Abstract: A sheet feed mechanism for feeding sheets one at a time, comprising a hopper loaded with a stack of sheets, a feed roller disposed near the outlet of the hopper, and a resilient tongue held in resilient contact with the central section of the feed roller. The central section of the feed roller is provided with an alternate circumferential arrangement of low friction portions and high friction portions. The friction coefficients between the sheet and the low friction portions is smaller than that between the sheet and the tongue, and the friction coefficient between the sheet and the high friction portions is greater than that between the sheet and the tongue.

Abstract: A color image reproduction apparatus includes a light source, a filter, a sensor means, an ink ribbon, a printer including a printer head and a printer drive, a feeder and a controller. The light source illuminates spots on the color original and light reflected therefrom is filtered by one of three aligned segments of the filter which are connected end-to-end in an alignment direction which three segments respectively filter different first, second and third portions of the visual spectrum. The sensor is disposed behind the filter and senses the light filtered by one of the three different filter segments when the one of the segments is disposed in front of sensor. The sensor outputs an intensity signal indicating the intensity of the sensed light. The ink ribbon is fixed in relation to the filter and has three different color ink layers which are attached to each other end-to-end in the same alignment direction as are the light filter segments.

Abstract: An electronic print board system includes a drawing medium on which images can be erasably written manually, an external input device for supplying external image data, a writer device for erasably writing images on the drawing medium corresponding to the external image data received from the external input device, a device for reading images on the drawing medium and producing output image data corresponding thereto, a device for printing images on a recording medium corresponding to the output image data from the reader device, and a control device for selectively causing the writer device to write images on the drawing medium corresponding to the external image data received from the external input device and for selectively causing the printer device to print images on the recording medium corresponding to the output image data received from the reader device.

Abstract: A cleaning device for a photosensitive drum a rotatable cylindrical device including a permanent magnet, for carrying toner wiped off the surface of the photosensitive drum, a scraper for making contact with the peripheral surface of the rotatable cylindrical device, and a rotary blade formed of a magnetic material. The rotary blade scrapes off the toner blocked by the scraper upon rotation of the rotary blade so as to force the toner to fall off for toner recovery.

Abstract: A developing roll is composed of a hollow nonmagnetic sleeve and a permanent magnet disposed therein and having a plurality of poles, the sleeve and the permanent magnet being independently rotatable in the same direction. The hollow nonmagnetic sleeve is rotatable at a constant speed. The permanent magnet is rotatable at varying speeds dependent on a signal indicative of a count value from a printing density counter means for supplying a developer from a developer tank. The printing density counter means successively counts print data to be developed.

Abstract: This invention provides an ink mist type high speed printer in which an aperture board is provided between a first electrode and a second electrode across which a high voltage is applied. The aperture board is adapted to selectively control passage of ions generated from the second electrode, and a stream of ink mist is passed between said aperture board and first electrode so that the ions which have passed said aperture board will electrically charge the ink mist particles selectively to let the electrically charged ink mist particles deposit on a recording paper placed between the ink mist and first electrode to thereby print the desired dot matrix characters. This invention also features provision of electrostatic shields placed between said first electrode and ink mist stream and at places outside of the desired printing space to guard the aperture board against deposition of ink mist particles.

Abstract: A high speed printer in which ions produced between the high voltage impressed electrodes are modulated and then passed through an ink mist to electrically charge the ink particles to thereby print desired letters, figures, signs, etc., on a printing paper, characterized in that an electronegative gas containing a fluorine component and not containing any chlorine component is flown into the aperture board to prevent are discharge that would otherwise take place between the anode and aperture board.

Abstract: This invention provides an ink mist type high speed printer comprising a first electrode and a second electrode between which a high voltage is applied, and an aperture board disposed between the first and second electrodes and adapted to selectively control passage of the ions generated from the second electrode, wherein a stream of ink mist is passed between the aperture board and first electrode so that the ions which have passed the aperture board will selectively charge the ink mist particles to let the charged ink mist particles deposit on a recording paper placed between the ink mist and first electrode to thereby print a desired dot matrix character.

Abstract: A high speed printer in which the ions produced between the high voltage impressed electrodes are modulated by an aperture board and then passed through an ink mist so as to electrically charge the ink particles whereby to print the desired letters, figures, signs, etc., on a printing paper, characterized in that a heating element is provided in the aperture board for lowering the relative humidity in said aperture board.

Abstract: A high speed printing apparatus in which ions produced between electrodes receiving a high voltage are passed through an ink mist so that they are deposited with the ink particles to perform printing with such ion-loaded ink, characterized in that the ink mist produced in a mist tank is once stored in a reservoir tank and then fed to the printing section.

Abstract: A conductive shield board for protecting an aperture board from discharge is mounted between a positive electrode and said aperture board in an ink mist type high speed printer.The ink mist type printer operates on the principle that an ion stream modulated by an aperture board according to the pattern of the character to be printed, charges the ink mist, which is then attracted by an electric field, to the surface of the paper. However, a high potential on a positive electrode for generating said ion stream sometimes causes an undesirable discharge between the positive electrode and the aperture board.In order to avoid said undesirable discharge, a conductive shield board is inserted between the positive electrode and the aperture board.

Abstract: A high speed printer for printing desired letters, figures, signs, etc., on a paper by depositing ink particles on the paper after properly controlling ink droplets or selectively controlling corpuscles, characterized in that at least one ink mist passage is provided at a location closely adjacent to the surface of ink solution. An air feed port also is provided for introducing air into said ink mist passage after the air passes the ink mist source or its vicinity so that the produced ink mist will flow into said ink mist passage without forming any small convection.

Abstract: A conductive protection board for protecting an aperture board from dust is mounted in an ink mist type high speed printer. The ink mist type printer operates on the principle that an ion stream modulated by an aperture board according to the pattern of the character to be printed, charges the ink mist, which is then attracted by an electric field to the surface of the paper. If an aperture of said aperture board is obstructed, a portion of the printed character will not be evident. In order to avoid the obstruction of an aperture the conductive protection board which has a plurality of apertures, each of which corresponds to each aperture of the aperture board, is placed very close to said aperture board.

Abstract: In a high speed printing apparatus in which ions produced between electrodes, to which is applied a high voltage, are passed through mists of ink, and particles of ink adhere to the ions to cause the printing operation to be conducted, said apparatus is characterized in that the air is supplied in such a way that only the desired printing width is left between the recording paper and the ink mists.