NL2008050C2

NL2008050C2 - Wheel axle suspension.

Info

Publication number: NL2008050C2
Application number: NL2008050A
Authority: NL
Inventors: Derk Geert Aalderink; Rutger William Thijhuis; Paulus Kruijer
Original assignee: Vdl Weweler B V
Priority date: 2011-12-28
Filing date: 2011-12-28
Publication date: 2013-07-01
Also published as: CN103182912B; CN103182912A

Description

P31035NL00/CHO

Title: Wheel axle suspension

The present invention relates to a wheel axle suspension for attaching a wheel axle to a vehicle chassis, comprising: - a round tubular axle body, - a flexible trailing arm with a front end that is hingedly coupled to the chassis and 5 which extends crosswise to the axle body, - an axle pad which is arranged between the axle body and the trailing arm, which has a recess in which part of the circumference of the axle body is received, and which has a side facing away from the axle body that engages the trailing arm, - a clamping assembly extending around the axle body for tightening the axle body, 10 the axle pad and the trailing arm together.

Trailing arms of the type used in the invention may be made by rolling, forging or another suitable forming method. They have a resilient portion between the hingedly attached front end, usually constituted by an attachment eye, and the portion where the axle body is attached to it. This resilient portion provides the flexibility to withstand roll 15 movements of the vehicle.

Many examples of wheel axle suspensions of the above mentioned type are known in the art.

The present invention has for an object to provide an alternative wheel axle suspension.

20 This object is achieved by a wheel axle suspension according to claim 1.

According to the invention the axle body is provided with an elongated indent in the region where it is clamped, which indent extends in a longitudinal direction of the axle body. The axle pad has an elongate protrusion located in the recess of the axle pad, which protrusion fits in the indent in the axle body. Furthermore, the axle pad has rigid rear portion 25 which comprises a rear engagement zone which engages on the rear half of the axle body and a front portion, which comprises a front engagement zone which engages on the front half of the axle body. Moreover, the axle pad comprises a flexible intermediate portion interconnecting the front and the rear portion. By this structure the axle pad provides a univocal seating for the axle body, which is allows the compensation of tolerances in the 30 axle shape and dimension. The elongate protrusion of the axle pad, which is received in the elongate indent of the axle body, locks the axle body with respect to the axle pad, such that -2- rotation caused by torsional forces are prevented. The torsional forces may be induced in the axle body by roll movements of the vehicle.

Preferably, the indent - which in a possible embodiment has a substantially cylindrical concave surface - has a front contact surface, a rear contact surface and a bottom surface 5 connecting said front and rear contact surfaces, and the elongate protrusion is shaped in such a way that in the mounted state it only contacts said front and rear contact surfaces of the indent. Preferably the protrusion has a wedge shape. This structure, in which the protrusion has a cross sectional contour which does not correspond with the cross sectional contour of the indent, the protrusion does not make contact with the bottom of the indent, 10 but is as it were clamped between the front and rear contact surfaces. This provides a stable seating of the protrusion in the indent, which does not allow shifting in the tangential direction of the protrusion in the indent. Tolerances in the shape and dimensions of the indent are compensated by the shape of the protrusion. Thereby the protrusion forms a stable supporting point for the axle body.

15 Preferably, the elongate protrusion is located at the rigid rear portion of the axle pad.

The rigid rear portion has sufficient strength to absorb the torsional loads applied to it via the protrusion.

The recess of the axle pad has an axle body facing surface, which axle body facing surface comprises said front and the rear engagement zone, and furthermore has a zone 20 between the front engagement zone and the protrusion where the axle body facing surface and the outer surface of axle body are spaced apart, as well as a zone between the rear engagement zone and the protrusion where the axle body facing surface and the outer surface of axle body are spaced apart.

In a preferred embodiment of the suspension according to the invention the flexible 25 trailing arm is substantially straight at the portion thereof where the axle body is attached to it.

Under the loads occurring in the structure during operation, the axle body with the axle pad will have the tendency to shift rearwards in longitudinal direction of the trailing arm. With such a straight attachment portion of the trailing arm it is necessary to prevent that the 30 axle pad with the axle body will shift since this could cause severe damage and dangerous situations.

