摘要:
A thermal-transfer recording method and an apparatus used for this method in which ink on an ink tape is heat-transferred in the form of a mirror image of a desired image to an intermediate recording sheet having a base film and an ink absorbing adhesive layer formed on the base film, and in which the intermediate recording sheet to which the mirror image has been heat-transferred is bonded to a desired recording medium at the surface of the ink absorbing adhesive layer.
摘要:
An auto-tracking method and apparatus of a helical scan type magnetic recording/reproducing apparatus wherein envelope levels of reproduced signals are detected and the running phase of a magnetic tape is controlled so that the envelope level of the reproduced signal becomes maximum after detection is effected roughly and then finely, thereby allowing a video head to scan a track on the magnetic tape.
摘要:
A motor control apparatus for driving and controlling a motor, in which a signal frequency proportional to a rotation number of the motor is converted into a d.c. voltage by a frequency/voltage converter so as to drive and control the motor by the d.c. voltage. The apparatus comprises a first, a second, and a third pulse generator for successively producing a first, a second, and a third repetitive pulse, respectively, in response to a signal period proportional to the rotation number of the motor; a constant current source; a first reset circuit driven by the third pulse to reset an output current of the constant current source; a first capacitor connected to the first reset circuit in parallel with the first reset circuit and charged by the output current of the constant current source; a sampling circuit driven by the second pulse to derive a saw tooth wave signal appearing across the first capacitor; a second reset circuit driven by the first pulse; a second capacitor connected to the second reset circuit in parallel therewith for charging the saw tooth wave signal through the sampling circuit; and a circuit for changing a pulse width of at least one of the first, second and third pulses substantially in accordance with the output current of the constant current source.
摘要:
A signal voltage dividing circuit in which two switched capacitors each including an input terminal, an output terminal and a capacitor connected selectively to the input terminal or the output terminal are connected in series and driven in opposite phase with each other. A holding capacitor is connected between the junction of the two switched capacitors and a reference potential. An input signal is supplied across the two switched capacitors to produce a divided output signal from the junction of the two switched capacitors.
摘要:
A conventional DC/DC converter with both a step-up function and a step-down function has a drawback that its output voltage will be discontinuous when its operations are switched.An error signal, which is representative of a difference between a target voltage and a present voltage, is inputted to both a step-down switching control circuit and a step-up switching control circuit. When the difference between the target voltage and the present voltage is below a predetermined value, the switchings of the step-down and step-up converters by the step-down and step-up switching control circuits, respectively, are caused to concurrently run in a time division manner.
摘要:
A video printer comprises a main memory unit for storing data of a first picture, a sub-memory for storing data for an overlay region to be overlaid on the first picture and also indicative of a second picture to be displayed in the overlay region, a memory data processing unit for generating a synthesized picture by selectively controlling the picture data for the overlay region on the basis of the data stored in the sub-memory, a system control circuit for controlling the data storage in the main memory unit, the data storage in the sub-memory circuit and operation of the memory data processing circuit, and a print circuit for producing a hard copy on the basis of the output of the memory data processing circuit.
摘要:
An apparatus for driving a brushless motor, in which a ripple appearing in the rotation torque of the motor is cancelled by driving the motor with a signal current whose phase is opposite to that of and which has a waveform symmetrical with that of the torque ripple waveform, so that the motor can rotate accurately without any speed variation. In order to obtain such a signal current waveform, counter-electromotive forces induced in the stator coils of the motor are detected, and the level of the signal indicative of the detected counter-electromotive forces is controlled depending on the load and rotation speed of the motor to provide a control signal for controlling the motor drive current.
摘要:
A transistor circuit is used as a signal amplifier which has little possibility of oscillation in an IC. The transistor circuit includes a cascade connection of differential amplifiers. Each of the amplifiers comprises a differential pair of bipolar transistors and an enhancement-type MOSFET as a constant current source. The MOSFET of each amplifier is connected in the common source mode, and the drain is connected to the emitters of the differential pair of bipolar transistors. The sources of all the MOSFETs are connected to a common ground-line.
摘要:
A power supply in which a single variable voltage supply device is used as a power source for a plurality of motors which are simultaneously or successively rotated, in which each motor is subjected to constant current driving by a current control device connected to the motor, and in which the variable voltage supply device is controlled so as to produce a voltage which is the sum of the highest one of the voltages required for driving the motors and necessary and minimum voltage with which all the current control devices are operable.
摘要:
A video printer is disclosed. An input video signal is converted into a digital signal and stored in a memory. The write/read operation and memory addresses of the memory are controlled by a memory control unit. The signal read out of the memory is converted into print data, and an image is printed by a printer. The print data and the printing operation are controlled by a print control unit, and at least a part of the memory areas of the memory is controlled in the write operation by an area control unit.