Abstract: A direct driving mechanism moves, in a direct drive manner, at least one of a sheet, on which an original image to be read is realized, and an image reading system for reading the original image so that the image reading system progressively reads all of the original image accordingly. The image scanning mechanism has an arrangement for reading the original image realized on the sheet either in a first mode of sensing light reflected by the sheet or in a second mode of sensing light transmitted by the sheet. The arrangement includes at least two different kinds of driving mechanisms, each being used for a respective one of the first and second manners. At least one of the two different kinds of driving mechanisms includes the direct driving mechanism.

Abstract: A drive device for a travel assembly for use in an optical system of an image read scanner, a printer head, etc. The drive device includes a wire rope for driving the travel assembly at each side thereof, one end of each wire rope being fastened to the travel assembly through a spring and a one-way clutch. This one-way clutch is so designed that it cannot rotate when the wire rope is tight for driving the travel assembly, which results in no fluctuation in motion of the travel assembly caused by an elongation or contraction of the spring. The one-way clutch can rotate for permitting the spring to absorb the aforesaid elongation or sagging of the wire rope only while the travel assembly is at rest.

Abstract: A support device for supporting on a guide shaft a travel assembly moving along the guide shaft, comprising at least two sliding bearings equipped with V shaped grooves, and separate bearings disposed opposite the respective sliding bearings across the guide shaft. The support device supports the travel assembly on the guide shaft by pinching the guide shaft between the sliding bearings and the separate bearings.

Abstract: An optical system for directing a light image of a scanned original to a charged photosensitive surface of an electrophotographic copying apparatus, includes an imaging lens located between the original and the photosensitive surface. The optical axis of the imaging lens is directed normally to the original and the lens is movable in a direction substantially parallel to the original during scanning of the original. At least one mirror is disposed to receive the imaging rays from the imaging lens to reflect them onto the photosensitive surface, and each mirror is moved synchronously in a different direction from the lens to maintain the rays reflected from the original at a proper position during scanning.

Abstract: An electrophotographic copying machine capable of making a two-dimensional copy either from a two-dimensional or three-dimensional object is provided. In accordance with the present invention, if a three-dimensional object has portions which cannot be brought into contact with the top surface of the contact glass plate of the copying machine, adjusting means adjusts the focal distance to the location of such non-contact portions. The adjusting means may be any element of the optical system which is constructed to be shiftable to change the focal distance to a point of interest above the contact glass plate. Alternatively, the adjusting means may include a new element additional to the optical system.

Abstract: A variable magnification and reciprocal exposure copying method in which the image of an original is introduced onto a photoconductor which is moved in a predetermined direction by reciprocating mirrors relative to the original, so that the photoconductor is exposed to the light image of the original during the forward movement and backward movement, and an auxiliary lens for variable magnification is disposed in such a manner that it can be shifted from or into the optical path in front of or behind an inverted optical system for use in the forward movement or an erecting optical system for use in the backward movement, so that reciprocal, variable magnification copying can be performed.

Abstract: An alarm system for the copying machine for giving the audio or visual alarm signal when an operator leaves a copying machine without taking a master or original out of it after a copying operation. The alarm system includes a master detection means for detecting whether or not a master or original is set on a master or original stand and either a copy detection means for detecting whether or not one or more copies are present in a copy discharge tray or an operator detection means for detecting whether an operator is within a predetermined range from the copying machine.

Abstract: The surface of a photoconductor is moved in a predetermined direction and the original is scanned reciprocally by the relative movement of an optical system relative to the original. The photoconductor is exposed not only at the forward original scanning, but also at the backward original scanning through an exposure optical path which is different from that at the forward original scanning. The relative shifting of the original and the optical system is performed regardless of the size of the original and can be always performed in the full area in the scanning direction for the maximum size original, and the shift distance can be changed depending upon the size of the original. The original is placed on an original stacking surface in conformity with the two references in the scanning direction and in the transverse direction by use of the two end edge portions.

Abstract: A glass pane on which an original is placed and a focusing lens are stationary in the space of a copying machine. An original to be copied is placed on the glass pane in planar form. A pair of reflecting mirrors disposed on the image side of the focusing lens successively reflect exposing light flux from the focusing lens to pass it onto an exposure station on the photosensitive member. The surface of the photosensitive member moves in a given direction at a uniform rate while the pair of reflecting mirrors move in independent directions to achieve a slitwise exposure of the photosensitive member at a given location.

Abstract: An original feeding system having a rotary drum provided with sheet original hold-down claws for clamping the leading edge of the sheet original against the surface of the periphery of the rotary drum and with a control mechanism for keeping the claws in clamping engagement with the sheet and releasing the claws from clamping engaging therewith. A belt drive is provided for feeding the copy sheet by holding same between the rotary drum and the belt. The rotary drum is adapted to be stopped in its rotation before it completes one revolution, while the belt drive continues to be driven to feed the sheet original, which is subjected to the frictional force exerted by the belt and slides along the surface of the rotary drum. Therefore, it is possible to feed a sheet original having a length larger than the circumferential length of the rotary drum.

Abstract: An improved electrophotographic copying apparatus is described, which permits, during automatic copying of a desired number of copies from the same original document, the setting of the number of repeated uses of the same latent electrostatic image, thus obviating the lowering and unevenness of image quality of the copies. In another embodiment of the improved electrophotographic copying apparatus, the timing of the formation of successive latent images of the same original document is controlled in accordance with the total number of copies to be made of the same original document so that the number of repeated uses of each respective latent image is made approximately equal. Also, in the latter embodiment, a signal indicating the timing for the exchange of successive original documents is generated at the time of formation of the last electrostatic image from the prior original document.

