JP6116210B2 - Metal surface cleaning method - Google Patents

Description

The present invention relates to a metallic surface cleaning methods, particularly to Rukin genus surface cleaning method to clean the metal member oil is adhered to the surface.

  Conventionally, in metal products such as automobile bodies that have been processed by press molding or welding, after washing with water and degreasing, chemical conversion treatment (dipping in a processing solution stored in a processing tank) 2. Description of the Related Art A technique for performing a process for forming a chemical conversion coating such as a phosphoric acid coating on the surface of a product and then performing electrodeposition coating is widely known.

  Generally, since the surface of metal products is coated with oil such as rust preventive oil, when metal dust such as iron powder or weld spatter generated by processing comes into contact with the surface of metal products, many of them are metal products. It adheres directly to the surface. Such metal debris is almost removed in the process of washing and degreasing, but for example, some metal debris accumulated in the bag structure is not removed in the washing or degreasing process, but the chemical conversion treatment. Are often brought into the process.

  In such a case, the metal dust adhering to the metal product is dispersed and suspended in the treatment liquid for chemical conversion treatment (hereinafter referred to as “chemical conversion treatment liquid”). As a result, when the electrodeposition coating was performed, a coating defect was generated due to the occurrence of flaws.

  Then, the technique which attaches a plate-shaped magnet to the wall surface and bottom face of the process tank used in chemical conversion treatment is proposed (refer patent document 1). According to such a technique, the amount of metal dust floating in the chemical conversion treatment liquid can be reduced by the adsorption of metal dust by the magnet, and thus it is possible to suppress the above-described coating defects.

JP-A-60-216869

  However, in the technique described in Patent Document 1, metal dust floating in the chemical conversion treatment liquid is adsorbed by a magnet over a relatively long time, and therefore metal dust floating in the chemical conversion treatment liquid. Is likely to adhere to the metal product.

  That is, in the technique described in Patent Document 1, the inconvenience that a chemical conversion film is formed in a state in which metal dust is attached to the surface of a metal product cannot be wiped off, and the poor coating is sufficiently improved. It was hard to say.

This invention is made | formed in view of such a situation, The objective aims at the further suppression of the coating defect by removing effectively the dust adhering to the surface of the processed metal product. it is to provide a metallic surface cleaning method capable.

Before SL problem, according to the metal surface cleaning method of the present invention, after the processing step of generating a metal member by processing a metal material, the metal surface cleaning with a rinsing step of said metal member is washed with water An oil washing step of washing the metal member having oil adhered to the surface by a washing means with a washing oil after the processing step and before the water washing step, and the oil washing step A metal member heating step of heating the metal member by a metal member heating means before performing the water washing step, wherein the cleaning oil is at least of oil adhering to the metal member The cleaning means has a cleaning oil heating device that heats the cleaning oil, and the metal member heating means heats the cleaning oil by the cleaning oil heating device. Temperature higher than the In is resolved by the heating said metal member.

  In the said invention, the same kind of liquid (oil) as the liquid adhering to the surface of a metal member is used as a medium which wash | cleans the surface of a metal member.

  For this reason, when the cleaning oil comes into contact with the metal member, the surface of the metal member can be cleaned in a close contact state without being repelled like water.

  Here, oil (cleaning oil) has a relatively high viscosity among liquids. For this reason, when the cleaning oil contacts the metal member, the cleaning oil can be brought into close contact with the surface of the metal member for a long time.

  That is, according to the present invention, it is possible to capture dust such as dust and iron powder adhering to the surface over a relatively long time while maintaining adhesion to the surface of the metal member. .

  Moreover, when dust adhering to the surface of the metal member is captured, that is, when dust is taken into the cleaning oil, the movement of the dust in the cleaning oil is caused by the viscosity of the oil as described above. Therefore, it is possible to effectively suppress a situation where dust once captured in the cleaning oil adheres to the surface of the metal member again.

  Moreover, in the said invention, after wash | cleaning the metal member to which oil has adhered with the oil for washing | cleaning, the said metal member is also heated.

  According to such a configuration, since the cleaning oil adhering to the metal member is also heated by heating the metal member after cleaning with the cleaning oil, the viscosity of the cleaning oil decreases. Become. That is, since the cleaning oil adhering to the metal member is likely to be dropped due to a decrease in the adhesive force, it is possible to significantly improve the oil shortage of the cleaning oil.