In one embodiment which is envisaged for preventing the mentioned shifting of the axle pad and axle body with respect to the trailing arm, the clamping assembly comprises clamping straps as well as a strap plate which lies on a side of the trailing arm opposite the 35 side where the axle pad is located, wherein the strap plate has side portions that extend along the side of the trailing arm towards the axle pad, and wherein the axle pad has transversal lugs, that engage the side portions of the strap plate so as to mutually lock the -3- strap plate and the axle pad in a longitudinal direction of the trailing arm, and wherein the strap plate has at least one locking lug and the trailing arm has at least one recess which receives the locking lug of the strap plate, so as to lock the strap plate with respect to the trailing arm in the longitudinal direction of the trailing arm.

5 In another embodiment which is envisaged for preventing the mentioned shifting of the axle pad and axle body with respect to the trailing arm, the trailing arm has transversely extending ears on either side of the arm, wherein the axle pad has transversal lugs that engage the ears so as to position the axle pad in a predetermined longitudinal position on the trailing arm.

10 The mentioned ears on the trailing arm are preferably each provided with a bore through which passes a shank of a tightening member, preferably a clamping strap.

The mentioned transversal lugs are preferably provided on the rigid rear portion of the axle pad. The rigid rear portion has sufficient strength to absorb the forces applied to it via the lugs as a result of the tendency of the axle pad wit the axle to shift rearwardly.

15 In yet another embodiment which is envisaged for preventing the mentioned shifting of the axle pad and axle body with respect to the trailing arm, the trailing arm is provided with a recessed surface area in its lower side in which a portion of the axle pad is received so as to position the axle pad in a predetermined longitudinal position on the trailing arm.

Another aspect of the invention relates to a wheel axle suspension for attaching a 20 wheel axle to a vehicle chassis, comprising: - a round tubular axle body, - a flexible trailing arm with a front end that is hingedly coupled to the chassis and which extends crosswise to the axle body, - an axle pad which is arranged between the axle body and the trailing arm, which 25 has a recess in which part of the circumference of the axle body is received, and which has a side facing away from the axle body that engages the trailing arm, - a clamping assembly extending around the axle body for tightening the axle body, the axle pad and the trailing arm together, wherein the axle body is provided with an elongated indent in the region where it is 30 clamped, which indent extends in a longitudinal direction of the axle body, wherein the axle pad has an elongate protrusion located in the recess, which protrusion fits in the indent in the axle body, and wherein the indent has a front contact surface, a rear contact surface and a bottom surface connecting said front and rear contact surfaces, wherein the elongate protrusion is 35 shaped in such a way that in the mounted state it only contacts said front and rear contact surfaces of the indent.

-4-

This aspect of the invention, in which the protrusion has a cross sectional contour which does not correspond with the cross sectional contour of the indent, the protrusion does not make contact with the bottom of the indent, but is as it were clamped between the front and rear contact surfaces. This provides a stable seating of the protrusion in the indent, 5 which does not allow shifting in the tangential direction of the protrusion in the indent.

Tolerances in the shape and dimensions of the indent are compensated by the shape of the protrusion. Thereby the protrusion forms a stable supporting point for the axle body.

Preferably, the axle pad has at the recess an axle body facing surface, which does not contact the axle body in the region adjacent the indent. Thus a gap is present between 10 the axle body facing surface and the outer surface of the axle body near the indent. This warrants a more secure abutment of the respective protrusion surfaces on the relevant indent contact surfaces in the axle body.

Yet another aspect of the invention relates to a wheel axle suspension for attaching a wheel axle to a vehicle chassis, comprising: 15 - a round tubular axle body, - a flexible trailing arm with a front end that is hingedly coupled to the chassis and which extends crosswise to the axle body, - an axle pad which is arranged between the axle body and the trailing arm, which has a recess in which part of the circumference of the axle body is received, and which has 20 a side facing away from the axle body that engages the trailing arm, - a clamping assembly extending around the axle body for tightening the axle body, the axle pad and the trailing arm together, wherein the axle body is provided with an elongated indent in the region where it is clamped, which indent extends in a longitudinal direction of the axle body, 25 wherein the axle pad has an elongate protrusion located in the recess, which protrusion fits in the indent in the axle body, wherein the clamping assembly comprises clamping straps as well as a strap plate which lies on a side of the trailing arm opposite the side where the axle pad is located, wherein the strap plate has side portions that extend along the side of the trailing arm 30 towards the axle pad, and wherein the axle pad has transversal lugs, that engage the side portions of the strap plate so as to mutually lock the strap plate and the axle pad in a longitudinal direction of the trailing arm, and wherein the strap plate has at least one locking lug and the trailing arm has at least one recess which receives the locking lug of the strap plate, so as to lock the strap plate with respect to the trailing arm in the longitudinal direction 35 of the trailing arm.

