# US 4,400,416 A · Method of surface treatment and an apparatus used in said surface treatment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,400,416 A - Document ID: US4400416A - Status: Granted - Kind: A - Application number: 06/265,193 - Filed: 1981-05-19 - Granted: 1983-08-23 - Earliest claimed: 1981-05-19 - Assignees: Toyota Jidosha Kogyo Kabushiki Kaisha - Inventors: Yoshinobu Takahashi; Yasuo Tokushima; Kentarou Ogata; Mamoru Suzuki; Zyouzi Ito - Web page: https://patentgrep.com/patent/US4400416A ## CPC - C23C 22/00: Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals - B05C 3/10: the articles being moved through the liquid or other fluent material (conveying articles through baths B65G, e.g. B65G49/02) - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - B05C: APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (spraying apparatus, atomising apparatus, nozzles B05B; plant for applying liquids or other fluent materials to objects by electrostatic spraying B05B5/08) ## Abstract A method of surface treatment and an apparatus used in said surface treatment are provided in the present invention. Said method comprises dipping a surface-to-be-treated of an article in a treating liquid, moving said article in said treating liquid, letting the treating liquid flow in the reverse direction against said moving, spraying the treating liquid on the surface-to-be-treated of the article before and/or during said dipping and gush-spraying the treating liquid on the treated surface after said dipping; and said apparatus comprises a tank filled with a treating liquid, spraying tools arranged above and/or in said treating liquid in the front part of said tank, means of overflow formed in the front end of the tank, a container receiving the treating liquid overflowing from said means, a path recirculating the treating liquid from said container to the tank and a spraying tool arranged in the rear part of the tank. ## Claims ### Claim 1 An apparatus for surface treating articles, comprising: a dipping tank having a first end and a second end, said dipping tank being adapted to be filled with a treating liquid; means for moving articles to be treated through said tank in a first direction from said first end toward said second end; an overflow tank adjacent said first end; and first treating liquid spray means positioned over said tank and above the level of said treating liquid at said first end, second treating liquid spray means positioned below the level of said treating liquid at said first end, said first and second spray means each comprising at least one riser extending parallel to the surface of said liquid and to said first direction, and spray nozzles extending in said first direction on the upper surface of said risers so as to vertically spray said liquid, wherein said first and second risers and said means for moving are constructed and positioned so that said articles are sprayed only within a 30 second period before being dipped in said treating liquid and a 30 second period after being dipped in said treating liquid. ### Claim 2 (depends on 1) The apparatus of claim 1, further including: third treating liquid spray means adjacent the bottom of said tank; and fourth treating liquid spray means positioned above said liquid at said second end; and means for circulating said treating liquid from said overflow tank to said first, second, third and fourth spray means. ### Claim 3 (depends on 2) The apparatus in accordance with claim 2, wherein said means for moving comprise a conveyor moving a number of said articles and arranged over said tank. ### Claim 4 (depends on 2) The apparatus in accordance with claim 2, wherein said treating liquid is a zinc-phosphate solution. ### Claim 5 (depends on 4) The apparatus in accordance with claim 4, wherein said first spraying means is arranged so as to spray said liquid on the surface-to-be-treated within 30 sec. before the surface-to-be-treated is dipped into the liquid. ### Claim 6 (depends on 4) The apparatus in accordance with claim 4, wherein said second spraying means is arranged so as to spray said liquid on the treated surface within a fixed period after the treated surface is dipped in the liquid.