  As described above, according to the present invention, the dust adhered to the metal member is effectively taken into the cleaning oil by cleaning the metal member with the cleaning oil, and the metal member is heated by the metal member heating means. Since the cleaning oil containing dust is efficiently removed from the metal member by heating, the occurrence of flaws in the coating film can be reduced as much as possible when the metal member is subjected to coating such as electrodeposition coating in the subsequent process. And a good coating film appearance can be provided.

  In addition, since the contamination of the processing liquid (for example, chemical conversion liquid or electrodeposition paint) used in the process after heating the metal member is reliably reduced, the life of the processing liquid is shortened. It is possible to suppress such a situation.

  As described above, according to the metal surface cleaning apparatus and the metal surface cleaning method according to the present invention, it is possible to effectively clean the metal member, and therefore it is possible to reliably reduce coating defects due to the occurrence of flaws. .

It is a flowchart which shows an example of the manufacturing process of the motor vehicle body which concerns on this embodiment. It is a schematic explanatory drawing which shows the outline of the manufacturing process of a motor vehicle body. It is a schematic explanatory drawing for demonstrating the metal surface cleaning apparatus used in an oil washing process. It is a front view for demonstrating arrangement | positioning of the nozzle of a 1st washing | cleaning apparatus. It is a top view for demonstrating arrangement | positioning of the side riser and bottom riser of a 2nd washing | cleaning apparatus.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart showing a manufacturing process of an automobile body according to the present embodiment, FIG. 2 is a schematic explanatory diagram for explaining an outline of the manufacturing process of an automobile body, and FIG. 3 is a metal surface cleaning apparatus used in an oil cleaning process. FIG. 4 is a front view for explaining the arrangement of the nozzles of the first cleaning device, and FIG. 5 is a plan view for explaining the arrangement of the side risers and the bottom risers of the second cleaning device. FIG.

  As shown in FIG. 1, the manufacturing process of the automobile body 1 according to the present embodiment includes a processing step A, an oil washing step B performed after the processing step A, and a first step performed after the oil washing step B. A water washing step C, a degreasing step D carried out after passing through the first water washing step C, a chemical conversion treatment step E carried out after going through the degreasing step D, a second water washing step F carried out after going through the chemical conversion treatment step E, And an electrodeposition coating process G performed after the second water washing process. The automobile body 1, the processing step A, the oil washing step B, the first water washing step C and the second water washing step F are respectively “metal member” and “oil” It corresponds to “washing process”, “processing process”, and “water washing process”.

  As shown in FIG. 2, the processing step A includes a process of punching a metal product (for example, an inner panel or an outer panel) constituting each member of the automobile body 1 from a metal plate such as a steel plate, and pressing the punched metal product. Processing, welding the pressed metal product, assembling the so-called white body (car body 1) by assembling the welded metal product, and the like. In addition, the said metal plate corresponds to the "metal material" as described in a claim.

Here, on the surface of the automobile body 1 on which the processing step A has been performed, oil (for example, rust preventive oil) previously applied to the metal plate, or oil (for example, applied when performing press processing or the like) , Press working oil) and the like are attached.
In addition, on the surface of the automobile body 1 to which such oil adheres, metal dust such as iron powder and welding spatter generated by performing the processing step A and other dust (hereinafter, metal dust and dust). Are collectively referred to as “garbage”).

  The automobile body 1 subjected to the processing step A is suspended by a hanger 2 and is moved by a ceiling conveyor 3 for moving the hanger 2. By such movement, the automobile body 1 is processed by the oil washing step B which is the next step. In the present embodiment, after the oil washing process B is performed, the first water washing process C, the degreasing process D, the chemical conversion treatment process E, the second water washing process F, the electricity are performed by the movement of the automobile body 1 by the ceiling conveyor 3. Processing in each process such as the coating process G is continuously performed.

Next, the oil washing step B will be described with reference to FIGS.
As shown in FIG. 2, in the oil washing step B, the first oil washing step B-1, the second oil washing step B-2 that is the next step of the first oil washing step B-1, and the second oil washing. And a metal member heating step B-3 which is the next step of the step. These 1st oil washing process B-1, 2nd oil washing process B-2, and metal member heating process B-3 are performed using the metal surface washing | cleaning apparatus 10. FIG. In addition, said 1st oil washing process B-1, 2nd oil washing process B-2, metal member heating process B-3, and the metal surface washing | cleaning apparatus 10 are respectively described in the claim. It corresponds to “spray cleaning process”, “immersion cleaning process”, “metal member heating process”, and “metal surface cleaning apparatus”.

