Showing papers on "Rotational speed published in 1982"

Rotation of cells in an alternating electric field theory and experimental proof

Abstract: Protoplasts of Avena sativa rotate in an alternating electric field provided that at least two cells are located close to each other. An optimum frequency range (20 to 30 kHz) exists where rotation of all cells exposed to the field is observed. Below and above this frequency range, rotation of some cells is only occasionally observed. The angular velocity of rotation depends on the square of the electric field strength. At field strengths above the value leading to electrical breakdown of the cell membrane, rotation is no longer observed due to deterioration of the cells. The absolute value of the angular velocity of rotation at a given field strength depends on the arrangement of the cells in the electric field. A maximum value is obtained if the angle between the field direction and the line connecting the two cells is 45 degrees. With increasing distance between the two cells the rotation speed decreases. Furthermore, if two cells of different radii are positioned close to each other the cell with the smaller radius will rotate with a higher speed than the larger one. Rotation of cells in an alternating electric field is described theoretically by interaction between induced dipoles in adjacent cells. The optimum frequency range for rotation is related to the relaxation of the polarization process in the cell. The quadratic dependence of the angular velocity of rotation on the field strength results from the fact that the torque is the product of the external field and the induced dipole moment which is itself proportional to the external field. The theoretical and experimental results may be relevant for cyclosis (rotational streaming of cytoplasm) in living cells.

Apparatus for the transfer of articles between two machines

Abstract: Apparatus is disclosed for transferring solid articles such as biscuits, without changing their position or spacing, between an upstream machine discharging the articles at a constant speed for a downstream machine having a higher rated speed with short dwells. The articles are fed from the upstream machine to a first linear conveyor and a second, parallel linear conveyor feeds in the opposite direction the articles towards the downstream machine. A circular turntable or semicircular conveyor has a semicircular path of movement between the first and second conveyors for transferring the articles therebetween. The turntable or semicircular conveyor is mounted for translation on a carriage parallel to the first and second conveyors. The translatory speed of the turntable or semicircular conveyor is equal to one-half the difference of the displacement speeds of the first and second conveyors and the rotational speed of the turntable or semicircular conveyor is such that the tangential speed thereof is equal to one-half the sum of the displacement speeds of the first and second conveyors.

Speed-responsive reversing hydraulic drive for rotary shredder

Abstract: A hydraulic drive for a rotary shredder includes a rotation-actuated electric reversing control. Such control includes a rotation sensor positioned on one of the rotational elements of the drive: one of the cutter shafts, the hydraulic drive motor shaft or the hydraulic pump motor shaft. An RPM monitor circuit receives a signal from the rotation sensor and measures rotational speed to determine existence of a stoppage or slowing of the shaft corresponding to a jamming condition. This circuit monitors shaft speed over discrete time intervals and discriminates between momentary jamming conditions by determining the duration of low shaft speed conditions. The circuit transmits a jam signal to a reversal actuator circuit upon detection of a subnormal shaft speed persisting longer than the predetermined time interval. The reversal actuator circuit includes a timer and reverse and forward solenoids on a flow-reversing valve for briefly reversing fluid flow to the hydraulic motor when a jam signal is received. Monitoring rotation at the pump motor enables the hydraulic fluid circuit, including a pressure relief valve, and the pump motor to filter out brief changes in rotation due to momentary jamming conditions and thereby aid in discriminating between true and momentary jamming conditions.

Method and apparatus for improving disk storage capacity

Abstract: Data is stored on a rotating memory disk by maintaining constant the relative velocity between the recording transducer and the recording media. The rotational speed of the disk is varied as the transducer is translated radially of the disk recording surface, the disk surface being divided into a number of concentric track zones each containing a predetermined number of tracks. For any given zone, an optimum rotational motor speed is established and the rotational speed of the disk is maintained at that zone speed when the transducer position signals specify a given zone. As the transducer is commanded to step to a different track in a different zone, the rotational speed of the disk is altered to match the new zone speed within a relatively short period of time. Once the transducer is located within the given zone, the rotational disk speed is maintained at that zone speed for motion within the zone.

