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.

The hydraulic rotary-percussive hammer drill includes a fluid injection portion including a fluid feed-in inlet and an annular inner groove fluidly connected to the fluid feed-in inlet; a shank including a fluid injection conduit fluidly connected to the annular inner groove; front and rear main sealing gaskets disposed on either side of the annular inner groove and configured to cooperate with a first shank portion of the shank; a rear backup sealing gasket located at the rear of the rear main sealing gasket and configured to cooperate with a second shank portion of the shank; a leakage passage defined between the shank and the fluid injection portion; pressure drop generation means configured to generate pressure drops in the leakage passage when a leakage flow flows in the leakage passage.

The hydraulic rotary-percussive hammer drill includes a fluid injection portion including a fluid feed-in inlet and an annular inner groove fluidly connected to the fluid feed-in inlet; a shank including a fluid injection conduit fluidly connected to the annular inner groove; front and rear main sealing gaskets disposed on either side of the annular inner groove and configured to cooperate with a first shank portion of the shank; a rear backup sealing gasket located at the rear of the rear main sealing gasket and configured to cooperate with a second shank portion of the shank; a leakage passage defined between the shank and the fluid injection portion; pressure drop generation means configured to generate pressure drops in the leakage passage when a leakage flow flows in the leakage passage.

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.

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.

This percussion apparatus includes a body; a tool including a mounting portion slidably mounted in the body; and a striking piston mounted so as to be alternately displaced within the body and configured to strike the mounting portion. The mounting portion of the tool includes an annular retaining rib including a first bearing surface configured to cooperate with a first stop surface provided on the body so as to limit the displacement stroke of the tool towards the striking piston, and a second bearing surface opposite to the first bearing surface and configured to cooperate with a second stop surface provided on the body so as to limit the displacement stroke of the tool opposite to the striking piston and to retain the mounting portion of the tool in the body.

This percussion apparatus includes a body; a tool including a mounting portion slidably mounted in the body; and a striking piston mounted so as to be alternately displaced within the body and configured to strike the mounting portion. The mounting portion of the tool includes an annular retaining rib including a first bearing surface configured to cooperate with a first stop surface provided on the body so as to limit the displacement stroke of the tool towards the striking piston, and a second bearing surface opposite to the first bearing surface and configured to cooperate with a second stop surface provided on the body so as to limit the displacement stroke of the tool opposite to the striking piston and to retain the mounting portion of the tool in the body.

A hydraulic hammer includes a housing configured to receive a housing portion of a tool and a first plurality of rods provided in the housing. The first plurality of rods are configured to engage a first portion of the housing portion of the tool. The first plurality of rods are parallel to a longitudinal axis of the tool. The hydraulic hammer further includes a second plurality of rods provided in the housing. The second plurality of rods are configured to engage a second portion of the housing portion of the tool. The second plurality of rods are parallel to the longitudinal axis of the tool.

A hydraulic hammer includes a housing configured to receive a housing portion of a tool and a first plurality of rods provided in the housing. The first plurality of rods are configured to engage a first portion of the housing portion of the tool. The first plurality of rods are parallel to a longitudinal axis of the tool. The hydraulic hammer further includes a second plurality of rods provided in the housing. The second plurality of rods are configured to engage a second portion of the housing portion of the tool. The second plurality of rods are parallel to the longitudinal axis of the tool.