JPS6185207A - Car rear wheel suspension device - Google Patents

Abstract

PURPOSE:To enable a cabin space to be enlarged allowing comfort to be improved by configurating a strut suspension device in such a manner that the position of a strut installation to a wheel support member is located afterward in regard to a car so that a ground contact point is brought close to a line which connects the instantaneous center of motion with the braking center. CONSTITUTION:A rear wheel support spindle 1 is extended afterward in regard to a car, a strut 5 is installed in such a manner that it is offset afterward from the center of the rear wheel Cr so that it is approximately normal to the road surface X. Suspension springs 7 are arranged around the strut in such a way that the center of the springs lies on a line m7 which connects a point of intersection Pr with a strut mounting insulator 6. Here, the point Pr is a point where the perpendicular m6 from the center of the rear wheel Cr to the road surface X intersects the extension line of a radial rod 4. This enables the instantaneous center of motion to be located forward in regard to the car allowing the anti-lift rate to be brought close to 100. Thus, this configuration enables comfort to be improved allowing a cabin space to be enlarged.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a rear wheel suspension system for a motor vehicle, and more particularly to a rear wheel suspension system using struts.

Conventional technology The rear wheel suspension of this rice is used, for example, the service publication published by Nissan Motor Co., Ltd. @ No. 491 "Bluebird"
F as shown in (Publication date October 1982),
F' (front engine front drive) has a bloody rear wheel suspension system. As shown in FIG. 3, a spindle 1 serving as a wheel support member that rotatably supports the wheel
is vertically swingably connected to the vehicle body side (not shown) via a pair of front and rear parallel links 2.3 and a radius rod 4 as an rsa i member.
However, the spindle 1 is further connected to the vehicle body 111 via a strut 5 arranged in the vertical direction of the vehicle. This strut 5 includes an outer shell 5a whose upper end is fixed to the spindle 1, and a shock absorber (not shown) which is housed in the outer cylinder 5 and whose piston rod 5b slidably projects from the upper end of the outer cylinder 5a. The piston rod 5b is mounted on the vehicle body via a mounting insulator 6, which serves as a mounting portion on the piston rod 5b.

7 is a suspension spring that is returned between the outer cylinder 5a and the piston rod 5b.

By the way, in the conventional rear wheel suspension system S, since the wheels are located below the rear seats in the vehicle interior (not shown), the upper end of the strut 5 to the vehicle body, that is, the mounting insulator 6
The struts 5 are moved to the rear of the vehicle and the struts 5 are tilted, thereby arranging the rear seat further to the rear and further expanding the interior space of the vehicle.

Problems to be Solved by the Present Invention However, in such a conventional rear wheel suspension system, it is a problem that the strut 5 is applied to the rear VC#4 of the vehicle. However, the instantaneous center of motion of the wheel during braking, which is determined by the constriction angle of the radius rod 4, is changed, and the anti-lift ratio at the rear of the vehicle becomes significantly less than 100. In other words, to explain this using the schematic diagram of FIG.
and the extension iIMm2 of the radius rod 4. On the other hand, at the braking center during Gtff braking, this braking center G and the grounding point c + + 021 of the front and rear wheels 8 and 9
The braking load Ff is shown on the @ line "3 + "4 connected to
Fr acts. These loads "f" and "Fr" are the cause of the sinking of the front of the vehicle body 1o and the lifting of the rear of the vehicle body 1o.
↓, the anti-lift rate that determines the rise is, as a result, the angle θ formed by the line segment m5 connecting the instantaneous center of motion P and the grounding point e2 of the rear wheel 9 with the road surface X].

The braking center G and the grounding point e! Straight line m4 connecting...
- Determined by (1). This shows that when the anti-lift ratio gilr value is II 00J, there is no partner of lifting and sinking of the Kasuri at the rear of the turret.

However, in the conventional rear wheel suspension r1tSVC described above, since the upper end of the strut 5 is inclined toward the rear of the vehicle, the instantaneous center of motion P approaches the road surface It becomes smaller than θ. Therefore, before! +: Anti-lift rate determined from formula (1) 1t-jr100J is smaller than [2], which clearly indicates that the lifting needle of the rear part of the vehicle body 10 during braking is large, and in this way the Φ body 10 Up and down change 1I7
1 is not very desirable from the viewpoint of ride comfort.

Therefore, in the present invention, the upper end guard gauge 'f:i of the strut is moved to the rear of both sides to expand the interior space of the vehicle, and at the same time, it greatly suppresses the vertical fluctuation it at the rear of the vehicle during braking. Is there a way to achieve the same level of comfort? ctlt
The purpose is to provide a ring SI mounting neck.

