JP2010076541A - Mounting structure of lower rod bracket - Google Patents

Abstract

Provided is a lower rod bracket mounting structure that can alleviate a local stress burden on a side rail side at a fastening portion of a lower rod bracket.
A lower rod bracket (6) is attached to the side rail (1) with an upper end attached to an outer surface of a web of the side rail (1) and extending downward and supporting a lower rod (7) at the lower end. In addition, a connecting member 16 is installed between the portions of the left and right side rails 1 where the upper ends of the lower rod brackets 6 are attached. The bolt is fastened together with the upper end of the bracket 6 by fastening.
[Selection] Figure 1

Description

  The present invention relates to a lower rod bracket mounting structure for supporting a lower rod from the vehicle body side in a vehicle suspension structure.

  FIG. 5 shows an example of a suspension structure in a large vehicle such as a truck or a bus. A vehicle width direction (FIG. 5) is provided below a pair of left and right side rails 1 extending in the longitudinal direction of the vehicle body (left and right direction in FIG. 5). An axle 3 extending in a direction (perpendicular to the drawing in the drawing) and supporting the wheel 2 at both ends thereof is disposed, and a support beam 4 integrally assembled on the lower surface near the end of the axle 3 is disposed. An air spring 5 that absorbs vibration in the vertical direction is interposed between the front and rear end portions and the lower surface of the side rail 1.

  Further, an upper end portion of a lower rod bracket 6 extending downward is attached to the web outer surface of the side rail 1 further forward of the air spring 5 disposed on the front side, and a lower end portion of the lower rod bracket 6 and An intermediate portion of the support beam 4 is tiltably connected by a lower rod 7 that performs front-rear positioning on the lower side of the axle 3.

  However, the example shown here is generally referred to as a lower rod-integrated stabilizer, and each lower rod 7 also serves as an arm of the stabilizer 8 that increases the roll rigidity of the vehicle body. The front end of each lower rod 7 is fixedly attached to both ends of a stabilizer bar 9 of a hollow pipe that is held by rubber bushes at the lower ends of the left and right lower rod brackets 6 and extends in the vehicle width direction.

  That is, the stabilizer bar 9 and each lower rod 7 bridge the left and right wheels 2 in a U shape in plan view. When the left and right wheels 2 move up and down at the same time, the lower rod bracket 6 On the other hand, the stabilizer bar 9 is not symmetrically rotated due to the elastic deformation of the rubber bush, and the stabilizer 8 does not particularly work. However, when the left and right wheels 2 perform different vertical movements due to cornering or the like, the stabilizer bar 9 A torsional moment acts and the reaction force acts to return the left and right wheels 2 to their original positions.

  In addition, since it is difficult to reliably suppress the rotational moment (braking force or driving force) and the lateral displacement moment about the axle 3 with the lower rods 7 alone, The web inner surfaces of the left and right side rails 1 are connected to a bracket (not shown) by a V rod 10 that functions as an upper rod.

  Note that the middle part of the support beam 4 and the side rail 1 immediately above are connected by a shock absorber 11 extending in the vertical direction, and the shock absorber 11 suppresses the back-up of vibration in the vertical direction. Therefore, the vibration is attenuated.

  In the conventional suspension structure configured as described above, as shown in a cross-sectional view in FIG. 6, bolt holes 12 for fastening bolts are formed in upper and lower stages in the upper end portion of the lower rod bracket 6 and the web of the side rail 1. The upper end of the lower rod bracket 6 is fastened to the web outer surface of the side rail 1 by arranging and screwing the nuts 14 through the bolts 13 into the bolt holes 12.

The prior art document information related to this type of lower rod bracket includes the following Patent Document 1.
JP 2003-341325 A

  However, in such a conventional structure, the stress input from the lower rod 7 at the time of propulsion or braking is structured to be easily concentrated on the fastening portion of each lower rod bracket 6 with respect to the side rail 1. There was a problem that the local stress burden on one side was increased.

  In particular, in recent years, the occupied volume of an after-treatment device for purifying exhaust gas has increased, and there is a demand for a compact arrangement space for the suspension structure. There is a demand for downsizing of the part, but such downsizing results in an increase in the surface pressure of the fastening part, and may cause a further increase in the local stress burden on the side rail 1 side in the fastening part. was there.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lower rod bracket mounting structure that can alleviate the local stress burden on the side rail side at the fastening portion of the lower rod bracket. .

