COUPLING STRUCTURE FOR BEAMS WITH CLOSED CROSS-SECTION

Abstract

A coupling structure for joining closed-section beams is provided, comprising a pair of opposing through-holes. The coupling structure includes: a tube having an opening at one end located in one of the pair of through-holes and an opening at the other end located in the other of the pair of through-holes; a connector provided on the outside of each of the closed-section beams; a support adjacent to the connector; and bolts inserted into each of the closed-section beams through the second bolt holes, the first bolt holes, and the tube, and tightened with a nut. The tube is not attached to either the closed-section beams or the connector, and the diameter of the pair of through-holes is larger than the outside diameter of the tube.

Description

Technical area

[0001] The present disclosure relates to a coupling structure for a carrier with a closed cross-section. State of the art

[0002] For example, PTL 1 discloses a structure for attaching a suspension arm to a closed-section side member via a bracket. This bracket includes a tube that is inserted into the side member and into which a bolt is inserted, and a hanger to which one end of the tube is welded and which supports the suspension arm outside the side member. List of citationsPatent literature

[0003] PTL 1 Japanese Utility Model Application (Registration) Laid-Open No. 2-64408 Brief description of the inventionTechnical problem

[0004] Meanwhile, as methods for coupling longitudinal beams each having a closed cross-section, a method of joining longitudinal beams by welding and a method of welding a nut to the inside of a closed cross-section and fastening a bolt to the nut from the outside of the cross-section are known in the prior art. However, these methods have problems in terms of cost and strength.

[0005] Therefore, the bracket described above is intended to couple longitudinal members with a closed cross-section. However, in this case, problems may arise, including a deepening of the support surface and a reduction in the axial force of a bolt.

[0006] An object of one aspect of the present disclosure is to provide a coupling structure for a closed-section beam capable of preventing a depression of the support surface and a reduction in the axial force of a bolt. Solution to the problem

[0007] A coupling structure according to one aspect of the present disclosure is a coupling structure for a closed-section beam, the coupling structure coupling a first closed-section beam and a second closed-section beam, the first closed-section beam and the second closed-section beam each having a pair of through-holes opposite each other with a gap between the pair of through-holes, the coupling structure including: tubes each having an opening part at one end thereof and another opening part at another end thereof,wherein the opening part is arranged at one end at one of the two through-holes and the other opening part is arranged at the other end at another of the two through-holes in an inner part of the corresponding first closed-section beam or the second closed-section beam; a connecting piece having a first bolt hole having a smaller diameter than the outer diameter of each of the tubes, the connecting piece being provided at the respective outer parts of the first closed-section beam and the second closed-section beam, such that the first bolt hole communicates with the pair of through-holes; a bracket having a plurality of second bolt holes, the bracket coming into contact with the connecting piece, such that each of the plurality of second bolt holes communicates with the first bolt hole of the connecting piece,provided on the respective end faces of the first closed-section beam and the second closed-section beam, the respective end faces being present on a same side; and bolts each inserted into a corresponding one of the second bolt holes, the first bolt hole, and a corresponding one of the tubes in a corresponding one of the first closed-section beam and the second closed-section beam, and each fastened with a nut, the tubes not being fastened to any of the first closed-section beam, the second closed-section beam, and the connecting piece, and a diameter of each of the two through holes being larger than the outer diameter of each of the tubes. Advantageous effects of the invention

[0008] According to the present disclosure, it is possible to prevent a depression of the bearing surface and a reduction of the axial force of a bolt. Short description of the drawings Fig. 1 is a perspective view in which a side member, tubes, and a connector are disassembled from each other according to an embodiment of the present disclosure; Fig. 2 is a perspective view of the longitudinal member to which the tubes and the connector are attached according to an embodiment of the present disclosure; Fig. 3 is a perspective view of a coupling structure according to an embodiment of the present disclosure; Fig. 4 is a schematic sectional view of the coupling structure according to an embodiment of the present disclosure; and Fig. 5 is a schematic sectional view of a coupling structure according to a comparative example of the present disclosure. Description of the embodiments

[0009] An embodiment of the present disclosure will be described below with reference to the drawings. Components that appear multiple times in the drawings are denoted by the same symbols, and descriptions of these components will be omitted where appropriate.

