JP2005186683A - Gate for load platform of truck and manufacturing method for gate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gate for a load platform of truck having a fine outside appearance. <P>SOLUTION: The gate for the load platform of the truck has a closed section part 2 formed by bending back the end 21 of a plate so that its tip 22 confronts the body of the plate, wherein the body part of the plate positioned in the neighborhood of the place confronting the tip 22 of the end 21 of the plate and on the side where the closed section part 2 is formed is folded toward the inside of the closed section part 2, and the closed section part 2 is formed by molding through welding of the end 21 of the plate to the inward directed part of the closed section part 2 folded. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a truck bed gate, and more particularly to a truck bed gate characterized by a closed cross-sectional shape formed at both ends of the gate. The present invention also relates to a method for manufacturing the gate.

  As shown in FIG. 7A, a gate is formed around the loading platform of the truck 100 in order to prevent the items loaded on the loading platform from falling. The gate includes a side gate 110 and a rear gate 120, but the shapes are almost the same, and both ends of a thin steel plate are pressed or roll-molded to form closed cross-sectional shapes at both ends. . Thereby, strength and rigidity are improved, and the closed cross-sectional shape portions located at both ends are erected around the loading platform so as to be positioned up and down.

  Then, the structure of the gate and the manufacturing method in the conventional example will be described with reference to FIGS. 7B-1 and 7B-2. As shown in FIG. 7 (b-1), the gate 110 is constituted by a substantially square closed cross-sectional shape portion 111, 112 and a wall surface portion 113 positioned therebetween by refracting the end portion of the steel plate. Yes. And the flange part 111a, 112a of the state by which the bent edge part and the steel plate main body were piled up is formed in the location following the wall surface part 113 from the closed cross-section shape parts 111,112. Then, the gate can be manufactured by welding the flange portions 111 and 112, and other parts such as a hinge can be welded and coated on the gate to be installed on the loading platform. Here, the welding method is performed by any method such as spot welding, mash seam welding, arc welding, or laser welding. In addition, in FIG.7 (b-2), as shown by the arrow, the example welded by spot welding is shown. Patent Document 1 below also discloses an example of a conventional gate manufacturing method.

No. 7-8383

  And as mentioned above, when joining by spot welding, it was necessary to provide a flange part, but by using laser welding or laser brazing welding, it is possible to eliminate the flange part and reduce the weight. is there. An example is shown in FIG. As shown in this figure, the end 121 of the steel plate is bent into a substantially square shape, and its tip 122 is brought into contact with or close to the steel plate itself (wall surface portion 140). And the front-end | tip 122 part and steel plate itself are welded by laser welding etc. as shown in FIG.8 (b).

  At this time, if the gap between the welded part F11, that is, the bent tip of the steel plate and the steel plate itself is large, it is difficult to perform reliable welding. A jig for holding the steel plate is required. In particular, since the member is a plate material, the bent tip may be inclined or wavy. An example of a jig for fixing this without a gap during welding is shown in FIG. As shown in this figure, one jig 131 is required inside the closed cross-sectional shape portion, and the position of the tip portion 122 is fixed by an outer jig indicated by reference numeral 132 that is paired therewith. Moreover, the outer jig | tool shown by the code | symbol 133 is provided, and the clearance gap between the front-end | tip 122 and the wall surface part 140 which is steel plate itself can be adjusted by raising / lowering this.

  However, as described above, fixing with a plurality of jigs takes time during welding, resulting in an increase in manufacturing cost. Further, the closed cross-sectional shape portion may have a length of about 2 [m] at the side gate, so that it is difficult to set a jig.

  Furthermore, the appearance after welding is also affected. For example, as shown in FIG. 9 (a-1), when through welding is performed by laser welding, as shown in FIG. 9 (b), a weld bead F12 which is a through-welded state or a heat affected zone is formed. It will be in the state which can be visually recognized from the opposite side of a welding direction, and the problem that an external appearance deteriorates arises. This is the same even when laser welding is performed on the above-described flange portion 111a, as shown in FIG. 9 (a-2). On the other hand, it is conceivable to control the laser output, focusing position, steel plate gap, steel plate thickness variation, plating amount variation, etc. so that the weld bead is not visible from the outside. Costly and very difficult to realize.

  On the other hand, it is considered necessary for welding with a contact between the tip and the steel plate without any gap, but it is considered necessary for reliable welding, but the steel plate is galvanized to prevent rust. If there is, there is a problem that a welding defect occurs. This is because when galvanized steel sheet is irradiated with laser, porosity (bubble-like internal defects) due to the evaporation expansion of zinc and craters due to blow-off (welding material blows off and opens holes due to the expanded zinc vapor) are generated. is there.

  Therefore, in the present invention, the disadvantages of the above conventional example can be improved. In particular, the appearance can be improved, the gate opening / closing workability can be improved by reducing the weight, the fuel consumption can be improved, and the production cost can be reduced. It is an object of the present invention to provide a truck bed gate and a method for manufacturing the gate.

