Showing papers on "Rotational speed published in 1977"

Mathematical Model of the Torque Characteristics for Hydraulic Motors

Abstract: In the mathematical model described in this paper, the following friction components are considered: (1) friction torque proportional to operating pressure, (2) viscous friction torque proportional to rotational speed and viscosity of fluid and (3) constant friction torque independent of operating conditions. The friction component which is proportional to operating pressure decreases with an increase of the rotational speed. This effect is also considered in this model. Therefore this mode can represent the whole torque performance from start to maximum speed.

Roller conveyor system having speed control

Abstract: A free wheeling tire having the ability to resist increased rotational speed under load is comprised of a hub portion, rim portion, and a multiplicity of flexure members defining voids extending continuously from one side of the tire to another. Deleterious heat generated during operation is successfully dissipated through the increased surface area provided by the voids and by the nature of geometrical element configuration. The tires are placed in a gravity roller conveyor in arrays where each array may have different speed control characteristics permitting variations in speeds of objects as they move from one array to another.

X-Ray tube control system

Abstract: A control system for rotating anode x-ray tubes comprising an x-ray tube including an anode rotated by a motor having mounted therein photoelectric means for sensing rotational movement of the anode, and circuit means electrically connected to the tube, the photoelectric means, and the motor for regulating operation of the tube and rotational speed of the motor in accordance with parameters selected for operation of the tube.

Ignition system for internal combustion engine

Abstract: The angle through which the crankshaft of an engine rotates within any given time is proportional to the rotational speed of the engine. Consequently, where the ignition system is of the type in which the integrated value of an integrator circuit or the count value of a counter circuit is varied so as to control the spark advance, if the rate of increase or decrease of the integrated value or the count value within a portion of the increasing or decreasing time is made different from that within the remaining portion of the time, the integrated value or the count value is directly affected by the engine rotational speed. In other words, the spark advance is directly controlled by the factor of the engine rotational speed, thus ensuring satisfactory response characteristic and accuracy for the ignition system.

Rotational speed detecting apparatus for electronically-controlled fuel injection systems

Abstract: A rotational speed detecting apparatus for controlling the operation of an electronically controlled fuel injection system in accordance with the rotational speed of an engine. A reference pulse generator is connected to generate a reference pulse signal in synchronism with a pulse signal which is generated by the fuel injection system in substantial synchronism with the rotation of the engine. The reference pulse generator is further connected to change the time width of the reference pulse signal in response to the operation of a starter motor and a throttle valve so that it represents the predetermined rotational speeds of the engine. A comparison circuit is connected to compare the one cycle period of the pulse signal with the time width of the reference pulse signal. The output signal of the comparison circuit is applied to the fuel injection system so that it controls fuel enrichment and fuel cut-off operation of the fuel injection system.

Tape position measurement in cassette - involves determination of rotational speed of reel and electronic processing of data

Abstract: The reels are pref. those mounted in a standard cassette, and magnetic tape is wound from one reel to the other. The speed of one reel is measured; the speed of the other reel may also be measured and the measurement result is applied to a processor to which a variable depending on the take thickness is also applied. If speed is measured on one reel only, a further variable is applied to the processor, representing a function of the tape speed transport. The processor calculates then the tape length on one of the reels, or the tape playing time, and its signal is applied to a control device and/or a display device. Code markings (5) are used as an aid to speed measurement.

Variable speed gear ratio transmission apparatus

Abstract: The variable speed gear ratio transmission apparatus of the present invention provides input differential means for dividing an input rotational force into two rotational components, output differential means for combining the divided component rotational forces, input and output shafts geared to the respective differentials, and a variable load inhibitor mechanism coupled to one of the divided rotational components for varying its rotational speed, thereby reciprocally varying the magnitude of the other divided rotational component, with the result of providing an infinite selection of speeds between the operative speed limits of the apparatus. The variable load inhibitor mechanism preferably includes planetary gears connected by brackets, each separately engaging a stationary ring gear, one of which planetary gears is geared to the input divider differential and the other of which is geared to means for determining the load to be placed on the variable load inhibitor mechanism.

