FR2737443A1 - Suspension for motor vehicle trailers and semi-trailers of commercial vehicles - has axle fixed to trailing or leading lower arms, with inclined shock absorbers as upper arms - Google Patents

Abstract

The "U" shaped mounting bracket has side pieces joined by a flat surface. The trailing arms are hinged on a pin passing through the lower bushes (6), and the shock absorber on the pin assembly (5). The ends of the trailing arms are bushed, allowing some twisting on the pins and the pins work in spherically contoured bushes running in shaped seats in the sides (11,12). The assembly is fixed to the trailer at the surface (13).

Description

 The invention relates to a suspension hand for an axle of an industrial vehicle in particular for an axle of a semi-trailer or road trailer, serving to provide the junction between the chassis of the vehicle, the link arm carrying the axle and the damper.

The suspension hands are generally produced in the form of a stamped or mechanically welded part having substantially the shape of a gusset or a stirrup with a section in
U, the sides of which are provided with bearing surfaces intended, respectively, for hooking the shock absorber and the link arm. Conventionally, the bearing surfaces are intended to receive pins, one supporting the eye of the shock absorber (the other end of which is fixed to the clevis of the axle), the other, the end of the arm of connection, clamped between the flange and counter-flange of the axle.

 The difficulty that is encountered in the suspension hands lies in the fact that the ranges, and in particular that receiving the axis of the shock absorber, are highly stressed during the loading operations of the semi-trailer, which generates very high mechanical and physical stresses such as to prematurely use the bores of said spans. We know that the static forces, especially when lifting the semi-trailer (alignment with a loading dock) can be several tonnes. These forces quickly erode the bores of the bearing surfaces of the suspending hands, and the play thus created can be the cause of masting and breaking of the axes.

 To overcome these drawbacks, it has been proposed to manufacture suspending hands ion from cut and stamped flanks assembled by mechanical welding, and to bring in pre-machined rings or ferrules in circular orifices and pre-bored that is fixed by an annular weld bead.

 This solution is not satisfactory because it is both expensive and mechanically unstable.

 Indeed, the welds are not always homogeneous and their mechanical strength, due to the constraints set out above, remains uncertain.

 In addition, and although the rings have been previously bored, we are often forced to rectify them again, after assembly on the hand with suspens ion, because of the thermal expansions linked to the welding and the deformation of the metal they train. However, this operation is made difficult by the fact that the flanks are not strictly perpendicular to the axis of the spans, which causes, in the absence of a reference plane, serious difficulties of centering, of dimension, which harms machining precision.

 The object of the invention is to remedy these drawbacks and to propose for this purpose a suspension hand in which any welding operation on the bearing surfaces is deliberately excluded.

 The object of the invention is achieved by a suspension hand for an axle of an industrial vehicle, in particular for an axle of a semi-trailer or road trailer consisting of a stamped or mechanically welded metal part having substantially the shape a U-shaped stirrup, the open face of which is intended to be turned towards the axle, the lateral flanks of the suspension hand being provided with a first bearing intended to support an axis used for the attachment of a shock absorber and a second bearing intended to fix one end of a link arm.

 In accordance with the invention, the lateral flanks of the suspension hand comprise, in line with the first bearing, two hemispherical punctures directed towards the inside of the hand, facing each other, these punctures comprising a formed seat a spherical crown for receiving bearings supporting the axis of attachment of the shock absorber, these comprising at least one contact zone sliding on the corresponding seats of the punctures.

 Advantageously, the punctures made on the sides of the suspension hand are produced by stamping.

 When the shock absorber is mounted on the suspension hand, the bearings are held in abutment on their respective seats by the axis of the shock absorber, the axis being supported at one of its ends, and fixed at the other end, which is threaded, on the sides of the suspension hand with a nut.

 To ensure that the end of the shock absorber is held at an equal distance from the two cheeks of the suspension hand, two washers can be inserted, one on each side, between the eye of the shock absorber and the two sides lateral.

