Apparatus for cutting a stone member so as to have a curved surface

An apparatus for cutting a stone member so as to have a curved surface, which comprises:

• an endless wire saw disposed horizontally and driven by an electric motor and having a plurality of cutting parts including a diamond powder cutting part and being moveable vertically by an electric motor, and a carriage supporting and feeding a stone member and moveable in the cross direction underneath said wire saw by an electric motor;
• an optical following device having a table movable in a horizontal and straight direction by said electric motor for driving said carriage with a velocity having a predetermined ratio with respect to the velocity of said carriage for supporting a model member made of a sheet of material,
• a movable member guided in a perpendicular direction against to the direction of movement of said table by a guide member disposed at a fixed position along the surface of said table and movable by the downward movement of said wire saw by a velocity transmitting device with the velocity having a predetermined ratio with respect to the downward velocity of said wire saw, and
• an optical sensor attached to said movable member, wherein said optical sensor is movable a prescribed length from a position at a starting position of the outline of said model member in a prescribed time period and said wire saw is downwardly movable a prescribed length in a driven condition thereof from a starting position for simultaneously cutting the stone member, said table being subsequently movable to a position wherein said optical sensor is located on the exterior surface of said model member and said carriage is horizontally moved for simultaneously cutting the stone member, said movements being repeated wherein said optical sensor is located at a final position of the exterior surface of said model.