[0010] First, with reference to Fig. 1 and Fig. 2 of the longitudinal beam 1, the tubes 3 and the connecting piece 4 in the present embodiment are described. Fig. 3 and Fig. 4 may also be referred to.

[0011] Fig. 1 is a perspective view in which the longitudinal members 1, tubes 3 and connecting piece 4 are disassembled from each other. Fig. Figure 2 is a perspective view of the longitudinal member 1, to which the tubes 3 and the connecting piece 4, which are shown in Fig. 1 are attached.

[0012] The longitudinal member 1 (an example of a first closed-section beam) is a beam having a closed-section structure and is, for example, a vehicle body frame to be mounted on a large commercial vehicle.

[0013] The longitudinal member 1 has an end face A and an end face B, which are opposite each other with a gap. Each of the end faces A and B has a plurality of through holes 2 in the longitudinal direction of the longitudinal member 1.

[0014] The through holes 2 on the end face A and the through holes 2 on the end face B are provided so that they are opposite one another one to one. This means that the longitudinal member 1 can be said to have a plurality of pairs of through holes 2 in the longitudinal direction of the longitudinal member 1.

[0015] The diameter of each through hole 2 is larger than the outer diameter of each tube 3.

[0016] Each tube 3 is a cylindrical steel tube through which a hole extends in the axial direction and has opening parts (without indication of symbols) at its two ends.

[0017] A plurality of tubes 3 are provided, the number of which corresponds to the number of pairs of through-holes 2. Each tube 3 is inserted into the longitudinal member 1 (into the closed cross-section) through a corresponding one of the through-holes 2 on the end face A or on the end face B. At this time, the opening part at one end is arranged at the corresponding through-hole 2 on the end face A, and the other opening part at the other end is arranged at the corresponding through-hole 2 on the end face B (see Fig. 4).

[0018] The tubes 3 are neither attached to the longitudinal member 1 nor to the connecting piece 4 and are arranged inside the longitudinal member 1 (see Fig. 4).

[0019] The Fig. 3 and Fig. The bolts 10 shown in Figure 4 are inserted into the corresponding tubes 3. Since the tubes 3 act as deformation inhibitors, it is possible to prevent loss of the axial force of the bolts 10 and to ensure a required fastening force.

[0020] The connecting piece 4 is a plate-shaped long part. The connecting piece 4 has a plurality of bolt holes 5 (an example of a first bolt hole), the number of which corresponds to the number of through holes 2 (pipes 3).

[0021] The diameter of each bolt hole 5 is smaller than the outer diameter of each pipe 3. In an example of the present embodiment, the diameter of each bolt hole 5 is the same as the inner diameter of each pipe 3 (see Fig. 4).

[0022] As in Fig. 2, the connecting piece 4 is fastened to the end face A of the longitudinal member 1 via the weldment 6. Specifically, the connecting piece 4 is aligned so that each bolt hole 5 is connected to one of the corresponding through holes 2 on the end face A, and the connecting piece 4 is welded to the end face A (see Fig. 4). Although in Fig. 2 not shown, the connecting piece 4 on the front side B is provided similar to the one above (see Fig. 4).

[0023] Since the connecting piece 4 is therefore fixed to both the end face A and the end face B, it is possible to prevent each pipe 3 arranged inside the longitudinal member 1 from protruding from the longitudinal member 1.

[0024] Next, the coupling structure 100 (an example of a coupling structure for a closed-section beam) in the present embodiment, which has the structure shown in Fig. 2, with reference to Fig. 3 and Fig. 4 described.