 The design of the fixing of the axle connecting one end of the shock absorber to the suspension hand, has mainly the following advantages: first, the punctures represent a larger and better formed surface than that of the suspension hands used until now receiving the pivoting forces and centering the axis which establishes the connection between the suspension hand and the shock absorber. This results in a reduction in the wear of these surfaces by a better distribution of the forces on the edges of the punctures, as well as a better concentration of the forces on the pivot axes and an equal distribution between the two sides of the hand. of suspense ion. Finally, the design of the invention gives more freedom of movement to the shock absorber, thanks to a more uniform loading of the elastic part of the mounting eye of the shock absorber.

During mounting, the mounting pins can be introduced into the suspension hand either on one side or the other.

 According to a preferred embodiment of the invention, the second reach of the suspension hand intended for the reception of the link arm is formed by two bearings, force fitted into two calibrated beaten collars, directed towards the outside of the hand , opposite one of the other.

 As a variant, the second bearing surface of the suspension hand can be formed of a ring attached by crimping on the periphery of a circular orifice cut out in each of the two sides of the suspension hand. The insert ring is pre-machined and has an annular shoulder punctually forming claws, after crimping on the side of the suspension hand.

 The design of the second litter essentially meets the same criteria as the design of the first litter. Thus, whether the bearings are press fitted into the threshed collars or whether they are added bosses, fixed by crimping in an orifice cut in each lateral flank, in both cases, an enlarged surface is obtained. intended to receive the pivoting forces to which the link between the suspension hand and the link arm is subjected. This advantage can be further increased by giving the surface of the bearing or of the added boss, intended to be oriented towards the link arm, a domed shape.

 Finally, both the design of the first span and that of the second span offers the advantage, in the event of wear of the connection, of a faster and less expensive repair thanks to the possibility of replacing worn parts, or even broken.

 The object of the invention is also achieved by an industrial vehicle provided with a suspension hand for an axle, as described so far.

 The suspension hand according to the invention is intended to be attached to the chassis, in general to a spar, of the semi-trailer or of the trailer by welding along the longest of the two sides adjacent to the core of the hand. suspension. For this purpose, the sides can be straight, that is to say each side can extend in a single plane. Alternatively, and more advantageously, the lateral flanks can be deflected at their free ends, so that the free ends of the sides are slightly bent towards the inside of the suspension hand. This has the advantage that the weld bead placed outside around the suspension hand does not end at the edge of the chassis beam and is thus much less exposed to the risk of tearing. This effect can be further improved by extending the weld bead around the free ends of the bent sides towards the inside of the suspension hand.

Other characteristics and advantages of the invention will emerge from the description below and the attached drawings in which:
Figure 1 is a perspective view illustrating the technical environment of a known suspension hand, and in particular its coupling with the link arm, the damper and the flange and counter-flange of the axle.

 Figure 2 is an elevational view of a suspension hand according to the invention.

 Figure 3 is a sectional view along line C-C of Figure 2.

 Figure 4 is a sectional view of the hanger along section A-A of Figure 2.

 Figure 5 illustrates the detail of a mounting variant of the first reach of the suspension hand.

 Figure 6 is a sectional view of the second span along line B-B in Figure 2.

 Figure 7 is a view of an alternative mounting of the second reach of the suspension hand.

 Figure 8 shows a specific case, under load, of the assembly of Figure 7.

 Figures 9 and 10 are views of a variant of the mounting of the second reach of the suspension hand.

 Figure 11 shows the principle of fixing the suspension hand to the chassis of a semi-trailer by welding.

 A suspension hand 1 illustrated in FIGS. 1 to 3 essentially consists of a metal piece in the shape of a stirrup having substantially the cross section of a U, the open face of which faces towards an axle 2.

 Hand 1, seen in section, has two lateral flanks 11 and 12, each of trapezoidal shape having three straight sides 16, 17 and 18 and an oblique side 19. The largest side 16 of the three straight sides of the two sides are connected by a core 13.

