JP5284881B2 - Handrail joint material - Google Patents

Description

  The present invention relates to a continuous handrail constructed by placing a resin headboard on a headboard (metal base) that constitutes the core material of the handrail. More specifically, for example, the present invention is attached to a wall surface along a staircase with an inclination. It is related with the handrail joint material which connects the edge part of the cap board holder and the end part of the cap board holder attached horizontally to the wall surface of the stair landing, and constitutes the vertical bending part of the handrail.

  When installing continuous handrails in hallways and stairs, in particular, stairs have many corners. Conventionally, handrail metal bases have been bent in advance at the factory, or special corner materials are used for the handrail bends. It was necessary to prepare and construct the bent part of the handrail. When bending the metal base in advance, the bent part of the handrail can be finished beautifully, but if the handrail has a long working distance and there are many bent parts of the handrail, it is necessary to perform a great deal of processing on the metal base There is. In addition, if the bent portion of the handrail is to be constructed using a corner material composed of a flexible material or a coil spring, or a corner material that can be bent around the rotation axis, bending of the metal base is not required. Therefore, it is easy to install handrails, but it is necessary to prepare special corner materials, which not only increases the construction cost, but also creates gaps and irregularities in the bent part of the handrail, resulting in loss of continuity of the handrails. May be.

  Japanese Patent Laying-Open No. 2005-2758 discloses a continuous handrail constructed by covering a metal headpiece (metal base) with a resin headboard. In this handrail, the metal core material 1 is arranged on the straight portion of the handrail, and, like the metal core material 1, the soft core or the soft shape of the shape in which the covering material 6 having a substantially C-shaped section can be fitted to the curved portion of the handrail. A resin core material 10 made of a semi-rigid thermoplastic synthetic resin is disposed, the resin core material 10 is bent into a predetermined arc, and is connected and fixed to the metal core material 1, and the metal core material 1 and the resin core material 10 are connected. Cover with a long covering material (headwood) 6.

  Japanese Patent Application Laid-Open No. 2004-131966 discloses a universal corner tool for forming a bent portion on a handrail. This universal corner tool includes a handrail main body 2 made of synthetic resin, and the handrail main body 2 includes a shaft body 7 that can be expanded and contracted, and a plurality of flanges 6 that are integrally formed with the shaft body 7 at an arbitrary interval. A connecting shaft portion 3 extended at both ends of the shaft body 7 and a boss member 4 made of synthetic resin having an outer diameter equal to that of the flange 6 and formed integrally with the connecting shaft portion 3. A flexible tube 5 is fitted on the outer side of each flange 6 and the boss member 4.

  The resin core material 10 made of thermoplastic synthetic resin for handrails disclosed in Japanese Patent Application Laid-Open No. 2005-2758 is used after being curved into a desired arc in a factory or the like. It is not easy to change the bending angle of the resin core material 10 at the construction site.

  In the universal corner tool disclosed in Japanese Patent Application Laid-Open No. 2004-131966, each part of the shaft body 7 is independently extendable and bendable in all directions (see paragraph 0019), so the degree of freedom of deformation of the shaft body 7 May become excessive, which may reduce the workability of continuous handrails.

JP 2005-2758 A JP 2004-131966 A

  The object of the present invention is a handrail joint that can be used to construct a bent portion in the vertical direction of a handrail, has high workability at the construction site, and can ensure the continuity of the handrail. To provide materials.

  Another object of the present invention is to provide a handrail joint material that can be molded integrally as a single resin part using a mold having a simple structure, and can reduce material costs. There is.

  Still another object of the present invention is to bend and mold in advance to a general bending angle at a bending portion in the vertical direction of the handrail, and in the vertical range within the angle range regulated in advance with reference to this bending angle. The object is to provide a handrail joint material that can be bent only.

  Still another object of the present invention is a handrail joint that is connected to a headboard (metal base) that constitutes the core material of the handrail and can be covered with a resin headboard that is continuous from the headboard. To provide materials.

  In order to achieve the above object, a handrail joint material according to the present invention includes a first connection end connected to one handrail, a second connection end connected to the other handrail, a first and a second connection end. A bridging portion extending between the second connecting ends and integrated with the first and second connecting ends. This bridging portion has an upper surface and a lower surface, and has a plate-like form as a whole so that bending deformation is possible only in the direction of the upper surface and the lower surface. The bridging portion is also oriented in the direction of the upper surface or the lower surface so that the axis of the first connecting end and the axis of the second connecting end intersect at a predetermined angle within the plane through which these axes pass. Curved in advance. Furthermore, a rib is integrally formed on the bridge portion, and a support surface that holds the shape of the headboard by contacting the inner surface of the headboard and a locking portion that locks the edge of the headboard are formed on the rib. And the upper surface and lower surface of a bridge | crosslinking part are exposed along this rib.