  As shown in FIG.2 and FIG.3, when performing the 1st washing | cleaning apparatus 20 used when performing the 1st oil washing process B-1 and the 2nd oil washing process B-2, the metal surface washing | cleaning apparatus 10 performs. The 2nd washing | cleaning apparatus 30 used and the heating furnace 40 used when performing metal member heating process B-3 are provided. In addition, the said 1st washing | cleaning apparatus 20 and the 2nd washing | cleaning apparatus 30, and the heating furnace 40 correspond to the "cleaning means" and the "metal member heating means" as described in a claim, respectively.

First, the 1st washing | cleaning apparatus 20 used when performing 1st oil washing process B-1 is demonstrated with reference to FIG.3 and FIG.4.
As shown in FIG. 3, the first cleaning device 20 includes a plurality of nozzles 21 that can spray cleaning oil onto the automobile body 1, a drain pan 22, an oil tank 23, and a first circulation pump 24. The first heating device 25 and the first purification device 26 are provided. In addition, the said nozzle 21 and the 1st heating apparatus 25 correspond to the "spraying apparatus" and the "cleaning oil heating apparatus" as described in a claim, respectively.

As shown in FIG. 4, each of the plurality of nozzles 21 is attached to a pipe 55 connected to the first purification device 26, and the pipe 55 is moved by the ceiling conveyor 3 and is a moving space S of the automobile body 1. It is arranged at a position avoiding.
Each nozzle 21 is attached to the pipe 55 in such a direction that the cleaning oil can be sprayed onto the outer surface 1a of the automobile body 1 such as the roof portion and the hood portion.

  In the present embodiment, the same type of oil as the oil applied when the press process in the processing step A is performed (press processing oil) is used as the cleaning oil. In the present embodiment, the same type of oil as the press working oil is used as the cleaning oil used in the first cleaning device 20, but other types of oil may be used. At this time, it is preferable that the oil is the same type as at least one of the oils attached to the surface of the automobile body 1 (for example, the same type of oil as the rust preventive oil previously applied to the metal plate).

  As shown in FIGS. 3 and 4, the drain pan 22 is provided below the nozzle 21 and the moving space S (see FIG. 4), and the cleaning oil blown from the nozzle 21 and the cleaning oil dripped from the vehicle body 1. It is arranged at a position where it can be received.

  The drain pan 22 is bent from the upper end portion on the rear side in the movement direction of the automobile body 1 among the upper end portion of the oil dipping tank 31 described later, and extends toward the rear side in the movement direction. When the cleaning oil overflows from the drain pan 22, the overflowing cleaning oil flows into the oil dipping tank 31.

  A drain port 22 a is formed at a predetermined position on the bottom of the drain pan 22. A pipe 51 is connected to the discharge port 22 a, and the cleaning oil collected by the drain pan 22 is sent to the oil tank 23 through the pipe 51.

  The oil tank 23 has a size capable of storing a predetermined amount of cleaning oil, and is connected to the first circulation pump 24 via a pipe 52. The cleaning oil stored in the oil tank 23 is sucked by the activation of the first circulation pump 24 and is discharged to the first heating device 25 through the pipe 53.

  The 1st heating apparatus 25 is comprised by a well-known heat exchanger, an electric heater, etc., for example, and heat-controls cleaning oil so that it may become preset temperature.

  Such heating control can be realized, for example, by providing the temperature sensor 27 that detects the temperature of the cleaning oil in the pipe 54 and performing the heating control based on the temperature detected by the temperature sensor 27. In addition, it is not restricted to heating control based on the temperature of cleaning oil, For example, heating control of cleaning oil is performed based on the measured value of the viscometer (viscosity sensor) which detects the viscosity of cleaning oil. Is also possible.

  Here, the predetermined temperature is preferably set so as to be, for example, around 35 ° C. (within a range of 30 ° C. to 40 ° C.). In this way, a certain degree of viscosity is ensured in the cleaning oil, so that the cleaning oil blown from the nozzle 21 can be brought into close contact with the vehicle body 1, and as a result, the surface of the vehicle body 1 on the surface of the vehicle body 1. The attached dust can be captured (removed) for a relatively long time.

  The cleaning oil heated in this way is supplied to the first purification device 26 via the pipe 54 when the first circulation pump 24 is started.

