Abstract: A manhole cover assembly includes a manhole cover and a latch assembly. The manhole cover is supportable by a seat of a manhole frame. The latch assembly includes a latch housing fixedly coupled to the manhole cover. A latch plunger is slidably coupled to the latch housing. The latch plunger includes a follower arm. A latch lever is rotatably coupled to the latch housing. The latch lever includes a stop. The latch lever is rotatable relative to the latch housing between a locked position and an unlocked position. The stop is structured to engage the manhole frame when the latch lever is rotated to unlocked position so as to force the manhole cover away from the frame.

Abstract: The invention relates to an apparatus for actuating of processing machines like metal forming machines and method, control and application of an apparatus for actuating said metal forming machines. The processing machine is driven by at least two rams with pressurized fluid, like water, whereas the rams are actuated by variable pumps with different fluid under pressure, e.g. hydraulic liquid.

Abstract: A hydraulic cylinder is provided which allows for a mount plate, or the like, to be moved between three positions. The mount plate can be positively positioned in any one of three different positions by appropriately supplying or removing pressurized hydraulic fluid to hydraulic fluid ports on the cylinder. The provision of appropriate positive stops corresponding to each desired position avoids the necessity for complex and/or expensive hydraulic control mechanisms. The cylinder is believed to be particularly suited for performing piercing operations, involving a negative pierce, in hydro-forming operations.

Abstract: The invention relates to a method for adjusting the position of a mandrel (10), which is situated in a hydraulic punch consisting of a cylinder and a ram that form a mandrel cylinder (8), in an extrusion press for producing pipes (2), which are extruded from blocks (4) that are loaded into a receiving device (5) situated upstream of the extrusion press (3) and are punched using the mandrel (10). The invention is characterised in that the mandrel cylinder (8) is driven directly by pumps (11), which are set for a pre-calculated throughput that is dependent on the press speed, and that an additional throughput is added to the pre-calculated pump throughput. To adjust the position of the mandrel (10), a control valve (16) that acts on the ring side (12) of the mandrel (8) is connected to a tank (17).

Abstract: An improved method and apparatus are provided for constructing and operating a linear actuator, and equipment incorporating a linear actuator, by operatively connecting a pressure biasing pneumatic arrangement between the driving member and the driven member of a mechanical linear actuator for applying a unidirectional biasing force between the driving and driven members, along an axis of motion, regardless of the location or movement of the driving and driven elements with respect to one another along the axis of motion. The pneumatic biasing arrangement is also configured, connected and operated to reduce the force which must be exerted by the driving and driven members in extending and retracting the linear actuator. The pneumatic biasing arrangement may further be configured for preferentially aiding extension or retraction of the actuator.

Abstract: A device for controlling the drawing process in a transfer press has two tool parts which act in opposition to one another and between which the workpiece to be deformed is held. One tool part is moved between two reversal points by a mechanical crank mechanism driven at a constant rotational speed. The second tool part is connected to the piston of a hydraulic differential cylinder via a piston rod. The movement of the piston is controlled by the supply of pressure medium into a first chamber and by the discharge of pressure medium out of the second chamber of the differential cylinder. During a first time segment within a range delimited by the first and the second reversal point, the rod-side face of the piston is acted upon by a pressure which is sufficiently high to accelerate the second tool part as that, when the two tool parts impinge one onto the other, both tool parts move virtually at the same speed.

Abstract: An adjusting cylinder for long, rapid lifting movements in rolling stands, includes vertical edging stands, wherein each cylinder has at least one piston, which acts through the bearing chocks of at least one work roll or of an interposed roll to adjust a work roll on both sides, wherein each adjusting cylinder has a piston that is equipped with two oppositely directed piston rods, and each piston is inserted in a recess in the cylinder base or cylinder cover, such that the base and cover have coaxially arranged bores through which the piston rods pass. The surface formed by one piston and the piston rod is smaller than the surface formed by another piston and the piston rod.

Abstract: The invention relates to an electrohydraulic pressing device (1) that can be operated using one hand. The device comprises a working head (30), an electric motor (4), a pump (20), a hydraulic reservoir (33), and a gear mechanism (19) extending between the electric motor (4) and the pump (20). A holding area (5) around which a hand is placed is provided and an actuating switch (39) is assigned to this area. The aim of the invention is to improve a pressing device of this type with regard to the handling thereof. To this end, the invention provides that the holding area (5) is formed around the electric motor (4), and the actuating switch (39) is situated between the electric motor (4) and the working head.

Abstract: A forging device includes a die having an axis extending generally vertically. A work is placed in the die along the axis. First and second punches extend coaxially with the die and can interpose the work therebetween. A pressurizing section pressurizes the first and second punches toward the work generally simultaneously.

