Abstract: A plurality of copying machines (12), (13), (14) are connected to a computer (39). Each copying machine (12), (13), (14) comprises sensor means (16), (17), (18), (19), (21), (22), (23), (24) for sensing various operating parameters thereof such as a total number of copies produced, machine malfunctions, amounts of remaining copy sheets and toner, etc. These parameters are all transmitted to the computer (39) which processes and prints them out. In response to a copying machine malfunction the computer (39) feeds back to the malfunctioning copying machine instructions for correction. The instructions are displayed at the copying machine. The computer (39) further computes the degree of degeneration of the photoconductive element of each copying machine (12), (13), (14) and controls the imaging exposure intensity and developing bias voltage in accordance therewith.

Abstract: A facsimile communication control system for setting up a modem rate appropriate for a remote receiving station within a short period of time. A modem rate used for communication last time is stored in a nonvolatile memory so that a modem training at the time of the next communication begins with the stored modem rate. Where the transmit station is to hold a communication with a new remote station for the first time, the modem training begins with the highest modem rate which is shared by the two stations as heretofore practiced.

Abstract: An optical disc recording and playback apparatus has a record/playback head adapted to write data into and read them out of information tracks formed on a rotatable optical disc. A carriage carrying the head therewith is driven by a linear motor in the radial direction of the disc perpendicular to the tracks, and then stopped and held at a desired track position. Thereafter, a tracking control is performed by allowing the head to move in the radial direction within a predetermined range.

Abstract: A control device for a copier varies a magnification such that images on different sizes of documents are accommodated in a single predetermined size of copy sheets. The control device includes a read only memory for storing magnification data which are optimum for various combinations of a document size, a copy sheet size and a document orientation, a proper magnification check flag indicative of whether a selected magnification is proper and a document orientation check flag indicative of whether a selected orientation of a document is proper.

Abstract: A picture signal quantizing circuit for quantizing with respect to multiple levels an analog picture signal read from a document by converting it into a digital picture signal which has a plurality of bits. An AD converter is installed in the circuit which is supplied with reference voltages corresponding to the highest and lowest levels for quantization and prepared by dividing a document background level voltage, multi-level quantizing the analog picture signal within the range defined by the two levels. The AD converter includes a circuit for accentuating half-tone of the analog picture signal to enhance the reproducibility thereof.

Abstract: A toner charging member to which a toner is conveyed and supplied is located in the vicinity of a photoconductive element which is to carry an electrostatic latent image thereon. The toner charging member charges the toner conveyed thereto to a selected polarity by friction, so that a thin uniformly charged toner layer is formed on the toner charging member. The charged toner particles are released from the toner layer on the charging member onto the latent image on the photoconductive element.The toner charging member has an insulating member on its surface. A first discharging means is provided to dissipate accumulated charge on the insulator substantially simultaneously with its operation for removing toner particles from the charging member those which were not been supplied to the latent image.

Abstract: A toner charging member to which a toner is conveyed and supplied is located in the vicinity of a photoconductive element which is to carry an electrostatic latent image thereon. The toner charging member charges the toner conveyed thereto to a selected polarity by friction, so that a thin uniformly charged toner layer is formed on the toner charging member. The charged toner particles are released from the toner layer on the charging member onto the latent image on the photoconductive element.The toner charging member has an insulating member on its surface. A first discharging means is provided to dissipate accumulated charge on the insulator substantially simultaneously with its operation for removing toner particles from the charging member those which were not been supplied to the latent image.

Abstract: A dry process developing apparatus for a copier or like machine is constructed to prevent a toner from scattering inside the machine. The toner is transported to a surface of a photoconductive element via an opening which is formed through part of a casing adapted to store the toner. First and second screening means are detachably mounted on the casing and arranged to cover a front open portion between the surface of the photoconductive element and the casing of the developing apparatus as well as side open portions.

Abstract: A variable magnification imaging device for a copier employs a swingable mirror assembly and a cam and follower mechanism for regulating the angular position of the mirror assembly. As a carriage supporting a lens thereon moves along an optical axis toward and away from the mirror assembly, the mirror assembly is caused to swing automatically to a desired magnification position through a parallelogram link mechanism, while having its angular position properly regulated by the cam and follower mechanism.

Abstract: An image density control method for electrophotography which controls at least one of various image density parameters in response to values detected from different pattern areas. The image density parameters include an amount of charge deposited on a photoconductive element by a charger, bias voltage for development, toner density in a developer, amount of toner supply to a developing unit and transfer potential. At least two pattern areas having different potentials are formed 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 illuminating lamp and projecting an image pattern.

