Tokyo Electric Co.

Yoshihiro Torisawa

Mitsuharu Endo

Masashi Shimosato

Tetsuroh Nakayama

Ayumu Makino

Shigeru Okuno

Takeyoshi Tsuge

Takafumi Fukushima

Tsutomu Kimura, Deceased

Hisashi Nishikawa

Tutomu Kimura

In the image forming apparatus of the present invention, printing stations are provided in positions opposed to an endless paper conveying belt, and an electric charger is disposed close to a conveyance roller and on a downstream side of the conveyance roller with respect to a conveyance direction, which conveyance roller is disposed in a conveyance start position of the paper conveying belt, to maintain the surface potential of each recording paper in good condition, whereby it is made possible to prevent the deterioration of the image quality, diminish the power consumption and attain a reduction in size of the apparatus.

Electrophotographic image forming apparatus having multiple printing

A dot printer wherein a film of magnetic ink is formed in a slit shaped between a pair of magnetic poles, and needles piercing through the ink film thus formed are driven to deposit the magnetic ink on a recording paper so as to print dots thereon. The tips of the needles in an undriven state are positioned in the ink film proximately to one surface thereof adjacent to the recording paper, so that an adequate amount of the magnetic ink is deposited on the paper to eventually attain clear printing.

Dot printer

An ink-dot printer comprises a recording paper, at least one needle disposed in one side the recording paper and movable between a rest position remote from the recording paper and a projected position close to the recording paper, a driving mechanism for moving the needle between the rest position and the projected position, a driving control unit electrically connected to the driving mechanism so as to supply a driving control signal for controlling the movement of the needle to the driving mechanism, an ink supply mechanism adapted to supply ink to the distal end portion of the needle on the recording sheet side so that the ink attaches to the distal end portion when the needle is located in the rest position, an electrode disposed in another side of the recording paper and facing the distal end portion of the needle, and voltage control unit for applying between the needle and the electrode an ink flying voltage with respect to the supply of the driving control signal from the driving control unit to the driving mechanism the ink flying voltage generating between the needle and the electrode an ink flying electric field of an intensity such that the ink is drawn from the distal end portion of the needle to the recording paper to form an ink dot on the recording paper as the needle closes to the electrode than in the rest position.

Ink-dot printer

An ink dot printer comprises a recording sheet, at least one needle made of an electrically conductive material and located in one side of the recording sheet so as to move between a normal position remote from the recording sheet and a projected position close to the recording sheet, a drive mechanism for displacing the needle between the normal position and the projected position, an ink supply mechanism for supplying and attaching ink to the tip of the needle which faces the recording paper when the needle is in the normal position, an electrode disposed on another side of the recording mechanism and facing the tip of the needle, and an electric field generating mechanism for generating, between the electrode and needle, an electric field of such intensity as to cause ink to fly from the tip of the needle, when the needle is closer to the recording sheet than the normal position, toward the recording sheet to thereby form an ink dot on the recording sheet.

Ink dot printer

An ink-dot printer comprises a pair of slit forming members arranged to define a slit therebetween, an ink tank for storing ink in which the slit is immersed, a recording sheet opposed to the slit, a needle movable between a rest position and a projected position, a driving mechanism for moving the needle between the two positions, and an ink attracting unit for generating a magnetic or electric field in the slit, thereby attracting the ink from the ink tank into the slit to cause the ink to attach to the distal end portion of the needle located in the rest position, the ink attracting unit being adapted to generate an ink attracting magnetic or electric force of a necessary intensity for the ink to be attracted from the ink tank into the slit at the time of ink attraction, and to generate an ink holding magnetic or electric field of a minimum necessary intensity for a predetermined amount of ink to be held in the slit after the predetermined amount of ink is attracted into the slit, wherein the ink attaching to the distal end portion at the rest position is moved to the recording sheet to form an ink dot thereon as the needle moves to approach the recording sheet in a projected position.

An ink dot printer comprising an opposite electrode, a carriage capable of reciprocating along the opposite electrode, a printing head mounted on the carriage, recording electrodes arranged within the printing head so that the tips thereof can be exposed through openings formed in a wall of the printing head opposite the opposite electrode, and a cap supported moveably on either the carriage or the printing head so as to close or open the openings of the printing head. When the ink dot printer is not in printing operation, the cap is closed to cover up the tips of the recording electrodes to prevent the drying of the tips of the recording electrode due to the evaporation of the ink so that the recording electrodes are always in good condition for stable printing operation.

An ink dot printer includes an ink tank for storing magnetic ink, a pair of magnetic pole plates arranged opposite to each other to form a slit, one end of the pair of plates being immersed in the magnetic ink in the ink tank. An electromagnet magnetizes the paired magnetic pole plates to introduce the magnetic ink in the ink tank into the slit to form a magnetic ink film therein, and a plurality of needles arranged adjacent to one another in the longitudinal direction of the slit are each freely movable in the longitudinal direction of the needle between a first position where its one end portion is immersed in the magnetic ink film in the slit between the paired magnetic pole plates and a second position where its one end portion is projected from the magnetic ink film in the slit. An electromagnet selectively drives the needles to move them from the first to the second position, and a variable resistance controls the strength of magnetic force generated by the electromagnet by controlling the voltage supplied to the electromagnet. Magnetic ink, which has been stuck to the one ends of the needles at the first position, is forced onto a recording paper at the second position to form dots of magnetic ink of controlled density. By the gathering of the dots, symbols such as characters and numerals are printed.

Magnetic ink dot printer with means for controlling print density

An ink-dot printer comprises a magnetic ink storage tank storing magnetic ink, a pair of pole plates facing each other so as to define a slit one end portion of which is contacted with the magnetic ink supplied from the magnetic ink storage tank, an electromagnet for magnetizing the pole plates, thereby feeding the magnetic ink from the magnetic ink storage tank into the slit to form a magnetic ink curtain in the slit, and a plurality of needles arranged adjacent to one another along the longitudinal direction of the slit and adapted selectively to move in the longitudinal direction thereof between a first position where one end portion of each needle is immersed in the magnetic ink curtain in the slit and a second position where the one end portion is projected from the magnetic ink curtain in the slit, the cross-sectional area of the one end portion of each needle being made to narrower than that of the remaining portion of the needle so that the distance between the one end portions of any two adjacent needles is widened to prevent the magnetic ink from being retained between the portions adjacent to the end faces of the one end portions by surface tension when the two needles are simultaneously located in the second position.

Ink-dot printer with magnetic ink attracting and retention preventing

An ink dot printer comprises: an ink tank storing magnetic ink; a pair of magnetic pole plates arranged opposite to each other to form a slit whose one end is immersed in the magnetic ink in the ink tank; an electromagnet magnetizing the paired magnetic pole plates to introduce the magnetic ink in the ink tank into the slit to form a magnetic ink film therein; a plurality of needles arranged adjacent to one another along the longitudinal direction of the slit where each is freely movable in its longitudinal direction between a first position where its one end portion is immersed in the magnetic ink film in the slit and a second position where its one end portion is projected from the magnetic ink film in the slit; electromagnets for selectively driving the needles to move from the first position to the second position; and stoppers which collide with the needles in the course of their moving from the first position to stop the needles at the second position; wherein the driving force produced in the electromagnets is so set that the magnetic ink is flied from the end faces of the one end portions of the needles onto a recording paper thanks to an inertia of the magnetic ink on the end faces of the one end portions of the needles which is caused by the collision of the needles with the stoppers.

Growing community of inventors

Mishima, Japan

Yoshihiro Torisawa