  As an embodiment, the handrail joint material of the present invention can have a plurality of plate-like ribs extending in the vertical direction from the upper surface and the lower surface and extending in a direction crossing the bridge portion. These plate-like ribs are arranged at a predetermined interval between the first and second connecting ends. Among these plate-like ribs, gaps extending along the pair of plate-like ribs are formed between a pair of plate-like ribs adjacent to each other in the direction of the first and second connecting end portions. Each of these voids extends in a direction crossing the bridging portion, and the upper and lower surfaces of the bridging portion can be exposed inside these voids. Then, a convex curved surface that abuts the inner surface of the headboard and maintains the shape of the headboard is formed continuously with the side surfaces of these plate-like ribs and the side surface of the bridging portion, and the locking for locking the edges of the headboard The part can be formed at one or both end edges of the convex curved surface.

  As another embodiment, the handrail joint material of the present invention extends between the first and second connecting end portions along both side edges of the bridging portion, and faces each other across the bridging portion. There may be a pair of side wall ribs located. These side wall ribs extend in the vertical direction from the upper surface and the lower surface of the bridge portion. The upper and lower surfaces of the bridging portion can be exposed between these side wall ribs. Further, a convex curved surface that contacts the inner surface of the headboard and maintains the shape of the headboard is formed so as to be continuous with the outer surface of the side wall rib and the side surface of the bridge portion. Furthermore, the latching | locking part which latches the edge of a headboard is formed in the edge part of one or both of a convex curved surface. A plurality of grooves extending from the edge of the side wall rib on the upper surface side of the bridging portion toward the upper surface of the bridging portion are formed in these side wall ribs, and further, the edge of the side wall rib on the lower surface side of the bridging portion A plurality of grooves extending from the surface toward the lower surface of the bridge portion are formed.

  In the handrail joint material of the present invention, the first connection end portion and the second connection end portion of the joint material are connected in advance by a bridging portion that is curved and formed in a direction in which the handrail is connected. Therefore, when the first connecting end of the joint material is connected to one handrail and the second connecting end is connected to the other handrail, the bridge portion needs to be bent and deformed. The amount of bending deformation can be reduced. Moreover, this bridge | bridging part has a plate-shaped form as a whole so that bending deformation is possible only in the direction of the upper surface and the lower surface. That is, the joint material cannot be bent and deformed in directions other than the directions of the upper surface and the lower surface of the bridge portion. Therefore, the bending work of the joint material is simplified, and the workability of the bent portion of the handrail at the construction site is improved and the construction time can be shortened in combination with the decrease in the bending deformation amount of the bridge portion.

  In addition, a rib is integrally formed on the bridging portion of the joint material of the present invention, and a support surface that abuts the inner surface of the headboard and maintains the shape of the headboard, and a hook that locks the edge of the headboard. Since the section is formed, the headboard can be continuously covered with the handbag head and the joint material of the present invention. Therefore, it is possible to avoid loss of continuity of the handrail due to the occurrence of gaps and irregularities at the joint between the handrail and the joint material of the present invention.

  Since the joint material of the present invention can expose at least a part of the upper surface and the lower surface of the bridging portion along the rib formed on the bridging portion, bending deformation of the bridging portion is inhibited by forming the rib. There is nothing. Furthermore, by restricting the area, shape, and position of the exposed portions of the upper and lower surfaces of the bridging portion, the range in which the bridging portion can be bent and deformed can be regulated.

  Since the joint material of the present invention can be formed as a single member from a synthetic resin material such as polypropylene, the material cost can be kept relatively low. In addition, if the joint material of the present invention is manufactured with a general two-way punch, the production cost can be kept low.

  Since the joint material of the present invention is composed of a single member, it can be easily managed at the construction site and handled.

  And if the joint material of the present invention is frequently used, the portion of the continuous handrail that needs to be bent in advance at the factory is reduced, so the bending work at the factory is reduced and the continuous handrail is reduced. Manufacturing costs and construction costs can be reduced.

