JPH068149U - Energy absorption type steering device - Google Patents

Abstract

(57) [Summary] [Structure] Connecting members 24e, 24f, and 24i are provided between the bracket 24 of the upper column assembly A2 and the vehicle body side. The connecting members 24e, 24f, 24i connect the upper column assembly A2 to the vehicle body while allowing the displacement of the upper column assembly A2 in the displaceable direction and restricting the displacement in other directions. .. Then, one end is fixed to the connecting member and the other end is fixed to the upper column assembly A2 to provide a bending member 30 that absorbs impact energy. [Effect] While the mounting strength of the upper column assembly A2 is maintained by the bracket 24, the rigidity of the bracket 24 can be prevented from affecting the displacement of the upper column assembly A2 when absorbing impact energy. Therefore, it is possible to maintain sufficient attachment strength and to exhibit the absorption characteristics with high impact energy.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an energy-absorption type steering device, and more particularly, to an energy-absorption type steering device that is capable of absorbing axially applied energy in the axial direction.

[0002]

[Prior art]

 In general, when a large impact is applied to a vehicle while driving, the operator of the vehicle crashes into the steering wheel of the steering system and hits the chest or head. At this time, if the impact energy acting on the steering wheel can be absorbed, the damage to the driver can be reduced as much as possible and the driver's safety can be improved.

Therefore, conventionally, the development of an energy-absorption type steering device capable of absorbing the energy in the axial direction that is shocked to the steering device has been advanced. Such an energy-absorption type steering device has a steering wheel at one end side and is capable of being displaced to the other end side when a predetermined impact is applied in the longitudinal direction from the steering wheel, and an upper column assembly. There is a bracket that holds the assembly on the vehicle body side, and by plastically deforming the bracket when the upper column assembly is displaced, there is one that absorbs impact energy acting on the upper column assembly. (See, for example, JP-A-61-57462).

[0004]

[Problems to be solved by the device]

 In the above-described conventional configuration, since the bracket, which is the supporting member of the upper column assembly, is plastically deformed, if the rigidity of the bracket is too low, the weight of the upper column assembly easily plastically deforms the bracket. It becomes impossible to maintain sufficient mounting strength as a supporting member. On the other hand, if the rigidity of the bracket is too high, even if a large impact is applied to the steering wheel, the bracket acts as a rigid body and cannot absorb the impact energy acting on the upper column assembly.

The present invention has been made in view of the above problems, and provides an energy absorption type steering device capable of maintaining sufficient mounting strength and exhibiting a high impact energy absorption characteristic. The purpose is to do.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the energy-absorption type steering device of the present invention is a steering wheel operated by a driver, an upper steering shaft for fixing the steering wheel at one end side, and a tubular shape for rotatably supporting the upper steering shaft. The upper column tube and an upper column tube fixed to the upper column tube, which includes a highly rigid bracket, are displaceable in the longitudinal direction toward the side opposite to the steering wheel, and are arranged between the bracket and the vehicle body side. , A coupling member for coupling the upper column assembly to the vehicle body while allowing the displacement of the upper column assembly in the direction in which the displacement is possible and restricting the displacement in the other direction, and one end of the coupling member Is fixed to a member and the other end is fixed to the upper column assembly. And a bending member that plastically deforms when the assembly is displaced.

[0007]

[Action]

 According to the energy-absorption type steering device having the above structure, the upper column assembly is connected to the vehicle body side via the bracket having high rigidity, and the displacement of the upper column assembly in a direction other than the longitudinal direction is restricted by the connecting member. Therefore, the assembly strength of the upper column assembly is firmly supported on the vehicle body side by the bracket and the connecting member.

On the other hand, when a predetermined or more impact acts on the displaceable direction of the upper column assembly, the impact energy can be absorbed by the plastic deformation of the bending member. Here, in the above configuration, since the bracket is fixed to the upper column tube and the connecting member is arranged between the bracket and the vehicle body side, the bracket is also displaced as a part of the upper column assembly. As a result, the bending member can be plastically deformed regardless of the rigidity of the bracket.