  Therefore, in the present invention, in a truck bed gate having a closed cross-sectional shape portion formed by recursively bending the end portion of the plate material so that the tip thereof faces the plate body, the vicinity of the portion facing the tip of the end portion of the plate material In addition, the plate body body portion positioned on the closed cross-sectional shape portion forming side is bent toward the inside of the closed cross-sectional shape portion, and the end portion of the plate material is formed on the portion toward the inside of the bent closed cross-sectional shape portion. The closed cross-sectional shape part is molded by welding the above. At this time, the track loading gate is erected almost perpendicularly to the inner bottom surface of the truck loading platform at the location where the end portion of the plate material is welded to the inside of the bent closed sectional shape portion. It is desirable that the structure be formed so as to be substantially perpendicular to the standing direction.

  And the gate shown below which rephrased the said structure may be sufficient. That is, the present invention relates to a track carrier gate having a closed cross-sectional shape portion formed by recursively bending an end portion of a plate material so that the tip thereof faces the plate body, and in the vicinity of a portion facing the tip of the end portion of the plate material And a first bent portion that is bent toward the inside of the closed cross-sectional shape portion so as to be convex on the outside of the closed cross-sectional shape portion on the plate body main body portion located on the forming side of the closed cross-sectional shape portion, And forming a second bent portion that is bent so as to be concave outside the closed cross-section shape portion, and forming it into a step shape, and placing the end portion of the plate material between the first bent portion and the second bent portion. It has a configuration in which a closed cross-sectional shape portion is formed by welding. At this time, in the same manner as described above, the place where the end of the plate material is welded is located between the first bent portion and the second bent portion, and the truck bed gate is against the inner bottom surface of the truck bed. Therefore, it is desirable to form such that it is substantially perpendicular to the standing direction when it is erected almost vertically. And it is still more desirable to make it the structure where the part shape | molded in the said step shape was further bent toward the exterior of the closed cross-section shape part, and was shape | molded in the concave shape.

  Furthermore, the end portion of the plate material is bent back so that the front end thereof faces the main body of the plate material, and the plate body main body portion is located in the vicinity of the position facing the front end of the end portion of the plate member and on the side where the closed cross-sectional shape portion is formed. Bending toward the inside of the closed cross-sectional shape portion, pressing the plate-like end portion toward or close to the bent portion of the closed cross-sectional shape portion, and the stepped portion Even if the gate is manufactured by a method for manufacturing a gate for a truck bed, which includes a step of welding a portion facing the inside of the closed cross-sectional shape portion and a plate-like end portion from the end portion side. Good.

  With the above-described configuration, the welded portion of the closed cross-sectional shape portion formed to increase the strength of the truck bed gate enters the portion from the gate wall surface to the inside of the closed cross-sectional shape portion, that is, the inside of the gate. Since it is formed in the position, the weld bead is hardly visible from the outside, and the appearance is improved. In particular, by welding at a location bent in a direction substantially perpendicular to the standing direction of the gate itself, the weld bead becomes difficult to visually recognize from the outside, and the appearance can be improved. In addition, since the plate material end is welded to the inner portion of the bent closed cross-sectional shape portion, the welding state is more stable than welding facing the plate surface, and positioning before welding is also stable. Welding work becomes easy. Furthermore, by further bending the portion formed in a step shape toward the outside of the closed cross section to form a concave shape, the cross-sectional area of the closed cross-sectional shape portion increases, and the rigidity of the gate can be improved.

  Further, in addition to the above configuration, the end portion of the plate material is brought into contact with the convex portion of the second bent portion, and the end portion is separated from the position located between the first bent portion and the second bent portion. It is desirable to arrange and form the closed cross-sectional shape portion by welding the end portions of the plate material. At this time, it is more desirable to have a configuration in which the flat portion is formed on the convex portion of the second bent portion and the end portion of the plate material is in contact with the flat portion, and moreover, among the end portions of the plate material, It is good to weld between the contact part with a 2nd bending part, and the front-end | tip of the said edge part.

  Thereby, while the position of the edge part of the board | plate material contact | abutted to the 2nd bending part is fixed stably, since a welding location is not a lamination | stacking welding state but a clearance gap is formed in the said welding location, it is welding object Even if the plate material, which is an object, is plated, a space for releasing the gas generated during welding is formed, and poor welding can be suppressed. At this time, the flat portion of the second bent portion is formed, and the end of the plate member is brought into contact with the flat portion by the surface, so that the positioning of the end portion is stabilized and more reliable welding can be performed. Further, by welding between the contact portion and the tip, it is possible to reliably form a gas venting gap that may occur during welding, and to obtain a weld member of uniform quality.

