Abstract: An apparatus in which a latent image is developed with developer material. An applicator roller has developer material adhering releasably to at least a portion of the exterior surface thereof. The applicator roller rotates and translates from an non-operative position spaced from the latent image to an operative position closely adjacent the latent image. In this way, the applicator roller transports developer material to the latent image. After development is completed, rotation and translation of the applicator roller is reversed to return the applicator roller to the non-operative position terminating development. An apparatus of this type is used in a multicolor electrophotographic printing machine wherein successive latent images are developed with different color developer materials and the respective developer materials are prevented from co-mingling on the same latent image.

Abstract: An image-forming machine comprising a main body of the machine and an image bearing member disposed within the main body and adapted to form an image on a electrophotographic material disposed of the surface of the image bearing member. According to a first aspect, the main body of the image-forming machine includes a lower supporting frame and an upper supporting frame mounted on the lower supporting frame for free pivotable movement between an open position and a closed position, and a cover member mounted on the upper supporting frame, in which when the upper supporting frame is held at the open position, the cover member covers part of the image bearing member. According to a second aspect, an image-forming area and a non-image-forming area exist on the surface of the image bearing member, and when an image-forming step is over, the non-image-forming are is positioned at a transfer opening formed for image transfer.

Abstract: A device for controlling the density of toner of different colors individually stored in a plurality of developing units which are arranged around a photoconductive element senses toner density at a predetermined period which differs from one of the developing units to another. Each of the developing units is associated with a different kind of toner density sensing device.

Abstract: A developing method for developing an image on an electrophotographic film by means of a processing head which has a developing section to which the film is pressed for the development under the supply of a developer. After completion of supply of the developer to the developing section, weak and strong blasts of air are successively applied and, when the film is moved apart from the developing section, a final strong blast of air is applied, so that surplus residual liquid developer is removed from the developing section without being dried and solidified in the developing section.

Abstract: An image duplicating apparatus having a document table for supporting a document sheet thereon divides an image area of the document into two sections and successively duplicates the respective images of the two sections onto two separate copy surfaces. Switches specify the ratio by which an image on the document sheet is to be magnified or reduced for. An image magnification/reduction lens unit responds to the switches for altering a currently established magnification or reduction ratio to the newly specified ratio of magnification or reduction. A control circuit controls the duplicating means so that, when the magnification or reduction ratio is altered prior to termination of the duplication of a first one of the two sections, a second one of the two sections is copied in the altered magnification or reduction ratio.

Abstract: There is an image forming apparatus in which images of a plurality of originals set on the original plate glass are individually exposed, scanned and read, and the read images are synthesized and recorded at arbitrary positions on a recording paper. This apparatus also has a device to record the images on the front and back surfaces of the recording paper. The synthetic recording and the front and back surface recording can be arbitrarily switched and selected. This apparatus is provided with a trimming function to erase unnecessary image portions of the images, a masking function to prevent the shaded portions from being recorded on the paper, and an image shift function to adjust the synthesizing positions of the images on the recording paper for every image.

Abstract: An image forming device such as a copier has separate upper, middle and lower units which are mutually openable. The axes of rotation around which the upper unit can rotate with respect to the middle unit and the middle unit with respect to the lower unit are symmetrically disposed and engaging and locking mechanisms are provided such that when one of the pairs of mutually openable units is opened, the other pair is prevented from opening. Thus, the overall equalibrium of the device is not lost even if both pairs of units are opened.

Abstract: A fixing device for image forming apparatus utilizing image forming media of a plurality of different widths, comprises a core roller and a supporting roller parallel to and in contact with the core roller to supports the selected one of the image forming media with the toner image thereon and transporting the selected image forming medium, an electrically resistive heat layer on the core roller and a plurality of power supply electrodes for supplying power to at least two portions of the electrically resistive heat layer having sizes corresponding to the widths of at least two of the image forming media.

Abstract: In a liquid toner xerographic system, a sheet of matted polyester is held against the back of the selenium xerographic plate as it passes the transfer station to absorb the toner on the back and leading and trailing edges of the plate. The material is supplied by supply and take up rolls and is advanced a predetermined amount for each passage of the plate. The material is located above the transfer station to clean the transfer wiper in the absence of a plate.

