Abstract: An ink jet print head comprises a substrate formed with a heating resistor, an ink path defining member for defining an ink supply path, and a orifice plate, and in the orifice plate, there is formed an ink outlet at the position opposing the heating resistor. Further, a heating zone surrounding the heating resistor is formed at the position corresponding to the heating resistor of the ink supply path. The channel resistance of the ink supply path is set so that a relationship is established between a quantity q of the discharged ink drop, a sectional area A of the ink outlet, and a maximal projection h that a meniscus of the ink has when it projects from the ink outlet after it has restored the exit level from a retreat position it had after the drop of the ink had been discharged, such that 0<h<0.3 q/A. Consequently, there is obtained a high-speed printing of high quality without dispersion.

Abstract: A toner density sensor, including a light emitting element and a light receiving element, detects toner density even for a liquid developer having a low transmission factor. The toner density sensor includes a liquid developer tank for retaining liquid developer, a diluting liquid tank for retaining diluting liquid which is a base material of the liquid developer, and a mixing chamber connected to the tanks through two separate valve/pump assemblies which are opened and closed by a controller. A circulation passage is formed in the mixing chamber and has disposed therein a third pump and a transparent cell element. A quantity of light transmitted by the light emitting element and passing through liquid developer in the transparent cell element is measured by the light receiving element on an opposite side of the transparent cell element.

Abstract: An electrostatic ink jet recording head of a drop-on-demand type has a head body defining an ink chamber for receiving liquid ink containing charged toner particles, a set of electrodes for migrating the liquid ink by electrophoresis and ejecting the liquid ink from an ejecting slit of the ink chamber, and an ink reservoir, disposed above the ink chamber, for circulating the liquid ink by gravity between the ink reservoir and the ink chamber. A flow resistance against the liquid ink in the flow path from the outlet port of the ink chamber to the ink reservoir is smaller than a meniscus force generated by meniscuses formed at the ejecting slit to effectively eject the liquid ink without a pump and without an ink leakage.

Abstract: A coaxial connector includes an upper insulating case provided with columnar ribs in the four corners thereof. These ribs are provided to position a fixed terminal and a movable terminal. The tops of the ribs are arranged so that the fixed terminal is easily guided. Half-circular concavities are formed on both of the sides of the fixed terminal. The concavities are fitted onto the ribs of the upper insulating case, so that the fixed terminal can be incorporated into the upper insulating case with a high positional accuracy. Thereafter, the ribs are thermally deformed into a dome shape by a welder, so that the fixed terminal is fixed to the upper insulating case.

Abstract: Power lines includes three or more conductors for transmitting alternating currents wherein said conductors are arranged in one combination of the conductor arrangement in which the sum of phase differences between the currents flowing through adjacent conductors is maximum and if there exist a plurality of such combinations, said one combination is selected in which the value of the smallest one of the phase difference between the currents flowing through every adjacent conductors is largest. With this arrangement, the power loss is reduced.

Abstract: An inkjet device ensuring reliable and stable ink ejection is disclosed. A plurality of ejection electrodes are arranged in a housing having an ink chamber containing ink including toner particles and a gate electrode plate is placed at a predetermined distance from the ejection electrodes. The gate electrode plate has a slit formed such that the ejection electrodes are directed to the slit and an ink drain coupled to the slit for draining ink from the slit.

Abstract: A movable terminal and a coaxial connector have greatly improved durability and have outstanding contact/connection reliability, and are included in a communication apparatus. A coaxial connector includes a two-split synthetic resin case having a lower insulating case and an upper insulating case, a metal fixed terminal, a movable terminal, and an external terminal. The movable terminal having a spring movable function includes a movable contact portion with which the fixed terminal makes contact, a fixed portion fit in the upper and lower insulating cases, and a lead portion bent in an L-shape. The movable contact portion has a frame-shaped portion, a spring movable portion upwardly curved in an arcuate shape, and a contact portion provided at the approximate center of the spring movable portion.

Abstract: An ink jet print head comprises a substrate formed with a heating resistor, an ink path defining member for defining an ink supply path, and a orifice plate, and in the orifice plate, there is formed an ink outlet at the position opposing the heating resistor. Further, a heating zone surrounding the heating resistor is formed at the position corresponding to the heating resistor of the ink supply path. The channel resistance of the ink supply path is set so that a relationship is established between a quantity q of the discharged ink drop, a sectional area A of the ink outlet, and a maximal projection h that a meniscus of the ink has when it projects from the ink outlet after it has restored the exit level from a retreat position it had after the drop of the ink had been discharged, such that 0<h<0.3 q/A. Consequently, there is obtained a high-speed printing of high quality without dispersion.

Abstract: An ink jet print head comprises a substrate formed with a heating resistor, an ink path defining member for defining an ink supply path, and a orifice plate, and in the orifice plate, there is formed an ink outlet at the position opposing the heating resistor. Further, a heating zone surrounding the heating resistor is formed at the position corresponding to the heating resistor of the ink supply path. The channel resistance of the ink supply path is set so that a relationship is established between a quantity q of the discharged ink drop, a sectional area A of the ink outlet, and a maximal projection h that a meniscus of the ink has when it projects from the ink outlet after it has restored the exit level from a retreat position it had after the drop of the ink had been discharged, such that 0<h<0.3 q/A. Consequently, there is obtained a high-speed printing of high quality without dispersion.

