WO2013121565A1

WO2013121565A1 - Coating supplying printing device

Info

Publication number: WO2013121565A1
Application number: PCT/JP2012/053720
Authority: WO
Inventors: 繁中島
Original assignee: 株式会社伊万里鉄鋼センター
Priority date: 2012-02-16
Filing date: 2012-02-16
Publication date: 2013-08-22
Also published as: JPWO2013121565A1; JP5055512B1

Abstract

The present invention is capable of obtaining favorable durability and maintainability even with coatings that separate/precipitate easily or have the property of solidifying easily and eliminates the adverse effects on printing performance of the pulsation of the coating supplied by the circulating pump. The device is provided with: a tightly sealable coating tank (2) to which pressurized air is supplied; a coating circulation pathway (3) that is connected to the coating tank (2); a circulating pump (4) that is connected to the coating circulation pathway (3) and circulates the coating inside the coating tank (2) along the coating circulation path (3); a print head (6) that communicates with coating supply paths (5) that branch from the coating circulation path (3); and a control unit (7) that controls the printing action of the print head (6) and the action of the circulating pump (4). The control unit (7) stops the circulating pump (4) when the print head (6) is printing and operates the circulating pump (4) when printing by the print head (6) is stopped.

Description

Paint supply printing device

The present invention relates to a paint supply printing apparatus that supplies a print to a print head for printing.

The paint supply and application device that applies paint to the plate material, etc., connects the paint circulation path to the tank pressurization system that pressurizes the paint in the paint tank and supplies it to the application head via a supply tube, In general, a paint circulation system is known in which a paint supply path from the paint circulation path to the coating head is branched. In the paint circulation system, since the circulation pump is provided in the paint circulation path, unevenness in the injection amount of the coating head is likely to occur due to the pulsation pressure of the circulation pump. In order to solve this problem, an accumulator is provided on the downstream side of the circulation pump and on the upstream side of the branch to the print head to smooth the pulsation of the supplied paint (for example, see Patent Document 1 below).

JP 2006-61839 A

The above-mentioned paint circulation system paint supply and application equipment is easy to separate and settle, and when using a paint that is easy to solidify, the accumulator installed in the paint circulation path is likely to break down and is good. There is a problem that the durability and maintainability are not obtained.

On the other hand, the pulsation of the supply paint by the circulation pump is effective in eliminating the clogging in the supply tube or removing the paint adhered to the inner surface of the supply tube, but simply removing the accumulator, The spray amount of the coating head changes due to the pressure fluctuation of the supplied paint due to pulsation, which causes a problem that adversely affects the print performance of the print head.

The present invention relates to a paint supply printing apparatus that performs printing on a plate material or the like using paint, and an example of the problem is to cope with the above-described problem of the paint supply and application apparatus. That is, in a paint circulation type paint supply printing device, good durability and maintainability can be obtained even if the paint has the property of being easily separated / precipitated and solidified, and the pulsation of the supplied paint by the circulation pump It is an object of the present invention to prevent the printing performance from adversely affecting the printing performance.

In order to achieve such an object, a paint supply printing apparatus according to the present invention has at least the following configuration.
A sealable paint tank supplied with pressurized air, a paint circulation path connected to the paint tank, and a circulation connected to the paint circulation path for circulating the paint in the paint tank along the paint circulation path A pump, a print head that communicates with the paint supply path branched from the paint circulation path, and a control unit that controls a print operation of the print head and an operation of the circulation pump. A paint supply printing apparatus, wherein the circulation pump is stopped during a printing operation, and the circulation pump is operated when printing of the print head is stopped.

In the paint supply printing apparatus having such a feature, since the circulation pump is stopped during the printing operation of the print head, the pulsation of the supply paint by the circulation pump does not adversely affect the printing of the print head. In addition, when the print head stops printing, the circulation pump operates to circulate the paint along the paint circulation path, so that the proper fluidity of the paint can be maintained even when using paint that is easily separated / precipitated or solidified. However, the stirring state of the paint can be maintained. Furthermore, the clogging of the paint in the paint circulation path can be eliminated by the pulsation of the paint supplied by the circulation pump. As a result, it is possible to provide a paint supply / printing apparatus having good durability and maintainability even if it is a paint that is easily separated / precipitated and that is easily solidified.

It is explanatory drawing which showed the whole structure of the coating-material supply printing apparatus which concerns on one Embodiment of this invention. It is explanatory drawing which shows the basic control operation | movement of the control part of the coating material supply printing apparatus which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment of the present invention includes the contents shown in the drawings, but is not limited thereto. FIG. 1 is an explanatory diagram showing the overall configuration of a paint supply / printing apparatus according to an embodiment of the present invention.

The paint supply printing apparatus 1 includes a paint tank 2, a paint circulation path 3, a circulation pump 4, a print head 6, and a control unit 7. The paint tank 2 is provided with a lid portion 2A for charging the paint. The paint tank 2 can be filled with the lid portion 2A opened, and the paint tank 2 can be closed by closing the lid portion 2A. Can be sealed. In FIG. 1, the paint tank 2 is shown in a partially opened state in order to illustrate the internal structure, but is actually a cylindrical container.

