Fixing structure of pipe nut

Abstract

To provide a fixing structure of a pipe nut which can secure attachment rigidity of a pipe nut to a vehicle body frame and enables improvement of assemblability and improvement of rigidity of the vehicle body frame.SOLUTION: A fixing structure of a pipe nut 14 is a structure which fixes a pipe nut main part 14a to a front side frame 6 having a hollow cross section 15 and includes: a lower insertion hole 12e which is provided at the front side frame 6 and in which the pipe nut main part 14a is inserted in a state of being able to rotate around a center axis O; a slit 12f extending from the lower insertion hole 12e; a joint flange part 14b which is provided at a base end of the pipe nut main part 14a and contacts with an outer surface of the front side frame 6 to restrict movement of the pipe nut main part 14a in a longitudinal direction; and a reinforcement plate 14c which extends from a side surface of the pipe nut main part 14a, passes through the slit 12f, and is disposed in the front side frame 6. The reinforcement plate 14c is joined to an inner surface of the front side frame 6 at a rotated position.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a fixing structure for pipe nuts provided on a vehicle body frame for bolt fastening a subframe to the vehicle body frame. [Background technology]

[0002] Conventionally, front side frames extending in the longitudinal direction are disposed on both sides of the front of a vehicle body of an automobile, etc. Below the front side frames, subframes such as suspension cross members that support the suspension and the like extend in the vehicle width direction.

[0003] Both ends of such a suspension cross member are generally attached to the front side frames by bolts, and pipe nuts with internal threads are attached to the front side frames to fasten both ends of the suspension cross member to the front side frames.

[0004] Various techniques have been proposed as fixing structures for increasing the mounting rigidity of pipe nuts.

[0005] For example, Patent Document 1 (JP 2011-230602 A) discloses a structure in which a pipe nut is provided with a reinforcing member to prevent it from tilting, and the reinforcing member is joined to the inner surface of the body frame to fix the pipe nut. Such a reinforcing member not only increases the mounting rigidity of the pipe nut, but also increases the rigidity of the body frame.

[0006] In the case of such a fixing structure, it is common to weld the reinforcing member to the inner surface of the vehicle body frame in a state where the pipe nut and the reinforcing member are sub-assembled.

[0007] In order to further improve the mounting rigidity of such a fixing structure in which the fixing member is only welded from the inside of the body frame, it is preferable to also weld the fixing member from the outside of the body frame.

[0008] One possible fixing structure for improving the mounting rigidity of such a pipe nut is one in which a flange portion is provided at the lower end of the pipe nut, which is welded in contact with the outer surface of the vehicle body frame. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-230602 Summary of the Invention [Problem to be solved by the invention]

[0010] However, with such a fixing structure, it may be difficult to sub-assemble the pipe nut and the reinforcing member, which may deteriorate the ease of assembly.

[0011] The present invention has been made in consideration of the above circumstances, and has an object to provide a pipe nut fixing structure that ensures the mounting rigidity of the pipe nut to the body frame, improves assembly ease, and further increases the rigidity of the body frame. [Means for solving the problem]

[0012] The present invention provides a pipe nut fixing structure for fixing a pipe nut body to a body frame having a hollow cross section, the structure comprising: an insertion hole provided in the body frame, through which the pipe nut body is inserted so as to be rotatable around the central axis of the pipe nut body; a slit provided in the body frame and extending from the insertion hole; a first stopper provided at the base end of the pipe nut body, which abuts against the outer surface of the body frame to restrict longitudinal movement of the pipe nut body; and a second stopper extending from the side of the pipe nut body, passing through the slit and positioned inside the body frame, the second stopper being joined to the inner surface of the body frame at a position rotated around the central axis from the slit. [Effects of the Invention]

