal to 1500 lbf (6672 N);
3. the head comprises a body as well as a front layer which has a first face forming the striking face and a second face opposite the first face and oriented towards the body, the front layer being made of the first material;
4. the front layer has a thickness between 3 and 8 mm;
5. the body includes:

• a shell which has a front surface against which the second face of the front layer is pressed as well as at least one cavity opening out at the level of the front surface,
• at least one ballast made of a second dense material, positioned in at least one cavity and secured to the hull;
  1. the front layer is in contact with the shell and secured to the latter, at least over its entire periphery;
  2. at least one ballast is spaced from the front layer to obtain an intermediate zone delimited by the ballast, the front layer and the shell;
  3. the intermediate zone is completely filled with at least one third material chosen to dampen noise;
  4. the first, second and third materials are chosen so that the first material has a lower hardness than that of the third material which is itself lower than that of the second material.

The invention also relates to a golf club of the putter type comprising a head according to one of the preceding characteristics.

Other characteristics and advantages will emerge from the description of the invention which follows, description given by way of example only, with regard to the appended drawings, among which:

is a perspective view of a putter type golf club illustrating one embodiment of the invention,

is a perspective view from a first viewing angle of a golf club head illustrating one embodiment of the invention,

is a perspective view from a second angle of view of the golf club head visible on the ,

is a perspective view illustrating the various parts of the golf club head visible on the ,

is a perspective view of a shell of a golf club head illustrating one embodiment of the invention,

is a top view of the shell visible on the ,

is a schematic representation of a golf club head illustrating one embodiment of the invention,

is a perspective view of a portion of a golf club shaft illustrating one embodiment of the invention, and

is a cross section of the golf club shaft visible on the .

According to an embodiment visible on the , a golf club 10 of the putter type comprises a shaft 12, a handle 14 at a first end 12.1 of the shaft 12 as well as a head 16 connected to a second end 12.2 of the shaft 12 and configured to hit a golf ball 18.

According to one method of manufacture, the golf ball 18 comprises a solid core covered with several layers, the last layer of which is surlyn® or balata for example. The golf ball 18 has a low surface hardness.

The handle 12 can be metallic, composite material or any other material. Apart from its ends, the handle 12 has a cylindrical shape and has an axis of revolution A12. This handle 12 is straight. It may include a curved section called "hossle" at its second end 12.2.

The head 16 comprises a substantially planar striking face 20 as well as a fixing system 22 for the handle 12. According to one configuration, the fixing system 22 comprises a blind hole in which the second end 12.2 of the handle 12 is fitted. other solutions could be considered to connect the handle 12 and the head 16.

The handle 14, the handle 12 as well as the fixing system 22 are not further described because they are known to those skilled in the art.

For the rest of the description, a longitudinal direction DL is substantially perpendicular to the striking face 20. A transverse plane is perpendicular to the longitudinal direction DL.

According to one embodiment visible in Figures 2 and 3, the head 16 comprises a body 24 and a front layer 26 which has a first face 26.1 forming the striking face 20 and a second face 26.2 opposite the first face 26.1 and oriented towards the body 24. Thus, the front layer 26 is pressed against the body 24 at the level of a joint plane 28 (visible on the ). According to one configuration, this front layer 26 has a substantially constant thickness and has a substantially constant cross-section equal to that of the body 24 at the joint plane 28.

According to a feature of the invention, the front layer 26 is made of a first material which has a Shore A hardness of less than 35. Thus, this front layer 26 has a Shore A hardness lower than that of the golf ball 18 increased by 20%. The fact that the front layer 26 and the golf ball 18 have similar hardness limits the appearance of vibration phenomena.

The first material must have a higher hardness than the golf ball 18 to ensure optimal energy transfer between the head 16 and the golf ball 18 when hitting. This hardness greater than that of the golf ball 18 also makes it possible to avoid premature wear of the striking face 20. Thus, the front layer 26 has a Shore A hardness greater than or equal to that of the golf ball 18 increased by 5%.

This front layer 26 has a thickness (distance separating the first and second faces 16.1, 26.2) of between 3 and 8 mm.