  The present invention is a mounting structure for the side rail of a lower rod bracket that is attached to an outer side surface of a side rail and has an upper end extending downward and supporting a lower rod at the lower end thereof. A connecting member is installed between the portions of the rail where the upper end of the lower rod bracket is mounted, and both ends of the connecting member are bolted together with the upper end of the lower rod bracket with the web of each side rail interposed therebetween. It is characterized by being fastened.

  Thus, since the left and right lower rod brackets are directly connected via the connecting member, the stress input from the lower rod during propulsion or braking is applied to the opposite side via the connecting member. Because the stress is transmitted to the side rail and the stress is dispersed and absorbed over a wide range from one side rail to the other side rail, the local stress burden on the side rail side at the fastening part of the lower rod bracket is greatly increased. Will be relaxed.

  Furthermore, in the present invention, it is preferable that the connecting member is formed of an integrally molded product that also serves as a cross member. In this way, the connecting member is generally compared with an existing cross member in which a plurality of parts are assembled. As a result, the number of parts and the number of assembling steps are greatly reduced, so that the work burden can be reduced and the cost can be reduced.

  In addition, when the connecting member is formed of an integrally molded product that also serves as a cross member, it is preferable that an attachment portion for connecting the V rod is formed integrally with the connecting member. Sometimes the stress input from the V rod is also dispersed and absorbed by the side rails via the connecting member, and the brackets for connecting the V rod need not be provided separately. Further reduction is achieved.

  Further, when the connecting member is formed of an integrally molded product that also serves as a cross member, the connecting member is integrally formed with an X rib that intersects in the vertical direction and a rectangular rib that surrounds the X rib as a diagonal line in a rectangular shape. The X ribs and the rectangular ribs are preferably configured so as to form a truss / ramen structure. In this way, the rigidity of the connecting member against the stress transmitted from each lower rod bracket is more effective. Enhanced.

  According to the mounting structure of the lower rod bracket of the present invention described above, various excellent effects as described below can be obtained.

  (I) According to the first aspect of the present invention, the stress input from the lower rod during propulsion or braking is transmitted to the opposite side rail via the connecting member, and the stress is transmitted to one side rail. Can be dispersed and absorbed over a wide range from the other side rail to the side rod side of the lower rod bracket fastening part, so that the local stress burden on the side rail side can be greatly reduced compared to the conventional part. The strength reliability can be greatly improved.

  (II) According to the invention described in claim 2 of the present invention, the number of parts and the number of assembling steps can be greatly reduced as compared with an existing cross member generally assembled with a plurality of parts. The work burden can be reduced and the cost can be significantly reduced.

  (III) According to the invention described in claim 3 of the present invention, the stress input from the V rod during turning can be dispersed and absorbed by the side rails via the connecting member, and the V rod is connected. By eliminating the need for a separate bracket, it is possible to further reduce the number of parts and the number of assembly steps.

  (IV) According to the invention described in claim 4 of the present invention, the rigidity of the connecting member with respect to the stress transmitted from each lower rod bracket can be effectively increased by the truss / ramen structure. Significant weight savings can be achieved by reducing the thickness of the part that contributes less to the surface or omitting it as a reduction hole.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 4 show an example of an embodiment for carrying out the present invention, and portions denoted by the same reference numerals as those in FIGS. 5 and 6 represent the same items.

  As shown in FIGS. 1 to 4, in the mounting structure of the lower rod bracket 6 according to this embodiment, the connecting member 16 is installed between the portions of the left and right side rails 1 where the upper ends of the lower rod bracket 6 are mounted. Both ends of the connecting member 16 are fastened together with a plurality of bolts 13 (see FIGS. 2 and 3) together with the upper end of the lower rod bracket 6 with the web of each side rail 1 interposed therebetween. It has become so.

  That is, in the example shown here, instead of the flange-coupled alligator-type cross member 15 as shown in FIG. 6, the web-coupled integrally formed connecting member 16 is a cross-member. The end of the connecting member 16 and the upper end of the lower rod bracket 6 are fastened together by a plurality of bolts 13.

  Here, at the upper end of the lower rod bracket 6, bolt holes 12 for bolt fastening (see FIGS. 2 and 3) are arranged in two upper and lower stages, and connecting members 16 corresponding to the respective bolt holes 12. Screw holes 17 (see FIGS. 3 and 4) for directly screwing the bolts 13 without using nuts are formed at each position on the side end.

  Further, as shown in detail in FIG. 4, in the vicinity of both ends of the connecting member 16, a mounting portion 18 for connecting the open end of the V rod 10 forms an inclined surface with respect to the vehicle width direction. In addition, an X rib 19 that intersects in the vertical direction and a rectangular rib 20 that surrounds the X rib 19 as a diagonal line in a rectangular shape are integrally formed at the central portion of the connecting member 16. 19 and the rectangular rib 20 are formed so as to form a truss / ramen structure.

