Abstract: An apparatus has a mass suspended between two mounting plates by a separate springs to form a resonant structure that absorbs vibration in a structural member to which the mounting plates are attached. Permanent magnets are fixed to opposite sides of the mass. A sensor produces a signal indicating the frequency of the vibration. A feedback circuit receives the signal from the sensor and produces an output signal having first component frequency which corresponds to a harmonic of the frequency of the vibration. The output signal is applied to a separate voice coil adjacent to each permanent magnet. The magnetic fields produced by the output signal flowing through the voice coils interact with the magnetic fields from the permanent magnets to generate forces that act on the mass in a manner that increases the impedance of the absorber to the vibration in the structural member.

Abstract: An interior arrangement used in an expandable room structure includes a first room section having a stationary floor with an upper surface. A second room section is movable relative to the first section between a retracted position and an extended position to expand the interior volume of the vehicle, and the second room section has a floor with a top surface. A pair of substantially parallel outer rails is provided for supporting the first room section, and a pair of substantially parallel inner rails is provided for supporting the second room section. Each of the inner rails is slidably mounted for longitudinal movement relative to one of the outer rails. An operating mechanism selectively moves the inner rails relative to the outer rails to extend and retract the second room section relative to the first room section.

Abstract: A bidirectional on/off spool valve has circumferentially-extending through-slots in a spool which are axially alignable with circumferentially-extending grooves in the main bore. The slots and grooves create a flow path through the valve which minimizes Bernoulli forces that tend to close the valve or create negative Bernoulli forces which help keep the valve open. The spool has a stop wall at its closed end which restricts the open area of the lumen of the spool and a balance tube extends forwardly from the stop wall to equalize the pressure behind the stop wall with the pressure in front of the stop wall, so that the spool is not locked in the open position.

Abstract: A distribution duct for power distribution wiring, data communication wiring, and the other wiring is mounted between adjacent perforated support columns of a work space system. The duct extends laterally from the columns to allow the wiring to pass the face of a column. The duct includes an inner elongated member which rests at each end in a perforation in a respective column. A resilient clip holds each end of the inner member in the perforations. The inner member has an open side that is covered by an elongated outer member that is coextensive with the inner member and extends laterally away from one side of the columns. The outer member is snapped in place on the inner member, and covers snap in place on the outer members to connect the ends of adjacent outer members. An identical inner member may be mounted to the rear of a first inner member and receive a similar outer member to form a two-sided duct.

Abstract: A non-contact voltage tester has a self-test feature so that when a switch clip of the tester is actuated, light and sound indicator devices are energized to give a single blink and beep, respectively, following which the tester is ready for probing for a voltage. The light and sound indicator devices also indicate the presence of a voltage when the switch is actuated and a voltage is detected at the probe tip of the tester.

Abstract: An aircraft engine is attached to the fuselage by a mounting structure that has a vibration absorbing system which includes first and second sensors to produce signals indicating vibration along two orthogonal axes. A third sensor, such as an accelerometer, is coupled to the mounting structure for sensing vibration of the engine. A tachometer circuit, connected to the third sensor, produces first and second speed signals that indicate the speeds of two rotating spools in the engine. Four vibration absorbers are attached to the engine mounting structure and controllers are provided to dynamically tune the resonant frequency of each vibration absorber in response to a unique combination of one of the two vibration signals and one of the two speed signals. Thus the vibration absorbers reduce the engine spool vibrations that are transmitted through the mounting structure along the two orthogonal axes.

Abstract: Hydraulic operating device, in particular for the operation of a selector fork of a gearbox, and gearbox provided with such an operating device. The device comprises a double-acting cylinder, which is coupled to the selector fork, and a reversible pump. The pump is connected to the working chambers of the cylinder by supply lines. A valve is mounted in each of the supply lines which is operated by fluid flow. This valve comprises a body, a bore formed in the body, a piston, which divides the bore into two chambers, a through-channel, formed in the piston and designed as a flow orifice, connecting the two chambers.

Abstract: An electrohydraulic tilting device for a vehicle with a tilting cab has a pump, an electric pump drive motor connected by way of an electrical connecting line to a source for electrical energy, and a hydraulic piston/cylinder unit connected to the pump. The piston/cylinder unit is designed for exerting a force which is capable of tilting the cab forward and back. An overcurrent protection device is provided which is designed for automatic interruption and subsequently maintaining the interruption of the electrical power line of the pump motor when the electrical power taken up by the pump motor for a predetermined period exceeds a first threshold value which is higher than the maximum electrical power required during normal tilting of the cab. The overcurrent protection device is provided with manual reset means for ending the interruption of the power line.