Electronic engine controller

Abstract: PURPOSE: To make it possible to apply to different types of engines through a simple circuit a controller for synthetically controlling the engine. CONSTITUTION: Signals indicating the rotational speed and loaded condition of the engine are supplied from detectors 96, 16, 84, 24, to a multiplexer 122 of an input/output unit 120. The quantity of injected fuel and the quantity of spark advancement are calculated by a CPU 114 and then set on reference registers of a pulse output unit 126, wherein these quantities are compared with values stored in registers for retaining the instantaneous conditions of the engine. A fuel injection valve 66 and an igniter 40 are controlled depending on the results of the comparison. When a key switch is turned on, predetermined values are set in the reference registers by a starting program stored in a ROM 118 COPYRIGHT: (C)1979,JPO&Japio

Heat source system

Abstract: PURPOSE: To provide a heat source system, in which a compressor motor is driven at a high speed and at a variable speed, through the control of an inverter that produces a higher frequency than commercial power source, so as to change refrigerating capacity of the compressor to meet with the load, whereby it is enabled to improve efficiency of operation. CONSTITUTION: When operating torque Tc of compressor 3 is almost exceeds, for instance, point K 1 in the attached graph of characteristic curve, rotational speed of motor 4 is lowered by the function of a first torque controlling circuit 39. On the other hand, when compressor 3 is operated under the condition of point K 1 and shaft torque TM of motor 4 takes characteristic curve TM 2 in response to the change of speed instruction signal Vs, operating point of compressor 3 is shifted along the broken line shown in the drawing and compressor 3 is operated at point K 2 on characteristic curve TM 2 for a certain while. Subsequently, operation of compressor 3 is continued at point K 3 on the curve TM 2 , by the function of a second torque controlling circuit 40 and through stabilization of refrigerating cycle. Thus, it is prevented that operating torque becomes excessively large and thus it is enabled to stabilize the operation of compressor system. COPYRIGHT: (C)1979,JPO&Japio

Water powered generator

Abstract: In the illustrated embodiment a hollow armature core is rotatably mounted in a water main, and is caused to rotate by water pressure applied against flexible sensing vanes, which are affixed in an axial bore in the armature core. Rotational speed of the armature is determined by the flow rate or pressure of the water in the main, fluctuations in such pressure causing corresponding flexure and angular variation in the vanes, thereby to effect rotation of the armature at a constant speed. The generating unit incorporating the unique rotor becomes an integral part of the existing closed water conveyance system.

Control system for a motor having a shunt field winding

Abstract: Control system for a motor having a shunt field winding is disclosed. In an electric vehicle, when an accelerator pedal is stepped on at the start, a field current is increased to increase the rotational speed of the motor in accordance with the stepped angle of the pedal. In the operating region where the rotational speed of the motor is not increased in accordance with the increase of the field current, an armature current is in turn increased and inversely the field current is decreased in order to further increase its rotational speed. Thus, an impact at the start can be reduced.

Real-time recording of fatigue damage

Abstract: In the case of those rotating components of rotary machines which are cyclically stressed as their rotational speeds are cyclically varied such as aero gas turbine engine components, the cumulative total number of stress cycles which each component receives due to such speed variations is a reliable indication of its elapsed fatigue life. The invention provides a method and a digital circuit arrangement which facilitates real-time recording of the elapsed fatigue lives of such components: a component's rotational speed is continuously monitored and each time the speed cycles through any one of a plurality of predetermined speed bands, a corresponding predetermined number of fatigue life units is added to an accumulating total of such units.

Method of regulating multistage axial compressor output and an axial compressor for carrying same into effect

Abstract: A method of regulating the output of a multistage axial compressor having two coaxial rotors in series. The regulation of the compressor output is effected by varying the head of the medium to be compressed, the variation of the head of the medium being effected, after the medium leaves the stator, by changing the rotational speed of the first rotor, the speed of the second rotor being kept constant. The first rotor is connected to a variable-speed drive motor and the second rotor is connected to a constant-speed drive motor.

Device for controlling the rotational speed of turbo-jet engines

Abstract: The commanded rotational speed is compared with the actual rotational speed to produce a deviation signal. This deviation signal is multiplied by a coefficient which is determined by state variables (speed and intake pressure) of the engine and a proportional component plus an integral component of the multiplication product is employed as a control signal. This control signal is checked to make sure that it is outside critical engine states associated with the actual performance of the engine. On this control signal is superposed a signal representing the steady-state fuel flow associated with the commanded rotary speed (or under some circumstances the actual rotary speed) to determine the fuel flow rate to the engine.