  The first purification device 26 is constituted by, for example, a magnet filter capable of removing dust in the cleaning oil, and when the first circulation pump 24 is activated, the cleaning oil from which dust has been removed is This is supplied to the nozzle 21 via the pipe 55.

  In the first cleaning device 20 having such a configuration, when the first circulation pump 24 is started, the cleaning oil heated by the first heating device 25 and purified by the first purification device 26 is A plurality of nozzles 21 are blown out vigorously. Thereby, mainly, dust adhering to the outer surface 1a of the automobile body 1 is removed.

  The cleaning oil including the dust thus removed is collected by the drain pan 22 and supplied to the first heating device 25 through the pipe 51, the oil tank 23, the pipe 52, the first circulation pump 24 and the pipe 53. It has come to be. The cleaning oil is heated by the first heating device 25 so as to have a predetermined viscosity, and is supplied to the first purification device 26 via the pipe 54.

  The cleaning oil supplied to the first purification device 26 is configured to pass through the first purification device 26 to remove dust and to be blown out from the nozzle 21 again via the pipe 55. Yes.

Next, the 2nd washing | cleaning apparatus 30 used when performing 2nd oil washing process B-2 is demonstrated with reference to FIG.2, FIG3 and FIG.5.
As shown in FIG. 3, the second cleaning device 30 includes an oil dipping tank 31 that can store cleaning oil, a second purification device 32, a second heating device 33, and a second circulation pump 34. It has. The oil dipping tank 31 and the second heating device 33 correspond to the “treatment tank” and the “cleaning oil heating device” described in the claims, respectively.

  The oil dipping tank 31 stores the cleaning oil used in the first cleaning device 20, that is, the same type of oil as the oil applied when the pressing process in the processing step A is performed (press processing oil). Has been. In the present embodiment, as the cleaning oil used in the second cleaning device 30, the same type of oil as the press working oil is used, but other types of oil can also be used. At this time, it is preferable that the oil is the same type as at least one of the oils attached to the surface of the automobile body 1 (for example, the same type of oil as the rust preventive oil previously applied to the metal plate).

  In the second oil washing step B-2, a process of washing the automobile body 1 by immersing it in the washing oil stored in the oil dipping tank 31 is performed.

Here, the ceiling conveyor 3 in the section where the second oil washing step B-2 is performed will be described with reference to FIG.
As shown in FIG. 2, the ceiling conveyor 3 in the section in which the second oil washing step B-2 is performed is the movement direction of the automobile body 1 and the lower inclined portion 3a extending downward and inclined, and the movement of the lower inclined portion 3a. A horizontal portion 3b that is bent from the front end in the direction and extends horizontally along the moving direction, and an upper inclined portion 3c that is bent from the end on the front side in the moving direction of the horizontal portion 3b and that is inclined upward in the moving direction. have.

  When the automobile body 1 suspended by the hanger 2 passes through the lower inclined portion 3a and reaches the horizontal portion 3b, it is immersed in the cleaning oil stored in the oil dipping tank 31, and then the upper inclined portion 3c is It is configured to be pulled up from the cleaning oil as it moves.

Next, the oil dipping tank 31 will be described with reference to FIGS.
As shown in FIG. 3 and FIG. 5, the oil dipping tank 31 is directed toward both side surfaces (outer surface 1 a, see also FIG. 4) on both sides in the vehicle width direction of the automobile body 1 immersed in the cleaning oil. The cleaning oil is jetted toward a plurality of side risers (nozzles) 36 capable of jetting the cleaning oil and the inner surface 1c (see FIG. 4) of the automobile body 1 immersed in the cleaning oil. A plurality of bottom risers (nozzles) 37 are provided. The side riser 36 and the bottom riser 37 correspond to the “stirring device” recited in the claims.

  Of the side walls of the oil dipping tank 31, a pair of side walls 31a, 31a located in a direction intersecting with the moving direction of the automobile body 1 are respectively extended along the horizontal direction (moving direction of the automobile body 1). Pipes 61 and 61 are attached, and a side riser 36 is attached to each of the pipes 61 and 61 at a predetermined interval.

  The pipes 61 and 61 to which the side riser 36 is attached are connected to the pipe 62, respectively. This pipe 62 is branched out from a pipe 63 described later.