The invention furthermore relates to a vehicle, such as a trailer or al lorry, which comprises a wheel axle suspension as described in the above.

-5-

The invention will be further elucidated in the following detailed description with reference to the drawing, in which:

Fig. 1 shows a view in perspective of a possible embodiment of a wheel axle suspension according to the invention, 5 Fig. 2 shows a view in perspective from below of the wheel axle suspension of Fig. 1,

Fig. 3 shows a side view of the wheel axle suspension of Fig. 1,

Fig. 4 shows a top elevational view of, the suspension of Fig. 1,

Fig. 5A shows a detail of Fig. 1,

Fig. 5B shows a view in perspective from below of a rear part of a trailing arm of the 10 wheel axle suspension of Fig. 1,

Fig. 6A shows a view in perspective from below of a rear part of a trailing arm of an alternative embodiment of a wheel axle suspension of Fig. 1,

Fig. 6B shows a longitudinal section of the wheel axle suspension with the trailing arm of Fig. 6A, 15 Fig. 7 shows a detail in longitudinal section of the locking between the axle body and the axle pad according to the invention,

Fig. 8 shows a top elevational view of another possible embodiment of a wheel axle suspension according to the invention,

Fig. 9 shows a side elevational view of the wheel axle suspension of Fig. 8, 20 Fig. 10 shows a longitudinal section along the line A-A in Fig. 8 of a part of the wheel axle suspension,

Fig. 11 shows a detail D indicated in Fig. 9, and

Fig. 12 shows a detail C indicated in Fig. 10.

25 Figs 1-4 show in different views a possible embodiment of an air-sprung wheel axle suspension according to the invention. For each axle, a wheel axle suspension as shown is provided on either side of the vehicle.

The wheel axle suspension comprises a carrier bracket 1 with two side plates 11.

The carrier bracket 1 is at its upper end attached to the vehicle chassis 10, which is 30 schematically indicated by dashed lines in Fig. 3.

The suspension assembly furthermore comprises a flexible trailing arm 2. The trailing arm 2 has at its front end an attachment eye 21. The trailing arm 2 is hingedly attached to the carrier bracket 1 by a hinge bolt 3 that extends through the attachment eye 21 and bores in the side plates 11 of the carrier bracket 1. Trailing arms of this type may be made by 35 rolling, forging or another suitable forming method. The portion indicated by reference numeral 2 in the Figs 1-3 is resilient and provides the flexibility to withstand roll movements of the vehicle.

-6-

The suspension assembly also comprises an air spring 3 (or bellows), which is attached to a rear end 22 of the trailing arm 2. The air spring 3 has an upper side 31 that is attached to a part of the vehicle chassis 10.

A hollow, relatively thin-walled axle body 4 is provided, which is attached to the 5 trailing arm 2 by means of a clamping assembly. In the shown embodiment the axle body 4 crosses the trailing arm 2 substantially perpendicularly at an attachment portion 25 of the trailing arm. The attachment portion 25, or at least the side 26 of the trailing arm attachment portion 25 that faces the axle body 4 is straight.

An axle pad 5 is provided between the axle body 4 and the trailing arm 2. The axle 10 pad 5 engages at an upper side the lower side of the trailing arm 2. The axle pad 5 has at a side facing away from the trailing arm 2 a recess in which part of the circumference of the axle body 4 is received. This is clearly visible in the Figures 1 and 2.

The clamping assembly comprises clamping straps 6, which in the embodiment shown are formed as substantially U-shaped straps with a front leg 61 and a rear leg 62 15 which are interconnected by a bent portion 63 that extends around the lower half of the circumference of the axle body 4. The legs 61 and 62 of the U-shaped straps 6 have near their free ends a threaded portion which can cooperate with a threaded nut 71, 72 respectively so as to tighten the straps 6, in particular the bent portion 63 thereof against the axle body 4.

