Abstract: A method for barring a rotor of a thermally loaded turbomachine includes stopping normal operation of the turbomachine; providing a barring device for rotating the rotor about a machine axis; coupling the barring device to the rotor; letting the rotor cool down during cool down of the rotor rotating the rotor by means of the barring device. A damage of the machine due to thermally induced buckling during the barring process is avoided by consecutively determining the force or torque applied to the rotor by the barring device for rotating the rotor and/or the circumferential speed of the rotor during barring. The rotation of the rotor is controlled by means of the barring device in dependence of the determined force or torque and/or circumferential speed in order to reduce a bending or imbalance of the rotor, which is due to a nonuniform temperature distribution on the rotor during cool down.

Abstract: A device for positioning the rotor of a gas turbine by linearly actuating a piston rod that actuates on its end a ratched wheel that moves the rotor of the gas turbine. The device includes an eccentric wheel and a synchronous motor. The piston rod is moved through the eccentric wheel, which is connected to the synchronous motor. The device also includes an incremental counter controlling the angular position of the synchronous motor. The device can permit accurate positioning of the rotor for boroscopic inspection.

Abstract: A multiple-stage fluid operated actuator (100) is provided. The multiple-stage fluid operated actuator (100) comprises a housing (101) including a first bore (212) with a first cross-sectional area and a second bore (215) with a second cross-sectional area. The multiple-stage fluid operated actuator (100) further comprises a piston assembly (210) including a first piston (210a) movable within the first bore (212) and a second piston (210b) movable within the first and second bores (212, 215). The piston assembly (210) separates the first and second bores (212, 215) into a first fluid chamber (214a) selectively in fluid communication with a pressurized fluid source (220) or an exhaust, an airtight second fluid chamber (214b), and a third fluid chamber (214c) selectively in fluid communication with the pressurized fluid source (220) or the exhaust.

Abstract: A multiple-stage fluid operated actuator (100) is provided. The multiple-stage fluid operated actuator (100) comprises a housing (101) including a first bore (212) with a first cross-sectional area and a second bore (215) with a second cross-sectional area. The multiple-stage fluid operated actuator (100) further comprises a piston assembly (210) including a first piston (210a) movable within the first bore (212) and a second piston (210b) movable within the first and second bores (212, 215). The piston assembly (210) separates the first and second bores (212, 215) into a first fluid chamber (214a) selectively in fluid communication with a pressurized fluid source (220) or an exhaust, an airtight second fluid chamber (214b), and a third fluid chamber (214c) selectively in fluid communication with the pressurized fluid source (220) or the exhaust.

Abstract: We present a high-efficiency crankless reciprocating steam engine that loses only a small amount of energy when the rectilinear motion of its piston is changed into the rotary motion of its driveshaft. The present invention continuously rotates a valve in one direction while alternately introducing steam into two piston housing chambers to generate the rotary force of the driveshaft. Therefore, engine efficiency is greatly increased because the inertial force losses in the valve are much smaller compared to the case when the valve rotation stops or changes direction.

Abstract: A fluid control system is disclosed that includes a first double-acting actuator and a second double-acting actuator. A first independent metering valve has a first control port connected to the first double-acting actuator, a second control port connected to the second double-acting actuator, first and second independently operable valves disposed between the inlet port and the first and second control ports, and a first check control mechanism having a main check valve between the inlet port and the first and second independently operable valves. The first check control mechanism controls the main check valve to allow the first and second actuators to operate in either an independent function mode or a regenerative function mode.

Abstract: A wood splitting apparatus has a parting blade and a platen which undergo reciprocating motions in mutually opposite directions by means of a pair of hydraulic cylinders. After the parting blade splits off a portion of a sawn log horizontally, the portion which has been split off is dropped and then pushed by the platen into and through a cutting block provided with a plurality of knives so as to be cut into smaller pieces. The pair of hydraulic cylinders is directly connected by a pipe through which a hydraulic liquid can flow back and forth therebetween and is together controlled by a single valve for power economy. The floor of the cutting block is of an inverted V-shape and the knives are oriented such that the intervals therebetween increase on the downstream side so as to prevent jamming of the apparatus by the wood pieces.