In the illustrated example, a pressurized air supply pipe 2B communicating with the inside of the paint tank 2 is provided in the lid 2A, and a regulator 2C is provided in the pressurized air supply pipe 2B. The lid 2A is provided with a safety valve 2D for releasing the pressure in the paint tank 2. The pressurized air supply pipe 2B and the safety valve 2D can be provided on the side of the paint tank 2 other than the lid 2A. The inside of the paint tank 2 is in a positive pressure state by the pressurized air supplied through the pressurized air supply pipe 2 B during operation for supplying the paint to the print head 6.

The paint tank 2 is provided with a stirring means for stirring the paint that easily separates and settles. As an example of the stirring means, the paint tank 2 is made of a nonmagnetic material, and a non-contact stirrer 10 is provided in the paint tank 2 so that the non-contact stirrer 10 is driven to rotate in a non-contact manner. A non-contact stirring means in which the paint tank 2 is disposed is used. By using such a non-contact stirring means, the paint in the paint tank 2 can be stirred while the paint tank 2 is kept sealed.

The paint circulation path 3 can be constituted by a tube or a pipe having both ends connected to the paint tank 2, and the inlet end 3 A and the outlet end 3 B of the paint circulation path 3 are arranged in the paint tank 2. The inlet end 3 A and the outlet end 3 B are accommodated in one paint filter 12 in the paint tank 2. A circulation pump 4 is connected to the paint circulation path 3. The circulation pump 4 applies pressure for circulating the paint in the paint tank 2 along the paint circulation path 3. A diaphragm pump can be used as the circulation pump 4. By adopting a diaphragm pump using a material having high corrosion resistance, the corrosion resistance of the paint to the solvent can be enhanced.

The paint circulation path 3 is provided with one or a plurality of branch portions 3C, and the print head 6 communicates with the paint supply path 5 branched from the branch portions 3C. A plurality of paint supply paths 5 are branched from the branch portion 3C, and the tip of each paint supply path 5 is connected to the paint spray gun 6A of the print head 6. The paint spray gun 6A is controlled by the control unit 7 and can perform printing by applying a dot matrix paint on the print surface.

The control unit 7 controls the printing operation of the print head 6 and the operation of the circulation pump 4 by controlling the spraying operation of the paint spray gun 6A as described above. FIG. 2 is an explanatory diagram showing the basic control operation of the control unit 7. The control unit 7 stops (OFF) the circulation pump 4 when the print head 6 is printing (when the ejection operation is ON), and operates the circulation pump 4 when the print head 6 is stopped (when the ejection operation is OFF) ( ON).

The operation of such a paint supply / printing apparatus 1 will be described. First, the lid 2A of the paint tank 2 is opened, and the non-contact stirrer 10 and the paint are put into the paint tank 2, and then the magnetic drive unit 11 is operated to drive the non-contact stirrer 10 to rotate. Is confirmed to be sufficiently stirred, and the circulation pump 4 is operated.

After confirming that the paint is being stirred and circulated normally, the lid 2A is closed to ensure airtightness in the paint tank 2. Since the paint supply printing apparatus 1 according to the embodiment of the present invention employs the non-contact stirring means, the airtightness in the paint tank 2 can be improved, and the paint and air in the paint tank 2 come into contact with each other. Can be reduced as much as possible. As a result, the change in dilution concentration due to hardening or gelation of the paint or solvent volatilization due to stirring can be minimized. Moreover, since the washing | cleaning etc. are not required when removing the cover part 2A, the apparatus excellent in handling property and maintenance property can be obtained.

When the lid 2A is closed, pressurized air of a constant pressure is supplied from the pressurized air supply pipe 2B, and the inside of the paint tank 2 is maintained in a constant pressure state. A regulator 2C is provided in the pressurized air supply pipe 2B, and the pressure applied in the paint tank 2 is adjusted to be constant. Then, the print head 6 is operated by a control signal from the control unit 7 in a state where the paint in the paint tank 2 is sufficiently stirred and circulated.

An example of the operation of the print head 6 will be described. A plurality of paint spray guns 6A arranged in parallel in a direction intersecting the uniaxial direction is intermittently ejected with a controlled timing with respect to the print target surface moving in the uniaxial direction. Dot matrix-like printing is performed. At this time, the control unit 7 stops the operation of the circulation pump 4 during the printing operation of the print head 6 on which one character or a series of plural characters are printed. While the circulation pump 4 is stopped, the paint is supplied from the paint tank 2 to the print head 6 by the pressure of the pressurized air supplied into the paint tank 2. At this time, the pulsation of the supplied paint is stopped by stopping the circulation pump 4, and the paint is supplied to the print head 6 with a stable pressure of pressurized air, so that the paint injection from the paint injection gun 6A is performed with the set injection amount. Made.

On the other hand, when the printing operation of the print head 6 is not performed, the control unit 7 continues the operation of the circulation pump 4. Thereby, the pulsation of the supplied paint caused by the operation of the circulation pump 4 occurs in the paint circulation path 3, and the paint to be precipitated in the paint circulation path 3 or the circulation pump 4 can be effectively stirred and moved. .

