JPH10138448A - Method and structure for holding doctor blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a uniform film by adequately and uniformly squeezing a liquid on a plate or roll for printing by a method wherein a whole plane part of a doctor blade is uniformly pressed and held by an inclined face in a wedge structure such that a linearity in a tip of the doctor blade is not disturbed. SOLUTION: A doctor blade 10 is disposed to a lower side 11b of a V-shaped inner section of a receiving frame 11 and a pressing body 12 is inserted to the V-shaped inner section of the receiving frame 11 such that an inclination face 12a of a lower side of the pressing body 12 contacts the doctor blade 10. A bolt 13 is screwed into a female screw 11a of the receiving frame 11 from a right side face 12c of the pressing body 12 to a hole 12d in the condition that the doctor blade 10 and pressing body 12 are in contact with each other and the doctor blade 10 is supported by the lower side 11b of the receiving frame 11 and the inclination face 12a of the lower side of the pressing body 12. As a result, a component force is generated on the inclination face 12a and the whole part of the doctor blade 10 is roughly uniformly held by a surface pressure of the wedge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a doctor used for scraping a liquid or the like (including ink; hereinafter, referred to as a liquid) on a printing plate or roll for offset printing or the like to form a uniform film. The present invention relates to a holding method for holding a blade and a holding mechanism for holding the doctor blade.

[0002]

2. Description of the Related Art In recent years, printing machines have been used in many fields because of their low cost and high speed. Among them, the printing plate or roll surface provided in the printing machine is used. A doctor blade is used to form a uniform film of the liquid.

Hereinafter, a conventional doctor blade holding mechanism will be described with reference to the drawings.

FIG. 5 is an explanatory view of a schematic configuration of a printing machine using a conventional doctor blade, wherein 1 is a printing roller,
2 is a dispenser for dropping the liquid F on the printing roller 1, and 4 is a dispenser for dropping the liquid F on the printing roller 1.
A doctor blade 5 for scraping off and forming a uniform film on the surface of the printing roller 1 is a holder for holding the doctor blade 4.

FIGS. 3 and 4 show a conventional mechanism for holding the doctor blade. FIG. 3 is a side sectional view, and FIG. 4 is an exploded perspective view. The doctor blade 4 and the flat plate 6 in this joined state are inserted into the gap 3a of the holding block 3 having a U-shaped cross section. Then, the holding block 3
A plurality of bolts 8 are screwed in from a female thread portion 7 formed on the upper side of the doctor blade, and the bolts 8 are tightened from above the joint surface between the doctor blade 4 and the flat plate 6. And is held in the holding block 3 via.

[0006]

However, the conventional doctor blade holding mechanism is a method and structure for holding the doctor blade 4 by pressing the bolt 8 from a direction perpendicular to the upper plane of the flat plate 6. ,
There is a difference in the holding force with respect to the doctor blade 4 between the portion immediately below the bolt 8 and the portion other than the bolt 8, and therefore, the doctor blade 4 is likely to be non-uniformly bent, and when this bending occurs, the straight line of the cutting edge 4a of the doctor blade 4 is straightened. However, it is not easy to form a good uniform film surface on the surface of the printing roller 1.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a doctor blade holding method and a doctor blade holding mechanism capable of solving the above-mentioned conventional problems and forming a uniform film surface.

[0008]

In order to achieve the above object, a method and a mechanism for holding a doctor blade according to the present invention are provided so that the entire flat portion of the doctor blade can be maintained without impairing the linearity of the blade edge of the doctor blade. A method and mechanism for uniformly pressing and holding by an inclined surface in a wedge structure, wherein the blade can be held substantially uniformly by a wedge over the entire surface of the doctor blade, and the bending of the cutting edge resulting from unevenness of the holding of the doctor blade. And the loss of linearity can be prevented, so that the liquid on the roll or plate can be scraped off satisfactorily, and a uniform film can be formed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view of a doctor blade holding mechanism for explaining an embodiment of the present invention. FIG. 2 is an exploded perspective view of the doctor blade holding mechanism of FIG.
10 is a thin plate for scraping off the liquid with a cutting edge 10a in order to uniformly form a film of liquid such as ink on the surface of a printing plate or a roller for offset printing or the like as described with reference to FIG. A doctor blade 11 made of resin or metal has a substantially V-shaped cross section, and a receiving frame body having a plurality of internal threads 11a formed on an inner bottom surface, and an outer surface 12 conforming to the V shape of the receiving frame body 11. An inclined surface 12a is formed up and down in the shape, the outer surface of the right side 12c is wider than the left side 12b, and a through hole 12d penetrating between the left side 12b and the right side 12c is formed. The holding body 13 having a wedge-shaped cross section is a bolt as a pressing member that is screwed into the female screw 11a of the receiving frame 11 from the right side surface 12c of the holding body 12 through the through hole 12d.

