Abstract: A work machine equipped with an automatic hammering function is capable of preventing breakage of the hammer caused by blank firing. Hydraulic oil fed to a hydraulic breaker at the distal end of a work machine is controlled by first and second spools. Operating an operation lever so as to contract single rod type boom cylinders to press the hydraulic breaker against an object to be crushed. Head-side pressure and rod-side pressure of the boom cylinders are respectively detected by pressure sensors. Any one of switches is used to switch the mode of automatic hammering operation between an automatic hammering inhibiting mode and an automatic hammering authorizing mode. In the automatic hammering authorizing mode, a controller controls the first and second spools of the hydraulic breaker so as to open them only when head-side pressure and rod-side pressure of the boom cylinders are in a given range of pressing force.

Abstract: A cobalt coincidence radioactivity detector is used to separate radioactive concrete dust from uncontaminated dust resulting from dismantling a nuclear power plant. A suction air stream carries the dust through a vacuum line to a cyclone segregator. The dust falls into a smaller first container from the segregator, and the detector detects radioactivity in the filled first container. The dust is transferred from the first container to a second container if the detected radioactivity exceeds a predetermined threshold. The dust is transferred from the first container to a third container if the detected radioactivity does not exceed the predetermined threshold. A filter collects the dust carried past the segregator by the suction air stream. If the radioactivity detected in the dust that collects on the filter exceeds the predetermined threshold, the dust in the first container is transferred to the second container before the first container is allowed to fill.

Abstract: A demolition hammer is provided that includes a housing that is reversible and a plurality of interchangeable wear plates. The demolition hammer may include a housing a housing having a first wall and a second wall opposite the first wall, and a power cell disposed within the housing, the power cell having a front face, wherein the housing is reversible such that the housing can be used with the power cell in a first orientation in which the front face faces the first wall and a second orientation in which the front face faces the second wall.

Abstract: Hydraulic hammer ripper for mechanical diggers of the type used to break and pry up hard features in the ground, such as stone, concrete, asphalt or such like and which comprises a tooth (1) attached to the headstock (5) on the mechanical digger by means of an array of attachment items (6) and which consists of, at least, a tooth (1), with its drive devices (2,3) solidly attached to a power accumulator (4) whereby the assembly formed by the tooth (1), drive devices (2,3) and power accumulator (4) is solidly attached to said tooth (1) and mounted on the longitudinal axis (7) of the tooth (1) whereby it is by means of said axis (7) that the striking of the ground is effected by means of the tooth (1) positions of withdrawn (A) and deployed (B).

Abstract: The present invention provides a device for breaking up a paved surface which attaches to a host transport, such as a skid steer or backhoe, having a hydraulic power supply and preferably comprises a closed hydraulic system which includes a regenerative and concentric type double hydraulic cylinder arrangement adjustably supported within a vertical frame. The cylinder is operably attached to a weight such that when fluid is pumped into a first chamber, a piston drives a rod, thereby lifting a weight while at the same time, the piston forces hydraulic fluid from a second chamber to the host. The piston separates the first chamber from the second chamber within the cylinder. Upon reaching a prescribed height, a valve is opened, allowing fluid to flow from the first chamber into the second chamber, thereby allowing the weight to drop rapidly under the influence of gravity.

Abstract: An electrohydraulic pavement breaker system having cavities (28, 30) which are filled with hydraulic fluid (oil) or gas, and which provide mass spring system which is resonant at a frequency which is especially adapted for breaking and rubblizing concrete pavement. The resonant mass (18) is in impacting relationship with the pavement through a shoe (12), which shoe (12) may be part of an assembly which is pivotally mounted on the support structure (10) of the breaker and is vibrated with the mass (18) to repeatedly impact the pavement at the rate of the resonant frequency. An electrohydraulic control system is responsive to the motion and average position of the mass of the vibrator and controls the driving force so as to be at the resonant frequency of the mass spring system and have the amplitude and energy suitable for breaking the pavement.