  In addition, since there is a limit to the bending deformation amount of the bridging portion of the joint material of the present invention, in order to allow the joint material of the present invention to cope with more bent portions of handrails, in other words, more bending. In order to be able to correspond to the angle, the crossing angle of the axis of the first connecting end and the axis of the second connecting end is 140 degrees, which is a relatively large number of construction examples. It is desirable to provide an adjustment range of about ± 30 degrees by utilizing the bending of the part.

FIG. 1 is a perspective view of a handrail connected by a joint material curved upward. FIG. 2 is a perspective view of a handrail connected by a joint material curved downward. FIG. 3 is a perspective view of the joint material according to the first embodiment of the present invention and two handrail metal bases (caps) connected by the joint material as shown in FIG. (First embodiment) FIG. 4 is a side view of the joint material of FIG. (First embodiment) FIG. 5 is a longitudinal sectional view of the joint material of FIGS. 3 and 4. (First embodiment) FIG. 6 is a side view of a handrail when two handrail metal bases (headboard holders) are connected by the joint material of FIGS. 3 to 5, and a part of the headboard covered with the joint material and the handrail base. It is the side view which notched. (First embodiment) FIG. 7 is a cross-sectional view taken along the line AA of the handrail of FIGS. (First and second embodiments) FIG. 8 is a cross-sectional view taken along the line BB of the joint material of FIGS. (First embodiment) FIG. 9 is a side view of the joint material showing the finely adjustable deflection angle of the joint material of the present invention. FIG. 10 is a perspective view of the joint material according to the first embodiment of the present invention and two handrail metal bases (caps) connected by the joint material as shown in FIG. (First embodiment) FIG. 11 is a side view of a handrail when two handrail metal bases (caps) are connected by the joint material of FIG. 10, and a part of the headboard covered with the joint material and the handrail metal base is cut. FIG. (First embodiment) FIG. 12 is a perspective view of the joint material of the second embodiment of the present invention. (Second embodiment) FIG. 13 is a side view of the joint material of FIG. (Second embodiment) FIG. 14 is a longitudinal sectional view of the joint material of FIGS. 12 and 13 (second embodiment). FIG. 15 is a side view of a handrail when two handrail metal bases (caps) are connected by the joint material of FIG. 12, and a part of the headboard covered with the joint material and the handrail metal base is cut. FIG. (Second embodiment) FIG. 16 is a cross-sectional view taken along line CC of the joint material of FIGS. 13 and 14. (Second embodiment) 17 is a perspective view of the joint material according to the modification of the joint material in FIG. 12, and is a perspective view of the joint material having a curved portion curved in a direction opposite to the bending direction of the joint material in FIG. 12. (Second embodiment) FIG. 18 is a side view of a handrail when the two handrail metal bases (caps) are connected by the joint material of FIG. 17, and is a side view in which a part of the headwood covered with the joint material and the handrail metal base is cut away. It is. (Second embodiment)

  A joint material for constructing a corner portion bent in the vertical direction among the corner portions of the continuous handrail is constituted by a single member made of polypropylene, which is integrally formed using a two-way punching die.

  1 and 2 show the corner portion of the continuous handrail bent in the longitudinal direction. FIG. 1 shows a handrail corner 2 formed at the ascending entrance of the stairs 1, and the corner 2 is installed along the stairs 1 with a handrail 4 installed horizontally on the wall of the landing 3. It is formed between the handrails 5. FIG. 2 shows a handrail corner 6 formed at the exit of the stairs 1, and the corner 6 is installed along the stairs 1 with the handrail 8 installed horizontally on the wall of the landing 7. It is formed between the handrails 9. The corner portions 2 and 6 are both corner portions that are bent in the vertical direction.

  3 to 6 show the joint material 10 of the first embodiment of the present invention. The joint material 10 is used for constructing the corner portion 2 shown in FIG. The joint material 10 is composed of a single component made of polypropylene. In the joint material 10, the first connecting end portion 11 and the second connecting end portion 12 are integrally connected by the bridging portion 13, and a plurality of ribs 16 a and 16 b are integrally formed on the upper surface 14 and the lower surface 15 of the bridging portion 13. Is formed.