[0013] The pipe nut fixing structure of the present invention ensures the mounting rigidity of the pipe nut to the vehicle body frame, improves assembly efficiency, and further increases the rigidity of the vehicle body frame. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is an exploded perspective view of a body frame and a suspension cross member according to a first embodiment. [Figure 2] FIG. 1 is an enlarged perspective view of a main portion of a body frame according to a first embodiment; [Figure 3] FIG. 1 is an exploded perspective view showing an enlarged view of a main part of a body frame according to a first embodiment; [Figure 4] IV-IV cross-sectional view of FIG. 2 according to the first embodiment. [Figure 5] 1 is a perspective view of a pipe nut according to a first embodiment, viewed obliquely from below; [Figure 6] 6 is a cross-sectional view taken along line VI-VI of FIG. 4 according to the first embodiment; [Figure 7] 4 according to the second embodiment. [Figure 8] FIG. 10 is an enlarged exploded perspective view of a main portion of a body frame according to a third embodiment. [Figure 9]FIG. 10 is a perspective view of an inner frame according to a third embodiment, viewed obliquely from below; DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0016] In the drawings used in the following description, different scales are used for each component so that each component can be recognized on the drawing. Therefore, the present invention is not limited to the number of components, the shapes of components, the size ratios of components, and the relative positional relationships of each component shown in these drawings. Furthermore, in the following description, when the term "joining" is used, it is assumed that the joining method is performed using a joining means such as fusion joining or mechanical joining. In the drawings, only spot welds are marked with spot welding symbols, and other welds are not marked with welding symbols. [First embodiment]

[0017] As shown in FIG. 1, an engine room 2 is provided in the front part of a vehicle body 1.

[0018] The engine room 2 is separated from the rear cabin 3 by a toeboard 4.

[0019] The vehicle body 1 has frames that make up the engine compartment 2, including a pair of left and right front side frames 6, a pair of left and right upper side frames 7, and a suspension cross member 9. These frames are formed, for example, by pressing sheet metal members made of high-strength steel plate or the like.

[0020] The basic structure around the pair of left and right front side frames 6 and the pair of left and right upper side frames 7 is symmetrical. Therefore, the left side of the vehicle body will be described below as an example.

[0021] As shown in FIG. 1, the front side frames 6 extend from the lower part of the toe board 4 toward the front of the vehicle body 1 on the outer sides of the toe board 4 in the vehicle width direction.

[0022] The upper side frames 7 are provided above the front side frames 6 and further outward in the vehicle width direction than the front side frames 6. The upper side frames 7 extend along the engine compartment 2 toward the front of the vehicle body.

[0023] A suspension tower 8 is provided between the front side frame 6 and the upper side frame 7 near the rear of the engine room 2 .

[0024] The suspension tower 8 accommodates a suspension device (not shown) therein and supports the upper part of the suspension device.

[0025] Furthermore, a wheel apron 5 is provided between the front side frame 6 and the upper side frame 7, in front of the suspension tower 8.

[0026] The suspension cross member 9 is disposed as a subframe below the front side frame 6. That is, the suspension cross member 9 extends in the vehicle width direction below the front side frame 6. The suspension cross member 9 has a shape in which the center portion curves downward.

[0027] The ends of such suspension cross members 9 in the vehicle width direction are joined to the bottom surfaces of the front side frames 6 by bolting.

[0028] In order to fasten such a suspension cross member 9 with bolts, a pair of pipe nuts 14 are provided on the front and rear of the front side frame 6, which serves as the body frame.

[0029] The configuration of the front side frame 6 and the suspension cross member 9 will be described in detail below.

[0030] 1 and 2, the front side frame 6 has an inner frame 12 and an outer frame 13. Note that in FIG. 1, a portion of the outer frame 13 of the left front side frame 6 is omitted.

[0031] 2 to 4, the inner frame 12 has a generally hat-shaped cross section that protrudes inward in the vehicle width direction. The inner frame 12 has an inner wall portion 12a, an upper wall portion 12b, a lower wall portion 12c, and a pair of upper and lower inner flanges 12d.

[0032] The inner wall portion 12a extends in the vertical direction of the vehicle body.

[0033] The upper wall portion 12b and the lower wall portion 12c extend outward in the vehicle width direction from both ends of the inner wall portion 12a.

[0034] A pair of upper and lower inner flanges 12d protrude in the vertical direction of the vehicle body from the outer surface of the inner frame 12. Specifically, they extend in the vertical direction of the vehicle body from the outer edges of the upper wall portion 12b and the lower wall portion 12c in the vehicle width direction. Each of these inner flanges 12d functions as a flange for joining the inner frame 12 to the outer frame 13. In addition, the inner flanges 12d extending from the lower wall portion 12c also function as abutment portions for a pair of rotation restriction portions 14h, which will be described later.

[0035] 2 to 4, the outer frame 13 is disposed at a position facing the outer side of the inner frame 12 in the vehicle width direction. The outer frame 13 is a flat plate that closes the opening of the inner frame 12.

[0036] For this reason, the outer frame 13 has a pair of upper and lower outer flanges 13a at positions facing each of the inner flanges 12d.