Alternatively, the acute angle formed between the sides 17 and 19 can be cut along a line 170 shown on the
Figure 2 in dotted lines, giving the sides of the suspension hand the shape shown in Figure 1.

 Preferably, the core 13 of the stirrup (Figure 5) is of substantially convex shape to avoid the localization or the concentration of mechanical and physical stresses at a determined point of the suspension hand.

 In the narrower part oriented towards the side 18, the flanks 11 and 12 are formed so as to each have a cheek 14 or 15, the distance between the cheeks 14 and 15 being greater than that between the flanks 11 and 12 in their widest part, that is to say on the 17 side.

 The non-deformability of the suspension hand 1 can be increased by placing, if necessary, one or two additional spacers 82, 83 inside the suspension hand without, of course, hindering the passage of the damper 3 or of the arm. link 4 (see Figure 11).

 On the flanks 11, 12 of the U of the suspension hand, there are bosses or bearing surfaces 5 and 6 of which the first bearing 5 is reserved for the attachment of the shock absorber 3 by a first eye 30 and whose second bearing 6 is reserved for fixing the link arm 4. The damper 3 has its other eye 31 fixed on the upper axle-carrier flange, the link arm being sandwiched between this flange 7 and a counter-flange 8, those -this serving as a bearing for the axle 2 held by stirrups 9 fixed by nuts 10 under the counter-flange 8.

 According to the invention, as shown in particular in Figure 4, the bearing 5 intended to receive the eye 30 of the shock absorber 3 has the particularity of being made up of two punctures 51 produced by stamping in the sides 11 and 12. These punctured are directed towards the inside of the U of the stirrup and comprise a hemispherical crown 52 constituting an articulated and self-centering seat for the bearing 53 which supports the axis 54 carrying the eye 30 of the shock absorber 3. The bearings 53 also have a partly hemispherical shape so as to have at least one annular zone 55 of sliding contact. The term "sliding contact" means the fact that the bearing 53 can move relative to its seat formed by the punctures 51, in the manner of a ball joint, under the stresses generated by the oscillations of the shock absorber. contact between these bearings and these parts move infinitesimal and thus absorb the oscillations generated by the eye of the shock absorber without there being any relative movement between the axis 54 shock absorber support and the bearings 53. in other words, the axis 54 and the bearings 53 constitute an integral and stable unit and the oscillations are absorbed by the relative play of the bearings on the partially spherical seats of the punctures 51.

 Each flank 11, 12 has a flat 51 and an associated bearing 53, the bearings being machined, bored as close as possible to the tolerance of the axis to limit the phenomenon of masting of the axis 54. The axis 54, shouldered one of its ends, passes through the two bearings 53 and the eye 30 of the shock absorber 3 and is fixed, at the other threaded end, by a nut 56. This assembly avoids any premature or untimely wear of the reserved range to the attachment of the shock absorber due to the relative clearance between the bearings 53 supporting the axis of the shock absorber, and their seat 51.

 In addition, the absence of welding or machining after assembly makes it possible to reduce production costs very significantly while significantly increasing the mechanical and physical resistance of the suspension hand.

 Figure 5 shows in detail the mounting of the first bearing 5. More particularly, we see in this Figure that, in addition to the elements described so far and shown in particular in Figure 4, two washers 58 arranged on the axis 54 of one side and the other of the eye 30 of the shock absorber 3, interposed between the eye 30 and each of the two lateral flanks 11 and 12. The thickness of these washers 58 is chosen so that the eye 30 retains sufficient freedom of movement between the two lateral flanks 11 and 12, but that its position nevertheless remains as much as possible centered between the two lateral flanks. In other words, the thickness of the washers 58 is chosen in such a way that the movement in the axial direction of the axis 54 of the eye 30 is reduced to a minimum possible, while keeping the damper 3 sufficient freedom of movement around, and relative to its longitudinal axis thanks to an element elastic 32 inside laughing eye 30.