Abstract: A variable magnification optical system focusses an image of a portion of an original document on a platen through a variable aperture or slit onto a rotating photoconductive drum. Various members of the optical system or the document are moved at a speed corresponding to the surface speed of the drum to scan the document and form an electrostatic image thereof on the drum. The slit is defined by a fixed aperture plate and a movable aperture plate disposed upstream of the fixed aperture plate in the direction of rotation of the drum. A variable transmission connected between an exposure knob and the movable aperture plate transmits rotation of the knob to the movable aperture plate at a rate corresponding to the magnification. In addition, a side edge of the document is aligned at the same position for all magnifications. The movable aperture plate is formed with a curved edge facing the fixed aperture plate, the center of the curved edge being aligned with the center of the image at all magnifications.

Abstract: First and second original documents are copied on the opposite sides of a copy sheet in superposition in such a manner that the centers of the two copied images on the opposite sides of the copy sheet are coincident with each other. The two copied images are offset from the center of the copy sheet, leaving a blank area at one edge of the copy sheet for binding a number of copy sheets together in book form. The present copying machine is further provided with two sheet cassettes containing copy sheets of different sizes, a device for selecting the desired copy sheet size and intermediate sheet holder for temporarily holding the selected copy sheet between the copy operations of the first and second original documents.

Abstract: The auto document feeder is for use with duplex copying machines, and is capable of inverting duplex sheet originals, having images on both surfaces, automatically and feeding the originals to an exposure station automatically. The feeder comprises trays for stacking a plurality of sheet originals to be copied, sheet feeding devices for feeding the sheet originals individually from the trays to the exposure station, a platen belt mounted on the exposure station and operable to transport a sheet original across the exposure station and to maintain each sheet original in close contact with the exposure station during exposure of the sheet original, from either side of the exposure station, sheet inverting devices for inverting sheet originals received from the exposure station, and a sheet transport device for transporting inverted sheet originals to the exposure station for completing the duplex copy.

Abstract: In successively copying a plurality of continuous pages of a book original by means of a copying apparatus adapted to print images of the pages on opposite surfaces of each copy sheet, a printing operation is controlled in such a manner that a series of processes including, illumination of the pages, charging and exposing of a photosensitive drum, developing, fixing and transfer printing of visible images, and ejection of printed copy sheets is automatically performed, if the book original is opened at desired pages and placed on an original placing glass plate of the copying apparatus in a normal condition in which the top of the book original is remote from the operator.

Abstract: A duplex copying machine has an auto document feeder and is capable of duplex copying from originals having images on one side, originals having images on both sides and combinations of the aforementioned two types. In a preferred embodiment of the duplex copying machine, whether an original has images on one side only or on both sides is detected so as to obtain a duplex copy from a duplex original and a one-side copy from a one-side original.

Abstract: First and second original documents are copied on the opposite sides of a copy sheet in superposition in such a manner that the centers of the two copied images on the opposite sides of the copy sheet are coincident with each other. The two copied images are offset from the center of the copy sheet, leaving a blank area at one edge of the copy sheet for binding a number of copy sheets together in book form. The present copying machine is further provided with two sheet cassettes containing copy sheets of different sizes, means for selecting the desired copy sheet size and intermediate sheet holder means for temporarily holding the selected copy sheet between the copy operations of the first and second original documents.

Abstract: The surface of an electrostatic drum (12) is charged and radiated with a light image of an original document (16) to form an electrostatic image which is developed to form a toner image. A copy sheet (18) is moved into engagement with the drum (12) and an electrostatic charge applied thereto to transfer the toner image to the copy sheet (18). A corona discharge unit (27) applies an alternating voltage to the leading edge of the copy sheet (18) to discharge the same and cause the leading edge to separate from the drum (12). Thereafter, the discharge unit (27) applies an asymmetrical alternating voltage which partially discharges the remaining portion of the copy sheet (18) but does not cause the same to separate from the drum (12).

Abstract: In the method, two originals are placed side-by-side on the contact glass of an electrophotographic duplex copying machine and are scanned successively, in a single scanning operation, by the exposure optical system of the machine to form respective successive images on a photoconductive drum rotated past an image transfer device. Two transfer sheets are fed successively, with a short interval therebetween, from a primary supply device for transfer sheets, past the image transfer device in synchronism with the image formation on the drum, to provide duplex copies, having images in the same relation as that of the two originals, in a single copying cycle or process. By utilizing a secondary sheet supply device and a suitable switching device, images can be provided on both sides or surfaces of a transfer sheet or sheets. The duplex copying apparatus includes a novel sheet feed device effective to stack transfer sheets neatly.

Abstract: A large number of copies of a small original document such as a card are made quickly by forming electrostatic images of the document circumferentially spaced from each other on the periphery of a rotating photoconductive drum. The electrostatic images are repeatedly developed and the resulting toner images are transferred to respective copy sheets to form copies. In this manner, a number of copies equal to the number of electrostatic images on the drum are produced for each revolution of the drum. However, due to unavoidable discharge of the electrostatic images the same can only be developed a predetermined number of times if acceptable copies are to be produced. The present apparatus therefore comprises an automatic means for forming new electrostatic images when the original electrostatic images have been developed the predetermined number of times. The automatic means may be in the form of a counter, a timer or a voltage sensor.