  As shown in FIGS. 3 and 7, the first connecting end 11 and the second connecting end 12 have a cross-shaped cross section. The first connecting end portion 11 is inserted into the cross-shaped hollow hole 17 b of the cap stand 17 from the end 17 a of the cap stand (metal base) 17 of the handrail 4, and is attached to the cap stand 17 by the set screws 18 and 18. It is fixed (see FIG. 6). The second connecting end 12 is inserted into the cross-shaped hollow hole 19 b of the headboard holder 19 from the end 19 a of the headboard holder (metal base) 19 of the handrail 5. 19 (see FIG. 6). The cap holders 17 and 19 are made of an extruded material of an aluminum alloy.

  In FIG. 6, reference numeral 21 indicates a bracket for fixing the headboard receiver 17 to the wall surface W, and reference numeral 22 indicates a bracket for attaching the headboard receiver 19 to the wall surface W. Reference numerals 23 and 24 are bolts for fixing the brackets 21 and 22 to the wall surface W. Reference numeral 25 indicates a headboard that continuously covers the headboard receiver 17, the joint material 10, and the headboard receiver 19. The headboard 25 is made of a flexible synthetic resin and has a surface 25a that is easy to touch.

  As shown in FIG. 7, the cap 25 has a tubular shape as a whole. The cap 25 is supported by the caps 17 and 19 with its inner peripheral surface 25b in close contact with the four support surfaces Sa formed on the outer surfaces of the caps 17 and 19, respectively. As shown in FIG. 3, these support surfaces Sa are formed at the four corners of the outer surfaces of the caps 17 and 19, and are curved in a direction along the inner peripheral surface 25 b of the caps 25. As shown in FIG. 7, hook-like edges 25 d and 25 d bent in the direction of the inner peripheral surface 25 b of the headboard 25 are formed on the pair of edge portions 25 c and 25 c of the headboard 25. The cap 25 is locked to the caps 17 and 19 by engaging the hooked edges 25d and 25d with the locking portions Ea and Ea of the caps 17 and 19. The saddle-shaped edges 25d and 25d of the headboard receivers 17 and 19 are formed in the lower part of the headboard headboard receivers 17 and 19, and extend in the longitudinal direction of the headboard receivers 17 and 19 with a certain distance from each other. In FIG. 7, reference numeral 26 indicates a blindfold tube. The blindfold tube 26 is fitted between the pair of edge portions 25c and 25c of the headboard receivers 17 and 19 as necessary, and seals the gap between the pair of edge portions 25c and 25c.

  The bridging portion 13 of the joint material 10 has an upper surface 14 and a lower surface 15, and has a plate shape as a whole so that bending deformation is possible only in the direction of the upper surface 14 and the direction of the lower surface 15. As shown in FIGS. 4 and 5, the bridging portion 13 is configured such that the axis line Xa of the first connecting end portion 11 and the axis line Ya of the second connecting end portion 12 are within a plane through which these axis lines Xa and Ya pass. It is smoothly curved so that it intersects at an angle of degrees. The angle of 140 degrees is an angle with many construction examples. The bridging portion 13 also connects the central portion of the first connecting end portion 11 and the central portion of the second connecting end portion 12.

  As shown in FIG. 3, the ribs 16 a and 16 b formed on the upper surface 14 and the lower surface 15 of the bridging portion 13 are formed on the right half of the bridging portion 13 toward the second connecting end portion 12. The ribs 16b and 16b are formed on the left half of the bridging portion 13 so as to alternate with the ribs 16a and 16a. These ribs 16a and 16b constitute plate-like ribs. The reason why the ribs 16a, 16a and the ribs 16b, 16b are formed alternately is that the gap Ga formed between the ribs 16a, 16a adjacent along the bridge portion 13 and the rib 16b adjacent along the bridge portion 13, This is because the comb-shaped half mold can be made to enter and exit from both sides of the bridging portion 13 by shifting the formation position of the gap Gb formed between 16b. As shown in FIG. 8, the ribs 16 a and 16 a have the same shape and dimensions, and the ribs 16 b and 16 b are symmetrical with respect to the central axis C. The ribs 16 a and 16 b are formed with a support surface Sb that contacts the inner peripheral surface 25 b of the headboard 25 and holds the shape of the headboard 25, and a locking portion Eb that locks the edge 25 c of the headboard 25. The support surface Sb is constituted by a convex curved surface. As shown in FIG. 8, the support surfaces Sb of the ribs 16 a and 16 a smoothly continue through the side surfaces of the bridging portion 13 so as to contact the inner peripheral surface 25 b of the headboard 25, and the support surfaces of the ribs 16 b and 16 b. Sb also continues smoothly through the side surface of the bridging portion 13. As shown in FIG. 6, when the joint material 10 is attached, the locking portions Eb of the ribs 16 a and 16 b are at positions corresponding to the locking portions Ea of the headboard receivers 17 and 19. Therefore, the hook-shaped edges 25d and 25d of the headboard 25 can be continuously locked to the locking portions Ea of the headboard receivers 17 and 19 and the locking portion Eb of the joint material 10.