  Further, the bottom wall 31b of the oil dipping tank 31 is connected to the second purification device 32 and extends along the moving direction of the automobile body 1, and the movement of the automobile body 1 by this pipe 63. A pipe 64 that is connected to an end portion on the front side in the direction and extends along both sides of the moving direction of the automobile body 1 is attached. A plurality of bottom risers 37 are attached to the pipe 64 at predetermined intervals. Each of these bottom risers 37 is attached in such a direction that the cleaning oil is injected rearward in the moving direction of the automobile body 1 and upward.

  Of the side wall of the oil dipping tank 31, a discharge port 31d is formed at a predetermined position on the side wall 31c located on the rear side in the moving direction of the automobile body 1. A pipe 67 connected to the suction side of the second circulation pump 34 is attached to the discharge port 31d.

  Further, an overflow tank 38 capable of storing cleaning oil overflowing from the oil dipping tank 31 is provided at a position adjacent to the oil dipping tank 31. A pipe 68 to which an open / close valve 69 is attached is connected to the bottom of the overflow tank 38. In principle, the on-off valve 69 is closed, and is opened when the cleaning oil in the overflow tank 38 is discharged.

  A pipe 66 connected to the second heating device 33 is attached to the discharge side of the second circulation pump 34.

  Similarly to the first heating device 25, the second heating device 33 is configured by, for example, a known heat exchanger, an electric heater, or the like, and controls the heating of the cleaning oil so as to be within a preset temperature range. Is.

  Such heating control can be realized, for example, by providing the piping 65 with a temperature sensor 35 that detects the temperature of the cleaning oil, and performing the heating control based on the temperature detected by the temperature sensor 35. Note that the cleaning oil is not limited to the case of detecting the cleaning oil. For example, the cleaning oil is heated and controlled based on the measured value of a viscometer (viscosity sensor) that detects the viscosity of the cleaning oil flowing in the pipe 65. It is also possible.

  Here, it is preferable that the predetermined temperature is set to be higher than the first heating device 25, for example, around 60 ° C. (within a range of 55 ° C. to 65 ° C.). In this case, since the viscosity of the cleaning oil becomes low, the cleaning oil attached to the automobile body 1 when the automobile body 1 is taken out from the cleaning oil stored in the oil dipping tank 31. It becomes possible to quickly run out of oil.

  The cleaning oil heated in this way is supplied to the second purification device 32 via the pipe 65 when the second circulation pump 34 is activated.

  The second purification device 32 is configured by a magnet filter capable of removing dust such as iron powder in the cleaning oil, for example, similarly to the first purification device 26, and the cleaning oil from which dust has been removed is used. The side riser 36 and the bottom riser 37 are supplied via the pipes 61 to 64.

  In the second cleaning device 30 having such a configuration, when the second circulation pump 34 is activated, the cleaning oil heated by the second heating device 33 and purified by the second purification device 32 is It is ejected from the side riser 36 and the bottom riser 37. By such ejection of the cleaning oil from the side riser 36 and the bottom riser 37, the cleaning oil stored in the oil dipping tank 31 is well stirred.

  The automobile body 1 immersed in the cleaning oil stored in the oil dipping tank 31 is a portion (for example, a part) cleaned by the first oil cleaning step B-1 by the flow (stirring flow) of the cleaning oil to be stirred (for example, In addition to washing the outer surface 1a) of the automobile body 1, such as the roof portion and the hood portion, a slight portion not washed by the first oil washing step B-1, for example, the bag structure portion 1b (see FIG. 4) The inside is also cleaned.

  In this way, the dust removed from the automobile body 1 floats in the cleaning oil. However, the dust flows from the outlet 31d to the outside (pipe) of the oil dipping tank 31 along the stirring flow as described above. 67) is smoothly discharged.

  The dust discharged from the pipe 67 is supplied to the second heating device 33 via the second circulation pump 34 and the pipe 66. The cleaning oil is heated by the second heating device 33 so as to have a predetermined viscosity, and is supplied to the second purification device 32 via the pipe 65.

  The cleaning oil supplied to the second purification device 32 passes through the second purification device 32 to remove dust, and the side riser 36 and the bottom riser 37 again through the pipes 61 to 64. It is configured to be blown out from.

  In the present embodiment, as shown in FIG. 3, when the automobile body 1 is pulled up from the cleaning oil stored in the oil dipping tank 31 by the movement of the ceiling conveyor 3, it is blown out from the plurality of nozzles 39. It is comprised so that it may wash | clean with the oil for washing | cleaning. The nozzle 39 corresponds to “a spraying device” described in the claims.

