Abstract: A device for determining an amount of ink in an inking arrangement of a printing machine, which has a conversion unit for determining independently a conversion function with respect to each divided blade piece of an ink fountain and for calculating an average value of rotational angle or speed of an ink fountain roller. This construction can cope with a weary of each blade piece and the outer surface of the ink fountain roller.

Abstract: An automatic sheet stack loading mechanism of a paper sheet feeding apparatus has a main lift for supporting a stack of sheets to be fed thereon. The main lift is incrementally moved upwardly to place the uppermost sheet of the stack at a predetermined height position with respect to a sheet separator disposed over the stack and operating to separate the sheets one by one from the stack. When the stack of sheets is consumed considerably, parallel horizontal spits are inserted under the stack from both transverse sides of the stack thereby to support the load of the stack and to enable the main lift to be lowered to receive a new stack of the sheets. The insertion of the spits in the transverse direction of the stack is advantageous in that the central portion of the sheets of the stack along the direction of feed of the sheets is maintained at constant height irrespective of downward deflection of the spits so that adjustment in position of the sheet separator is not required.

Abstract: A method and device for measuring the quantity of water dampening the face of an offset printing plate in which a light beam is made incident at a suitable angle to the face of the printing plate and the light beam directly reflected from the plate at the same angle with the angle of incidence as well as the light beam diffuse-reflected in the direction normal to the face of the printing plate are independently detected so that an image area and a non-image area on the face of the plate are detected in response to the diffuse-reflected light beam; and the variations in level of the directly reflected light beam is calibrated in response to the diffuse-reflected light beam.

Abstract: The invention discloses a device for measuring the concentration of alcohol contained in the dampening water used in printing. Part of the dampening water pumped up from a dampening water tank (1) and delivered to a water fountain (3) is sampled through a bypass passage and the dampening water is returned to the dampening water tank (1) after the measurement of the concentration of the sampled dampening water. A measuring unit (8) for detecting the concentration of alcohol has a shielding plate (13) disposed adjacent to the dampening water inlet so that the disturbance of the surface of the dampening water introduced into the measuring unit is prevented. The dampening water discharge outlet consists of a pipe whose upper end is in coplanar relationship with a predetermined surface level of the aqueous solution in the measuring unit so that the excessive dampening water overflows into the pipe (10) to return to the dampening water tank.

Abstract: A method for registering in an offset printing press comprises: mounting a printing plate on a shiftable table of a plate bending machine; detecting datum fine lines on said plate, by means of optical sensors; shifting the shiftable table so that said datum fine lines are placed at specific positions; inscribing, by means of a register mark inscribing device, register marks for carrying out automatic registering while, at the same time, bending the lateral edges of the printing plate; thereafter mounting the printing plate on a corresponding plate cylinder of a printing press; and carrying out automatic registering. The above plate bending machine comprises plate bending mechanisms, a shiftable table for holding the printing plate, optical detection sensors disposed above the shiftable table and operating to detect datum lines on the plate and thereby to generate signals for the movement of the table and register mark inscribing devices for automatic registering on a plate cylinder of the printing press.

Abstract: A method for forming or marking register marks used for the automatic registration between a plurality of printing plates in a printing press. A register mark forming or marking device is mounted on a printing frame of an automatic composer so that a register mark can be formed or marked on a printing plate simultaneously with the printing of a film original over the printing plate. Misalignment between the thus formed or marked register marks and patterns or images can be eliminated.

Abstract: A method for registering in an offset printing press comprises: mounting a printing plate on a shiftable table of a plate bending machine; detecting datum fine lines on said plate, by means of optical sensors; shifting the shiftable table so that said datum fine lines are placed at specific positions; inscribing, by means of a register mark inscribing device, register marks for carrying out automatic registering while, at the same time, bending the lateral edges of the printing plate; thereafter mounting the printing plate on a corresponding plate cylinder of a printing press; and carrying out automatic registering. The above plate bending machine comprises plate bending mechanisms, a shiftable table for holding the printing plate, optical detection sensors disposed above the shiftable table and operating to detect datum lines on the plate and thereby to generate signals for the movement of the table and register mark inscribing devices for automatic registering on a plate cylinder of the printing press.