JPS6034767A - Drying device of automobile body after chemical conversion treatment - Google Patents

Abstract

PURPOSE:To provide a drying device after chemical conversion treatment of an automobile body capable of preventing unevenness of electrodeposition by elevating the temp. of car-body member by preheating by heating at least the last dipping tank for washing with water, and drying quickly by heating with gas at high-temp. CONSTITUTION:After subjecting a member of automobile cody to chemical conversion treatment, it is washed with water in a dipping tank. A heating means 21 is provided to at least the last dipping tank 20 and the car body member is preheated by elevating the temp. of the tank. Simultaneously, high-temp. gas is blown to the member in a direct heating furnace 10 to perform quick drying with hot gas. If the temp. of water in the dipping tank is not elevated sufficiently by some seasonal resaons, etc. and preheating of the member is insufficient, blowing out of hot gas at the inlet side of the direct heating furnace 10 is stopped and the temp. of the member is elevated to a desired temp. When the car-body member obtd. by the above described treatment is coated by electrodeposition, no uneveness of coating is resulted.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、塗装前処理としての化成処理を行った後の自
動車車体部品の乾燥装置に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a drying apparatus for automobile body parts after chemical conversion treatment as pre-painting treatment.

（従来技術） 自動車車体部品の塗装前処理として、湯洗、脱脂処理の
後、リン酸亜鉛などの化成被膜を表面に形成する化成処
理が一般に行われる。この被膜は、素地の腐食防止及び
塗料の密着性を向上させるものとして有効であるが、こ
の後の水洗、水切り乾燥工程における乾燥が不十分であ
ると、車体部品における合わせ部、溝部などに水が残り
電着塗膜の形成不良が生じたり、電着槽への入槽時に塗
装ムラ、すなわち、ノ＼ツシュマークが生じたりする。(Prior Art) As a pre-painting treatment for automobile body parts, a chemical conversion treatment is generally performed in which a chemical conversion film such as zinc phosphate is formed on the surface after hot water washing and degreasing treatment. This film is effective in preventing corrosion of the base material and improving the adhesion of paint, but if the subsequent washing and drying processes are insufficient, water may leak into joints, grooves, etc. of car body parts. This may result in poor formation of the electrodeposited film, or uneven coating, ie, scratch marks, may occur when the product is placed in the electrodeposition tank.

しかし、上記乾燥を十分に行っても下塗りのための電着
塗装において、局部的に厚い塗膜をもった塗装ムラカ；
発生し、その塗装ムラが上塗り塗装のムラとして現われ
ることがあった。従来では、この塗装ムラを未然に防止
する手段がなく、厚い塗膜を事後的に研磨処理によって
除去していた。However, even if the above-mentioned drying process is sufficiently performed, the electrodeposition coating for the undercoat still has a locally thick coating film.
Occasionally, the unevenness in the coating may appear as unevenness in the topcoat. Conventionally, there was no means to prevent this uneven coating, and the thick coating was removed by polishing after the fact.

本発明者らは、上記塗装ムラが化成処理後の乾燥方法に
起因していることを突き止め、本発明を完成するに至っ
たものである。The present inventors have discovered that the above-mentioned coating unevenness is caused by the drying method after chemical conversion treatment, and have completed the present invention.

（本発明の目的） 従って、本発明の目的は、電着塗装における上記塗装ム
ラの発生を未然に防止することができる化成処理後の乾
燥装置を提供することを目的とする。(Objective of the Present Invention) Therefore, an object of the present invention is to provide a drying device after chemical conversion treatment that can prevent the occurrence of the above-mentioned uneven coating in electrodeposition coating.

（本発明の構成及び効果） 本発明の上記目的は、以下の構成によりａ成することが
で酋る。すなわち、本発明は、表面に化成処理を施した
後、水洗し、乾燥し、その後電着塗装を行う自動車車体
部品の前記乾燥を行うための装置であって、前記水洗処
理を行うアイツブ槽のうち少くとも最終アイツブ槽に加
熱手段を備えるとともに、高温ガスの吹き出し手段な有
し前記車体部品に該高温ガスを吹き付けて直接熱風乾性
を行う直接加熱炉を備え、該直接加熱炉は少くとも入口
側の一部の高温ガスの吹き出しを停止できるようにしで
あることを特徴とする。(Configuration and Effects of the Present Invention) The above objects of the present invention can be achieved by the following configuration. That is, the present invention provides an apparatus for drying an automobile body part whose surface is subjected to a chemical conversion treatment, washed with water, dried, and then subjected to electrodeposition coating, the apparatus comprising: At least the final heating tank is equipped with a heating means, and a direct heating furnace is equipped with a means for blowing out high-temperature gas and directly performs hot air drying by blowing the high-temperature gas onto the vehicle body parts, and the direct heating furnace is equipped with at least an inlet. It is characterized by being able to stop blowing out some high temperature gas on the side.

