Heavy-duty material processors (e.g., shears, concrete crushers) include a jaw that pivotally connects to another jaw. A hydraulic cylinder extends between the jaws to open and close the jaws in a shearing motion. Cutting/shearing/crushing blade inserts mount to detachable blade holders, which in turn mount to one of the jaws. Wedge blocks securely and detachably attach the blade inserts to the remainder of their associated jaw, and rely on force-amplifying wedge surfaces to ensure a secure attachment. The detachable blade holders may include lateral flanges that extend across an otherwise exposed face of their respective underlying jaw bodies to protect the jaw bodies during use. A blade on one of the jaws is laterally adjustable, which helps to free a jam if one of the jaws gets jammed into the space between blades in the other jaw.

A hydraulic power tool includes a housing defining a cylinder, a piston at least partially positioned within the cylinder and movable between a retracted position and an extended position, a reservoir containing hydraulic fluid, a pump for transferring hydraulic fluid in the reservoir to the cylinder, causing the piston to move from the retracted position toward the extended position, a return valve defining a rotational axis and positioned between the cylinder and the reservoir, and a valve actuator driven by the pump for opening the return valve, thereby fluidly communicating the cylinder and the reservoir, in response to a predetermined pressure being reached in the cylinder.

A hydraulic power tool includes a housing defining a cylinder, a piston at least partially positioned within the cylinder and movable between a retracted position and an extended position, a reservoir containing hydraulic fluid, a pump for transferring hydraulic fluid in the reservoir to the cylinder, causing the piston to move from the retracted position toward the extended position, a return valve defining a rotational axis and positioned between the cylinder and the reservoir, and a valve actuator driven by the pump for opening the return valve, thereby fluidly communicating the cylinder and the reservoir, in response to a predetermined pressure being reached in the cylinder.

The present invention relates to a hydraulic tool including a working unit, a driving unit, a connection unit, and a switching device. The working unit is adapted to operate a workpiece. The driving unit is configured to drive the working unit and comprises a housing and a movable part provided in the housing and movable between an initial position and an end position. The connection unit connects the working unit and the driving unit. The switching device can rotate between a first position and a second position. When the switching device is in the first position, the movable part of the driving unit has a first stroke from the initial position to the end position; when the switching device is in the second position, the movable part of the driving unit has a second stroke smaller than the first stroke.

A portable, hand held hydraulic cutting tool having an in-line handle assembly and a working head assembly. The handle assembly has a tool frame portion and a neck portion. The working head assembly has a pair of jaw members joined so that they are movable relative to each other and held in place by a locking pin. Each jaw member has a cutting blade attached thereto. Each jaw member can be tapered and can include weight reducing pockets defined in respective sidewalls. Each jaw member includes a raised tab on an outside edge that mates with a respective tab notch in a yoke of the neck portion of the handle assembly. When the locking pin is in an extended position, the jaw members of the tool can separate and rotate away from one another until their respective locking tabs engage their respective locking tab opening, connecting the jaw members to the yoke of the neck portion of the handle assembly.

Embodiments of the invention provide a ram assembly for a hydraulic tool. The ram assembly includes a ram piston having a ram cavity. The ram piston receives a hydraulic pressure reaction force. The ram assembly further includes an overload assembly disposed in the ram cavity or in a cavity defined by a manifold. The overload assembly includes a burst disc positioned at a first end of the ram cavity or manifold, a lock nut positioned at a second end of the ram cavity or manifold, and a spacer positioned between the burst disc and the lock nut. The spacer transfers a supporting force applied to the lock nut to the burst disc. The hydraulic pressure reaction force and the supporting force both act in the same direction, and thus, are additive forces acting on the burst disk.

A hydraulic actuation device includes a tool, an actuation part having a pressure oil supply mechanism configured to send pressure oil from an oil chamber to the tool and return return oil from the tool to the oil chamber, an operation handle for adjusting oil passages for the pressure oil and the return oil in the pressure oil supply mechanism and configured to be able to be moved from an initial position, and biasing means configured to bias the operation handle toward the initial position when no external force is applied to the operation handle. When the operation handle moves from the initial position, the tool is actuated by the actuation part. When the operation handle is returned to the initial position by the biasing means, operation of the tool by the actuation part is stopped.

A hydraulic actuation device includes a tool, an actuation part having a pressure oil supply mechanism configured to send pressure oil from an oil chamber to the tool and return return oil from the tool to the oil chamber, an operation handle for adjusting oil passages for the pressure oil and the return oil in the pressure oil supply mechanism and configured to be able to be moved from an initial position, and biasing means configured to bias the operation handle toward the initial position when no external force is applied to the operation handle. When the operation handle moves from the initial position, the tool is actuated by the actuation part. When the operation handle is returned to the initial position by the biasing means, operation of the tool by the actuation part is stopped.

A hydraulic actuator includes a tool unit (10) having a tool that operates by pressurized oil generated by a hydraulic pump (40), a driving unit (60) that generates a rotation torque, and a torque transmission coupler (70) to one end of which the tool unit (10) is detachably attachable and to other end of which the driving unit (60) is detachably attachable and that transmits the rotation torque generated by the driving unit (60) to a rotatable member (41) of the tool unit (10). The torque transmission coupler (70) includes a flexible rod-like shaft (74) and a flexible cover (72) that surrounds an outer peripheral surface of the shaft. The torque transmission coupler (70) is bendable as the shaft (74) and the cover (72) have flexibility.

A hydraulic tool cutting dies including first and second cutting dies. The first cutting die has a first mounting section and a first cutting edge. The first mounting section is sized and shaped to removably attached to a hydraulic tool. The second cutting die has a second mounting section and a second cutting edge. The second mounting section is sized and shaped to removably attached to the hydraulic tool. The first cutting die includes a post extending past the first cutting edge and the second cutting die includes a post receiving area which has a different cross-sectional shape than the post.