  Thus, with this configuration, the left and right lower rod brackets 6 are directly connected via the connecting member 16, so that stress input from the lower rod 7 during propulsion or braking is applied to the connecting member. 16 is transmitted to the opposite side rail 1 through 16 and the stress is dispersed and absorbed over a wide range from one side rail 1 to the other side rail 1. The local stress burden on the one side is greatly relieved.

  Furthermore, in this embodiment, the connecting member 16 is formed as an integrally molded product that also serves as a cross member. Therefore, the number of parts and the number of assembly steps are generally smaller than those of an existing cross member that is generally assembled with a plurality of parts. Will be greatly reduced, and the work burden and cost will be reduced.

  Further, since the connecting member 16 formed as an integrally molded product is integrally formed with a mounting portion 18 for connecting the V rod 10, the stress input from the V rod 10 during turning is also transmitted through the connecting member 16. Since each side rail 1 is dispersed and absorbed, and it is not necessary to separately provide a bracket for connecting the V rod 10, the number of parts and the number of assembling steps can be further reduced.

  Furthermore, in the present embodiment, the connecting member 16 is integrally formed with an X rib 19 that intersects in the vertical direction and a rectangular rib 20 that surrounds the X rib 19 in a rectangular shape with the X rib 19 as a diagonal line. Therefore, the rigidity of the connecting member 16 with respect to the stress transmitted from each lower rod bracket 6 is effectively enhanced by the truss / ramen structure.

  Therefore, according to the above embodiment, the stress input from the lower rod during propulsion or braking is transmitted to the opposite side rail 1 via the connecting member 16, and the stress is transmitted from one side rail 1 to the other side rail. 1 can be dispersed and absorbed over a wide range, so that the local stress burden on the side rail 1 side at the fastening portion of the lower rod bracket 6 can be relieved more than before, and the fastening portion of the lower rod bracket 6 can be reduced. Strength reliability can be greatly improved.

  In addition, since the number of parts and the number of assembly steps can be greatly reduced compared to an existing cross member that is generally assembled with a plurality of parts, the work load can be reduced and the cost can be greatly increased. Reductions can also be realized.

  Furthermore, the stress input from the V rod 10 at the time of turning can also be dispersed and absorbed by the side rails 1 via the connecting member 16, and there is no need to separately provide a bracket for connecting the V rod 10. Further reduction of the number of parts and the number of assembly steps can be achieved.

  Further, since the rigidity of the connecting member 16 with respect to the stress transmitted from each lower rod bracket 6 can be effectively increased by the truss / ramen structure, the portion of the connecting member 16 where the contribution in strength is low is reduced. Or by omitting it as a reduction hole, a significant weight reduction can be achieved.

  The mounting structure of the lower rod bracket of the present invention is not limited to the above-described embodiment. The connecting member does not necessarily have to be formed as an integrally molded product that also serves as a cross member, and the V rod is connected. Needless to say, the mounting portion and the formation of the X rib and the rectangular rib are optional, and various modifications can be made without departing from the scope of the present invention.

It is a top view which shows an example of the form which implements this invention. It is a side view of the fastening site | part of the lower rod bracket of FIG. It is sectional drawing of the III-III arrow of FIG. It is a perspective view which shows the detail of the connection member of FIG. It is a side view which shows an example of the conventional suspension structure. It is sectional drawing of the fastening part of the lower rod bracket of FIG.

Explanation of symbols

1 Side rail 6 Lower rod bracket 7 Lower rod 10 V rod 16 Connecting member 18 Mounting portion 19 X rib 20 Rectangular rib

Claims (4)

  A lower rod bracket mounting structure for the side rail, wherein the lower rod bracket is attached to the outer surface of the web of the side rail and extends downward and supports the lower rod at the lower end thereof. A connecting member is installed between locations where the upper end of the bracket is attached, and both ends of the connecting member are bolted together with the upper end of the lower rod bracket with the web of each side rail interposed therebetween. The lower rod bracket mounting structure is a feature.   The lower rod bracket mounting structure according to claim 1, wherein the connecting member is formed of an integrally molded product that also serves as a cross member.   The lower rod bracket mounting structure according to claim 2, wherein a mounting portion for connecting the V-rod is integrally formed with the connecting member.   An X-rib that intersects vertically and a rectangular rib that surrounds the X-rib in a rectangular shape are integrally formed on the connecting member, and the X-rib and the rectangular rib constitute a truss / ramen structure. The lower rod bracket mounting structure according to claim 2 or 3, wherein

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