[0037] The outer frame 13 is joined with each outer flange 13a abutting against each inner flange 12d.

[0038] As a result, the front side frame 6 has a generally rectangular cross section with a hollow cross section 15, as shown in FIG.

[0039] A pair of front and rear pipe nuts 14 can be inserted into the lower wall portion 12c of such a front side frame 6. For this reason, the lower wall portion 12c is provided with insertion holes for inserting each pipe nut 14 therethrough.

[0040] 3, the lower wall portion 12c is provided with a pair of front and rear lower insertion holes 12e. Furthermore, the lower wall portion 12c is provided with a pair of front and rear slits 12f extending from each lower insertion hole 12e in the longitudinal direction of the vehicle body. Each slit 12f is provided for inserting a pair of reinforcing plates 14c (described later) therethrough.

[0041] As shown in FIG. 5, the pipe nut 14 inserted into each set of lower insertion holes 12e and each set of slits 12f has a pipe nut body 14a, a joining flange portion 14b, and a pair of reinforcing plates 14c.

[0042] As shown in Figures 4 and 6, the pipe nut body 14a has, for example, a generally cylindrical shape with one end closed. A hole formed in this pipe nut body 14a is set as a bolt insertion hole 14e. Furthermore, a female thread portion 14f is formed on the inner surface of the bolt insertion hole 14e. Note that a bolt 19 (described later) can be threaded into the female thread portion 14f. The outer diameter of this pipe nut body 14a is set slightly smaller than the inner diameter of the lower insertion hole 12e. This allows the pipe nut body 14a to be inserted into the lower insertion hole 12e. Furthermore, the pipe nut body 14a inserted into the lower insertion hole 12e is rotatable around the central axis O of the pipe nut body 14a.

[0043] The joining flange portion 14b is provided at the base end of the pipe nut body 14a. As shown in Fig. 5, the basic shape of the joining flange portion 14b is, for example, a rectangular flat plate. The joining flange portion 14b extends in a direction perpendicular to the central axis O of the pipe nut body 14a. That is, when the joining flange portion 14b abuts against the outer surface of the bottom wall portion 12c, it functions as a first stopper that restricts longitudinal movement of the pipe nut body 14a.

[0044] Furthermore, the extended portions of the joining flange portion 14b function as welds to the lower wall portion 12c. That is, the four corners of the joining flange portion 14b can be spot-welded while the joining flange portion 14b is in contact with the outer surface of the lower wall portion 12c.

[0045] In the following description, for convenience, a direction perpendicular to the central axis O and in which the long side of the joining flange portion 14b extends is defined as a first direction D1 as shown in Fig. 5. A direction perpendicular to the central axis O and perpendicular to the first direction D1 is defined as a second direction D2.

[0046] The joining flange portion 14b is provided with rotation restricting portions 14h that protrude in the second direction D2 from a pair of long sides. The amount of protrusion of each rotation restricting portion 14h in the second direction D2 is determined based on the distance from the lower insertion hole 12e of the front side frame 6 to the inner flange 12d. Specifically, as shown in FIG. 3, when the pipe nut body 14a is inserted into the lower insertion hole 12e and the joining flange portion 14b is positioned so that the first direction D1 coincides with the longitudinal direction of the front side frame 6, one of the pair of rotation restricting portions 14h is configured to abut against the inner flange 12d. This allows each rotation restricting portion 14h to restrict rotation of the pipe nut body 14a inserted into the lower insertion hole 12e.

[0047] As shown in FIG. 5, a boss portion 14d that protrudes downward is formed at the lower end of the joining flange portion 14b.

[0048] The boss portion 14d is formed in an annular shape, and a bearing surface 14g is provided on the protruding surface of the boss portion 14d.

[0049] 4 and 6, the upper surface of the suspension cross member 9 can come into contact with the seating surface 14g. In other words, the seating surface 14g functions as a mounting surface when bolting the suspension cross member 9. For this reason, the seating surface 14g is substantially flat.

[0050] As shown in Fig. 5, the pair of reinforcing plates 14c are each formed, for example, by a flat plate having a generally rectangular shape in front view. Each reinforcing plate 14c is provided on a side surface of the pipe nut body 14a. These reinforcing plates 14c are provided at positions rotationally symmetrical with respect to the central axis O of the pipe nut body 14a. Furthermore, on the side surface of the pipe nut body 14a, each reinforcing plate 14c is arranged so that the plate surface extends in the direction of the central axis O and the second direction D2.

