JP2002046628A - Steering device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To absorb impact to a vehicle at the time of primary collision without bringing about a rise of the manufacturing costs even in the case a sliding mechanism such as spline fit is required. SOLUTION: A small stiffness part (circular hole 9 and thin part 10) having a small bending stiffness is formed in an upper shaft 5 of an intermediate shaft 3 in the rear part of a vehicle, so that when an impact acts on a universal joint 1 in the front part of the vehicle in the direction behind the vehicle at the time of primary collision of the vehicle, the intermediate shaft 3 folds at the small stiffness part of the upper shaft 5 and the impact will be absorbed. At this time, the impact is first applied to the universal joint 1 in the front part of the vehicle while the place where the small stiffness part is formed lies at the upper shaft 5 of the intermediate shaft 3 in the rear part of the vehicle, so that 'the length of the arm' when impact acts as a bending load is made longer, which allows certain operation to fold at the small stiffness part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates, for example, to a method in which a universal joint on the front side of a vehicle connected to a gear box or the like and a universal joint on the rear side of the vehicle connected to a steering column or the like.
The present invention relates to a vehicle steering device having an intermediate shaft interposed.

[0002]

2. Description of the Related Art For example, in a vehicle steering apparatus disclosed in Japanese Utility Model Publication No. 53-52179, a universal joint on the front side of a vehicle connected to a gear box and the like, and a universal joint on the rear side of the vehicle connected to a steering column and the like. And an intermediate shaft, on which an impact absorbing sleeve having a number of circumferentially long slots is interposed.

[0003] In a primary collision of a vehicle, when an impact acts from the gear box to the intermediate shaft toward the rear of the vehicle, the sleeve is bent at a number of long holes to absorb the impact. It prevents the column and other parts from being pushed up into the vehicle interior.

[0004]

However, depending on the type of vehicle, the distance between the universal joint on the front side of the vehicle and the universal joint on the rear side of the vehicle, that is, the length of the intermediate shaft may be relatively short. .

[0005] Further, in order to adjust the length of the intermediate shaft at the time of assembling to the vehicle and to absorb displacement during traveling of the vehicle, a sliding mechanism such as spline fitting may be provided on the intermediate shaft.

The above-mentioned sleeve for absorbing shock cannot be applied to such an intermediate shaft because the length in the axial direction is increased. In addition, a long slot that is long in the circumferential direction is difficult to press, and causes an increase in manufacturing cost.

[0007] The present invention has been made in view of the above-described circumstances, and the distance between a pair of universal joints is short.
Moreover, even when a sliding mechanism such as spline fitting is required, the impact at the time of the primary collision of the vehicle is reliably absorbed without incurring a rise in the manufacturing cost, and the vehicle is moved into the vehicle interior such as the intermediate shaft. It is an object of the present invention to provide a vehicular steering device capable of reliably preventing thrust of a vehicle.

[0008]

In order to achieve the above object, a vehicle steering system according to the present invention comprises a non-rotating joint between a universal joint at a front side of a vehicle and a universal joint at a rear side of the vehicle. A small rigid portion having a small bending rigidity is formed in a vehicle rear portion of the upper shaft of the intermediate shaft in the vehicle steering device provided with an intermediate shaft including a lower shaft and an upper shaft slidably fitted with each other. It is characterized by.

As described above, according to the present invention, since the small rigid portion having a small bending rigidity is formed at the rear portion of the upper shaft of the intermediate shaft, the impact is transmitted from the gear box during the primary collision of the vehicle. When acting on the shaft toward the rear of the vehicle, the intermediate shaft bends at the small rigid portion of the upper shaft to absorb the impact,
It is possible to prevent the intermediate shaft from being pushed up into the vehicle interior.

In a primary collision of a vehicle, the impact is first applied to the universal joint on the front side of the vehicle, while the small rigid portion bent by the impact is formed in the upper shaft of the intermediate shaft. The rear portion of the vehicle, the "arm length" when the impact acts as a bending load can be lengthened (that is, the bending moment can be increased). The bending can be easily performed, and the bending at the small rigid portion can be performed more reliably.

Further, the intermediate shaft comprises a lower shaft and an upper shaft which are slidable by spline fitting or the like. In the upper shaft, a spline portion is formed at a front portion of the vehicle, and is bent by an impact. The small rigid portion is formed at the rear portion of the vehicle. Therefore, when the length of the intermediate shaft is adjusted at the time of assembling to the vehicle, or when the displacement is absorbed at the time of traveling of the vehicle, the sliding of the lower shaft and the upper shaft is not hindered.