  Similarly to the nozzle 21 of the first cleaning device 20, the nozzle 39 is provided at a position that is moved by the ceiling conveyor 3 and avoids the movement space of the automobile body 1. The direction is such that the cleaning oil can be sprayed onto the outer surface of the roof portion, the hood portion, and the like. Further, the cleaning oil sprayed on the automobile body 1 and the cleaning oil dropped from the automobile body 1 are collected by the oil dipping tank 31 and the overflow tank 38.

  The nozzle 39 is connected to a pipe 70 branched from the pipe 63, and is heated by the second heating device 33 and the second purification device 32 in the same manner as the side riser 36 and the bottom riser 37 of the second purification device 32. The cleaning oil purified by the above can be sprayed.

  In the present embodiment, most of the dust adhering to the automobile body 1 is removed by performing the first oil washing step B-1 and the second oil washing step B-2. After the oil washing step B-2, the spray cleaning by the nozzle 39 is further performed, so that the dust adhering to the automobile body 1 can be more reliably reduced. Further, the cleaning oil blown out from the nozzle 39 is a cleaning oil having a relatively low viscosity used in the second stage surface oil cleaning step B-2. It is possible to effectively drip.

Next, the heating furnace 40 used when performing metal member heating process B-3 is demonstrated with reference to FIG.
As shown in FIG. 2, the heating furnace 40 is configured such that the automobile body 1 can pass along with the movement of the ceiling conveyor 3, and the inside of the heating furnace 40 is heated by a heating device 41. It is configured.

  The heating device 41 includes, for example, a heat medium such as steam or a heater using electricity, and controls the heating so that the inside of the heating furnace 40 is maintained at a predetermined temperature.

  Here, the predetermined temperature is preferably set to a temperature (for example, 70 ° C. or higher) higher than that of the second heating device 33, for example. In this way, when the automobile body 1 enters the heating furnace 40, the cleaning oil adhering to the automobile body 1 is heated, so that the viscosity of the cleaning oil is changed in the second oil washing step. Since it becomes lower than the viscosity of the used cleaning oil, it is possible to efficiently drop the cleaning oil adhering to the automobile body 1 without dripping after the second oil washing step.

  After the oil washing process B as described above is performed, the first water washing process C, the degreasing process D, the chemical conversion treatment process E, the second water washing process F, and the electrodeposition coating are performed by moving the vehicle body 1 by the ceiling conveyor 3. Processing in each process such as process G is performed (see FIG. 1).

  Hereinafter, although the 1st water washing process C, the degreasing process D, the chemical conversion treatment process E, the 2nd water washing process F, and the electrodeposition coating process G are demonstrated, since these each process is well-known, the description is simplified and performed.

First, the 1st water washing process C is demonstrated.
As shown in FIG. 1, the first water washing step C includes a preliminary water washing step C-1 that is the next step of the oil washing step B and a main water washing step C-2 that is the next step of the preliminary water washing step C-1. I have.
As shown in FIG. 2, in the preliminary water washing step C- 1, hot water pressurized by a pressurizing device such as a pump is sprayed from a nozzle 71, mainly for a roof part or a hood part of the automobile body 1. The process which removes the dust adhering to the outer surface 1a (refer FIG. 4) is performed.
In the main water washing step C-2, the vehicle body 1 is immersed in warm water or the like stored in the treatment tank 72, and in addition to the portion washed by the preliminary water washing step C-1, the preliminary water washing step C-1 The part which was not wash | cleaned, for example, the process which wash | cleans the bag structure part 1b (refer FIG. 4), is performed.

As shown in FIGS. 1 and 2, the degreasing step D is a preliminary degreasing step D-1 that is the next step of the first water washing step C and a main degreasing step D-2 that is the next step of the preliminary degreasing step D-1. And.
As shown in FIG. 2, in the preliminary degreasing step D- 1, an alkaline degreasing liquid pressurized by a pressurizing device such as a pump is sprayed from a nozzle 73, and mainly a roof portion and a hood of the automobile body 1. A process of removing oil including cleaning oil adhering to the outer surface 1a (see FIG. 4) such as a part is performed.
In this degreasing step D-2, the vehicle body 1 is immersed in an alkaline degreasing solution stored in the treatment tank 74, and in addition to the outer surface of the vehicle body 1, such as the roof portion and the hood portion, the preliminary degreasing step D The part which was not defatted by -1, for example, the surface in the bag structure part 1b (refer FIG. 4), is degreased.

