MAIN BODY OF A DOCTOR BLADE CHAMBER, DOCTOR BLADE CHAMBER THEREOF AND METHODS OF MANUFACTURING SAME

Abstract

A main body of doctor blade chambers including a first portion configured to hold a first doctor blade, a second portion configured to hold a second doctor blade, a third portion connecting the first portion and the second portion, a cavity intended to receive ink and defined at least by the first portion, the second portion and the third portion, characterized in that the main body is a single closed hollow profile extending along a longitudinal main axis X-X, the main body being made of pultruded composite material.

Claims

1. A main body of a doctor blade chamber comprising a first portion configured to hold a first doctor blade, a second portion configured to hold a second doctor blade, a third portion connecting the first portion and the second portion, a cavity intended to receive ink and delimited at least by the first portion, the second portion and the third portion, wherein the main body is a single hollow closed profile extending according to a longitudinal main axis X-X, the main body being made of a pultruded composite material.

2. The main body according to claim 1, wherein the composite material is a pultruded composite carbon.

3. The main body according to claim 1, wherein the composite material in which the main body is formed comprises a fiber volume strictly larger than 60% of the volume of the composite.

4. The main body according to claim 3, wherein the fiber volume is between 61% and 70% of the volume of the composite.

5. The main body according to claim 1, comprising a non-woven fabric arranged on the surface of the main body, the non-woven fabric being integrated into the mass of the main body.

6. The main body according to claim 1, wherein the composite material in which the main body is made by pultrusion with a fiber rate strictly higher than 60%, has a performance ratio higher than 112% compared to the performance ratio of the same composite material in low-pressure resin injection molding.

7. A doctor blade chamber comprising: a main body according to claim 1, a first doctor blade mounted on a first portion of the main body, a second doctor blade mounted on a second portion of the main body, opposite the first doctor blade.

8. The doctor blade chamber according to claim 7, comprising a pressurized water channel, arranged in the main body.

9. The doctor blade chamber according to claim 8, wherein the water channel comprises at least one washing nozzle opening into the water channel and protruding from the water channel through the third portion of the main body.

10. The doctor blade chamber according to claim 8, wherein the water channel is positioned in a hollow of the profile of the main body, a first side of the water channel being arranged against a first internal face of the main body and a second side of the water channel, opposite to the first side of the water channel being arranged against a second internal face of the main body.

11. The doctor blade chamber according to claim 8, wherein the water channel is a profile made of a composite material comprising carbon.

12. A method for manufacturing a main body of a doctor blade chamber, the manufacturing method comprising at least one step of pultruding a main body according to claim 1.

13. A method for manufacturing a doctor blade chamber according to claim 7, the manufacturing method comprising at least one step of obtaining a main body according to the manufacturing method comprising at least one step of pultruding a main body of a doctor blade chamber comprising a first portion configured to hold a first doctor blade, a second portion configured to hold a second doctor blade, a third portion connecting the first portion and the second portion, a cavity intended to receive ink and delimited at least by the first portion, the second portion and the third portion, wherein the main body is a single hollow closed profile extending according to a longitudinal main axis X-X, the main body being made of a pultruded composite material.

14. The manufacturing method according to claim 13, comprising at least one additional step of inserting and assembling a water channel shaped to form a water network in the main body of the doctor blade chamber.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0055] The invention will be better understood, thanks to the description hereinafter, which relates to an embodiment according to the present invention, provided as a non-limiting example and explained with reference to the appended schematic figures, in which identical reference numerals correspond to structurally and/or functionally identical or similar elements. The appended schematic figures are listed hereinbelow:

[0056] FIG. 1 is a schematic illustration of a flexographic printing unit comprising a conventional doctor blade chamber,

[0057] FIG. 2 is a perspective view of the doctor blade chamber according to the invention,

[0058] FIG. 3 is a perspective view of the main body of the doctor blade chamber according to the invention and as illustrated in FIG. 2,

[0059] FIG. 4 is a partial perspective view of the doctor blade chamber according to the invention and as illustrated in FIGS. 2 and 3,

[0060] FIG. 5 is a detail view according to box A of FIG. 4,

[0061] FIG. 6 is a partial detail view of the doctor blade chamber according to the invention and as illustrated in FIGS. 2 to 5,

[0062] FIG. 7 is a side view of the main body of the doctor blade chamber according to the invention.

DETAILED DESCRIPTION OF THE FIGURES

[0063] As described above to illustrate the context of the invention, a printing unit 100 comprises: [0064] a plate cylinder 104 configured to support a plate or printing form 108, [0065] a screened or anilox roller 103, having over its surface a plurality of cells intended to collect ink in an amount controlled by the volume of the cells, the screened roller 103 being configured to transfer the ink onto the plate 108, [0066] a doctor blade chamber 101, configured to fill the cells of the screened roller 103, [0067] a pump 102, ensuring the ink supply from the ink tank 107 to the doctor blade chamber 101, and [0068] a back pressure cylinder 105 holding the support being printed 106 against the plate cylinder 104, and thus against the plate 108.

[0069] The doctor blade chamber of the invention is designated by the reference numeral 1 and is illustrated in detail with reference to FIGS. 2 to 7.