Means for Solving the Problems In order to achieve this object, the present invention provides a method for constructing left and right members in which wheel support members that rotatably support wheels are arranged in the left and right direction of the vehicle.
Both A'! 1. Front and rear measuring materials arranged at the rear power rotation, and struts 1 arranged at the top and bottom of the vehicle and attached to the car body at the upper end of the wheel center as seen from the left and right direction. and the instantaneous motion center of the wheel during braking is at the intersection of an extension line extending from the upper end of the strut in the plane angle direction and an extension line of the front and rear measurement members. In the rear wheel suspension of automobiles, which has come to be determined, l11! The lower end of the Ii2 strut to the wheel support member is distributed from the center of the wheel to the rear of the vehicle, and the angle formed by the straight line connecting the instantaneous interlocking center and the ground point of the wheel with the road surface when viewed from the left and right direction of the vehicle is calculated. What is the braking center and wheel grounding point that are determined by engineering the sprung IF center? The S is designed to make the connecting straight lines approach the angle that they form with the road surface, and the anti-lift ratio is made to approach 100.

Example Embodiments of the present invention will be described in detail below with reference to the drawings.

In addition, in fully explaining this embodiment, the same structure as the conventional one will be used.
The same reference numerals are given to the M portions in the description.

That is, FIG. 1 shows an embodiment of the present invention.
9 rear wheels (B), 1 spindle as a retaining ring supporting material that rotatably supports, and 10 pieces (10 pieces) are attached via left and right support members (not shown) disposed in the left and right direction of the vehicle. α with respect to the road surface XK that is connected to the side and arranged in the longitudinal direction of the vehicle.
Radius rod 4 as front and rear welding material with an installation angle of
It is connected to the identity 1O1tll via. Furthermore, mVCn rubber bushings are attached to both the front left and right section members and the radius rod 4, and the wheels 9 are mounted on these rubber bushings.
The gills absorb road excavation transmitted from the to the main body 10 side. The spindle 1 is connected to the main body 101111 via a strut 5 arranged in the vertical direction of the vehicle. An outer cylinder F4 meter is fixedly attached to the spindle 1 on this strut 5 as in the conventional case, and is heated to the vehicle body 10 side via a mounting insulator 6 which serves as a lung with upper end of the piston rod. The mounting insulator 6fl of the strut 5 is disposed at the rear of the vehicle from the center Cr of the rear wheel 9 when viewed from the left-right direction of the vehicle, as in the conventional case, so that the interior space can be expanded.

Here, in this embodiment, as shown in FIG.
The bispindle 1 is extended to both sides, and this extended installation 1ava
The lower end of the strut 5 is fixedly offset from the center Cr of the rear wheel 9, and the strut 5 is arranged so as to be substantially perpendicular to the bumpy road surface X in the vertical direction of the vehicle when viewed from the left and right direction of the vehicle. It is.

Mat5 In this embodiment, a suspension spring 7 is provided on the outer periphery of the strut 5, and the suspension spring 7 is connected to the vertical line m6 of the road surface X passing through the wheel center C7 and the extension line of the radius rod 4. The straight line m7 connecting the intersecting point Pr and the mounting insulator 6 of the strut 5 is arranged as the central axis.

With the above configuration, the rear wheel suspension system S of the present embodiment has the struts 5 standing upright so that the angle with respect to the vertical direction of the vehicle is zero or Fs-1fL<smaller, and the front force of the radius rod 4 being By being slanted upwards,
The vehicle is assisted by -〇 after the instantaneous center of motion P, and
It is set at a position far above and far away from the road surface X. That is, the instantaneous interlocking center Pt1, the extension line m1 extending vertically from the mounting insulator 6 of the strut 5 when viewed from the left-right direction of the vehicle, and the extension IIl of the radius rod 4! ! m2, but since the vertical extension line m1 of the strut 5 is approximately parallel to the road surface X, the instantaneous center of motion P is determined by the intersection with the strut 5
The height h of the mounting insulator 6 is approximately set at the height h of the mounting insulator 6. Therefore, the stratum corneum θ1 formed by the line segment m5 connecting the instantaneous center of motion P and the grounding point e2 of the ground plane X with the road surface X is set larger than in the past.

Next, a line segment m4 connecting the braking center G and the grounding point 02 of the rear wheel 9
Consider the road surface X and the construction angle θ.

That is, when the braking center GH coincides with the sprung center of gravity of the heavy vehicle and the load F during braking acts on the braking center G, the front and rear wheels 8
．． 9, the escape points 61 and 621CH loads Ff and F'r act. The acting direction of these loads Ff and Fr is the braking center G
Acting on the straight line m3 + m4 connecting the ground point e1+82 and the grounding point e1+82, the respective loads Ff, FrF-1 component force ff in the direction parallel to the road surface X and in the vertical direction, ΔW machining component force fr, Δ
Wt - occurring.

