Showing papers on "Rotational speed published in 1976"

Computer program for design analysis of radial-inflow turbines

Abstract: A computer program written in FORTRAN that may be used for the design analysis of radial-inflow turbines was documented. The following information is included: loss model (estimation of losses), the analysis equations, a description of the input and output data, the FORTRAN program listing and list of variables, and sample cases. The input design requirements include the power, mass flow rate, inlet temperature and pressure, and rotational speed. The program output data includes various diameters, efficiencies, temperatures, pressures, velocities, and flow angles for the appropriate calculation stations. The design variables include the stator-exit angle, rotor radius ratios, and rotor-exit tangential velocity distribution. The losses are determined by an internal loss model.

Vertical axis wind turbines

Abstract: A vertical axis wind turbine comprises one or more aerofoil section blades attached to a support structure. The blade has at least one part thereof which is acted on by centrifugal forces as the blade rotates with the support structure and thereby caused to increase its angle of inclination to the said vertical axis when the speed of rotation increases beyond the normal operating range, whereby the rate of increase of rotational speed with wind speed is reduced.

Apparatus for windmill starts in gas turbine engines

Abstract: A torque converter is interconnected between the fan and core rotor of a turbofan engine such that the speed of the core rotor can be boosted from windmill speed to a speed sufficient to allow an in-flight start by selectively extracting power from the windmilling fan during the start sequence of the engine. Control logic is included to automatically drain the oil from, and thereby unload, the torque converter whenever the engine is in the operating speed region. Further assurance is provided by an overrunning clutch which decouples the system when the core rotational speed exceeds the converter output.

Rotational field sensor

Abstract: A rotational field, such as is produced by the rotation of a motor vehicle alternator rotor, has placed therein a conductor coil which is cut by the lines of force, or flux lines, of the rotating field. The coil is wound upon a magnetic strip which in turn is wrapped around the housing of the alternator. The rotational speed of the alternator rotor will cause corresponding pulses in the coil which are received by a circuit which utilizes the pulse rate to control an output.

High speed grinding spindle

Abstract: An apparatus for feed grinding workpieces comprises a workpiece spindle assembly for supporting a workpiece and a grinding wheel spindle assembly for supporting a grinding wheel, the two spindle assemblies being movable relative to each other to enable movement of the workpiece into pressure contact with the grinding wheel. A variable speed drive system rotationally drives the grinding wheel relative to the workpiece at a first predetermined speed of rotation different than the resonant frequency of the grinding wheel spindle assembly to effect feed grinding of the workpiece. Completion of the feed grinding or spark-out is detected after which the rotational speed of the grinding wheel is lowered to a second predetermined speed different than the resonant frequency of the grinding wheel spindle assembly when operating in the spark-out mode. The high speed rotation during feed grinding assures good grinding quality and the low speed rotation during spark-out assures good surface finishing. By rotating the grinding wheel spindle assembly at speeds other than its resonant frequencies, damage due to large vibrations of the assembly is avoided.

Process and universal downhole motor for driving a tool

Abstract: The process enables, while starting from the same basical members, assembled in two different arrangements, to drive an earth-boring tool such as a bit, a milling cutter, a core barrel or the like with a reduced speed or a fast speed, according to the prevailing boring conditions. The downhole motor comprises a shaft and a body constituted by two helicoidal gears arranged within each other, providing an encapsulation preferably of right-handed pitch and having K and K+1 teeth. For providing a reduced speed the body is rotatably mounted and the tool is connected to said body. The shaft is angularly fixed and free to undergo a nutation movement. The resulting speed is the relative speed of rotation between the said body and the said shaft. For providing a fast rotation speed, the body is angularly and radially fixed. The helicoidal shaft meshes with the body and is supported in order freely to rotate around a crank system. The tool is connected to the crank.

Rotational viscometer and plastometer

Abstract: Concentric cylinder viscometer comprising means for rotating an outer sleeve which exerts a viscous drag on an inner cylinder, the torque of which is registered by spring means, and in which the outer sleeve is rotated at any of several pre-selected speeds by a direct current motor, the speed of which is controlled by a phase-locked feedback circuit in which the instantaneous speed of the motor is detected by an incremental encoder, the signal from which is fed to a digital display showing the rotational speed and is also fed back to the phase-locked comparator circuit which causes the application to the motor of the voltage required to drive it at the desired speed. The circuit includes an oscillator and frequency dividers which provide a plurality of precisely controlled frequencies, and also includes a variable oscillator which provides any desired hand-settable frequency over a wide range. The device is particularly adapted to the testing of drilling fluids.