Apparatus for controlling internal combustion engine

Abstract: In an apparatus for controlling an internal combustion engine in which the quantity of air supplied to the engine is controlled to control the warming-up rotational speed of the engine, a first desired warming-up rotational speed characteritic relative to the temperature of engine cooling water and a second desired warming-up rotational speed characteristic lower in rotational speed level than the former are stored in an ROM of a micro-computer, so that, when the throttle valve is not opened during warming-up of the engine, the actual rotational speed of the engine coincides with the first desired warming-up rotational speed, while, when the throttle valve is opened during warming-up, the actual rotational speed of the engine coincides with the second desired warming-up rotational speed.

Characteristics of a Slipper Bearing for Swash Plate Type Axial Piston Pumps and Motors : 1st Report, Theoretical Analysis

Abstract: A slipper bearing is one of the factors which affect significantly the performance of swash plate type axial piston machines. In this paper, considering all the oil-film parameters, that is, tilting angle, maximum tilting angle azimuth and mean clearance, a theoretical analysis on the characteristics of the slipper bearing is made from the standpoint of fluid film lubrication. As numerical examples, changes in the oil-film parameters due to a rectangular change of a supply pressure are shown. And also, the limit of fluid film lubrication is given in relation to the supply pressure and the rotational speed.

Control for tape drive system

Abstract: A control for a digital cassette tape drive maintains constant linear tape velocity at the playback head, constant tape tension, provides compensation for inertial imbalances and provides for minimal stop time Constant linear velocity is obtained by computing actual velocity at the head and using the computed information to control takeup motor speed Tape tension control is achieved by energizing the payout hub drive motor with a voltage which is a function of hub rotational speed and motor current

Automatic fan speed adjuster for combine harvester

Abstract: A combine harvester having threshing and separating mechanism, sieve through which crop material separated by the threshing and separating mechanism passes, cleaning mechanism having a fan operable to blow air through the sieve and hence clean the crop material on the sieve, the fan being driven by variable speed drive, sensor operable to sense the fore-and-aft inclination of the machine and produce a signal representative thereof, a device for selecting a nominal rotational speed for the fan during operation of the machine on level ground and producing a signal representative of that nominal speed, a device for combining the inclination signal and the nominal speed signal to produce a signal representative of the desired speed of the fan as a function of the fore-and-aft inclination of the machine, mechanism for measuring the actual rotational speed of the fan, and control mechanism responsive to the desired fan speed signal and the actual fan speed signal to produce a command signal for application to the variable speed drive, whereby the rotational speed of the fan is adjusted as a function of the fore-and-aft inclination of the machine

Speed detecting apparatus

Abstract: In a speed detecting apparatus for detecting the rotational speed of a rotating body mechanically coupled thereto, an encoder generates one cycle of a sine-wave signal each time its angular position of rotation changes by a predetermined unit amount. A zero-crossing pulse is generated at each zero-crossing point of the sine-wave signal generated from the encoder, and the phase angle of the sine-wave signal is detected on the basis of the zero-crossing point of the sine-wave signal generated from the encoder. In a high speed range, the rotational speed is detected on the basis of the ratio between the number of zero-crossing pulses and the time interval between a first one and a last one of the plural zero-crossing pulses. On the other hand, in a low speed range, the rotational speed is detected on the basis of the combination of the number of the zero-crossing pulses appearing within a predetermined period of time and the phase angle of the sine-wave signal.

Device for converting rotational kinetic energy to heat by generating eddy currents

Abstract: The converter device comprises a magnetic rotor (2) rotatively mounted integral with primary shaft (1) of the device and a heat exchanger (5) having electrically conducting walls through the helically-shaped inner cavity (6) of which a fluid is caused to flow and within the walls of which rotating induction produced by a rotor generates eddy currents. A tachometer generator (8) measures the shaft rotational speed and controls, as a function of the said speed, the angular position of an electric motor (9), which drives the exchanger (5) along a linear translation path in a direction parallel to the rotor axis. Due to such a closed-loop control, the resistant torque is governed by a predetermined relation. The device can be used to convert to heat rotational kinetic energy from a wind turbine.