[0051] The height H1 of each reinforcing plate 14c is set to be substantially the same as the height H2 in the internal space of the front side frame 6 in the direction of the central axis O of the pipe nut body 14a (see FIGS. 4 and 5).

[0052] In addition, in the second direction D2, the width dimension W1 from the extending end of one reinforcing plate 14c to the extending end of the other reinforcing plate 14c is set to be approximately the same as the width dimension W2 in the vehicle width direction in the internal space of the front side frame 6 (see Figures 4 and 5).

[0053] Here, a gap wider than at least the thickness of the lower wall portion 12c is provided between the base end of each reinforcing plate 14c and the joining flange portion 14b. The dimension of each slit 12f through which each reinforcing plate 14c is inserted in the vehicle front-rear direction is set slightly larger than the dimension of each reinforcing plate 14c in the second direction D2. Furthermore, the dimension of each slit 12f through which each reinforcing plate 14c is inserted in the vehicle width direction is set slightly larger than the thickness of each reinforcing plate 14c.

[0054] As a result, each reinforcing plate 14c can be inserted into each slit 12f. Furthermore, each reinforcing plate 14c inserted into each slit 12f is disposed inside the front side frame 6 and is rotatable around the central axis O of the pipe nut body 14a.

[0055] Next, a description will be given of the procedure for assembling such pipe nuts 14 to the front side frames 6. The pipe nuts 14 are assembled to the inner frame 12 before the outer frame 13 is welded thereto.

[0056] First, as shown in Fig. 3, an assembly worker (hereinafter referred to as a worker) aligns the pipe nut 14 below the inner frame 12 so that the central axis O of the pipe nut body 14a coincides with the center of the lower insertion hole 12e. At this time, the worker adjusts the first direction D1 of the pipe nut 14 so that it coincides with the vehicle width direction of the inner frame 12.

[0057] As a result, each reinforcing plate 14c is aligned with a position where it can be inserted into each slit 12f.

[0058] In this state, the worker inserts the pipe nut body 14a and the reinforcing plates 14c into the lower insertion hole 12e and the slits 12f.

[0059] Then, when the connecting flange portion 14b abuts against the outer surface of the lower wall portion 12c, the worker rotates the connecting flange portion 14b. The rotation of the connecting flange portion 14b continues until one of the rotation restricting portions 14h abuts against the inner flange 12d. That is, the inner flange 12d restricts the rotation of the pipe nut 14 by abutting against the rotation restricting portion 14h. In this way, the inner flange 12d functions as a first protrusion for restricting the rotation of the pipe nut 14.

[0060] As a result, the first direction D1 of the pipe nut 14 coincides with the vehicle body fore-and-aft direction of the inner frame 12. In other words, when the rotation restricting portion 14h abuts against the inner flange 12d, each reinforcing plate 14c extends in a direction perpendicular to the longitudinal direction of the inner frame 12.

[0061] At this time, the base end edge of each reinforcing plate 14c abuts against the inner surface of the lower wall portion 12c, thereby preventing the pipe nut 14 from falling off the inner frame 12.

[0062] Furthermore, the edge of one reinforcing plate 14c abuts against the inner surfaces of the inner wall 12a and the upper wall 12b, and the edge of the other reinforcing plate 14c abuts against the inner surface of the upper wall 12b.

[0063] In this state, the worker joins each reinforcing plate 14c to the inner surfaces of the inner wall portion 12a and the upper wall portion 12b by arc welding. Furthermore, the worker joins the joining flange portion 14b to the outer surface of the lower wall portion 12c by spot welding. In this way, the pipe nut 14 is assembled to the inner frame 12.

[0064] Then, the worker joins the inner flanges 12d of the inner frame 12 to the outer flanges 13a of the outer frame 13 in abutting relation to each other.

[0065] It is also possible to perform some or all of the above assembly work using a machine tool instead of a worker.

[0066] 2, 4, and 6, the pipe nut body 14a assembled inside the front side frame 6 is supported by the reinforcing plates 14c and joined to the inner surface of the front side frame 6 via the reinforcing plates 14c. This allows the reinforcing plates 14c to restrict movement of the pipe nut body 14a in the prying direction (the direction tilting relative to the central axis) and in the longitudinal direction. Thus, in this embodiment, the reinforcing plates 14c correspond to a specific example of a second stopper.

