The percussion apparatus includes a striking piston and a piloting device configured to make a striking stroke of the striking piston vary, the piloting device comprising a piloting cylinder, a piloting slide mounted movable in translation within the piloting cylinder according to a direction of displacement and mounted movable in rotation within the piloting cylinder, and a main piloting chamber delimited by the piloting slide and the piloting cylinder. The percussion apparatus further includes a setting device configured to set a range of variation of the striking stroke of the striking piston, the setting device including a setting member configured to set the angular position of the piloting slide in the piloting cylinder, and at least one fluidic communication passage formed on the piloting slide and configured to hydraulically limit the translational displacement stroke of the piloting slide according to the direction of displacement according to the angular position occupied by the piloting slide.

The percussion apparatus includes a striking piston and a piloting device configured to make a striking stroke of the striking piston vary, the piloting device comprising a piloting cylinder, a piloting slide mounted movable in translation within the piloting cylinder according to a direction of displacement and mounted movable in rotation within the piloting cylinder, and a main piloting chamber delimited by the piloting slide and the piloting cylinder. The percussion apparatus further includes a setting device configured to set a range of variation of the striking stroke of the striking piston, the setting device including a setting member configured to set the angular position of the piloting slide in the piloting cylinder, and at least one fluidic communication passage formed on the piloting slide and configured to hydraulically limit the translational displacement stroke of the piloting slide according to the direction of displacement according to the angular position occupied by the piloting slide.

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.

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 valve of a pneumatic hammer include a rear mechanism including two opposite inlets, a chamber member, outlets, a relief chamber communicating with the outlets, two opposite inlet channels disposed externally of the chamber member, and two first outlet tunnels disposed externally of the chamber member wherein one end of the relief chamber communicates with the first outlet tunnels, the first outlet tunnels are disposed externally of the relief chamber and pass through the rear mechanism, and the inlets communicate with the inlet channels and the outlets; a front mechanism including a chamber element communicating with the inlet channels, an axial tunnel through a center of the chamber element, and two second outlet tunnels disposed externally of the chamber element, the second outlet tunnels corresponding to and communicating with the first outlet tunnels; and a disc between the chamber member and the chamber element.

A pneumatic hammer includes a piston in an operating cylinder; and a valve mounted at a rear end of the operating cylinder and including a front mechanism, a rear mechanism, and a disc. The rear mechanism includes two opposite inlets, a chamber member, outlets, a relief chamber communicating with the outlets, two opposite inlet channels disposed externally of the chamber member, and two first outlet tunnels disposed externally of the chamber member. The front mechanism includes a chamber element on one surface communicating with the inlet channels, an axial tunnel through a center of the chamber element, and two second outlet tunnels disposed externally of the chamber element. The disc is between the chamber member and the chamber element. The operating cylinder includes intermediate through holes and two inlet passageways having one ends communicating with the axial space and the other ends communicating with the second outlet tunnels.

Provided is a two-piston hydraulic striking device that has stable operatively. This two-piston hydraulic striking device includes two striking mechanisms for striking one transfer member. Each striking mechanism has a pressure receiving area ratio between the front and rear of a piston thereof set in such a way that the two striking mechanisms have the same cycle time.

A hydraulic striking device that is mounted on construction equipment such as an excavator and breaks solid rocks in the grounds using a rod that is hit by a piston is proposed. Particularly, a hydraulic striking device that can automatically switch stroke modes by sensing the intensity of pressure of an upper chamber formed at an upper portion between a piston and a cylinder in accordance with the statuses of rocks in the ground is proposed.

A hydraulic percussion device comprising a piston mounted for reciprocal motion within a cylinder to impact a percussion bit and a control valve to control reciprocation of the piston. A valve pilot line is arranged to switch the control valve based on the position of the piston within the cylinder, wherein the valve pilot line is alternately connected, by the reciprocal movement of the piston, to high and low pressure lines (P, T) via an undercut in the piston. The undercut is located at a portion of the piston having a diameter less than the maximum sealing diameter of the piston.

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.