Abstract: A color plotter capable of printing out alphanumeric characters and the like at a high speed in addition to color plots is disclosed. A print head assembly comprising ink ejection heads is partly allocated to multicolor plots and partly to single-color characters and controlled to selectively print out graphic data and character data on a sheet as desired. The print head assembly is mounted on a carriage. In a plotter mode, the carriage and sheet are driven each in a reciprocal movement in directions perpendicular to each other with the plot section of the print head assembly energized. In a printer mode, the character section of the print head assembly is energized in response to input pixel data while the carriage is stroking.

Abstract: An optical data pattern generation device scans an original document to generate an optical dot pattern corresponding to an image on the document. Optical dots are defined by portions at each of which an electrode array comprising minute electrodes and a minute phosphor member overlap each other. The individual electrodes are selectively energized to generate any desired optical dot pattern.

Abstract: A charged drop detection device for an ink jet printer is disclosed which detects a charged ink drop ejected from an ink jet head. Using a unique control signal conductor, the device is controlled in combination with a device for notifying drop charged/uncharged, phase search required/unrequired, charged drop deflection proper/improper, etc, by means of a light emitting diode and the like. The control signal conductor is connected to a microcomputer of a central control unit.

Abstract: An apparatus for processing an image into binary data is selectively operable with a fixed threshold level and a variable dither threshold level. When a threshold level commmand signal specifies the dither threshold level, a switchover means detects image data read from a character or like black-white image portion on an original document and specific part of a halftone image portion which is approximate in density level to black. The detection output forcibly changes the threshold level command signal from a dither threshold level command to a fixed threshold level command. The dither processing, therefore, occurs only for a minimum necessary halftone image portion in accordance with an image condition on the document.

Abstract: A fuel injection device for a diesel engine or the like confines the fuel injection pressure to a predetermined range. Fuel is fed under pressure from a fuel supply source to a high pressure chamber to develop a pressure therein. An injection nozzle is mounted on a nozzle holder and has a nozzle hole for injection fuel in response to the pressure in the high pressure chamber. The nozzle holder has thereinside a low pressure chamber which communicates to the outside. An injection rate control valve is mounted in the nozzle holder for delivering fuel to the low pressure chamber on the elevation of the fuel pressure communicated to the high pressure chamber beyond a predetermined value.

Abstract: An ink jet printing apparatus includes an ink condition detector for detecting a condition of ink. The ink condition detector produces outputs which represent a plurality of parameters of the ink. The parameters are the ink temperature, the ink pressure and the velocity of ink droplets in flight. A control device controls a charging device and/or a deflection device to compensate for a distortion in print position in accordance with an ink condition detected by the ink condition detector.

Abstract: An image density control method for an electrophotographic apparatus is disclosed which prepares a white pattern region and a black pattern region on a photoconductive element whose electrostatic latent images are far different from each other in potential. Values relating to image densities individually associated with the two pattern regions are sensed and, based on the sensed values, parameters relating to image processing which effect image density are controlled. When any of the sensed values does not lie in a predetermined range, it is suitably compensated.

Abstract: The velocity of flying charged ink drops is detected and the ink pressure is so controlled as to make the ink velocity coincide with a predetermined target velocity. A gutter for catching non-printing ink drops is made of a conductive material, while a charge detector circuit is connected to the gutter to generate a signal indicative of a potential change corresponding to impingement of a charged ink drop on the gutter, thereby detecting the flight of a charged ink drop. The pump pressure is varied in response to a difference between the actual and target velocities so that the ink pressure or velocity is adjusted in arithmetic progression reducing a time period required for the actual velocity to converge to the target.

Abstract: A facsimile relaying method transmits common picture information to a plurality of facsimile receivers designated by a facsimile transmitter, by once storing transmit picture information in a picture store of a relaying apparatus and then sequentially sending it out to the receivers. If a telephone number of any of the designated receivers does not include a toll number, a toll number included in the telephone number of the transmitter is added to the telephone number of the transmitter. If the toll number of the telephone number of the receiver is identical with the toll number of the relaying apparatus, the toll number is omitted from the telephone number of the receiver.

Abstract: A method and apparatus for automatically adjusting an operation time of a servosystem into a predetermined allowable range, either from the outside or from the inside. An average operation time of the servosystem is calculated and then an amount of level shift is calculated from the resulting average operation time. Based on the resulting level shift, the operation time of the servosystem is stepwisely shifted at a given time interval. After the shift, an average operation time of the servosystem is calculated again. This is repeated until the average operation time enters the allowable range.