Furthermore, the small rigid portion having a small bending rigidity is realized by forming a circular hole or reducing the thickness of the circular hole, which leads to an increase in manufacturing cost. Not even.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vehicle steering system according to an embodiment of the present invention will be described with reference to the drawings. (First Embodiment) FIG. 1 is a longitudinal sectional view of a vehicle steering device according to a first embodiment of the present invention. FIG.
FIG. 2 is a sectional view taken along line AA of FIG. 1. FIG. 3 is a vertical cross-sectional view of the vehicle steering device shown in FIG. 1 during a primary collision of the vehicle.

As shown in FIG. 1, between a universal joint 1 on the front side of the vehicle connected to a gear box (not shown) and the like, and a universal joint 2 on the rear side of the vehicle connected to a steering column (not shown) and the like. , An intermediate shaft 3 is provided.

The intermediate shaft 3 comprises a tubular small diameter lower shaft 4 and a tubular large diameter upper shaft 5. A male spline 6 formed on the outer peripheral surface at the rear of the lower shaft 4. The spline is fitted with the female spline 7 formed on the peripheral surface,
The two shafts 4 and 5 can slide in the axial direction without rotating each other. This makes it possible to adjust the length of the intermediate shaft 3 when assembling to the vehicle, and to absorb the displacement when the vehicle travels.

The rear end of the upper shaft 5 is press-fitted and fixed to the rubber bush 2a of the universal joint 2. The diameter of the female spline 7 is, for example, about 20 mm.

In the present embodiment, a stopper 8 is provided at the rear portion of the upper shaft 5 such that when the lower shaft 4 enters the upper shaft 5 and the intermediate shaft 3 contracts, the rear end of the lower shaft 4 abuts. It is formed. As shown in FIG. 2, the stopper 8 has an embossed protruding shape protruding toward the inner peripheral side of the upper shaft 5.

In the vicinity of the stopper 8 of the upper shaft 5, four circular holes 9 are formed in a line in the circumferential direction, and a thin portion 10 which is thinner than other portions is formed. The circular hole 9 and the thin portion 10 constitute a small rigid portion having a lower bending rigidity than other portions.

The positional relationship between the stopper 8 and the circular hole 9 in the axial direction is such that the contact point of the stopper 8 with the rear end of the lower shaft 4 is located on the vehicle front side with respect to the center of the round hole 9. It is.

With the above-described configuration, when a primary collision of the vehicle occurs, as shown in FIG. 3, when an impact acts on the universal joint 1 on the front side of the vehicle from a gear box (not shown), the lower shaft 4 is moved. The intermediate shaft 3 contracts by entering the upper shaft 5, and the rear end of the lower shaft 4 comes into contact with the stopper 8.

When this impact acts further toward the rear of the vehicle, the circular hole 9 formed near the stopper 8 and the thin portion 1
0 indicates that the bending rigidity is smaller than that of the other portions, and therefore, the upper shaft 5 has a small rigid portion (the circular hole 9 and the thin portion 1).
Bend at point 0). Thereby, the impact can be absorbed, and the thrust of the intermediate shaft 3 into the vehicle interior can be prevented.

At the time of a primary collision of a vehicle, the impact is applied first to the universal joint 1 on the front side of the vehicle, while a small rigid portion (a circular hole 9 and a thin portion 10) which is bent by the impact is formed. Since the point is a vehicle rear portion of the upper shaft 5 of the intermediate shaft 3, the "arm length" when an impact acts as a bending load can be increased (or the bending moment is increased). As a result, it is easy to bend at the small rigid portion (the circular hole 9 and the thin portion 10), and the bending at the small rigid portion can be performed more reliably.

Further, the intermediate shaft 3 is composed of a lower shaft 4 and an upper shaft 5 which are slidable by spline fitting. In the upper shaft 5, the female spline 7 is formed at a front portion of the vehicle. The small rigid portion (circular hole 9 and thin portion 10) that is bent by an impact is formed at the rear portion of the vehicle. Therefore, when the length of the intermediate shaft 3 is adjusted at the time of assembling to the vehicle or when the displacement is absorbed at the time of traveling of the vehicle, the sliding of the lower shaft 4 and the upper shaft 5 is not hindered.

Further, since the small rigid portion having a small bending rigidity is realized by forming the circular hole 9 or the thin portion 10, the production cost does not increase.

As described above, it is preferable that the universal joint 1 on the front side of the vehicle to which an impact is applied first and the small rigid portion (the circular hole 9 and the thin portion 10) bent by the impact be as far as possible. preferable. Specifically, the distance between the centers of the pair of universal joints 1 and 2 after the contraction of the intermediate shaft 3 due to the impact is about 2
When the distance is 00 mm, the distance between the center of the universal joint 1 on the vehicle front side and the center of the round hole 9 is about 140 mm after contraction.