20 The clamping assembly also includes a front clamping part which is called a strap plate 8 here. The strap plate 8 extends over the upper side of the trailing arm 2 in the width direction and has two side portions 81 that extend beyond the respective sides of the trailing arm 2. The side portions 81 are provided with through bores through which the front legs 61 of the straps 6 pass. The corresponding nuts 71 that are screwed on the front legs 61 of the 25 straps 6 engage an upper side of the strap plate 8, i.e. the side facing away from the trailing arm. The strap plate 8 thus constitutes a counter element for allowing to tighten the axle 4, the axle pad 5 and the trailing arm 2 together at the front end of the clamping assembly. Because a strap plate 8 is used, there are no through bores necessary in the trailing arm 2 at that location. Thereby the flexible trailing arm 2 is not weakened by bores at a location 30 which during use under road conditions is typically subjected to high loads and stresses.

A damper 9 extends between the strap plate 8 and the carrier bracket 1 and is attached thereto. The damper 9 is not really relevant for the present invention.

The rear legs 62 of the straps 6 are passed through bores 23 (cf. Fig. 2) which are provided in the trailing arm 2 itself. These bores 23 are located just behind the location 35 where the axle body 4 crosses the trailing arm 2.

-7-

The front legs 61 of the straps 6 may have different length than the rear legs 62, depending on the specific structure of the wheel axle suspension. In the embodiment shown in Figs 1-4, the front legs 61 are longer than the rear legs 62.

As can be seen best in Fig. 5B, there is provided at the rear end 22 of the trailing arm 5 on either side an ear 24 which extends transversely. The bores 23 for the rear strap legs 62 are provided in the respective ears 24. The ears 24 have an upper surface which is countersunk with respect to the surrounding parts of the upper side of the rear end 22. The countersunk area allows that the end portion of the rear leg 62 and the corresponding nut 72 are arranged at least partially countersunk in the trailing arm 2. This allows that the bellows 10 3 is positioned more easily in a position overlapping the clamping area between the axle body 4 and the trailing arm 2. In other words, the air spring 3 can be positioned more to the front and the length of the wheel axle suspension is thereby reduced.

The surface area 28 has upstanding lateral sides 28A, visible in Fig. 5B, which retain the axle pad 5 in the lateral direction of the trailing arm.

15 The axle pad 5 has transversal lugs 58 that engage the ears 24 on an engagement surface 27 (cf. Fig. 5A) of the ear 24 so as to position and retain the axle pad 5 in a predetermined longitudinal position on the trailing arm 2.

In Fig 6B is shown in a longitudinal section a rear part of an alternative embodiment of the suspension of Fig. 1. In this embodiment the axle pad 5 does not have the transversal 20 lugs 58 that engage the ears 24 of the trailing arm 2 (cf. Figs 1-3). Instead the trailing arm 2 is provided with a recessed surface area 28 in its lower side. In Fig. 6A the trailing arm 2 of Fig. 6B is shown separately. The recessed area 28 has an upstanding rear edge 29 against which the rear edge 59 of the axle pad 5 abuts. When the axle pad 5, or at least a portion thereof is received in the recessed surface area 28 against the rear edge 29, the axle pad 5 25 is positioned in a predetermined longitudinal position on the trailing arm 2. The recessed surface area 28 has lateral sides 28A, visible in Fig. 6A, which retain the axle pad 5 in the lateral direction of the trailing arm.

In another embodiment, which is not shown it would also be possible that the axle pad has a lug which engages on the front side of the rear leg 62 of the strap 6 to place the 30 axle pad in a predefined longitudinal position on the trailing arm. Possibly there is also a lug provided on the axle pad which engages the rear side of the rear leg 62 of the strap 6. In this way the axle pad is retained in the predefined longitudinal position. By the strap leg 62.

The axle body 4 is provided with an elongated indent 110 in the region where it is attached to the trailing arm 2. The indent 110 constitutes a groove-like recess in the outer 35 surface of the axle body 4. The elongated indent 110 is provided in the axle body 4 by a forming process and extends in a longitudinal direction of the axle body 4.

-8-

As is shown in the cross sectional view of Fig. 7, the indent 110 has a front contact surface 111, a rear contact surface 112 and a bottom surface 113 connecting said front and rear contact surfaces 111, 112. The front contact surface 111, the rear contact surface 112 and the bottom surface 113 together constitute a concave surface of a cylinder segment.

