Patent ID: 7603977

Claim:
A cooling channel piston for an internal combustion engine, comprising: a piston head forged from steel, said piston head comprising: (a) a combustion bowl in a piston crown; (b) a ring wall with ring belt; and (c) a cooling channel that runs on a circumference of the piston head at a height of the ring belt and having a plurality of bores distributed over a circumference of the cooling channel, said bores being directed towards the piston crown; a cover for closing off the cooling channel; pin bosses suspended on the piston head; a piston skirt connected with the pin bosses; and liquid-filled heat pipes, each pipe having an evaporator side and condenser side, said pipes being disposed in the bores of the cooling channel, wherein the evaporator sides of the heat pipes end at a piston-crown-side end of the bores, and the condenser sides of the heat pipes end in the cooling channel, and wherein the bores have a bore depth (B T ) that ends before the piston crown, so that a wall ridge of piston material exists between the evaporator sides of the heat pipes and the piston crown.