[0009]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, referring to FIG. 1, which is an overall schematic view of a steering apparatus according to an embodiment of the present invention, the steering apparatus includes a lower column assembly A1 and an upper column assembly A2.

The lower column assembly A 1 is divided into a housing 12 that is held on the vehicle body side via a bracket 11 and a housing 12, and the lower steering shaft 13 extends to one end side and the other end side of the housing 12. A torque sensor 14 mounted on the housing 12 for detecting the rotational torque of the lower steering shaft 13 and a motor 15 for applying an auxiliary rotational torque to the lower steering shaft 13 based on an output signal of the torque sensor 14 are provided. . A boss cylinder 12a is integrally projectingly provided on one end side of the housing 12, and a lower column tube 16 is press-fitted and fixed to the boss cylinder 12a.

The upper column assembly A2 includes a steering wheel 21 operated by a driver, an upper steering shaft 22 for fixing the steering wheel 21 at one end side, and a cylindrical upper column tube rotatably supporting the upper steering shaft 22. 23 and a bracket 24 having a high rigidity fixed to the upper column tube 23. As will be described later in detail, the bracket 23 is displaceable in the longitudinal direction to the side opposite to the steering wheel 21, that is, the lower column assembly A1 side. It is configured .

The steering wheel 21 is a conventional product having a configuration in which the rim 21c is held substantially concentrically via the spokes 21b extending substantially radially from the hub 21a. The upper steering shaft 22 is concentrically fixed to the hub 21a of the steering wheel 21 at one end side, and is concentrically connected at the other end side to the lower steering shaft 13 of the lower column assembly A1 inside the upper column tube 23. It is being touched. Although not specifically shown, the upper steering shaft 22 is connected to the lower steering shaft 13 in a state in which it can be displaced in the axial direction and incapable of being displaced in the rotational direction, and is made of a resin-made fixing agent. The fixing agent is integrally fixed, and the fixing agent is ruptured when a shock larger than a predetermined value is applied to allow the displacement to the side of the lower column assembly A1.

The upper column tube 23 has one end side rotatably supporting the steering shaft 22 via a bearing (not shown) and the other end side connected to the outer circumference of the lower column tube 16 of the lower column assembly A1. Has been done. Although not specifically shown, the upper column tube 23 is connected to the lower column tube 16 via the shaft supporting member in a state in which it can be displaced in the axial direction, so that an impact larger than a predetermined amount is applied. When actuated, it is allowed to be displaced toward the lower column assembly A1 while sliding on the lower column tube 16 via the shaft support member.

As shown in FIG. 2, the bracket 24 is a press-formed product made of sheet metal having a relatively high rigidity, and has a base portion 24 a to be welded to the outer periphery of the upper column tube 23 and a base portion 24 a. And a pair of side plate portions 24b extending from both sides to the side portion. The side plate portion 24b is formed with a recessed portion 24c which extends in the axial direction of the upper column tube 23 and which is substantially rectangular in a plan view and is open on the steering wheel 21 side (right side in FIG. 2). A perforated portion 24d is formed around each recess 24c, and a pair of vertically-opposing connection fittings 24e and 24f are provided on each side plate portion 24b. Each of the connecting fittings 24e, 24f has a long hole 24g facing the recess 24c of the corresponding side plate portion 24b and a hole 24h facing the punching portion 24d, and the resin is cast into the punching portion 24d and the hole 24h. Is integrally connected to the side plate portion 24b, and is also fastened to the vehicle body side by bolts 24i penetrating the concave portions 24c and the elongated hole 24g. The resin cast into the perforated portion 24d and the hole 24h is designed to break. Then, these connecting fittings 24e, 24f, bolts 24i, etc. allow the displacement of the upper column assembly solid A2 in a displaceable direction (direction toward the lower column assembly A1) and displace it in other directions. A connecting member for connecting the upper column assembly A2 to the vehicle body side in a state in which the above is restricted.

