Patent ID: 6601655
Filing Date: 2003-08-05
Classification: B25D,C21B,F27D

Abstract:
A piercing apparatus for executing piercing by back and forth motion comprising:a drifter having a longitudinal interior portion and an outer peripheral portion; a shank rod disposed in the longitudinal interior portion of the drifter; said longitudinal interior portion of the drifter having a front region and a rear region; a forward-blowing unit located in the rear region of the longitudinal interior portion and connected to said shank rod for selective movement of said shank rod forward; a reverse-blowing unit located in the front region of the longitudinal interior portion and connected to said shank rod for selective movement of said shank rod backward; a rotary unit located in the longitudinal interior portion of the drifter between the front region and the rear region and connected to the shank rod for selective rotation of the shank rod; a hydraulic pressure feed unit hydraulically connected to the forward-blowing unit and the reverse-blowing unit; a pilot valve unit mounted on the outer peripheral portion of the drifter and connected to the hydraulic pressure feed unit for selectively changing hydraulic pressure to the forward-blowing unit for selective movement of the shank rod forward and the reverse-blowing unit for selective movement of the shank rod backward.