Method for manufacturing lap joint of organic layer coated metal sheets, and apparatus for manufacturing lap joint of organic layer coated metal sheets

Abstract

To provide a method for manufacturing an organic matter layer coated metal plate lap joint, and an apparatus for manufacturing an organic matter layer coated metal plate lap joint which can suppress deterioration in an organic matter layer than conventional manufacturing method and manufacturing apparatus, when an organic matter layer coated metal plate is friction-welded.SOLUTION: A method for manufacturing an organic matter layer coated metal plate lap joint includes the steps of: fixing a plate set to an anvil; press-fitting a connection member to the plate set; and friction-welding a metal plate contacting the anvil and the tip of a shaft part, wherein a cylindrical sleeve is press-fit to the plate set from an opposite side to the anvil, and thereby the plate set is fixed to the anvil, the connection member is pressed to the plate set through the inside of the sleeve, an organic matter layer is arranged on one or both of the plate set, the organic matter layer is cooled using the sleeve when the organic matter layer contacts the sleeve, and the organic matter layer is cooled using the anvil when the organic matter layer contacts the anvil.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a lap joint of metal sheets coated with an organic layer, and an apparatus for manufacturing a lap joint of metal sheets coated with an organic layer. [Background technology]

[0002] Metal plate lap joints, obtained by joining a set of overlapping metal plates, are included in the joints of various machine parts. The most commonly used method for joining metal plates is welding. Examples of welding methods used for joining plate sets include spot welding, arc welding, and laser welding.

[0003] However, during welding, the joint is heated to a temperature above the melting point of the metal plates. This can cause deterioration of the mechanical properties of the metal plates at the joint and its surroundings. This phenomenon is particularly noticeable in steel plates, especially high-strength steel plates with a tensile strength of 780 MPa or more.

[0004] Welding is also not suitable for joining dissimilar materials. When dissimilar materials are melted and mixed and then solidified, a large amount of brittle intermetallic compounds is formed in the weld metal. Therefore, it is difficult to ensure sufficient joint strength when welding dissimilar materials.

[0005] Friction welding has been gaining attention in recent years as another method for joining metal plates. Friction welding is a pressure welding method in which two parts are brought into contact with each other and pressure is applied by utilizing the frictional heat (raising the temperature near the joint) generated by rotating one or both parts or another friction element (JIS Z 3001-2:2018).

[0006] Friction welding is sometimes called friction welding. However, the welded area does not usually melt or solidify during friction welding. In friction welding, the surface of the base material is removed, and the newly exposed surface is heated by friction heat to a temperature below the melting point, activated, and then pressed to form the welded area. Therefore, the friction welded area usually does not contain weld metal.

[0007] Friction welding has traditionally been used to join rod-shaped materials such as pipes in the longitudinal direction. For example, Patent Document 1 discloses a friction welding method for propeller shafts in which a thin-walled pipe and a thick-walled pipe are arranged coaxially and their end faces are abutted and rotated relative to each other to generate frictional heat to press-weld both end faces together, characterized in that the inner diameter of the thin-walled pipe is smaller than the inner diameter of the thick-walled pipe.

[0008] However, in recent years, attempts have been made to lap-join multiple metal plates using friction welding, using a rivet-like connecting member having a head and a shank. In this friction welding method, a connecting member having a shank and a head is pressed into a sheet assembly until the tip of the shank contacts the metal plate arranged on the outermost surface of the sheet assembly. Then, the tip of the shank is friction-welded to the metal plate arranged on the outermost surface of the sheet assembly. As a result, the metal plate friction-welded to the tip of the shank and the head provided at the base end of the shank sandwich the metal plate penetrated by the shank, mechanically joining the sheet assembly. Lap-joining of metal plates by friction welding can be said to be a joining method that combines friction welding and mechanical joining.

[0009] When joining metal plates using friction welding, the metal plates do not melt or mix together. Therefore, friction welding can easily join metal plates made of different materials. In addition, the heat input during friction welding is smaller than that during welding. Therefore, friction welding is less likely to cause thermal degradation of the joint and its surroundings.

[0010] Patent Document 2, for example, discloses a technique for joining metal plates using friction welding. The technique involves joining at least two flat plates, one of which is a support plate with greater strength than the other supported plate placed on top of it, via a joining element rotated by a rotary feeder unit. The joining element presses the supported plate against the support plate with a collar and forms a friction welded joint with the support plate via a shaft. The rotary feeder unit is equipped with a measuring device that measures the axial force and each feed distance applied by the rotary feeder unit, sends a signal indicating an increase in pressing force caused by lowering the shaft unit of the joining element, and advances the rotary feeder unit. The apparatus completes the friction welding process by adjusting the feed operation of the rotary feeder unit through at least three consecutive joining stages: a first stage for adjusting the feed so that the rotary feeder penetrates the supported plate; a second stage for adjusting the friction welding between the shaft unit and the support plate; and a third stage for applying the axial force of the joining element to the support plate. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-141933 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-062748 Summary of the Invention [Problem to be solved by the invention]

[0012] In recent years, metal sheet lap joints have been required to have even higher corrosion resistance. To improve corrosion resistance, it is preferable to coat the surface of a metal sheet lap joint with an organic layer such as a paint film. However, welding is not suitable for joining metal sheets whose surfaces are coated with an organic layer, i.e., organic layer-coated metal sheets. When organic layer-coated metal sheets are welded, welding defects occur due to the inclusion of the organic layer or gas generated from the organic layer in the weld metal. Therefore, it is difficult to ensure joint strength when welding organic layer-coated metal sheets. Furthermore, if the organic layer is an insulator, resistance welding such as spot welding is difficult.