  Further, in addition to the above-described configuration, it is desirable that the end of the end of the plate material is set to have a gap with respect to the plate body facing the tip. Thereby, since the front-end | tip of a board | plate material edge part does not contact | abut to a board | plate material main body, it can prevent welding with respect to the wall surface part which is the said main body, and can suppress that an external appearance is impaired accidentally. . Further, it is possible to suppress welding failure due to the undulation of the end of the plate material end, it is not necessary to design with high product accuracy, and the manufacturing cost can be reduced.

  The gate having the above shape may be formed by welding by laser welding. As a result, compared with spot welding, there is no need to take a wide space between the first bent portion and the second bent portion, which are welded locations, and the end portion of the plate material, and material can be reduced. It is possible to reduce the weight of the product.

  Since the present invention is configured and functions as described above, according to this, since it is possible to form a truck bed gate having a good appearance, it is not necessary to pay attention to special finishing and appearance defects, and the appearance The occurrence of defects can be effectively suppressed, the manufacturing cost can be reduced, and the product can be reduced in weight. Moreover, since it becomes continuous welding, compared with spot welding, the strength and rigidity can be improved. Furthermore, the welding procedure is easy and the manufacturing cost can be further reduced.

  The track welding gate has a closed cross-sectional shape portion, and the closed cross-sectional shape portion is formed by bending an end portion of the plate material and welding the plate material end portion and the plate material body. And the gate of this invention has the characteristics in the welding location of a closed cross-section shape part. The feature is that the portion of the plate material that forms the wall surface when the gate is erected on the truck bed is bent toward the inside of the closed cross-sectional shape portion. The part is welded to the end of the plate material forming the closed cross-sectional shape part. In other words, in the state where the gate itself is erected substantially perpendicularly to the loading platform, the vicinity of the welded portion of the closed cross-sectional shape portion is bent in a substantially horizontal direction with respect to the loading platform, and welding is performed at this portion. Thereby, it is set at a position where the welded part enters the inside of the closed cross section, and in particular, because it is located on a surface substantially parallel to the visual recognition direction, it is suppressed that the welded part is visually recognized when the gate is viewed from the front, The appearance can be improved. Hereinafter, specific examples of the present invention will be described.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing a configuration of a truck bed gate according to the present invention. 2 to 4 are cross-sectional views showing the structure of the closed cross-sectional shape portion that is a part of the gate in this embodiment.

(overall structure)
As described in the above-described conventional example, the truck carrier gate 1 according to the present invention is a side gate or a rear gate standing on the outer periphery of the truck carrier (see FIG. 7). In this embodiment, the side gate will be described as an example, but the rear gate has the same configuration. Hereinafter, it is simply referred to as a gate.

  As shown in FIG. 1, the gate 1 is rotatably installed on a loading platform 101 of a truck (not shown) via a hinge 102. When transporting the product, the product is erected and fixed almost vertically with respect to the cargo bed so that the cargo does not fall. In this FIG. 1, a mode when standing with respect to a loading platform is shown.

  The gate 1 is formed of a single steel plate, and closed cross-sections 2 and 3 are formed at both ends thereof. For the convenience of explanation, the state when the gate 1 is erected on the truck bed is considered, and the closed cross-sectional shape portion located in the upper part of FIG. 1 is called the upper closed cross-sectional shape portion 2 and is located below. Is referred to as the lower closed cross-sectional shape portion 3. And the part located between these, Comprising: In this example, the part formed with one steel plate is called the wall surface part 4. FIG. However, the closed cross-sectional shape portions 2 and 3 may be formed only at one end portion of the gate 1.

  The steel plate forming the gate 1 is galvanized on the surface to prevent rust. And it is comprised with the raw material suitable for press or roll molding, and board thickness. However, the material and plate thickness are not limited to those described above.

(Closed cross section)
The closed cross-sectional shape portions 2 and 3 are formed at both ends of the steel plate constituting the gate 1. Hereinafter, the shape and configuration of the upper closed cross-sectional shape portion 2 will be mainly described. And although the lower closed cross-sectional shape part 3 is also demonstrated, the description is abbreviate | omitted about the same structure.

  First, the cross-sectional shape of the closed cross-sectional shape portion 2 is shown in FIG. As shown in this figure, the end portion 21 of the steel plate is pressed or roll-formed into a substantially square shape, and its tip 22 is bent so as to face the steel plate body itself, that is, the surface of the wall surface portion 4. That is, the tip 22 of the end 21 returns to itself and is bent so as to form a closed section. In addition, since the closed cross-sectional shape part 2 is a thing of a side gate, since it is uniformly formed in the longitudinal direction of a truck bed, it will be uniformly formed in the edge of a steel plate. The rear gate is uniformly formed in the width direction of the truck bed.