Optimum shift position indicating device of vehicle

Abstract: The optimum shift position indicating device of a vehicle comprising: a vehicle speed sensor for detecting a running speed of the vehicle; an engine rotation sensor for detecting a rotational speed of an engine; an engine load sensor for detecting an engine load; an operational circuit in which a driving power at present is calculated from an engine torque obtainable from the engine rotational speed and the engine load, subsequently, required engine torques at respective shift positions are calculated from the driving power, further, fuel consumption rates at the respective shift positions are obtained from the engine rotational speeds and the required engine torques at the respective shift positions, and information on the optimum shift position where the best fuel consumption rate is obtainable is outputted; and shift position indicating elements for indicating an output from said operational circuit; and capable of giving a driver the information on the optimum shift position where the best fuel consumption rate is obtainable during running condition at present.

Fuel injection control in an internal-combustion engine

Abstract: In the control of fuel injection in an internal-combustion engine, whether or not the rate of change of the engine rotational speed exceeds the selected limit of the rate of change of the engine rotational speed, determined by the ratio of the engine rotational speed to the automobile speed and the ratio of the intake air amount to the engine rotational speed, is checked. The value of the engine rotational speed used in the control of the fuel injection pulse width and the ignition timing is restricted to within the selected limit of the rate of change of the engine rotational speed.

Method of producing an extrudate of controlled size and shape from a roller die

Abstract: A method of producing an extrudate using a roller die is disclosed in which on-line adjustments are made to size and shape deviations by changing the rotational speed of the extruder screw, the feed rate to the extruder, or the speed of the take-away device and the rotational speed of the roller die. The size and shape dimensions of the extrudate are measured and used to calculate new values for the screw or take-away speed of the feed rate and the roller die speed. A measurement of the extrudate dimensions may also be obtained at the roller die to provide a faster response.

Control device for a hydrostatic transmission

Abstract: An apparatus for use in controlling a variable displacement pump in a hydrostatic transmission comprises servo-positioning means for varying the displacement of the variable displacement pump, signal producing means for producing a first signal dependent on the rotational speed of the input shaft of the variable displacement pump and means communicating the first signal dependent on the rotational speed of the input shaft to the servo-positioning means to increase or decrease the displacement of the variable displacement pump as the rotational speed of the input shaft increases or decreases. A second signal dependent on the output pressure of the variable displacement pump is communicated to the servo-positioning means to act in opposition to the first signal to tend to reduce or increase the displacement of the variable displacement pump.

Means for limiting rotation speed of a vertical shaft wind turbine

Abstract: Means for limiting rotational speed in a vertical shaft wind turbine (1) having a central hub (3) and spokes (4) extending therefrom. Spokes lying over each other support at their ends turbine blades (6) placed concentrically around the turbine shaft. Each turbine blade (6) is pivotable around a vertical axle (CA), and a leaf spring bundle (10) is in each spoke placed between the turbine blade and the base of the spoke in order to adjust, when the turbine is at a rest, the turbine blade chord angle (β) in to a predetermined position and taking an unloaded state in which its center of gravity (CG) is located near and, as seen in the direction of rotation of the tubine, behind a plane (15) through the symmetry axis (CB) of the turbine shaft and the pivot axle (CA) of the turbine blade. The pivot axle (CA) of the turbine blade has such a position that the torque of the wind forces (P) around the pivot axle is reduced to a minimum. The spring bundle (10) is dimensioned to exert a great resistance to deflection when the turbine rotates at operation speed, the chord angle of the turbine blade thereby remaining essentially unchanged, and in order to deflect gradually and faster and faster at higher rotation speeds beyond operation speed resulting in a readjustment of the turbine blade (6) in a direction for limiting the rotation speed.