Electro-optical speed transducer

Abstract: A speed transducer for measuring the speed of a moving surface comprises a light chopper for alternately completing and breaking the respective light paths between a light source and first and second photodetectors such that the second light path is completed before the first light path is broken. A pulse generator produces a pulse having a duration which is determined by the time interval between completion of the first and second light paths. A converter converts the pulse to a direct current signal proportional to the speed of the moving surface by generating a comparison pulse, the width of which is controllable by a direct current control signal, and comparing the widths of the generator and comparison pulses to produce an error signal which is indicative of the difference in widths. A control signal is generated in response to the error signal which constitutes the desired output when the compared pulse widths are equal. In a second embodiment, the sum of two pulses representing the speed of a rotating surface at two opposed locations is integrated to produce a direct current signal proportional to the concentric rotational speed only.

Variable speed transmission

Abstract: A gyroscopic type, infinitely variable, fully automatic, mechanical power transmission, speed changer, or torque converter capable of transmitting a wide range of output torques and automatically performing at the most appropriate input-to-output rotational speed ratio for the most efficient transmission of power in any given situation. In its most basic design, it comprises a rotatable main frame, two identical and separate sub-frame members which are rotatably mounted within the main frame, four identical gyroscopic-type rotors which are coaxially spin-mounted in pairs within the sub-frames, and two stators, one for each sub-frame, with each stator circumferentially positioned around the sub-frame member. Operationally, the rotors have radii of gyrations which are varied automatically in predetermined sequence in concert with the rotation of their sub-frame members. When the rotors are spinning and a precessional torque is applied from an input power source such as to impart contra-rotation to the sub-frames, the paired rotors will generate an effective output torque to the output shaft via the main frame.

Variable displacement piston engine

Abstract: A variable stroke piston engine in which power developed by piston reciprocation is transmitted to a cylindrical nutating member journaled on its exterior to a rotatable support connected to a second shaft concentric with the first shaft, the nutating member having an internal surface in frictional engagement with a pair of oppositely convergent cone-like members keyed for rotation with the first shaft. The nutating member is disposed on an axis inclined with respect to the axis of the first shaft at an angle which may be adjusted to vary simultaneously piston stroke distance and rotational speed of the first shaft without changing the rotational speed of the second shaft for a given frequency of piston reciprocation. The first and second shafts are connected respectively to each of two inputs of an epicyclic gear train having an output planet gear carrier connected to an engine output shaft. The geometry of the engine enables operation by which output shaft speed varies inversely with piston stroke length or engine displacement.

Method of and apparatus for feeding nonround-section bars to screw machines

Abstract: A screw machine has a headstock provided with an openable and closable chuck rotatable at high speed and having a throughgoing aperture of cross-sectional shape complementary to that of a bar to be machined in the screw machine. A feed apparatus for this machine comprises means for detecting the rotational speed of the chuck and for generating a speed output when the rotational speed lies within a predetermined range. In addition, a pusher is provided which only advances the bar into the aperture of the chuck after generation of the output. This pusher is engageable with an abutment that is only displaced out of its way when the speed output is generated. Furthermore the apparatus generates a position output when the bar is properly in place and has a timer which withdraws the bar from the chuck if within a predetermined time limit after generation of the speed output the position output is not generated, indicating that the apparatus is unable to load the bar.

Rolling method of sorting particulate articles

Abstract: High speed feeding, counting, orienting and storing of small parts such as ammunition, candy, pills, machine screws, nuts, miniature containers and the like. The articles are radially distributed upon a rotating planar surface having an axis; the articles are then advanced upon a plurality of peripherally spaced spindles or rollers which extend radially outwardly from the axis. The articles are then discharged from the spindles. The spindles may be of the idler or power driven type enabling the sorting of heavy parts. For example, the spindles may be rotated at a speed proportional to the rotational speed of the inner axis, such that the high surface speed of the individual rollers will enhance discharge, alternatively, the rollers may be rotated at a speed lower than the rotational speed of the inner axis which will enhance radial distribution prior to discharge.

Manufacture of metal strip

Abstract: Metal strip is peeled from the periphery of a rotating cylindrical workpiece by feeding a cutting tool continuously into the workpiece periphery and is collected by winding the peeled strip around a rotating coiler. The rotational speed of either the workpiece or the coiler is controlled to maintain its peripheral speed substantially constant at the angular velocity of, respectively, the coiler or the workpiece is controlled in accordance with a time-dependent derived relationship to maintain a set ratio between the peripheral speeds of the workpiece and the coiler.