Here, it is generally known that the anti-lift rate C of the rear wheels 9 is calculated as follows. (Published by the Society of Automotive Engineers of Japan on June 20, 1981 [New Automotive Engineering Handbook 1 5th wheel @ Chapter 4 1.
1. (see l) r At this time, (L x /F) - r, the center of the rear wheel 9 Cr
The straight line m4 connecting the grounding point e2 of the rear wheel 9 is the corner layer formed with the road surface X by 1 degree, and the straight line m6 connecting the instantaneous movement 1 center P and the above-mentioned ground point e2 is the corner layer formed with the road surface X at θl.

tanθl Therefore, g':: [expressed as 1i1−×100,
6〈100 and'#nilift occurrence barking condition, and ε〉1
When g=100, there is no lift or scatting, and the vehicle posture has changed.1. Shows no barking behavior.

By the way, in this embodiment, the instantaneous center of motion P is on the road surface
Since the angle ta'01 is set above and away from the braking center G, the anti-lift ratio l approaches [00J and the lift il'lk at the rear of the vehicle body IO is reduced.

In this embodiment, the mounting angle of the strut 5 is 1r.
, 11il, thereby increasing the angle θl. However, the present invention is not limited to this, and the mounting angle αK of the radius rod 4 may be adjusted in accordance with the adjustment of the mounting angle of the strut 5.

In addition, the angle adjustment of this radius rod 4, the vertical angle between this radius rod 4 and the front d piston strut 5 [fly*? #nt Is it necessary to avoid being parallel? For example, in this implementation, since the struts 5 are arranged vertically, the radius rod 4 may be avoided from being arranged parallel to the road surface X. Also, due to the installation angle of the radius rod 4, the instantaneous motion center P may be formed on the front side of the vehicle with respect to the rear wheel 9 as shown in this embodiment, or on the contrary, it may be formed on the rear side of the vehicle. In either case, by bringing θ1 closer to 0, the anti-lift ratio can be brought closer to ``girxoo''.

Furthermore, in this example, in addition to the above shown in FIG. 2,
The center 11Bmy of the suspension spring 7 or the vertical line m6 of the road surface X passing through the wheel center C4 and the radius rod 4
An extension of m! Since the intersection point PrtA is ↓, it is possible to reduce the bending moment Th1l[k that acts on the strut 5 when the wheel 9 swings up and down, thereby reducing the sliding resistance of the piston rod 5b. In addition to improving the durability of the parts, the riding comfort can also be improved.

DETAILED DESCRIPTION OF THE INVENTION In the rear wheel suspension system of the present invention, there is provided a wheel support member g of a strut whose upper end is disposed at the rear of the vehicle from the center of the wheel when viewed from the left and right directions of the vehicle.
11 Move the mounting meter to the rear of the vehicle, and measure the angle that the straight line connecting the center of instantaneous motion and the grounding point of the wheel makes with the road surface, and the angle that the straight line connecting the braking center and the wheel grounding point makes with the road surface. Since the anti-lift rate [II 00j
will come close to. Therefore, while securing expansion of the cabin space by placing the upper end addition section 1ft- behind the Ail,
It is possible to reduce vertical fluctuations of the vehicle's head during braking, and to improve both comfort and ride comfort at the same time. Further, by arranging the strut on the side of the wheel support member at the rear of the vehicle from the center of all wheels, the strut can be avoided from the axle shaft in rear wheel drive types including four-wheel drive i. Therefore, even with this sliding type, the lower end ridge of the strut can be placed below the center of the vehicle, reducing the stroke of the shock absorber. It is possible to secure enough # to further increase the number of fishes, which is the same as above.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing one embodiment of the rear wheel suspension system of the present invention, FIG. 2 is an enlarged view of the rear wheel suspension system shown in FIG. 1,
FIG. 3 is a perspective view of a conventional rear wheel suspension system, and FIG. 4 is a schematic diagram of the conventional rear wheel suspension system. 1... Spindle (wheel support material), 2.3... Parallel link (left and right members), 4... Radius rod (
front and rear members), 5... Strut, 6... Mounting insulator (upper end gun attachment), 7... Suspension spring, 9... Rear wheel (1 wheel), 10...
Vehicle body, S...rear wheel suspension system, X...road surface, e2...
- Grounding point, P... IC8G during instantaneous movement... Braking center.

Claims (1)

[Claims] (1) Wheel support members that rotatably support the wheels include left and right members arranged in the left-right direction of the vehicle, front and rear members arranged in the longitudinal direction of the vehicle, and upper end attachment parts to the vehicle body arranged in the up-and-down direction of the vehicle. is connected to the vehicle body side via a strut located behind the wheel center when viewed from the left and right direction of the vehicle, and the instantaneous center of motion of the wheel during braking is perpendicular to the upper end attachment portion of the strut. In the rear wheel suspension system of an automobile, which is determined by the intersection of an extension line extending in the direction of The angle formed by the straight line connecting the instantaneous center of motion and the grounding point of the wheel when viewed from the left and right direction of the vehicle with the road surface is the angle formed by the straight line connecting the braking center determined by the sprung center of gravity of the vehicle and the grounding point of the wheel. A rear wheel suspension system for automobiles that is characterized by an angle close to the road surface.