[0013] Therefore, the present inventors attempted to join metal plates coated with an organic layer by friction welding, and as a result, it was confirmed that the organic layer did not interfere with friction welding and that good joint strength could be ensured.

[0014] On the other hand, when organic layer-coated metal plates are joined by friction welding, it has been found that the organic layer deteriorates and peels off around the connecting member, as shown in Figure 4. The corrosion resistance of the metal plate lap joint is impaired at the peeled-off portion of the organic layer. This peeling of the organic layer is likely to occur when multiple joints are performed consecutively. There have been no reports of organic layer deterioration or peeling when organic layer-coated metal plates are joined consecutively multiple times by friction welding. Therefore, the organic layer deterioration phenomenon discovered by the inventors is unknown to those skilled in the art. Incidentally, there have been reports of friction welding metal plates having metal plating such as Zn plating instead of an organic layer, but in these cases, plating deterioration is not a concern.

[0015] In view of the above circumstances, the present invention aims to provide a method for manufacturing an organic substance layer-coated metal sheet lap joint, and an apparatus for manufacturing an organic substance layer-coated metal sheet lap joint, which can suppress deterioration of the organic substance layer more than conventional methods when friction-welding organic substance layer-coated metal sheets. [Means for solving the problem]

[0016] The gist of the present invention is as follows.

[0017] (1) A method for manufacturing an organic layer coated metal sheet lap joint according to a first embodiment of the present invention includes the steps of: fixing a sheet assembly consisting of a plurality of overlapping metal sheets to an anvil; press-fitting a connecting member having a shank and a head provided at the base end of the shank into the sheet assembly from the opposite side of the anvil until the metal sheet in contact with the anvil comes into contact with the tip of the shank; friction-welding the metal sheet in contact with the anvil and the tip of the shank, and using the head to weld the metal sheet through which the shank has penetrated to the metal sheet through which the shank has been friction-welded. and a step of mechanically joining the plate to the anvil, wherein in the fixing step, the plate set is fixed to the anvil by pressing a cylindrical sleeve against the plate set from the opposite side of the anvil, and in the pressing step, the connecting member is pressed into the plate set through the inside of the sleeve, an organic material layer is disposed on one or both surfaces of the plate set, and when the organic material layer and the sleeve come into contact, the organic material layer is cooled using the sleeve, and when the organic material layer and the anvil come into contact, the organic material layer is cooled using the anvil. (2) In the manufacturing method of the organic material layer-coated metal sheet lap joint described in (1) above, when the organic material layer and the sleeve are in contact with each other, the organic material layer may be cooled by making the sleeve out of copper or a copper alloy and / or by providing the sleeve with a cooling mechanism using a refrigerant, and when the organic material layer and the anvil are in contact with each other, the organic material layer may be cooled by making the anvil out of copper or a copper alloy and / or by providing the anvil with a cooling mechanism using a refrigerant. (3) In the manufacturing method of the organic material layer-coated metal sheet lap joint described in (1) above, when the organic material layer and the sleeve are in contact with each other, the organic material layer may be cooled by providing a cooling mechanism using a refrigerant on the sleeve, and when the organic material layer and the anvil are in contact with each other, the organic material layer may be cooled by providing a cooling mechanism using a refrigerant on the anvil. (4) In the method for producing a lap joint of organic layer-coated metal sheets according to any one of (1) to (3) above, the organic layer may be in contact with the sleeve. (5) In the method for manufacturing a lap joint of organic layer coated metal sheets described in (4) above, a chamfer having a radius of 0.1 mm or more may be provided on the inner edge of the end face of the sleeve that contacts the organic layer. (6) A manufacturing method of an organic substance layer-coated metal sheet lap joint according to a second embodiment of the present invention includes the steps of: fixing a sheet assembly consisting of a plurality of overlapping metal sheets to an anvil; pressing a connecting member having a shaft and a head provided at the base end of the shaft into the sheet assembly from the opposite side of the anvil until the metal sheet in contact with the anvil comes into contact with the tip of the shaft; friction-welding the metal sheet in contact with the anvil to the tip of the shaft, and mechanically joining the metal sheet through which the shaft has penetrated to the metal sheet to which the shaft has been friction-welded, using the head; and an organic substance layer is disposed on at least the surface of the sheet assembly in contact with the anvil, and cooling the organic substance layer using the anvil. (7) In the manufacturing method of the organic layer-coated metal sheet lap joint described in (6) above, the organic layer may be cooled by making the anvil out of copper or a copper alloy and / or by providing the anvil with a cooling mechanism using a refrigerant. (8) In the method for producing a lap joint of organic layer-coated metal sheets described in (6) above, the organic layer may be cooled by providing the anvil with a cooling mechanism that uses a refrigerant. (9) In the method for producing a lap joint of organic layer-coated metal sheets according to any one of (1) to (8) above, at least one of the plurality of metal sheets may be a steel sheet.