Advanced radial inflow turbine rotor program: Design and dynamic testing

Abstract: The advancement of small, cooled, radial inflow turbine technology in the area of operation at higher turbine inlet temperature is discussed. The first step was accomplished by designing, fabricating, and subjecting to limited mechanical testing an advanced gas generator rotating assembly comprising a radial inflow turbine and two-stage centrifugal compressor. The radial inflow turbine and second-stage compressor were designed as an integrally machined monorotor with turbine cooling taking place basically by conduction to the compressor. Design turbine inlet rotor gas temperature, rotational speed, and overall gas generator compressor pressure ratio were 1422 K (2560 R), 71,222 rpm, and 10/1 respectively. Mechanical testing on a fabricated rotating assembly and bearing system covered 1,000 cold start/stop cycles and three spins to 120 percent design speed (85,466 rpm).

Brake operated low ratio release

Abstract: A drive arrangement for motor vehicles equipped with a mechanism for raising the idling rotational speed of the driving engine during its warm-up phase and with an automatic transmission whose lowest speed is adapted to be engaged by at least one servo-device; the servo-device is thereby adapted to be automatically disengaged upon actuation of the vehicle brake in the lowest speed which is coordinated to the selected drive range.

Automatic switch system to temporally stop IC engine - engine is started by clutch pedal dependent switch and stopped by slow running valve

Abstract: Vehicle has an electronic regulator receiving signals from a clutch pedal-actuated transmitter and signals proportional to the vehicle road speed from an electrical tachometer. A third input is from the vehicle battery and a final input comes from the ignition contact breaker to give an engine rotation speed representative signal. A manual switch on the instrument panel is connected to the carburettor slow running valve to overide the electronic regulator. Two outputs from the regulator lead respectively to the starter motor solenoid and the slow running valve. The regulator contains a resistance circuit which is charged by a running engine and discharged by a stationary engine, as well as a NAND gate which only passes a start signal when the resistance capacity circuit is charged. The engine is switched off after a two second delay when the engine revolutions speed falls below a predetermined value (300 revolutions per minute).

Hydrodynamic torque converter for vehicles, especially for motor vehicles

Abstract: A hydrodynamic torque converter for vehicles, particularly for passenger motor vehicles, with at least one pump wheel, one turbine wheel and one guide wheel supported on a free-wheeling device, in which the guide blades are automatically adjustable, when the guide wheel rotates, in dependence on the centrifugal force in the sense of a cascade opening with an increasing rotational speed.

Method and apparatus for controlling the wheel brakes to prevent skid

Abstract: A brake control system for vehicles in which the difference in speed of rotation of a corresponding pair of wheels is detected in a prebraking mode of operation. If the difference in rotational speed exceeds a predetermined amount, the brakes on the pair of wheels are disabled. In one embodiment of the invention, the prebraking rotational speed ratio of the pair of wheels is determined by a comparator and electronic voltage control circuit, and the electrical output thereof fed to a valve control circuit for controlling the brake valves to maintain the braking rotational speed ratio of the wheels substantially equal to the prebraking rotational speed ratio. In the event the control circuits are unable to maintain the braking rotational speed ratio substantially equal to the prebraking rotational speed ratio, and such ratio exceeds a predetermined value, and a pendulum switch mechanism combined therewith indicates the beginning of a vehicle skid and spin, the brakes will be automatically disabled on both wheels. The disablement of the brakes is caused by a pair of pendulum switch mechanisms in combination with the control circuit.

Reel-to-reel drive with speed control

Abstract: Long and short term variations in the speed at which a magnetic tape is moved with respect to a read and/or write head are minimized by maintaining the product of the speed of the tape payout and take-up reels constant. In accordance with a preferred embodiment the rotational speed of the payout reel and the rotational speed of the take-up reel are sensed and effectively multiplied to derive a signal which is compared with a predetermined constant magnitude reference signal. The result of the comparison is an error voltage which is employed to energize and thus control the speed of the drive motor for the take-up reel.

Speed and phase control system

Abstract: In an apparatus having at least one rotary head for reproducing video signals recorded in successive parallel tracks extending obliquely across a tape which is advanced longitudinally and also has control signals recorded therein in predetermined positional relationship to the respective record tracks to be reproduced by a fixed transducer or head with a repetition rate that is dependent on the speed of advancement of the tape: a speed and phase control system for the rotary head or heads has a rotational speed detector for producing pulse signals representative of the rotational position of each rotary head and having a repetition rate that is a function of the rotational speed of the rotary head; a phase comparator for producing a phase responsive signal having a voltage level that is varied in response to changes in the relative timing of the reproduced control signals and the pulse signals; a digital device for producing a speed responsive signal having a voltage level that generally corresponds to the repetition rate of the pulse signals, but which is varied in response to changes in the repetition rate of the pulse signals only when such changes occur without corresponding changes in the repetition rate of the reproduced control signals; and a brake or other means for controlling the rotation of the rotary head in response to the voltage levels of the phase responsive signal and the speed responsive signal. In a preferred embodiment, the digital device for producing the speed responsive signal includes a source of clock pulses, a counter for counting the clock pulses for time intervals determined by the repetition rate of the pulse signals from the rotational speed detector, a digital-analog converter for converting the count of the counter, at the end of the mentioned time intervals, to a corresponding voltage level of the speed responsive signal, and an arrangement for establishing the initial count of the counter at the commencement of each of the time intervals in dependence on the repetition rate of the reproduced control signals.