Abstract: A plurality of photosensitive drums are arranged such that color-separated light images of an original document are formed respectively thereon. The photosensitive drums are independently driven under equal conditions by a single drive source for preventing image colors, i.e., image positions, from being shifted out of registry on an image transfer sheet.

Abstract: An apparatus in which particles are moved from one end of a duct to the other end thereof. The particles in the duct are fluidized. A pressure differential is generated which moves the fluidized particles in the duct from one end of the duct to the other end thereof. When the particles pack and cake together, the apparatus automatically moves the toner particles away from the region of the packed and caked toner particles to relieve this condition.

Abstract: An electrostatographic machine has both (1) feedback means for adjusting process control parameters in response to long term variations in the electrostatographic process and (2) feedforward means for adjusting process control parameters in response to short term variations in the electrostatographic process without negating the effect of the feedback means. The average of a predetermined number of sensed recording member reference voltages associated with image areas is compared to the reference voltage output of a single image area, producing a difference signal for controlling at least one process control parameter for the single image area, whereby the control of the parameter is responsive to short term variations in the output signal and is substantially non-responsive to long term variations in the output signal.

Abstract: An improved copying apparatus for copying by shifting images by a desired distance, and also for copying the central portion of a copy paper sheet according to copying factors such as the copy paper sheet sizes, original document sizes and copying magnifications.

Abstract: A copying machine exposure adjustment device, including an operation panel that converts user operations into digital signals, a digital operation circuit that processes operational data from the operation panel and computes exposure data, a D/A converter that converts exposure data sequentially transmitted from the digital operation circuit into analog exposure data, a copy-lamp control circuit that adjusts the light volume of a copying lamp in response to the exposure data from the D/A converter, an image density circuit that detects light reflected from the original document, and a data correction circuit that corrects the exposure data from the D/A converter in response to the image density data from the image density detector circuit while the automatic exposure mode is in operation.

Abstract: In a toner concentration detecting device wherein developer is carried by a roll from a developer flowpath to a detection station for optical detection thereof, a restriction element is provided adjacent the roll between the developer flowpath and detection station to limit the thickness of the developer adhered to the roll. A scraper is provided downstream of the detection station for cleaning the roll, and the roll itself is covered with a non-magnetic material to provide a substantially smooth outer surface.

Abstract: A method of and an apparatus for producing duplicates of a document in color wherein a plurality of photosensitive members in drum form are rotated in the same direction and exposed to respective color-separated optical images of the document through respective arrays of gradient-index rod lenses to form electrostatic latent images on the photosensitive members while the document is supported on a document support member and moved in the same direction as the rotation of the photosensitive drums. The electrostatic latent images on the photosensitive members are developed in different colors into visible images of different colors which are printed by transfer-printing on a sheet of support material on a transfer-printing belt moved in a direction opposite the direction of movement of the document support member for light exposure of the photosensitive members.

Abstract: An electrophotographic printing machine utilizing an optical illumination and scanning system which, besides performing the conventional document reproducing function, is adapted to operate in a machine test mode. In the test mode, target strips of varying density affixed to the bottom of a platen are projected as test patch images onto the surface of a photoreceptor. The voltage levels of these patches are then measured and used to adjust variable parameters to maintain optimum operation.The optical system, when operating in the test mode, sequentially and selectively illuminates various of the test patches while control means selectively varies the illumination levels.

Abstract: An image-forming apparatus is disclosed which is able to form an image while blanking any unnecessary image portion or extracting any desired image portion at one's will. To this end, the apparatus includes a plurality of light exposing means, an image area setting means and control means. Said control means selectively renders said individual light exposing means operative or inoperative according to the selected image area by said image area setting means.

Abstract: A variable magnification optical apparatus for projecting an image at a first plane onto a second plane includes an optical system for forming an image of the first plane on the second plane, a first mirror disposed between the image-forming optical system and the first plane and a second mirror disposed between the image-forming optical system and the second plane. When the magnification is changed, the first mirror is rotated by a determined angle of .theta. and the second mirror is moved in a determined direction while rotating also by the same angle .theta.. The image-forming optical system is moved in the direction along its optical axis and is rotated by an angle two times larger than the rotation angle .theta. of the first mirror at the same time.