[0018] (10) A manufacturing apparatus for an organic layer-coated metal plate lap joint according to a third embodiment of the present invention includes an anvil configured to fix a plate assembly consisting of a plurality of overlapping metal plates, a rotary pressing mechanism that presses a connecting member having a shaft portion and a head portion provided at a base end of the shaft portion against the plate assembly from the opposite side of the anvil while rotating the connecting member around the axis of the connecting member, and a cylindrical sleeve that is pressed against the plate assembly from the opposite side of the anvil to fix the plate assembly, wherein the rotation axis of the rotary pressing mechanism is inside the sleeve, The sleeve However, there is no cooling means. death , The sleeve cools the organic layer. . (11) In the manufacturing apparatus for an organic layer coated metal sheet lap joint described in (10) above, the cooling means is made of copper or a copper alloy. The sleeve itself, and The sleeve The cooling mechanism may be one or both of the cooling mechanisms using a refrigerant provided in the cooling device. (12) In the manufacturing apparatus for an organic layer coated metal sheet lap joint described in (10) above, the cooling means is The sleeve The cooling mechanism may be a refrigerant cooling mechanism provided in the 。 ( 1 3 ) above (1 0 In the manufacturing apparatus for a lap joint of organic layer-coated metal sheets described in the above, the sleeve may have a chamfered portion with a radius of 0.1 mm or more on the inner edge of the end surface that contacts the organic layer. 。 [Effects of the Invention]

[0019] According to the present invention, it is possible to provide a method for manufacturing an organic substance layer-coated metal sheet lap joint, and an apparatus for manufacturing an organic substance layer-coated metal sheet lap joint, which can suppress deterioration of the organic substance layer more than conventional methods when friction-welding organic substance layer-coated metal sheets. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a schematic diagram of a method for manufacturing an organic layer-coated metal sheet lap joint according to a first embodiment. FIG. [Figure 2] FIG. 10 is a cross-sectional schematic view of a cooling mechanism for the anvil and sleeve. [Figure 3] 5 is a schematic diagram of a method for manufacturing an organic layer-coated metal sheet lap joint according to a second embodiment. FIG. [Figure 4] 1 is a schematic diagram of a method for manufacturing an organic layer-coated metal sheet lap joint using a conventional metal sheet lap joint manufacturing apparatus. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0021] The method for producing an organic layer-coated metal sheet lap joint according to the first embodiment of the present invention includes the steps of: (S1) a step of fixing a plate set B composed of a plurality of overlapping metal plates B1 and B2 to an anvil 11; (S2) a step of press-fitting a connecting member C having a shaft portion C2 and a head portion C1 provided at a base end of the shaft portion C2 into the plate assembly B from the opposite side of the anvil 11 until the first metal plate B1 in contact with the anvil 11 comes into contact with the tip of the shaft portion C2; (S3) frictionally welding the first metal plate B1 in contact with the anvil 11 to the tip of the shank C2, and mechanically joining the second metal plate B2 through which the shank C2 has penetrated by the head C1 to the first metal plate B1 to which the shank C2 has been frictionally welded; Here, in the fixing step S1, a cylindrical sleeve 12 is pressed against the plate set B from the opposite side of the anvil 11, thereby fixing the plate set B to the anvil 11, and in the press-fitting step S2, a connection member C is pressed against the plate set B through the inside 122 of the sleeve 12. An organic layer E is disposed on one or both surfaces of the plate set B, and when the organic layer E and the sleeve 12 contact each other, the organic layer E is cooled using the sleeve 12, and when the organic layer E and the anvil 11 contact each other, the organic layer E is cooled using the anvil 11.

[0022] The organic layer-coated metal plate lap joint A obtained by the above-mentioned method comprises a plate assembly B consisting of a first metal plate B1 arranged as the outermost layer and one or more second metal plates B2 overlapped on the first metal plate B1, and a connecting member C having a shaft portion C2 that is friction-welded perpendicularly to the first metal plate B1 and passes through the second metal plate B2, and a head portion C1 that is provided at the base end of the shaft portion C2 and mechanically joins the first metal plate B1 and the second metal plate B2, and one or both surfaces of the plate assembly B are coated with an organic layer E.

[0023] The method for manufacturing a lap joint of organic layer-coated metal sheets according to the first embodiment will be described in detail below.

[0024] (Fixed process S1) First, a plate set B consisting of a plurality of overlapping metal plates is fixed to an anvil 11. Here, an organic layer E is disposed on one or both surfaces of the plate set B. This makes it possible to manufacture an organic layer-coated metal plate lap joint A whose surfaces are coated with the organic layer E. The number of metal plates included in the plate set B may be two, three or more.

[0025] Hereinafter, for convenience, the metal plate arranged on the outermost layer of the plate set B and in contact with the anvil 11 will be referred to as the first metal plate B1, and the other metal plates will be referred to as the second metal plates B2. The first metal plate B1 is the metal plate to which the tip of the shank C2 of the connecting member C is friction-welded, and the second metal plate B2 is the metal plate through which the shank C2 of the connecting member C passes. The number of first metal plates B1 is one. The number of second metal plates B2 may be one or two or more.

[0026] In the manufacturing method according to the first embodiment, the plate set B is fixed to the anvil 11 by a cylindrical sleeve 12. Specifically, the cylindrical sleeve 12 is vertically abutted against the surface of the plate set B on the opposite side of the anvil 11. Then, the sleeve 12 is pressed against the plate set B from the opposite side of the anvil 11. Note that a fixing jig other than the sleeve 12 may be used in combination to more firmly fix the plate set B and the anvil 11.

[0027] (Press-fitting process S2) The head C1 provided at the base end of the shaft C2 is connected to the rotary pressing mechanism 13 of the manufacturing apparatus 1 for the organic layer-coated metal sheet lap joint A. The head C1 provided at the base end of the shaft C2 may be connected to the rotary pressing mechanism 13 in advance of the fixing step S1. The connecting member C is pressed perpendicularly against the plate set B from the opposite side of the anvil 11, and the tip of the shaft C2 is brought into contact with the plate set B.