[0025] Fig. 3 is a perspective view of the coupling structure 100. Fig. 4 is a schematic sectional view of the coupling structure 100.

[0026] The coupling structure 100 is a structure in which the side member 1 and the side member 7 (an example of a second closed-section beam) arranged below the side member 1 are coupled to each other using brackets 8, bolts 10, and nuts 11.

[0027] The longitudinal member 7 has the same structure as the longitudinal member 1 described above. Therefore, a description thereof is omitted here.

[0028] The brackets 8 are each a plate-shaped part which is to be used for the coupling between the longitudinal member 1 and the longitudinal member 7.

[0029] Each bracket 8 has a plurality of bolt holes 9 (an example of a second bolt hole), the number of which corresponds to the number of through holes 2 (tubes 3) provided in the side members 1 and 7.

[0030] In an example of the present embodiment, the diameter of each bolt hole 9 is the same as the diameter (the inner diameter of each pipe 3) of each bolt hole 5 of the joint 4 (see Fig. 4).

[0031] As in Fig. 3, the bracket 8 is provided on the respective end face A of the side members 1 and 7. Specifically, the bracket 8 is oriented such that each bolt hole 9 communicates with a corresponding one of the bolt holes 5 (a corresponding one of the through holes 2 on the end face A) of the connecting piece 4 provided on the respective end faces A of the side members 1 and 7, and the bracket 8 comes into contact with the connecting piece 4 on the respective end faces A of the side members 1 and 7 (see Fig. 4). Although in Fig. 3, the bracket 8 is also provided on the respective end faces B of the longitudinal beams 1 and 7, similar to the above (see Fig. 4).

[0032] As in Fig. 4, each bolt 10 in a corresponding one of the longitudinal members 1 and 7 is inserted into the bolt hole 9 of the bracket 8 on the end face B, the bolt hole 5 of the connecting piece 4 on the end face B, the tube 3, the bolt hole 5 of the connecting piece 4 on the end face A and the bolt hole 9 of the bracket 8 on the end face A. As shown in Fig. 3 and Fig. 4, the nut 11 is then fastened to the bolt 10 at the respective end faces A of the longitudinal members 1 and 7.

[0033] Because the bolts 10 are each fastened with the nut, the longitudinal member 1 and the longitudinal member 7 are coupled to each other via the brackets 8.

[0034] Here, the coupling structure 200 is described as a comparative example of the present disclosure with reference to Fig. 5 described. Fig. 5 is a schematic sectional view of the coupling structure 200.

[0035] In Fig. 5 are the same components as in Fig. 1 to Fig. 4 are marked with the same symbols. Therefore, the description of these components is omitted in the following description. In Fig. 5 shows a fastening point of bolt 10 and nut 11 in each of the longitudinal members 1 and 7. In fact, however, there are a plurality of fastening points in the longitudinal direction of the longitudinal members 1 and 7, similar to the coupling structure 100 described above.

[0036] The coupling structure 200 differs from the coupling structure 100 described above (see Fig. 4) in that one end (an end part on the front side A) of each pipe 3 is fixed to the connecting piece 4 by a weldment 6.

[0037] Taking into account additional variations of the weldments 6 between the tubes 3 and the connector 4, such a coupling structure 200 requires an enlargement of the diameter of each through-hole 2 provided on the respective end faces B of the longitudinal members 1 and 7 and the diameter of each bolt hole 9 provided in the bracket 8 on the end face B, so that the bolts 10 can extend through the holes at all attachment points.

[0038] When the diameter of each through hole 2 provided at the respective end faces B of the longitudinal beams 1 and 7 is increased, the contact between the other end (the end part at the end face B) of each tube 3 and a corresponding one of the longitudinal beams 1 and 7 at the end face B is lost (in other words, the area in which the other end of each tube 3 comes into contact with the corresponding one of the longitudinal beams 1 and 7 decreases), as shown in Fig. 5. Therefore, there is a likelihood that the axial force of the bolts 10 will decrease.

