Golf club head   

The present invention is a continuation-in-part of U.S. application Ser. No. 11/723,643 filed on Mar. 21, 2007.

1. Field of the Invention

The present invention relates generally to a golf club, and more particularly to a golf club head made of light alloy, such as magnesium alloy or aluminum alloy.

2. Description of the Related Art

A golf club head, which a housing thereof is made of magnesium alloy or aluminum alloy, has many advantages, such as light weight, greater size and lower center of gravity. Especially for a magnesium alloy golf club head, it has a superior vibration absorbing capacity. But, magnesium alloy has a weak strength that is not suitable for the face. To overcome this issue, the face is usually made of the alloy with superior flexibility, such as titanium alloy or stainless. However, magnesium alloy or aluminum alloy has a lower melting temperature than titanium alloy and stainless, so that the titanium alloy or stainless face can't bond to the magnesium alloy or aluminum alloy housing by brazing or other conventional welding. Such golf club head usually has a weal bonding strength between the housing and the face because that the housing and the face are made of different materials.

The primary objective of the present invention is to provide a golf club head, which a housing made of magnesium alloy or aluminum alloy and a face made of titanium alloy or stainless have a strong bonding strength therebetween without the drawback as described above.

According to the objectives of the present invention, a golf club head includes a front member, a rear member and a neck connected together to form a housing. The front member, which is made of a flexible material, such as aluminum alloy, stainless or Maraging steel, has a face and an annular wall projected from a back of the face to form a cup-like member, wherein the wall has a connecting portion at a distal end thereof, and a length of the wall is identical to or greater than 8 mm and a thickness of the wall is identical to or less than 2 mm. The rear member, which is made of a light metal, such as magnesium alloy or aluminum alloy, has a connecting portion to engage the connecting portion of the front member. The neck is fixed on the rear member.

As shown in FIG. 1 to FIG. 4, a golf club head 10 of a first preferred embodiment of the present invention includes a front member 20 and a rear member 30.

The front member 20 is made of a flexible material, such as aluminum alloy, stainless or Maraging steel. The front member 20 has a face 21 and an annular wall 22 projected from a back of the face 21. The front member 20 is a cup-like member. The annular wall 22 has a connecting portion at a distal end. As shown in FIG. 37 a length W of the wall 22 is identical to or greater than 8 mm, and a thickness D thereof identical to or less than 2 mm. In the present embodiment, the length is 10 mm, and the thickness D is 1.5 mm.

The present inventor recommends that the length W of the wall 22 is preferred in a range between 8 mm and 20 mm, and more preferred in a range between 12 mm and 15 mm. The thickness D of the wall is preferred in a range between 0.8 mm and 2 mm.

The rear member 30 is made of a light material, such as magnesium alloy or aluminum alloy. The rear member 30 is a cup-like member also with a greater depth. The rear member 30 has a connecting portion 31 at an open end to be engaged with the connecting portion 23 of the front member 20. As shown in FIG. 3, the connecting portion 23 of the front member 20 has a protrusion and the connecting portion 31 of the rear member 30 has a recess. A thickness S of the rear member 30 between an exterior side and the recess 31 is less than 3 mm. In the present embodiment, the thickness S is 1.5 mm.

The present inventor recommends that the thickness S of the rear member 30 between an exterior side and the recess 31 is preferred in a range between 0.4 mm and 2 mm, and more preferred in a range between 1.0 mm and 1.2 mm.

As shown in FIG. 4, at a bottom of the golf club head 10, the front member 20 has a bottom portion 24 projecting rearwards from a middle thereof, and the rear member 30 has a gap or slot to engage the bottom portion 24. As a result, the bottom portion 24 forms a protective portion at the bottom of the golf club head 10. The bottom portion 24 may be wider to form the whole bottom of the golf club head 10 also. It also may provides the rear member 30 has an indentation at an exterior side (not shown) and the bottom portion 24 of the front member 20 is complementary to the indentation, in other words, the front member 20 and the rear member 30 are overlapped at the bottom portion 24.

The golf club head 10 further includes a neck 11 formed on the rear member 30 to provide vibration absorbing capacity.

Adhesive, such as epoxy resin, is added between the connecting portions 23 and 31 to fix the front and rear members 20 and 30.

The present invention provides the front member 20 made of flexible metal, such as titanium alloy or stainless with the length W of the wall 22 greater than 8 mm, more preferable is 10 mm and the thickness D is less than 2 mm, more preferable is between 1.2 mm and 1.5 mm, such that the wall 22 has a superior flexibility to sustain an impact of swing. The wall 22 has a strain to absorb most of the impact that the connecting portions 23 and 31 sustain less impact. As a result, the thickness S of the rear member 30 may be thinner to reduce the thickness and weight at a crown 13 of the golf club head 10.

As shown in FIG. 5, a golf club head 40 of the second preferred embodiment of the present invention includes a rear member 50 consisting of an upper member and a bottom member 70. The upper member 60 is made of a light metal with a specific weight less than 3 and vibration absorbing capacity, such as industrial plastic, fiber reinforced resin, magnesium alloy or aluminum alloy, and the bottom member 70 is made of a heavy metal with a specific weight greater than 4 and wear-proof capacity, such as stainless, titanium, iron, wolfram made by powder metallurgy or wolfram-copper alloy, which provides the wear-proof and weight distribution effects.

The description above is a few preferred embodiments of the present invention and the equivalence of the present invention is still in the scope of the claim of the present invention.