  The gap Ga formed between the ribs 16a and 16a adjacent along the bridging portion 13 and the gap Gb formed between the ribs 16b and 16b adjacent along the bridging portion 13 include an upper surface of the bridging portion 13. 14 and the lower surface 15 are exposed. Thereby, the bridging portion 13 can be bent and deformed in the direction of the upper surface 14 and the direction of the lower surface 15. As shown in FIG. 9, in this embodiment, the angle Θ formed by the axis Xa of the first connecting end 11 of the joint member 10 and the axis Ya of the second connecting end 12 is set to 140 degrees, and the angle Θ Are set to ± 30 degrees that can be finely adjusted with reference to. By changing the areas of the upper surface 14 and the lower surface 15 of the bridging portion 13 exposed in the gaps Ga and Gb, the finely adjustable angles Θ1 and Θ2 can be set.

  As described above, the bridging portion 13 of the joint material 10 of the present embodiment connects the central portion of the first connecting end portion 11 and the central portion of the second connecting end portion 12, and the ribs 16a and 16a are connected to each other. Since the ribs 16b and 16b have the same shape and dimensions and the ribs 16a and 16a are symmetrical with respect to the central axis C, the corner shown in FIG. 2 can be obtained by inverting the joint material 10 as shown in FIG. Can be used to construct part 6. 10 and 11, reference numeral 25 indicates a headboard, reference numeral 27 indicates a headboard receiver for the handrail 8, reference numeral 28 indicates a headboard receiver for the handrail 9, reference numerals 18 and 20 indicate a set screw, and reference is made. Reference numerals 21 and 22 denote brackets for attaching the cap receivers 27 and 28 to the wall surface W. Further, in FIG. 10, reference numeral 27a indicates a cross-shaped hollow hole of the cap holder 27, reference numeral Sa indicates a support surface formed on the outer surface of the cap receivers 27 and 28, and reference numeral Ea indicates the cap rack. The latching | locking part of the receptacle 27 is shown. Reference numeral Ga indicates a gap formed between the adjacent ribs 16 a and 16 a along the bridging portion 13, and reference numeral Gb is formed between the adjacent ribs 16 b and 16 b along the bridging portion 13. The voids to be made are shown. Other configurations are the same as those of the joint material 10 shown in FIGS.

  12 to 16 show a second embodiment of the joint material of the present invention. In the following description, the same reference numbers as those used in FIGS. 1 to 11 indicate components of the reference numbers in FIGS. The feature of the joint material 100 is that the bridging portion 130 that connects the first connecting end portion 110 and the second connecting end portion 120 is formed along the lower surfaces 110a and 120a of the first and second connecting end portions 110 and 120. The pair of side wall ribs 160 and 170 are formed along both side edges of the bridging portion 130. These side wall ribs 160, 170 extend between the first and second connecting end portions 110, 120 and are opposed to each other with the bridging portion 130 interposed therebetween. The upper surface 140 of the bridging portion 130 is exposed between the side wall ribs 160 and 170, and the lower surface 150 of the bridging portion 130 is continuous with the lower surfaces 110 a and 120 a of the first and second connecting end portions 110 and 120. As shown in FIG. 16, a support surface Sb is formed on the outer surface of the side wall ribs 150, 160 so as to abut against the inner peripheral surface 25 b of the headboard 25 and maintain the shape of the headboard 25. , 170 and a convex curved surface continuous to the side surface of the bridging portion 130. In addition, locking portions Eb for locking the edge portion 25c of the headboard 25 are formed at both ends of the convex curved surfaces of the side wall ribs 160 and 170. The side wall ribs 160 and 170 include a plurality of grooves Gc extending from the edge of the side wall rib on the upper surface 140 side of the bridge portion 130 toward the upper surface 140 of the bridge portion 130, and the side wall on the lower surface 150 side of the bridge portion 130. A plurality of grooves Gd extending from the edge of the rib toward the lower surface 150 of the bridging portion 130 are formed. Other configurations and operations of the joint material 100 are the same as those in the first embodiment.