[0028] Next, the connecting member C is rotated and pressed, thereby pressing the shaft portion C2 of the connecting member C into the plate assembly B and penetrating the metal plates. Since the plate assembly B is fixed to the anvil 11, the connecting member C rotates relative to the plate assembly B in the press-fitting step S2 and subsequent steps. The connecting member C is also pressed against the plate assembly B through the inner side 122 of the sleeve 12. This allows the sleeve 12 to fix the periphery of the connecting member C with a uniform pressure force, stabilizing the joining operation. As described above, in this embodiment, the metal plate to be penetrated is referred to as the second metal plate B2.

[0029] The press-fitting step S2 continues until the tip of the shank C2 of the connection member C comes into contact with the metal plate in contact with the anvil 11, i.e., the first metal plate B1. The length of the shank C2 of the connection member C is made sufficiently longer than the total thickness of the second metal plate B2, allowing the tip of the shank C2 to come into contact with the first metal plate B1. Furthermore, to facilitate penetration, it is preferable that the tip of the shank C2 of the connection member C is sharpened rather than flat. However, the press-fitting step S2 is a step of penetrating the second metal plate B2 with the tip of the shank C2 of the connection member C and bringing it into contact with the first metal plate B1, and any method can be used. As described above, the connection member C may be pressed while being rotated to penetrate the second metal plate B2, or a through-hole may be formed in the second metal plate B2 in advance, and the connection member C may be pressed without being rotated to penetrate the second metal plate B2.

[0030] (Friction welding process S3) By further rotating and pressing the connecting member C, the contact area between the tip of the shank C2 and the first metal plate B1 is heated. Furthermore, at the contact area, the tip of the shank C2 and the outermost surface of the first metal plate B1 are removed, revealing a new surface. When the rotation of the connecting member C is stopped, the new surface is immediately cooled by heat transfer from the new surface to the surrounding area. After cooling, the two activated new surfaces are firmly joined, forming a friction welded joint D.

[0031] When the tip of the shank C2 of the connecting member C is frictionally welded to the first metal plate B1, the second metal plate B2 is disposed between the first metal plate B1 joined to the tip of the connecting member C and the head C1 provided at the base end of the connecting member C. In other words, the head C1 of the connecting member C mechanically joins the second metal plate B2, through which the shank C2 of the connecting member C passes, to the first metal plate B1 to which the shank C2 of the connecting member C is frictionally welded.

[0032] Through the above steps, an organic layer-coated metal sheet lap joint A is obtained in which one or both surfaces are coated with an organic layer E. However, the present inventors have discovered that the organic layer E disposed on the surface may peel off, as shown in Figure 4. The present inventors have examined the peeled area in detail and have confirmed the following facts. (1) As shown in FIG. 4, when the sleeve 12 and the organic layer E were in contact with each other, the organic layer E peeled off at the location where the sleeve 12 was pressed. (2) As shown in FIG. 4, when the anvil 11 and the organic layer E were in contact with each other, the organic layer E peeled off at the location where the connecting member C was pressed. (3) When friction welding was performed multiple times in a short period of time using one joining device, the incidence of peeling increased as the number of times increased.

[0033] Previously, the harmful effects of frictional heat during friction welding were not recognized. In resistance welding, such as spot welding, the weld is cooled via the electrode to prevent electrode deterioration due to welding heat and promote solidification of the molten metal. However, in friction welding, the connection member C is replaced with a new one each time the welding is performed. Therefore, thermal degradation of the connection member C and its surrounding components was not considered a problem. Rather, excessive cooling of the connection member C is considered undesirable, as it facilitates plastic deformation of the connection member and promotes the creation of a newly activated surface. In the prior art, cooling of the friction-welded area meant cooling after the rotational pressure of the connection member was stopped. Furthermore, the adverse effects of frictional heat on surface treatment were not known. In fact, when friction welding was performed using the above procedure on galvanized steel sheets, which have a relatively low melting point, no peeling of the galvanized coating occurred.

[0034] However, the inventors have hypothesized that the frictional heat generated during the pressing step S2 to the friction welding step S3 moves to and accumulates in the sleeve 12 and the anvil 11, causing the temperature at the contact point between the sleeve 12 and / or the anvil 11 and the plate assembly B to rise, which in turn causes the deterioration of the organic layer E.

[0035] Therefore, the present inventors attempted to provide cooling means to the sleeve 12 and the anvil 11 and cool the organic layer E in contact with the sleeve 12 and / or the anvil 11 during the press-fitting step S2 to the friction welding step S3. As a result, it was possible to suppress peeling of the organic layer E. Furthermore, even when the organic layer E was cooled using the sleeve 12 and the anvil 11, friction welding was not hindered and good joint strength was ensured.

[0036] Based on the above findings, in the manufacturing method of organic material layer-coated metal sheet lap joint A according to the first embodiment, the organic material layer E is cooled using a fixing jig that comes into contact with the organic material layer E during the steps from press-fitting step S2 to friction welding step S3. Specifically, when the organic material layer E comes into contact with the sleeve 12, the organic material layer E is cooled using the sleeve 12, and when the organic material layer E comes into contact with the anvil 11, the organic material layer E is cooled using the anvil 11.

[0037] As described above, the organic material layer E may be provided on only one surface of the plate set B, or on both surfaces. Furthermore, when the organic material layer E is provided on only one surface of the plate set B, the organic material layer E may be provided on the anvil 11 side or on the opposite side of the anvil 11. When the organic material layer E is provided only on the anvil 11 side, it is sufficient to cool the organic material layer E using at least the anvil 11. When the organic material layer E is provided only on the sleeve 12 side, it is sufficient to cool the organic material layer E using at least the sleeve 12. When the organic material layer E is provided on both the anvil 11 side and the sleeve 12 side, it is sufficient to cool the organic material layer E using both the anvil 11 and the sleeve 12. Furthermore, when the organic material layer E is provided on only one surface of the plate set B, it is also possible to cool the organic material layer E and the metal plate using both the anvil 11 and the sleeve 12.

