Iron golf club head including weight members for adjusting center of gravity thereof

An iron golf club comprising:

• a club head;
• and
• a shaft connected to said club head,
• said club head comprising a head body made of light metal, said head body having a front surface, a rear surface, a cavity disposed at said rear surface, and at least four holes disposed in the rear surface between a lower side wall of said cavity and a sole of said head body,
• said at least four holes forming groups of holes, each of said groups including two or more holes located at a toe part and at a heel part of said head body, respectively, said holes in each of said groups being spaced at predetermined intervals;
• a plurality of weight members fitted into said at least four holes to a predetermined depth, respectively,
• each of said weight members being oriented in a direction toward the front surface of said head body, and each of said weight members being formed of a material having a specific weight that is heavier than a specific weight of the light metal forming said head body, thereby adjusting the location of the center of gravity between the toe part and the heel part of said head body,
• wherein the weight percentage of said weight members is not more than forty percent of the total weight of the club head, and
• wherein each of said weight members has a diameter that is larger than a diameter of the respective hole in said head body and is press-inserted into the respective hole to a predetermined length so far as the length is within the depth provided by the respective hole.

An iron club set including long iron golf clubs and short iron golf clubs, each of said iron golf clubs including a club head, comprising:

• a head body made of light metal and having a front surface, a rear surface, a cavity disposed at said rear surface, and at least four holes disposed in the rear surface between a lower side wall of the cavity and a sole of said head body,
• said at least four holes defining groups of holes, each of said groups including two or more of said holes,
• said groups being located at a toe part and at a heel part of said head body, respectively, wherein said holes in each of said groups are spaced from each other at predetermined intervals;
• a plurality of weight members fitted into said holes, respectively, and each of said weight members being oriented in a direction toward the front surface of said head body and extending in said respective hole to a predetermined depth, each of said weight members being formed of a material having a specific weight that is heavier than a specific weight of said light metal, thereby adjusting the location of the center of gravity between the toe part and the heel part of said head body,
• wherein the weight percentage of said weight members is not more than forty percent of the total weight of the club head, and
• each of said weight members has a diameter that is larger than a diameter of said respective hole in said head body and is press-inserted into said respective hole to a predetermined length so far as the length is within the depth of said respective hole,
• wherein said weight members are arranged in the club head of each of said long iron golf clubs so that the center of gravity established by said weight members is positioned at the toe part across the bottom center portion of said head body, and
• said weight members are arranged in the club head of each of said short iron golf clubs so that the center of gravity established by said weight members is positioned at the heel part across the bottom center portion of said head body.