Abstract: An actuator unit is driven with a voltage pulse supplied from a driver IC. The actuator unit can take two states of a first state wherein the volume of a pressure chamber is V1, and a second state wherein the volume of the pressure chamber is V2 larger than V1. A state of the actuator unit changes from the first state to the second state and then to the first state again so that ink is ejected through a nozzle connected to one end of the pressure chamber. A pulse width Tw of the voltage pulse to be supplied to the actuator unit is shorter than a pulse width Tmax at which a maximum ejection speed of ink ejected from the nozzle is obtained. Thus, with simplifying a waveform of the voltage pulse, two of large and small ink droplets can be successively ejected in the order of the large and small ink droplets.

Abstract: An ink-jet head includes a plurality of nozzles that eject ink, a first flat plate layer including at least one flat plate formed with an array of pressure chambers each communicating with a corresponding one of the nozzles, a second flat plate layer including at least one flat plate formed with a common ink chamber having a shape elongated in a direction of the array of the pressure chambers, an ink flow passage that communicates at one end with a corresponding one of the pressure chambers and at the other end with the common ink chamber, an ink supply passage connecting the common ink chamber and an ink supply source, a flat plate member in a shape of a thin film disposed between the first flat plate layer and the second flat plate layer, a filter formed at the flat plate member for filtering the ink, and a damper chamber formed by a flat plate fixed on the flat plate member on a side thereof opposed to the common ink chamber.

Abstract: An ink-jet head includes a plurality of nozzles that eject ink, a first flat plate layer including at least one flat plate formed with an array of pressure chambers each communicating with a corresponding one of the nozzles, a second flat plate layer including at least one flat plate formed with a common ink chamber having a shape elongated in a direction of the array of the pressure chambers, an ink flow passage that communicates at one end with a corresponding one of the pressure chambers and at the other end with the common ink chamber, an ink supply passage connecting the common ink chamber and an ink supply source, a flat plate member in a shape of a thin film disposed between the first flat plate layer and the second flat plate layer, a filter formed at the flat plate member for filtering the ink, and a damper chamber formed by a flat plate fixed on the flat plate member on a side thereof opposed to the common ink chamber.

Abstract: The intermediate medium is an endless belt wound around and spans intermediate medium transport rollers and a transfer roller. Ink jet heads are disposed outside of the loop, their nozzles facing to the intermediate medium. A phase-changeable ink is ejected from the ink jet heads onto the intermediate medium to form an intermediate image. The intermediate image is pressed against a recording medium and transferred onto the recording medium whose surface to be recorded is directly heated in advance, and a final image is obtained. In this way, double-sided printing can be performed without any damage on the printed side.

Abstract: The invention relates to a method for setting a tolerance of each standard value, which is a factor in determination of ink droplets landing accuracy, to an ink jet printer that is set up using the method, by implementing a sensory test using printed results of an ink jet printer. With the tolerances set by the method, banding can be effectively obscured without significantly improving the mechanical precision of the ink jet printer. Particularly, when A1 is a deviation of a sheet feeding amount in the sub-scanning direction obtained by a dot line length of an average value of the sheet feeding amount in the sub-scanning direction from an ideal value, B1 is a maximum value of a deviation in the sub-scanning direction between the same color dots, and C1 is a maximum value of a deviation in the main scanning direction between the same color dots, it is set such that a value of tolerances of A1, B1, and C1 is A1≦B1≦C1.

Abstract: An image forming device including a plurality of image forming units each for forming an image on an intermediate transfer body using one of different colored inks. Different colored images are selectively formed in an overlapping relation on the intermediate transfer body, thereby forming a multicolor image thereon. Each different colored image is formed by a thermal transfer operation in which ink on an ink holding member is heated, melted, and then transferred directly onto the intermediate transfer body or onto an existing ink image on the intermediate transfer body. Heat to be supplied to the ink to be transferred onto the existing ink image is insufficient to melt ink in the existing ink image.

