Golf Club Head with Ripple Structure

Abstract

A golf club head with a shell structure constituting with a body part and a hitting surface (face) incorporates, a groove is formed in the body part near the interface with the hitting surface. Several additional ripples are formed in the inner surface of the face plate. The groove in the body part and ripples of the inner surface of the face plate contributed as a powerful shock absorber but also preventing breakage of the head as well as strong repulsive mechanism improving flying distances.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of Invention

[0002] This invention relates generally to golf clubs and more particularly to the improvement of the driver head and fairway metal head.

[0003] 2. Description of Prior Art

[0004] Conventional golf clubs especially drivers have been improved to maximize flying distances by increasing repulsive power of driver's striking face. Early efforts have lead to thin head faces with supporting structures (U.S. Pat. No. 5,776,001) to prevent breakage. Lately, more advanced structures such as volcano or convex like shapes (U.S. Pat. No. 5,830,084, U.S. Pat. No. 5,954,596 or U.S. Pat. No. 7,338,338 B2) with thick center portions and thin peripheral portions have been developed to increase repulsive power without breakage from high ball contact stress.

[0005] Even though the recent improvements described prevent breakage of the sweet spot area, these kinds of structures suffer from having the weight in the center face which result in a smaller MOI, and having a fragile peripheral region near the boundary of the face. Consequently, sometimes breakage of the driver face occurs as the driver strikes a ball outside of the sweet spot.

SUMMARY OF INVENTION

[0006] This invention was thought out to solve the problems mentioned above. Based on the impact mechanics, as the driver head face impacts the golf ball, the impact area absorbs shock energy and stores it by flexing backward at the moment of impact. The flexed driver head face improves energy transfer efficiency to the golf ball. Additionally, the flex of the driver head face results in a lower peak stress. By achieving this driver head face flex without substantial thinning of the sweet spot periphery, the proposed invention avoids the breakage issues associated with previous designs.

[0007] At ball impact, significant bending stresses are imparted to the club head face due to the kinetic energy transfer (E=mv.sup.2/2 where m is the mass of the head and v is the speed of the head). If the stress of impact exceeds the material limits, the club head face or adjacent area can crack.

[0008] In most cases, microscopic observation shows that this cracking phenomenon of the of the face plate is triggered by the separation of the inner metal surface. The cracking phenomenon is due the impact stresses exceeding the allowable stresses of the inner surface of the faceplate. Breakage of the body (shell) can also occur as the ball hits the adjacent area to the body. In this case, impact energy cannot be absorbed and most impact energy is concentrated upon the body part near the hitting area.

[0009] This invention provides a golf club having improved ball flight distances with relatively lower breakage rate of the club head. This is achieved by adding a groove as a shock absorbing device on the body part adjacent to the hitting area and constructing several donut or spiral shaped ripples on the inner surface of the face plate of hitting surface.

[0010] To achieve the goal mentioned above, the head of the golf club must have shell type construction which is composed of a hitting area and a body area which includes a groove and a hosel that is connected to a shaft.

[0011] Conventionally, the face of the club head absorbs impact energy at the moment of impact against the golf ball and the face is bent in the opposite direction of the club head's movement. However, with the proposed structure, which has a slightly larger inner surface of a face plate than conventional structures, the stress diverges very fast through the thin and thick parts formed alternately as concentric rings (or ellipses). Consequently, regardless of the impact spot of the face, the stress per unit area is lower than that of conventional drivers and thus lowers the brakeage rate of the driver head.

[0012] Due to improved repellant power by the thin parts of the ripples (valley) and the raised maximum impact strength of the thick part of the ripples (peak), the club head has increased the driving distances with a lower breakage rate compared to the conventional designs. Also, the groove adjacent to the face works as a shock absorber and absorb the impact energy when the impact occurs on the peripheral region of the face.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 shows a perspective view of this invention

[0014] FIG. 2 shows a cross sectional view of the club head that shows ripples in the body part

[0015] FIG. 3 shows a rear view of hitting surface on first embodiment of this invention

[0016] FIG. 4 shows a cross sectional view of hitting surface on first embodiment of this invention

[0017] FIG. 5 shows a rear view of hitting surface on second embodiment (spiral) of this invention

[0018] FIG. 6 shows a cross sectional view of hitting surface on second embodiment (spiral) of this invention

DESCRIPTION OF THE FIRST EMBODIMENT OF INVENTION

[0019] The first embodiment of this invention illustrated as in FIG. 1 is constructed with a thin shell type body part 1 and hitting surface part 10. A groove 5 is formed on the body part 1 near the hosel 3 and adjacent to the hitting surface 10.

[0020] The groove 5 on the body part 1 starts right next from the hosel 3, stretched along the top 7 of the body part 1 and continues all the way to the opposite side of the hosel 3. The cross section of the groove 5 has a half cylinder shape.

[0021] The first embodiment of the inner surface of the face plate of hitting area is formed with oval shaped lines of peaks 22, 24, 26 and valleys 21, 23, 25, 27 which are as illustrated in FIGS. 3 & 4. Reference to the front surface 19 of hitting area 10, the height of the peaks 22, 24, 26 and the valleys 21, 23, 25, 27 are highest in the center and get lower as it move away from the center.

[0022] With a detailed description, the thickness D21 of the valley 21 is thicker than the thickness D23 of the valley 23, the thickness D23 of the valley 23 is thicker than the thickness D25 of the valley 25 and the thickness D25 of the valley 25 is thicker than the thickness D27 of the valley 27. Also, the height D22 of the peak 22 is higher than the height D24 of 24 and the height D24 of the peak 24 is higher than the height D26 of the peak 26.

[0023] These peaks 22, 24, 26 and valleys 21, 23, 25, 27 are connected smoothly such as sign or cosine type waves with no sharp edges.

DESCRIPTION OF THE SECOND EMBODIMENT OF INVENTION

[0024] As illustrated in FIGS. 5 & 6, the second embodiment of this invention has a spiral shaped series of peaks. First peak 30 starts at the center of the inner surface of the face plate 20 of hitting area 10 and last peak 31 ends at the peripheral of the inner surface of the face plate of hitting area. Furthermore, the height D30 of the peak 30 is the highest and starts to get gradually lower and connected to the peak 31 which is the lowest part D31 of the line of peaks.

[0025] Similarly the valley 40 at the center of the inner surface 20 is lined smoothly with the valley 41 on the peripheral of the inner face and the thickness D40 of the valley 40 at the center of the inner face 20 is the thickest and the thickness D41 of the valley 41 on the peripheral of the face is the thinnest among The thickness of the valley 40 becomes shallower gradually meeting the valley 41 smoothly where the peak 31 ends.

Claims

1. A golf club head with groove in the body part comprising ellipse shaped ripples with at least more than two valleys and two peaks on the inner surface of the face plate.

2. A golf club head with groove in the body part comprising at least more than one spiral shaped peak and valley on the inner surface of the face plate.

3. A golf club head as claimed in claim 1 & 2, wherein: center of the inner surface of the face plate forms as a valley of the ripple and boundary of the inner surface of the face plate also forms as a valley of the ripple.

4. A golf club head as claimed in claim 1 & 2, wherein: height of the peaks are higher as those closer to the center and are lower as those closer to the boundary of the inner surface of the face plate referenced on the front face of hitting surface.

5. A golf club head as claimed in claim 1 & 2, wherein: peaks and valleys in the ripple structures are connected smoothly with no sharp edges