HAMMER BIT OF AN EXCAVATOR CAPABLE OF IMPROVING EXCAVATION EFFICIENCY AND ECONOMICAL EFFICIENCY BY COMPOSING OF A MAIN BIT AND AN EXTERNAL BIT

摘要

PURPOSE: A hammer bit of an excavator is provided to heighten the efficiency on excavation by composing a bit with a main bit and an external bit and the economical effect by reducing the period and cost for repair by recycling an external pipe only without replacing the whole bit. CONSTITUTION: The hammer bit of an excavator contains a back head(10) taking high-pressure compressed air from the outside, a housing(20) installed on the lower part of the back head(10), a screw(21) installed on the outside of the housing(20), an inner sleeve(22) installed in the housing(20), a check valve(30) and a rigid valve(40) installed on the lower part of the inner sleeve(22) to control compressed air, a piston(50) reciprocated by the compressed air supplied from the outside, a hood valve(60) and a bit(100) which transfers impact force to bedrock using the impact force of the piston installed on the lower part of the piston(50) and coupled to the housing(20) using a chuck(80). The bit(100) is formed in a two-stage split bit composed of a main bit(100) and an external bit(110).