Method and apparatus for producing an analogue output proportional to rotational speed employing digital to analogue conversion

Abstract: A system and method for measuring the rotational speed of a variable speed drive shaft for a ship or the like with high accuracy over a wide range of speeds. Means associated with the shaft sense the time interval for each turn of the shaft, or fraction thereof. Such time interval is accurately measured and then converted to an r.p.m. value. Steps in the method include counting the number of cycles of an oscillating signal in binary form to measure the time interval for each turn, selecting a most significant portion of bits within the number counted, determining the positional weight of the most significant bit to obtain a scaling factor, and producing a voltage inversely proportional to the value of the selected portion of bits, which voltage is then scaled by the scaling factor.

Cam grinding machine

Abstract: A cam grinding machine rotates a workpiece by using a servomotor which is capable of being rotated at a variable speed A memory device stores data of rotational speeds of the workpiece corresponding to angular positions thereof in order to maintain the circumferential speed of the workpiece constant A detecting device detects an angular position of the workpiece A counter is responsive to the detecting device and reads out rotational speed data stored in the memory device in order to apply the same to the servomotor

On the extensional vibrations of rotating bars

Abstract: The extensional equations of motion for a cantilever bar rotating about an axis fixed in space are derived. It is shown that the form of the non-linear strain-displacement relation is important in determining the nature of the relationship between the frequency of extensional oscillations and the rotational speed. In particular, the frequency may or may not increase monotonically with rotational speed, depending on the degree of hardening in the effective extensional spring. The determination whether an instability occurs as the rotational speed increases is beyond the limits of engineering beam theory.

Closed loop rotational speed control system having means for generating a PNM signal for an electric motor

Abstract: A PNM (pulse number modulation) signal is generated in response to a DC signal the magnitude of which is in proportion to the detected rotational speed of an electric motor to regulate a period of time for which an electric power is fed to the motor by switching the electric power in accordance with the PNM signal. The switching frequency is arranged to vary depending on the variation of the load of the motor.

Method for the determination of the axial thrust of roller bearings

Abstract: A method for the determination of the axial thrust of roller bearings under extreme operating conditions, which includes determining the variation in the rotational speed of the bearing cage, and employing the obtained value as a measure for calculating the axial thrust. The method employs sensors, such as strain gauge strips, applied to a stationary portion of the bearing to obtain the cage rotational speed through the dynamic deflection of a bearing weak point formed in that portion of the bearing.

Apparatus for abating noise in axial blower

Abstract: In an axial blower, the noise generated by the blower increases generally in proportion to the increasing number of rotations of the blower's rotor. It has been ascertained, however, that over a given range of rotational speeds, the magnitude of noise plotted in a graph as the function of the rotational speed describes not a smooth curve but a zigzagging curve, indicating that zones of rotational speeds producing high levels of noise and those producing low levels of noise are distributed irregularly. When the axial blower is required to be operated within an operatively permissible range of rotational speeds, therefore, the noise generated by the blower can be abated to the fullest extent without entailing any reduction in the operational efficiency of the blower by means of a system which follows the change in magnitude of the noise generated by the blower as the rotational speed of the blower's rotor is sequentially changed little by little from one boundary to the other of the said range, compares the magnitudes being registered, determines the particular rotational speed that produces the lowest level of noise within the range and fixes the operation of the blower's rotor at that particular rotational speed.

Permanent magnet latch for speed switching device

Abstract: A speed switch for a motor has an electrically conductive disc which rotates with the rotor of the motor. A drag member adjacent the disc is mounted for limited pivotal movement and has a permanent magnet linked magnetically with the disc to cause electromagnetic interaction resulting in a force on the drag member which varies with the speed of rotation of the disc. A switch is operated by a movement of the drag member to actuate an alarm or to actuate a protective device for the motor. An improved latching means restrains the drag member from movement until a predetermined rotational speed of the disc is reached. A screw is mounted so that it can be advanced into the gap and withdrawn therefrom to provide a finely adjustable magnetic shunt. The adjustment of the shunt varies the magnetic latching force and thereby the speed causing actuation of the switch.

Zero-hysteresis engine rpm limiter

Abstract: Apparatus for limiting the rotational speed of an internal combustion engine by monitoring the time interval between ignition impulses produced when a breaker switch in the primary circuit of the ignition coil opens. A pair of sequentially operable timers are started for each ignition pulse with the second time interval enabling a delay means coupled between the source of pulses and a control gate of a controlled switch connected across the breaker switch through an impedance. When a following pulse occurs during the second time interval, indicating a limiting rotational speed, the slightly delayed pulse triggers the controlled switch and the ignition pulse is shunted through the impedance with the resulting secondary voltage in the ignition coil being insufficient to cause a spark, thereby limiting the speed of the engine.