The second bearing is intended for fixing a link arm to the suspension hand. This second scope is represented in the drawings in two different variants. The first variant, referenced 70, is shown on the
Figure 6 in a principle version and in Figures 7 and 8 in a version according to the preferred embodiment of the invention. The second version of the second litter is referenced 6 and shown in Figures 9 and 10.

 The second bearing 70 consists of two collars beaten in the flanks 11 and 12 facing outwards and executed perpendicularly to them, on the one hand, and two machined and bored bearings 71, force-fitted into the beaten collars , on the other hand. The bearings 71 essentially consist of a part 72 in the form of a sleeve intended to be pressed into the tubular part of the threshed collar and of a part 73 in the form of a disc intended to marry the inner wall of the corresponding lateral flank 11 or 12 of the suspension hand 1. The dimensions of the bearing 71, and in particular the thickness of the disc part 73, are chosen in such a way that the link arm 4 retains sufficient freedom of movement inside the suspension hand 1.

 As a variant of this, and corresponding to the preferred embodiment of the invention, the bearings can be formed in such a way that the disc part 73 is curved towards the inside of the suspension hand 1. Such bearings, referenced 75, have the advantage that the freedom of movement of the link arm 4 in the direction of the axis 74 is essentially zero, but that the other movements of the link arm 4 remain possible.

 Furthermore, the bearings 71 or 75, depending on the variant chosen, are held on the lateral flanks of the suspension hand, and more precisely on the cheeks 14 and 15, by the axis 74 which passes through them. The axis 74 is shouldered at one of its ends and threaded at the other in order to be fixed by means of a nut 76. Washers 77 are disposed respectively between the shoulder of the axis and the flank 15 and between the nut and the flank 14 ensuring good support of the axis mounted on the lateral flanks. This design ensures that the lateral flanks cooperate in this mounting of the link arm 4 instead of acting independently of one another.

 In general, the bearings 71 or 75 are force-fitted into the beaten collars. However, it may prove advantageous, for the sole purposes of mounting the link arm 4, to temporarily attach the bearings to the collars beaten by applying one or more points of glue, adhesive or solder. Often, one or two of these points are enough to attach the bearings without the lateral flanks or the bearings undergoing deformation.

 The variant of the second bearing, referenced 6, is produced in the form of a machined and bored ring 61, this being fixed by crimping on the two sides 11, 12 of the suspension hand. This ring has the distinction of having an annular shoulder 62 which will be folded down, during the crimping operation, on the edge of the circular orifice 63 in which the ring 61 has been engaged. The crimping of the shoulder 62 is punctually made to form claws 64 (FIG. 10) distributed uniformly over the periphery of the circular orifice 63. An annular stiffening ring 65 is produced, during the drawing of the sides, in the vicinity of the crimping zone of the bearing surface 6, in order to concentrate the physical and mechanical stresses linked to the crimping operation so as to avoid deformations detrimental to the alignment of the axes of the two rings 61 constituting the two bearing surfaces 6 of the suspension hand 1.

 The suspension hand, according to the invention, has multiple advantages, both from the economic point of view and from the mechanical resistance point of view due to the significant reduction in weld and especially the floating mounting of the shock absorber on its range 5 In addition, the bearing surfaces 5 and 70 (or 6) being produced from machined attached rings, and their mounting not causing modifications in the alignment of their axes, it is unnecessary to carry out post- machining after assembly.

 Figure 11 shows, schematically, a beam 81 of the chassis of a semi-trailer or trailer, below which is welded a suspension hand 1 according to the invention. The suspension hand 1 is reinforced by spacers 82 and 83. The lateral sides 11 and 12 are bent at their free ends, thus presenting bent parts 84 and 85.

