GB2135945A

GB2135945A - Independent suspension for non-steered wheels of motor cars

Info

Publication number: GB2135945A
Application number: GB08402935A
Authority: GB
Inventors: Frank Giebel
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1983-02-24
Filing date: 1984-02-03
Publication date: 1984-09-12
Also published as: GB8402935D0; FR2563167A1; DE3306432C2; DE3306432A1; US4556235A; GB2135945B; FR2563167B1

Description

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GB 2 135 945 A

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SPECIFICATION

Independent wheel suspension for non-steered wheels of motor cars

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The invention relates to an independent wheel suspension for non-steered wheels of motor cars, in which a wheel support securely connected to a shock absorber is articulated on the bodywork by 10 way of a transverse arm and a longitudinal arm, the wheel support being connected to a bifurcated outer end of the transverse arm byway of a pin which extends generally in the longitudinal direction of the vehicle and is received in resilient bushes and being 15 pivotably connected to the end of the longitudinal arm by way of resilient buffers.

An independent wheel suspension of this general type is known from German Utility Model GM 71 26 203.

20 In the case of an independent wheel suspension of this type, changes in both the king pin angle and the toe-in, occur as a function of inward and outward springing movements and these in certain circumstances can adversely affect the driving performance. 25 An independent wheel suspension for non-steered wheels of motor cars is known from German Au-slegeschrift No. 28 18 198, in which a suitable design of the resilient bushes which form the pivot bearings for the various arms of the wheel suspension results 30 in the pivotal movements of the wheel being load dependent.

In this case the desired movements of the guided wheel are made possible by an increased yielding capacity of the resilient bushes in the form of 35 corresponding cavities, provided that corresponding forces act upon the arms.

The invention seeks to provide an improved independent wheel suspension in which the toe-in alterations caused by the geometry of the arms may 40 be compensated in an appropriate manner.

According to the present invention, there is provided an independent wheel suspension as set forth above in which the resilient bushes disposed in the transverse arm each comprise a non-uniform outer 45 sleeve and a non-uniform inner sleeve arranged in a specific relationship thereto, and the resilient bushes arranged at the opposite ends of the transverse arm in the direction of travel are inverted through 180° relative each other in such a manner that during 50 inward and outward springing movements the change inthe toe-in caused by the longitudinal arm is compensated by a lateral displacement caused by the rotation of the outer sleeves relative to the inner sleeves.

55 Preferably, the outer sleeve comprises an internal profile which has n concave troughs and the inner sleeve comprises an external profile which has n-1 convex lobes, a resilient material being disposed in the space between the two sleeves, the outer and 60 inner sleeves being arranged in such a manner that in the untwisted state, on one side the lobes are opposite corresponding troughs in a complementary manner, whereas on the diametrically opposite side the lobes are interposed between two adjacent 65 troughs, whereby if the outer sleeve is turned about an angle a lateral movement of the inner sleeve takes place.

The resilient bushes are preferably provided on their outer sleeves with corresponding impressed 70 portions which permit their mounting with correct orientation in the openings of the bifurcated end of the transverse arm and the inner sleeves are provided on one side with one raised portion and on the other side with two raised portions which ensure 75 that during turning about the angle the median axis of the resilient bush moves sideways by a predetermined amount.

The invention will now be described further, by way of example, with reference to the accompanying 80 drawings, in which:

Figure 1 is a side view of an independent wheel suspension according to the invention;

Figure 2 is a rear view of the independent wheel suspension according to Figure 1;

85 Figure 3is a plan view of the axle support and the transverse arm of the independent wheel suspension according to Figure 1;

Figure 4 is a section through a resilient bush in the rest position;

90 Figure 5 is a section through the resilient bush of Figure 4 after pivoting through a specific angle, and

Figure 6 is a section through a further embodiment of a resilient bush.

The independent wheel suspension illustrated in 95 the Figures for a non-steered wheel of a motor car essentially comprises a wheel support 1 which is securely connected to a shock absorber bracket 3 by way of a clamping connection 2. The wheel support 1 is articulated on the bodywork byway of a 100 transverse arm 4 and a longitudinal arm 5, the ends of the arms articulated on the bodywork being pivoted in conventional manner by way of resilient bushes.

In particular, the wheel support 1 is connected in 105 an articulated manner to the outer bifurcated end of the transverse arm 4 by way of a pin 8 which extends generally in the direction of travel of the vehicle and is received in resilient bushes 6 and 7 in the transverse arm 4, and the wheel support 1 is 110 pivotable connected to the rear rod-shaped end of the longitudinal arm 5 byway of resilient buffers 9.

If the independent wheel suspension illustrated in the Figures describes an inward springing movement, that is to say compresssion and elongation of 115 the shock absorber, the longitudinal arm 5 moves through the angle a designated in Figure 1 and at the same time the axis of the shock absorber 3 is deflected through the angle p and the transverse arm 4 is pivoted through the angle y (Figure 2). The 120 deflection of the transverse arm 4through the angle 7 results in a change in the angle of toe-in which should be independent of inward and outward springing movements and as a result, during travel in a straight line over an undulating uneven surface, 125 there occurs undesired roll steer movements of the independent wheel suspension.

