A hydraulic hammer includes a housing defining a cutout and a power cell slidably received within the housing. The power cell includes a valve assembly extending from a side of the power cell. The valve assembly is at least partially received within the cutout of the housing. The hydraulic hammer further includes a pair of wear plates at least partially disposed around the valve assembly of the power cell. Each of the pair of wear plates is coupled to at least one of the power cell and the housing.

A hydraulic hammer includes a housing defining a cutout and a power cell slidably received within the housing. The power cell includes a valve assembly extending from a side of the power cell. The valve assembly is at least partially received within the cutout of the housing. The hydraulic hammer further includes a pair of wear plates at least partially disposed around the valve assembly of the power cell. Each of the pair of wear plates is coupled to at least one of the power cell and the housing.

The invention concerns a rock breaking device comprising a striking cell having at least one actuation chamber, a striking piston, and a hydraulic circuit comprising a hydraulic supply source having a High Pressure circuit and a Low Pressure circuit, and an actuator configured to connect the High Pressure circuit or the Low Pressure circuit to the actuation chamber so as to move the piston in translation in the striking cell in a normal movement area of which the limits are variable depending on the pressure difference between the High Pressure circuit and the Low Pressure circuit, the striking cell comprising depressurizing means configured to control the establishment of hydraulic communication between the High Pressure circuit and the Low Pressure circuit when the striking piston exits a predefined movement area.

The invention concerns a rock breaking device comprising a striking cell having at least one actuation chamber, a striking piston, and a hydraulic circuit comprising a hydraulic supply source having a High Pressure circuit and a Low Pressure circuit, and an actuator configured to connect the High Pressure circuit or the Low Pressure circuit to the actuation chamber so as to move the piston in translation in the striking cell in a normal movement area of which the limits are variable depending on the pressure difference between the High Pressure circuit and the Low Pressure circuit, the striking cell comprising depressurizing means configured to control the establishment of hydraulic communication between the High Pressure circuit and the Low Pressure circuit when the striking piston exits a predefined movement area.

A bi-directional valve body for a pneumatic hammer is provided which has non-circular air intake and air exhaust ports within lateral walls of the valve body and which provides for a smaller mass and volume while increasing the efficiency of air flow through the valve body. A length of the valve body is greater than a width, and allows for less resistance of air flow into the lateral walls defined within the respective valve body halves.

A bi-directional valve body for a pneumatic hammer is provided which has non-circular air intake and air exhaust ports within lateral walls of the valve body and which provides for a smaller mass and volume while increasing the efficiency of air flow through the valve body. A length of the valve body is greater than a width, and allows for less resistance of air flow into the lateral walls defined within the respective valve body halves.

A hydraulic hammering device enables an auto-stroke mechanism and an idle strike prevention mechanism to coexist with a simple circuit configuration. The device includes a first control valve to control advancing and retracting movements of a piston, an auto-stroke mechanism and an idle strike prevention mechanism, and a second control valve to select either of the auto-stroke mechanism and the idle strike prevention mechanism. To the second control valve, a shared spool is slidably fitted and a mode selection means is disposed. When the mode selection means allows supply of pressurized oil to an auto-stroke setting portion of the shared spool and prohibits discharge of pressurized oil from an idle strike prevention setting portion, the auto-stroke mechanism is selected. When prohibiting supply of pressurized oil to the auto-stroke setting portion and allowing discharge of pressurized oil from the idle strike prevention setting portion, the idle strike prevention mechanism is selected.

A hydraulic hammering device enables an auto-stroke mechanism and an idle strike prevention mechanism to coexist with a simple circuit configuration. The device includes a first control valve to control advancing and retracting movements of a piston, an auto-stroke mechanism and an idle strike prevention mechanism, and a second control valve to select either of the auto-stroke mechanism and the idle strike prevention mechanism. To the second control valve, a shared spool is slidably fitted and a mode selection means is disposed. When the mode selection means allows supply of pressurized oil to an auto-stroke setting portion of the shared spool and prohibits discharge of pressurized oil from an idle strike prevention setting portion, the auto-stroke mechanism is selected. When prohibiting supply of pressurized oil to the auto-stroke setting portion and allowing discharge of pressurized oil from the idle strike prevention setting portion, the idle strike prevention mechanism is selected.

A fluid pressure hitting device comprises a piston inserted in a cylinder, a chisel, and a first, second, and third chambers. The chisel is fitted in the cylinder such that a part of the chisel projects from one axial end of the cylinder and is configured to further project from that axial end due to being hit by the piston as the piston slides toward the one axial end. The first through third chambers are partitioned by an inner peripheral surface of the cylinder and an outer peripheral surface of the piston. The first through third chambers are arranged in the axial direction in order fluid the one axial end to another axial end of the cylinder. A flow path is configured to supply fluid from a fluid supply portion when the piston hits the chisel, to the first chamber.

A fluid pressure hitting device comprises a piston inserted in a cylinder, a chisel, and a first, second, and third chambers. The chisel is fitted in the cylinder such that a part of the chisel projects from one axial end of the cylinder and is configured to further project from that axial end due to being hit by the piston as the piston slides toward the one axial end. The first through third chambers are partitioned by an inner peripheral surface of the cylinder and an outer peripheral surface of the piston. The first through third chambers are arranged in the axial direction in order fluid the one axial end to another axial end of the cylinder. A flow path is configured to supply fluid from a fluid supply portion when the piston hits the chisel, to the first chamber.