In this embodiment, one end is fixed to the connecting member and the other end is fixed to the upper column assembly A2 in the present embodiment, as shown in FIGS. 1, 3, and 4. A bending member 30 that is plastically deformed when the upper column assembly A2 is displaced. As shown in FIG. 3, the bending member 30 is composed of, for example, two sheet metal members formed by punching. The bending member 30 in the present embodiment includes a base end portion 30a fixed to the vehicle body side and a substantially V-shaped energy absorbing portion 30b extending from the base end portion 30a. A bolt hole 30c is formed in the base end 30a, and the bolt 24i is passed through the bolt hole 30c to fasten the base end 30a together with the vehicle body (see FIG. 4). On the other hand, the tip portion 30d of the energy absorbing portion 30b is welded to the end portion of the bracket 24. In this embodiment, the bent portion b of the energy absorbing portion 30b projects outward (downward in FIG. 4) from the bracket 24 in the direction perpendicular to the axial direction of the steering device.

According to the above configuration, the upper column assembly A2 is connected to the vehicle body side via the bracket 24 having high rigidity, and at the same time, by the connecting member composed of the connecting fittings 24e, 24f, the bolt 24i, etc. Since displacement in a direction other than the longitudinal direction is restricted, the assembly strength of the upper column assembly A2 is firmly supported on the vehicle body side by the bracket 24 and the connecting member.

On the other hand, when an impact of a predetermined amount or more acts in the displacement direction of the upper column assembly A2, the resin fixing agent connecting the upper steering shaft 22 to the lower steering shaft 13 and the side plate of the bracket 24. The resin connecting the portion 24b and the connection fittings 24e and 24f is broken. As a result, the upper column assembly A2 is displaced toward the lower column assembly A1. During this displacement process, friction is generated in each of the above-mentioned connecting portions, sliding resistance is generated in the shaft supporting member connecting the upper column tube 23 to the lower column tube 16, and the bending member 30 is bent. The impact energy is absorbed by the plastic deformation of the energy absorbing portion 30b. Here, in the above configuration, since the bracket 24 is fixed to the upper column tube 23 and the connecting member is disposed between the bracket 24 and the vehicle body side, the bracket 24 is also assembled into the upper column assembly. As a result of the displacement as a part of the solid A2, the bending member 30 can be plastically deformed regardless of the rigidity of the bracket 24.

As described above, according to the energy-absorption type steering apparatus of the present embodiment, the mounting strength of the upper column assembly A2 can be maintained by the bracket 24 having high rigidity, and at the time of absorbing the impact energy at the time of collision. In addition, since it is possible to prevent the rigidity of the bracket 24 from affecting the displacement of the upper column assembly A2, the two members share the contradictory effects, which were difficult to achieve at the same time, so that sufficient mounting strength is achieved. It has a remarkable effect that it can be maintained and that it can exhibit absorption characteristics with high impact energy.

In particular, in this embodiment, since the bending member 30 is composed of two sheet metal members, there are advantages that the development width of the parts is relatively small and the material yield is high. Further, since the bent portion b of the energy absorbing portion 30b of the bending member 30 projects outward from the bracket 24 in the direction perpendicular to the axial direction of the steering device, a larger stroke can be obtained. There is also an advantage that a large shock can be absorbed accordingly.