  And in the gate in a prior art example, welding is performed in the opposing location of the front-end | tip 22 bent back and a steel plate main body (wall surface part 4), However In this application, it differs as follows. That is, a portion of the steel plate main body near the tip 22 of the end portion 21 of the steel plate, which is located on the side where the closed cross-sectional shape portion 2 is formed (a portion continuing from the wall surface portion 4), The structure is such that the end portion 21 of the steel plate is welded to a portion that is bent toward the inside of the closed cross-sectional shape portion 2 and that is directed toward the inside of the bent closed cross-section. This will be described in further detail below. For convenience of explanation, the four sides forming the substantially square closed cross-sectional shape portion 2 are respectively arranged from the tip 22 side to the first side portion 23, the second side portion 24, the third side portion 25, and the fourth side. It will be referred to as part 26. However, the shape of the closed cross-sectional shape portion 2 is not limited to a quadrangle.

  The first side portion 23 forming the closed cross-sectional shape portion 2 is a side where the tip 22 is located, and a side continuous from the wall surface portion 4 which is a steel plate body facing the tip 22 is a fourth side portion 26. The fourth side portion 26 is formed with a convex portion protruding in the inner direction of the closed cross-sectional shape portion 2, and conversely, when viewed from the outside of the closed cross-section portion, a concave portion 27 is formed. The concave portion 27 is bent in the vicinity of the position opposite to the tip 22 of the end portion 21 so as to extend in parallel with the end portion 21 toward the inside of the closed cross-sectional shape portion 2. That is, the fourth side portion 26 that is the steel plate body is bent so as to be convex on the closed cross-sectional shape portion 2 side on the closed cross-sectional shape portion 2 side with respect to the portion facing the tip 22 of the end portion 21. The bent portion 27 a is bent at a substantially right angle with respect to the wall surface portion 4, that is, the fourth side portion 26. This bent portion is referred to as a first bent portion 27a. Further, the fourth side portion 26 that is bent at the first bent portion 27a and goes toward the inside of the closed cross-sectional shape portion 2 is further bent so as to be concave outside the closed cross-sectional shape portion 2, and the second bent portion 27b. Is forming. In other words, the fourth side portion 26 extending so as to pass in parallel with the end portion 21 from the first bent portion 27 a is bent substantially at a right angle in a direction away from the end portion 21 and extends substantially parallel to the wall surface portion 4. As a result, the shape in the vicinity of the opposite portion of the end portion 21 of the fourth side portion 26 is formed in a step shape so as to enter the inside of the closed cross-sectional shape portion 2. However, the upper closed cross-sectional shape portion 2 described with reference to FIG. 2A is formed in a concave shape because a portion entering the closed cross-sectional shape portion 2 is further bent outward. In this way, the concave portion 27 is bent in a substantially square shape toward the inside of the closed cross-sectional shape portion 2 when viewed from the outside of the fourth side portion 26.

  Here, the length of one side of the closed cross-sectional shape portion 2 is, for example, 30 [mm], the width D1 of the recess 27 is 3 to 5 [mm], and the depth D2 is 5 [mm]. However, this dimension is an example and is not limited to this. Further, the shape of the recess 27 is not limited to a substantially square shape.

  As described above, the concave portion 27 is formed, and the side surface of the concave portion 27, that is, the portion bent from the fourth side portion 26 toward the inside of the closed cross-sectional shape portion 2 (the first bent portion 27 a and the second bent portion 27 b The closed cross-sectional shape portion 2 is closed and molded by welding the end portion 21 of the steel plate constituting the bent first side portion 23 to the step-shaped intermediate portion 27c that is a portion between the closed cross-sectional shape portion 2c. The state of such welding is shown in FIG. As shown in this figure, the laser is supplied by the laser torch L1 while the filler is supplied from the outside of the closed cross-sectional shape portion 2 to the end portion 21 adjacent in parallel to the stepped intermediate portion 27c by the filler supply device L2. By irradiating the beam LB, welding is realized. The configuration of the welded portion at this time will be further described in detail. In addition, in FIG.2 (b), although the case where a filler is supplied and laser welding is illustrated, you may weld by laser brazing so that it may mention later.

  First, the surface located near the tip 22 of the first side 23 and located on the inner side of the closed cross-sectional shape portion 2 is brought into contact with the convex portion of the second bent portion 27b of the concave portion 27. . At this time, the first side portion 23 is formed by being bent from the second side portion 24 so as to be inclined toward the closed cross-sectional shape portion 2 side (left side in FIG. 2A) rather than perpendicular to the wall surface portion 4. Therefore, it is not parallel to the stepped intermediate portion 27 c bent substantially perpendicularly to the wall surface portion 4. Accordingly, the end portion 21 of the steel plate is disposed away from the step-shaped central portion 27c from the position in contact with the convex portion of the second bent portion 27b to the tip 22. The gap D3 between the stepped intermediate portion 27c and the vicinity of the tip 22 of the first side portion 23 at this time may be set to 0.1 to 0.2 [mm], for example. At the time of welding, as shown in FIG. 2B, the second side 24 is pressed to the fourth side 26 side (lower side in FIG. 2B) (see arrow Y1), and the first side By providing a jig 31 that presses the portion 23 toward the third side 25 (left side in FIG. 2B) (see arrow Y2) in contact with the second side 24 and the first side 23, The above-described gap D3 can be appropriately formed at the welding location. In addition, the jig | tool 31 is not limited to one thing, It is comprised by two or more things, and may press a steel plate.