Rotational rate of change sensor

Abstract: A sensor responsive to the rate of change of changing rotational speeds of a rotatable element in which a flyweight is yieldably coupled with the rotatable element through an interconnecting element at any relative rotational position of the flyweight and interconnection for normal rotation thereof at a known ratio of rotational speed while accommodating decoupled rotation of the flyweight upon a change in rotational speed of the driving element at such a rate as to cause a torque in excess of a determinable threshold torque to act between the interconnection and the flyweight. During decoupled rotation, the flyweight is limited to deceleration at a controlled, substantially constant rate. Any occurrence of decoupled rotation of the flyweight is signalled as indicating that the rate of change of the changing rotational speed of the rotatable element exceeds a determinable rate. In the particular instance of an automotive vehicle wheel, the signalled occurrence indicates wheel slip and sensor signals may be used with an appropriate brake modulator for varying braking force.

Circuit for limiting the spindle speed of a machine

Abstract: An apparatus for insuring that the rotational speed of a spindle on a machine is prevented from exceeding a selected programmed speed. The apparatus is comprised of means for continuously receiving pulsed signals indicative of the instantaneous rotational speed of the spindle over a timed cycle, wherein the cumulative signal within the receiving means at the end of each timed cycle is representative of the actual rotational speed of the spindle. The apparatus is further comprised of a first register for receiving a first signal representative of a selected desirable rotational speed of the spindle, a second register for receiving from the receiving means a second signal representative of a percentage of the actual rotational speed of the spindle after a lapse of the same percentage of the timed cycle, means for comparing the first signal with the second signal at the end of each timed cycle, and for generating a third signal each time the second signal is greater than the first signal, and means for generating a fourth signal after receiving a predetermined number of the third signals to disable the motor which drives the spindle.

Rotational speed to impulse frequency converter

Abstract: An apparatus for converting the rotational speed of a shaft, particularly of the driving shaft of a log propeller shaft into a proportional impulse frequency is provided with a rotary permanent magnet, means to couple it with the shaft, and at least one magnetically actuated switch positioned within the effective range of the permanent magnet, these electrical elements being arranged in a liquidproof housing of an improved construction simultaneously contributing to an optimum space saving arrangement of all parts involved.

Inertial stabilising method for space vehicle - uses combination of two motor-generator electrical machines with oppositely rotating flywheels

Abstract: The space vehicle inertial stabilising method uses the storage and recovery of kinetic energy. The space vehicle uses an arrangement of two dynamo-electric machines having identical inertia flywheels. The machines rotate in opposite direction on the name axis they are linked together such that in the motor phase without vehicle drive maximum machine rotational speed is sought when their speed variation difference is zero. The system uses a busbar connected to solar cells. In the motor phase with vehicle drive. Maximum machine rotational speed is sought when their speed variation difference is imposed by a kinetic moment of the space vehicle. This moment is defined in magnitude and sense by the drive logic. This being from a constant voltage on the busbar connection to solar cells.

Experimental Observations on the Thermal Performance of a Rotating Coolant Circuit with Reference to the Design of Electrical Machine Rotors

Abstract: SYNOPSIS This paper presents the results of an investigation into the influence of rotation on the thermal and hydrodynamic characteristics of a rotating coolant circuit which has relevance to the design of cooled rotors for electrical machines. Tests conducted with a fixed pressure drop across the entire rotor circuit demonstrate that increases in rotational speed can produce consequential increases in the temperature of the simulated winding. This is true for the case where the energy dissipation is constant.

Speed change device

Abstract: A mechanical speed change device designed to occupy minimum space in the ial direction. In operation, a ball type cam follower simultaneously tracks sinuous cam grooves in the drive and driven members. The lead angles of the respective cam grooves are different so that a given axial displacement of the cam follower requires different rotational movements of the drive and driven members. Therefore a given rotational speed of the drive member produces a different rotational speed of the driven member.

Apparatus for measuring engine timing independent of speed

Abstract: The disclosure describes improved apparatus for creating a delay for stroboscopes which corresponds to a fixed rotational angle of an engine and is independent of the rotational speed of the engine. The delay is created by charging a capacitor by means of a first current source and discharging the capacitor by means of a second current source.