Abstract: A developer processing apparatus includes a rotary member provided rotatably in a container containing the developer, a sealing member provided at the rotary member and being brought into pressure contact with a portion supporting the rotary member and a sealing layer provided at the portion where the sealing member is brought into pressure contact, and formed of a material having lower hardness than the sealing member.

Abstract: In a print head for a powder jet image forming apparatus according to the present invention, a grid electrode is provided between first electrodes and a developer supply roller in parallel with major surfaces of an insulating layer, and therefore, a distance between any of the first electrodes and the grid electrode is kept fixed. Thus, applying a given level of voltage to the grid electrode allows an electric field for supplying developer to the first electrodes to arise uniformly. This is effective in avoiding uneven density in the resultant image.

Abstract: The present invention relates to a print head in a powder jet image forming apparatus comprising a plurality of first electrodes formed on the surface of an insulating layer on the side of a developer supplying roller and a plurality of second electrodes formed on the surface of the insulating layer on the side of a paper conveying section, a developer through-hole being provided at each of intersections of the first electrodes and the second electrodes. In the present invention, one or a plurality of guard electrodes for drawing a developer from the developer supplying roller and supplying the developer to the first electrodes are provided around the first electrodes on the surface of the insulating layer.

Abstract: An image forming apparatus includes a developer supplying roller for supplying to a predetermined print position a developer charged to predetermined polarity, and a print head provided in the print position and having electrode pairs which are respectively provided with developer passing holes, each pair including a first electrode and a second electrode connecting with each other, and being so adapted that the developer passing holes are opened or closed by control of an electric field between the first and second electrodes, on the basis of whether print dot data is sent in synchronization with a predetermined print clock signal. At a time when the print dot data is sent in synchronism with the print clock signal, the electric field is controlled such that the developer is attracted from the developer supplying roller to the first electrode.

Abstract: An image forming apparatus is provided, in which a plurality of toner passage holes are formed in a board, and an image information generator applies a voltage between a pair of electrodes to form an electric field within each toner passage hole, so as to pass toner through the toner passage hole. The diameter and the axial length of each toner passage hole are so determined as to avoid clogging with toner.

Abstract: Disclosed is a toner for the electrophotography, which comprises as a main component a styrene/acrylic copolymer having at least two molecular weight distribution peaks, the molecular weight (Mw) of the peak on the lowest molecular weight side being lower than 13000, wherein the toner contains a charge controlling agent dispersed therein at a concentration of at least 0.3% by weight and the charge controlling agent has such a particle size distribution that the area ratio of particles having a particle size larger than 2.5 .mu.m is at least 80% based on the section of the toner. If this toner is used, the fixing-possible temperature can be broadened while increasing the fixing ratio without reduction of the performances of the toner.

Abstract: In an electronic fuel injection control device for an internal combustion engine, an A-D converter is provided to convert an analogue signal indicative of a physical value such as an intake manifold negative pressure or an amount of suction air to a digital value, and a computer is programmed to calculate an average of a plurality of the digital values successively converted during one rotation of the engine, to determine whether or not a difference between the preceding average of the digital signals and the following average of the digital signals is larger than a predetermined value indicative of a transient operation of the engine, if so determine a first optimum physical value based on an average of at least two digital values most newly converted during one rotation of the engine, and if not determine a second optimum physical value based on the average of the digital values, and to determine an optimum fuel injection time based on one of the first and second optimum physical values and in relation to r

Abstract: In a fuel supply apparatus for an internal combustion engine, asynchronous fuel supply or injection is effected in addition to synchronous fuel injection so as to increase fuel amount on acceleration. In order to reduce time lag for supplying additional fuel, the opening degree and opening speed of a throttle valve of the engine are detected, and additional fuel supply by way of asynchronous fuel injection is effected whenever it is determined that the state of the throttle valve represents a state where fuel increase is required. Asynchronous fuel supply is then stopped when the opening degree of the throttle valve reaches an upper limit determined by the detected opening speed of the throttle valve, thereby avoiding application of excessively rich mixture.

