Showing papers on "Damping torque published in 1974"

Frequency selective damping circuits

Abstract: In A.C. power systems, large capacitors used in conjunction with synchronous or induction machines, or with saturable reactors, are prone to self-excited oscillation at harmonic or sub-harmonic frequencies. Damping circuits are known in which supply-frequency capacitor current is kept away from a damping resistance path by a series or shunt resonant circuit. The invention provides improved damping of harmonic or sub-harmonic oscillations by adding capacitance or inductance, or both, to achieve a resonance at the parasitic frequency and so force the parasitic current through the damping resistance.

Torque control system for reaction wheel assemblies and the like

Abstract: An improvement in torque control systems for reaction wheel assemblies and the like used primarily for stabilizing space vehicles such as satellites including means for integrating the torque command signal and combining the integrated torque command signal with a feedback signal proportional to the angular speed of the rotor of the reaction wheel assembly thereby producing an error signal proportional to the difference between the integrated torque command signal and the angular speed signal. The error signal is coupled to the rotor spin motor which produces a resultant output torque that has been compensated for disturbance torques and other anomalies whereby the resultant torque applied to the rotor and consequently to the satellite is substantially equal to the commanded torque.

Multiple range torque measuring tool

Abstract: A torque measuring tool in which the twist of a torsion bar indicates the magnitude of applied torque comprising: A. Means to utilize a variety of conventional wrenches of any desired length. B. Interchangeable torsion bars for various torque ranges utilizing one scale with interchangeable numerical displays appropriate to each torque range. C. Means to absorb excess torque, preventing accidental damage to the torsion bars and permitting unilateral readouts. D. Interchangeable readout modes with very simple means of zeroing.

Torque limiting converter stator

Abstract: A variable capacity torque converter in which the reactor vanes are pivoted in response to the torque absorption capacity of the impeller to limit the torque output of the turbine. The torque ratio, output torque divided by input torque, of the converter is reduced by controlling the angle of the reactor vanes such that, when the torque capacity of the impeller is at a high value, the torque ratio is lowered to limit the maximum torque that can be delivered by the turbine. The reactor vanes are pivotally mounted on an axially movable member such that fluid flow forces, proportional to impeller capacity, acting on the reactor vanes cause the vanes and the movable member to move axially resulting in pivoting of the vanes to change the torque ratio of the torque converter.

Magnetic damping force in electrodynamically suspended trains

Abstract: A magnetic levitation system utilizing superconducting magnets is now being developed for a high speed ground vehicle. From a view point of ride quality, a damping force for the mechanical oscillation of a levitated vehicle is one of the most important problems in this levitation system. This paper presents the analysis of the magnetic damping force in a loop track magnetic levitaion system; the magnetic damping force is caused by track loops. It is theoretically pointed out that the magnetic damping force is "negative" except in an extremely low velocity range. The theory is applied to the estimation of the magnetic damping force in a train model of practical interest. The results of the estimation suggest that the negative magnetic damping force is considerably large in a median velocity range (100 ∼ 200 km/h). Passive damping has been also investigated; it is found that damper loops installed in the levitation cryostat is effective even in persistent mode operation. It is concluded that rather good ride quality will be obtained by use of the passive damping method.

Mechanical automatic torque converter

Abstract: A torque converter that uses the reaction of energy storing devices to mechanically convert a given input angular velocity into an output torque. The torque converter is comprised of an input shaft which delivers an oscillatory motion to an inertia device, such as a flywheel, through connecting rods and lever arms. The inertia device transfers the oscillatory motion to the output shaft through differential gears and overrunning clutches. In the preferred embodiment, two inertia devices mounted on parallel axes with each 90° out of phase provide a smooth, continuous output torque.

Damping of aeolian vibration on overhead lines by vibration dampers

Abstract: A new method is presented for determining the effectiveness of dampers used to suppress aeolian vibration on overhead lines. The method is applied to a Stockbridge damper and a simple picture is presented of the way in which this damper works. A second type of vibration damper is also considered, to demonstrate the way in which the performance of different dampers can be evaluated and compared using the new method.

Engine torque monitoring system

Abstract: The engine horsepower is computed as a function of the engine fuel flow rate and the engine torque is derived by the division of the horsepower signal by a signal functionally related to the engine speed. The actual torque of the engine is compared to a torque set point and upon a given deviation from the set point, corrective signals are actuated to return the actual torque to its set point. Upon too great a deviation, an alarm is actuated and the engine is completely unloaded. When used with ambient uprated engines, a temperature signal representing engine capability is used to limit the torque set point to its maximum allowable setting. Upon loss of the signal representing engine capability, the allowable torque is reduced as though there were no up-rating of the engine. The fuel flow computer utilizes signals from the differential pressure of the fuel, the static pressure of the fuel and the temperature of the fuel to produce a signal indicative of the square root of the product of the two pressure parameters divided by a signal functionally related to the fuel temperature.

Torsional extrusion energy absorber or extrusion torque limiter

Abstract: This instrument can fulfil two purposes. It can be a torque limiter which transmits torque up to a limit set by design, without slip. At higher values of torque it behaves as an absorber of energy. It can be cyclic or unidirectional or impact in operation. It can be applied as an absorber of wind or earthquake forces, as a buffer or fender in a transport system, as a brake, or as a torque limiter in a shaft transmitting power. Its commonest form is an eccentric within a cylinder, the intervening space being filled with a material capable of spontaneous recovery and recrystallisation at the working temperature.

Torque converter with a controlled stator for limiting the torque ratio

Abstract: A torque converter in which a controller stator is utilized to limit the torque delivered by the converter. The stator is controlled by a friction brake which is designed to have a limited capacity. When the stator torque is higher than the design capacity, the stator will rotate in a direction opposite to the impeller to limit the maximum torque ratio of the converter. The stator is also controlled during coast to provide churn braking.

Vehicle torque sensing device

Abstract: The invention is a device for sensing torque differential developed by the driven wheel of a vehicle and an indicator to indicate relative degrees of the developed torque

Vibration reduction with Continuous Damping Inserts

Abstract: The case of uniform structural elements containing continuous damping inserts distributed between them is considered both analytically and experimentally with models representing machine spindles and cantilever bars. Continuous inserts are shown to be advantageous relative to the more conventional discrete ones.

Torque sensor with means for mechanical damping

Abstract: The present invention teaches the use of a selectably exchangeable load cell which is activated by the downward thrust of a plunger transversely attached to the center or idler gear of a three-gear rotating train. The downward thrust is a direct linear function of the load which is applied to the driven gear. Further, a mechanical damping means is utilized in order to eliminate gear and bearing noise in the electrical signal. The use of mechanical damping, as opposed to an electronic filter, preserves a fast response time to changes in torque upon the driven gear.

Power tool torque indicating device

Abstract: A pneumatic power tool drive mechanism having coaxial drive and driven rotors and an intermediate torsion spring and relatively rotatable in accordance with the transmitted torque. A torque indicating device of the power tool comprises an axially reciprocable and non-rotatable torque scale operator actuated in one axial direction in accordance with the relative angular displacement of the drive and driven rotors to indicate the applied torque and urged in the opposite axial direction to reset the torque scale operator through the engagement of dimples on the torque scale operator with a helical cam on the driven rotor.