Abstract: A hydraulic circuit for controlling a plurality of hydraulic motors of a machine has a reversible pump with its suction/pressure ports connected to the inputs of an OR-valve is connected to the input of at least one 3/2 electro-valve, which has its output connected to the inputs of the AND-valves which are not connected to the pump. The AND-valve outputs and the suction/pressure ports are used individually or in combination to control the hydraulic motors.

Abstract: A fish tape locator has a first threaded end for fixing to the end of a fish tape and an opposite second end which emits light to help locate the end of the fish tape when it is being fished through a blind space. The first end is provided with a cross-bore for connecting the locator to a string, chain, hook or other line.

Abstract: A hydraulic control valve has a two position body shifted by rotation. The shaft of the valve body carries a drive wheel segment extending through an arc that corresponds to the shift angle of the valve. A spring is provided to bias, at least in the final stage of rotation in either direction, the wheel segment in the opposite direction of rotation. This enables the valve body to be positioned into the other position in a reliable manner.

Abstract: An apparatus for counteracting vibrations includes a housing for attachment to a vibrating member. First and second bodies are connected to the housing by first and second springs, respectively, with a combined stiffness which defines a resonant frequency at which the first and second bodies oscillate with respect to the housing. Each of the first and second springs include a plurality of rods fixedly connected between a pair of rings. A lever engages the first and second bodies to vary a spacing between those bodies when force from an actuator is applied to the lever. The lever action alters the stiffness of the first and second springs which varies the resonant frequency of the vibration absorber.

Abstract: A system for tightening a threaded fastener with a hydraulic wrench has a pumping unit which measures parameters representative of the torque applied to the fastener and the angle of advance of the fastener, remote from the wrench. The pump measures pressure as a parameter representative of torque and measures, pump speed as a parameter which is processed so as to be representative of the angle of advance of the fastener. A ratchet-type hydraulic wrench is used, and the pressure versus angle data produced in tightening a fastener is manipulated to discard irrelevant portions and smooth relevant portions to provide data representative of torque and angle during the tightening process from which to determine a final stopping parameter for terminating tightening. The system also has a calibration fixture for determining the volumetric rate of angle advance for a given wrench.

Abstract: A hydraulic pump assembly for powering a hydraulic torque wrench is air-powered and has hydro-pneumatic control circuitry which continues operation of an air motor which drives the hydraulic pump for a post-advance period after an advance actuator is deactuated. Operation of the pump is continued for a period sufficient to retract a double-acting torque wrench, to permit subsequent advances of the wrench within the post-advance period without restarting the pump or to permit a single acting wrench to be moved from one fastener to the next within the post-advance period without restarting the pump. Operation of the pump is terminated when the post-advance period expires if the advance actuator is not reactuated, so as to conserve energy and avoid unnecessary heating of the hydraulic fluid.

Abstract: Locking arrangement of a fluid insertion connection between a fluid line and a connection member, in particular between a hydraulic line and a hydraulic cylinder, the fluid line having an insertion part at one end and the connection member being provided with an insertion opening which is open at the circumferential surface of the connection member and receives the insertion part of the line. Furthermore, locking means are provided, which engage on an abutment surface of the insertion part of the fluid line in order to prevent the insertion part of the line from being pulled out of the insertion opening.The locking means comprise a ring, which is positioned around the connection member at the position of the insertion opening and is movable with respect to the connection member.

Abstract: Motor vehicle with a foldable roof, which foldable roof comprises a bow assembly with a main bow, a fabric tensioning bow which can be pivoted up and down, for the rear part of the foldable roof, and a buggy-link system with two links. These links at one side are pivotably connected to each other and are also pivotably connected to the fabric tensioning bow and to a fixing point of the bow assembly respectively.The foldable roof also comprises a power drive unit which is connected for drive purposes to the buggy-link system, and can move the buggy-link system between an extended position, in which the links thereof lie essentially in line with each other and thereby force the fabric tensioning bow downwards, and a bent position, in which the links lie at an angle relative to each other.The power drive unit, for example a hydraulic cylinder, is placed in a side wall part of the vehicle.