Abstract: Characteristics of a droplet ejection apparatus are change depending on the shape or cone angle of the main ink ejection chamber of the apparatus, or on the diameter of the ejection aperture of main ink ejection chamber. Accordingly, operation of the droplet ejection apparatus varies with the shape, angle, or diameter of main ink ejection chamber. The shape of the aperture according to the present invention is circular or regular polygonal so that surface waves are synthesized at the central portion of the ejection aperture. Moreover, the cone angle of the main chamber is set to 65° or less from the plane vertical to the droplet ejecting direction and the diameter of the ejection aperture is set to a value 1.25 times or more larger than a desired droplet diameter.

Abstract: An ink-jet recording head is capable of always performing high-speed recording with high image quality in a stable manner independently of a change in the environmental temperature while an apparatus is in operation. The configurations of a nozzle 7, an ink supply aperture 6, and a pressure generating chamber 2 are set so that an inertance mT and an acoustic resistance rT (the values substantially at a temperature of 20° C.) of the nozzle 7, the ink supply aperture 6, and the pressure generating chamber 2 in an ink-filled state satisfy expressions (1) and (2), respectively: 0<mT<1.9×108[kg/m4]  (1) 4.0×1012<rT<11.

Abstract: An inkjet recording head allowing a high driving efficiency and preventing a variation in the driving efficiency is disclosed. An piezoelectric actuator is provided for each ink nozzle and has a driving section disposed in an area of an ink pressure chamber, an electrode pad section, and at least one bridge section connecting the driving section and the electrode pad section. The pressure chamber has a plane shape having an aspect ratio approximately equal to 1, and the bridge section has a width of a connection area to the driving section set smaller than a width of a connection side of the driving section.

Abstract: In an image recording device which records an image on a recording medium responsive to a desired gradation in each pixel and which includes a recording head for jetting an ink droplet having a diameter at a timing therefrom, the diameter of the ink droplet is modulated in response to the desired gradation in each pixel while the timing is modulated dependent on the modulated diameter. Thus, a position of impact of the ink droplet is not deviated, so that quality of image is not deteriorated.

Abstract: Characteristics of a droplet ejection apparatus are changed depending on the shape or cone angle of the main chamber of the apparatus or the diameter of the ejection aperture of the apparatus and thus, the apparatus may not be normally operated depending on the setting of the shape, angle, or diameter.

Abstract: In order to reduce a manufacturing cost of an ink jet type recording head by simplifying a structure of the ink jet type recording head and reducing the number of manufacturing steps thereof, to provide a capacity of an ink pool without increasing a size thereof, to make the freedom of nozzle layout high and to make the freedom of design by reducing a restriction on position and number of ink supply ports, the ink pool to which ink is supplied is formed in a rear surface of a nozzle plate having a front surface formed with a plurality of nozzles and an ink chamber plate is attached to the rear surface of the nozzle plate through discrete partition walls each defining a discrete space communicating with different one of the nozzles.

Abstract: In an image recording device which records an image on a recording medium responsive to a desired gradation in each pixel and which includes a recording head for jetting an ink droplet having a diameter at a speed therefrom, the diameter of the ink droplet is modulated in response to the desired gradation in each pixel while the speed is modulated dependent on the modulated diameter. Thus, a position of impact of the ink droplet is not deviated, so that quality of image is not deteriorated.

Abstract: A cleaning device includes a removing portion and a heater. The removing portion removes a toner held by an electrostatic force on a first surface of a latent image charge holding member. The latent image charge holding member includes a pyroelectric layer having a first surface on which the toner is deposited. The heater heats the pyroelectric layer to reduce the electrostatic force attracting the toner to the first surface of the pyroelectric layer, and the removing portion thereby removes the toner from the latent image charge holding member. In another embodiment of the cleaning device, the heater is incorporated in the removing portion which is a blade. In still another embodiment the cleaning device includes a heater and an ultrasonic vibrator is used as the removing portion.

Abstract: An image printing device includes a latent image charge keeping medium including a pyroelectric layer, a thermal head for selectively heating the charge keeping medium according to a signal, and an electrically conductive film disposed to be brought into contact with or to be in the vicinity of a surface of the pyroelectric layer of the medium for being heated by the thermal head, thereby neutralizing charge appearing on the medium due to pyroelectric effect. The device further includes a developer for visualizing with a charged coloring medium an electrostatic latent image formed on the medium, a transfer roller for transferring the developed image onto a sheet of printing paper, and a fixing device for fixing the transferred image on the printing sheet. The conductive layer is applied with a bias voltage from a power source such that a strong absorbing force acts upon charge, thereby efficiently neutralizing the charge.