Modal testing of a rotating wind turbine

Abstract: A testing technique has been developed to measure the modes of vibration of a rotating vertical-axis wind turbine. This technique has been applied to the Sandia Two-Meter Turbine, where the changes in individual modal frequencies as a function of the rotational speed have been tracked from 0 rpm (parked) to 600 rpm. During rotational testing, the structural response was measured using a combination of strain gages and accelerometers, passing the signals through slip rings. Excitation of the turbine structure was provided by a scheme which suddenly released a pretensioned cable, thus plucking the turbine as it was rotating at a set speed. In addition to calculating the real modes of the parked turbine, the modes of the rotating turbine were also determined at several rotational speeds. The modes of the rotating system proved to be complex due to centrifugal and Coriolis effects. The modal data for the parked turbine were used to update a finite-element model. Also, the measured modal parameters for the rotating turbine were compared to the analytical results, thus verifying the analytical procedures used to incorporate the effects of the rotating coordinate system.

Method and apparatus for determining rotational speed

Abstract: A method and apparatus are disclosed for providing improved rotational speed determination for a rotating shaft. Two probes positioned adjacent a circular disk which rotates with the shaft scan markings on the disk and generate four out-of-phase signals in response to rotation of the shaft. A switch, controlled by logic circuitry which detects intersections of the signals, develops a composite saw-tooth-shaped signal from the four signals. A counter counts the number of crossings of the composite signal with a reference "zero" value to develop a determination of the number of discrete angular positions traversed by the shaft during a specified time interval. A memory stores the value of the composite signal at the start of the time interval. Computation circuitry develops a rotational speed based on the counted number of positions, corrected by a factor derived from the difference between the stored value and the value of the composite signal at the end of the interval. Time control circuitry prevents the start or end of the time interval during switching and prevents switching during the start or end of the time interval.

Half speed balancer

Abstract: A half speed balancer for unbalanced mechanisms such as internal combustion engines comprises an Oldham coupling device with a central coupler that orbits in a curved (usually circular) path at a frequency twice the speed of the coupling rotation. The balancer substitutes for an equivalent rotating eccentric weight when driven at only half the rotational speed thus causing reduced bearing friction and noise and may be used in multiples like eccentric weights to offset various unbalance conditions.

Effects of Rotation and Blade Incidence on Properties of Turbomachinery Rotor Wake

Abstract: An experimental investigation of the effects of the speed of rotation on a turbomachinery rotor blade wake was conducted using a fan rotor in incompressible flow. Measurements were made at two different rotational speeds (1753 and 1010 rpm) with the same blade incidence angle. The blade incidence angle was also varied to discern the effect of blade loading. A three-sensor hot-wire probe mounted in a stationary frame of reference was used for the measurements made at several radial and axial stations in the near- and far-wake regions. The three-dimensional mean velocity and turbulence profiles, the wake defect, wake decay rate, turbulence intensities, and turbulence stresses are appreciably altered when the speed of rotation and the blade loading are changed. The wake defect is reduced and the radial velocity increased when the rotation speed is increased.

Peak combustion pressure controlled spark timing control system with engine speed dependent filter

Abstract: In a combustion timing control system of the type wherein peak combustion temperature is sensed and combustion initiation timing is adjusted in closed loop to maintain peak combustion pressure at a desired constant crankshaft rotational angle, the combustion pressure signal is processed in apparatus having differentiating elements with a first time constant, smoothing integrating elements with a second time constant and further elements effective to vary both first and second time constants inversely with crankshaft rotational speed, wherein signal to noise ratio is optimized over the entire range of said speed.

Hydraulic control system for industrial vehicle

Abstract: The rotational speed of a hydraulic pump motor for a fork lift hydraulic control system is varied basically in accordance with the displacement of spools of manual control valves to allow the pressure supplied to servo cylinders to be smoothly increased. The rotational speed may also be varied in response to additional parameters such as the load to be moved by the servo cylinders, the amount of displacement of the load and the rate at which the spools of the manual control valves are moved to provide improved start free safe load handling characteristics.

