摘要:
A double-sided printing apparatus using a double sided printing with one plate cylinder and one pressing means system, that is capable of carrying out double-sided printing simply and at low cost, with little deviation in the position of the printed image and with satisfactory resist. Printed matter with little deviation of the image position with respect to the sheet position and with good resist can be obtained, by eliminating delay in feeding sheets due to slippage between roller and press roller by operating the transport belt on the upstream side, and so on, and by eliminating resistance during sheet transportation due to contact with the guide member provided along the circumferential surface of the press roller, when pressing sheets against the press roller with a roller or the like, and transporting the sheets along the guide member or the like provided along the peripheral surface of the press roller. After the resist roller has eliminated the contact between the sheet and the stopper, the transport belt starts to be driven. If the printing speed is low, this timing is taken as the timing that the resist roller contacts the press roller. For both low speeds and high speeds, this may be after passage of a predetermined period of time from the operation command signal for the resist roller.
摘要:
A stencil material roll includes stencil material in a continuous length rolled around a core tube and a memory IC which stores predetermined information. The memory IC is mounted on a wall portion which forms a part of the core tube or on a wall portion fixed to the core tube, and an easy-to-cut portion is provided on the wall portion to surround the portion where the memory IC is mounted.
摘要:
A stencil printer of the present invention includes a print drum around which perforated part of a stencil or master is to be wrapped. A master making section make a master and includes a cutter for cutting the stencil paid out from a roll. A master discharging section removes the master wrapped around the print drum and then discharges it. A deciding device determines, on the turn-on of a power supply, whether or not the power supply has been turned off during an interval between the time when the stencil paid out from the roll starts being perforated and the time when the cutter cuts the stencil. When the deciding device determines that the power supply has been turned off during the above interval, the master discharging section discharges the master present on the print drum.
摘要:
A method for predicting printing density for use in a stencil printing in which an ink is transferred from a rotated printing drum to a printing sheet through a perforated stencil, by pressing the printing sheet and the printing drum against each other, is provided. The method comprises (a) a first step of measuring printing densities (OD) on at least two copies of print at corresponding printed portions thereof, the copies of print being obtained under different conditions of F/f, in which F is a pressing force at which the printing sheet is pressed to the drum and f is a rotation speed of the drum, (b) a second step of statistically processing the printing densities measured in the first step to obtain a function of printing density and F/f value, and (c) a third step of calculating a printing density at a desired pressing force and a desired rotation speed based on the function obtained in the second step. The function may be OD=V×{square root over ( )}(F/f)+W, in which V and W means constants that may be obtained by least-squares method.
摘要:
A lithographic ink and moisture control system is provided for maintaining copy quality over a wide range of operating and environmental conditions without special operator assistance. The control system, among other things, adjusts the ink and moisture feed rates upon machine start up to compensate for moisture evaporated from the system during shutdown.
摘要:
An automated offset lithographic duplicating machine permits to automatically mount a master or lithographic plate on a master cylinder, to apply ink repellent etching solution to the mounted master or lithographic plate in a time predetermined by the operator, and to perform a number of sequential duplicating steps of a duplicating cycle. The washing of a blanket cylinder, constituting the final step of the duplicating cycle of a lithographic plate, is performed in a time predetermined by the operator before the cylinder automatically stops. The number of copies to be duplicated for each lithographic plate is indicated by an indicator after marks on the lithographic plate, for indicating the number of copies to be duplicated, are read by a device provided in the machine. When the number of copies indicated by the indicator has been duplicated, washing of the blanket cylinder is automatically initiated.
摘要:
A method and an apparatus obviating the problem of how to supply an optimum quantity of ink to a master plate to be duplicated by offset duplicating machines. The method consists in automatically controlling the quantity of ink supplied to the master plate by measuring the ratio of the area of image regions of the plate to the whole area of the plate or the image area ratio or by reading the code marks superposed on the plate for indicating the image area ratio. Measurement of the image area ratio is carried out by scanning the image surface of the plate by means of a scanning head.
摘要:
A plurality of control levers are pivotally mounted, on a common shaft, extending transversely of the path of movement of an original for deflection by the leading edge thereof, Each lever has a respective electric switch associated therewith for actuation responsive to deflection of the lever. The leading edge of each original is formed with one or more forwardly opening recesses, representing a binary code, with the recesses being arranged in groups, each group corresponding, for example, to units, ten, hundreds, etc. The recesses effect delayed deflection of the correspondingly located levers and corresponding delayed actuation of the associated electric switches. After each lever not opposite a recess has been deflected by the leading edge of an original, a transverse rod is engaged beneath hooked end of the deflected levers and a frame mounting both the deflected levers and the non-deflected levers is pivoted to move all of the levers out of the path of movement of the original. Only certain electric switches are actuated in accordance with those levers corresponding to the recesses in the leading edge of the original. The switches may be connected to a value storage, or the switches and the actuating levers therefor may constitute a value storage and be used in a coincidence circuit arrangement with corresponding switches actuated by a mechanical counter which counts the number of copies. When the number of copies reproduced is equal to the number set in the value storage, the reproduction is interrupted and all of the levers are returned to their initial positions. The forwardly opening recesses may be Ushaped, V-shaped, or rectangular.
摘要:
The printing drum of a duplicating machine has a cavity in which an ordinal set of stamping wheels is mounted for making additional imprints on a copy sheet. A casing, which supports a set of manual setting levers, has an operative position in which the setting levers are connected with the stamping wheels, respectively, by meshing gears in the cavity so that the small stamping wheels can be set by the conveniently large setting levers. The casing with the setting levers can be retracted from the printing drum so that the gears are separated, and printing operations can be carried out by the printing drum without obstruction by the casing and setting levers.
摘要:
A duplicating machine having a stencil carrier movable to repeatedly carry a stencil into and out of a printing position and a counter operatively coupled to the carrier, has a stencil spoiler movable into an operative position to engage and spoil a stencil on the carrier, and a retainer controllable by the counter to hold the spoiler inoperative until the counter responds to the completion of a predetermined number of operative movements by the stencil carrier.