FIELD OF THE INVENTION

The present invention relates generally to a golf club head having a multi-layered striking face. More specifically, the striking face of the golf club head in accordance with the present invention is further comprised of an external frontal face layer, an internal rear face layer, and an intermediary sandwiched face layer juxtaposed between the external frontal face layer and the internal rear face layer.

BACKGROUND OF THE INVENTION

Modern day golf club design has evolved since the early days of golf. The good news of all the technological advancements in golf club technology is that it makes the game of golf easier for golfers of all skill levels. However, all these advancements come with tremendous challenges for the golf club engineer.

One of the latest trends in golf club design is the utilization of multiple different materials in the same golf club head to take advantage of the individual performance characteristics the base material, and combining them to create a better performing golf club head. U.S. Pat. No. 6,406,382 to Deshmukh et al. shows an example of utilizing multiple different materials in a golf club head. More specifically, U.S. Pat. No. 6,406,382 to Deshmukh et al. contemplates using high density components such as tungsten, copper, and/or chromium in a golf club head to help improve the weighting of a golf club head.

U.S. Pat. No. 9,844,230 to Snyder shows an iron body and a ball striking plate engaged with the iron body. The ball striking plate may include a face layer and a backing layer of a polymeric material to isolate the face layer from the iron body.

It should be noted that although the utilization of multi-material golf club head has been around, the industry has always been perplexed by the utilization of multi-material around the striking face portion of the golf clubhead due to the high amount of stress when impacting a golf ball. The present invention focuses on a golf club head having a multi-layered, multi-material striking face of a golf club head to further improve the performance of a golf club head.

BRIEF SUMMARY OF THE INVENTION

One aspect of the present invention is a golf club head comprising of a striking face portion located at a frontal portion of the golf club head. More particularly, the present invention contemplates a hollow iron construction with a multi-layer striking face. The striking face portion comprises an external frontal face layer located at an external frontal portion of the striking face portion, an internal rear face layer located at an internal rear portion of the striking face portion, and an intermediary sandwiched face layer, juxtaposed between the external frontal face layer and the internal rear face layer; wherein the internal rear face layer comprises a polymeric material having a flexural modulus within the range of about 30 ksi and 75 ksi, and more preferably, 50 ksi and 75 ksi. Moreover, the polymeric material preferably has a tensile strength to yield within the range of about 1.5 ksi and 8.5 ksi, and more preferably, 2 ksi and 8 ksi. Preferably, the intermediary sandwiched face layer and the external frontal face layer are completely unconstrained around their perimeters. Moreover, the external frontal face layer has an outer surface with an external frontal face layer area that is less than an area of the intermediary sandwiched face layer outer surface, which is less than an area of the internal rear face layer.

In another aspect of the present invention is a golf club head comprising of a striking face portion located at a frontal portion of the golf club head and an aft rear portion attached to the rear of the striking face portion forming a hollow iron type construction. The striking face portion further comprises of an external frontal face layer located at an external frontal portion of the striking face portion, an internal rear face layer located at an internal rear portion of the striking face portion, and an intermediary sandwiched face layer, juxtaposed between the external frontal face layer and the internal rear face layer; wherein the intermediary sandwiched face layer comprises a polymeric material having a Shore D button hardness of between about 55 to 75, wherein the intermediary sandwiched face layer has a uniform thickness, and wherein the internal rear face layer has thicker section juxtaposed the sole and extending approximately 5% to 20% up the face from the sole toward the topline. The external frontal face layer can have a uniform thickness or have a variable thickness wherein the thickness juxtaposed the sole is less than the remainder of the external frontal face layer. In either embodiment, the frontal, outer surface of the external frontal face layer is substantially planar.

Another aspect of the present invention is a golf club head comprising a striking face portion located at a frontal portion of the golf club head and an aft rear portion attached to the rear of the striking face portion forming a hollow iron type construction. The striking face portion further comprises of an external frontal face layer located at an external frontal portion of the striking face portion, an internal rear face layer located at an internal rear portion of the striking face portion, and an intermediary sandwiched face layer, juxtaposed between the external frontal face layer and the internal rear face layer. Preferably, the internal rear face layer is a face insert that is welded to the aft rear portion adjacent the topline and along the sole, between 20% and 70% of the distance from the leading edge to the back edge. The internal rear face layer has thicker section juxtaposed the sole and extending approximately 5% to 20% up the face toward the topline and approximately 5% to 60% along the sole from the leading edge toward the back edge. The external frontal face layer can have a uniform thickness or have a variable thickness wherein the thickness juxtaposed the sole is less than the remainder of the external frontal face layer. In either embodiment, the frontal, outer surface of the external frontal face layer is substantially planar.

In another aspect of the present invention, a golf club head comprises a striking face portion located at a frontal portion of a hollow iron type golf club head that comprises of an external frontal face layer located at an external frontal portion of the striking face portion, an internal rear face layer located at an internal rear portion of the striking face portion, and an intermediary sandwiched face layer, juxtaposed between the external frontal face layer and the internal rear face layer; wherein the internal rear face layer further comprises a face center region that has a thickness of between about 0.5 mm to about 1.2 mm. The external frontal face layer has a face center region that has a thickness greater than the thickness of the internal rear face center region and is between about 0.8 mm to about 1.4 mm. Still further, the intermediary sandwiched face layer is made out of a polymeric material having a Shore D button hardness of between about 55 to 75 and has a face center region with a thickness of between 0.8 mm and 1.4 mm.

In another aspect of the present invention, a golf club head comprises a striking face portion located at a frontal portion of a hollow iron type golf club head that comprises of an external frontal face layer located at an external frontal portion of the striking face portion, an internal rear face layer located at an internal rear portion of the striking face portion, and an intermediary sandwiched face layer, juxtaposed between the external frontal face layer and the internal rear face layer; wherein the internal rear face layer further comprises a face center region that has a thickness of between about 0.5 mm to about 1.2 mm and a leading edge region having a thickness of between about 1.0 mm and 1.5 mm. The external frontal face layer has a face center region that has a thickness greater than the thickness of the internal rear face center region and is between about 0.8 mm to about 1.4 mm and a leading edge region thickness of between about 0.6 mm and 1.0 mm. Preferably, the leading edge of the internal rear face layer has a thickness is approximately 20% to 50% thicker than the internal rear face layer thickness at the face center. Still further, the intermediary sandwiched face layer is formed from a thermoplastic polymeric material having a Shore D button hardness of between about 55 to 75 and has a face center region with a uniform thickness of between 0.8 mm and 1.4 mm.

In another aspect of the present invention, a golf club head comprises a striking face portion located at a frontal portion of a hollow iron type golf club head that comprises an external frontal face layer located at an external frontal portion of the striking face portion, an internal rear face layer located at an internal rear portion of the striking face portion, and an intermediary sandwiched face layer, juxtaposed between the external frontal face layer and the internal rear face layer; wherein the internal rear face layer has an outer surface that is planar and has a first frontal surface area. The intermediary sandwiched face layer is formed from a thermoplastic polymeric material having a Shore D button hardness of between about 55 to 75 and has an outer surface with a second frontal surface area that is between 90% and 99% of the first frontal surface area. Moreover, the external frontal face layer is completely separated from the internal rear face layer by the intermediary sandwiched face layer and has a planar outer surface having a third frontal surface area that is between 90% and 99% of the second frontal surface area.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.

