JPS5847612A - Trailing arm system suspension - Google Patents

Abstract

PURPOSE:To improve running stability in time of turning around, by tilting two cylindrical elastic bushes of a rear wheel independent suspension to a trailing arm rocking axis, while intersecting high rigidity axes of each of two bushes at the rear of a car body from the rocking axis. CONSTITUTION:A trailing arm 1 is, at forked base ends 1a and 1b, supported by a car body 4 so freely rockable in a vertical direction around a trailing arm rocking axis 6 via cylindrical elastic bushes 2 and 2'. In this case, both or at least one side of these cylindrical elastic bushes 2 and 2' are so arranged that the axis is tilted at the prescribed angle to the trailing arm rocking axis 6 in the horizontal plane. And, these tilting directions and tilt angles are determined so as to cause high rigidity axes 7 and 7' existing in the axial perpendicular direction of each of bushes 2 and 2' to intersect the trailing arm rocking axis 6 at the rear of the car body, to say desirable-intersect at a point Q behind than an energizing point of a wheel 5.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a Trailer Type 8 suspension used for. ``This type of suspension usually has a trailing arm l as shown in FIG. 1, whose proximal end is connected to at least one (usually two) elastic cylindrical pushers 1, 2' and a bracket 3 at /a and /b. .3' is supported on the vehicle body, and a wheel is attached to the tip of the trailing arm l extending toward the rear of the vehicle body! (The wheel shown in the figure is the right rear wheel) is usually mounted rotatably. Thus, the trailing arm
is a common axis 1 at the base end /a, /b with wheel j
The wheel j is swingable in the vertical direction (direction perpendicular to the drawing) around st, and the wheel j is elastically supported by a suspension suspension spring and a shock absorber inserted between the trailing arm l and the vehicle body da.

In a floating trailing arm type suspension, when a lateral external force Fy is applied to wheel j during turning, etc., the trailing arm l mainly pushes the push force along with wheel j.
Due to the elastic deformation of

In the conventional suspension of this type, the rigidity axes of the pushpieces 2 and 2I in the axial direction coincide with the trailing arm swing axis 6, and the pushpieces 12
Since the vertical axes 7.71 in the direction perpendicular to the axis of the bushing 12' are located in the bisecting plane perpendicular to the axis of the bushing 12' and are parallel to each other, the behavior of the trailing arm l and the wheel j during the above displacement is The center is on the trailing arm swing axis iI≦ and the bush λ.

21, and when the trailing arm l and the wheel j receive a lateral external force FY, the wheel j behaves so as to produce a large turning angle +θ in the toe-out direction, as shown by the imaginary line in the figure. .

However, in order to extract sufficient cornering power and to improve running stability during cornering, the turning angle 10 of the wheel j in the toe-out direction due to the lateral external force FY should be made small, preferably when the wheel j is It is preferable to configure the trailing arm type suspension so as to produce a turning angle in the toe-in direction.The present invention improves the trailing arm type suspension to satisfy such requirements. The trailing arm type suspension has seven bushings that are inclined with respect to the trailing arm swing axis in a horizontal plane, and the highly rigid axes of each cylindrical elastic bushing in the direction perpendicular to the axis intersect with the trailing arm swing axis at the rear of the vehicle body. This is what we are trying to provide.

Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

2 to 3 show embodiments of the present invention, in which the same parts as in FIG. 1 are designated by the same reference numerals. In addition,
In Figure 1, the cylindrical elastic pushco,,! I have shown it exposed for convenience, but in reality these bushings 2. λ′ is #!
- As shown in the figures and FIG. Insert it into the space and push it.

-' are fixed to the inner circumferential surfaces of the holes t and r', respectively, and the inner circumferential surfaces are fixed to the outer circumferential surfaces of the sleeves 9 and 9', respectively.

And bolt lO inserted into plastic nut 3.3'.