Abstract: While a workpiece is heated and pressed by one of a pair of high-pressure vessels, a workpiece being pressed by the other high-pressure vessel is placed in a heated state. In the reducing process after termination of heating and pressing treatment of the workpiece by one high-pressure vessel, both the high-pressure vessels are placed in communication, and the pressure medium gas released from one high-pressure vessel is poured into the other high-pressure vessel. After pressures of both the high-pressure vessels have assumed a nearly balanced state, the pressure medium gas is sucked out of one high-pressure vessel by a compressor and pressed, and is poured into the other high-pressure vessel, and the workpiece is heated and pressed by the other high-pressure vessel. By the method as described, considerable shortening of cycle time of HIP treatment is achieved, and the HIP treatment can be carried out with high efficiency.

Abstract: The invention describes a production machine (1), in particular an edging press (2), preferably for shaping sheet metal parts (3) for making housing parts, sections (4), etc, with a machine frame (5) having C-shaped supporting side plates (6, 7) and at least one wall part (13) spacing the supporting side walls (6, 7) at a distance (11) apart from one another and permanently joined thereto. Mounted on the machine frame (5) so as to be non-displaceable is a press beam (15) on which a bending tool (36) can be mounted. Lying opposite it is another press beam (16), on which a bending tool (37) can also be mounted, displaceable in a guide arrangement (30) of the machine frame (5) by means of a drive arrangement (27). An actuator drive (25, 26) drivingly connected to the displaceable press beam (16) is preferably provided respectively on opposing side faces (22, 23) of each of the supporting side walls (6, 7).

Abstract: A hemming machine is disclosed having a base, a nest adapted to support a part to be hemmed, a nest carrier which supports the nest and in which both the nest and nest carrier are vertically movably mounted to the base. At least one hemming die is laterally slidably mounted to the base and movable between an extended position in which the die overlies a portion of the nest, and a retracted position in which the die is spaced laterally outwardly from the nest. A lock unit selectively locks the nest carrier against vertical movement relative to the base in at least one, and preferably two positions, so that, with the nest carrier locked against movement relative to the base, inflation of a hydraulic bladder sandwiched between the nest and nest carrier displaces the nest vertically upwardly from the carrier so that the part carried by the nest is compressed against the hemming dies and performs the hemming operation.

Abstract: A hemming machine is disclosed having a base, a nest adapted to support a part to be hemmed, a nest carrier which supports the nest and in which both the nest and nest carrier are vertically movably mounted to the base. At least one hemming die is laterally slidably mounted to the base and movable between an extended position in which the die overlies a portion of the nest, and a retracted position in which the die is spaced laterally outwardly from the nest. A lock unit selectively locks the nest carrier against vertical movement relative to the base in at least one, and preferably two positions, so that, with the nest carrier locked against movement relative to the base, inflation of a hydraulic bladder sandwiched between the nest and nest carrier displaces the nest vertically upwardly from the carrier so that the part carried by the nest is compressed against the hemming dies and performs the hemming operation.

Abstract: A drive system for the container holder and the travelling beam of a metal extruder press in which a return stroke is accelerated by connecting the annular chambers of the travelling beam and container holder cylinders to a pressurization force and with the full piston area chambers of the container holder connected to a tank, connecting the full piston area chambers of the travelling beam to the pressure source as well.

Abstract: A press has a fixed platen, a movable platen displaceable toward and away from the fixed platen, a plurality of low-pressure cylinders braced against the movable platen and pressurizable to move it toward the fixed platen, and a plurality of medium-pressure cylinders braced against the movable platen and pressurizable to move it toward the fixed platen. A low-pressure accumulator holding a body of hydraulic fluid and a head of nitrogen and a medium-pressure accumulator holding a body of hydraulic fluid and a head of nitrogen are connected via respective conduits with the low- and medium-pressure cylinders. a nitrogen supply connects the accumulators above the respective fluid bodies together in a closed system. A controller feeds the fluid therefrom to the respective cylinders.

Abstract: An improved top die raising and lowering guide mechanism for punching, pressing, and shearing machines having three hydraulic cylinder sets installed in a triangular configuration and, furthermore, three piston rod sets conjoined to an attachment mount to which is mounted a top die that is thereby guided during ascent and descent to execute punching, pressing, and shearing operations. The innovation of the present invention is that the top and bottom ends of the triangularly arranged three hydraulic cylinder sets are interconnected such that when a hydraulic system conveys hydraulic fluid to and from the top and bottom ends, the piston rods are simultaneously raised or lowered.