Abstract: A vacuum-compression type percussion power tool comprises a housing (12), a cylinder (14) fixed in the housing, a piston (16) reciprocating in the cylinder (14) from a reciprocating drive mechanism such as a crank mechanism (18) driven by an electric motor, or any other suitable drive, a working tool (24) installed in the front part of the power tool, and a floating striker (34) which slides inside cylinder (14) in a space between a tail portion (26) of working tool (24) and the lower end of the piston. The power tool has a sealed auxiliary chamber (54, 56) , which is formed by a hollow casing (48) which surrounds the cylinder, and a space below striker (34). The auxiliary chamber is connected to a main working chamber (38), which is formed between the piston and the striker, through a set of compensation holes (44) and a set of idle-stroke holes (46). The power tool has a pumping chamber (27) which is formed in the upper part of cylinder (14) between the upper end face of piston (16) and a closed cover (17).

Abstract: A vacuum-compression type percussion power tool comprising a housing (12), a cylinder (14) fixed in the housing, a piston (16) reciprocating in the cylinder (14) from a reciprocating drive mechanism such as a crank mechanism (18) driven by an electric motor, or any other suitable drive, a working tool (24) installed in the front part of the power tool, and a floating striker (34) which slides inside the cylinder (14) in a space between a tail portion (26) of the working tool (24) and the lower end of the piston.

Abstract: A vacuum-compression type percussion power tool comprising a housing (12), a cylinder (14) fixed in the housing, a piston (16) reciprocating in the cylinder (14) from a reciprocating drive mechanism such as a crank mechanism (18) driven by an electric motor, or any other suitable drive, a working tool (24) installed in the front part of the power tool, and a floating striker (34) which slides inside the cylinder (14) in a space between a tail portion (26) of working tool (24) and the lower end of the piston. The power tool has a sealed auxiliary chamber (54, 56) which is formed by means of a hollow casing (48) which surrounds the cylinder, and a space below the striker (34). The auxiliary chamber is connected to a main working chamber (38), which is formed between the piston and a striker, through a set of compensation holes (44) and a set of idle-stroke holes (46). A check valve (51) is installed in the wall of the auxiliary chamber.