摘要:
A power source circuit is provided having a high frequency transformer 16, a switching control circuit 15 connected with the primary winding of the transformer 16, rectifier circuits 17, 18 and 20 connected with the secondary winding of the transformer 16 for outputting a D.C. voltage to an external circuit, an alarm detection circuit 25, an excess current detection circuit 26, and an excess current detection delay circuit 28. When the alarm detection circuit 25 detects an excess current in supplying power source, the power source supply is suspended by turning off the output of the switching control circuit 15 after the lapse of the preset time. When the excess current flows after the lapse of the initial preset time t.sub.s from turning on the power source, the excess current detection circuit 26 detects it so that the output of the switching control circuit 15 is turned off.
摘要:
A fixing unit fixes a developing material deposited on a recording medium by heating and pressing the recording medium. The fixing unit includes a first number of heating members that apply heat to the recording medium and a second number of switches that supply electric power to the first number of heating members. Each of the heating members receives electric power through a series circuit of the switches. Each of the switches responds to a surface temperature of a corresponding one of the heating members so that when the surface temperature exceeds a predetermined value, the electric power is shut off.
摘要:
An electromechanical actuator includes an electric motor and a control and drive circuit mounted integrally with the electric motor. The control and drive circuit includes a serial-to-parallel converter for converting a control signal in the form of serial data into parallel data, and a device responsive to the control signal in the form of parallel data for producing a drive current or voltage for the electric motor. A system for accessing or controlling a plurality of such actuators by commands from a main controller can include a control and drive circuit which is integral with the motor itself.
摘要:
A flexible cable has a grounding pattern or patterns provided therein. Thereby, when an object having static electricity of high voltage is caused to approach the flexible cable, dielectric breakdown of a base and cover of a high polymer material of the cable, to a conducting portion of the cable which is not exposed at the interior of the flexible cable is prevented, and damage to an electronic circuit connected with the not exposed portion, due to electric discharge, can be prevented by causing the static electricity to be discharged to the exposed grounding pattern.
摘要:
According to a method of adjusting a head gap, a wire dot head is set to a predetermined position of a reference head gap; a printing pattern for detecting printing time is printed by a plurality of pins; reference printing times of respective pins are detected. Next, a test printing is performed with test printing dots previously selected from printing data, and printing time of the test printing is detected. Then, the thickness of the printing media is calculated based on the reference printing time and the printing time of the test printing. At that time, a rule of thumb in which the difference of the printing time corresponds to the difference of the head gap, is used. Then, a shift amount of the wire dot head is calculated for setting the head gap to an optimum value according to the thickness of the printing media, and gap shifting mechanism shifts the wire dot head by the shift amount. This leads to highly accurate detection of the head gap and improves printing quality thereof.
摘要:
A drive system for a wire dot head is provided with sensors for detecting displacements of corresponding print wires. Each sensor outputs a movement initiation timing signal and an impact timing signal for the corresponding print wire. An electric current to be fed to an associated coil is normally controlled by these timing signals. It is detected whether these timing signals are obtained in a predetermined time period. If not, electric power is continuously fed to the coil or is forcedly cut off so that the timing signals are obtained within the predetermine time period.
摘要:
Printing control includes determining printing dot density of print data to be supplied to a printing head, averaging the printing dot density during a predetermined period of time based on the printing dot density determined, selecting a printing speed in response to the average value of printing dot density, and controlling printing to print at the selected printing speed.
摘要:
In a wire-dot impact printer having a capacitance detector for detecting a displacement of each armature by a sensor electrode arranged opposite the armature, a space is formed between each sensor electrode and its associated armature, and a shield pattern is formed with a small space left around each sensor electrode. The shield pattern is fed with a potential at least equal to the potential of each sensor electrode. This makes it possible to reduce the influence of noise upon detection of a capacitance by the capacitance detector. A noise canceling electrode is also disposed around each sensor electrode and is connected to the sensor electrode, whereby a noise canceling circuit is further provided to eliminate noise voltage. The noise canceling circuit can eliminate a noise voltage picked up by the sensor electrode and the noise canceling electrode.
摘要:
A fixing unit fixes a developing material deposited on a recording medium by heating and pressing the recording medium. The fixing unit includes two heating members that apply heat to the recording medium and two temperature-sensitive shutoff devices. The two temperature-sensitive shutoff devices are connected in series with a corresponding one of the heating members. Each of the temperature-sensitive shut-off devices includes a first heat-sensitive shut-off element and a second heat-sensitive shut-off element. The first heat-sensitive shut-off element shuts off electric power to the corresponding one of the two heating members when a temperature of a surface of the corresponding one of the two heating members exceeds a certain value. The second heat-sensitive shut-off element shuts off electric power to the corresponding one of the two heating members when a temperature of a surface of the second one of the two heating members exceeds a certain value.
摘要:
A needle disposal apparatus for melting a needle to be disposed of by passage of electrical current through it, has a guide member having an inlet which permits the needle to be inserted; an upper electrode roller, to which a first voltage is applied, the inserted needle making contact with an outer surface of the upper electrode roller; a lower electrode roller to which a second voltage is applied, the inserted needle making contact with an outer surface of the lower electrode roller; and a drive mechanism which rotates the electrode rollers in each direction so that the inserted needle is drawn between the electrode rollers; wherein the electrode rollers are disposed so that a part of the lower electrode roller is hidden behind the upper electrode roller when viewed from the inlet in a direction of insertion of the needle.