5 As can be best seen in the sectional view of Fig. 6B, the axle pad 5 comprises a rigid rear portion 53 which comprises a rear engagement zone 54 which engages on the rear half of the axle body 4 and a front portion 55 which comprises a front engagement zone 56 which engages on the front half of the axle body 4. The axle pad 5 furthermore comprises a flexible intermediate portion 57 interconnecting the front 55 and the rear portion 53.

10 The axle pad 5 surrounds the axle body 4 on 180° or even more of its circumference (cf. Fig. 6B).

An elongate protrusion 52 is provided on the rear portion 53 of the axle pad 5. It extends in a direction parallel to the longitudinal direction of the axle body and projects from the surface 51 of the recess obliquely downwards to the front. Thus, the indent 110 is on the 15 part of the axle body 4 that is facing rearward and upward. In a suspension with flexible trailing arms, the indent and protrusion are preferably not arranged on the front half of the axle body, because the front half experiences more loads and stresses due to the flexibility of the trailing arm.

The elongate protrusion 52 is a sort of spline or wedge, which is shaped in such a 20 way that in the mounted state it only contacts said front and rear contact surfaces 111 and 112 of the indent 11 as is clearly visible in Fig. 7. The protrusion 52 has thus a cross sectional outer contour that is not entirely complementary to the shape of the indent 110.

The protrusion 52 will not touch the bottom 113 of the indent 110.

In use when the wheel axle suspension is assembled, the tightening force of the 25 straps 6 forces the axle body 4 in the recess of the axle pad 5. The axle pad 5 will tightly engage at the rear half of the axle body 4 with the rear engagement zone 54. Furthermore the elongate protrusion 52 will be pressed in the indent 110. Due to the shape of the protrusion 52 tolerances in the shape of the indent 110 can be compensated. The rear engagement zone 54 and the protrusion 52 provide thus an unequivocal seating for the axle 30 body 4 in the axle pad 5. In the peripheral area between the rear engagement zone 54 and the protrusion 52 a gap 115 is present between the outer surface of the axle body 4 and the concave surface 51 of the axle pad 5.

The seating of the axle body 4 in the axle pad is completed by the front portion 55 of the axle pad is substantially rigid which engages the outer surface of the axle body 4 at a 35 front half of the axle body 4 with the front engagement zone 56. In the peripheral area between the front engagement zone 56 and the protrusion 52 a gap 116 is present between the outer surface of the axle body 4 and the concave surface 51 of the axle pad 5.

-9-

Because the intermediate portion 57 of the axle pad 5 between the rear and front portions 53 and 55 is relatively flexible by making it relatively thin, the axle pad 5 can deform there under the influence of the tightening force. Thereby the axle pad can compensate for tolerances in the size and shape of the axle body 4 and a tight engagement on the axle 5 body at the front engagement zone 56 is secured.

In Figs 8-10 another embodiment of an air-sprung wheel axle suspension according to the invention is shown. This embodiment differs from the embodiment described in the above in that the rear end of the trailing arm is longer and consequently the air spring 3 is positioned at some distance behind the axle body seen in the direction of travel of the 10 vehicle.

The wheel axle suspension of Figs 8-10 comprises a carrier bracket 201 with two side plates 211. The carrier bracket 201 is at its upper end attached to the vehicle chassis 210, which is schematically indicated by dashed lines in Fig. 9.

The suspension assembly furthermore comprises a flexible trailing arm 202. The 15 trailing arm 202 has at its front end an attachment eye 221. The trailing arm 202 is hingedly attached to the carrier bracket 201 by a hinge bolt 203 that extends through the attachment eye 221 and bores in the side plates 211 of the carrier bracket 201.

The suspension assembly also comprises an air spring 203 (or bellows), which is attached to a rear end 222 of the trailing arm 202. The air spring 203 has an upper side 231 20 that is attached to a part of the vehicle chassis 210.

A hollow, relatively thin-walled axle body 204 is provided, which is attached to the trailing arm 202 by means of a clamping assembly. In the shown embodiment the axle body 204 crosses the trailing arm 2 substantially perpendicularly at an attachment portion 225 of the trailing arm. The attachment portion 225 is straight.

25 An axle pad 205 is provided between the axle body 204 and the trailing arm 202.

The axle pad 205 is positioned against the lower side of the trailing arm 202. The axle pad 205 has, at a side facing away from the trailing arm 202, a recess in which part of the circumference of the axle body 204 is received. This is clearly visible in the Figures 9 and 10. About 180° or even more of the circumference of the axle body 204 is received in the 30 recess of the axle pad.