Next, a method for holding the doctor blade by the holding mechanism having the above-described structure will be described.

The doctor blade 10 is placed on the lower side 11b inside the V-shape of the receiving frame 11, and the pressing body 12 is further joined to the doctor blade 10 such that the lower inclined surface 12a of the pressing body 12 is joined. , Into the V-shape of the receiving frame 11. In a state where the doctor blade 10 and the holding body 12 are joined, the bolt 13 is screwed into the female screw 11a of the receiving frame 11 through the through hole 12d from the right side surface 12c of the holding body 12, and the doctor blade 10 is inserted into the receiving frame. It is held so as to be clamped by the lower side 11b inside the body 11 and the lower inclined surface 12a of the presser body 12.

By holding the doctor blade 10 in this manner, the doctor blade 10 is perpendicular to the plane portion of the doctor blade 10 in a state in which the doctor blade 10 is flush with the inclined surface 12a of the wedge-shaped pressing body 12. Not to be tightened by bolts 13 from the direction a.
Due to the generation of the component force at 12a, the doctor blade 10 is held substantially uniformly by the surface pressure of the wedge over the entire surface.

As described above, since the entire doctor blade 10 can be held uniformly, distortion and bending of the doctor blade 10 caused by uneven holding can be suppressed. Since distortion and waving can be prevented from occurring, the linearity of the cutting edge 10a is not impaired, so that a film of liquid such as ink is uniformly applied to the surface of a printing plate or a roller. Can be formed.

[0015]

As described above, the doctor blade holding method and the doctor blade holding mechanism of the present invention can uniformly hold the entire doctor blade by using a wedge structure. The linearity of the cutting edge can be prevented from being impaired, and the liquid on the printing plate or roll can be satisfactorily and uniformly scraped to form a uniform film.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a doctor blade holding mechanism for explaining an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a doctor blade holding mechanism of FIG. 1;

FIG. 3 is a side sectional view of a conventional doctor blade holding mechanism.

FIG. 4 is an exploded perspective view of a doctor blade holding mechanism of FIG. 3;

FIG. 5 is an explanatory diagram of a schematic configuration of a printing press using a conventional doctor blade.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Printing roller, 2 ... Dispenser, 10 ... Doctor blade, 11 ... Receiving frame, 12 ... Wedge-shaped pressing body, 12a ... Inclined surface, 13 ... Bolt, F ... Liquid.

Claims (2)

[Claims] 1. A printing plate for printing such as offset printing or a film of a printing substance such as ink is uniformly formed on the surface of a roller. In the method for holding the doctor blade, the entire flat portion of the doctor blade is uniformly pressed and held by the inclined surface of the wedge structure so as not to impair the linearity of the blade of the doctor blade. Characteristic method of holding a doctor blade. 2. A doctor blade for scraping off the printing substance with a cutting edge in order to uniformly form a film of a printing substance such as ink on the surface of a printing plate or a roller for offset printing or the like. A wedge having an inclined surface slidably in contact with the entire flat surface of a doctor blade made of a thin plate of resin or metal, and the inclined surface of the wedge causes the flat surface of the doctor blade to move the blade edge of the doctor blade. And a pressing member that presses the wedge from a direction not orthogonal to the flat portion of the doctor blade and is fixed to the receiving frame. Characterized in that the blade is configured to be held by the receiving frame so as not to impair the linearity of the cutting edge. Doctor blade holding mechanism.