SU1313730A1 - Plate cylinder - Google Patents

Abstract

The invention relates to the printing industry, in particular, to devices for etching intaglio printing forms and devices for producing pigment-gelatin copies. Plate cylinder includes a housing 1 with an annular chamber 2, on the inner surface 3 of which is made of longitudinal and transverse 5 grooves. There are support washers 6 with through holes 7, ends 8 and trunnions 9. By means of fitting 10, chamber 2 is connected to a vacuum source, then to a distilled water supply system, and then sealed. If external factors appear that affect the temperature of the working surface of the body 1 of the plate cylinder, a local temperature change and boiling occur if the surface is more warm and the vapor condenses on the cooled surface. 1 hp f-ly, 2 ill. S fae, 7 (L with CO with

Description

The invention ranges from printing to printing, in particular to devices for etching forms of intaglio printing and devices for generating nigment-gelatin copies, also intended for etching forms of intaglio printing.

The purpose of ..-, the invention is to increase the quality of the appearance of copies and the etching of form-depth printing.

Fig. 1 shows a forme cylinder; Bb view; la fig. 2 shows a section A -A in FIG. one.

The plate cylinder has a housing 1 with a chamber 2, the inner surface 3 of which contains a longitudinal 4 and transverse grooves 5, support washers 6 with through holes 7, ends 8 and pins 9. At the end 8 there is a vacuum fitting 10, CBH3iji 2 with a vacuum source (not shown}, and then eliminating the filling of chamber 2 with distilled water from its feed system.

On the inner surface 3 of the chamber 2 along its length, longitudinal 4 and transverse 5 grooves are made. Their depth is 1/5 of the wall of the casing 1. The width of the grooves and the distance between them is 4--5 mm. This embodiment of the inner surface 3 provides a viscous adhesion and an effective heat and mass transfer between the coolant and the surface of both the fixed and rotating n, i-lipdra. The selected width between the grooves (4-, 5 mm) ensures the absence of shadow temperature zones on the outer working surface of the plate cylinder.

The thrust washers 6 are made with through holes 7 in order to create in the central zone an annular gauge 2 and in two peripheral ones, i.e. between the supporting piping 6 and the ends of 8, the same pressure and the free movement of gas-liquid flows. This provides temperature control over the entire outer working surface of the plate cylinder. The inner surface 3 is electroplated with a protective layer of a chromium type metal with a coating thickness of 1-3 µm to prevent corrosion.

By means of fitting 10 and a vacuum pump, the closed volume of chamber 2 is vacated and then filled with distilled water with a mass continuity of 0.00150, 003%. After which the plate cylinder is sealed. The percentage of mass continuity of distilled water is determined on the basis of obtaining saturated steam in the form; cylinder and provide there for evaporation and condensation at normal ambient temperature.

Form qi; 1indr works as follows.

0 Distilled water in a rarefied state boils at low pressure in the body 1 of the plate cylinder and is in it as a mixture of water and steam. When external disturbing factors appear that affect the temperature of the working surface of the cylinder body 1 and cause local temperature changes, water near its warmer surface boils rapidly, evaporates and in the form of steam is quickly transferred to more

0 cold surface areas 3. The steam is in contact with the cold surface area 3 and is co-depsified there. This produces heat, the amount of which is equal to the heat absorbed during vaporization, i.e. heat; 1 o is spent on heating the fluid, and on compensating its cooling. As a result, the temperature of the working surface of the body 1 of the plate cylinder is effectively automatically adjusted according to the criterion of its stabilized linearization on all

., working areas of the cylinder surface. Thus, the maximum approximation of the actual gradation etching curve to the target is provided.

five

Claims (2)

1. A feed cylinder comprising a housing with a camera, support washers at its ends and pins, characterized in that, in order to improve the quality of the appearance of copies and etching of intaglio printing forms, the camera equipped with a vacuum source and distilled water supply system associated with it by means of a ptocera, the inner surface of the cages and has longitudinal and transverse grooves, and the support washers are made with through holes. 2. A cylinder according to claim 1, characterized in that the inner surface of the chamber is covered with a protective metal layer.