[0038] Note that "cooling" means cooling the metal plates to a degree that can suppress the temperature rise due to friction welding. For example, even if the anvil 11 and sleeve 12 are made of an ordinary material, such as steel, some heat transfer occurs from the metal plates to the anvil 11 and sleeve 12 during friction welding. However, because steel cannot sufficiently suppress the temperature rise due to friction welding, such heat transfer does not fall under the category of cooling in this embodiment.

[0039] The cooling means is not particularly limited. One suitable example of the cooling means is to use a metal with high thermal conductivity as the material for the anvil 11 and / or the sleeve 12. For example, by using copper or a copper alloy for the anvil 11 and / or the sleeve 12, heat transfer from the anvil 11 and / or the sleeve 12 to the device body can be promoted, thereby cooling the organic layer E. The thermal conductivity of the material for the anvil 11 and / or the sleeve 12 is preferably 220 W / mK or higher, and more preferably 280 W / mK or higher.

[0040] Another suitable example of the cooling means is to provide the anvil 11 and / or sleeve 12 with cooling mechanisms 111, 121 that use a refrigerant, as shown in FIG. 2. The anvil 11 and / or sleeve 12 may be made of copper or a copper alloy and provided with the cooling mechanisms 111, 121. In FIG. 2, the cooling mechanism 121 is depicted as a device that sprays a refrigerant toward the work table from the rear side of the work table for the anvil 11. The cooling mechanism 121 is depicted as a refrigerant flow path extending from the front side to the back side of the page. However, it should be understood that various configurations can be applied to the cooling mechanisms 111, 121 depending on the application. For example, heat-conductive materials other than copper and copper alloys, Peltier elements, and the like, can also be used as cooling means.

[0041] Furthermore, according to the results of experiments conducted by the present inventors, the sleeve 12 caused peeling of the organic layer E more frequently than the anvil 11. However, as described above, peeling can be prevented by cooling the organic layer E using the sleeve 12. Therefore, when the sheet set B is arranged so that the organic layer E and the sleeve 12 are in contact with each other, the method for manufacturing a lap joint of organic layer-coated metal sheets according to this embodiment is even more advantageous than conventional manufacturing methods.

[0042] Furthermore, as a result of detailed analysis of the peeled portion of the organic layer E, the inventors have found that warping of the second metal plate B2 in contact with the sleeve 12 can also cause peeling of the organic layer E. When the shank C2 of the connection member C is inserted through the second metal plate B2, the second metal plate B2 can warp toward the base end of the shank C2. This can cause the inner edge of the end face of the sleeve 12 that contacts the organic layer E to slightly damage the organic layer E.

[0043] Therefore, a chamfered portion 123 having a radius of 0.1 mm or more may be provided on the inner edge of the end surface of the sleeve 12 that comes into contact with the organic layer E. This eliminates the risk that the inner edge of the end surface of the sleeve 12 will damage the organic layer E, and more effectively prevents peeling of the organic layer E. The chamfered portion 123 preferably has a radius of 0.2 mm or more, and more preferably has a radius of 0.3 mm or more. Note that a typical sleeve 12 is manufactured by means of drilling a rod-shaped material, and the chamfered portion 123 is not formed on the inner edge of the end surface of such a sleeve 12.

[0044] Next, a method for manufacturing a lap joint of organic layer-coated metal sheets according to a second embodiment of the present invention will be described. The method for manufacturing a lap joint of organic layer-coated metal sheets according to the second embodiment includes, as shown in FIG. (S1) a step of fixing a plate set B composed of a plurality of overlapping metal plates to an anvil 11; (S2) a step of press-fitting a connecting member C having a shaft portion C2 and a head portion C1 provided at a base end of the shaft portion C2 into the plate assembly B from the opposite side of the anvil 11 until the first metal plate B1 in contact with the anvil 11 comes into contact with the tip of the shaft portion C2; (S3) frictionally welding the first metal plate B1 in contact with the anvil 11 to the tip of the shank C2, and mechanically joining the second metal plate B2 through which the shank C2 has penetrated by the head C1 to the metal plate to which the shank C2 has been frictionally welded; Here, an organic layer E is disposed on at least the surface of the plate assembly B that contacts the anvil 11, and the organic layer E is cooled using the anvil 11. Hereinafter, the manufacturing method according to the second embodiment will be described in detail in comparison with the first embodiment.

[0045] The method for manufacturing an organic layer-coated metal sheet lap joint according to the second embodiment is essentially the same as the manufacturing method according to the first embodiment. However, in the manufacturing method according to the second embodiment, the process for fixing the sheet pair B to the anvil 11 is not particularly limited. Unlike the first embodiment, the use of a sleeve 12 in the second embodiment is not essential. For example, the sheet pair B may be fixed to the anvil 11 using a fixing jig such as a clamp (not shown in FIG. 3). If the sleeve 12 is not used, the connecting member C can be pressed and joined to any location on the sheet pair B. Furthermore, in the manufacturing method according to the second embodiment, the organic layer E is disposed at least on the surface of the sheet pair B that contacts the anvil 11. Then, the anvil 11 is used to cool the organic layer E disposed on the anvil 11 side.

[0046] Furthermore, preferred aspects of the manufacturing method according to the first embodiment can also be applied to the manufacturing method according to the second embodiment. For example, the organic layer E may be cooled by making the anvil 11 out of copper or a copper alloy and / or by providing the anvil 11 with a cooling mechanism 111, 121 that uses a refrigerant.