As a variant, all or almost all of the head 16 is made of a first material which has a Shore A hardness of less than 35 or less than that of the golf ball 18 increased by 20%. The first material must have a hardness greater than that of the golf ball 18.

Whatever the embodiment, the head 16 is made, at least partially over a certain thickness from the striking face 20, of a first material which has a Shore A hardness of less than 35 or less than that of the ball. golf 18 increased by 20%. The first material has a higher hardness than the golf ball 18.

According to one embodiment, the first material is wood with a Janka hardness greater than or equal to 1500 lbf (6672 N). The hardest woods have a Janka hardness of less than 4000 lbf (17793 N), less in equivalence than a Shore A hardness of 35.

For example, the chosen wood is ebony. Of course, the invention is not limited to this essence. Moreover, the invention is not limited to wood. Thus, other materials with hardnesses within the range given above may be suitable.

According to one embodiment, the body 24 can be monomaterial or comprise a combination of materials, as illustrated in FIGS. 4 and 7. The body 24 can comprise a single element or several assembled elements.

According to one configuration, the body 24 is made of wood and comprises at least one insert providing the ballast function.

According to other configurations visible in Figures 4 and 7, the body 24 comprises a shell 30 which has a front surface 30F against which is pressed the second face 26.2 of the front layer 26 as well as at least one cavity 32 opening at the level of the front surface 30F. This shell 30 can be made of wood, a composite material or any other material.

The body 24 comprises, for each cavity 32, at least one ballast 34 positioned in the cavity 32. This ballast 34 is made of a second dense material, such as lead, tungsten or others.

Each ballast 34 is secured to the hull 30, by gluing or any other similar technique.

According to another characteristic, the front layer 26 is in contact with the shell 30 and secured to the latter, at least over its entire periphery, by gluing or any other similar technique.

Thus, the force and the inertia acquired by the hull 30 and the ballast 34 during the movement of the golf club are transferred by a peripheral surface contact to the front layer 26 during the impact with the golf ball 18 and, this fact, directly transmitted to the latter.

Given the hardness of the front layer 26 or the head 16, the shock of the golf ball 18 is fully absorbed, which limits the appearance of vibration phenomena.

According to one embodiment, at least one ballast 34 is spaced from the front layer 26. Thus, the head 16 comprises an intermediate zone 36 delimited by the ballast 34, the front layer (26) and the shell (30). This intermediate zone 36 can be empty or completely filled with at least a third material chosen to dampen noise. For example, the third material is balsa or plastic foam.

This intermediate zone 36 is positioned in the body 24, in a housing provided on the second face 26.2 of the front layer 26 or on either side of the joint plane 28.

According to another feature, the first material of the front layer 26 has a hardness h26, the second material of the ballast 34 a second hardness h34, the third material of the intermediate zone 36 a third hardness h36; the first, second and third materials being chosen so that the first hardness h26 is lower than the third hardness h36 which is itself lower than the second hardness h34.

The number, dimensions, shapes and arrangement of the cavities as well as the shapes and dimensions of the body are determined according to the characteristics sought for the head 16.

The golf club 10 comprises at least one indicator favoring the positioning and/or the orientation of the hitting face 20 with respect to the golf ball 18 and/or to the desired trajectory of the golf ball 18. For example, the head 16 includes a mark 38 to facilitate alignment of the impact zone with the golf ball.

According to one embodiment visible in Figures 8 and 9, the handle 12 includes a visual cue 40 facilitating the orientation of the striking face 20. This visual cue 40 provides a visual contrast with the rest of the handle 12.

According to one feature, the visual cue 40 is a strip of material with a thickness e projecting from the surface of the handle 12, which extends between a first rectilinear side edge 40.1 and a second rectilinear side edge 40.2, the first and second side edges 40.1, 40.2 being parallel to each other and parallel to the axis of revolution A12 of the handle 12.

