Method and device for stripping coating on surface of metal plate

Abstract

The invention provides a stripping method and device for a film on the surface of a metal plate, and the stripping method comprises the steps that a suction and blowing head is moved to the surface of the film-coated metal plate through a moving device, and the suction and blowing head comprises a suction cup, a hot air pipeline and an air blowing pipeline; the sucking unit is used for sucking air from the blowing and sucking head, so that a sucking disc of the blowing and sucking head forms negative pressure and is in close contact with the film-coated metal plate; hot air is blown into the suction cup through the hot air pipeline, the covering film below the suction cup is softened and expanded, the suction rate is further increased through the suction unit, and the surface of the covering film is raised; and the suction-blowing head moves in the direction away from the film-coated metal plate through the moving device, and air blowing is stopped but the negative pressure of the suction unit on the suction cup is kept until the film is completely stripped. Through the technical means of negative pressure adsorption and hot air softening, the purpose of efficiently and losslessly removing the film on the surface of the metal plate is achieved, and the metal plate surface stripping device has the advantages of being high in stripping efficiency, not scratching the metal surface and the like and is suitable for the metal plate machining pretreatment link in an automatic production line.

Description

Technical Field

[0001] The invention relates to the technical field of film stripping, and in particular to a method and a device for stripping a film on a surface of a metal plate. Background Art

[0002] Laminated metal sheet is a material that is coated on the surface of a metal sheet through a hot melt coating process. It has excellent mechanical strength, excellent barrier properties, excellent formability, recyclability and aesthetics, and is a high-quality packaging material. During the processing, the surface coating attached to the metal sheet needs to be removed to facilitate processing. For example, when cutting with laser blanking, the coating of the metal sheet must be removed, otherwise the high temperature of the laser beam will make it difficult to clean the coating adhered to the blanking after cutting. At the same time, the plastic melting during the cutting process will produce smoke that affects the environment. Therefore, before processing the metal sheet, the surface coating of the metal sheet to be processed must be removed.

[0003] In the prior art, mechanical clamping methods are mostly used to remove the surface coating of metal plates, such as using clamping jaws to clamp the coating from the edge of the sheet. Various flat-angle clamps are not easy to clamp the coating, but the sharp clamps are easy to scratch the metal surface when clamping, and the coating is easy to fall off the clamps. Summary of the invention

[0004] In view of this, the present invention proposes a method and device for stripping the film on the surface of a metal plate to solve the technical problems that the various flat-angle clamps proposed in the above background technology are not easy to clamp the film, but the sharp clamps are easy to scratch the metal surface when clamping, and the film is easy to fall off the clamps.

[0005] The technical solution of the present invention is achieved in this way:

[0006] In a first aspect, the present invention provides a method for stripping a coating on a surface of a metal plate, comprising:

[0007] The suction and blowing head is moved to the surface of the coated metal plate by a moving device, wherein the suction and blowing head comprises a suction cup, a hot air pipeline and a blowing pipeline;

[0008] The suction unit is used to evacuate the blowing and suction heads, so that the suction cups of the blowing and suction heads form negative pressure and are in close contact with the coated metal plate;

[0009] Hot air is blown into the suction cup through the hot air pipeline to soften and expand the film under the suction cup, and the suction unit further increases the air extraction volume to make the surface of the film bulge;

[0010] The suction and blowing head is moved away from the coated metal plate by a moving device until the coating is completely peeled off, and then the blowing is stopped but the negative pressure of the suction unit on the suction cup is maintained.

[0011] On the basis of the above technical solution, preferably, after further increasing the air extraction volume to make the coating surface bulge, the method further comprises:

[0012] The membrane is penetrated by a thorn tube, so that the raised membrane is in close contact with the inner wall of the suction cup, and the thorn tube is connected with the air blowing pipeline;

[0013] Close the hot air pipeline and blow air into the thorn tube through the air blowing pipeline to expand the gas volume between the film and the metal plate, pulling the film and the metal plate to peel off.

[0014] On the basis of the above technical solution, preferably, the air flow rate of the air blown into the piercing tube by the air blowing pipeline is adjusted according to the minimum width of the metal plate, the height of the suction and blowing head and the stripping time, and the air flow rate Q1 of the air blown into the piercing tube is Q2=(A 2 ×H / 3) / t;

[0015] Wherein, Q1 is the air flow rate of the blown air, L / s; A is the minimum width of the metal plate, mm; H is the height of the suction and blowing head, mm; t is the peeling time, s.

