JPS5849895Y2 - Automotive safety handle shaft device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an automobile safety handle shaft device having shock absorbing properties.

Conventionally, the collapsible steering shaft of this type of device has been made by directly joining two shafts having irregularly shaped parts that can be fitted into each other by injection molding of resin.

This structure has the disadvantage that shocks from the wheel side and vehicle vibrations are directly transmitted to the steering wheel, especially when used in combination with a rack and pinion steering gear.

In the present invention, two shafts that can be fitted with a predetermined rotation gap in the odd-shaped fitting part are fixed in the axial direction with an elastic body such as rubber, small torques are transmitted by the elastic body, and torques exceeding a predetermined torque are transmitted by the elastic body. Automotive safety system equipped with a stiff full steering shaft that can transmit shock and vibration through two axes of irregularly shaped parts.
・The purpose is to provide a spindle device.

Next, one embodiment of this invention will be described based on the drawings.A steering shaft connected directly or indirectly to a handle 10 and a steering gear (not shown) has an upper shaft 1
It consists of a lower shaft 3 having a tubular portion and an elastic assembly 2 press-fitted into the fitting portion of both shafts.

The column is fitted with an outer cylinder 4, an inner cylinder 5, and a member 6 for energy absorption, and is fitted onto the steering shaft via upper and lower bearings 8, 9, and rotatably supports the steering shaft. .

Further, the outer cylinder 4 is held by a removable bracket γ on the vehicle body, and when an excessive load is applied to the outer cylinder 4 during a vehicle collision, it moves in the axial direction (downward) and at the joint with the inner cylinder 5. Energy is absorbed by the member 6 for energy absorption.

The upper shaft 1 of the steering shaft is connected to the handle 10, and the lower part thereof is an irregular shaft portion having a non-circular, oval-shaped cross section, so-called irregular cross section, as shown in FIGS. 2 to 4.

The upper part of the lower shaft 3 connected to the steering gear is an irregularly shaped tube part 3A having an inner hole that fits into one irregularly shaped shaft part of the upper shaft, and the lower part thereof is cylindrical.

The tip of one irregularly shaped shaft part fits into the inner hole of the irregularly shaped tube part 3A, and the tip of the irregularly shaped tube part 3A is mated with an elastic body 2B such as rubber.
A wire extension part 2A2 of the elastic assembly 2 consisting of A is fixed by press-fitting.

The inner surface of the elastic body 2B has a modified cross-sectional shape that can be fitted onto the modified shaft portion 1A, and the outer surface is circular.

The mating part 2A is a cylindrical part 2A1 that is fitted onto and adhered to the elastic body 2B.
and a wire extension portion 2A2 formed in the irregularly shaped tube that is press-fitted onto the outer surface of the irregularly shaped tube portion 3A.

Since the elastic body 2B is press-fitted into the irregularly shaped shaft portion 1AK, the upper shaft 1 and the lower shaft 2 are coupled in the axial direction by the frictional force of the press-fitting.

Since this bonding force is not very large, both shafts can contract if an excessive load is applied during a vehicle collision.

The cross-sectional shape of the irregularly shaped shaft part I is such that the flat part thereof is inclined by θ1 symmetrically with respect to the X-X axis perpendicular line in FIG. The torque is transmitted through the elastic assembly 2 up to a predetermined torque,
Torque beyond that is directly transmitted between the irregularly shaped shaft portion 1A and the irregularly shaped tube portion 3A.

Therefore, since the elastic assembly 2 transmits only a small torque, there is no risk of fatigue of the elastic body 2B.

An example of the relationship between the torsion angle and torque of the steering shaft is shown in Figure 6. Between 4 degrees left and right, the torque of the vertical axis is transmitted via the elastic assembly 2, so the so-called torsional rigidity is low. .

Further, as shown in FIG. 5, the wire extension part 2A2 of the elastic assembly 2
Even if the elastic body 2B is press-fitted into the irregularly shaped shaft portion 1A with an appropriate load and the elastic body 2B is press-fitted into the irregularly shaped tube portion 3A, the same characteristics as described above can be obtained.

With the collapsible steering shaft of the present invention constructed as described above, shocks and vehicle vibrations from the wheel side are transmitted in a more relaxed manner than in conventional systems where the upper and lower axles are directly connected and transmit all torque. As a result, even in the event of a vehicle collision, it can collapse in the axial direction in exactly the same way as conventional systems, and the structure is also compact.

Furthermore, if an excessive load is applied to either of the upper and lower axes and even a small amount collapses, the conventional type will collapse as shown in Figure 7.
1 has the disadvantage of breakage and looseness, but the device of the present invention does not have such concerns at all.

In the example, the upper shaft is provided with an irregularly shaped shaft, but this may also be used as the lower shaft.The cross-sectional shape of the irregularly shaped shaft and irregularly shaped tube may be square, pentagonal, etc., instead of the oval shape shown in Fig. 3. It can also be a shape.

[Brief explanation of the drawing]

1 to 6 show an embodiment, and FIG. 1 is a side cross-sectional view showing the entire safety handle shaft device of the present invention. FIG. 2 is an enlarged cross-sectional view of the main part of FIG. 1. FIG. 3 is a diagram showing 2. Fig. 4 is a sectional view taken along the line IV--■ of Fig. 2, and Fig. 5 is a sectional view taken along the line IV--■ of Fig. 2.
The figure is an enlarged sectional view of the main part showing another embodiment of the present invention, Fig. 6 is a characteristic diagram showing the relationship between torsion angle and torque of the embodiment of the present invention, and Fig. 7 is an enlarged sectional view of the main part of the conventional one. It is. Explanation of symbols, 1... Upper shaft, 2... Elastic assembly, 3
... lower shaft, 4 ... outer cylinder, 5 ... inner cylinder, 6 ...
Member for energy absorption, 7... Bracket, 8,
9...Bearing.

Claims (1)

[Scope of utility model registration request] It consists of one shaft 1 having an irregular shaft part 1A with a non-circular cross section at one end, and the other shaft 3 having at one end an irregular tube part 3A that fits around the irregular shaft part 1A. Part 3A
In a steering shaft device for an automobile comprising a steering shaft that fits into the inner hole of the shaft 1 and whose axial length can be reduced by fitting one shaft 1 into the other shaft 3, is formed to be rotatable in both directions by a predetermined angle with respect to the shaft 3, and is bonded to the inner surface of the mating 2A and the mating cylindrical part 2A1 at the fitting part of the irregularly shaped shaft part 1 and the irregularly shaped tube part 3A. The wire extension part 2A2 of the elastic assembly 2 having an irregular cross section consisting of an elastic body 2B is press-fitted into the irregular-shaped shaft part of one shaft, and the elastic body 2B is press-fitted into the irregular-shaped shaft part of the other shaft. An automobile safety handle shaft device characterized in that shafts 1 and 3 are fixed in the axial direction.