 The suspension hand 1 is attached to the beam 81 by means of a weld bead 86 placed outside the suspension hand along the lateral flanks 11 and 12 and the core 13. This weld bead 86 is conduit, at the ends 84 and 85 of the sides 11 and 12 outside and inside the suspension hand. Thus, the weld bead surrounds the ends 84 and 85 so that the weld bead 86 ends on the contact surface between the beam 81 and the suspension hand 1.

 Finally, as illustrated in FIG. 1, the two suspension hands, left and right, can be joined by a cross-member 80 consisting of a reinforcement tube passing through the two sides of each suspension hand to absorb the forces.

 The reference signs inserted after the technical characteristics mentioned in the claims, have the sole purpose of facilitating the understanding of the latter, and in no way limit their scope.

Claims (13)

 1. Suspension hand (1) for an axle of an industrial vehicle in particular for an axle of a semi-trailer or road trailer, consisting of a stamped or mechanically welded metal part having substantially the shape of a stirrup in U having two lateral flanks (11, 12) connected by a core (13), the open face of the stirrup being intended to be turned towards the axle, the lateral flanks (11, 12) being provided with a first bearing (5) intended to support an axis (54) used for the attachment of a shock absorber (3), and of a second bearing (6) intended to fix one end of a link arm (4), characterized in what the lateral flanks (11, 12) comprise in line with the first bearing (5) two punctures (51) directed towards the inside of the hand (1) and facing each other, these punctures ( 51) comprising a seat formed by a hemispherical crown (52) and receiving bearings (53), supports of an axis (54) for hanging the shock absorber, these bearings comprising at least one annular zone (55), with sliding contact, on the corresponding seats of the punctures (51).  2. Suspension hand according to claim 1, characterized in that the punctures (51) are produced by stamping.  3. Suspension hand according to claim 1, characterized in that the bearings (53) are held in abutment on their respective seats (51) by the axis (54) of the damper (3), the axis (54 ) being supported at one of its ends and fixed at the other end, threaded, on the sides (11, 12) of the suspension hand by a nut (56).  4. Suspension hand according to one of claims 1 to 3, characterized in that the second bearing (70) consists of two collars beaten in the sides (11, 12), facing outwards and two machined bearings and bored (71) press fitted into the beaten collars.  5. Suspension hand according to one of claims 1 to 3, characterized in that the second bearing (6) is formed of an attached ring (61), fixed by crimping on the periphery of a circular orifice (63) cut in each side flank.  6. Suspension hand according to claim 5, characterized in that the added ring (61) is machined and has an annular shoulder (62) punctually forming claws after crimping on the sides (11, 12).  7. Suspension hand according to claim 5 or 6, characterized in that the added ring (61) is bored before crimping.  8. Suspension hand according to one of claims 1 to 7, characterized in that the interval of the sides (11, 12) in the vicinity of the first span (5) is less than that of the sides in the vicinity of the second span (6).  9. suspension hand according to claim 5, characterized in that the sides (11, 12) have a stiffening rod (65), obtained by stamping, the latter surrounding the area of the fitted rings (61) to concentrate the stresses mechanical and physical due to the crimping operation.  10. Suspension hand according to any one of claims 1 to 9, characterized in that the core (13) of the stirrup is of substantially convex shape.  11. Suspension hand according to any one of claims 1 to 10, characterized in that the free edges (84, 85) of the cheeks (11, 12) are oriented towards the inside of the hand, at least in the vicinity of the edge (17) intended to be welded to the chassis of the vehicle.  12. Industrial vehicle comprising a chassis and an axle (2) mounted on two link arms (4) spaced from each other and connected to the chassis by two suspension hands (1), these suspension hands ( 1) being intended to also serve for the attachment of a shock absorber (3), characterized in that each suspension hand (1) conforms to one of claims 1 to 11.  13. Vehicle according to claim 12 in combination with claim 11, characterized in that the hand is fixed to the chassis by a welding bead (86), the bead (86) surrounding the two free ends (84, 85) at least sidewalls (11, 12) in the inward-facing part of the hand (1).