Steering support structure

Abstract

To upgrade the rigidity of a steering unit and suppress a cost.SOLUTION: A steering unit has an instrument panel reinforcement 30 extending in a vehicle width direction. The instrument panel reinforcement 30 includes an outer pipe 10 having an orifice 14 which pierces the instrument panel reinforcement in a radial direction, and an inner pipe 20 arranged into the outer pipe 10. The outer pipe 10 and the inner pipe 20 have their ends in an axial direction or surfaces near the ends partially joined. An internal circumference 13a of the outer pipe 10 and a periphery 20 of the inner pipe 20 (see Fig.1) are joined through welding in the orifice 14 provided in the outer pipe 10.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a steering support structure. [Background technology]

[0002] A steering support beam (instrument panel reinforcement) has been used in vehicles. Specifically, a steering shaft arranged at the driver's seat in a vehicle is supported by a steering support beam that is installed between the left and right front pillars and that spans the front part of the vehicle compartment.

[0003] Cited Document 1 discloses an instrument panel reinforcement having a double structure in which an inner tube is inserted into an outer tube to improve rigidity. The outer tube of this instrument panel reinforcement has a reduced diameter portion formed therein, and the outer tube and the inner tube are fitted together at the reduced diameter portion of the outer tube. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-222157 Summary of the Invention [Problem to be solved by the invention]

[0005] The instrument panel reinforcement disclosed in Patent Document 1 requires a reduced diameter portion in the outer tube. In addition, if the instrument panel reinforcement of Patent Document 1 is applied to a vehicle, the rigidity of the instrument panel reinforcement can be improved, but the dimensions of the instrument panel reinforcement must be designed for each vehicle. In other words, the dimensions and shape of the existing parts must be changed to improve the rigidity, which increases the cost.

[0006] The present invention provides a steering support structure that improves rigidity while suppressing costs. [Means for solving the problem]

[0007] The steering support structure of the present invention is a steering support structure having an instrument panel force extending in the vehicle width direction, the instrument panel force comprising an outer tube having a hole penetrating in the radial direction, and an inner tube arranged within the outer tube, and the outer and inner tubes are joined at their axial ends or at parts of their surfaces near the ends, and the inner circumference of the outer tube and the outer circumference of the inner tube are joined by welding in a hole provided in the outer tube. This makes it possible to improve rigidity through the double tube structure without changing the dimensions and shape of the existing part. Effect of the Invention

[0008] This makes it possible to improve rigidity while suppressing costs. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view showing an outline of a steering support structure before an outer tube and an inner tube are assembled. [Diagram 2] 4 is a perspective view showing an outline of the steering support structure after the outer tube and the inner tube are assembled. FIG. [Diagram 3] FIG. 4 is a side view showing a state in which a plurality of holes are provided in the outer tube. [Figure 4] 1 is an enlarged view showing a state in which a marking line of an inner tube is arranged at the center of a long hole of an outer tube. [Diagram 5] FIG. 4 is a perspective view showing an external force applied to the steering support structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First embodiment Hereinafter, a steering support structure according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view showing an outline of a steering device 1, and shows a state before an outer tube and an inner tube of a steering support beam (hereinafter, referred to as an instrument panel reinforcement) are assembled. Fig. 2 is a perspective view showing an outline of the steering device 1 after the outer tube and the inner tube are assembled.

[0011] As shown in FIG. 1, the steering device 1 includes an instrument panel reinforcement member 30 having an outer tube 10 and an inner tube 20.

[0012] As shown in FIG. 2, the instrument panel reinforcement member 30 has an inner tube 20 attached inside an outer tube 10, thereby forming a double tube structure over substantially the entire width in the longitudinal direction along the axis.

[0013] Returning to Fig. 1, the outer pipe 10 will be described. For example, the outer pipe 10 is a steel pipe. More specifically, the outer pipe 10 has a large diameter portion 11 with a large diameter on one side in the longitudinal direction, and a small diameter portion 12 with a smaller diameter than the large diameter portion 11 on the other side.

[0014] Further, a hollow portion 13 extending in the longitudinal direction is formed in the outer pipe 10. The inner pipe 20 can be inserted into this hollow portion 13. The wall surface forming the hollow portion 13 is referred to as an inner peripheral portion 13a.

[0015] In the following description, the longitudinal direction of the outer tube 10 is referred to as the axial direction or Y direction, and the directions perpendicular to this axial direction are referred to as the radial directions or X and Z directions. Here, the X and Z directions are perpendicular to each other.

