摘要:
A method and a device for determining the operating time and the operating condition of a hydraulic percussion unit, in particular a hydraulic hammer, having a percussion piston which is guided inside a housing and, under the effect of a controller, alternately performs an operating stroke in an impact direction and a return stroke in a return direction. The method and device obtain information to determine whether the percussion unit requires maintenance operations. Signals are generated during the consecutive, individual operational segments of the percussion unit. The number of signals is proportional to the strokes performed by the percussion piston in one movement direction. The number of the signals is continuously added and is stored as a total number. The current total number of signals can be displayed at least at times for indicating the operating condition of the percussion unit.
摘要:
A fluid-operated percussion device (1) having a percussive piston (3), which alternately executes a work stroke and a return stroke due to the effect of a control. To avoid no-load strikes, in one embodiment of the percussion device (1), the percussive piston (3) is shut down if it has overshot the extended position occurring in normal operation (long- and/or short-stroke operation) by a predetermined distance in the work-stroke direction (arrow 3e) and reached a no-load-strike position. For this purpose, the interior (2d) of the work cylinder (2) that receives the percussive piston (3) additionally has a no load-strike opening (20a), which is connected to the pressure line (8) of the percussion device (1) with an interposed safety element (21) that can be switched between an inoperative position and an operative position.
摘要:
A fluid-powered impact vibrator (5), in particular a hydraulic hammer, comprising a fluid-powered percussion hammer (8) with a percussion piston (18) that is moved back and forth under the effect of a control means (10) and comprising a guide unit (7) on which the percussion hammer is supported, wherein the impact vibrator is additionally provided with a control valve, designed as a pressure monitor, for adaptation to the supplied input power. The control valve preferably is a pressure shut-off valve or a pressure-limiting valve (25) that is connected to the input pressure line (3) provided with the operating pressure, and automatically stops the percussion hammer (8) if the operating pressure resulting from the input power exceeds a specified maximum value. To stop the percussion hammer (8), either the pressure line (3) is blocked or the control means (10) is held in one of its end positions, i.e., the operating stroke or the return stroke positions. Moreover, the pressure shut-off valve or the pressure-limiting valve (25) preferably is a component of the guide unit, consisting of a support frame (7), or the percussion hammer (8) itself.
摘要:
A protective apparatus for preventing the infiltration of contaminants in a fluid-operated percussion device, having a striking tool (3) that is guided to move in a housing (2) and is driven by a percussion piston in the striking direction (arrow 1), and a seal (7) that is supported at least indirectly on the housing (2), on the one hand, and on the striking tool (3), on the other hand, and has a securing segment that is fixedly disposed with respect to either the housing or the striking tool. The seal (7) is disposed between the inner guide portion (5b) of the striking-tool guide and the theoretical striking plane (4) of the percussive piston on the striking tool (3), when seen in the direction opposite the striking direction (arrow 1), such that the countersurface (3e) for the seal, which countersurface moves relative to the securing segment (7a) of the seal (7) and is in contact with the seal, is unaffected by wear.
摘要:
An apparatus for converting measurement signals into digital signals suitable for processing in a microprocessor (12), with the signals having been initiated in a piezo sensor (6) by accelerations acting on the sensor during the impacts of a percussion device (1), particularly a hydraulic hammer, and being used to determine the number of work strokes that have been executed in the impact direction (arrow 3) of the percussion device (1). The conversion apparatus includes: a rectifier (8) that is connected to the output (6a) of the piezo sensor (6) and suppresses the negative component of the measurement signal; a peak-value detector (9) that is connected to the rectifier (8) and converts the remaining, positive component of the measurement signal into an envelope curve; a high-pass filter (10) that causes the envelope curves of consecutive measurement signals to be converted into intermediate signals whose amplitude respectively has a zero passage; and a comparator (11) that is disposed downstream of the high-pass filter (10) and whose output is connected to the digital input (12a) of the microprocessor (12), thereby effecting the conversion of the intermediate signals into digital signals having a rectangular amplitude response.