水洗後の乾燥工程で生じる一般的な現象として、乾燥工
程の比較的初期の段階で局部的に水膜が切ね、部分的に
乾燥した状態になる。この部分乾燥状態はある期間維持
され、その後残りの部分に乾燥が進行し始めると完全乾
燥に致るまでの時間は比較的短い。A common phenomenon that occurs during the drying process after washing with water is that the water film breaks locally at a relatively early stage of the drying process, resulting in a partially dried state. This partially dry state is maintained for a certain period of time, and then when the remaining parts begin to dry, it takes a relatively short time to reach complete dryness.

この現象は、車体部品の表面温度が一定温度を越えたと
き、急速に乾燥が進行することに基づくと考えられる。This phenomenon is thought to be based on the fact that when the surface temperature of vehicle body parts exceeds a certain temperature, drying progresses rapidly.

本発明者らは、上記部分乾燥状態における乾一部と未載
１ハコ部すなわち渦れ部との境界付近の電Ｍ塗膜厚さが
他の部分より層、〈なり、これが塗装ムラの原因になっ
ていることを突き止めた。The present inventors discovered that in the partially dry state, the thickness of the electric M coating near the boundary between the dry part and the unmounted one box part, that is, the swirl part, is thicker than other parts, and this is the cause of coating unevenness. I found out that it was.

従って、塗装ムシの発生を未然に防止するためには、こ
の部分乾燥状態の発生を防ぐか、またＧま、その状態が
維持さＪｌろ時間を極力短くすれば良い。Therefore, in order to prevent the occurrence of paint blemishes, it is best to prevent the occurrence of this partially dry state, or to shorten the time period during which this state is maintained as much as possible.

本発明によれは、ディツノ゛槽のうち少くとも最終ディ
ップ槽に加熱手段を設けて、槽の水温を上げ車体部品を
予熱昇温するとともに、その後、直接加熱炉で高温ガス
を吹外付けて、急速に熱風乾燥するようにしている。こ
の場合、季節要因等によりアイツブ槽の水温を十分に高
めろことができず、従って車体部品をアイツブ槽で十分
予熱昇温することができないときには、直接加熱炉の入
口側の高温ガスの吹出しを停止して、車体部品な所望温
度まで昇温する。直接加熱炉の入口側のガスの吹出しを
停止した部分は、出口側の部分の高温ガスの吹出しによ
る熱を得てほぼ無風状態の高温室となり、この部分で車
体部品の表面からの蒸発を抑制しつつ昇温することがで
きる。すなわち、車体部品の表面を儒れた状態に維持し
つつディップ槽での予熱不足を補って所望温朋まで昇温
することができる。According to the present invention, at least the final dipping tank of the dipping tank is provided with a heating means to raise the water temperature in the tank to preheat and heat up the car body parts, and after that, high-temperature gas is directly blown outside in a heating furnace. , to quickly dry with hot air. In this case, if it is not possible to sufficiently raise the water temperature in the Aitubu tank due to seasonal factors, and therefore the car body parts cannot be sufficiently preheated in the Aitubu tank, the high temperature gas may be blown directly from the inlet of the heating furnace. Stop and heat the vehicle body parts to the desired temperature. The part on the inlet side of the direct heating furnace where gas blowing is stopped receives heat from the hot gas blowing out from the outlet side, creating a high-temperature chamber with almost no wind, and this part suppresses evaporation from the surface of car body parts. It is possible to raise the temperature while That is, it is possible to compensate for insufficient preheating in the dip tank and raise the temperature to a desired temperature while maintaining the surface of the vehicle body part in a pliable state.