Abstract: A manifold (2) is provided with a first passage (4) for supplying pressurized oil and a second passage (5) for air venting. The manifold (2) has a support surface (9) to which a housing (12) of every hydraulic cylinder (7) is hermetically fixed through a sealing member (10). A piston (14) is inserted into a cylinder bore (13) of the housing (12). A hydraulic chamber (15) is formed between the piston (14) and the support surface (9). The hydraulic chamber (15) directly opposes to the support surface (9). The first passage (4) communicates with the respective hydraulic chambers (15) through branched passages (17). The hydraulic chamber (15) has an upper portion communicated with the second passage (5) through an air vent passage (18).

Abstract: An improved spring brake actuator includes an improved valve housing which incorporates pressure test points into the air supply, and further incorporates an anti-compounding valve. By incorporating the anti-compounding valve and test points directly into the valve manifold, the inventive spring brake actuator reduces the number of separate parts. The anti-compounding valve is operable to insure that there will be no compounding of the braking force.

Abstract: A switching valve has a control rod with a pilot chamber at each of its ends. For each pilot chamber, there is a first passageway connected to a pressure line and communicating with the pilot chamber. A second passageway is connectable to return. A relief valve has a valve member biased to close an orifice to close communication between the pilot chamber and the second passageway. The valve member has an open position in which the pilot chamber is connected to return via the second passageway to allow shifting of the control rod. In a first embodiment, the pilot chamber is continuously in communication with pressure via the first passageway, and the valve member is opened by this pressure in response to connection of the second passageway to return. In another embodiment, the second passageway is continuously in communication with return, and the valve member is mechanically moved into its open position by an operator in response to pressure acting on the operator.

Abstract: A hydraulic valve assembly configured for controlling the elevation and operation of a mowing deck of a power mower. The valve assembly includes a housing having a valve spool positionable in four positions, a cylinder activation position, a neutral position, a cylinder relief and motor start position, and a motor run position. In the cylinder activation position pump pressure is connected to a deck raising cylinder. In the neutral position, a status quo is maintained, and pump is vented to tank. In the cylinder relief and motor start position, the mowing deck, if elevated, is lowered under its own weight by relieving pressure on the deck cylinder, and the mowing motor is started in operation under low pressure. In the motor run position, the motor is connected to high pressure, and the deck cylinder continues to be vented to tank.

Abstract: The piston rods (10, 12, 14) of three linear hydraulic motors (M1, M2, M3) are stationary and include fluid pressure passageways (40, 52, 42, 54, 44, 56) which direct fluid pressure into and out from working chambers (16, 34, 18, 36, 20, 38) on opposite sides of piston heads (22, 24, 26). Movable cylinder barrels (16, 18, 20) are connected to a load, e.g. floor members (FM1, FM2, FM3) of a reciprocating floor conveyor (FIG. 18 ). The outer ends of the piston rods (10, 12, 14) include balls and the balls include ports (46, 58, 48, 60, 50, 62) through which fluid pressure is delivered or removed. Associated with each port is a limit valve LV1, LV2, LV3, LV4, LV5, LV6. Limit valves (LV1, LV2, LV3) are pushed into an open position by a retraction of the motors (M1, M2, M3). Limit valves (LV4, LV5, LV6) are pulled into an open position by extension of motors (M1, M2, M3). The limit valves (LV1, LV2, LV3, LV4, LV5, LV6) include springs biasing them into closed positions.

Abstract: Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). Three transverse drive beams (48, 50, 52) are provided. Each drive beam (48, 50, 52) is directly connected to an associated one of the cylinder housings (72). Three sets of floor slat members (1, 2, 3) are provided. Each set (1, 2, 3) is connected to an associated one of the transverse drive beams (48, 50, 52). The linear hydraulic motors (36, 38, 40) are operated for moving the floor slat members (1, 2, 3) in one direction, for advancing a load, and for retracting them in the opposite direction. Each cylinder housing (72) has four fluid chambers (82, 84, 86, 88). The first and third chambers (82, 86) are interconnected and the second and fourth chambers (84, 88) are interconnected.

