摘要:
A paper sheet material conveying device has a feed roller assembly and a temporary hampering assembly disposed downstream thereof. The sheet material conveying device includes a driven shaft to be rotated by a driving source and a driven roller mounted thereon. The driven roller has an inside diameter larger than the outside diameter of the driven shaft and is mounted rotatably on the driven shaft. When the forward movement of the sheet material fed by the feed roller assembly is hampered by the temporary hampering assembly, the rotation of the driven roller is stopped by the resistance of the sheet material exerted on the driven roller in spite of the rotation of the driven shaft.
摘要:
A speed detecting apparatus having a detector (101) for generating two sine-wave signals (PA, PB) which are .pi./2 out of phase with each other and have a frequency proportional to the speed of rotation of a motor so that actual-speed voltages (V.sub.L, V.sub.H) can be produced which are proportional to the speed of rotation of the motor. The speed detecting apparatus includes a quadrupling circuit and a frequency-to-voltage converter 107. Also included is a first speed generator for generating the actual-speed voltage (V.sub.H) in a high-speed range and a second speed generator which includes a four-phase rectangular signal generating circuit (106), a differentiating circuit (109), and a synchronous rectifier circuit (110) for producing the actual-speed voltage (V.sub.L) in a low-speed range. The voltages generated by the first and second speed generators are selectively issued as an output depending on whether the motor rotates at a high speed or a low speed.
摘要:
A novel crystalline aluminosilicate which exhibits a specific X-ray diffraction pattern having at least seven diffraction lines showing the following relative intensities at the positions of the following respective diffraction angle (2.theta.):______________________________________ Diffraction angle (2.theta., deg) Relative intensity ______________________________________ 7.8 .+-. 0.2 5-30 8.7 .+-. 0.2 90-100 8.9 .+-. 0.2 90-100 17.5 .+-. 0.2 5-30 17.7 .+-. 0.2 5-30 23.1 .+-. 0.2 30-80 23.3 .+-. 0.2 20-50 ______________________________________ Such a crystalline aluminosilicate is produced by the mutual reaction of the components of a mixture of a silica source, an alumina source, a sodium source and water in the presence of 1,8-diamino-4-aminomethyloctane. The crystalline aluminosilicate thus prepared has an excellent catalytic activity and exhibits a specific adsorption behavior. The novel crystalline aluminosilicate according to the present invention may be advantageously used as a catalyst for producing a disubstituted benzene from a monosubstituted benzene or for producing a lower olefin from methanol and/or dimethyl ether and as an adsorbent.
摘要:
An image-forming apparatus comprising an original-support plate for placing an original document thereon, a photosensitive member support stand disposed opposite to, and beneath, said original-support plate for placing a photosensitive member thereon, a charging-exposing unit for forming a latent electrostatic image corresponding to the original document on the photosensitive member, said charging-exposing unit being mounted between the original-support plate and the photosensitive member support stand for transverse reciprocation, and a power driving source for moving said charging-exposing unit reciprocally. The charging-exposing unit includes a mechanism for feeding the photosensitive member. During the return movement of the charging-exposing unit, the photosensitive member transfer mechanism acts on the photosensitive member placed on said support stand to move the photosensitive member incident to the return movement of the charging-exposing unit.
摘要:
A speed detector including a circular rotational member having a plurality of equally spaced-apart teeth on the outer circumference thereof, and first and second magnetic sensors. The first and second magnetic sensors each comprise a permanent magnet, a magnetic pole which permits the passage therethrough of a magnetic flux generated by the permanent magnet, and a detection coil wound on a portion of the magnetic pole. The magnetic poles of the first and second magnetic sensors are disposed in close proximity to, and arranged to face, the teeth on the rotational member, whereby each magnetic sensor produces an alternating output signal as the rotational member rotates, the frequency of each output signal being proportional to the speed of the rotational member. The direction in which the rotational member rotates can be detected by disposing the magnetic poles of the first and second magnetic detectors such that one of them is displaced circumferentially with respect to the other by an angular distance which is equivalent to 1/4 of the pitch of the teeth arrayed on the rotational member.
摘要:
A system for driving an alternate current motor including a pulse width modulation inverter having the two-range driving characteristics, wherein the motor is driven by the pulse width modulation output having a simulated sine wave form at the speed lower than the base speed of the motor and by the pulse width modulation output having a rectangular wave form at the speed higher than the base speed of the motor.
摘要:
An induction motor drive apparatus brings the actual speed of an induction motor into coincidence with a command speed by varying the frequency and effective value of a three-phase AC voltage applied to the induction motor and limits the torque of the induction motor in the low speed region by controlling an amplitude of a speed deviation signal below a prescribed value. The apparatus includes an inverter for generating three-phase AC voltage, a speed deviation signal generator, a torque limit signal generator, an amplitude controller for controlling the amplitude of the speed deviation signal based on the presence of the torque limit signal, a slip signal generator which generates a slip signal having a positive or negative constant voltage conforming to the rotational direction of the induction motor, an adder for adding together a voltage signal which conforms to the actual speed and the slip signal, a rectangular waveform signal generator, a multiplier for multiplying an output of the amplitude controller by an output of the adder and a pulse width modulator. The rectangular waveform signal generator is adapted to produce a three-phase rectangular signal whose frequency is proportional to the output voltage value of the adder. The rectangular signal of each phase is modulated in pulse width on the basis of the speed deviation, the inverter being controlled by each resulting pulse-width modulated rectangular signal to thereby vary the effective value of the three-phase AC voltage and to make the speed of the induction motor constant.
摘要:
An apparatus for controlling the operation of an AC motor wherein braking energy at the time of a reduction in motor speed is disposed of by regenerative braking. The apparatus includes a rectifier which is connected to the AC power source, a DC link which includes smoothing capacitors and a regenerative transistor bridge circuit, a variable voltage-variable frequency inverter. Further provided are a diode which is connected between the rectifier and the transistor bridge circuit and which is biased in the reverse direction at the time of regenerative braking, and a firing control circuit for detecting the reverse bias voltage of the diode to control the firing of each transistor in the transistor bridge circuit, the braking energy being fed back to the AC power source when the AC motor undergoes a reduction in speed. The apparatus, which provides stable regenerative operation, can be constructed simply and inexpensively, and reduced in size.
摘要:
A DC motor phase control system is provided in a system having a first controlled rectifier connected to an AC power supply and providing a positive rectified output and a second controlled rectifier providing a negative rectified output. A DC motor is controlled for forward and reverse rotation and is controlled in speed by the firing control of the rectifiers. The pulse indicating the zero point of the AC power supply voltage is delayed according to the actual speed of the motor and the delayed pulse is used as a reference pulse of the controlled firing pulses applied to the controlled rectifiers.