[0016] On the basis of the above technical solution, preferably, the temperature of the hot air is controlled within the range of 60-90°C.

[0017] On the basis of the above technical solution, preferably, after the coating is completely peeled off, it also includes: using a moving device to enable the suction and blowing head to drive the coating to move to above the waste box, and stopping the negative pressure on the suction cup, and after the coating falls from the suction cup into the waste box, the suction and blowing head is withdrawn from the processing area by the moving device.

[0018] In a second aspect, the present invention provides a device for stripping a metal plate surface coating, comprising a suction and blowing head, a moving device, a suction unit, a heating unit and a blowing unit, wherein:

[0019] The suction and blowing head includes a suction cup, and a suction pipeline, a hot air pipeline and a blowing pipeline connected to the suction cup. The bottom of the suction cup is conical so that the surface of the adsorbed film is raised.

[0020] The moving device is connected to the suction cup and is used to drive the suction cup to move;

[0021] The suction unit is connected to the suction pipeline and is used to form a negative pressure on the suction cup so that the suction cup is in close contact with the coated metal plate;

[0022] The heating unit is connected to the hot air pipeline and is used to blow hot air into the suction cup to soften and expand the film under the suction cup;

[0023] The blowing unit is connected to the blowing pipeline and is used for quickly blowing air after closing the hot air pipeline to pull the film and the metal plate to be peeled off.

[0024] On the basis of the above technical solution, preferably, the suction and blowing head also includes a barbed tube, which is respectively connected to the air blowing pipeline and the hot air pipeline and is located in the suction cup, and the barbed tube is used to penetrate the film during the process of film swelling, so that the raised film is in close contact with the inner wall of the suction cup.

[0025] On the basis of the above technical solution, preferably, it also includes a control unit, which is electrically connected to the blowing unit and is used to adjust the air flow rate of the blowing pipeline according to the minimum width of the metal plate, the height of the suction and blowing head and the peeling time.

[0026] On the basis of the above technical solution, preferably, the suction and blowing head also includes an air suction control valve, a hot air control valve and an air blowing control valve, the air suction control valve is arranged on the air suction pipeline, the hot air control valve is arranged on the hot air pipeline, and the air blowing control valve is arranged on the air blowing pipeline.

[0027] The method for stripping the metal plate surface coating of the present invention has the following beneficial effects compared with the prior art:

[0028] (1) The suction unit is used to evacuate the suction head so that the suction cup of the suction head forms a negative pressure and is in close contact with the coated metal plate. The hot air pipeline blows hot air into the suction cup to soften and expand the film under the suction cup. The suction unit further increases the suction volume to make the surface of the film bulge. The moving device moves the suction head away from the coated metal plate so that the film is completely peeled off. The purpose of efficiently and non-destructively removing the film on the surface of the metal plate is achieved through the technical means of negative pressure adsorption and hot air softening. It has the advantages of high peeling efficiency and no scratching of the metal surface, and is suitable for the pretreatment link of metal plate processing in the automated production line.

[0029] (2) After the surface of the film is raised, the film can be penetrated by a piercing tube so that the raised film is in close contact with the inner wall of the suction cup. The piercing tube is connected to the air blowing pipeline. The hot air pipeline is closed, and air is blown into the piercing tube through the air blowing pipeline to expand the gas volume between the film and the metal plate, pull the film and the metal plate to peel off, and improve the peeling efficiency;

[0030] (3) The air flow rate of the air blown into the piercing tube through the air blowing pipeline is adjusted according to the minimum width of the metal plate, the height of the suction and blowing head and the stripping time. By inputting the corresponding parameters, the air flow rate of the air blown into the piercing tube through the air blowing pipeline can be controlled, and the corresponding flow rate can be adjusted to save energy. The whole process has a high degree of automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a schematic flow chart of a method for stripping a coating on a metal plate surface in an embodiment of the present invention;

[0033] Figure 2 This is a state diagram of the film under the suction cup in an embodiment of the present invention being separated from the local metal plate and the suction and blowing head starting to lift;

[0034] Figure 3 This is a state diagram of the film being completely peeled off in the late stage of suction and blowing in an embodiment of the present invention;

[0035] Figure 4 It is a schematic structural diagram of a suction and blowing head of a device for stripping a metal plate surface coating in an embodiment of the present invention.