Abstract: An intake pipe of an internal combustion engine is formed with an air passageway so as to bypass a throttle valve portion and an air control valve to control the amount of the air flowing through this passageway is provided for this air passageway. This control valve is constituted so as to drive an actuator in accordance with the amount of an exciting current and thereby to control the amount of the air which flows through this passageway. An exciting coil of this control valve is heated and controlled by the cooling water of the internal combustion engine. When the internal combustion engine is in the idle operation state and also in the feedback control state, the temperature of the cooling water is detected. In the case where this temperature falls within a specified range, a correction value of a control amount for feedback control to allow the present rotating speed of the internal combustion engine to approach the idle objective rotating speed is calculated and stored.

Abstract: An air-fuel ratio control system applicable to engines having exhaust gas recirculation (EGR). A basic amount of fuel to be injected is determined on the basis of an intake air pressure or a throttle opening. When the operating condition of an engine meets a predetermined condition for an exhaust gas recirculation control mode, a correction coefficient for the exhaust gas recirculation control mode is read from map data stored in memory means to correct the basic amount therewith. Immediately after the correction coefficient has been changed, the basic amount is corrected with a correction coefficient related to the values of the correction coefficient immediately before and after it is changed.

Abstract: An intake air amount control apparatus of an internal combustion engine controls an air control valve provided at a by-path formed with respect to a throttle valve which is provided in an intake air path of the engine. When the open-loop control mode of the engine is set, the apparatus determines which of the feedback loop and the open-loop control mode has been performed. When it is found that the feedback loop control mode has been switched to the open-loop control mode, a control amount corresponding to a current cooling water temperature of the engine is read out from a preset map, thus preparing for the following open-loop control. Simultaneously, a control amount in the previous feedback control mode is read out, and a current open-loop control amount is calculated by adding a compensation value to the thus read-out control amount. When it is determined that the open-loop control mode is continuously performed, a control amount corresponding to the current cooling water temperature is read from the map.

Abstract: A closed-loop mixture control system for an internal combustion engine comprises an intake air pressure sensor, an engine speed sensor, an exhaust gas sensor for detecting the concentration of a predetermined composition of exhaust emissions from said engine, said concentration varying as a function of the air-fuel ratio of a mixture supplied to the engine, a memory having a plurality of storage locations, and a data processor. The processor derives a basic quantity of fuel to be injected to the engine as a function of the detected pressure and engine speed, a mixture trimming value as a function of the detected concentration, a fuel injection trimming value dependent on the mixture trimming value, and stores the fuel injection trimming value into a memory location exclusively addressable as a function of the detected engine speed.

Abstract: In an air flow control apparatus for controlling an amount of air flow under control of a throttle valve in an engine, a sensor produces a first signal indicative of engine operation, and another sensor produces a second signal indicative of the atmospheric pressure. A microcomputer determines whether or not the first signal indicates an idling condition of the engine. If so, the microcomputer calculates, in dependence upon the first signal, a first parameter indicative of an amount of the air flow necessary for maintaining a desired idling condition of the engine. If not, the microcomputer calculates, in dependence upon the first signal, a second parameter indicative of an amount of the air flow related to loaded condition of the engine.

Abstract: Idling speed of the internal combustion engine is controlled to a predetermined engine speed by correcting an engine operating parameter, such as, an ignition timing, the quantity of fuel injection, etc., to suppress a variation rate of the engine torque. Instead of detecting the torque variation rate directly, an engine speed variation rate is detected, and a correction value of the engine parameter is determined as a function of the engine speed variation rate based on the finding that the torque variation rate can be approximated as the engine speed variation rate with a fixed phase difference therebetween. Since the phase difference is determined by the engine speed, a correction value at the present moment is obtained from the previously obtained correction value which is preceding by the phase difference.