Abstract: A cleaning device includes a rotatable cleaning sleeve and magnets housed in the cleaning sleeve in order to remove residual toner particles from a photoconductive element of an electrophotographic copier or the like, which is supported by a frame in the form of a belt or a sheet. A pressing mechanism is employed to maintain the surface of the photoconductive element in pressing contact with the cleaning sleeve. The pressing mechanism comprises a pressing member which includes a soft member and is magnetically attracted by the magnets in the sleeve to cause the photoconductive element into pressing contact with the cleaning sleeve, and an urging member consisting of a magnetic member or a magnet and also magnetically attracted for urging the frame toward the cleaning sleeve. Pressure force magnifying members are provided for magnifying the pressure force in laterally opposite end portions of the photoconductive element.

Abstract: A single temperature sensing switch is responsive to two or more different ambient temperatures is disclosed. A contact mechanism made up of stationary and movable contacts is opened and closed by serially interconnected first and second temperature-sensitive members, which are made of shape memorizing alloys having different transformation points. The switch may be associated with a compressor of an automotive air conditioning system in order to prevent it from being heated beyond a siezing level or cooled beyond a liquid compressing level.

Abstract: A record head of an image recording apparatus is reciprocally tilted to suitably vary the contact condition between the surface of the record head and that of a recording medium, thereby removing toner particles which are momentarily stuck to the record head surface. To maintain styluses of the head unchanged in position, the reciprocation of the record head is effected for the interval between the end of a recording cycle for one page and the start of the next recording cycle for another page, which interval has no influence on the image recording operation.

Abstract: At least two movable objects are respectively driven to move by servo motors or the like in response to independent drive start signals. When each of the objects reaches a predetermined position, a sync signal associated therewith is generated. If a time lag exists between the generation of the sync signals, one of the drive start signals supplied to the servo motors is delayed by a period of time which corresponds to the time lag.

Abstract: A drive circuit for controllably driving a heater which is used for maintaining ink in an ink jet printer at a predetermined temperature. A plurality of power sources are installed in the circuit each for supplying a voltage to the heater. The power sources are selectively connected to the heater by a plurality of output transistors and an error amplifier adapted to control switching actions of the output transistors. Diodes are interposed between the respective transistors and the error amplifier to enhance the linearity of the level of the voltage supplied to the heater.

Abstract: An image recording apparatus which sequentially performs a series of electrostatic or electrophotographic recording steps in accordance with the movement of a recording medium which is shaped as an endless belt. A section of the apparatus adapted to movably pass the belt around a drive roller, idle rollers and a tension roller have a unitary cassette configuration. Chargers, a recording head and other instruments located above the belt cassette are commonly mounted on a single base member. The belt cassette and base constitute an upper unit which is bodily movable away from a housing of the apparatus toward an open position thereof.

Abstract: A unique arrangement of a multi-nozzle head which is suitable for use with an ink on-demand type ink jet printer. A flat head base is formed with a plurality of nozzles and ink compressing chambers associated therewith by etching. The ink compressing chambers are divided into a plurality of groups which are positioned on imaginary lines, which are individually inclined a predetermined angle with respect to an intended direction of ink ejection.

Abstract: A pump furnished with an electrostrictive vibrator which pressurizes ink to be supplied to a head of an ink jet printer. The electrostrictive vibrator is adhered at one end to a diaphragm which closes an ink pressurization chamber, so that the vibrator vibrates integrally with the diaphragm perpendicularly to a plane in which it is adhered to the diaphragm, thereby varying the volume of the pressurization chamber. A vibrator drive signal supply circuit is installed in the pump which includes a time constant generation circuit adapted to apply a time constant to the waveform of a drive signal applied to the vibrator at the time of buildups and falls of the drive signal.

Abstract: A deflection control type ink jet recording apparatus is capable of automatically removing a failure in ink ejection. A condition set control is performed to set a predetermined charging and deflection condition for ink drops. If the condition set control fails to predetermine the desired condition, ink ejection is interrupted and, after a predetermined period of time, a second condition set control is performed. The interruption time of ink ejection is predetermined to be shorter than a predetermined period of condition set controls which occur during a print control, thereby shortening the down time when the condition setting operation is not successful.

Abstract: A power source circuit for a charge and deflection type ink jet printer which supplies deflection voltages to at least two separate deflection electrodes. The circuit performs a control such that output voltages of two shapers commonly connected to a secondary winding of a transformer are substantially equal to each other.