  Further, the length of the first side portion 23 to the tip 22 is such that the tip 22 does not contact the wall surface portion 4 when the closed cross-sectional shape portion 2 is formed, and a gap D4 is formed with respect to the wall surface portion 4. Length. The gap D4 is, for example, 2 to 3 [mm]. Here, the value of the gap D4 is not limited to this. Further, the gap D3 between the stepped intermediate portion 27c and the tip 22 of the end portion 21 is not limited to the above value.

  Then, with reference to FIG. 3, the structure of the lower closed cross-sectional shape part 3 formed in the edge part on the opposite side of the said steel plate is demonstrated. FIG. 3A shows a cross-sectional shape of the lower closed cross-sectional shape portion 3, and FIG. 3B shows a state during welding.

  The lower closed cross-sectional shape portion 3 has substantially the same configuration as the upper closed cross-sectional shape portion 2 described above, but a concave portion 27 (see FIG. 2A) formed in the fourth side portion 26 is formed. Different in that it is not. And the 4th side part 26 of this closed cross-section shape part 3 is formed in the step shape by the bending parts 28a and 28b similar to the 1st, 2nd bending parts 27a and 27b mentioned above. That is, the fourth side portion 26 is bent in the closed cross-sectional shape portion 3 in the vicinity of the portion facing the tip 22 of the steel plate, and the fourth side portion 26 is closed with respect to the wall surface portion 4 that is a steel plate body. The step portion 28 is formed on the inner side of the shape portion 3.

  And as shown in FIG.3 (b), the front-end | tip 22 vicinity of the edge part 21 of the 1st edge part 23 is set to the step-shaped intermediate part 28c located between the 1st bending part 28a and the 2nd bending part 28b. The closed cross-sectional shape portion 3 can be molded by bringing the portions close to each other in parallel and welding the portions. In the example shown in FIG. 3B, the case where welding is performed by irradiating the laser beam LB while supplying the brazing material from the end portion 21 side by the brazing material supply device L3 is shown. In such a case, a bead due to the heat-affected zone F2 due to the laser beam appears on the side opposite to the laser beam irradiation side, that is, on the outer side of the closed cross-sectional shape portion 3 of the stepped intermediate portion 28c. Since it is a part which is hard to visually recognize, it is suppressed that an external appearance is impaired.

  In addition, the structure in a welding location, for example, the end part 21 is made to contact | abut to the 2nd bending part 28b, and the front-end | tip 22 is spaced apart from the step-shaped intermediate part 28c (the gap D3 is formed). Since the front end 22 is set to a length that does not contact the wall surface portion 4 (to form the gap D4) and the like, it is the same as in the case of the upper closed cross-sectional shape portion 2 described above, and thus the description thereof is omitted. Further, the welding method is not laser brazing, but may be laser welding using a filler as in the case of the upper closed cross-sectional shape portion 2.

(Production method)
Next, the manufacturing method of the above-mentioned closed cross-sectional shape part 2 is demonstrated. The upper closed cross-sectional shape portion 2 will be described below as an example, but basically the same applies to the lower closed cross-sectional shape portion 3.

  First, as shown in FIG. 2, the end portion 21 of the steel sheet is bent into a substantially quadrangular shape so as to form a closed cross section, as shown in FIG. At the same time or before and after this, the concave portion 27 (stepped portion 28 in the case of the lower side) is also molded. At this time, the direction in which the stepped intermediate portion 27c extends inside the closed cross-sectional shape portion 2 and the direction in which the first side portion 23 extends are not parallel but molded. That is, the stepped intermediate portion 27 c is bent so as to extend in a substantially vertical direction with respect to the wall surface portion 4, and the first side portion 23 is bent so as to be inclined toward the closed cross-sectional shape portion 2 side with respect to the wall surface portion 4. And molded. In addition, the length of the first side portion 23 is adjusted and bent so that the tip 22 of the end portion 21 forms a gap D4 with respect to the wall surface portion 4.

  Subsequently, a jig 31 for pressing the first side portion 23 and the second side portion 24 in the internal direction of the closed cross-sectional shape portion 2 (see arrows Y1 and Y2 in FIG. 2B) is disposed, The convex portion of the second bent portion 27b that forms the concave portion 27 (the stepped portion 28 in the case of the lower side) is a portion on the inner side of the closed cross-sectional shape portion 2 near the tip 22 of the end portion 21 of the steel plate. Abut. Then, the tip 22 side of the end 21 is in a state of being disposed with a gap D3 from the stepped intermediate portion 27c.

  And in this state, by irradiating the laser beam LB with the laser torch L1 between the contact portion with the second bent portion 27a and the tip 22 of the end portion 21 from the end portion 21 side of the steel plate. Then, the stepped intermediate portion 27c and the end portion 21 are welded.

