JPS6325217B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a spring device, and more particularly, to a coil spring device used in a strut-type suspension device, which prevents body flexing even when the load is eccentric. This invention relates to a coil spring device that does not cause

[Conventional technology]

Conventionally, coil springs used in suspension systems for automobiles and the like include those that are deflected in the axial direction and those that are deflected in the circumferential direction, which are so-called knee-action springs, depending on the type of suspension system. The former is a strut type, the latter is a recessed bone,
The strut type, called a swing axle, is the mainstream of coil spring suspensions. Conventionally, when a compressive load is applied between two plates parallel to the coil spring, the center of the load was designed on the assumption that the center axis of the coil spring coincides with the center axis of the coil spring, and that uniform stress is generated at all positions in the effective part of the coil.

[Problem that the invention seeks to solve]

However, according to actual measurements, when a coil spring of a strut type is compressed between two parallel plates, the center of the load does not coincide with the central axis of the coil spring in most cases, and the eccentricity of this load causes the coil spring to This will cause the torso bending phenomenon. This state is shown in Fig. 1. Fig. 1A shows the coil spring under no load, and the coil spring 1
is subjected to a compressive load between the upper seat 2 and the lower seat 3, but when the compressive load is actually applied, the center of the load does not coincide with the center of the coil spring and shifts to a position slightly deviated from the center of the coil spring. The eccentricity of this load causes the body to bend as shown in FIG. 1B. Then, the stress distribution at that time is
As shown in Figure C, since the sheet receives the coil spring from the end to the first turn, the stress is zero or negligibly small, so the stress distribution is high in the bulge (convex part) of the curved body shape. This results in a wavy distribution with a single turn period in which the concave portion is low (in FIG. 1C, the solid line is the measured value, and the dotted line is the calculated value). This results in
It is understood that the measured stress at the convex part of the wave-like distribution is significantly higher than the calculated stress that does not take eccentric loads into account, and there is a marked tendency for the durability level to be significantly lower than estimated, indicating that there is a drawback in terms of durability. It was hot.

Therefore, the present invention suppresses the generation of bending moment due to eccentric load when a coil spring used in a strut-type suspension is loaded, and reduces the generated stress by eliminating the wave-like distribution of stress distribution in one turn period. The purpose of this is to reduce the number of coil springs and improve the durability of the coil spring.

[Means for solving problems]

In order to achieve the above-mentioned object, the coil spring device used in the strut-type suspension system of the present invention has an upper sheet or One or both of the lower seats are arranged and installed so as to be inclined with respect to the axis of the coil spring in a direction that compresses the bulging side of the body bending due to an eccentric load on the coil spring, and the load on the coil spring is The second invention is characterized in that it is possible to prevent the generation of bending moments caused by eccentric loads that sometimes act. The upper seat and lower seat to be arranged and installed are provided with a boss part that fits into the coil spring, and either or both of the boss part of the upper seat or the boss part of the lower seat is subjected to an eccentric load on the coil spring. An annular spacer whose cross section is inclined in the direction of compressing the bulging side of the body bending is fitted to prevent the generation of a bending moment caused by an eccentric load that acts when the coil spring is loaded. This is its characteristic.

[Effect]

In the coil spring device used in the strut-type suspension system of the present invention, in consideration of body bending due to eccentric loads, either one or both of the upper seat and the lower seat is placed on the bulging side of the body bending of the coil spring. is inclined with respect to the axis of the coil spring in the direction of compression, so even if an eccentric load is applied, the body of the coil spring can be prevented from bending, and the wavy distribution of stress can be eliminated. In the second invention, an annular spacer whose cross section is inclined in the direction of compressing the bulging side of the curved body of the coil spring is fitted into the boss portion of the upper seat or the lower seat, so that eccentric load is not applied to the coil spring. The spacer can prevent the body of the coil spring from bending even if the force is applied to the coil spring.

〔Example〕

A first embodiment of the present invention will be described with reference to FIGS. 2A, B, and C, and the same components will be described using the same reference numerals as in FIG. 1. FIG. 2A shows the state under no load, and FIG. 2B shows the state under load. Reference numeral 1 designates a coil spring used in a strut-type suspension system, and has a predetermined coil diameter and free length. 2 is an upper seat, 3 is a lower seat, and this upper seat 2 and lower seat 3
are disposed at both the upper and lower ends of the coil spring 1 to transmit a compressive load to the coil spring 1. However, in consideration of the bending of the body due to the polarization load in the conventional method described above, the upper sheet 2 and the lower sheet 3 are connected to the coil spring 1. The bulging side of the curved body of the spring is inclined in the direction of compression with respect to the eccentricity of the coil spring.
By doing this, it is possible to prevent the body from bending even when an eccentric load is applied, as shown in Figure 2B. At that time, looking at the stress distribution, the solid line in Figure 2 (C) is the actual measurement. (the dotted line shows the calculated value), the wavy distribution of stress distribution can be eliminated, and the stress can be reduced.