  The joint material 100 shown in FIGS. 12 to 16 can also be used by being inverted similarly to the joint material 10 of FIG. This is because the locking portion Eb for locking the edge portion 25c of the headboard 25 is formed at both edge portions of the convex curved surfaces of the side wall ribs 160 and 170 (see FIG. 16). However, since the joint member 100 according to the second embodiment of the present invention has the bridging member 130 formed along the lower surfaces 110a and 120a of the first and second connecting end portions 110 and 120, the upper surface 140 of the bridging member 130. The height of the side wall ribs 160, 170 on the side is larger than the height of the side wall ribs 160, 170 on the lower surface 150 side of the bridging member 130. For this reason, when the joint material 100 is inverted, the touch when the joint material 100 is gripped may change. Therefore, in the second example of the present invention, in addition to the embodiment of FIGS. 12 to 16, as shown in FIGS. 17 and 18, the joint material 100a in which the bridging portion 130a is curved in the direction opposite to the bridging portion 130 in advance is used. By preparing and using it as shown in FIG. 18, it is possible to make the feel when the joint material 100 is gripped constant. 17 and 18, the same reference numerals as those in FIGS. 1 to 16 denote the same components. 17 and 18 are the same as those of the joint material 100 shown in FIGS.

10, 100, 100a Joint material 11, 110 First connecting end portion 12, 120 Second connecting end portion 13, 130, 130a Bridge portion 14, 140 Upper surface 15, 150 Lower surface 16a, 16b Plate-like rib Ga, Gb Gap 160, 170 Side wall rib Gc, Gd Groove

Claims (5)

  A first connecting end connected to one handrail, a second connecting end connected to the other handrail, extending between the first and second connecting ends, and A bridging portion integrated with the first and second connecting end portions, the bridging portion having an upper surface and a lower surface, and capable of bending deformation only in the direction of the upper surface and the lower surface. In addition, the bridge portion has a plate-like form as a whole, and the bridging portion has an axis of the first connecting end and an axis of the second connecting end at a predetermined angle within a plane through which both the axes pass. Curved in advance in the direction of the upper surface or the lower surface so as to intersect, forming a rib integrally with the bridging portion, a support surface that contacts the inner surface of the headboard and holds the shape of the headboard on the rib, A handrail joint material characterized in that a locking portion for locking the edge of the headboard is formed.   2. The joint material according to claim 1, wherein the rib is configured by a plurality of plate-like ribs extending in a vertical direction from the upper surface and the lower surface and extending in a direction crossing the bridging portion, and the plate-like shape. A pair of plates in which ribs are arranged between the first and second connecting end portions at a predetermined interval and are adjacent to each other in the direction of the first and second connecting end portions of the plate-like ribs. A gap extending along the pair of plate-shaped ribs is formed between the ribs, and each of the gaps extends in a direction crossing the bridging portion and abuts against the inner surface of the headboard. A convex curved surface that retains the shape of the headboard is formed continuously with the side surface of the plate-like rib and the side surface of the bridging portion, and a locking portion that locks the edge of the headboard is formed on the convex curved surface. The joint material is formed at one or both end edges.   2. The joint material according to claim 1, wherein the rib extends between the first and second connecting end portions along both side edges of the bridging portion, and faces each other with the bridging portion interposed therebetween. A convex curved surface that is configured by a pair of side wall ribs and that extends in the vertical direction from the upper surface and the lower surface, and that holds the shape of the headboard by contacting the inner surface of the headboard, The side wall rib is formed continuously with the outer surface of the side wall and the side surface of the bridge portion, and a locking portion for locking the edge of the headboard is formed on one or both end edges of the convex curved surface, and the side wall The rib includes a plurality of grooves extending from the end edge portion of the side wall rib on the upper surface side toward the upper surface, and a plurality of grooves extending from the end edge portion of the side wall rib on the lower surface side toward the lower surface. The joint material is formed.   4. The joint material according to claim 1, wherein an axis of the first and second connecting end portions forms an angle of about 140 degrees, and the bridging portion has an angle of 140 degrees. 5. The joint material is capable of being bent and deformed in the direction of the upper surface and the lower surface within a range of ± about 30 degrees with respect to.   The joint material according to any one of claims 1 to 3, wherein the joint material is integrally formed of polypropylene resin.

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