[0047] The basic aspects of the manufacturing methods according to the first and second embodiments have been described above. Next, more preferred aspects that are commonly applicable to these methods will be described.

[0048] (Suitable example of metal plate) The type of metal plate is not particularly limited. The materials of the multiple metal plates included in the plate set B may be the same or different. For example, one or more of the multiple metal plates may be steel plates. This can increase the strength of the organic layer-coated metal plate lap joint A. All of the multiple metal plates may be steel plates.

[0049] Note that the rotational force and pressing force required to penetrate the shank C2 of the connecting member C are greater and it takes a longer time to penetrate a steel plate than a soft metal plate such as an aluminum plate. Therefore, when the second metal plate B2 is a steel plate, the temperature of the organic material layer E is likely to rise, and therefore the organic material layer E is likely to peel off. However, in the manufacturing methods according to the first and second embodiments, the organic material layer E is cooled by the anvil 11 and / or the sleeve 12, so that peeling of the organic material layer E can be effectively prevented even if one or more of the multiple metal plates is a steel plate.

[0050] Furthermore, before the press-fitting step S2 is performed, a hole for passing the shank C2 of the connecting member C may be previously formed in the second metal plate B2. This is particularly effective when the second metal plate B2 is made of a hard material such as a steel plate. This allows the press-fitting step S2 to be easily performed. Specifically, the shank C2 of the connecting member C can be passed through in a short time. Furthermore, the shank C2 of the connecting member C can be passed through without rotating the connecting member C. The shape of the hole provided in the second metal plate B2 is not particularly limited as long as it has a diameter smaller than the diameter of the head C1 of the connecting member C. Unlike bolt fastening, the diameter of the hole provided in the second metal plate B2 may be smaller than the thickness of the shank C2 of the connecting member C. This is because the connecting member C is press-fitted into the plate assembly B.

[0051] (Suitable examples of organic layer E) The organic layer E is a surface coating layer containing an organic substance and is used, for example, to improve the corrosion resistance and aesthetics of metal sheet lap joints. One example of the organic layer E is a coating film primarily composed of an organic substance. To further improve the properties of the organic layer E, additives composed of inorganic substances or metals may be added to the organic layer E. Another example of the organic layer E is a coating film using an organic substance as a binder. In this case, even if the organic substance content is low, there is a risk of the organic substance degrading and the organic layer peeling during normal friction welding. There are no particular limitations on the organic substance contained in the organic layer E. However, organic layer E containing an organic substance with a glass transition temperature of 50°C or less is more likely to soften and peel due to heat, making the present invention more applicable. An intermediate layer, such as a plating or a chemical conversion coating, may be further provided between the organic layer E and the metal sheet.

[0052] As described above, the organic layer E is disposed on one or both surfaces of the plate set B. Alternatively, both surfaces of the metal plates included in the plate set B may be coated with the organic layer E, thereby disposing the organic layer E on the mating surfaces of the metal plates inside the plate set B. An adhesive, a sealant, or the like may be applied to the mating surfaces of the metal plates included in the plate set B.

[0053] The configuration of the connection member C and the friction welding conditions are not particularly limited. In the manufacturing methods according to the first and second embodiments, peeling of the organic layer E is prevented by cooling the organic layer E with the anvil 11 and / or sleeve 12. Therefore, the joining conditions are not particularly limited, and conditions can be appropriately adopted depending on the configuration of the multiple metal plates that are the materials to be joined.

[0054] Next, a manufacturing apparatus 1 for an organic substance layer-coated metal sheet lap joint according to a third embodiment of the present invention will be described. The manufacturing apparatus 1 for an organic substance layer-coated metal sheet lap joint according to the third embodiment includes an anvil 11 configured to fix a sheet assembly B made up of a plurality of overlapping metal sheets, a rotary pressing mechanism 13 that presses a connecting member C having a shaft portion C2 and a head portion C1 provided at the base end of the shaft portion C2 against the sheet assembly B from the opposite side of the anvil 11 while rotating the connecting member C about the axis of the connecting member C, and a cylindrical sleeve 12 that is pressed against the sheet assembly B from the opposite side of the anvil 11 to fix the sheet assembly B, the rotation axis of the rotary pressing mechanism 13 being located inside 122 of the sleeve 12, and one or both of the anvil 11 and the sleeve 12 having a cooling means.

[0055] The anvil 11 and the cylindrical sleeve 12 fix the plate set B. In addition, one or both of the anvil 11 and the sleeve 12 has a cooling means capable of cooling the organic layer E provided on the surface of the plate set B. This makes it possible to prevent peeling of the organic layer E. Since the sleeve 12 is more likely to peel off the organic layer E, it is preferable to provide the cooling means on the sleeve 12.

[0056] The cooling means is not particularly limited, but for example, one or both of the anvil 11 and the sleeve 12 may be made of copper or a copper alloy and may themselves serve as the cooling means. Alternatively, the cooling means may be a refrigerant-based cooling mechanism 111, 121 provided on one or both of the anvil 11 and the sleeve 12. Both of these cooling means may also be employed. That is, more preferably, one or both of the anvil 11 and the sleeve 12 are made of copper or a copper alloy and have a refrigerant-based cooling mechanism 111, 121.

[0057] The sleeve 12 may have a chamfered portion 123 with a radius of 0.1 mm or more on the inner edge of the end surface that comes into contact with the organic layer E. This eliminates the risk that the inner edge of the end surface of the sleeve 12 will damage the organic layer E, and makes it possible to more effectively prevent peeling of the organic layer E.