10' penetrates into the sleeves 9, 9', and the trailing arm l is connected to the vehicle body via a cylindrical elastic pusher at the two pronged base ends /a, /b in the vertical direction around a common axis @6 through λ'. Support swingably.

In the present invention, as shown in FIG. 1, at least one (in the illustrated example, both) of the cylindrical elastic push rods 2/2 is arranged such that its axis is θ0 with respect to the trailing arm swing axis @Is in a horizontal plane. It is arranged so as to be inclined as shown in θ2. Then, these inclination directions and inclination angles θ0. θ2 is
A high-rigidity shaft @7.7' existing in the direction perpendicular to the axis of each pusher -' (Y direction in FIG. It is determined that they intersect at a point Q rearward from the point of impact of j (the center of the contact surface with the road surface).

Moreover, in the present invention, Bushu J,! 9 points P of the high rigidity shaft @7, 7' are not only located closer to the vehicle body than the trailing arm swing axis J14 as described above, but also located outside the vehicle body from the force application point of the wheel j as shown in the figure. IIM angle θ0 of pushco 9.2' so that It is preferable to determine θ2 respectively.

In the suspension of the present invention having such a configuration, the center of rigidity of the pushpieces and wheels in the lateral direction of the vehicle body is a point Q, and when the wheel j receives a lateral external force FY, the pushpieces,
As a result, the trailing arm I and the wheel "3 move around the point Q as the center of the movement. As a result, the trailing arm L and the wheel "3 move around the point Q.In the present invention, the point Q is the trailing arm Because it is located at the rear of the vehicle body from the swing axis 6,
The turning angle +θ in the toe-out direction of the wheel j due to the external force FY in the external structure direction (see Fig. 1) can be reduced, cornering power can be effectively extracted, and running stability during cornering can be improved. O Note that if point Q is located at the rear of the vehicle body than the force application point of wheel j as shown in the illustrated example, when trailing arm l and wheel j receive a lateral external force FY, the wheel! behaves so as to produce a turning angle -θ in the toe-in direction as shown by the imaginary line in Figure 1, making it possible to draw out even more cornering power and further improve running stability when cornering.
Also, if point Q is located outside the vehicle body from the force application point of wheel j as shown in the illustrated example, regardless of whether this intersection point is located in front of the vehicle body or at the rear of the vehicle body from the force application point of wheel j,
By locating the intersection at the rear of the vehicle body with respect to the trailing arm swing axis ≦, the above-mentioned effects can be made more pronounced, which is advantageous. Furthermore, if point Q is located on the outer side of the vehicle body than the force application point of wheel j, the braking force FX in Figure 2 that acts on this wheel at the force application point of wheel j during braking is the wheel! This causes the vehicle to behave in the toe-in direction around point Q, and the vehicle body's strength is increased when braking is applied during turning.

Next, in the above embodiment, the mounting inclination angle θ0 of the bushing 9-' with respect to the trailing arm swing shaft 4I4. θ2
Preferred values are illustratively determined for the following specification values with reference to FIG. Fig. 5 is a diagrammatic transfer of Fig. 2, and the bushes λ and I are drawn as springs. The bushings 2, . 2' mounting inclination angle θ0. It is assumed that θ2 (Fig. 1, Teru Hatake) is also set to the same value as shown by θB in Fig. 5. Further, as shown in FIG. 5, the angle between the trailing arm swing axis II6 and the transverse axis of the vehicle body, which is perpendicular to the longitudinal direction of the vehicle body, is θ', and the eye hole l of the trailing arm l.