The handle 12 has a median plane of PMA alignment which must be correctly oriented so that the hitting face 20 is correctly oriented with respect to the trajectory of the desired golf ball 18. The first and second edges 40.1, 40.2 are positioned with respect to the median alignment plane PMA so that the visual cue 40 is not visible and located in a field of vision 44 of a golfer when the latter prepares his shot and positions the striking face 20 close to the ball 18 or that an area 42 of the handle 12 not covered by the visual marker 40, located at the same height as the latter, is not visible by and located in the field of vision 44 of the golfer when the latter prepares his shot and positions the striking face 20 close to the ball 18. Given the thickness e of the visual cue 40, the first and second side edges 40.1, 40.2 are spaced from the median plane by PMA alignment. Thus, the straight line passing through the first lateral edge 40.1 and the center O of the handle 12 forms with the median alignment plane PMA an angle α identical to that formed between the median alignment plane PMA and the straight line passing through the second edge side 40.2 and the center O of the handle 12. This angle α is between 0 and 5°, preferably between 1 and 3°, for a thickness of the order of a few microns to 2 mm.

According to a first configuration, the distance between each of the first and second side edges 40.1, 40.2 and the median alignment plane PMA is a function of the thickness e of the visual cue 40 and adjusted so that there is only a single angular orientation of the handle 12 around its axis of revolution A12 for which the visual cue 40 is no longer present in the field of vision 44 of the golfer preparing his shot.

Thus, as long as part of the visual cue 40 is located in the golfer's field of vision 44 then the handle 12 is not correctly oriented. As soon as it is no longer visible then the handle 12 and the striking face 20 are correctly oriented.

According to a second configuration, the distance between each of the first and second side edges 40.1, 40.2 and the median alignment plane PMA is adjusted so that there is only one angular orientation of the handle 12 around its axis of revolution A12 for which the zone 42 of the handle 12 not covered by the visual marker 40, located at the same height as the latter, is no longer present in the field of vision 44 of the golfer preparing his shot.

Thus, as long as part of the zone 42 of the handle 12 not covered by the visual cue 40 is located in the field of vision 44 of the golfer, the handle 12 is not correctly oriented. As soon as the zone 42 of the handle 12 not covered by the visual cue 40 is no longer visible then the handle 12 and the striking face 20 are correctly oriented.

Claims (10)

Golf club head comprising a substantially planar striking face (20) configured to strike a golf ball (18), characterized in that the head (16) is made, at least partially over a certain thickness from the striking (20), made of a first material which has a Shore A hardness of less than 35. Golf club head according to claim 1, characterized in that the first material has a hardness greater than that of a golf ball (18). Golf club head according to claim 1 or 2, characterized in that the first material is wood with a Janka hardness greater than or equal to 1500 lbf (6672 N). Golf club head according to one of the preceding claims, characterized in that the head (16) comprises a body (24) as well as a front layer (26) which has a first face (26.1) forming the striking face (20) and a second face (26.2) opposite the first face (26.1) and oriented towards the body (24) and in that the front layer (26) is made of the first material. Golf club head according to the preceding claim, characterized in that the front layer (26) has a thickness of between 3 and 8 mm. Golf club head according to claim 4 or 5, characterized in that the body (24) comprises:

1. a shell (30) which has a front surface (30F) against which the second face (26.2) of the front layer (26) is pressed as well as at least one cavity (32) opening out at the level of the front surface (30F) ,
2. at least one ballast (34) made of a second dense material, positioned in at least one cavity (32) and secured to the hull (30).

Golf club head according to the preceding claim, characterized in that the front layer (26) is in contact with the shell (30) and secured to the latter, at least over its entire periphery, at least one weight being spaced from the front layer (26) to obtain an intermediate zone (36) delimited by the ballast (34), the front layer (26) and the hull (30). Golf club head according to the preceding claim, characterized in that the intermediate zone (36) is entirely filled with at least a third material chosen to dampen noise. Golf club head according to the preceding claim, characterized in that the first, second and third materials are chosen so that the first material has a hardness (h26) lower than the hardness (h36) of the third material which is itself -even lower than the hardness (h34) of the second material. Golf club comprising a head according to one of the preceding claims.