[0058] The rotary pressing mechanism 13 presses the connecting member C, which has a shaft portion C2 and a head portion C1 provided at the base end of the shaft portion C2, against the plate assembly B while rotating it around the axis of the connecting member C from the opposite side of the anvil 11. This allows the connecting member C to rotate relative to the plate assembly B, thereby enabling friction welding. Note that in order to press the connecting member C into the plate assembly B through the cylindrical sleeve 12, the rotation axis of the rotary pressing mechanism 13 must be disposed on the inside 122 of the sleeve 12. The rotary pressing mechanism 13 may also include a gripping portion capable of gripping and rotating the head portion C1 of the connecting member C. On the other hand, if the head portion C1 of the connecting member C has a polygonal hole, the rotary pressing mechanism 13 may simply include a polygonal protrusion having a shape corresponding to the polygonal hole in the head portion C1. The mechanism for pressing the connecting member C while rotating it is not particularly limited, and any known configuration suitable for friction welding can be appropriately adopted.

[0059] The use of the manufacturing apparatus 1 according to the third embodiment is not particularly limited, but it is suitable for carrying out the manufacturing method according to the first embodiment, for example.

[0060] Next, a manufacturing apparatus 1 for an organic substance layer-coated metal sheet lap joint according to a fourth embodiment of the present invention will be described. The manufacturing apparatus 1 for an organic substance layer-coated metal sheet lap joint according to the fourth embodiment includes an anvil 11 configured to fix a sheet assembly B made up of a plurality of overlapping metal sheets, and a rotary pressing mechanism 13 that presses a connecting member C having a shaft portion C2 and a head portion C1 provided at the base end of the shaft portion C2 against the sheet assembly B from the opposite side of the anvil 11 while rotating the connecting member C about the axis of the connecting member C, and the anvil 11 has a cooling means.

[0061] The manufacturing apparatus 1 according to the fourth embodiment is essentially the same as the manufacturing apparatus 1 according to the third embodiment. However, in the manufacturing apparatus 1 according to the fourth embodiment, the means for fixing the plate set B to the anvil 11 is not particularly limited. Unlike the third embodiment, the use of the sleeve 12 in the fourth embodiment is not essential. For example, the manufacturing apparatus 1 may be provided with a fixing jig such as a clamp for fixing the plate set B to the anvil 11. If the sleeve 12 is not used, the connecting member C can be pressed and bonded to any location on the plate set B. Furthermore, in the manufacturing apparatus 1 according to the fourth embodiment, the anvil 11 is used to cool the organic material layer E arranged on the anvil 11 side. Note that if the manufacturing apparatus 1 according to the fourth embodiment does not include the sleeve 12, there is no risk of the organic material layer E arranged on the opposite side of the anvil 11 peeling off.

[0062] The use of the manufacturing apparatus 1 according to the fourth embodiment is not particularly limited, but it is suitable for carrying out the manufacturing method according to the second embodiment, for example. [Example]

[0063] The effects of one embodiment of the present invention will be explained in more detail using examples. However, the conditions in the examples are merely examples adopted to confirm the feasibility and effects of the present invention. The present invention is not limited to these examples. Various conditions may be adopted in the present invention as long as they do not deviate from the gist of the present invention and achieve the object of the present invention.

[0064] Various organic layer-coated metal sheet lap joints were produced by friction welding two steel sheets, as shown below, fixed to an anvil using a sleeve. When the first metal sheet was painted, it was overlapped with an unpainted second metal sheet, and various cooling methods were applied to the anvil to evaluate peeling of the organic layer of the first metal sheet. When the second metal sheet was painted, it was overlapped with an unpainted first metal sheet, and various cooling methods were applied to the sleeve to evaluate peeling of the organic layer of the second metal sheet.

[0065] [Table 1]

[0066] Friction welding was performed at 30 mm intervals, every 10 seconds, for a maximum of 100 points. After welding was completed, the surface of the organic layer-coated metal sheet lap joint was visually inspected to check for peeling of the organic layer. The evaluation criterion was the number of times welding was performed until the first peeling of the coating occurred. - More than 91 bond cycles before the first coating peeling occurs: ◎ The number of times the coating is bonded before peeling occurs is between 21 and 90: - The number of times the coating is bonded before peeling occurs is between 6 and 20: △ - The number of times the coating is bonded before peeling occurs is between 1 and 5: ×

[0067] The sleeve and anvil were made of four types: steel, copper, steel with water cooling, and copper with water cooling. In some experiments, the inner edge of the sleeve, which comes into contact with the organic layer, was chamfered with a radius of 0.1 mm. The evaluation results for the organic layer in contact with the sleeve are shown in Table 2. To obtain the experimental results shown in Table 2, the anvil was made of steel, the sleeve was one of the four types mentioned above, and the plate assembly was assembled in the joining device so that the organic layer was disposed on the surface of the plate assembly in contact with the sleeve. Table 3 shows the evaluation results for the organic layer in contact with the anvil. To obtain the experimental results shown in Table 3, one of the four types of anvils described above was used, the sleeve was made of steel, and the plate assembly was assembled into the joining device so that the organic layer was disposed on the surface of the plate assembly in contact with the anvil. The test results for cases where a chamfer was provided on the sleeve are added in parentheses to Table 2.