Abstract: Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). Three transverse drive beams (48, 50, 52) are provided. Each drive beam (48, 50, 52) is directly connected to an associated one of the cylinder housings (72). Three sets of floor slat members (1, 2, 3) are provided. Each set (1, 2, 3) is connected to an associated one of the transverse drive beams (48, 50, 52). The linear hydraulic motors (36, 38, 40) are operated for moving the floor slat members (1, 2, 3) in one direction, for advancing a load, and for retracting them in the opposite direction. Each cylinder housing (72) has four fluid chambers (82, 84, 86, 88). The first and third chambers (82, 86) are interconnected and the second and fourth chambers (84, 88) are interconnected.

Abstract: A manipulator for engaging a pouring tube (11) with a discharge gate of a pouring ladle comprises a post (3) and a boom (4), which is adjustably mounted on the post (3) and adapted to carry the pouring tube (11). To provide for a simple sequence of movements and a simple control, the post (3) is pivoted to a base (1) on a horizontal axis (2), the boom (4) is pivoted to the post (3) on an axis (5), which is parallel to the pivotal axis of the post (3), and the post (3) and the boom (4) are pivotally movable about their respective pivotal axes by respective torque cylinders (6).

Abstract: A driving apparatus for producing a to-and-fro movement and having four plunger cylinders and four external non-return valves. Such driving apparatus is distinguished by a particularly simple construction.

Abstract: A fluid flow control apparatus having an adjustable throttling arrangement for controlling the flow of fluid between working cylinders associated with sections of an articulated vehicle, has a housing which is essentially symmetric in shape. Two working connections are formed at symmetrically opposite ends of the housing and connect to the working cylinders. Two passageways, formed in the housing to connect the two working connections, are also symmetrically formed and are approximately equivalent in length. The first passageway uses a check valve arrangement to restrict fluid flow from the first working connection to the second working connection while the second passageway uses a similar check valve arrangement to restrict fluid flow in the opposite direction. The two passageways interconnect at a crossover duct which acts as a guide for the throttling arrangement.

Abstract: A hydraulic steering system for use in four-wheel running vehicles or the like of small size and low horsepower. The steering system and a hydraulic system for lifting a working implement are both operable by a single hydraulic pump without the necessity of using a variable displacement hydraulic pump or providing two hydraulic pumps for the two systems. The steering system is operable by an engine of low horsepower.

Abstract: A fluid-pressure driving device including a main actuator unit having a piston adapted to travel a full part of a predetermined stroke and an accelerating actuator unit having a piston adapted to travel only a part of the stroke and being capable of operating only during the acceleration of the object to be actuated. These actuator units are operated under the control of a control valve such that, in the accelerating range in which the speed of the object is still low, both actuator units operate to produce a large actuating force, while, after the acceleration, only the main actuator unit operates to fully travel the required stroke.

Abstract: An actuator output member (11) is angularly deflectable by two opposed, tangentially movable, pressure transmitting members (7, 8), each responsive to the pressure drop developed across two respective flow restrictors (1, 2) serially connected in a fluid circuit. Deflection is achieved by variation of one or both of the flow restrictors. In a fast response arrangement the fluid is electroviscous and the flow restrictors electrically variable.

Abstract: A piston-cylinder assembly for displacing a load through a long stroke consists of a rod, a piston slidable on the rod and by fluid pressure the piston is clamped to the rod, and a cylinder in which the piston is contained. By clamping the piston to the rod and introducing fluid into the cylinder, relative movement is caused between the piston and cylinder and the rod. When one assembly is used, the movement is intermittent but, by mounting two pistons on the rod, each piston being in a separate cylinder, and by controlling the flow of fluid, the movement is continuous.

Abstract: The invention relates to an oil well jack having a walking beam mounted on a frame for motion in a vertical plane; and a plurality of hydraulic actuators connected to move the walking beam. The amplitude of movement of the beam as well as the frequency of the stroke are adjustable through regulation and control of the hydraulic system.

Abstract: An improved hydraulic swing mechanism is disclosed for operation of the boom assembly of a backhoe or similar implement. The swing mechanism includes a pair of double-acting hydraulic motors pivotally interconnected between the backhoe frame and the backhoe boom assembly. A novel multi-position sequencing spool valve is disposed in fluid communication between the head ends of the hydraulic motors and a manually operated directional control valve which directs swinging movement of the boom assembly. A straight-forward valve control linkage operatively connects the sequencing spool valve with the boom assembly so that the spool valve is selectively operated as the boom assembly is pivoted through its arc of travel. An improved hydraulic cushioning circuit is provided in association with the sequencing spool valve, with the entire system providing improved operation of the boom assembly, with significant improvement in the hydraulic cushioning and torque characteristics of the system.