The present invention is not limited to the above embodiment, and various design changes can be made. For example, as shown in FIGS. 5 to 7, a bending member 40 formed of a single press-molded product may be adopted. Referring to FIG. 5, this bending member 40 includes a base end portion 40a fixed to the vehicle body side and an energy absorbing portion 40b extending from the base end portion 40a. A bolt hole 40c is formed in the base end portion 40a, and the bolt 24i (see FIG. 6) is passed through the bolt hole 40c to fasten the base end portion 40a to the vehicle body side together. is doing. On the other hand, the energy absorbing portion 40b is integrally formed on the left and right sides, and forms a pair of concave surfaces 40j along the outer periphery of the bracket 24 on the front end portion 40d side and the base end portion 40a side. Then, with the energy absorbing portion 40b facing the lower column assembly A1 side as shown in FIG. 6 or the steering wheel side as shown in FIG. 7, the tip portion 40d is welded to the bracket 24. By doing so, it is possible to obtain the same effect as that of FIG.

Alternatively, a bending member 50 shown in FIG. 8 and subsequent figures may be adopted. The bending member 50 includes a base end portion 50a fixed to the vehicle body side, a pair of substantially V-shaped energy absorbing portions 50b extending from the base end portion 50a, and a tip end side of each energy absorbing portion 50b. And a connecting portion 50k for connecting. A bolt hole 50c is formed in the base end portion 50a, and the bolt 24i is passed through the bolt hole 50c to fasten the base end portion 50a together with the vehicle body (FIG. 9). reference). On the other hand, the connecting portion 50k of the energy absorbing portion 50b is curved in an arc shape along the outer circumference of the upper column tube 23. Then, as shown in FIG. 9, by welding the connecting portion 50k to the outer periphery of the upper column tube 23, it is possible to obtain the same effect as that of FIG.

Needless to say, it is possible to make various design changes other than the above.

[0023]

[Effect of device]

 As described above, according to the energy-absorption type steering device of the present invention, the mounting strength of the upper column assembly can be maintained by the bracket having high rigidity, and at the time of absorbing the impact energy at the time of collision, the bracket is used. Since it is possible to prevent the rigidity of the upper column assembly from affecting the displacement of the upper column assembly, it is possible to divide the opposing actions, which were difficult to achieve at the same time, between the two members, thus maintaining sufficient mounting strength. Moreover, it has a remarkable effect that it can exhibit the absorption characteristics of high impact energy.

[Brief description of drawings]

FIG. 1 is a schematic view of an energy absorption type steering device according to an embodiment of the present invention.

FIG. 2 is an exploded plan view showing a main part of the above embodiment.

FIG. 3 is a perspective view showing a bending member used in the above embodiment.

FIG. 4 is a partially cutaway enlarged view showing a main part of the above embodiment.

FIG. 5 is a perspective view showing a bending member of another embodiment.

6 is a partially cutaway enlarged view showing a main part of one mode in which the bending member of FIG. 5 is adopted.

FIG. 7 is a partially cutaway enlarged view showing a main part of another aspect in which the bending member of FIG. 5 is adopted.

FIG. 8 is a perspective view showing a bending member of still another embodiment.

9 is a partially cutaway enlarged view showing a main part of one mode in which the bending member of FIG. 8 is adopted.

[Explanation of symbols]

 A2 Upper column assembly 21 Steering wheel 22 Upper steering shaft 23 Upper column tube 24 Bracket 24e Connection fitting (connecting member) 24f Connection fitting (connecting member) 24i Bolt (connecting member) 30 Bending member 40 Bending member 50 Bending member

Claims (1)

[Scope of utility model registration request] 1. A steering wheel operated by an operator,
The other side of the steering wheel includes an upper steering shaft that fixes the steering wheel at one end side, a cylindrical upper column tube that rotatably supports the upper steering shaft, and a highly rigid bracket that is fixed to the upper column tube. Is disposed between the bracket and the vehicle body, and is displaceable in the above displaceable direction, and is displaced in other directions. And a connecting member that connects the upper column assembly to the vehicle body side in a state where the upper column assembly is displaced, and one end is fixed to the connecting member and the other end is fixed to the upper column assembly. An energy-absorption type steering device comprising a bending member that is plastically deformed.