From the intersection of the trailing arm swing axis ll116 and the vertical 11iI/2 lowered from the bearing position/2 of the wheel j relative to the tip of the trailing arm l to the trailing arm swing axis 4It, with the distance between 1 and 1 being d. If the distance to the eye hole l' is d2, and the length of the vertical axis is L, then the relationship between the lateral external force FY and the resulting compliance steer angle δ of the wheel j will vary depending on the specifications of the individual vehicle. For example, d□-aOO deception, d2-10 閤, L-4100M
SK2/, -500/2o19/-θ'-3f'
When the specification values are determined as shown in FIG. 7, the change characteristic of the compliance steer angle δ with respect to the mounting inclination angle θ8 of the bushing and coil is determined from the elastic mechanics theory as shown in FIG. In this figure, θB at which the Hunpliance steering angle a becomes maximum is approximately /
It turns out that it is 7 deg, and in this example Bush, 2
．． It can be seen that it is best to set the mounting inclination angle θB of J' to around /7 deg.

FIG. 6 shows another example of the suspension of the present invention viewed from the front of the vehicle. In this example, the cylindrical elastic pushpieces and I in the holes r and r' are connected to the trailing arm in the horizontal plane as shown in FIG. The trailing arm is not only inclined with respect to the swing axis 6, but also in the vertical plane with respect to the trailing arm swing axis @6 as shown by θ3°θ. Then, by selecting the angle of inclination and the direction of inclination as shown in FIG. 4, for example, the highly rigid shaft fllA/39/3' in the direction perpendicular to the axes of the pusher and co' in the vertical direction of the vehicle body is swung by the trailing arm. The lines intersect below the axis, for example at point R.

In this case, the wheel j can be deformed to have a negative camber as shown by α in FIG. This can promote the effect of correcting the cutting angle in the toe-in direction when the vehicle is hit, and the above-mentioned effects can be more pronounced.

In addition, even in the example shown in the figure, each bush, 2
The high rigidity axes @n, /J' in the direction perpendicular to the axes of J' do not necessarily have to intersect, but if they appear to intersect at points Q and R as shown in Figures 1 and 2, that is. If they intersect, the effects of the present invention described above can be achieved.

In addition, the following explanation was given using as an example a semi-trailing arm type suspension in which the pivot axis of the bushing makes a certain angle with respect to the vehicle body (θ' in Fig. 3). It is obvious that the present invention can be similarly applied to a full trailing arm type suspension.

[Brief explanation of drawings]

IN/ is a plan view of a conventional trailing arm suspension, FIG. 2 is a plan view of the trailing arm suspension of the present invention, and FIG. 3 is a cross-sectional view showing the cylindrical elastic bush attachment part. 3 is a perspective view of the same mounting part, FIG. 3 is a line diagram showing the suspension of FIG. 2 and the dimensions of each part, and FIG. FIG. 7 is a characteristic diagram of the compliance steer angle change of the wheel with respect to the bushing mounting inclination angle when the suspension shown in FIG. 2 is used. /...trailing arm, /a, /b...base end, ko. -'...Tubular elastic bushing, J, J'...Bracket, moving axis, 7, 7'...High rigidity axis, t,
t'...eye hole, 9.9'...sleeve, 10. /
θ′...Bolt, Q...Intersection of high rigidity axis Patent applicant Nissan Motor Co., Ltd. Figure 1 Figure 2. 3N No. □ No. 5 G.1 Fig. 6

Claims (1)

[Scope of Claims] L includes a trailing arm, the base end of which is connected to the vehicle body at least at one point via a cylindrical elastic bushing so as to be able to swing vertically around a common axis; In a trailing arm type suspension in which a wheel is rotatably attached to the tip of an arm, at least one of the cylindrical elastic bushes 5 is inclined with respect to the swing axis in a horizontal plane, whereby each cylindrical elastic bush A trailing arm type suspension characterized in that a high-rigidity axis in a direction perpendicular to the axis intersects the swing axis at the rear of the vehicle body. 2. The trailing arm suspension according to claim 1, wherein the high rigidity axes of each cylindrical elastic bushing in the direction perpendicular to the axis intersect at the rear of the vehicle body from the point of application of the wheel. 3. Each cylindrical elastic bushing The trailing arm type % type % according to claim 1 or 2, wherein the high rigidity axis in the direction perpendicular to the axis of the wheel intersects on the outside of the vehicle body from the force application point of the wheel.