[0036] Description of reference numerals: 1-suction and blowing head;

[0037] 100-metal plate, 200-film;

[0038] 11-suction cup, 12-suction pipeline, 13-hot air pipeline, 14-blowing pipeline, 15-thorn tube, F6-suction control valve, F7-hot air control valve, F8-blowing control valve. DETAILED DESCRIPTION

[0039] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Reference Figure 1-3 As shown, the first embodiment of the present invention provides a method for stripping a coating on the surface of a metal plate, comprising:

[0041] Step S1: moving a suction and blowing head to the surface of the coated metal plate by a moving device; the suction and blowing head includes a suction cup, a hot air pipeline and a blowing pipeline;

[0042] Step S2: exhausting the blowing and suctioning head through the suction unit so that the suction cup of the blowing and suctioning head forms a negative pressure and is in close contact with the coated metal plate; the bottom of the suction cup is conical to form a conical space;

[0043] Step S3: Blow hot air into the suction cup through the hot air pipeline to soften and expand the film 200 under the suction cup, and further increase the suction volume through the suction unit to make the surface of the film 200 bulge;

[0044] Step S4: The coating 200 is penetrated by a piercing tube, so that the raised coating is in close contact with the inner wall of the suction cup, and the piercing tube is connected to the blowing pipeline;

[0045] Step S5: closing the hot air pipeline and blowing air into the thorn tube through the air blowing pipeline to expand the gas volume between the film 200 and the metal plate 100, pulling the film 200 and the metal plate 100 to peel off;

[0046] Step S6: The suction and blowing head is moved away from the coated metal plate by the moving device until the coating 200 is completely peeled off, and then the blowing is stopped but the negative pressure of the suction unit on the suction cup is maintained;

[0047] Step S7: The suction and blowing head drives the coating 200 to move to the top of the waste box through the moving device, and stops the negative pressure on the suction cup. After the coating 200 falls from the suction cup into the waste box, the suction and blowing head is withdrawn from the processing area through the moving device.

[0048] It should be noted that the specific parameters in this embodiment are as follows: the material of the coating 200 on the surface of the 1.2mm stainless steel metal plate 100 is polyvinyl chloride (PVC), which is pressed onto the surface of the stainless steel metal plate 100 at a high temperature of 110 degrees using a special vacuum laminating machine. The film thickness is 0.25-0.30mm and is not easy to fall off.

[0049] The method for stripping the film on the surface of a metal plate proposed in the present embodiment uses a suction unit to evacuate the suction head so that a negative pressure is formed on the suction cup of the suction head and the suction cup is in close contact with the coated metal plate; a hot air pipeline blows hot air into the suction cup to soften and expand the film 200 under the suction cup; the suction volume is further increased by the suction unit to cause the surface of the film 200 to bulge; a moving device moves the suction head away from the coated metal plate so that the film 200 is completely stripped off; the technical means of negative pressure adsorption, hot air softening and cold air stripping are used to achieve the purpose of efficiently and non-destructively removing the film 200 on the surface of the metal plate 100; the method has the advantages of high stripping efficiency and no scratching of the metal surface, and is suitable for the pretreatment link of metal plate 100 processing in an automated production line.

[0050] In some embodiments, the air flow rate of the air blown into the piercing tube by the air blowing pipeline is adjusted according to the minimum width of the metal plate 100, the height of the suction and blowing head and the stripping time. The air flow rate Q1 of the air blown into the piercing tube is (A 2 ×H / 3) / t;

[0051] Wherein, Q1 is the air flow rate of the blown air, L / s; A is the minimum width of the metal plate 100, mm; H is the lifting height of the suction and blowing head, mm; t is the peeling time, s.

[0052] In some embodiments, the temperature of the hot air is controlled within the range of 60-90°C. PVC begins to soften at about 80-85°C, at which time its physical properties change, such as reduced hardness and increased toughness. As the temperature continues to rise, PVC will further soften and transform into a viscoelastic state and a viscous flow state, so the temperature of the hot air is controlled below the over-softening range. The temperature of the hot air is preferably 60-90°C.

[0053] In some embodiments, before the puncture tube pierces the membrane 200 , the flow rate of the hot air is Q2 = Q3 ; after the puncture tube pierces the membrane 200 , Q2 = 0.

[0054] Q3=[(π×R 2 ×H1) / 3] / t1;

[0055] Where, Q3 is the flow rate to fill the suction cup cone, L / s; π is the circumference; R is the radius of the cone base, mm; H1 is the height of the cone, mm; t1 is the time of filling with hot air, s; θ is the inner cone angle of the suction cup, which ranges from 30-60°. In this application case, R = 75mm, θ = 30°.