Abstract: An inkjet device having a plurality of ejection electrodes includes a gate electrode plate having a plurality of gate electrodes therein corresponding to the ejection electrodes, respectively. A voltage difference between the ejection electrode and the gate electrode is generated and is changed between a first value and a second value depending on an input signal. The first value is equal to or greater than a threshold value and the second value is smaller than the threshold value. The threshold value is a minimum value which can cause ejection of particulate matter from each ejection electrode.

Abstract: An electrostatic ink jet printing head comprises printing electrodes formed on the base film of a substrate. The printing electrodes have insulating coating films which coat the printing electrodes, respectively. Each of the printing electrodes has a main electrode portion formed on the base film and a protruding electrode portion which protrudes from the base film. A covering member covers the main electrode portion. The covering member has an internal surface defining, in cooperation with the main electrode portions and the base film, a ink receiving space which receives ink containing toner particles.

Abstract: An electrostatic ink-jet recording device which provides stable printing by preventing too much charged toner from gathering around an ink discharge aperture even if the charged toner has not been discharged for a long time. If the charged toner is not to be discharged, the potential difference between the electrophoretic electrode and the discharge electrode is so controlled as to suppress electrophoretic movement of the charged toner toward the ink discharging aperture, or the potential difference is made zero. If the charged toner is to be discharged, the voltage applied to the discharge electrode is kept lower than the voltage applied to the electrophoretic electrode for a predetermined period of time before discharging a jet of the charged toner.

Abstract: An inkjet recording apparatus includes an insulating support member having a major surface on which a plurality of ejection electrodes are formed with each of the ejection electrodes protruding from an ejection end of the insulating support member. Each of the ejection electrodes is coated with an insulating material. Further, a cover member is provided to cover the insulating support member to form ink chambers between them and an opening at an ejection end of the cover member. The ejection portion of each ejection electrode protrudes from the ejection end of the cover member through the opening. The ink is supplied from one ink chamber to the ejection electrodes and flows into the other ink chamber through the ejection electrodes.

Abstract: An electrostatic ink jet recorder of the type controlling charged toner particles contained in ink by using electrophoresis is disclosed. The recorder achieves a miniature and cost-effective configuration by reducing the number of drivers for driving ejection electrodes and auxiliary electrodes. The same amount of toner particles is ejected from all of ejection electrodes despite a scatter in the ejection electrode and a scatter in the position of the ejection electrode relative to auxiliary electrodes and a counter electrode.

Abstract: An inkjet recording apparatus includes a plurality of ejection electrodes and a counter electrode which are controlled at predetermined intervals such that a first voltage pulse is applied to a selected ejection electrode depending on input data and a second voltage pulse is applied to the counter electrode in synchronization with the first voltage pulse. The first and second voltage pulses produce a voltage difference between the selected ejection electrode and the second electrode, wherein the voltage difference is not smaller than a predetermined threshold voltage which is a minimum value which causes ejection of particulate matter from the selected ejection electrode.

Abstract: An electrostatic ink jet recording device includes a recording head having an ink chamber receiving therein liquid ink containing electrified toner particles and a plurality of recording electrodes for ejecting the toner particles from the liquid ink. Each of the recording electrodes is applied with a bias pulse train when the recording head resides in a printing area and a non-printing area, and a selected group of the recording electrodes are applied with a constant recording signal for ejection of toner particles. Undesirable ejection of the toner particles in the non-printing area is avoided by the application of the bias pulse train.

Abstract: Light of a light emitting portion is received by a total of two light receiving portions disposed opposite to each other through a record medium. The surface condition of the record medium is detected corresponding to the amount of light reflected and the amount of light transmitted so as to determine whether the record medium placed is plain paper, coated paper, OHP film, or the like. By controlling the number of heating elements of a heater or turning on/off the heater, an optimum fixing condition is accomplished.

Abstract: An ink jet recording head comprises a plurality of electrophoretic electrodes corresponding to a plurality of ejecting electrodes, and a pair of stirring electrodes disposed at both ends of the row of the ejecting electrodes. The stirring of the colored particles by the stirring electrodes prevents block of an ink jet slit by the concentrated colored particles, whereas individual control of the electrophoretic electrodes prevents undesirable ink ejection from non-specified ejecting electrode.

Abstract: The quantity of toner particles in an ink is detected by a toner quantity detector. The quantity of toner particles is integrated for a predetermined time period by a controlling portion. The integrated value is compared with a reference value. When the integrated value is smaller than the reference value, a value is opened for a predetermined time period so as to supply a toner in a toner replenisher to an ink tank. Thus, a predetermined quantity of the toner is replenished to the ink tank. After the toner has been replenished, when the integrated value does not become larger than the reference value, a valve is opened for a predetermined time period under the control of the controlling portion so as to replenish a charge control agent from a charge control agent replenisher to the ink tank.

Abstract: An ink jet print head comprises a substrate formed with a heating resistor, an ink path defining member for defining an ink supply path, and an orifice plate, and in the orifice plate, there is formed an ink outlet at the position opposing the heating resistor. Further, a heating zone surrounding the heating resistor is formed at the position corresponding to the heating resistor of the ink supply path. The channel resistance of the ink supply path is set so that a relationship is established between a quantity q of the discharged ink drop, a sectional area A of the ink outlet, and a maximal projection h that a meniscus of the ink has when it projects from the ink outlet after it has restored the exit level from a retreat position it had after the drop of the ink had been discharged such that 0<h<0.3q/A 0<h<0.25q/A. Consequently, there is obtained a high-speed printing of high quality without dispersion.