[0068] [Table 2]

[0069] [Table 3]

[0070] In the comparative example in which both the sleeve and the anvil were made of steel, peeling occurred very early in both the organic layer on the anvil side and the organic layer on the sleeve side. When the sleeve was made of steel and the anvil was made of copper or had a water-cooling mechanism, peeling of the organic layer on the anvil side was suppressed. Furthermore, when the anvil was made of steel and the sleeve was made of copper or had a water-cooling mechanism, peeling of the organic layer on the sleeve side was suppressed. Furthermore, it was confirmed that providing a chamfered portion on the sleeve prevented peeling of one organic layer in some cases. [Explanation of symbols]

[0071] 1 Manufacturing equipment 11 Anvil 111 Cooling mechanism 12 sleeves 121 Cooling mechanism 122 Inside the sleeve 123 Chamfered part 13 Rotation and pressure mechanism A. Organic layer coated metal plate lap joint B board set B1 First metal plate B2 Second metal plate C Connection member C1 head C2 shaft part D Friction welded part E Organic layer S1 Fixed process S2 Press-fit process S3 Friction welding process

Claims

1. a step of fixing a plate set composed of a plurality of overlapping metal plates to an anvil; a step of press-fitting a connecting member having a shaft portion and a head portion provided at a base end of the shaft portion into the plate assembly from the opposite side of the anvil until a metal plate in contact with the anvil comes into contact with a tip end of the shaft portion; a step of frictionally welding the metal plate in contact with the anvil and the tip of the shank, and mechanically joining the metal plate through which the shank has penetrated by the head to the metal plate to which the shank has been frictionally welded; Equipped with In the fixing step, a cylindrical sleeve is pressed against the plate set from the opposite side of the anvil to fix the plate set to the anvil; In the press-fitting step, the connecting member is passed through the inside of the sleeve and press-fitted into the plate assembly, An organic layer is disposed on one or both surfaces of the plate set, When the organic layer contacts the sleeve, the organic layer is cooled using the sleeve, and when the organic layer contacts the anvil, the organic layer is cooled using the anvil. A method for manufacturing a lap joint of organic layer-coated metal sheets.

2. When the organic layer is in contact with the sleeve, the sleeve is made of copper or a copper alloy and / or the sleeve is provided with a cooling mechanism that uses a refrigerant, thereby cooling the organic layer; When the organic layer is in contact with the anvil, the anvil is made of copper or a copper alloy and / or the anvil is provided with a cooling mechanism that uses a refrigerant, thereby cooling the organic layer. The method for manufacturing a lap joint of organic layer-coated metal sheets according to claim 1 .

3. When the organic layer contacts the sleeve, the organic layer is cooled by providing a cooling mechanism using a refrigerant on the sleeve, and when the organic layer contacts the anvil, the organic layer is cooled by providing a cooling mechanism using a refrigerant on the anvil. The method for manufacturing a lap joint of organic layer-coated metal sheets according to claim 1 .

4. The method for manufacturing a lap joint of organic-substance-coated metal sheets according to any one of claims 1 to 3, characterized in that the organic substance layer and the sleeve are in contact with each other.

5. 5. The method for manufacturing a lap joint of organic layer-coated metal sheets according to claim 4, wherein a chamfer having a radius of 0.1 mm or more is provided on the inner edge of the end face of the sleeve that comes into contact with the organic layer.

6. a step of fixing a plate set composed of a plurality of overlapping metal plates to an anvil; a step of press-fitting a connecting member having a shaft portion and a head portion provided at a base end of the shaft portion into the plate assembly from the opposite side of the anvil until a metal plate in contact with the anvil comes into contact with a tip end of the shaft portion; a step of frictionally welding the metal plate in contact with the anvil and the tip of the shank, and mechanically joining the metal plate through which the shank has penetrated by the head to the metal plate to which the shank has been frictionally welded; Equipped with an organic layer is disposed on at least the surface of the plate assembly that contacts the anvil; Cooling the organic layer using the anvil A method for manufacturing a lap joint of organic layer-coated metal sheets.

7. The organic layer is cooled by making the anvil from copper or a copper alloy and / or by providing the anvil with a cooling mechanism that uses a refrigerant. The method for manufacturing a lap joint of organic layer-coated metal sheets according to claim 6.

8. The organic layer is cooled by providing a cooling mechanism using a refrigerant on the anvil. The method for manufacturing a lap joint of organic layer-coated metal sheets according to claim 6.

9. At least one of the plurality of metal plates is a steel plate. The method for manufacturing a lap joint of organic layer-coated metal sheets according to any one of claims 1 to 8.

10. an anvil configured to fix a plate set made up of a plurality of overlapping metal plates; a rotary pressing mechanism that rotates a connecting member having a shaft portion and a head portion provided at a base end of the shaft portion around the axis of the connecting member from the opposite side of the anvil while pressing the connecting member against the plate assembly; a cylindrical sleeve that is pressed against the plate set from the opposite side of the anvil to fix the plate set; Equipped with a rotation shaft of the rotary pressing mechanism is located inside the sleeve; the sleeve has a cooling means; The sleeve cools the organic layer. Manufacturing equipment for organic layer coated metal sheet lap joints.

11. The cooling means The sleeve itself is made of copper or a copper alloy; and A cooling mechanism using a refrigerant provided in the sleeve 11. The apparatus for manufacturing a lap joint of organic layer-coated metal sheets according to claim 10, wherein one or both of the above is used.

12. 11. The manufacturing apparatus for a lap joint of organic layer coated metal sheets according to claim 10, wherein the cooling means is a cooling mechanism that uses a refrigerant and is provided in the sleeve.

13. The sleeve has a chamfer with a radius of 0.1 mm or more on the inner edge of the end surface that comes into contact with the organic layer.

11. The apparatus for manufacturing a lap joint of organic layer-coated metal sheets according to claim 10.

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