[0070] The doctor blade chamber 1 according to the invention comprises a main body 2 made in one-piece which is a closed hollow profile, as illustrated in particular in FIG. 3. The main body 2 has a constant and uniform thickness in all points of the section and over the entire length of the profile, as illustrated in particular in FIGS. 3, 6 and 7. The main body 2 extends according to a longitudinal main axis X-X as illustrated in particular in FIGS. 2 and 3. Furthermore, the main body 2 is made of pultruded composite carbon.

[0071] As shown in FIG. 3, the main body 2 has a first portion 2a, a second portion 2b and a third portion 2c. The third portion 2c connects the first portion 2a and the second portion 2b, the third portion 2c being shaped and intended to partially receive a screened roller therewithin. As shown in FIG. 3, the third portion 2c is set back with respect to the first portion 2a and to the second portion 2b of the main body 2, so that between the first portion and the second portion, a cavity 2e is formed.

[0072] Furthermore, the main body 2 has a first face 2.1 intended to be opposite the screened roller and a second face 2.2 opposite to the first face 2.1 as illustrated in FIG. 3.

[0073] According to the invention, the doctor blade chamber 1 further comprises a first doctor blade 3, the first doctor blade 3 being mounted on the first portion 2a of the main body 2 by means of a first doctor blade flange 5 as represented in FIGS. 2 and 7. Each flange is held by a fastening system 7 consisting of the cooperation of a screw or a pin, shown in FIG. 2 with an insert 7a and shown in FIGS. 4 and 7 for example. In addition, the doctor blade chamber 1 comprises a second doctor blade 4, the second doctor blade 4 being mounted on the second portion 2b of the main body 2, opposite the first doctor blade 3, by means of a second doctor blade flange 6 as represented in FIGS. 2 and 7. In the example illustrated in FIGS. 2 and 7, the first doctor blade 3 and the second doctor blade 4 partly close the cavity 2e formed by the first 2a, second 2b and third 2c portions of the main body 2.

[0074] According to the invention, the main body 2 comprises a non-woven fabric 16 arranged on the surface of the main body 2 as represented in solid line in FIG. 7. In the example illustrated in FIG. 7, the non-woven fabric 16 is represented as covering the entire surface of the main body 2 but, in variants which are not represented, the non-woven fabric could cover only one portion of the main body 2 for example only the first face 2.1 or only the second face 2.2 or only one of the portions 2a, 2b, 2c of the main body 2.

[0075] According to the invention, and as represented in particular in FIG. 7, the doctor blade chamber 1 comprises a pressurized water channel 11, arranged in the main body 2 and more specifically in the hollow 2d of the profile of the main body 2 at the level of the third portion 2c. The water channel 11 advantageously extends over the entire length of the main body 2. Advantageously, the water channel 11 is a profile with a substantially rectangular cross-section.

[0076] As shown in FIG. 7, a first side 2.3 of the water channel 11 is arranged against the first internal face 2.1 of the main body 2 and a second side 2.4 of the water channel 11, opposite to the first side of the channel of water 11 is arranged against the second internal face 2.2 of the main body 2.

[0077] According to the invention, the water channel 11 comprises at least one plurality of washing nozzles 10 opening into the water channel 11 and protruding from the water channel 11 through the third portion 2c of the body main 2 as illustrated in FIGS. 2 and 7. In the example illustrated in FIG. 7, the water channel 11 is glued in the main body 2 by means of an expansive glue 17 for sealing. Advantageously, the washing nozzles 10 of the plurality are evenly spaced all along the water channel 11. As shown in FIG. 7, the washing nozzles 10 open into the cavity 2e formed by the first, second and third portions 2a, 2b, 2c of the main body 2.

[0078] Moreover, the doctor blade chamber 1 according to the invention comprises an ink channel 12, extending all along the main body 2 and arranged in the hollow 2d of the profile of the main body 2. The ink channel 12 comprises at least one ink outlet 13 illustrated in FIG. 6 opening into the ink channel 12 and protruding from the ink channel 12 through the third portion 2c of the main body 2. Advantageously, the ink channel 12 is a profile with a substantially circular cross-section.

[0079] According to the invention, the doctor blade chamber comprises a first end part 8a and a second end part 8b, each end part 8a, 8b being arranged at one end of the main body 2 of the doctor blade chamber 1. As shown in particular in FIG. 4, a portion of the first end part 8a is inserted into a first end of the profile of the main body 2 and a portion of the second end part 8b is inserted into a second end of the profile of the main body 2.

[0080] Advantageously, the first end part 8a has at least one orifice shaped so as to house a pipe 9a connecting the water channel 11 to a water tank and a second orifice shaped so as to house a pipe 9b connecting the ink channel 12 to an ink tank as illustrated in FIGS. 7 and 2.

[0081] Moreover, the doctor blade chamber 1 comprises a supporting element 14 illustrated in FIGS. 2 to 5 and 7 arranged on the second face 2.2 of the main body 2 and configured to strengthen the doctor blade chamber 1. In addition, the doctor blade chamber 1 comprises a hook 15 intended to enable the hooking of the doctor blade chamber system 1.

[0082] Of course, the invention is not limited to the embodiment described and represented in the appended figures. Modifications are still possible, in particular with regards to the constitution of the various elements or by substitution with technical equivalents, yet without departing from the scope of the invention.