The distance between the center of the universal joint 1 on the front side of the vehicle and the center of the round hole 9 after the contraction of the intermediate shaft 3 due to the impact depends on the vehicle layout, the strength of the upper shaft 5 (material, outer diameter, hole diameter). , Number of holes, etc.), intermediate shaft 3
Although it depends on the strength required for assembling the vehicle, a minimum of 90 m is preferable for a passenger car and a car of the class.
m is good.

If the distance is smaller than 90 mm, it is difficult to achieve both the strength of the upper shaft 5 and the ease of bending.

Further, by changing the inner and outer diameters of the thin portion 10, the inner diameter and number of the circular holes 9, and the material of the upper shaft 5, the strength required for the upper shaft 5 can be satisfied, and at the time of the primary collision. , Can be easily bent.

The upper shaft 5 is made of, for example, a JIS carbon steel tube for machine structural use STKM15A.
~ STKM17C, the maximum outer diameter of the upper shaft 5 is about 25.4 mm, the outer diameter of the thin part 10 is about 23.4 mm, and the thickness of the thin part 10 is about 1.6 m
m, and the inner diameter of the circular hole 9 is about 5.5 mm.

Further, the circular hole 9 can be punched by a press, and the stopper 8 can be embossed by a press, so that the manufacturing cost can be reduced.

Further, the circular holes 9 are arranged in a line, and can be applied to a case where the space in the axial direction is small.

Further, the inner diameter of the portion where the circular hole 9 of the upper shaft 5 is formed need only be equal to or slightly larger than the large diameter of the female spline 7, and the present invention can be applied even when the space in the radial direction is small. it can. (Second Embodiment) FIG. 4 is a longitudinal sectional view of a vehicle steering system according to a second embodiment of the present invention.

In the second embodiment, the thin portion 10 is thinner than in the first embodiment, but the circular hole 9 is not formed.

In this case as well, at the time of a primary collision of the vehicle, if an impact acts on the universal joint 1 on the front side of the vehicle from a gear box (not shown), the lower shaft 4 enters the upper shaft 5 and the intermediate shaft 3 contracts. Then, the rear end of the lower shaft 4 comes into contact with the stopper 8.

When this impact acts further toward the rear of the vehicle, the thin portion 10 formed in the vicinity of the stopper 8 has a lower bending rigidity than the other portions, so that the upper shaft 5 is connected to the small rigid portion (thin portion). Bend at point 10). Thereby, the impact can be absorbed, and the thrust of the intermediate shaft 3 into the vehicle interior can be prevented.

At the time of the primary collision of the vehicle, the impact is applied first to the universal joint 1 on the front side of the vehicle, while the small rigid portion (thin portion 10) which is bent by the impact is formed. Since the upper shaft 5 of the intermediate shaft 3 is located at the rear of the vehicle, the "arm length" when the impact acts as a bending load can be increased (or the bending moment can be increased). As a result, bending can be easily performed at the small rigid portion (thin portion 10), and the bending at the small rigid portion can be performed more reliably.

Further, in the second embodiment, since the circular holes 9 are not formed, the manufacturing cost can be reduced as compared with the first embodiment, but the outer diameter of the thin portion 10 varies. , Strength and bendability performance vary greatly. Therefore, it is necessary to strictly control the variation, and depending on the size, the manufacturing cost may be increased. (Third Embodiment) FIG. 5 is a longitudinal sectional view of a vehicle steering device according to a third embodiment of the present invention.

In the third embodiment, the vehicle is connected to a gear box (not shown) or the like as shown in FIG. An intermediate shaft 3 is provided between a universal joint 1 on the front side and a universal joint 2 on the rear side of the vehicle connected to a steering column (not shown) or the like.

The intermediate shaft 3 comprises a tubular large-diameter lower shaft 4 and a tubular small-diameter upper shaft 5. A female spline 7 formed on the inner peripheral surface of the rear shaft of the lower shaft 4, and a front part of the upper shaft 5. A spline is fitted with the male spline 6 formed on the outer peripheral surface,
The two shafts 4 and 5 can slide in the axial direction without rotating each other. The front end of the lower shaft 4 is press-fitted and fixed to the rubber bush 1a of the universal joint 1 on the vehicle front side, and the rear end of the lower shaft 4 is caulked to prevent the upper shaft 5 from coming off.

As a small rigid portion having a small bending rigidity,
Four circular holes 9 are formed in the vehicle rear portion of the upper shaft 5, but the thin portion 10 is not formed.

Further, the pin 1 of the universal joint 1 on the front side of the vehicle
b serves as a stopper with which the front end of the upper shaft 5 contacts when the intermediate shaft 3 contracts.

Further, as an example, the upper shaft 5 is made of a JIS carbon steel tube for machine structural use STKM15A.
ＳＴSTKM17C, the maximum outer diameter is about 18 mm, the wall thickness is about 2.6 mm, the inner diameter of the circular hole 9 is about 3 mm, and the number thereof is four.