従って、上記塗装ムラの発生原因である部分乾燥状態の
継続な極力短縮することができる。Therefore, it is possible to reduce the duration of the partial drying state, which is the cause of the above-mentioned uneven coating, as much as possible.

ディップ槽の水温を加熱する手段としてはスチームを循
環はせる加熱コイルをテ゛・ｆツブ槽内に配設すること
が芋けられ、水温の制御はスチーム温度及び？Ｉｎ　量
に調整することによって行うことができる。この場合、
車体部品の表面温度は約３０Ｃ以上に昇温することが望
ましく、このためＫはアイツブ槽の水温は７００以上が
適当である。As a means of heating the water temperature in the dip tank, it is recommended to install a heating coil that circulates steam in the dip tank, and the water temperature can be controlled by the steam temperature and the water temperature. This can be done by adjusting the In amount. in this case,
It is desirable that the surface temperature of the vehicle body parts be raised to about 30C or higher, and for this reason, it is appropriate that the water temperature of the water tank is 700C or higher.

直接熱風乾燥を行う直接加熱炉は、炉内雰囲気温度／　
１０Ｃ−／！；ＯＣ，車体部品滞溜時間Ｓ〜ノθ分、対
流流速６〜／　Ｏｍ　／　ｓｅｅで運転されることが望
ましい。A direct heating furnace that performs direct hot air drying has a temperature of
10C-/! It is desirable to operate at OC, vehicle body parts retention time S~ no θ minutes, and convection flow rate 6~/Om/see.

直接加熱炉の入口側のガス吹出を停止して高温室として
予熱不足を補填する８我性は、王として夏以外の時期に
生じ、この場合、以下の系外を充足すれば好ましい結果
を得ることかでべろ。雰囲気温度！；０−１０θＣ１車
体部品ｆ：１１溜時間／分（春秋）、ｌ５分（冬）。Stopping the gas blowout on the inlet side of the direct heating furnace and making up for the lack of preheating by creating a high-temperature chamber 8. This phenomenon occurs during seasons other than summer, and in this case, favorable results can be obtained by fulfilling the following external conditions. Let's talk about it. Atmosphere temperature! ;0-10θC1 car body parts f: 11 storage time/minute (spring/autumn), 15 minutes (winter).

（実施例の説明） （比較例） 自動車車体部品の＠装前処理を第１図に示すよりに行っ
た。まず車体部品の湯洗脱脂処理す行い、つづいて水洗
した後、表面にリン酸亜鉛等の化成膜を形成する化成処
理ｆＸ：施した。(Description of Examples) (Comparative Example) Automotive body parts were pre-treated as shown in FIG. First, the car body parts were washed with hot water and degreased, then washed with water, and then subjected to chemical conversion treatment fX: which forms a chemical film of zinc phosphate or the like on the surface.

化成処理後、ディップ槽すなわち水タンクに車体部品を
浸漬して水洗するデイツブ操作を以下の糸外で行った。After the chemical conversion treatment, a dipping operation in which the car body parts were immersed in a dip tank, that is, a water tank and washed with water, was performed as follows.

（最終ディップ操作） 水温　３Ｃ−コθＣ 全没時間　２分間 タンク容量　７０ｍ３ 次に、車体部品を下記の糸件でスプレー洗浄を行った。(Final dip operation) Water temperature 3C-koθC Total immersion time: 2 minutes Tank capacity 70m3 Next, the car body parts were spray cleaned using the following thread.

水温　３Ｃ−２０Ｃ スプレー時間　１０〜２０秒間 スプレー旦　２０θｔ／ｍｌｎ 次に第２図及び第３図に示す直接乾燥炉で車体部品な乾
燥した。第２図及び第３図を参照すれば、直接乾燥炉１
０の車体部品１２の搬送方向の両側壁面に沿って複数の
噴出口１４を偏見たヘッダー１６．１Ｂが取付けられて
いる。これらのヘッダー１６．１８バーナー２２からの
高温ガスが送風ファン２４によって送られ、ダクト２Ｂ
、２８を介して供給されるようになっている。ダクト２
６．２Ｂにはガス量を調整して炉内温度を制御するため
の調整弁３２．３４がそれぞれ設けられている。Water temperature: 3C-20C Spray time: 10 to 20 seconds Spray time: 20θt/mln Next, the car body parts were dried in a direct drying oven shown in FIGS. 2 and 3. Referring to FIGS. 2 and 3, the direct drying oven 1
A header 16.1B having a plurality of ejection ports 14 biased thereon is attached along both side wall surfaces in the transport direction of the vehicle body part 12 of No. 0. The hot gas from these headers 16.18 burners 22 is sent by a blower fan 24 to the duct 2B.
, 28. Duct 2
6.2B are provided with regulating valves 32 and 34, respectively, for adjusting the gas amount and controlling the furnace temperature.