The clamping assembly comprises clamping straps 206, which in the embodiment shown are formed as substantially U-shaped straps with a front leg 261 and a rear leg 262 which are interconnected by a bent portion 263 that extends around the lower half of the circumference of the axle body 204. The legs 261 and 262 of the U-shaped straps 206 have 35 near their free ends a threaded portion which can cooperate with a threaded nut 271, 272 respectively so as to tighten the straps 206, in particular the bent portion 263 thereof against the axle body 204.

- 10-

The clamping assembly also includes a front clamping part 208 and a rear clamping part 216 which will be called a strap plates here.

The front strap plate 208 extends over the upper side of the trailing arm 202 in the width direction and has two side portions 281 that extend beyond the respective sides of the 5 trailing arm 202. The side portions 281 are provided with through bores through which the front legs 261 of the straps 206 pass. The corresponding nuts 271 that are screwed on the front legs 261 of the straps 206 engage an upper side of the strap plate 208, i.e. the side facing away from the trailing arm 202. The strap plate 208 thus constitutes a counter element for allowing to tighten the axle 204, the axle pad 205 and the trailing arm 202 10 together at the front end of the clamping assembly.

A damper 209 extends between the front strap plate 208 and the carrier bracket 201 and is attached thereto. The damper 209 is not really relevant for the present invention.

The rear strap plate 216 also extends over the upper side of the trailing arm 202 in the width direction and has two side portions 282 that extend beyond the respective sides of 15 the trailing arm 202. The side portions 282 are provided with through bores through which the rear legs 262 of the straps 206 pass. The corresponding nuts 272 that are screwed on the front legs 262 of the straps 206 engage an upper side of the strap plate 216, i.e. the side facing away from the trailing arm 202. The strap plate 216 thus constitutes a counter element for allowing to tighten the axle 204, the axle pad 205 and the trailing arm 202 20 together at the rear end of the clamping assembly.

The straps 206 in this embodiment have strap legs 261, 262 with a same length.

The rear strap plate 116 has a locking lug 290 which is received in a recess 291 in the upper side of the trailing arm 202 as is shown in the longitudinal sectional view in Figs 10 and 12. In this way the clamping strap 216 can be positioned in the longitudinal direction 25 of the trailing arm 202 on a predetermined position.

The strap plate 116 has at its side portions 282 that extend along the side of the trailing arm 202 towards the axle pad 205 an engagement portion 283. The axle pad 205 has transversal lugs 258, that engage the engagement portion 283 of the strap plate 216 so as to mutually lock the strap plate 216 and the axle pad 205 in a longitudinal direction of the 30 trailing arm 202. Since the strap plate 216 is locked in longitudinal direction with regard to the trailing arm 202 and the axle pad 205 is positioned and retained in a predetermined way against the engagement surface 283 of the strap plate 116 by means of the rear strap leg 262 and the tightened nut 272, the position of the axle pad 205 with respect to the trailing arm 202, in the longitudinal direction of the trailing arm 202 is secured. In this way the 35 position of the axle body 204 with respect to the longitudinal direction of the trailing arm is predetermined.

-11 -

As can be best seen in the sectional view of Fig. 10, the axle pad 205 comprises a rigid rear portion 253 which comprises a rear engagement zone 254 which engages on the rear half of the axle body 204 and a front portion 255 which comprises a front engagement zone 256 which engages on the front half of the axle body 204. The axle pad 205 5 furthermore comprises a flexible intermediate portion 257 interconnecting the front portion 255 and the rear portion 253.

An elongate protrusion 252 is provided on the rear portion 253 of the axle pad 205. It extends in a direction parallel to the longitudinal direction of the axle body and projects from the surface 251 of the recess obliquely downwards to the front. The elongate protrusion 252 10 is a sort of spline or wedge, which is shaped in such a way that in the mounted state it only contacts said front and rear contact surfaces 111 and 112 of the indent 11 as is clearly visible in Fig. 7. The protrusion 252 has thus a cross sectional outer contour that is not entirely complementary to the shape of the indent 110. The protrusion 252 will not touch the bottom 113 of the indent 110.

