Abstract: An image forming apparatus is so arranged as to form an image of an original document on a photosensitive member by accommodating the plate-like photosensitive member of a rectangular or square configuration placed on an exposure section base in a housing of the image forming apparatus. The exposure section base is disengageable from the housing in a horizontal direction and has a plurality of suction holes in a region on which the photosensitive member is placed. A switch detects when the exposure section base is inserted into the housing to reach a predetermined position, and a suction device then sucks air through the suction holes.

Abstract: A cleaning device for an image-carrying member includes an elastic blade having a proximal end fixed to a holder and a terminal end held against the image-carrying member for removing toner from the image-carrying member upon movement of the image-carrying member. The terminal end of the blade flexes to extend forward in the direction of movement of the image-carrying member at an angle of .alpha. to a line tangential to a surface of the image carrying member rearward of a contact point between the terminal end of the blade and the image carrying member with respect to the direction of movement thereof. The blade has an axis passing through the proximal end of the blade and extending at an angle of .theta. to the tangent rearward of the contact point with respect to the direction of movement of the image-carrying member. The angles .alpha. and .theta. are selected to meet the following relationship:.theta.>90.degree.>.alpha..

Abstract: A cleaning device for use on a transfer type electrostatic copying apparatus includes a magnetic brush cleaning device for cleaning off a magnetizable toner remaining on a photosensitive material after a transfer operation. A brush roller is disposed between the magnetic brush cleaning device and a transfer zone. A brush is arranged on a peripheral surface of a cylindrical sleeve of light transmitting material and is driven for rotation in contact with the photosensitive material. A charge eraser lamp is secured within the cylindrical sleeve. The charge on the photosensitive material or photoreceptor is almost completely erased, and consequently, the cleaning efficiency is markedly improved owing to the facilitated removal of the developing material by the magnetic brush.

Abstract: A roller supporting arrangement for an electrostatic copying apparatus having a plurality of pairs of copy paper transport rollers spaced along a copy paper transport passage includes a support frame for supporting the lower rollers of the respective pairs of transport rollers. A support shaft is mounted horizontally to a copying apparatus housing, by which the support frame is rotatably supported. A device is provided for pushing up the support frame and for releasing the support frame from the push-up force to be turned downward about the support shaft. Since the lower rollers of the pairs of the rollers mounted at the copy paper sheet transport passage are connected pivotally to the support frame which is rotatable about the horizontal support shaft, it is easy to open the copy paper sheet transport passage when a copy paper is jammed in the copy paper sheet transport passage.

Abstract: A detecting device for detecting when the amount of toner in a dual component developing material is less than a predetermined level includes a hopper for supplying the toner, a stirring roller for stirring a carrier and the toner from the hopper, and a detector for detecting the amount of developing material provided near the stirring roller to mix the toner supplied from the hopper with the carrier. A discriminator discriminates an output signal from the detector for a predetermined interval during the rotational period of the stirring roller. An indicating element operates in response to the output signal from the discriminator to indicate when the amount of the toner in the developing material is less than the predetermined level. Since it is indicated when the toner in the developing material is less than the predetermined level, the toner is supplied according to such indication, and therefore, an undesirable deterioration of copy density is prevented.

Abstract: A particulate composite developer for electrophotography is disclosed, which has a novel dispersion structure comprising a continuous phase consisting of a homogeneous mixture of a resin and a pigment and a dispersed phase consisting of spherical particles of a soft parting or fixing material having an emulsion grade size and being dispersed in the continuous phase. This particulate developer has in combination improved adaptability to the developing operation, excellent transferring and cleaning properties, good ability to form a sharp image free of fog and good fixing property not causing an offset phenomenon.

Abstract: The present invention relates to a developing material supplying control device for an electrostatic copying apparatus which includes an oscillator circuit composed of an oscillation coil provided along a toner supplying passage, a timer, a counter for counting the output signal from the oscillation circuit at every interval predetermined by the timer to supply a discriminating output signal when the counted value is equal to a predetermined value for each of the intervals. A toner supply acts in response to the discriminating output signal from the counter for supplying toner to the toner supplying passage. Since this invention employs the oscillation coil and does not employ a mechanical switch having a movable contact for detecting toner in the toner supplying passage, the toner supplying operation is achieved precisely.

Abstract: A photosensitive drum assembly for an electrostatic copying apparatus includes a cylindrical drum having a photosensitive layer provided around its outer periphery. The drum is held between a pair of flanges at opposite axial ends of the drum. Each of the flanges is formed having a diameter larger than the external diameter of the drum. At the edge of each flange, is a cylindrical portion extending along the axis of the drum to face toward the opposite flange. The end edges of the drum closely fit into the cylindrical portions. According to the present invention, since the edges of the drum closely fit into the cylindrical portions of the flanges, it is not necessary to improve the dimensional accuracy of the inside periphery of the opposite ends of the drum, while it is essential to improve the dimensional accuracy in a conventional manner.

Abstract: A developer for electrostatic images consisting essentially of particles comprising a pigment, a binder and an offset-preventing agent selected from the group consisting of aliphatic fluorocarbon compounds and fluorochlorocarbon compounds is disclosed. When this developer is used, a high offset-preventing effect can be attained at the fixing step even if the amount incorporated of the offset-preventing agent is small, and further, the developing operation can be performed in good conditions. By incorporation of this offset-preventing agent, the flowability of particles of the developer and charge characteristics of the developer can be remarkably improved.

Abstract: A fixing and heating device for an electrostatic copying apparatus includes a fixing roller which (a) remains stationary at least until a toner is softened, (b) is driven at a low speed to even the surface temperature of the fixing roller when the surface temperature is lower than a temperature suitable for fixing, and is equal to the temperature suitable for fixing except during a fixing operation, and (c) is driven at a speed suitable for fixing when the surface temperature is suitable for fixing during the fixing operation.