  By molding the closed cross-sections 2 and 3 as described above, the truck bed gate 1 as shown in FIG. 1 can be manufactured. In addition, the truck bed gate 1 in this figure is extended in the near direction and the depth direction perpendicular to the paper surface of the figure.

  Then, by molding as described above, the welded portion of the closed cross-sectional shape portions 2 and 3 formed to increase the strength of the gate 1 extends from the surface of the gate 1 to the inside of the closed cross-sectional shape portions 2 and 3. Since it is formed in the part which goes to, ie, the position which entered the inside of a closed section shape part, it becomes difficult to visually recognize a weld bead from the outside, and it becomes a gate excellent in appearance. In particular, the bending direction of the stepped intermediate portions 27 c and 28 c that are welding locations is substantially perpendicular to the standing direction when the gate 1 is erected on the cargo bed 101, in other words, substantially horizontal to the cargo bed 101. By setting the direction, the weld bead appears on a surface substantially parallel to the viewing direction, and the bead is more difficult to visually recognize from the outside. This state is shown in FIG. 1 and FIG. 2 (b). When the gate 1 standing on the track is viewed from the outside lateral direction (see reference numeral E), it is due to through welding formed at the welding location. It can be seen that the bead F1 and the heat-affected zone F2 by laser brazing are formed at positions that are difficult to visually recognize (see arrows from reference E). Due to such an improvement in appearance, it is not necessary to pay attention to special finishing and appearance defects, and occurrence of appearance defects can be effectively prevented. In addition, when laser brazing is performed, the end of the steel plate can be reliably closed, and water or the like can be prevented from entering the closed cross-sectional shape portions 2 and 3, so that it is taken as a rust prevention measure. The application of the sealant can be abolished. From the above, an increase in manufacturing cost and labor can be suppressed, and an increase in weight can also be suppressed. Furthermore, since continuous welding is performed, the strength and rigidity of the closed cross-sectional shape portion can be improved as compared with the conventional spot welding. For example, as shown in FIG. 7A, the vehicle height is low such that the height H1 from the ground to the loading platform is 640 [mm], and the height H2 from the top of the gate 1 is 930 [mm]. If the gate is equipped on a truck, the above effect is more remarkable.

  Furthermore, since welding is performed in a state close to lap welding at the welding location, the strength of the welding between the end surface which is the tip 22 of the end portion 21 and the plate surface which is the wall surface portion 4 which is performed in the conventional example is However, it is possible to realize strong welding with higher reliability than such a welded state. At this time, since the end portion 21 can be brought into contact with the second bent portion 27b and the end portion 21 can be positioned, the positioning before welding can be stably performed, and the welding operation is facilitated. . Then, by performing such welding by laser welding, it is not necessary to take a wide proximity portion between the stepped intermediate portion 27c that is a welding location and the end portion 21 as compared with spot welding, thereby reducing the material. It is possible to reduce the weight of the product.

  Further, since the gap D3 is formed between the members at the welding location, that is, between the stepped intermediate portion 27b and the end portion 21, even if the plate material that is the object to be welded is plated, the gap is generated. A space for escaping gas is formed, and poor welding can be suppressed. Moreover, by forming the gap D4 so that the front end 22 of the steel plate does not come into contact with the wall surface portion 4, it is possible to suppress the end portion 21 and the wall surface portion 4 from being welded, and to prevent the appearance from being accidentally impaired. be able to. Furthermore, welding failure due to the undulation of the tip 22 of the end portion 21 can be suppressed, and it is not necessary to design with high product accuracy, and the manufacturing cost can be reduced. This also helps to release the gas during welding by the above-described plating.

  Since the upper closed cross-sectional shape portion 2 has a larger closed cross-sectional area than the lower closed cross-sectional shape portion 3, in addition to the effects described above, the gate rigidity can be improved.

(Modification)
Here, a modified example of the closed cross-sectional shape portion 2 of the gate 1 which is a characteristic part of the present invention will be described with reference to FIG. In addition, although the upper closed cross-section shape part 2 mentioned above is mentioned as an example and demonstrated, you may apply to the lower closed cross-section shape part 3, and may apply to the closed cross-section shape part of a different shape.

  In the closed cross-sectional shape portion 2 shown in FIG. 4A, the shape of the concave portion 27 is different from that described above. Specifically, the shape of the second bent portion 27b forming the concave portion 27 is different, and a flat portion is formed in the convex portion of the bent portion 27b. This is shown in the enlarged view of FIG. And by making this plane part 27b contact | abut the surface inside the closed cross section of the steel plate edge part 27b, positioning of the edge part 21 at the time of welding is stabilized more, and more reliable welding can be performed.