Abstract: An injection timing control device for an internal combustion engine includes a connector plate constantly biased in a predetermined direction. A hydraulic actuator urges the connector plate in the other direction in response to a fluid pressure communicated thereto, thereby actuating an eccentric cam mechanism to vary a fuel injection timing. The line of action of the biasing force and that of the urging force opposite to the biasing force, each imparted to the connector plate, lie in a common plane which contains an axis of the hydraulic actuator, so that the connector plate is prevented from tilting and thereby effecting the operation of the cam mechanism.

Abstract: An ink jet printing apparatus is disclosed in which part of ink droplets ejected from a nozzle of an ink ejection head and unused for printing purpose is caught by a gutter and returned to an ink supply source through an ink circulation path to be reused. The ink is partly shunted for disposal while fresh ink is supplied to the ink supply source in proportion to the amount of ink disposal, thereby maintaining the ink viscosity always at a proper value. For the disposal of the ink, a three-way solenoid operated valve is opened periodically for a predetermined period of time or, alternatively, ink droplets ejected from the nozzle are deflected to be caught by a gutter which is independent of the first gutter for routing to disposal means. The amount of disposal is determined by a pressure of ink fed to the nozzle and/or a temperature of ink in the neighborhood of the nozzle.

Abstract: A disposable container for collecting waste liquid is disclosed. A casing has therein an absorption member for absorbing waste liquid toward the interior of the casing, and a liquid holding member held in contact with the absorption member to retain the waste liquid absorbed by the absorption member. The receptacle is applicable to an ink jet recording apparatus for collecting waste ink. A fresh ink container may be combined with the waste ink receptacle in an integral cartridge configuration to be mounted in an ink jet recorder.

Abstract: A method applicable to a character recognition system is disclosed which assigns direction codes to a number of boundary picture elements contained in a two-level character pattern. The direction of connectivity of a boundary picture element observed is fractionized to minimize the error due to the quantization of the direction. The direction codes are converted into those which correspond to connectivity directions which should be finally grasped. Such direction codes allow strokes to be extracted quite faithfully to the original character pattern.

Abstract: Light reflected from a reference pattern having a predetermined reflectivity is focused to a photoconductive element to form a latent image thereon. A degree of deposition of a toner on the latent image is sensed by a sensor and the toner supply to a developing unit is controlled in response to an output of the sensor. A fatigue standard is selected taking into account a fatigue characteristic particular to the photoconductor, so that a bias voltage applied to a developing roller in the developing unit is varied in response to the selected fatigue standard.

Abstract: An ink viscosity regulation apparatus for an ink jet printer is disclosed which controls the viscosity of ink to a value which lies within a range appropriate for printing. A signal commanding a supply of diluent into the ink is generated when a predetermined voltage level is exceeded by specific one of voltage levels for driving an electrostrictive vibrator of a head which causes a droplet to be separated from an ink stream at the shortest distance from the head.

Abstract: A support mechanism used for securely mounting a head, a charging electrode and a deflection electrode of an ink jet printer on a carriage. The mechanism includes a hollow cylindrical first holder for detachably holding the head and the charging electrode independently of each other, and a second holder for detachably holding the deflection electrode. The head, charging electrode and deflection electrode are readily mounted and demounted from their associated holders.

Abstract: A method of controlling an image density in electrophotography by controlling at least one of various image density parameters in response to values detected from different pattern areas, the image density parameters including an amount of charge deposited on a photoconductive element by a charger, bias voltage for development, toner concentration in a developer, amount of toner supply to a developing unit and image transfer potential. The method forms at least two pattern areas having different potentials on the surface of the photoconductive element by at least one of various means for forming charge patterns which include controlling the energization of the charger, controlling an illumination lamp and projecting an image pattern.

Abstract: An image compensating method and an apparatus for the same which improves the quality of an image to be reproduced by an image reproduction system. A condition of an observed pixel or object pixel is subjected to MTF compensation to provide clear cut boundaries to an image relative to the background. Then, random noise compensation is effected for the condition of the object pixel after the MTF compensation, taking account of conditions of surrounding pixels or MTF-compensated conditions of the surrounding pixels. This removes smear which might appear in a sheet of paper due to random noise. These two kinds of compensation allows an image to be reproduced to a remarkable quality.

Abstract: A magnet brush cleaning apparatus for removing a toner which has been left non-transferred on the surface of a photoconductive element. The residual toner is attracted by and supported on a rotary sleeve on which a magnetic carrier forms a magnet brush. The magnetic carrier separated from the magnet brush and the residual toner are separated from each other by an electrode which is disposed in a circulatory carrier supply path in order to develop an intense electric field. The thus separated carrier is returned to the sleeve. The electrode may take the form of a roller, a plate or a wire. The residual toner on the photoconductive element has its amount of charge reduced in advance by a discharging unit. A substantial amount of the residual toner is scraped off the photoconductive element by a fur brush. A desired amount of the carrier is discharged and replenished automatically in response to lowering of the cleaning ability of the apparatus.