Abstract: A hydraulically operated pump jack utilizing dual hydraulically operated piston and cylinder assemblies for pivoting the beam of the pump jack and including a unique control arrangement associated with a reversing valve for controlling operation of the piston and cylinder assemblies. The control arrangement includes a hydraulically operated holding valve incorporated into each of the conduits between the reversing valve and the hydraulically operated piston and cylinder assemblies combined with a control piston and cylinder assembly for controlling the operation of the holding valves. A manually operated valve assembly is also incorporated into each conduit to enable conversion of either or both of the piston and cylinder assemblies from double acting to single acting.

Abstract: A three position fluid actuated device including a cylinder, end walls, a central wall dividing the cylinder into two chambers and a stop midway in one chamber. A piston is slidable in the other chamber and is attached to one end of an output shaft which extends beyond the opposite end wall. Two floating pistons are slidable on the shaft in the one chamber on opposite sides of the stop. A snap ring on the shaft displaces the floating pistons toward the central and end walls. Four ports in the end and central walls permit moving the shaft to three positive positions.

Abstract: A contact free device for limiting the relative movement of hydraulically actuated members in which the device includes a proximity switch actuated at each limit position of the members and which interrupts the supply of hydraulic actuating fluid to the members. The supply of fluid to the members is resumed when movement of the members relatively away from the respective limit position is initiated.

Abstract: The arm of a forging manipulator has tongues at one end for engaging with a workpiece and is journaled for rotation about a horizontal axis. At the other end the arm carries a pair of clamps each of which has a pair of clamping jaws pivotally connected at one end and adapted to be spread apart or drawn against the arm by a spreading hydraulic cylinder at the other end of each pair of jaws. The cylinders are interconnected for reversing operation and are hydraulically linked to a pair of drive cylinders, the pistons of which are pivotally connected to the respective clamps so that one of the drive cylinders is effective to rotate the arm when its clamping cylinder draws its jaws against the arm while the other clamping cylinder spreads the other pair of jaws apart during the ineffective stroke of the drive piston.

Abstract: Mounted between a frame and a dozer blade at opposite sides of vertically spaced stabilizing and ball joint connections joining the frame and blade are a pair of hydraulic angling actuators which are operative to angle the blade about a vertical axis defined by the connections. A hydraulic tilt actuator is connected between the frame and blade in the vicinity of the stabilizing connection and is operative to tilt the blade about a fore-and-aft axis passing through the ball joint connection. Pressure relief circuitry including a normally closed relief valve is connected to the angling actuator and the relief valve is opened in response to a predetermined pressure build-up in the angling actuators, as occasioned by changes in the location of the points of connection of the angling actuators with the blade during tilting of the latter, to exhaust fluid from the angling actuators to permit extension or retraction thereof.

Abstract: A hauling device, for example for a mining machine, has two clamping elements which grip on ramps each of which elements is attached to an operating rod of a hauling jack. The jacks are operated alternately, in conjunction with the clamping elements to advance or retract the machine, and the hauling jacks are hydraulically interconnected in a manner to avoid hunting.

Abstract: A hydraulic swivel drive with two adjusting cylinder-piston systems the connecting rods of which are pivotally connected to a pivotally mounted member to be actuated by the hydraulic swivel drive. The cylinder-piston units are mounted on a base member, e.g. a base plate, which base member is provided with a servo-valve controlling the supply of actuating fluid to the cylinder-piston units which are arranged in V-formation and are hooked up with the pivotally mounted member so as to be symmetrically arranged with regard to the pivot axis of the pivotally mounted member. The cylinder-piston units are directly connected to the base member and their connecting rods are pivotable relative to the axis of their pertaining cylinder.

Abstract: An adaptive actuator system comprising a rotatable shaft operatively coupled to a torque biasing means for biasing the rotational direction of the shaft, and also operatively coupled to a counter torque developing means for sensing the rotational bias of the shaft and providing a counter torque proportional to the rotational bias.