15 In use when the wheel axle suspension is assembled, the tightening force of the straps 206 forces the axle body 204 in the recess of the axle pad 205. The axle pad 205 will tightly engage at the rear half of the axle body 204 with the rear engagement zone 254. Furthermore the elongate protrusion 252 will be pressed in the indent 110. Due to the shape of the protrusion 252 tolerances in the shape of the indent 110 can be compensated. The 20 rear engagement zone 254 and the protrusion 252 provide thus an unequivocal seating for the axle body 204 in the axle pad 205. In the peripheral area between the engagement portion zone and the protrusion 252 a gap 115 is present between the outer surface of the axle body 204 and the concave surface 251 of the axle pad 205.

The seating of the axle body 204 in the axle pad is completed by the front portion 25 255 of the axle pad is substantially rigid which engages the outer surface of the axle body 204 at a front half of the axle body 204 with the front engagement zone 256. In the peripheral area between the front engagement zone 256 and the protrusion 252 a gap 116 is present between the outer surface of the axle body 204 and the concave surface 251 of the axle pad 205.

30 Because the intermediate portion 257 of the axle pad between the rear and front portions 253 and 255 is relatively flexible by making it relatively thin, the axle pad 205 can deform there under the influence of the tightening force. Thereby the axle pad 205 can compensate for tolerances in the size and shape of the axle body 204 and a tight engagement on the axle body 204 at the front engagement zone 256 is secured.

35

Claims

Wheel axle suspension for attaching a wheel axle to a vehicle chassis, comprising: - a round tubular axle body (4; 204), - a flexible support arm (2; 202) with a front end (21; 221) pivotally coupled to the chassis and which crosses with respect to the axle body (4; 204), - an axle path (5; 205) arranged between the axle body (4; 204) and the support arm (2; 202), which has a recess in which a part of the circumference of the axle body (4; 204) is received, and which has a side remote from the axle body which engages on the bearing arm (2; 202), - a clamping assembly (6, 71,72, 8; 206, 271, 272, 208, 216) extending around the axle body (4; 204) to clamp together the axle body (4; 204), the axle path (5; 205) and the support arm (2; 202) , wherein the axle body (4; 204) is provided with an elongated indentation (110) in the area where it is clamped, which indentation (110) extends in a longitudinal direction of the axle body ( 4; 204), the axis path (5; 205) having an elongate protrusion (52; 252) located in the recess, which protrusion (52; 252) fits into the indentation (110) in the axle body (4; 204) a stiff rear portion (53; 253) that includes a rear engagement area (54; 254) that engages the rear half of the axle body (4; 204) and a front portion (55; 255) that includes a front engagement area (56; 256) that engages the front half of the axle body (4; 204), and wherein the axle path (5, 205) includes a flexible intermediate portion (57; 257) that includes the front (55; 255) and the rear portion (53 253. connects to each other

The wheel axle suspension according to claim 1, wherein the indentation (110) has a front contact surface (111), a rear contact surface (112) and a bottom surface (113) connecting the front and rear contact surfaces (111, 112), the elongate projection (52; 252) is formed such that, in the mounted state, it only touches the front and rear contact surfaces (111, 112) of the indentation (110).

The wheel axle suspension of claim 2, wherein the indentation (110) has a substantially cylindrical concave surface (111, 112, 113). -13-

Wheel axle suspension according to one of the preceding claims, wherein the recess of the axle path (5; 205) has a surface (51; 251) facing the axle body, which surface (51; 251) facing the axle body has the front and rear engagement area (56; 54, 256, 254), and further has an area between the front engagement area (56, 256) and the protrusion (52; 252) where the axle body surface (51; 251) and the outer surface of the axle body (4; 204) are spaced apart, as well as an area between the rear engagement area (54; 254) and the protrusion (52; 252) where the surface (51; 251) facing the axle body and the outer surface of the axle body (4; 204) are spaced apart from each other. 10

The wheel axle suspension according to any of the preceding claims, wherein the flexible support arm (2, 202) is substantially straight at the portion (25; 225) thereof to which the axle body (4; 204) is attached.

Wheel axle suspension according to one of the preceding claims, preferably according to claim 5, wherein the clamping assembly comprises clamping straps, as well as a sling plate (216) located on one side of the support arm (202) opposite the side where the axle path (205) is located wherein the slider plate (216) has side portions (282) extending along the side of the support arm (202) in the direction of the axle pad (205), and wherein the axle pad (205) has transverse lugs (251) that engage on the side portions of the sling plate (216) for mutually locking the sling plate (116) and axle pad (205) in a longitudinal direction of the support arm (202), and wherein the sling plate has at least one locking cam (290) and the support arm is at least has a recess (291) that receives the locking cam (290) of the sling plate (216) to secure the sling plate (216) relative to the support arm 25 (202) in the longitudinal direction of the support arm (202).

