Method for producing hollow piston for compressor by forging

A method of producing a hollow piston for a compressor, the piston including at least one head portion which is slidably fitted in a cylinder bore of the compressor and an engaging portion which engages a reciprocating drive device of the compressor for reciprocating the piston, at least said at least one head portion being hollow, said method comprising the steps of:

• placing a forging blank between two first dies;
• moving said two first dies relatively toward each other along a first axis while moving at least one second die from a retracted position toward an advanced position along a second axis which is perpendicular to said first axis;
• moving said two first dies relatively away from each other and moving said at least one second die from said advanced position to said retracted position so that a piston blank which has been forged is removed, said piston blank including an engaging-portion-forming section which provides said engaging portion of the piston, and at least one head-portion-forming section which provides at least a part of said at least one head portion of the piston;
• and
• fixing a closing member to said at least one head-portion-forming section of said piston blank so as to provide the piston.

A method of producing a piston blank for at least one hollow piston used for a compressor, the piston including at least one head portion which is slidably fitted in a cylinder bore of the compressor and an engaging portion which engages a reciprocating drive device of the compressor for reciprocating the piston, at least said at least one head portion being hollow, said method comprising the steps of:

• placing a forging blank between two first dies;
• moving said two first dies relatively toward each other along a first axis;
• moving at least one second die from a retracted position toward an advanced position along a second axis which is perpendicular to said first axis;
• and
• moving said two first dies relatively away from each other and moving said at least one second die from said advanced position to said retracted position so that a piston blank which has been forged is removed, said piston blank including an engaging-portion-forming section which provides said engaging portion of the piston, and at least one head-portion-forming section which provides at least a part of said at least one head portion of the piston.

A method of producing a piston blank for at least one hollow piston used for a compressor, the piston including at least one head portion which is slidably fitted in a cylinder bore of the compressor and an engaging portion which engages a reciprocating drive device of the compressor for reciprocating the piston, at least said at least one head portion being hollow, said method comprising the steps of:

• placing a forging blank between two first dies;
• moving said two first dies relatively toward each other along a first axis while moving at least one second die from a retracted position toward an advanced position along a second axis which is perpendicular to said first axis;
• and
• moving said two first dies relatively away from each other and moving said at least one second die from said advanced position to said retracted position so that a piston blank which has been forged is removed, said piston blank including an engaging-portion-forming section which provides said engaging portion of the piston, and at least one head-portion-forming section which provides at least a part of said at least one head portion of the piston.