[0056] Based on the same concept, the second embodiment of the present invention provides a device for stripping the film on the surface of a metal plate, comprising a suction and blowing head 1, a moving device, a suction unit, a heating unit and a blowing unit, wherein:

[0057] like Figure 4 As shown, the suction and blowing head 1 includes a suction cup 11, and a suction pipeline 12, a hot air pipeline 13 and a blowing pipeline 14 connected to the suction cup 11. The bottom of the suction cup 11 is conical so that the surface of the adsorbed coating 200 is raised;

[0058] The moving device is connected to the suction cup 11 and is used to drive the suction cup 11 to move; the moving device may be a movable mechanical structure or a robot;

[0059] The suction unit is connected to the suction pipeline 12 and is used to form a negative pressure on the suction cup 11 so that the suction cup 11 is in close contact with the coated metal plate;

[0060] The heating unit is connected to the hot air pipeline 13 and is used to blow hot air into the suction cup 11 to soften and expand the coating 200 under the suction cup 11;

[0061] The blowing unit is connected to the blowing pipeline 14 and is used to quickly blow air after closing the hot air pipeline 13 to pull the film and the metal plate 100 to peel off.

[0062] In some embodiments, the suction and blowing head 1 further includes a thorn tube 15, which is connected to the air blowing pipeline 14 and the hot air pipeline 13 respectively and is located in the suction cup 11. The thorn tube 15 is used to penetrate the film during the swelling of the film 200, so that the swelling film is in close contact with the inner wall of the suction cup 11. The film 200 is penetrated by the thorn tube 15, so that the swelling film is in close contact with the inner wall of the suction cup 11, and then the hot air pipeline 13 is closed, and air is blown into the thorn tube 15 through the air blowing pipeline 14 to expand the gas volume between the film 200 and the metal plate 100, pull the film 200 and the metal plate 100 to be peeled off, and improve the peeling efficiency.

[0063] In some embodiments, the device for stripping the metal plate surface coating also includes a control unit, which is electrically connected to the blowing unit and is used to adjust the air flow rate of the blowing pipeline 14 according to the minimum width of the metal plate 100, the height of the suction and blowing head 1 and the stripping time.

[0064] In some embodiments, the suction and blowing head 1 further includes a suction control valve F6, a hot gas control valve F7 and a blowing control valve F8, wherein the suction control valve F6 is arranged on the suction pipeline 12, the hot gas control valve F7 is arranged on the hot gas pipeline 13, and the blowing control valve F8 is arranged on the blowing pipeline 14. The suction control valve F6, the hot gas control valve F7 and the blowing control valve F8 control the opening and closing of the suction pipeline 12, the hot gas pipeline 13 and the blowing pipeline 14 to achieve gas control.

[0065] The working process of the stripping device for the metal plate surface coating is as follows:

[0066] Use a moving device to move the suction and blowing head 1 to the surface of the coated metal plate, open the suction control valve F6, and under the suction effect of the suction pipeline 12, negative pressure (P6=65-35KPa) appears under the suction cup 11, and the edge of the suction cup 11 is in close contact with the coated metal plate.

[0067] Hot air (85-90°C) is blown in through the hot air pipeline 13 to soften and expand the film 200 under the suction cup 11, and the suction volume of the suction unit is further increased to make the surface film of the film 200 bulge. Figure 2 As shown;

[0068] In the process of continuous small-amplitude bulging, the film is penetrated by the thorn tube 15 in the suction and blowing head 1, and the bulged film is in close contact with the inner wall of the suction cup 11, so as to achieve adsorption and traction of the bulged end; before and after the thorn tube 15 pierces the film, the film is softened and expanded by controlling the change of the hot air flow Q2;

[0069] Close the hot air control valve F7 and open the blowing control valve F8. Air quickly enters from the blowing pipe 14 of the suction and blowing head 1, rapidly expanding the gas volume between the metal plate 100 and the film 200, pulling the film and the metal plate 100 to peel off until the minimum width direction (A) of the metal plate 100 is peeled off, and the blowing flow rate Q1 reaches the maximum value, and the time t = 3.5 seconds;

[0070] At the same time, the suction and blowing head 1 is moved upward to a height H (see Figure 3 ), accelerate the peeling process, until the peeling is complete, stop blowing, close the blowing control valve F8, but the suction control valve F6 is still open to maintain the negative pressure at the suction end;

[0071] The moving device moves to remove the peeled coating 200 to the waste box, and the moving device takes the suction and blowing head 1 out of the sheet material processing area to carry out the next mechanical or laser processing.