車体部品１２は第３図において左方から炉内に入り、右
方に移動しながら、高温ガスを吹付けられて乾燥される
。The vehicle body part 12 enters the furnace from the left in FIG. 3 and is dried by being blown with hot gas while moving to the right.

調整弁３２．３４の一部を全開にすると、その部分の雰
囲気はほぼ無風の高温変化する。従って、車体部品から
の蒸発を極力抑制しつつ表面温度を上昇させることがで
へる。直接乾燥炉の運転条件は以下の通りである。When a part of the regulating valves 32, 34 is fully opened, the atmosphere in that part changes to a high temperature with almost no wind. Therefore, it is possible to raise the surface temperature while suppressing evaporation from the vehicle body parts as much as possible. The operating conditions of the direct drying oven are as follows.

雰囲気温度　１ｉｏｃ〜１ｓｏｃ 時間　５−ｉｏ分 風速　４〜７０ｍ／度 雰囲気中の特定成分 ＣＯ・・・・・・Ｓ〜／　Ｏｐｐｍ Ｎｏｘ　−−・−３〜４Ｌ　ｐｐｍ　（Ｍａｘ　１５ｐ
ｐｍ）α　・・・・・・数ｐｐｍ 以上の処理によって得られた車体部品は電着塗装後にお
いて、電着塗膜表面にスジ状の段差が生じるという不具
合が発生した。このスジ状の段差は高さ７μ〜スμ、長
さ２ｒａｎ以上にわたるものであった。この例の条件は
特に冬期に普通に遭遇するもので、場所は王としてぎン
ネット、ルーフ、トランクの部品に発生し易い。発生率
は、ボンネットを例にとれは、約６θ係のボンネットに
上記現象が見られた。Atmosphere temperature: 1 ioc ~ 1 soc Time: 5 io min Wind speed: 4 ~ 70 m/degree Specific component in atmosphere CO...S~/Oppm Nox ---3~4L ppm (Max 15p
pm) α ......Several ppm or more The car body parts obtained by the treatment had a problem in that after the electrodeposition coating, streak-like steps were formed on the surface of the electrodeposition coating. This striped step had a height of 7 μm to 3 μm and a length of 2 ran or more. This example condition is commonly encountered, especially during the winter months, and is most likely to occur in areas such as nets, roofs, and trunk parts. As for the occurrence rate, taking bonnets as an example, the above phenomenon was observed in bonnets with an angle of approximately 6θ.

（実施例） 第を図に示すように化成処理までの操作は、上述の比較
例と同様の条件で行った。本例では第Ｓ図に示すように
最終ディップ槽２０にスチームが循環する加熱コイル２
１を配設し水温を比較的高く維持した。最終ディップ槽
の運転条件は以下のとおりである。(Example) As shown in the figure, operations up to chemical conversion treatment were performed under the same conditions as in the above-mentioned comparative example. In this example, as shown in FIG.
1 was installed to maintain the water temperature relatively high. The operating conditions of the final dip tank are as follows.

水温　弘ＯＣ以上 全没時間　ユ分間 タンク容量　７０ｍ３ 次に以下の条件で車体部品のスプレー洗浄をスプレー時
間３０で行った。Water temperature: Hiro OC or higher Total immersion time: 70 m3 Tank capacity: 70 m3 Next, the car body parts were spray-cleaned with a spray time of 30 m3 under the following conditions.

水温　ｔｉ−ｓｃ スプレー時間　／゛θ〜２００ 〜２０秒間　コθＯｔ／ｍｌｎ 次に、第２図及び第３図に示す乾燥炉１０において、調
整弁３２．３４０入口側の一部を全開として、車体部品
の予熱昇温を行った。加熱条件は、以下の通りである。Water temperature ti-sc Spray time /゛θ~200~20 seconds θOt/mln Next, in the drying oven 10 shown in Figs. 2 and 3, a part of the inlet side of the regulating valve 32, 340 is fully opened, and Parts were preheated and heated. The heating conditions are as follows.