In addition, although the above description has been made regarding the case where both the upper sheet 2 and the lower sheet 3 are inclined in the above-mentioned direction, the above-mentioned inclination can also be achieved by inclining only either the upper sheet 2 or the lower seat 3. It is fully capable of achieving its purpose.

Another embodiment of the present invention will be explained with reference to FIGS. 3A and 3B. FIG. 3A shows the state under no load, and FIG. 3B shows the state under load. Further, the same components will be explained using the same reference numerals as in FIGS. 1 and 2.

1 is a coil spring used in a strut-type suspension device having a predetermined diameter and a predetermined free length; 2 is an upper seat; and 3 is a lower seat;
has a boss portion 2 that fits into the end of the coil spring 1.
and 3 are provided, respectively. 4 and 5
are annular spacers whose cross sections are inclined in the direction of compressing the bulging side of the body bending in consideration of the body bending due to eccentric load in the conventional method of the coil spring 1 described above, and the annular spacers 4,
5 is fitted into the boss portions 2' and 3' of the upper seat 2 and lower seat 3 described above. Therefore, the coil spring 1 is compressed by being sandwiched between the upper sheet 2 and the lower sheet 3 to which the spacers 4 and 5 are respectively fitted, and when loaded, the body is compressed as shown in FIG. 3B. This can prevent bending.

In addition, the annular spacer whose cross section is inclined in the direction of compressing the bulging side of the body bending described above,
Although the spacer has been described as being fitted to both the boss part 2' of the upper sheet 2 and the boss part 3' of the lower seat 3, the spacer can be fitted to either the boss part 2' of the upper sheet 2 or the boss part 3' of the lower seat 3. Even if only one side is fitted, the purpose can be sufficiently achieved.

Fig. 4 shows the coil spring device of the present invention applied to a strut-type suspension system of a vehicle, where 1 is a coil spring used in the strut-type suspension system, 2 is an upper seat, and 3 is a lower seat. The lower seat 3 is arranged so as to be inclined with respect to the axis of the coil spring in a direction that compresses the bulging side of the body bending caused by the eccentric load on the coil spring 1. 6 is a rod, 7 is a shock absorber, and T is a tire. In addition, the direction of the trunk bending is estimated from the calculation results or a load test is performed, so at that stage you can know at which turn from the terminal the bending will take place, so you can either tilt either the upper sheet or the lower sheet, or Decide whether to tilt both sides.

〔Effect of the invention〕

As explained above, the spring device used in the strut-type suspension system of the present invention has an extremely simple structure, and although it is a coil spring used in the strut-type suspension system, it is able to withstand bending moments due to eccentric loads. By suppressing the generation of stress and eliminating the wavy distribution of stress distribution in one turn period, it has the effect of reducing the generated stress and improving the durability of coil springs used in strut type suspension systems. .

[Brief explanation of the drawing]

FIG. 1 shows a conventional example, and FIG.
is a cross-sectional view showing the case without load, B is a cross-sectional view showing the case under load, and C is a stress distribution diagram. Fig. 2 shows the spring device of the present invention, Fig. 2 A and B are cross-sectional views under no load, Fig. 2 C is a stress distribution diagram, and Fig. 3 shows another embodiment according to the present invention. 3A is a cross-sectional view when no load is applied, and FIG. 3B is a cross-sectional view when a load is applied. FIG. 4 is an explanatory diagram in which the spring device of the present invention is applied to a vehicle suspension system. 1: Coil spring, 2: Upper seat, 3: Lower seat, 4, 5: Annular spacer.

Claims (1)

[Scope of Claims] 1. Either or both of the upper seat and the lower seat installed at the upper and lower ends of a coil spring used in a strap-type suspension system can be used to prevent the bulge of body bending due to an eccentric load on the coil spring. The coil spring is arranged and installed so as to be inclined with respect to the axis of the coil spring in the direction of compressing the side thereof, so as to prevent the generation of a bending moment caused by an eccentric load that acts when the coil spring is loaded. A coil spring device featuring: 2. The upper sheet and lower seat installed at both the upper and lower ends of a coil spring used in a strap type suspension system are provided with a boss portion that fits into the coil spring, and the boss portion of the upper sheet or the boss of the lower seat is provided. An annular spacer having an inclined cross section in a direction that compresses the bulging side of the body bending due to an eccentric load on the coil spring is fitted in one or both of the parts, and the spacer acts when the coil spring is loaded. A coil spring device characterized in that it is configured to prevent the generation of bending moments caused by eccentric loads.