Also in this case, in the event of a primary collision of the vehicle, if an impact acts on the universal joint 1 on the front side of the vehicle from a gear box (not shown), the lower shaft 4 wraps around the upper shaft 5 and the intermediate shaft 3 contracts. The front end of the upper shaft 5 contacts the pin 1b (stopper) of the universal joint 1.

When this impact acts further toward the rear of the vehicle, the upper shaft 5 bends at the small rigid portion (circular hole 9). This allows the impact to be absorbed,
It is possible to prevent the intermediate shaft 3 from being pushed up into the vehicle interior.

At the time of the primary collision of the vehicle, the impact is first applied to the universal joint 1 on the front side of the vehicle, while the small rigid portion (circular hole 9) which is bent by the impact is formed. Since the upper shaft 5 of the intermediate shaft 3 is located at the rear of the vehicle, the "arm length" when the impact acts as a bending load can be increased (or the bending moment can be increased). As a result, bending can be easily performed at the small rigid portion (circular hole 9), and the bending at the small rigid portion can be performed more reliably. (Fourth Embodiment) In the fourth embodiment, although not particularly shown, the embossed stopper 8 in the second embodiment (FIG. 4) is formed as a groove protruding radially inward over the circumference. ing.

Further, the connection between the tubular large diameter shaft of the intermediate shaft and the yoke of the universal joint is usually press-fitted and fixed before welding in order to improve workability. In this case,
Depending on the force input, the stopper may be deformed,
It is necessary to strictly control the dimensions of males and females or to fit them in gaps.

The present invention is not limited to the above-described embodiment, but can be variously modified. For example, the lower shaft and the upper shaft of the intermediate shaft need only be non-rotatably and slidably fitted to each other.In addition to spline fitting, serrated fitting, two-plane fitting, and polygonal shapes such as triangles. It may be fitting. Further, the first embodiment (FIG. 1)
In this case, the tapered portion 4a of the lower shaft 4 may serve as a stopper. In this case, when the upper shaft 3 contacts the tapered portion 4a, the rear end of the lower shaft 4 It is configured to be located on the vehicle front side from the center.

[0048]

As described above, according to the present invention,
A small rigid portion with low bending stiffness is formed on the rear portion of the upper shaft of the intermediate shaft, so that when an impact is applied from the gearbox to the intermediate shaft toward the rear of the vehicle during a primary collision of the vehicle, the intermediate shaft By being bent at the small rigid portion of the upper shaft, the impact can be absorbed, and the intermediate shaft can be prevented from being pushed up into the vehicle interior.

In the case of a primary collision of the vehicle, the impact is applied first to the universal joint on the front side of the vehicle, while the small rigid portion bent by the impact is formed on the upper shaft of the intermediate shaft. The rear portion of the vehicle, the "arm length" when the impact acts as a bending load can be lengthened (that is, the bending moment can be increased). The bending can be easily performed, and the bending at the small rigid portion can be performed more reliably.

Further, the intermediate shaft comprises a lower shaft and an upper shaft slidable by spline fitting or the like. In the upper shaft, a spline portion is formed at a front portion of the vehicle, and is bent by an impact. The small rigid portion is formed at the rear portion of the vehicle. Therefore, when the length of the intermediate shaft is adjusted at the time of assembling to the vehicle, or when the displacement is absorbed at the time of traveling of the vehicle, the sliding of the lower shaft and the upper shaft is not hindered.

Further, since the small rigid portion having a small bending rigidity is realized by forming a circular hole or reducing the thickness of the portion, the manufacturing cost is increased. Not even.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a vehicle steering device according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a longitudinal sectional view of the vehicle steering device shown in FIG. 1 during a primary collision of the vehicle.

FIG. 4 is a longitudinal sectional view of a vehicle steering device according to a second embodiment of the present invention.

FIG. 5 is a longitudinal sectional view of a vehicle steering device according to a third embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 universal joint on front side of vehicle 1a rubber bush 1b pin 2 universal joint on rear side of vehicle 2a rubber bush 3 intermediate shaft 4 lower shaft 4a taper portion 5 upper shaft 6 male spline 7 female spline 8 stopper 9 circular hole (small rigid portion) 10 Thin part (small rigid part)

Claims (1)

[Claims] 1. A vehicle having an intermediate shaft composed of a lower shaft and an upper shaft interposed non-rotatably and slidably between a universal joint on the front side of the vehicle and a universal joint on the rear side of the vehicle. In the steering device for the, in the vehicle rear portion of the upper shaft of the intermediate shaft,
A steering device for a vehicle, wherein a small rigid portion having a small bending rigidity is formed.