Apparatus for producing a constant rotational speed from a variable speed input

Abstract: There is disclosed method and apparatus for converting a variable rotational input speed to a predetermined substantially constant rotational output speed, for purposes in which a constant speed is necessary e.g. the driving of a constant frequency A.C. generator. The apparatus comprises an epicyclic gear having an input member 14 arranged to be driven by a power source 1 at a rotational input speed which may vary, an output member 16 from which predetermined substantially constant rotational output speed can be taken, and a reaction member (sun wheel S). Monitoring means 30, 31 is arranged to respond to fluctuations from a predetermined value in the rotational speed of the input member, and control means 9, 21 is coupled with the reaction member and controllable by the monitoring means in order to vary the relative rotation between the reaction member and the other members of the epicyclic gear. Thus, the monitoring means and the control means serve to maintain a substantially constant predetermined output member when fluctuation occurs in the speed of the input member.

Correction of irregularities of fuel controlling amount by engine cylinders

Abstract: PURPOSE:To make it possible to correct the amount of fuel injection by cylinders by a method wherein in the case of a fuel injection device for an internal- combustion engine, the amount of fuel injection by cylinders is corrected in proportion to the difference between the average engine rotation speed and the engine rotation speed corresponding to each of the cylinders. CONSTITUTION:When the amount (e) of fuel injection by cylinders becomes irregular as a result of irregularities of the surface areas of the openings of fuel injection valves among the cylinders occurring due to a manufacturing tolerance or a secular change, the engine rotation speed becomes irregular as shown by the left hand side graph (a). To overcome such difficulties, a study amount K1 is first obtained on the base of the difference between the average value N of the engine rotation speed and the actual engine rotation speed N1 as shown by the right hand side graph (c) and then the fuel controlling amount T1 is corrected for each of the cylinders as shown by the right hand side graph (d). As a consequence, the amount (q1) of fuel supply becomes equal for each of the cylinders as shown by the graph (e).

Speed sensor and method for producing same

Abstract: A rotational speed sensor (10) comprising a shaft (54) having a reluctor (50) mounted thereon and coacting with a complementary shaped stator (18). The reluctor (50) and stator (18) have coacting regularly spaced projections (20, 58) which are magnetizable so that as the reluctor (50) rotates with the shaft (54), there is developed a cumulative voltage output which in turn enables utilization of much greater air gaps between the respective projections (20, 58). Because of the greater latitude in the air gaps, it is possible to construct a variable reluctance speed sensor (10) much more economically and with less emphasis on cumulative manufacturing tolerances. This greater flexibility of manufacturing with higher manufacturing tolerances contributes materially to the attainment of an economical and reliable speed sensor.

Comparison of the Unbalance Responses of Jeffcott Rotors With Shaft Bow and Shaft Runout

Abstract: The unbalance response of a Jeffcott rotor with shaft bow and/or runout was theoretically and experimentally studied. Included in the theoretical model is the capability of low-speed response compensation, such that the response at low speed can be vectorially subtracted from the total response at any rotational speed. Responses of rotors with equal amounts of bow or runout are shown to be significantly different in both Bode and Nyquist forms. A small scale lightly damped Jeffcott rotor rig was also tested. The magnitude and angular position of the shaft bow were parametrically varied. The vibration data from the rotor tests were plotted using a synchronous tracking filter by two methods: both not using and using low speed 15 refs.

Idling speed controlling system for internal combustion engine

Abstract: Feedback control is carried out to maintain the rotational speed of an internal combustion engine during idling at a desirable speed determined according to the operating conditions of the engine by controlling an adjusting valve for controlling the amount of air to be fed to the engine. The actual rotational speed of the engine and the actual opening angle of the throttle valve are detected and when the actual rotational speed is lower than a predetermined value and at the same time the actual opening angle of the throttle valve is smaller than a predetermined value, the feedback control is carried out. Further, whether or not the driving power of the engine is operatively transmitted to the driving wheels is detected, and the predetermined value for the rotational speed of the engine is set at a higher value when the driving power is not transmitted to the driving wheels than when the driving power is transmitted to the driving wheels.