  Next, a second embodiment of the truck bed gate 10 according to the present invention will be described with reference to FIGS. FIG. 5 is a cross-sectional view showing the configuration of the closed cross-sectional shape portion 5 in this embodiment, and FIG. 6 is a cross-sectional view showing the configuration of the gate provided with the closed cross-sectional shape portion 5 shown in FIG.

  The closed cross-sectional shape portion 5 formed on the truck bed gate 10 in the present embodiment is different from that described above, and has the shape shown in FIG. The configuration will be described in detail.

  First, similarly to the above-described closed cross-sectional shape portions 2 and 3, the end portion 51 of the steel plate is bent so that the tip 52 thereof faces the wall surface portion 4 which is the steel plate body to form a closed cross section. And although the shape of this closed cross section is a substantially square shape, in the vicinity of the location where the front-end | tip 52 of a steel plate main body opposes, it has become the shape where a part of the substantially square closed cross section spread further to the wall surface part 4 side. . Here, for convenience of explanation, each side forming the closed cross-sectional shape portion 5 is separated from the side where the tip 52 of the end portion 51 is located, the first side portion 53a, the second side portion 53b, the third side portion 53c, The fourth side 53d and the fifth side 53e are called, and the side continuous from the fifth side 53e to the wall surface 4 is called the sixth side 53f.

  The sixth side portion 53f has a shape indicated by a dotted line 53f ′ when the steel plate has a shape extending substantially linearly from the wall surface portion 4 to the fifth side portion 53e. In the embodiment, such a portion is bent in the inner direction of the closed cross-sectional shape portion 5, that is, in the direction in which the second side portion 53b is located, and the concave portion 57 is formed as viewed from the outside. Therefore, similarly to the closed cross-sectional shape portion 2 in Example 1 described above, the portion on the forming side of the closed cross-sectional shape portion 5 near the position where the tip 52 of the end portion 51 of the steel plate body faces is a closed cross-sectional shape portion. 5 is bent toward the inside (first bent portion) and is located in parallel with the first side portion 53a, and is further bent in a direction away from the first side portion 53a (second bent portion). And welding with the edge part 51 is performed in the location (location between a 1st bending part and a 2nd bending part) of the recessed part 57 located in parallel with the 1st side part 53a. At this time, as in the case of the first embodiment, the closed cross-section inner side portion of the first side portion 53a where the tip 52 of the end portion 51 is located is used as the convex side portion of the second bent portion of the concave portion 57. By abutting, positioning in the vicinity of the tip 52 that is a welding location is stabilized.

  In addition, the specific structure of the location located in parallel is the same as that in the case of the first embodiment. For example, a gap may be set between the tip 52 and the steel plate main body (wall surface portion 4), or a gap may be set between the tip 52 of the end 51 located near the welded portion and the recess 57. Moreover, it is good to form the convex side part of the 2nd bending part of the recessed part 57 contact | abutted to the 1st edge part 53a in planar shape.

  FIG. 6 shows the gate 10 formed with the closed cross-sectional shape portion 5 formed in this way on the upper side. A lower closed cross-sectional shape portion 3 according to the first embodiment is formed below the wall surface portion 4.

  The gate 10 shown in this figure is in a state where it is erected on a truck bed (not shown), but the welded portion F3 enters the inside of the closed cross-sectional shape part 5, and further, with respect to the erection direction of the gate 10. Therefore, it is difficult to visually recognize from the outside, and the appearance can be improved as described above. This eliminates the need to pay attention to special finishing and appearance defects, can effectively prevent the appearance of defects, and when laser brazing is performed, the end of the steel plate can be reliably closed. It can prevent the entry of water etc. into the closed cross-sectional shape part, so the application of sealing agent as a rust prevention measure can be abolished, the manufacturing cost can be reduced and the weight can be reduced. Can also be planned. Moreover, since it becomes a continuous welding, compared with the case of the conventional spot welding, the improvement of the intensity | strength and rigidity of a closed cross-section shape part can be aimed at.

  Since the gate for a truck bed according to the present invention has a good appearance, it is not necessary to pay attention to special finishing processing and appearance defects, and the manufacturing cost can be reduced and the weight can be reduced. It is suitable for equipment and can be used industrially.

It is sectional drawing which shows the structure of the truck carrier gate in Example 1. FIG. FIG. 2A is a cross-sectional view showing the configuration of the upper closed cross-sectional shape portion of the gate in the first embodiment, and FIG. 2B is an explanatory view showing a state during welding. FIG. 3A is a cross-sectional view showing a configuration of the lower closed cross-sectional shape portion of the gate in the first embodiment, and FIG. 3B is an explanatory view showing a state at the time of welding. 4A is a cross-sectional view showing a configuration of a modification of the upper closed cross-sectional shape portion of the gate in the first embodiment, and FIG. 4B is a partially enlarged cross-sectional view thereof. It is sectional drawing which shows the structure of the closed cross-sectional shape part of the truck carrier gate in Example 2. FIG. It is sectional drawing which shows the structure of the gate for truck loading platforms provided with the closed cross-sectional shape part disclosed in FIG. FIG. 7 is a diagram for explaining a conventional truck bed gate. FIG. 7A shows an overall view of the track. FIG. 7B-1 shows a sectional perspective view of the side gate, and FIG. 7B-2 shows a front view thereof. FIG. 8 is a diagram showing a configuration of a closed cross-sectional shape portion formed in a conventional gate. FIG. 8A is a sectional view showing the structure, and FIG. 8B is a view showing a state when welding. FIG.8 (c) is a figure which shows a mode when the jig | tool used when welding is arrange | positioned. FIG. 9 is a diagram showing a configuration of a closed cross-sectional shape portion formed in a conventional gate. FIGS. 9A-1 and 9A-2 are cross-sectional views showing the configuration and the state when welded. FIG.9 (b) is a cross-sectional perspective view which shows the mode of a weld bead.