[0067] Furthermore, each reinforcing plate 14c extends inside the front side frame 6 in a direction perpendicular to the longitudinal direction of the front side frame 6. Each reinforcing plate 14c also functions as a reinforcing member that reinforces the front side frame 6 inside the front side frame 6.

[0068] As shown in FIGS. 1, 4, and 6, the suspension cross member 9 has an upper panel 40, a lower panel 41, and a reinforcement 42.

[0069] The upper panel 40 has an open cross-sectional shape that opens downward toward the vehicle body, for example. As shown in Fig. 4, the upper panel 40 has an attachment portion 40a and a side wall portion 40b.

[0070] The mounting portion 40a is disposed at a position facing the lower wall portion 12c. The mounting portion 40a abuts against the bearing surface 14g of the pipe nut 14 and functions as a mounting portion when fixing the suspension cross member 9 to the front side frame 6.

[0071] For this reason, the mounting portion 40a has a pair of first bolt insertion holes 40c at the front and rear.

[0072] The pair of front and rear first bolt insertion holes 40c are provided at positions facing the respective bolt insertion holes 14e. That is, each first bolt insertion hole 40c and each bolt insertion hole 14e are arranged substantially coaxially.

[0073] The side wall portion 40b extends downward from the outer edge portion of the mounting portion 40a in the vehicle width direction.

[0074] The lower panel 41 is disposed opposite the upper panel 40 with a space therebetween. Second bolt insertion holes 41a are formed in the lower panel 41 at positions opposite each of the first bolt insertion holes 40c. That is, each of the second bolt insertion holes 41a and each of the first bolt insertion holes 40c are disposed substantially coaxially.

[0075] The outer edge portion in the vehicle width direction of the lower panel 41 is bent downward. The lower end portion of the side wall portion 40b of the upper panel 40 is joined to the outer surface in the vehicle width direction of the bent lower panel 41.

[0076] By joining the upper panel 40 and the lower panel 41 in this manner, an internal space is formed in the suspension cross member 9.

[0077] The reinforcement 42 is disposed inside the suspension cross member 9. Specifically, the reinforcement 42 extends along the upper panel 40 in the vehicle width direction.

[0078] The outer end of the reinforcement 42 in the vehicle width direction is in contact with the inner surface of the mounting portion 40a, as shown in Fig. 4. The outer end of the reinforcement 42 in the vehicle width direction is joined to the mounting portion 40a.

[0079] Furthermore, third bolt insertion holes 42a are provided at positions facing the first bolt insertion holes 40c at the joints of the reinforcement 42. That is, the third bolt insertion holes 42a and the first and second bolt insertion holes 40c, 41a are arranged substantially coaxially.

[0080] As shown in FIGS. 4 and 6, a pair of front and rear spacers 43 extend between the reinforcement 42 and the lower panel 41.

[0081] The pair of front and rear spacers 43 are generally cylindrical. A hole formed in each spacer 43 is set as a fourth bolt insertion hole 43a that penetrates in the vertical direction of the vehicle body. That is, the fourth bolt insertion hole 43a of each spacer 43 is disposed generally coaxially with the first to third bolt insertion holes 40c, 41a, 42a.

[0082] The bolts 19 can be inserted into the first to fourth bolt insertion holes 40c, 41a, 42a, and 43a arranged in this manner.

[0083] In the following description, the first to fourth bolt insertion holes 40c, 41a, 42a, and 43a will be collectively referred to as bolt insertion holes H.

[0084] With this configuration, the suspension cross member 9 is fixed to the front side frame 6 by fastening bolts.

[0085] More specifically, when the suspension cross member 9 is fixed to the front side frame 6, the mounting portion 40a abuts against each of the seat surfaces 14g from below.

[0086] Furthermore, each bolt insertion hole H is positioned relative to the bolt insertion hole 14e of each pipe nut 14.

[0087] A bolt 19 is inserted into each positioned pair of bolt insertion hole H and bolt insertion hole 14e from below the bolt insertion hole H. Each bolt 19 is then threaded into the female thread portion 14f of the pipe nut 14. In this way, the suspension cross member 9 is fastened to the front side frame 6.

[0088] An arm support portion 45 is provided on the outer side in the vehicle width direction of the suspension cross member 9 fixed in this manner.

[0089] 1, arm support portion 45 protrudes downward from the bottom surface of lower panel 41 on the outer side in the vehicle width direction. A base end portion of suspension lower arm 50 is journaled on arm support portion 45. This allows the tip end side of suspension lower arm 50 to swing freely in the up and down direction.

