The rotary-percussive hydraulic perforator includes a body; a shank; a striking piston configured to strike the shank and provided with a braking surface; a braking chamber configured to hydraulically brake the striking piston; a stop piston configured to apply a pushing force on the shank and provided with a bearing surface configured to abut against a stop surface provided on the body, so as to limit the stroke of displacement of the stop piston towards the shank. The rotary-percussive hydraulic perforator is configured such that the bearing surface and the stop surface are axially spaced apart by a predetermined spacing distance simultaneously when (i) the shank bears on the stop piston and is in contact with the striking piston, and (ii) the braking surface is located at an inlet edge of the braking chamber.

The objective of the present invention is to provide a hydraulic breaker comprising: a hydraulic breaker body part; a sensor part sensing vibration generated in the hydraulic breaker body part when objects to be crushed, including bedrocks, are crushed, so as to output a sensing signal; and a control part receiving the sensing signal so as to calculate the time for which the hydraulic breaker body part vibrates, thereby calculating an operating time.

A hydraulic hammering device enables an auto-stroke mode and an idle strike prevention mode 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 mode and an idle strike prevention mode, and a second control valve to select either of the auto-stroke mode or the idle strike prevention mode. 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 mode 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 mode is selected.

A hydraulic hammering device enables an auto-stroke mode and an idle strike prevention mode 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 mode and an idle strike prevention mode, and a second control valve to select either of the auto-stroke mode or the idle strike prevention mode. 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 mode 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 mode is selected.

Provided is a hydraulic hammering device having improved hammering efficiency and of low cost. A piston has a valve switching groove between large-diameter sections thereof. A cylinder has three control ports at positions corresponding to the valve switching groove. A switching valve mechanism has a valve presser for always pressing a valve in one direction and also has a valve controller for moving, when supplying pressurized oil, the valve in the opposite direction against the pressing force of the valve presser. A valve control port communicates with the valve controller so as to supply the pressurized oil to the valve controller and is separated from a piston front chamber and a piston rear chamber. Only either a piston retraction control port or a piston advance control port communicates with the valve control port depending on advance or retraction of the valve switching groove.

Provided is a hydraulic hammering device having improved hammering efficiency and of low cost. A piston has a valve switching groove between large-diameter sections thereof. A cylinder has three control ports at positions corresponding to the valve switching groove. A switching valve mechanism has a valve presser for always pressing a valve in one direction and also has a valve controller for moving, when supplying pressurized oil, the valve in the opposite direction against the pressing force of the valve presser. A valve control port communicates with the valve controller so as to supply the pressurized oil to the valve controller and is separated from a piston front chamber and a piston rear chamber. Only either a piston retraction control port or a piston advance control port communicates with the valve control port depending on advance or retraction of the valve switching groove.

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.

An apparatus for generating impulse-dynamic process forces includes a pressure chamber, a connecting chamber and a bolt chamber The pressure chamber includes a plunger arranged to be pushed into the pressure chamber for compression of a hydraulic medium 1ocated therein. In the connecting chamber there is displaceably arranged a stepped pistons which has a valve body for closing an orifice connecting the pressure chamber to the connecting chamber. In the bolt chamber there is located a displaceable impact bolt which has a first bolt portion and a second bolt portion The first bolt portion seals an interior space of the bolt chamber that surrounds the second bolt portion. Connected to the bolt chamber there is at least one pressure reservoir containing pressurised pressure medium, which pressure reservoir is in communicating connection via a connection port with the interior space of the bolt chamber.

An apparatus for generating impulse-dynamic process forces includes a pressure chamber, a connecting chamber and a bolt chamber The pressure chamber includes a plunger arranged to be pushed into the pressure chamber for compression of a hydraulic medium 1ocated therein. In the connecting chamber there is displaceably arranged a stepped pistons which has a valve body for closing an orifice connecting the pressure chamber to the connecting chamber. In the bolt chamber there is located a displaceable impact bolt which has a first bolt portion and a second bolt portion The first bolt portion seals an interior space of the bolt chamber that surrounds the second bolt portion. Connected to the bolt chamber there is at least one pressure reservoir containing pressurised pressure medium, which pressure reservoir is in communicating connection via a connection port with the interior space of the bolt chamber.