[0039] As the diameter of each bolt hole 9 provided on the end face B of the bracket 8 is increased, the area where the bracket 8 contacts the seating surface of the head portion of each bolt 10 decreases. Therefore, there is a possibility that the seating surface of the head portion of each bolt 10 may be deepened.

[0040] The more attachment points there are, the greater the likelihood that this is a critical point, especially in a structure that requires strength and rigidity against a large load. Such a structure is, for example, the body frame of a commercial vehicle or the like.

[0041] In contrast, in the coupling structure 100 in the present embodiment, the through holes 2 in the longitudinal beams 1 and 7 have a diameter larger than the outer diameter of each pipe 3, and the pipes 3 are not fixed to the longitudinal beams 1 or 7 or the connecting piece 4 and are enclosed by the closed cross section of the longitudinal beams 1 or 7. Therefore, the pipes 3 are movable in one direction (the directions are indicated by arrows a and b in Fig. 4), which runs perpendicular to the axial direction of the tubes 3.

[0042] Consequently, the insertion of the bolts 10 is not hindered by the positions of the tubes 3. Therefore, compared to the coupling structure 200, the diameter of each through hole 2 in each of the side members 1 and 7 and the diameter of each bolt hole 9 in the brackets 8 can be reduced, and the recession of the support surface and the reduction of the axial force of the bolts 10 described above can be prevented.

[0043] It should be noted that the present disclosure is not limited by the description of the above-mentioned embodiment and can be modified in various ways within a scope that does not deviate from the gist of the present disclosure.

[0044] This application is based on Japanese patent application (Japanese Patent Application No. 2021-203295) filed on December 15, 2021, the contents of which are incorporated herein by reference. Industrial applicability

[0045] The coupling structure for a closed-section beam according to the present disclosure is useful as a structure that couples two closed-section beams together. List of reference symbols 1, 7 longitudinal members 2 through holes 3 pipe 4 connecting piece 5, 9 bolt hole 6 Welded part 8 Bracket 10 bolts 11 Mother 100, 200 Coupling structure for beams with closed cross-section QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2-64408

[0003] JP 2021-203295

[0044]

Claims

[1] A coupling structure for a closed-section carrier, the coupling structure coupling a first closed-section carrier and a second closed-section carrier, the first closed-section carrier and the second closed-section carrier each having a pair of through-holes opposite each other with a gap between the pair of through-holes, the coupling structure comprising: Tubes each having an opening part at one end thereof and another opening part at another end thereof, wherein the opening part at one end is arranged at one of the two through holes and the other opening part at the other end is arranged at another of the two through holes in an inner part of the corresponding first closed-section beam or the second closed-section beam; a connector having a first bolt hole whose diameter is smaller than the outer diameter of each of the tubes, the connector being provided on the respective outer parts of the first closed-section beam and the second closed-section beam so that the first bolt hole communicates with the pair of through holes; a bracket having a plurality of second bolt holes, the bracket contacting the connecting piece such that each of the plurality of second bolt holes communicates with the first bolt hole of the connecting piece provided on the respective end faces of the first closed-section beam and the second closed-section beam, the respective end faces being provided on a same side; and Bolts each inserted into a corresponding one of the second bolt holes, the first bolt hole and a corresponding one of the tubes in a corresponding one of the first closed-section beam and the second closed-section beam and each fastened with a nut, wherein the tubes are not attached to any of the first closed-section support, the second closed-section support and the connecting piece, and wherein a diameter of each of the two through holes is larger than the outer diameter of each of the tubes. [2] A coupling structure for a closed-section beam according to claim 1, wherein the first closed-section beam and the second closed-section beam are each a longitudinal beam to be mounted on a vehicle. [3] The coupling structure for a closed-section beam according to claim 1, wherein the first closed-section beam is provided above the second closed-section beam.

Images