In order to improve the maintainability of the paint supply printing apparatus 1, it is preferable that the circulation pump 4 and the magnetic drive unit 11 are continuously operated even when the print head 6 is not in operation such as at night or on holidays. In order to economically continue the operation of the circulation pump 4 and the magnetic drive unit 11 and to minimize the deterioration of the paint due to stirring, an intermittent drive means 20 for intermittently driving the circulation pump 4 and the magnetic drive unit 11 is provided. ing. The intermittent drive means 20 intermittently drives the circulation pump 4 and the magnetic drive unit 11 at set time intervals at night or holidays when the print head 6 is not in operation.

The circulation direction in the paint circulation path 3 by the circulation pump 4 is such that the primary side (suction side) of the circulation pump 4 is connected to the paint tank 2 side, and the secondary side (discharge side) is connected to the branch part 3C side. On the contrary, as shown in FIG. 1, the primary side (suction side) of the circulation pump 4 is connected to the branch portion 3C, and the secondary side (discharge side) of the circulation pump 4 is connected. Can be connected to the paint tank 2 side.

As shown in FIG. 1, when the primary side (suction side) of the circulation pump 4 is connected to the branch portion 3C side, the influence of the pulsating pressure of the circulation pump 4 on the print head 6 is in the negative pressure direction, and the paint injection The upper limit of the pressure applied to the tip of the gun 6 A is the pressure applied to the paint tank 2. In addition, since the paint filter 12 does not become a circulation resistance of the paint even if it is clogged, the paint pump 4 is not overloaded and the extruded paint does not become an abnormally high pressure. As a result, it is possible to suppress the occurrence of problems such as paint leakage from the tip of the paint spray gun 6A due to excessive pressure, damage to the paint spray gun 6A, and poor connection of tubes and joints in the paint circulation path 3. . In addition, since it is difficult for excessive pressure abnormality to occur, it is not necessary to provide a relief circuit or the like in the pressurization system.

The paint supply / printing apparatus 1 having such characteristics can avoid the deterioration of the printing performance due to the pulsation pressure of the circulation pump 4 without providing an accumulator (pulsation preventer) in the paint circulation path 3. Thereby, the paint supply printing apparatus 1 according to the embodiment of the present invention can have both the printing performance of the print head 6, the risk of equipment damage reduction, and the improvement of maintenance.

Particularly, in the paint supply printing apparatus 1 according to the embodiment of the present invention, the control unit 7 stops the circulation pump 4 when a signal is generated during printing. Therefore, the paint supply pressure applied to the print head 6 during printing is the regulator 2C. It becomes equal to the pressure in the paint tank 2 set to a constant value. As a result, the coating gun 6A can discharge the coating with a constant supply pressure, and high-quality printing with a uniform printing dot diameter can be obtained. In general, the printing time can be set to a time that hardly affects the separation or precipitation of the paint, so even if the circulation pump 4 is temporarily stopped, the quality of the paint is deteriorated or the maintainability of the paint circulation path 3 is deteriorated. The problem does not occur.

As described above, in the paint supply / printing apparatus 1 according to the embodiment of the present invention, since the pulsation pressure of the circulation pump 4 is irrelevant to the print quality, the paint circulation path 3 actively uses the pulsation pressure of the circulation pump 4. And clogging in the circulation pump 4 can be performed. Further, it is not necessary to increase the tube diameter of the paint circulation path 3 in order to suppress the pulsation of the supplied paint, and the tube system of the paint circulation path 3 can be made thin without requiring an accumulator. The paint flow rate can be increased and the amount of paint circulation can be minimized. As a result, problems such as separation / precipitation of the paint in the paint circulation path 3 and the circulation pump 4 can be fundamentally eliminated.

As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and the design can be changed without departing from the scope of the present invention. Is included in the present invention.

Claims

A sealable paint tank supplied with pressurized air;
A paint circulation path connected to the paint tank;
A circulation pump connected to the paint circulation path for circulating the paint in the paint tank along the paint circulation path;
A print head communicating with a paint supply path branched from the paint circulation path;
A control unit for controlling the printing operation of the print head and the operation of the circulation pump;
The said control part stops the said circulation pump at the time of printing operation of the said print head, The paint supply printing apparatus characterized by operating the said circulation pump at the time of printing stop of the said print head.
The paint supply printing apparatus according to claim 1, wherein a primary side of the circulation pump is connected to a branch side of the paint supply path, and a secondary side of the circulation pump is connected to the paint tank side.
The paint tank is made of a non-magnetic material, a non-contact stirrer is provided in the paint tank, and the paint tank is disposed on a magnetic drive unit that drives the non-contact stirrer to rotate in a non-contact manner. The paint supply printing apparatus according to claim 2.
An intermittent drive unit that intermittently drives the circulation pump and the magnetic drive unit, wherein the intermittent drive unit intermittently drives the circulation pump and the magnetic drive unit at set time intervals when the print head is not operating. The paint supply printing apparatus according to claim 3.
5. The paint supply printing apparatus according to claim 4, wherein an inlet end and an outlet end of the paint circulation path disposed in the paint tank are accommodated in one paint filter.