  As shown in FIG. 1, in the chemical conversion treatment step E, which is the next step of the degreasing step D, by immersing the automobile body 1 in a treatment liquid (chemical conversion treatment liquid), phosphate or the like is formed on the surface of the automobile body 1. The chemical conversion treatment film is formed.

  In the 2nd water washing process F which is the next process of the chemical conversion treatment process E, the process which wash | cleans the surface of the motor vehicle body 1 with warm water etc. is performed.

  In the electrodeposition coating process G that is the next process of the second water washing process F, the surface of the automobile body 1 is coated by immersing the automobile body 1 in the electrodeposition paint.

  Thus, according to the present embodiment, in the oil washing step B, as a medium for cleaning the surface of the automobile body 1, the same type of liquid (pressed oil) as the liquid adhering to the surface of the automobile body 1 (press processing oil) Oil).

  For this reason, when the cleaning oil comes into contact with the automobile body 1, for example, the surface of the automobile body 1 can be washed in a close contact state without being repelled like water.

  Moreover, since oil (cleaning oil) has a relatively high viscosity among liquids, when the oil comes into contact with the surface of the automobile body 1, the cleaning oil is applied to the surface of the automobile body 1 for a long time. It is possible to adhere.

  That is, according to the present embodiment, it is possible to capture the dust adhering to the surface of the automobile body 1 for a relatively long time while maintaining the adhesion to the surface of the automobile body 1.

  In addition, when dust adhering to the surface of the automobile body 1 is captured, that is, when dust is taken into the cleaning oil, the movement of the dust in the cleaning oil has the above-described oil. Since it is suppressed by the viscosity, it is possible to effectively suppress the situation where the dust once trapped in the cleaning oil adheres to the surface of the automobile body 1 again.

  Moreover, in this embodiment, after performing the 1st oil washing process B-1 which sprays and wash | cleans the said washing | cleaning oil on the surface of the motor vehicle body 1 to which oil is apply | coated, it is further stored by the oil dipping tank 31. In addition, the second oil washing step B-2 for immersing and washing the automobile body 1 in the washing oil is performed.

  That is, in the first oil washing step B-1, for example, dust stuck to the outer surface 1a such as a roof portion or a hood portion of the automobile body 1 can be removed by the cleaning oil sprayed on the automobile body 1. Is possible.

  Moreover, in 2nd oil washing process B-2, the 1st oil washing process other than wash | cleaning again the part (outer surface 1a) wash | cleaned by performing 1st oil washing process B-1 with washing | cleaning oil. It is possible to remove dust collected in the bag structure portion 1b, which has not been removed by the cleaning with B-1, with the cleaning oil.

  That is, according to the present embodiment, oil (cleaning oil) is used as a cleaning liquid for cleaning the automobile body 1, and cleaning (spray cleaning) and second oil cleaning step by the first oil cleaning step B-1. Since it is configured to perform different types of cleaning such as cleaning by B-2 (immersion cleaning), it is possible to effectively remove dust adhering to the automobile body 1.

  Furthermore, in this embodiment, after performing the 1st oil washing process B-1 and the 2nd oil washing process B-2, the metal member heating process B-3 which heats the motor vehicle body 1 with the heating furnace 40 is performed. It is configured.

  According to such a configuration, since the cleaning oil adhering to the automobile body 1 is also heated by the heating of the automobile body 1 by the heating furnace 40, the viscosity of the cleaning oil decreases. That is, since the cleaning oil adhering to the automobile body 1 is likely to be dropped due to a decrease in the adhesive force, it is possible to remarkably improve the oil shortage of the cleaning oil.

  Therefore, the cleaning oil containing dust captured by performing cleaning with the cleaning oil (cleaning by the first oil cleaning step B-1 and cleaning by the second oil cleaning step B-2) is performed from the automobile body 1. Since it removes efficiently, it can suppress reliably that the said garbage is brought into the subsequent process (1st water-washing process C-electrodeposition coating process G).

  For this reason, in the electrodeposition coating process G performed after performing the oil-washing process B (1st oil-washing process B-1, 2nd oil-washing process B-2, and metal member heating process B-3), in a coating film Generation | occurrence | production of a shading can be reduced as much as possible, and it becomes possible to provide a favorable coating-film external appearance.

  Moreover, since contamination of the processing liquid used in the chemical conversion treatment process E, the electrodeposition coating process G, etc. is reliably reduced, the life of the processing liquid is shortened due to the influence of the dust. Can be reliably suppressed.