[0072] The device for stripping the surface coating of a metal plate proposed in the present invention achieves the purpose of efficiently and non-destructively removing the surface coating 200 of the metal plate 100 by combining the technical means of negative pressure adsorption, hot air softening and cold air stripping. Compared with the prior art, the present invention has the advantages of high stripping efficiency and no scratching of the metal surface, and is suitable for the pretreatment link of metal plate 100 processing in an automated production line.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for stripping a film on a metal plate surface, characterized in that: include: The suction and blowing head is moved to the surface of the coated metal plate by a moving device, wherein the suction and blowing head comprises a suction cup, a hot air pipeline and a blowing pipeline; The suction unit is used to evacuate the blowing and suction heads, so that the suction cups of the blowing and suction heads form negative pressure and are in close contact with the coated metal plate; Hot air is blown into the suction cup through the hot air pipeline to soften and expand the film under the suction cup, and the suction unit further increases the air extraction volume to make the surface of the film bulge; The suction and blowing head is moved away from the coated metal plate by a moving device until the coating is completely peeled off, and then the blowing is stopped but the negative pressure of the suction unit on the suction cup is maintained.

2. The method for stripping a film on a metal plate surface according to claim 1, wherein: After further increasing the air extraction volume to make the coating surface bulge, the method further includes: The membrane is penetrated by a thorn tube, so that the raised membrane is in close contact with the inner wall of the suction cup, and the thorn tube is connected with the air blowing pipeline; Close the hot air pipeline and blow air into the thorn tube through the air blowing pipeline to expand the gas volume between the film and the metal plate, pulling the film and the metal plate to peel off.

3. The method for stripping a film on a metal plate surface according to claim 2, wherein: The air flow rate of the air blown into the piercing tube by the air blowing pipeline is adjusted according to the minimum width of the metal plate, the height of the suction and blowing head and the stripping time. The air flow rate Q1 of the air blown into the piercing tube is (A 2 ×H / 3) / t; Wherein, Q1 is the air flow rate of the blown air, L / s; A is the minimum width of the metal plate, mm; H is the height of the suction and blowing head, mm; t is the peeling time, s.

4. The method for stripping a film on a metal plate surface according to claim 1, wherein: The temperature of the hot air is controlled within the range of 60-90°C.

5. The method for stripping a film on a metal plate surface according to claim 1, wherein: After the coating is completely peeled off, the method further includes: using a moving device to enable the suction and blowing head to drive the coating to move to above a waste box, and stopping the negative pressure on the suction cup, and after the coating falls from the suction cup into the waste box, the suction and blowing head is withdrawn from the processing area by the moving device.

6. A device for stripping a film on a metal plate surface, characterized in that: It includes a suction and blowing head, a moving device, a suction unit, a heating unit and a blowing unit, wherein: The suction and blowing head includes a suction cup, and a suction pipeline, a hot air pipeline and a blowing pipeline connected to the suction cup. The bottom of the suction cup is conical so that the surface of the adsorbed film is raised. The moving device is connected to the suction cup and is used to drive the suction cup to move; The suction unit is connected to the suction pipeline and is used to form a negative pressure on the suction cup so that the suction cup is in close contact with the coated metal plate; The heating unit is connected to the hot air pipeline and is used to blow hot air into the suction cup to soften and expand the film under the suction cup; The blowing unit is connected to the blowing pipeline and is used for quickly blowing air after closing the hot air pipeline to pull the film and the metal plate to be peeled off.

7. The device for removing the film from the surface of a metal plate according to claim 6, characterized in that: The suction and blowing head also includes a thorn tube, which is respectively connected to the blowing pipeline and the hot air pipeline and is located in the suction cup. The thorn tube is used to penetrate the film during the film swelling process so that the swelling film is in close contact with the inner wall of the suction cup.

8. The device for removing the film from the surface of a metal plate according to claim 7, characterized in that: It also includes a control unit, which is connected to the blowing unit by electrical signals and is used to adjust the air flow rate of the blowing pipeline according to the minimum width of the metal plate, the height of the suction and blowing head and the stripping time.

9. The device for removing the film from the surface of a metal plate according to claim 8, characterized in that: The suction and blowing head also includes an air suction control valve, a hot air control valve and an air blowing control valve. The air suction control valve is arranged on the air suction pipeline, the hot air control valve is arranged on the hot air pipeline, and the air blowing control valve is arranged on the air blowing pipeline.

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