Electromagnetic tacho-generator for speed and direction indication - has two phase-shifted meander windings for speed-direction analogue output

Abstract: The electromagnetic tacho-generator provides an a.c. output proportional to both rotational speed and direction of rotation. The rotor (1) comprises a disc whose circumference is built from radial permanent magnets with alternate north and south poles (2). The stator (4) has upper and lower meander-shaped windings arranged so that they are cut by the complete magnetic flux from the rotor magnets. The windings may be in the form of printed circuits in a laminated carrier strip. The windings are slightly staggered. The output AC waveforms from the two windings will vary in frequency and amplitude in proportional to the rotor speed and their phase difference will indicate the direction of rotation.

Rotational speed transducers

Abstract: A rotational speed transducer comprises a member which is mounted to rotate at a speed related to a rotational speed input. A lamp and a photocell are mounted in relation to the rotatable member such that light from the lamp is only reflected by the rotatable member toward the photocell each time a reflector portion or portions of the rotatable member comes into a particular position or positions with respect to the lamp so as to provide an electrical output, from the photocell, which is a measure of the rotational speed input. The reflector portions may be portions of a disc which constitutes the rotatable member.

Cam grinding apparatus with means to maintain the grinding speed constant

Abstract: A cam grinding apparatus has a base member, a rocking bar rockably mounted on the base member, a master cam shaft rotatably mounted on the rocking bar, and a drive motor for driving the master cam shaft in rotation. A cam shaft to be ground is supported by the master cam shaft so as to have the cam section thereof ground by a grindstone while being rocked by the rocking bar and rotated by the master cam shaft. There is provided at least one device for detecting the rotational angle of the drive motor and for detecting the phase angle of the rocking bar. The apparatus has a rotational speed command device responsive to output signals from the detecting for generating a step-like voltage waveform representing a desired rotational speed of the drive motor, and a rotational speed control device responsive to the step-like voltage waveform for controlling the rotational speed of the drive motor so that the circumferential speed of the cam section of the cam shaft at the contact point between the cam section and the grind stone can be kept substantially constant.

Control installation for the idling rotational speed of internal combustion engines

Abstract: A control installation for the idling rotational speed of internal combustion engines, in which a by-pass control valve is provided that is controlled by an actuating device dependent on the suction pipe pressure and is located in parallel to a throttle valve which can be selectively actuated; the opening cross section of the by-pass valve which increases with increasing suction pipe pressure, thereby increases progressively.

Automatic firearms with external motor

Abstract: This disclosure relates to an automatic firearms having a rotatable drum with helical grooves therein so arranged as to cause a follower guided by said grooves to reciprocate at a speed proportional to the rotational speed of the drum. The reciprocation of the follower causes the breech mechanism to reciprocate between loading and firing positions. The drum is driven by means independent of the propulsion energy of the projectiles fired, and therefore, may be operated at varying speeds by means such as an electric motor or even by hand.

Method of and apparatus for rolling band steel

Abstract: PURPOSE:To accomplish free control of the temper and correction of the shape through rolling with tension bending by bridle rolls, with a variable rotation speed and relative position of the tension bridle rolls, in temperaed-rolling of thin band steels. CONSTITUTION:In tempered-rolling of a thin babd steel 3 with a tempered-rolling mill having two four-stage than the upper roll 1 rotating at a circumferential speed V0. The band steel 3 is wound around the upper roll 1 and the lower roll 2 in such a manner as to follow the speed V1 of the lower roll 2 at the outgoing side and the speed V0 of the upper roll 2 at the incoming side. Accordingly, when passing through the pair of the rolls, the band steel 3 is elongated for to V1 on the roll 2 from V0 on the roll 1, thus reducing the thickness thereof to the final h1=h0(V0/V1) from the initial value h0. Herein, the required value of the final thickness h1 can be freely controlled by a roll speed controller and a roll positioning apparatus.

Engine rotatonal speed setting circuit

Abstract: PURPOSE: To provide an engine rotational speed setting circuit which can produce an engine rotational speed set signal corresponding to a desired set speed of rotation of the engine in accordance with the temperature of cooling water of the engine. COPYRIGHT: (C)1979,JPO&Japio