  Furthermore, as described above, the amount of cleaning oil adhering to the automobile body 1 is reduced by performing the metal member heating step B-3, so that the amount of degreasing liquid used in the degreasing step D is reduced. Is possible.

  Furthermore, in this embodiment, the cleaning oil used in the first oil washing step B-1 and the cleaning oil used in the second oil washing step B-2 are respectively the first heating device 25 and the first oil washing step B-2. The viscosity is adjusted by being heated by the two heating device 33. That is, according to such a configuration, the viscosity of the cleaning oil used in the first oil washing step B-1 and the viscosity of the cleaning oil used in the second oil washing step B-2 with a simple configuration. Can be set to a desired value.

  In the present embodiment, the cleaning oil used in the first oil washing step B-1 and the cleaning oil used in the second oil washing step B-2 are oils attached to the surface of the automobile body 1 ( This is the same type of oil as press working oil). That is, when these cleaning oils come into contact with the surface of the vehicle body 1, they can be dissolved (neutralized) without difficulty in the oil adhering to the surface of the vehicle body 1. It is possible to capture (remove) more garbage.

  In the present embodiment, the automobile body 1 is shown as a metal member obtained by processing a metal material such as a metal plate. However, the present invention is applied to other metal members having oil attached to the surface. It is possible to apply.

  Moreover, in this embodiment, the washing | cleaning oil used in 1st oil washing process B-1 and the washing | cleaning oil used in 2nd oil washing process B-2 are the same kind (press processing oil). Although used, for example, the cleaning oil used in the first oil washing step B-1 is the rust-preventing oil (pressing oil), and the cleaning oil used in the second oil washing step B-2 is the pressing oil (anti-proofing). It is also possible to use different types of oil, such as rust oil.

  Furthermore, in this embodiment, although the 1st oil washing process B-1 and the 2nd oil washing process B-2 were performed, it is also possible to comprise so that only any one may be performed.

  In the present embodiment, the viscosity of the cleaning oil used in the first oil washing step B-1 and the viscosity of the cleaning oil used in the second oil washing step B-2 are made different from each other. However, they can be the same.

  Furthermore, in this embodiment, the cleaning oil used in the first oil washing step B-1 and the cleaning oil used in the second oil washing step B-2 are different from each other in the heating device (first heating device 25). Although it is configured to be heated by the second heating device 33), it may be configured to be heated by the same heating device.

  As mentioned above, although embodiment which applied the invention made | formed by this inventor was described, this invention is not limited by the description and drawing which make a part of indication of this invention by this embodiment. That is, it should be added that other embodiments, examples, operation techniques, and the like made by those skilled in the art based on this embodiment are all included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Automobile body 10 Metal surface cleaning apparatus 20 First cleaning apparatus 21 Nozzle 22 Drain pan 23 Oil tank 24 First circulation pump 25 First heating apparatus 26 First purification apparatus 30 Second cleaning apparatus 31 Oil dipping tank 32 Second purification apparatus 33 Second heating device 34 Second circulation pump 36 Side riser 37 Bottom riser 39 Nozzle 40 Heating furnace A Processing step B Oil washing step B-1 First oil washing step B-2 Second oil purification step B-3 Metal member heating Process C 1st water washing process F 2nd water washing process G Electrodeposition painting process

Claims (4)

A metal surface cleaning method comprising a water washing step of washing the metal member with water after performing a processing step of processing the metal material to generate the metal member,
After performing the processing step and before performing the water washing step, an oil washing step of washing the metal member having oil adhered to the surface by a washing means with washing oil;
A metal member heating step of heating the metal member by a metal member heating means after performing the oil washing step and before performing the water washing step,
The cleaning oil is the same type of oil as at least one of the oils adhering to the metal member,
The cleaning means has a cleaning oil heating device for heating the cleaning oil,
The metal member heating means heats the metal member at a temperature higher than the temperature at which the cleaning oil is heated by the cleaning oil heating device. The metal surface cleaning method according to claim 1 , wherein the oil washing step includes an immersion cleaning step of immersing and cleaning the metal member in the cleaning oil stored in a treatment tank. The method for cleaning a metal surface according to claim 2 , wherein the cleaning oil stored in the treatment tank is stirred by a stirring device. The metal surface cleaning method according to claim 1 , wherein the oil cleaning step includes a spray cleaning step of cleaning the metal member by spraying cleaning oil by a spraying device.

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