[0090] The lower part of a suspension device (not shown) is supported on the outer side in the vehicle width direction of this suspension lower arm 50. Furthermore, a wheel hub (not shown) to which a front wheel is fixed is rotatably supported on the outer side in the vehicle width direction of the suspension lower arm 50.

[0091] According to this embodiment, the fixing structure of the pipe nut 14 is a fixing structure of the pipe nut 14 that fixes the pipe nut body 14a to the front side frame 6 having a hollow cross section 15, and includes: a lower insertion hole 12e that is provided in the front side frame 6 and through which the pipe nut body 14a is inserted so as to be rotatable around the central axis O of the pipe nut body 14a; a slit 12f that is provided in the front side frame 6 and extends from the lower insertion hole 12e; a joining flange portion 14b that is provided at the base end of the pipe nut body 14a and abuts against the outer surface of the front side frame 6 to restrict longitudinal movement of the pipe nut body 14a; and a reinforcing plate 14c that extends from the side of the pipe nut body 14a, passes through the slit 12f, and is positioned inside the front side frame 6, and the reinforcing plate 14c is joined to the inner surface of the front side frame 6 at a position rotated around the central axis O from the slit 12f. With these configurations, the fixing structure of the pipe nut 14 ensures the mounting rigidity of the pipe nut 14 to the body frame, improves assembly efficiency, and further increases the rigidity of the body frame.

[0092] That is, in this embodiment, a pair of reinforcing plates 14c disposed inside the front side frame 6 extend from the side surfaces of the pipe nut body 14a. The front side frame 6 is also provided with a lower insertion hole 12e through which the pipe nut body 14a is inserted. The front side frame 6 is also provided with a pair of front and rear slits 12f extending from the lower insertion hole 12e.

[0093] With these configurations, the fixing structure of the pipe nut 14 of this embodiment can be inserted into the interior of the front side frame 6 even when the reinforcing plates 14c extend from the pipe nut body 14a. As a result, with the pipe nut body 14a and the reinforcing plates 14c inserted into the interior of the front side frame 6, each reinforcing plate 14c can be easily positioned inside the front side frame 6 simply by rotating the joining flange portion 14b around the central axis O of the pipe nut body 14a. This improves assembly efficiency compared to a case where the pipe nut body 14a is inserted into the front side frame 6 and then the reinforcing members are assembled.

[0094] Each reinforcing plate 14c is joined with the edge of each reinforcing plate 14c in contact with the inner surface of the front side frame 6.

[0095] Specifically, the edge of each reinforcing plate 14c is firmly joined by arc welding while in contact with the inner surface of the inner frame 12. That is, the pipe nut body 14a is firmly joined to the inner surface of the front side frame 6 via each reinforcing plate 14c while being supported by each reinforcing plate 14c. This allows each reinforcing plate 14c to generate sufficient resistance against loads in the prying direction (the direction tilting relative to the central axis) and longitudinal direction that are input to the pipe nut body 14a via the suspension cross member 9 during driving. Therefore, the fixing structure of the pipe nut 14 ensures the attachment rigidity of the pipe nut 14 from the inside of the front side frame 6.

[0096] As described above, each reinforcing plate 14c can be positioned inside the front side frame 6 by inserting it integrally with the pipe nut body 14a from below the front side frame 6. Therefore, even if the connecting flange 14b is provided at the base end of the pipe nut body 14a, the connecting flange 14b does not hinder the assembly of each reinforcing plate 14c. Furthermore, by providing the connecting flange 14b, the connecting flange 14b can abut against the outer surface of the front side frame 6 and restrict longitudinal movement of the pipe nut body 14a. Furthermore, by joining the connecting flange 14b to the outer surface of the front side frame 6 by spot welding, the fixing structure of the pipe nut 14 can ensure the attachment rigidity of the pipe nut 14 even from outside the front side frame 6.

[0097] As a result, the fixing structure of the pipe nut 14 can ensure attachment rigidity by welding from the outside of the front side frame 6 in addition to welding from the inside of the front side frame 6. Therefore, the fixing structure of the pipe nut 14 can increase the attachment rigidity to the front side frame 6.