Abstract: The image composing apparatus of the invention includes an ink medium, a halogen heater for preparatorily heating the ink medium, and a thermal head which heats the ink medium and transfers the heat sublimation ink onto the recording medium. The ink medium has an ink carrier made from a resin on which a heat sublimation ink is dispersed and which is formed on the outer perimeter of a cylindrical axle on which a heat resistant resin layer of polyimid, or similar material, is formed on the surface. The ink maintaining unit temporarily maintains the heat sublimation ink which has sublimed by a preparatory heating using from the halogen heater established inside the axle to move from the ink carrier to the surface layer.

Abstract: A color image output apparatus having a plurality of single color image forming units for different colors arrayed in-line. Each single color image forming unit includes a toner box, a photosensitive drum and a transfer roller, and provides a position adjusting unit for moving its image transfer portion in a direction toward and away from or normal to a running direction of an intermediate image transfer belt. Each position adjusting unit includes a motor fixed to the toner box, a thread fixed to an output shaft of the motor, an arm fixed to a main frame and engageable with the thread. Each rotation of each motor provides independent movement of each toner box of each single color image forming unit. This movement provides inclination of the intermediate image transfer belt between neighboring image transfer portions.

Abstract: A developing device for use with an image forming apparatus that is capable of reliably preventing the entry of large particles of developing agent between a layer thickness limiting member and a developing agent carrier. The developing device includes an image carrier and a developing agent carrier that conveys a developing agent to the vicinity of the image carrier. The developing agent is conveyed to the vicinity of the image carrier. A layer thickness limiting member limits a thickness of a layer of the developing agent. The layer thickness limiting member includes a columnar member having a ridge line closely parallel to the surface of the developing agent carrier. The ridge line limits the thickness of the developing agent layer.

Abstract: In an image forming device, a hot melt ink is preliminarily heated by a heater, the melted ink is retained in an ink retaining roller made of a porous material and having apertures formed in the radial direction, and then melted under heating by a thermal head and transferred on a recording medium. The ink supply device of the image forming device can use inks efficiently with no waste and thereby reduce the running cost.

Abstract: The rotational shaft 22 is provided with a pair of permanent magnets 31a and 31b, at its opposite ends. The bearing device 30 for the light scanning apparatus includes: a pair of electromagnets 32a and 32b; and a pair of voltage control circuits 33a and 33b. The electromagnet 32a is constructed from an iron core 321a provided with a coil 322a. Similarly, the electromagnet 32b is constructed from an iron core 321b provided with a coil 322b. When the rotational number increases to exceed a predetermined rotational number, the control signal generating circuit 53 switches the electric voltage applied through each of the coils 322a and 322b so as to switch the bearing stiffness of the bearing device. As a result, the resonant frequencies of the conical and cylindrical modes become much lower than the present actual rotational number .omega.0 of the rotational shaft. Accordingly, it is possible to prevent the rotational shaft from exhibiting any of the conical and cylindrical mode resonant actions.

Abstract: In a preferred mode of a light scanning device, a reflection mirror is designed in an inverted cup-shaped form and has a hexahedral means portion at the outer side thereof and a bearing at the bottom portion thereof. The bearing includes a pivot receiving portion and a damping portion. The pivot is erectly provided on the rotational center axis of the reflection mirror such that it is not rotated. The upper end of the pivot rotatably supports the pivot receiving portion, so that the reflection mirror is rotatably supported by the housing. A motor for rotating the reflection mirror is disposed at the inner side of the reflection mirror. However, other structures are possible that result in a resonance rotating number that is approximately one-third of the operational rotating number.

Abstract: In an image forming apparatus for forming a toner image on image recording medium, an aperture electrode is provided for modulating electrically charged toner particles to be applied on image recording medium to thereby form a toner image on the image recording medium. An oscillating device is provided on the aperture electrode for causing the aperture electrode to vibrate. The image forming apparatus is further provided with modulating device for modulating vibration properties of the vibration caused by the oscillating device. The modulating device modulates amplitude or frequency of the vibration.