雰囲気温度　ｇＯＣ 車体部品滞溜時間　１５分 対流流速　７ｍ／ｍ／下 次に、乾燥炉１０の出口側部分の噴出口１４から高温ガ
スを吹付けて熱風乾燥を行った。この場合の処理条件は
以下のとおりである。Atmosphere temperature: gOC Residence time of vehicle body parts: 15 minutes Convection flow rate: 7 m/m/lower Next, hot air drying was performed by blowing high-temperature gas from the outlet 14 at the outlet side of the drying oven 10. The processing conditions in this case are as follows.

雰囲気温度　／３θＣ 車体部品滞溜時間　３分 対流流速　ｇｍ１％ 以上の処理によって得られた車体部品の電着塗装後の表
面における不具合は冬期においても見られなかった。こ
れは、ディップ槽に加熱コイル２１を挿入して水温を高
くすることにより、車体部品の表面温度を上昇させるこ
とができろとともに、季節要因等によってディップ槽で
の昇温か十分でｌｌ／′１＠合には、力日熱炉の入口側
の部分を非蒸発性雰囲気にして澗れた状態で所望の温度
まで上昇させるようにしているためである。すなわち、
ディップ槽の水温状態の変動に拘わらず塗装ムラの発生
な防止することができる。Atmospheric temperature: /3θC Residence time for vehicle body parts: 3 minutes Convection flow rate: gm1% No defects were observed on the surfaces of vehicle body components obtained after electrodeposition coating, even in winter. This is because by inserting the heating coil 21 into the dip tank and raising the water temperature, the surface temperature of the car body parts can be raised, and depending on seasonal factors, the heating temperature in the dip tank may be sufficient to 1/'1. In this case, the temperature is raised to the desired temperature in a stagnant state by creating a non-evaporative atmosphere at the inlet side of the thermal furnace. That is,
It is possible to prevent uneven coating from occurring regardless of fluctuations in the water temperature state of the dip tank.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は、従来の塗装前処理の概略流れ図、第２図は、
乾燥炉の横断面を示した概略図、第３図は、乾燥炉の平
断面を示した概略図、第弘図は、本発明に従う処理の概
略流れ図、第Ｓ図は、本発明に従う処理装置の概略図で
ある。 符号の説明 １０・・・・・・乾燥炉　１２・・・・・・車体部品２
０・・・・・・加熱コイル　２２・・・・・・ノ々−ナ
ー２４・・・・・・送風ファン 特許出願人　東洋工業株式会社 第１図 第２図Figure 1 is a schematic flowchart of conventional painting pretreatment, and Figure 2 is:
FIG. 3 is a schematic diagram showing a cross section of the drying oven; FIG. 3 is a schematic diagram showing a plan cross section of the drying oven; FIG. FIG. Explanation of symbols 10...Drying oven 12...Car body parts 2
0...Heating coil 22...Nononer 24...Blower fan Patent applicant Toyo Kogyo Co., Ltd. Figure 1 Figure 2

Claims (1)

【特許請求の範囲】[Claims] 表面に化成処理を施した後、水洗し、乾燥し、その後電
着塗装を行う自動車車体部品の前記乾燥を行うための装
置であって、前記水洗処理を行うディップ宿のうち少く
とも最終ディップ宿に加熱手段を備えるとともに、高温
ガスの吹き出し手段を有し前記車体部品に該高温ガスを
吹き付けて直接熱風乾燥を行う直接乾燥炉を備え、該直
接乾燥炉は少くとも入口側の一部の高温ガスの吹き出し
を停止でべろようにしであることを特徴とする自動車車
体部品の化成処理後の乾燥装置。A device for drying an automobile body part whose surface is subjected to a chemical conversion treatment, washed with water, dried, and then subjected to electrodeposition coating, wherein at least the final dip shelter is used for the washing treatment. is equipped with a heating means and a direct drying oven which has a means for blowing out high temperature gas and directly performs hot air drying by blowing the high temperature gas onto the vehicle body parts; A drying device for car body parts after chemical conversion treatment, characterized in that the blowing of gas is stopped and the drying device is dry.