[0098] Additionally, the front side frame 6 has a pair of upper and lower inner flanges 12d protruding from the outer surface of the front side frame 6. When one of the pair of rotation restricting portions 14h abuts against the inner flange 12d extending from the lower wall portion 12c, each reinforcing plate 14c extends in a direction perpendicular to the longitudinal direction of the front side frame 6. In other words, simply by abutting one of the rotation restricting portions 14h against the inner flange 12d, each reinforcing plate 14c can be positioned accurately to abut against the inner surface of the front side frame 6. This improves the workability when arc-welding each reinforcing plate 14c to the inner surface of the front side frame 6.

[0099] Furthermore, as described above, each reinforcing plate 14c extends in a direction perpendicular to the longitudinal direction inside the front side frame 6. This allows each reinforcing plate 14c to appropriately reinforce the front side frame 6. Therefore, the fixing structure of the pipe nut 14 not only increases the attachment rigidity of the pipe nut 14 to the front side frame 6, but also the rigidity of the front side frame 6.

[0100] Furthermore, each reinforcing plate 14c has a flat plate shape. With this shape, each reinforcing plate 14c can be inserted into the front side frame 6 simply by forming slits 12f in the lower wall portion 12c that correspond to the thickness of each reinforcing plate 14c. This minimizes the number of holes to be formed in each reinforcing plate 14c. Therefore, even in a structure in which the pipe nut body 14a equipped with each reinforcing plate 14c is inserted into the front side frame 6, it is possible to minimize the decrease in rigidity of the lower wall portion 12c.

[0101] [Second embodiment]

[0102] A second embodiment of the present invention is shown in Fig. 7. Components similar to those in the first embodiment are given the same reference numerals, and descriptions thereof will be simplified or omitted.

[0103] The pipe nut body 14 a of the first embodiment is disposed inside the front side frame 6 .

[0104] In contrast, the pipe nut body 14a of this embodiment protrudes upward through the upper wall portion 12b of the front side frame 6. That is, the tip portion of the pipe nut body 14a of this embodiment differs from the pipe nut body 14a of the first embodiment in that it extends further toward the tip side than the pipe nut body 14a of the first embodiment.

[0105] For this reason, the upper wall portion 12b of this embodiment is provided with an upper insertion hole 12g through which the tip end of the pipe nut body 14a is inserted.

[0106] The pipe nut body 14a inserted into such an upper insertion hole 12g is rotatable around the central axis O of the pipe nut body 14a. For this reason, the diameter of the upper insertion hole 12g is set slightly larger than the outer diameter of the pipe nut body 14a.

[0107] The tip side of the pipe nut body 14a, which is inserted into the upper insertion hole 12g, can be joined to the outer surface of the upper wall portion 12b by arc welding while it is inserted into the upper insertion hole 12g.

[0108] As a result, compared to the first embodiment, the fixing structure of this embodiment can generate a stronger resistance to the prying and longitudinal loads input to the pipe nut body 14a via the suspension cross member 9 while driving. Therefore, the fixing structure of this embodiment can further increase the attachment rigidity of the pipe nut 14 to the front side frame 6.

[0109] The other configurations are the same as those in the first embodiment, and therefore the description will be omitted.

[0110] [Third embodiment]

[0111] A third embodiment of the present invention is shown in Figures 8 and 9. Components similar to those in the first and second embodiments are given the same reference numerals, and descriptions thereof will be simplified or omitted.

[0112] The front side frame 6 of this embodiment differs from the first embodiment in that a joint portion 12k that comes into surface contact with one of the pair of reinforcing plates 14c is additionally provided.

[0113] The joint portion 12k protrudes inward from the inner wall portion 12a of the front side frame 6.

[0114] Specifically, as shown in FIG. 9, the joint 12k is provided near the center of the inner wall 12a in the vertical direction of the vehicle body, protruding from the inner wall 12a to the inside of the inner frame 12.

[0115] The joint 12k can be formed from a part of the plate material constituting the inner wall 12a. That is, the joint 12k is formed, for example, by providing a substantially U-shaped notch in a part of the plate material of the inner wall 12a. Then, by bending the base of the formed joint 12k at a substantially right angle toward the inside of the inner frame 12, the joint 12k protrudes into the interior of the front side frame 6. This allows one surface of each reinforcing plate 14c rotated around the central axis O of the pipe nut body 14a to come into surface contact with the joint 12k.

[0116] When reinforcing plate 14c comes into surface contact with joint portion 12k, rotation of pipe nut 14 is restricted. In this manner, joint portion 12k abuts against reinforcing plate 14c and functions as a second protrusion for restricting rotation of pipe nut 14.