Because of the pivoting of the transverse arm through the angle a during up and down movement of the wheel, the outer sleeves of the bushes 6 and 7 130 secured in the transverse arm 4 must be turned with

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GB 2 135 945 A

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respect to their inner sleeves secured on the pin 8 and the wheel support 1, since the shock absorber bracket 3 determines the path of the wheel support 1.

5 The resilient bushes 6 and 7, as illustrated in Figures 4 and 5, comprise a non-uniform outer sleeve 10, a non-uniform inner sleeve 12 and a resilient material 11 arranged in the space between the two sleeves 10 and 11. The sleeve 10 is formed 10 with two inwardly directed lobes 13 which are diametrically opposite one another. A first lobe is arranged directly opposite a first convex lobe 14 projecting from one side of the inner sleeve 12 while the second lobe 13 is arranged symmetrically be-15 tween two further convex lobes 15 projecting from the other side of the inner sleeve 12.

If the outer sleeve 10 is now turned through an angle 8 with respect to the inner sleeve 12, the lobes 13,14 and 15 cooperate with one another in such a 20 waythatthe median axis Aofthe inner sleeve 12 is displaced laterally by an amount X.

Looking now at Figure 3 in which the change in the angle of toe-in caused by articulation of the longitudinal arm 5 is designated 7, it may be clearly seen 25 that when the resilient bushes 6 and 7 are constructed in the manner shown in Figures 4 and 5 are arranged in such a way that the rear resilient bush 6 shifts its inner sleeve in the direction towards the interior of the vehicle (arrow Y) and the front resilient 30 bush 7 shifts its inner sleeve towards the exterior of the vehicle (arrow Z), the change in the toe-in occuring on the wheel as a consequence of the arm arrangement and inward and outward springing movements may be compensated.

35 A further embodiment is shown in Figure 6, in which an outer sleeve 10' is connected to an inner sleeve12' bywayofa resilient material 11'. In this case, the outer sleeve 10' has a circular external profile with a groove 16 to prevent turning and to fix 40 its position. The inner profile comprised four concave troughs 17 and one convex lobe 18. The inner sleeve 12' on the other hand is provided with a receiving bore 19 for a pin and comprises an external profile with three convex lobes 20. 45 The arrangement of the inner sleeve 12' within the outer sleeve 10' is selected to be such that, in the untwisted state, on one side the lobes 20 of the inner sleeve 12' are opposite corresponding troughs 17 of the outer sleeve 10' in a complementary manner 50 whereas on the opposite side the convex lobe 20 is interposed between two adjacent troughs 17 or is opposite a convex lobe 19, respectively.

In addition to the embodiments of the resilient bushes illustrated in Figures 4 and 5 other designs 55 are possible, which result in the intended lateral, displacement of the two sleeves towards one another as a function of a pivoting of the outer sleeve relative to the inner sleeve.

Claims

60 CLAIMS

1. An independent wheel suspension for non-steered wheels of motor cars, in which a wheel support securely connected to a shock absorber is 65 articulated on the bodywork by way of a transverse arm and a longitudinal arm, the wheel support being connected to a bifurcated outer end of the transverse arm byway of a pin which extends generally in the longitudinal direction of the vehicle and is received 70 in resilient bushes and being pivotably connected to the end of the longitudinal arm byway of resilient buffers, wherein the resilient bushes disposed in the transverse arm each comprise a non-uniform outer sleeve and a non-uniform inner sleeve arranged in a 75 specific relationship thereto, and the resilient bushes arranged at the opposite ends of the transverse arm in the direction of travel are inverted through 180° relative each other in such a manner that during inward and outward springing movements the 80 change in the toe-in caused by the longitudinal arm is compensated by a lateral displacement caused by the rotation of the outer sleeves relative to the inner sleeves.

2. An independent wheel suspension according 85 to Claim 1, wherein the outer sleeve comprises an internal profile which has n concave troughs and the inner sleeve comprises an external profile which has n-1 convex lobes, a resilient material being disposed in the space between the two sleeves, the outer and 90 inner sleeves being arranged in such a manner that in the untwisted state, on one side the lobes are opposite corresponding troughs in a complementary manner, whereas on the diametrically opposite side the lobes are interposed between two adjacent 95 troughs, whereby if the outer sleeve is turned about an angle a lateral movement of the inner sleeve takes place.

3. An independent wheel suspension according to Claim 1, wherein the resilient bushes are provided

100 on their outer sleeves with corresponding impressed portions which permit their mounting with correct orientation in the openings of the bifurcated end of the transverse arm and the inner sleeves are provided on one side with one raised portion and on the 105 other side with two raised portions which ensure that during turning about the angle the median axis of the resilient bush moves sideways by a predetermined amount.

4. An independent wheel suspension substan-110 tially as herein described with reference to and as illustrated in the accompanying drawings.

Printed in the UK for HMSO, D8818935,7/84,7102.

Published by The Patent Office, 25 Southampton Buildings, London,

WC2A1 AY, from which copies may be obtained.