[0016] For example, the outer tube 10 is formed with a length of about 1300 mm in the axial direction. The size of the inner diameter of the hollow portion 13 is constant regardless of the large diameter portion 11 and the small diameter portion 12, and can be about 40 mm, but is not limited to this.

[0017] Furthermore, a plurality of holes 14 are formed penetrating the outer pipe 10 in the radial direction. Specifically, the holes 14 are holes penetrating the outer pipe 10 between the outer diameter side and the hollow portion 13 in the radial direction.

[0018] Typically, a plurality of holes 14 are formed in each of the large diameter portion 11 and the small diameter portion 12 of the outer pipe 10. The shape of the holes 14 may be circular from a radial perspective, or may be an elongated hole formed long in the axial direction. Here, Fig. 3 is a side view showing a state in which a plurality of holes 14 are provided in the outer pipe 10. As shown in Fig. 3, the outer pipe 10 is provided with a plurality of circular holes and a plurality of elongated holes as the plurality of holes 14.

[0019] As an example, in the outer pipe 10, the multiple holes 14 are arranged on a straight line in the axial direction. Furthermore, other multiple holes 14 may be arranged on straight lines shifted by about 48° in both directions in the circumferential direction of the outer pipe 10 from the straight line on which the multiple holes 14 are arranged. Typically, the holes 14 are arranged so as to be widely scattered in the axial direction of the outer pipe 10.

[0020] The circular holes 14 may have diameters of 15 mm and 20 mm, and both may be provided. For example, the long holes may have an axial length of 23 mm, but are not limited to these sizes. In other words, the outer tube 10 may have holes 14 of any size at any position.

[0021] A body fastening portion 15 is welded to each of the two ends 10a, 10b of the outer pipe 10. Here, each body fastening portion 15 is a component that is short in the X direction and long in the Z direction. The body fastening portions 15 are fastened to the left and right bodies at the front of the passenger compartment of the vehicle.

[0022] Returning to Fig. 1, the large diameter portion 11 of the outer pipe 10 is provided with a steering attachment portion 16. Here, the steering attachment portion 16 is a component that is short in the Z direction and long in the X direction. A steering shaft is attached to the steering attachment portion 16.

[0023] The inner pipe 20 is a steel pipe. Specifically, the axial length of the inner pipe 20 is approximately the same as that of the outer pipe 10. Furthermore, the outer diameter of the inner pipe 20 is formed to be approximately constant at any position. For example, the outer diameter of the inner pipe 20 is approximately 35 mm. Furthermore, both ends of the inner pipe 20 are referred to as ends 20a and 20b.

[0024] 2, the inner pipe 20 is disposed inside the outer pipe 10. Here, the outer peripheral portion 20c of the inner pipe 20 is brought into contact with the inner peripheral portion 13a of the outer pipe 10 and welded to the hole 14. Typically, the outer peripheral portion 20c of the inner pipe 20 is provided with a marking line extending in the axial direction at a position that matches the long hole of the hole 14 provided in the outer pipe 10.

[0025] Typically, when inserting the inner pipe 20 into the outer pipe 10, the position of the inner pipe 20 is adjusted so that the marking line is located at the center of the long hole. Typically, the position of the inner pipe 20 can be adjusted in the axial and circumferential directions by adjusting the position using this marking line. Figure 4 is an enlarged view of a portion of the instrument panel reinforcement 30 showing a state in which the marking line is located at the center of the long hole.

[0026] The welding of the inner pipe 20 and the outer pipe 10 is performed with the positions adjusted by the marking line. At this time, there may be a difference between the inner diameter of the inner peripheral portion 13a in the hollow portion 13 of the outer pipe 10 and the outer diameter of the outer peripheral portion 20c of the inner pipe 20, causing a gap between the inner peripheral portion 13a and the outer peripheral portion 20c. In this case, welding is performed with the position of the inner pipe 20 in the hollow portion 13 of the outer pipe 10 close to the direction in which the hole 14 is provided.

[0027] Furthermore, with the inner pipe 20 disposed inside the outer pipe 10, an end face of the inner pipe 20 in the axial direction is joined to an end face of the outer pipe 10. That is, the outer pipe 10 and the inner pipe 20 are joined at their respective ends in the axial direction, end 10a and end 20a, and at their respective other ends, end 10b and end 20b. The joining of end 10a and end 20a and the joining of end 10b and end 20b include joining of parts of the surfaces near each end by brazing or the like.