[0117] When the reinforcing plates 14c are in surface contact with the joints 12k, each reinforcing plate 14c extends in a direction perpendicular to the longitudinal direction of the inner frame 12.

[0118] Then, in the abutted state, the reinforcing plate 14c is joined to the joint portion 12k by spot welding.

[0119] For example, in this embodiment, spot welding is performed at two locations in the central axis O direction of the pipe nut body 14a with the reinforcing plate 14c in contact with the joint portion 12k.

[0120] With this configuration, the fixing structure of this embodiment can join the reinforcing plate 14c to the front side frame 6 by spot welding. This means that the method of joining the reinforcing plate 14c to the front side frame 6 is not limited to arc welding as described above. Therefore, the fixing structure of this embodiment can further improve the ease of assembling the pipe nut 14 to the front side frame 6, depending on the vehicle model to which it is applied. Note that in this embodiment, the reinforcing plate 14c can be extended in a direction perpendicular to the longitudinal direction of the inner frame 12 simply by being in surface contact with the joint portion 12k, so it is also possible to omit the pair of rotation restricting portions 14h.

[0121] The other configurations are the same as those in the first embodiment, and therefore the description will be omitted.

[0122] The invention described in the above embodiments (first to third embodiments) is not limited to those forms, and various modifications can be made in the implementation stage without departing from the spirit of the invention.

[0123] For example, the fixing structure of the pipe nut 14 described in each of the above embodiments (first to third embodiments) can also be used in the fastening portion between the vehicle body and a seat, or the fastening portion between the vehicle body and a battery case mounted on an electric vehicle.

[0124] Furthermore, the above-mentioned embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining the multiple constituent elements disclosed.

[0125] Furthermore, even if some of the constituent elements are deleted from all the constituent elements shown in the above embodiment, if the stated problem can be solved and the stated effect can be obtained, the configuration from which these constituent elements are deleted can be extracted as an invention. [Explanation of symbols]

[0126] 1. Body 2. Engine room 3. Cabin 4. Toe board 5. Foil apron 6. Front side frame 7. Upper side frame 8. Suspension tower 9. Suspension cross member 12···Inner frame 12a...Inner wall part 12b...Top wall part 12c...Lower wall part 12d···Inner flange 12e...Bottom insertion hole 12f...slit 12g...Top insertion hole 12k...junction 13 Outer frame 13a···Outer flange 14···Pipe nut 14a···Pipe nut body 14b: Joint flange portion (first stopper) 14c Reinforcing plate (second stopper) 14d Boss part 14e Bolt insertion hole 14f Female thread 14g... Seat 14h···Rotation restriction part 15...Hollow section 19 volts 40···Upper panel 40a···Mounting part 40b...Side wall part 40c...First bolt insertion hole 41 Lower panel 41a...Second bolt insertion hole 42 Reinforcement 42a...Third bolt insertion hole 43 Spacer 43a...Fourth bolt insertion hole 45 Arm support 50···Suspension lower arm

Claims

1. A pipe nut fixing structure for fixing a pipe nut body to a vehicle body frame having a hollow cross section, an insertion hole provided in the vehicle body frame, through which the pipe nut body is inserted so as to be rotatable around a central axis of the pipe nut body; a slit provided in the body frame and extending from the insertion hole; a first stopper provided at a base end of the pipe nut body, the first stopper abutting against an outer surface of the vehicle body frame to restrict movement of the pipe nut body in the longitudinal direction; a second stopper extending from a side surface of the pipe nut body, passing through the slit, and disposed inside the vehicle body frame, The pipe nut fixing structure is characterized in that the second stopper is joined to the inner surface of the vehicle body frame at a position rotated around the central axis from the slit.

2. the vehicle body frame has a first protrusion protruding from the outer surface, 2. The pipe nut fixing structure according to claim 1, wherein when the first stopper abuts against the first protrusion, the second stopper extends in a direction perpendicular to the longitudinal direction of the vehicle body frame.

3. the body frame has a second protrusion that protrudes toward an inside of the body frame, 2. The pipe nut fixing structure according to claim 1, wherein when the second stopper abuts against the second protrusion, the second stopper extends in a direction perpendicular to the longitudinal direction of the vehicle body frame.

4. 2. The pipe nut fixing structure according to claim 1, wherein a tip of the pipe nut body penetrates and protrudes through the vehicle body frame.

5. 5. The pipe nut fixing structure according to claim 1, wherein the first stopper is joined to the outer surface of the vehicle body frame by spot welding.

Images