A pneumatic hammer has a handle, a body, a valve seat, a cylinder device, an assembling device, and a chisel. The body is transversally connected to the handle and has a chamber. The valve seat is mounted in the chamber of the body and has a rear valve, a front valve, and a valve plate disposed between the rear valve and the front valve. The cylinder device is mounted in the chamber, abuts against the valve seat, and has a cylinder barrel and a hammer. The cylinder barrel is mounted in the chamber and has a cylinder chamber. The hammer is movably disposed in the cylinder chamber. The assembling device is connected to the cylinder device, and has a mounting jacket, an engaging element, multiple positioning elements, a spring, and an engaging ring. The chisel is detachably connected to the assembling device, and is inserted into the cylinder chamber.

This percussion apparatus includes a striking piston, a control distributor arranged to control a reciprocating movement of the striking piston, and a control device arranged to vary the striking stroke of the striking piston. The control device comprises a plurality of control channels, a control channel connected to the control distributor, a control slide movably mounted between a plurality of control positions, and an adjusting slide mounted in a receiving housing delimited by the control slide, the control slide and the adjusting slide delimiting a first adjusting chamber connected to the control channel and a second adjusting chamber connected to a the high-pressure fluid supply circuit. The control slide is movably mounted between a first position in which the first control chamber and the second adjusting chamber are connected and a second position in which the first control chamber and the second adjusting chamber are isolated.

This percussion apparatus includes a striking piston, a control distributor arranged to control a reciprocating movement of the striking piston, and a control device arranged to vary the striking stroke of the striking piston. The control device comprises a plurality of control channels, a control channel connected to the control distributor, a control slide movably mounted between a plurality of control positions, and an adjusting slide mounted in a receiving housing delimited by the control slide, the control slide and the adjusting slide delimiting a first adjusting chamber connected to the control channel and a second adjusting chamber connected to a the high-pressure fluid supply circuit. The control slide is movably mounted between a first position in which the first control chamber and the second adjusting chamber are connected and a second position in which the first control chamber and the second adjusting chamber are isolated.

A hydraulic hammer is disclosed having a piston and an accumulator membrane disposed external and co-axial to the piston. Additionally, a sleeve is disposed between the piston and accumulator membrane, wherein the sleeve has a plurality of radial passages formed therein that fluidly connect the accumulator membrane with the piston.

A hydraulic hammer is disclosed having a piston and an accumulator membrane disposed external and co-axial to the piston. Additionally, a sleeve is disposed between the piston and accumulator membrane, wherein the sleeve has a plurality of radial passages formed therein that fluidly connect the accumulator membrane with the piston.

A hydraulic hammer including a housing, a piston arranged for reciprocating movement within the housing, a hydraulic circuit within the housing. The hydraulic circuit is configured for connection to a source of pressurized fluid. The hydraulic circuit includes an inlet passage configured to provide a hydraulic fluid to the piston, an outlet passage configured to provide a return flow path for the hydraulic fluid from the piston a bypass passage selectively connecting the inlet passage to the outlet passage and a thermostatic valve assembly configured to connect the inlet passage to the piston when the temperature of the hydraulic fluid is below a threshold temperature and connect the inlet passage to the bypass passage when the temperature of the hydraulic fluid is above the threshold temperature.

A hydraulic hammer including a housing, a piston arranged for reciprocating movement within the housing, a hydraulic circuit within the housing. The hydraulic circuit is configured for connection to a source of pressurized fluid. The hydraulic circuit includes an inlet passage configured to provide a hydraulic fluid to the piston, an outlet passage configured to provide a return flow path for the hydraulic fluid from the piston a bypass passage selectively connecting the inlet passage to the outlet passage and a thermostatic valve assembly configured to connect the inlet passage to the piston when the temperature of the hydraulic fluid is below a threshold temperature and connect the inlet passage to the bypass passage when the temperature of the hydraulic fluid is above the threshold temperature.

A valve of a hydraulically striking device having a housing, the housing comprising a moving member being seated inside the housing to move in a reciprocating manner by means of a hydraulic fluid. The moving member has an inner space, the valve has a return space and a pressure space provided, in the axial direction, at a distance from one another on the inner surface of the housing facing the moving member, wherein the rest of the inner surface of the housing in the same axial positions of the return space and the pressure space forms guide surfaces that are concentric with the moving member and against the moving member for centering the moving member.

A valve of a hydraulically striking device having a housing, the housing comprising a moving member being seated inside the housing to move in a reciprocating manner by means of a hydraulic fluid. The moving member has an inner space, the valve has a return space and a pressure space provided, in the axial direction, at a distance from one another on the inner surface of the housing facing the moving member, wherein the rest of the inner surface of the housing in the same axial positions of the return space and the pressure space forms guide surfaces that are concentric with the moving member and against the moving member for centering the moving member.

A hydraulic hammering device that uses a scheme in which a front chamber is switched into communication with a low-pressure circuit when a piston advances, wherein occurrences of galling to the piston at a sliding contact portion with a front-chamber liner is reduced. The front chamber has the front-chamber liner fitted to an inner surface of a cylinder. A hydraulic chamber space communicating with the front chamber and filled with hydraulic oil is formed as a cushion chamber on the inner peripheral surface of a rear portion of the front-chamber liner. The cushion chamber has a second drain circuit (from first end face grooves to slits to second end face grooves), which is provided separately from a drain circuit that guides the hydraulic fluid passing through a liner bearing of the front-chamber liner to the low-pressure circuit.