Abstract: An electrostatic copying apparatus is provided wherein a stationary original document image is projected onto a photosensitive member during movement of an optical device for exposure. An electrostatic latent image formed on the photosensitive member is transferred onto a copy sheet and is fixed. A jam detecting means is provided for immediately detecting a copy sheet being jammed along a transport path. A cleaning device removes residual toner particles remaining on the photosensitive member by means of magnetic force and stores the removed toner particles after a transferring operation. The occurrence of a jam is detected immediately, and thus a fault or an accident of the electrostatic copying apparatus due to the jam is prevented from continuing.

Abstract: A plate for lithography or offset printing comprising a flexible substrate and a water-resistant coating layer formed on the flexible substrate, said water-resistant coating layer being composed of a water-insoluble resin binder and an inorganic pigment dispersed in said binder, and the water-resistant coating layer including an oleophilic ink-supporting portion composed of particles consisting essentially of at least one member selected from triiron tetroxide and .gamma.-type diiron trioxide, the particles being embedded in at least a part of the surface of the coating layer, and an etched hydrophilic ink-repelling portion composed of the inorganic pigment.

Abstract: A transfer film comprising a transparent plastic film substrate, an undercoating layer composed of an electrically conductive resin and having a surface resistance of 1.0.times.10.sup.6 to 9.0.times.10.sup.9 .OMEGA., and a toner receiving layer composed of a binder resin and having a surface resistance of 1.0.times.10.sup.10 to 1.0.times.10.sup.14 .OMEGA., which is formed on at least one surface of the transparent plastic film substrate through the undercoating layer.

Abstract: A supporting mechanism of a document cover lid to be used for a copying apparatus includes a base of a supporting member mounted to the upper portion of an apparatus housing so as to swing about a horizontal axis. A positioning member is mounted on one of either the apparatus housing or the supporting member has a first frictional surface which is a circular periphery in a vertical plane with respect to the horizontal axis. A contact member is mounted on the other of either the apparatus housing or the supporting member and, has a second frictional surface, which is a circular periphery in a vertical plane with respect to the horizontal axis and is elastically pushed against the first frictional surface. By this mechanism, it is possible to support the document cover lid in an opened position upwardly at an angle sufficient to replace an original document.

Abstract: A fixing and heating device for an electrostatic copying apparatus includes a fixing roller which (a) remains stationary at least until a toner is softened, (b) is driven at a low speed to even the surface temperature of the fixing roller when the surface temperature is lower than a temperature suitable for fixing when the surface temperature and is equal to the temperature suitable for fixing except during a fixing operation, and (c) is driven at a speed suitable for fixing when the surface temperature is suitable for fixing during the fixing operation.

Abstract: A cutting apparatus for an electrostatic copying machine includes a fixed blade having a straight cutting edge, a rotary shaft mounted for rotation on the frame of the machine, and a rotary fixed to an carried by the rotary shaft, the rotary blade having a spirally curved cutting edge. A wrap spring clutch is capable of transmitting rotation of a continually rotating gear to the rotary shaft and rotary blade. The wrap spring clutch is prevented from operation by a control cog of a double cog member. An inclinable member operates the double cog member to release the wrap spring clutch to enable rotation of the rotary shaft and rotary blade. The double cog member has a rotation lock cog which stops the wrap spring clutch after a predetermined rotation of the rotary shaft and rotary blade.

Abstract: An exposure adjustment device for an electrostatic copying apparatus provides that electric power of an exposure lamp is controlled by pressing a key so as to cause copy density over a surface of a photoconductive member to be adjusted. The exposure lamp is energized electrically subsequent to change a of copy density from a set level to a standard level predetermined for obtaining an ordinary copy when a period predetermined by a timer elapses after copying operation finished and/or after the key is operated. This results in that the copy density of exposure is accomplished properly even if an operator forgets to adjust the copy density of exposure.

Abstract: A copying apparatus includes a copy paper cutting device which is operated when an original document or an optical device for exposure reaches a predetermined position. The original document or the optical device is stopped when a trailing edge of a copy paper is detected. After at least the leading edge of the copy paper passes through the copy paper cutting device, the copy paper is fed out entirely from an apparatus frame without operating the copy paper cutting device. This results in that the last copy paper sheet of the roll of copy paper is not shorter than the distance between transport rollers in the copy paper passageway to prevent a copy paper jam.

Abstract: A particulate composite developer for electrophotography is disclosed, which has a novel dispersion structure comprising a continuous phase consisting of a homogeneous mixture of a resin and a pigment and a dispersed phase consisting of spherical particles of a soft parting or fixing material having an emulsion grade size and being dispersed in the continuous phase. This particulate developer has in combination improved adaptability to the developing operation, excellent transferring and cleaning properties, good ability to form a sharp image free of fog and good fixing property not causing an offset phenomenon.

Abstract: A mechanism for supporting a cover lid, particularly an original document cover lid of an electrostatic copying apparatus, includes a generally U-shaped support member for supporting the cover lid. A pair of arms of the support member are fixed to a pair of hinge members which are mounted on the machine frame for rotation about an axis. Support pieces are fixed to the hinge members for rotation therewith about the axis. First springs are connected to the support pieces for urging the hinge members, the support member and the cover lid to rotate about the axis in a first direction toward an open position of the cover lid. A revolving plate is pivotally mounted on the machine frame, and a support bar is fixed to one of the hinge members and extends into an elongated opening of the revolving plate, such that rotation of the hinge members around the axis causes the support bar to pivot the revolving plate between first and second positions.