Explanation of symbols

1,10 Truck carrier gate 2 Closed section (upper side)
3 Closed section (bottom)
4 Wall surface portion 5 Closed cross-sectional shape portion 21 End portion 22 Tip portion 23 First side portion 24 Second side portion 25 Third side portion 26 Fourth side portion 27 Recessed portion 28 Stepped portions 27a and 28a First bent portions 27b and 28b First Two bent portions 27c, 28c Stepped intermediate portion 31 Jig 51 End portion 52 Tip 53a First side portion 53b Second side portion 53c Third side portion 53d Fourth side portion 53e Fifth side portions 53f, 53f ′ Sixth side Portion 57 Recess 101 Loading platform F1, F2, F3 Weld bead E View point

Claims (11)

In the gate for a truck bed having a closed cross-sectional shape portion formed by recursively bending the end portion of the plate material so that the tip thereof faces the plate material body,
The plate material main body portion located near the tip of the end portion of the plate material and located on the formation side of the closed cross-sectional shape portion is bent toward the inside of the closed cross-sectional shape portion, and the bent A gate for a truck bed, wherein the closed cross-sectional shape portion is formed by welding an end portion of the plate material to a portion facing the inside of the closed cross-sectional shape portion.   A track cargo bed gate is erected almost perpendicularly to the inner bottom surface of the truck cargo bed at a portion toward the inside of the bent closed cross-sectional shape portion where the end of the plate is welded. 2. The truck bed gate according to claim 1, wherein the gate is formed so as to be substantially perpendicular to the standing direction. In the gate for a truck bed having a closed cross-sectional shape portion formed by recursively bending the end portion of the plate material so that the tip thereof faces the plate material body,
In the vicinity of the portion facing the tip of the end portion of the plate material and on the plate body main body portion located on the forming side of the closed cross-section shape portion, the closed cross-section shape portion of the closed cross-section shape portion is convexed outside the closed cross-section shape portion. While forming a first bent portion bent toward the inside and a second bent portion bent so as to be concave outside the closed cross-section shape portion, it is molded into a step shape,
A truck bed gate characterized in that the closed cross-sectional shape portion is formed by welding an end portion of the plate member between the first bent portion and the second bent portion.   The location between the first bent portion and the second bent portion, where the end of the plate is welded, is such that the truck bed gate is substantially perpendicular to the inner bottom surface of the truck bed. 4. The truck bed gate according to claim 3, wherein the gate is formed so as to be substantially perpendicular to the standing direction when it is erected.   5. The truck bed gate according to claim 3, wherein the step-shaped portion is further bent toward the outside of the closed cross-sectional shape portion and formed into a concave shape.   The end portion of the plate material is brought into contact with the convex portion of the second bent portion, and the end portion is arranged apart from the position located between the first bent portion and the second bent portion, The gate for a truck bed according to claim 3, 4 or 5, wherein an end portion of the plate member is welded to form the closed cross-sectional shape portion.   The gate for a truck bed according to claim 6, wherein a flat portion is formed on the convex portion of the second bent portion, and an end portion of the plate member is brought into contact with the flat portion.   The gate for a truck bed according to claim 6 or 7, wherein welding is performed between a contact portion with the second bent portion and an end of the end portion of the plate material. .   The gate for a truck bed according to claim 3, 4, 5, 6, 7 or 8, wherein a tip of an end portion of the plate material is set so as to have a gap with respect to a plate body main body facing the tip. .   The truck bed gate according to claim 3, 4, 5, 6, 7, 8, or 9, wherein the welding is laser welding. A plate body main body located near the portion facing the tip of the end of the plate and on the side where the closed cross-sectional shape portion is formed is bent back so that the end of the plate is opposed to the plate main body. Bending toward the inside of the closed cross-sectional shape part;
A step of pressing the plate-like end portion toward or in close proximity to the bent portion toward the inside of the closed cross-sectional shape portion; and
Welding the portion of the stepped portion toward the inside of the closed cross-sectional shape portion and the plate-like end portion from the end side;
A method for manufacturing a gate for a truck bed, comprising:

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