Abstract: An image recording apparatus comprises an aperture electrode for modulating and regulating a flow of charged toner particles, and a vibrating device for vibrating the aperture electrode. The vibration generated by the vibrating device is a progressive wave transmitted in the aperture electrode. Since all of the apertures of the aperture electrode efficiently vibrate at a sufficient amplitude, adhesion of the toner particles to the aperture electrode is easily prevented.

Abstract: The control electrode unit including an insulative layer, a reference electrode on one surface of the insulative layer and at least one segment control electrode on an opposite surface of the insulative layer to which an image signal is applied. The control electrode unit has at least one row of apertures which pass through the segment control electrode, the insulative layer and the reference electrode, so that the charged particles pass through the apertures. The image recording apparatus includes a plurality of carrying units for carrying charged particles of different colors, and a moving unit for moving one of the carrying unit to the position disposed confronting the recording medium through the position confronting the medium through the control electrode unit. One of the carrying units is disposed at a position confronting the medium through the control electrode unit so that the charged particles carried by the carrying unit are carried toward the recording medium through the apertures.

Abstract: A toner jet recording apparatus having a particle-flow modulating electrode member having multiple apertures, a back electrode for supporting a recording medium interposed between the back electrode and the electrode member, and a control circuit for applying controlled electric signals to the electrode member and the back electrode, for causing flows of electrostatically charged toner particles through the selected apertures toward the back electrode. The apparatus is provided with an oscillating device for vibrating the electrode member, in a vibration mode in which an antinode is substantially aligned with a portion of the electrode member through which the apertures are formed. The oscillating device prevents plugging of the apertures with the particles.

Abstract: In the piezoelectric transducer, the elastic member vibrates, being excited by the first electromechanical transducing element. The impedance element on the second electromechanical transducing element is adjusted so that the vibration frequency and the resonance frequency of the elastic member should be almost the same. In the ultrasonic motor using the piezoelectric transducer, the vibration having the same frequency as that of the vibration of the elastic member is applied to the elastic member. This applied vibration has a direction differnt from that of the viration of the elastic member. The applied vibration and the vibration of the elastic member form approximate elliptical vibration, thereby rotating the rotor. The piezoelectric transducer of variable structure can control the resonance frequency in a wide range without electric power.

Abstract: An ultrasonic motor uses a piezoelectric transducer for effectively transmitting vibration energy and achieving high output. The piezoelectric transducer comprises elastic members, first and second piezoelectric elements, electrodes, and ceramic insulators inserted between the electrodes or between the electrodes and the elastic members. The first and second piezoelectric elements excite the vibration surfaces of the elastic members to vibrate in two modes and to generate approximate elliptical vibration by synthesizing the two vibration modes. The electrodes are provided for applying alternating current signals to the first and the second piezoelectric elements. The first and second piezoelectric elements are polarized such that they cause shear vibration in the same direction. The piezoelectric transducer is fixed in a motor case via a fixing plate. A rotor is provided in such a position as to contact the vibration surface of one of the elastic members.

Abstract: An ultrasonic motor includes an anisotropic layer disposed between an ultrasonic vibrator and a movable member. The anisotropic layer is made of a composite material including plural components. The ratio of the modulus of transverse elasticity of the layer to the modulus of longitudinal elasticity of the layer in the pressing direction of the movable member is smaller than the corresponding ratio of moduli for each of the components.

Abstract: An ultrasonic motor includes a retaining member which retains an ultrasonic vibrator. An electromechanical transducing element such as a piezoelectric element is attached on the retaining member. An impedance element is electrically connected with the electromechanical transducing element to form a closed circuit, and the antiresonance frequency of a parallel circuit formed of the reactance component of the electromechanical transducing element and the impedance element is substantially the same as the frequency of the ultrasonic vibration of the ultrasonic vibrator. This structure suppresses undesirable vibration in the retaining member and thus also avoids the undesirable propagation of vibration to external equipment.