Yarn winding apparatus

Abstract: A spindle drive type winding apparatus wherein a spindle onto which a bobbin for winding a yarn thereonto to form a yarn package is inserted is driven so that a predetermined winding factor is controlled in accordance with a predetermined program. The spindle drive type winding apparatus is provided with a control device which comprises: a peripheral speed detector for detecting the peripheral speed of the yarn package and generating a peripheral speed signal; a control for controlling the rotational speed of the spindle and generating a control signal; a circuit for calculating the wound amount of the yarn package based on the peripheral speed signal emitted from the peripheral speed detector and the signal emitted from the control and for generating a radius signal; and a function generator for emitting a programmed winding signal obtained in accordance with a pattern based on theradius signal emitted from the calculating circuit. The winding factor may be a peripheral speed of the yarn package, and in this case the peripheral speed is detected by means of the peripheral speed detector. The winding factor may be tension in wound yarn, and in this case the tension in yarn is detected by means of a tension detector. The winding apparatus may be driven at a constant wind ratio or at a constant wind angle.

Turbine engine power optimization control system

Abstract: Pushbutton controls are provided for the power management of a turbine powered aircraft; and these pushbuttons may be mounted on the aircraft pilot's control handwheel. The turbine engine has a maximum rated permissible rotational speed which initially increases with increasing air temperature and with increasing altitude or reduced pressure; and has an absolute maximum limitation, with this maximum permissible rotational speed decreasing at increasing temperatures starting at about 10 or 15 degrees below zero, centigrade; and these limitations are reduced when supplemental equipment such as de-icing equipment is turned on. In accordance with the present invention, a series of "maps", or rotational speed control characteristics reflecting the factors mentioned above, are provided, and the pushbutton controls select among these characteristics, with the "take-off" power button permitting the highest maximum speeds, etc. In addition, automatic timing to reduce the maximum power levels, such as "Take-Off" power or "Performance Climb" power, is provided, to avoid over-stressing the turbine engines. The system may include additional arrangements for limiting the maximum allowable rotational speed of the turbine engine to a speed below that indicated by any of the "maps", when certain pushbuttons such as the "Approach" pushbutton is actuated.

Control apparatus for friction clutch

Abstract: PURPOSE:To prevent seizure of a friction plate and valve sticking due to the resultant dust of worn plate by releasing friction clutching when such a condition has continued for the time longer than the fixed period that the difference value between the rotation speed of an input side and an output side is higher than the level CONSTITUTION:A slip speed operation circuit 123 calculates the slip speed (s) between a turbine rotation speed Nt and an engine rotation speed Ne detected by the voltage pulse generated in the primary winding of the ingition coil of an engine 1 through a rotation speed detector device 141 A target value setting circuit 124 sets the slip speed target value (So) according to the turbine rotation speed Nt and intake manifold negative pressure detected by an engine load detecting device 140, variation of calculated value S-So given from a variation calculating circuit 125 is sent to a comparator 131 When said value is raised over the fixed level for a certain period, an output signal is transmitted to shut off the pulse current supply to a clutch solenoid 112

Apparatus and method for controlling and mixing a liquid subjected to a centrifugal force

Abstract: An apparatus for controlling and mixing an the influence of centrifugal force in a rotating about an axis element, in particular the rotor of a centrifugal analyzer exposed to fluid flow, the amount of liquid to be controlled has a limited volume. In the flow channel (36, 41) for the liquid, at least one storage chamber (38) is provided whose volume is greater than the maximum volume of liquid. It is shaped so that the liquid remains at a rotation of the element with a sufficiently high first speed in it. With the storage chamber (38) is an outlet channel (40) in connection which is guided and arranged such that at least a portion (76) thereof lies radially closer to the axis of rotation than the fluid surface during the rotation with the first speed. Its walls (64, 65, 66) consist of a wettable by the liquid material. Its cross-section is designed so that the liquid at a second speed which is less than the first rotational speed, driven by boundary surface force into the outlet channel (40) penetrates. Further, a corresponding method is described.