The wheel axle suspension according to any of claims 1-5, wherein the carrying arm (2) has transversely extending lugs (24) on each side of the arm (2), and wherein the axle path (5) has transverse lugs (58) which engage ears (24) to position the axle path (5) at a predetermined longitudinal position on the support arm (2).

Wheel axle suspension according to claim 7, wherein the lugs (24) are provided with a bore (23) through which a shank (62) extends through a tensioning member (6), preferably a clamping strap. 35

The wheel axle suspension according to claim 7 or 8, wherein the transverse lugs (58) are provided on the rigid rear portion (53) of the axle path (5). -14-

Wheel axle suspension according to one of the preceding claims, wherein the bearing arm is provided with a recessed surface area (28) on the underside, in which a part of the axle path (5) is received around the axle path (5) in a predetermined longitudinal position on the position the bearing arm (2). 5

Wheel axle suspension according to one of the preceding claims, wherein the elongated protrusion (52; 252) is located on the rigid rear portion (53; 253) of the axle path (5; 205).

A wheel axle suspension for attaching a wheel axle to a vehicle chassis, comprising: - a round tubular axle body (4; 204), - a flexible support arm (2; 202) with a front end (21; 221) pivotally coupled to the chassis and which extends crosswise with respect to the axle body (4; 204), - an axle path (5; 205) arranged between the axle body (4; 204) and the support arm (2; 202), which has a recess has a part of the circumference of the axle body (4; 204) accommodated and which has a side remote from the axle body which engages the support arm (2; 202), 20. a clamping assembly (6, 71, 72, 8 ; 206, 271, 272, 208, 216) extending around the axle body (4; 204) to clamp the axle body (4; 204), the axle pad (5; 205) and the support arm (2; 202) together, wherein the axle body (4; 204) is provided with an elongated indentation (110) in the area where it is clamped, which indentation (110) extends in a longitudinal direction of the axle body (4; 204), the axis path (5; 205) having an elongate protrusion (52; 252) located in the recess, which protrusion (52; 252) fits into the indentation (110) in the axle body (4; 204) and wherein the indentation (110) has a front contact surface (111), a rear contact surface (112) and a bottom surface (113) connecting the front and rear contact surfaces (111), the elongated protrusion (52) being on a is formed such that, in the mounted state, it only touches the front and rear contact surfaces (111, 112) of the indentation (110).

Wheel axle suspension for attaching a wheel axle to a vehicle chassis, comprising: - a round tubular axle body (204), - a flexible support arm (202) with a front end (221) pivotally coupled to the chassis and which extending crosswise with respect to the axle body (204), - an axle path (205) arranged between the axle body (204) and the support arm 5 (202), which has a recess in which a portion of the circumference of the axle body (204) ) and has a side remote from the axle body that engages the support arm (202), - a clamping assembly (206, 271, 272, 208, 216) extending around the axle body (204) about the axle body (204 ), clamp the axle pad (205) and the carrying arm (202) together, the axle body (204) being provided with an elongated indentation (110) in the area where it is clamped, which indentation (110) extends in a longitudinal direction extending from the axle body (204), the axle path (205) extending longitudinally has a protrusion (252) located in the recess, which protrusion (252) fits into the indentation (110) in the axle body (204), the clamping assembly comprising clamping straps and a sling plate (216) located on one side from the support arm (202) opposite the side where the axle pad (205) is located, the slider plate (216) having side portions (282) extending along the side of the support arm (202) towards the axle pad (205), and wherein the axle pad (205) has transverse lugs (251) which engage the side portions of the slider plate (116) to mutually lock the slider plate (116) and the axle pad (205) in a longitudinal direction of the carrying arm (202), and wherein the sling plate has at least one locking cam (290) and the carrying arm has at least one recess (291) which receives the locking cam (290) from the sling plate (216) in order to align the sling plate (216) with respect to the carrying arm (202) secure in the longitudinal direction of the support arm (202). 25

A vehicle such as a trailer or a truck, which comprises a wheel axle suspension according to any one of the preceding claims.