[0028] The inner pipe 20 does not have to be a hollow pipe, but may be rod-shaped. Furthermore, reinforcing the outer pipe 10 with the inner pipe 20 merely requires an additional process of inserting and welding the inner pipe 20 into the outer pipe 10, and does not require any design change to the shape of the outer pipe 10.

[0029] Here, an example of reinforcing the instrument panel reinforcement 30 by disposing the inner pipe 20 inside the outer pipe 10 will be described.

[0030] The amount of change in bending when a force is applied in any direction to an instrument panel reinforcement 30 with only a baseline, in which the inner pipe 20 is not arranged inside the outer pipe 10 as shown in Fig. 1, and a reinforced instrument panel reinforcement 30 with the inner pipe 20 arranged inside the outer pipe 10 as shown in Fig. 2, is shown below. Here, Fig. 5 shows an example of the position and direction of the force applied to the instrument panel reinforcement 30.

[0031] More specifically, the force applied to the instrument panel force 30 is 100 N in the X direction and 100 N in the Z direction to the body fastening portion 15 near the end on the large diameter portion 11 side, and 1000 N in the Z direction to the steering mounting portion 16.

[0032] The table below shows the amount of bending of the instrument panel reinforcement 30 when these forces are applied. The table also shows the strength and the change in mass due to the addition of the inner tube 20. [Table 1]

[0033] That is, the rigidity when a force in the Z direction is applied to the body fastening portion 15 is expected to be improved by approximately 80% by disposing the inner pipe 20 inside the outer pipe 10. Note that, since this force in the Z direction is the direction that is most likely to have an effect among the forces acting on the instrument panel reinforcement 30 in an actual vehicle, this improvement in rigidity in the Z direction is expected to be highly effective when applied to an actual vehicle.

[0034] Therefore, although the weight of the instrument panel reinforcement 30 increases due to the addition of the inner tube 20 inside the outer tube 10, the strength of the instrument panel reinforcement 30 itself can be improved.

[0035] In this way, the rigidity of the instrument panel reinforcement 30 can be improved by inserting the inner pipe 20 into the outer pipe 10 and joining and fixing the end faces of the outer pipe 10 and the inner pipe 20 together. In particular, since there is no need to change the dimensions or shape of the outer pipe 10, which is a prefabricated part, there is no need to redesign the outer pipe 10, and the only additional step is to insert the inner pipe 20, making it possible to improve the rigidity at low cost. Furthermore, when reinforcing the instrument panel reinforcement 30 using this method, there is little impact on the surrounding area, and in particular, the impact on electronic components such as harnesses arranged near the instrument panel reinforcement 30 is suppressed.

[0036] Furthermore, by providing a predetermined number of holes 14 in the outer pipe 10 and welding the outer pipe 10 and the inner pipe 20 through the holes 14, the weld strength between the outer pipe 10 and the inner pipe 20 can be improved.

[0037] The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention. In other words, the above description has been omitted or simplified as appropriate for the purpose of clarity, and a person skilled in the art can easily modify, add, or convert each element of the embodiment within the scope of the present invention.

[0038] For example, the outer pipe 10 and the inner pipe 20 can be joined by welding only their axial ends together, without welding through the hole 14 . [Explanation of symbols]

[0039] 1 Steering device 10 outer tube 10a,10b end 11 Large diameter section 12 Small diameter section 13 Hollow part 13a Inner circumference 14 holes 15 Body fastening part 16 Steering mounting part 20 inner tube 20a,20b end 20c outer periphery 30 Instrument Panel Force

Claims

[Claim 1] A steering support structure having an instrument panel force extending in a vehicle width direction, The instrument panel force is an outer tube having a plurality of holes passing therethrough in a radial direction; an inner tube disposed within the outer tube; The outer tube and the inner tube are joined at their axial ends or at parts of their surfaces near the ends, an inner periphery of the outer tube and an outer periphery of the inner tube are joined by welding in a hole provided in the outer tube, The plurality of holes include a round hole and a long hole extending in the axial direction, The outer tube has: a plurality of holes are arranged on a straight line in one axial direction, and another plurality of holes are arranged on straight lines at different positions in both circumferential directions of the outer tube with respect to the straight line; Steering support structure.

Images