GB1561263A - Axle mounting arrangement for a trailer vehicle - Google Patents

Description

(54) AXLE MOUNTING ARRANGEMENT FOR A TRAILER VEHICLE (71) We, ALOIS KOBER K.G., a Germany Company, of Ichenhauser Strasse 14, 8871 Kötz 2, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to an axle mounting arrangement for a trailer vehicle either a single axle or two axles disposed close to one another in a tandem axle arrangement.

Most of the already known proposals for achieving, through the construction of the axle mounting of a trailer, enhanced reliability while travelling for a vehicle assembly comprising a tractor or towing vehicle and a trailer vehicle, derive from the following basis. With the trailer vehicle construction, due to sidewards wind forces or transverse accelerations, as by deviationary manoeuvres, becoming subjected to sideways inclination in its spring mounting, there then arise tie-rod forces at the trailer connection point which tend to jerk the tail end of the towing vehicle sidewards and so at least cause dangerous yawing articulation between movements of the whole towed arrangement.

In DTS 1 240 749 there has been disclosed for example an inclined link axle mounting with torsion bar springing and which has been designed in particular for caravans.

Through this it was intended to attain an improvement in the travelling behaviour so that rolling of the trailer is counteracted.

It is an object of the present invention further to improve the travel behaviour for a tractor-trailer arrangement with a single axle trailer or a trailer with a standem axle set-up.

In accordance with the present invention there is provided an axle mounting arrangement, for a trailer vehicle having either a single axle or two axles arranged in tandem, in which the or each axle is mounted on the trailer vehicle in a manner such that the height above ground of the instantaneous centre associated with the single axle or the height above ground of the instantaneous centre associated with the single axle or the height above ground of the instaneaneous centres associated, respectively, with the two axles, for sidewards inclination of the trailer vehicle, is substantially the same as the designated height above ground of the connection point provided on the trailer vehicle for connection to a towing vehicle.

The degree of equivalence between these heights is preferably to be to an extent such that the difference amounts to at most 100mm with the permitted maximum load on the trailer.

With the positional dimensioning of the instantaneous centre in accordance with the present invention the roll axis of the trailer becomes disposed parallel to or approximately parallel to, the travel track through the trailer connection point. Thereby those sidewards force components, which arise from sideward movements when the instantaneous centre is disposed substantially higher or lower than the trailer connection point, become insignificant. The present traffic safety permitted speed limits for motor cars towing caravans and similar combinations can thereby be raised considerably without risk.

With a view to obtaining precision in travel behaviour for trailer with a tandem axle arrangement it can be advantageous for the instantaneous centres of the axles to be disposed at different heights. For such a case it is accordingly further proposed that the instantaneous centres of the two axles and the coupling means at the forward end of the trailer tow bar, when the tow bar is disposed with the coupling means at the designated height for connection to a towing vehicle, lie along a straight line.

Embodiments of the invention are hereinafter described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a plan view of an linkage for supporting a half axle; Figure 2 is a rear view of the half axle of Figure 1; Figure 3 is a rear view of a half axle mounted by a double transverse linkage; Figure 4 is a rear view of a rigid axle mounting with a "Panhard" rod; Figure 5 is a side view of part of a tractor-trailer combination having a single axle trailer; and Figure 6 a side view of part of a tractortrailer combination having a trailer with tandem axle arrangement; Figures 1 to 4 illustrate the graphical derivation of the instantaneous centre M for three known different axle mountings and in which through selection of specific construction parameters basically enable a desired height m of the instantaneous centre M to be obtained.

As shown in Figures 1 and 2 a swinging half axle 1 mounted by a triangular linkage 2 supporting a wheel intersects a vertical plane 3 passing through a wheel median plane at a pole P. A connecting line between the pile P with the base point of the wheel intersects with a vertical median plane 4 containing the longitudinal axis of the trailer at an instantaneous centre M.

In this way each triangular linkage is directed forwards from the wheel axle in the direction of travel F and the swinging half axle 1 encloses an angle with with a trans- verse vertical plane and an angle p with a horizontal plane so that the axle 1 slopes up from the triangular linkage to the vertical plane 4.

In accordance with Figure 3, the wheel axle is mounted by a double transverse linkage 5 having a Pole P at the intersection point of the projections of the axes of the transverse linkage 5. The instantaneous centre M is likewise the point of intersection of the rectilinear connecting line between the wheel base point with the pole P and the vertical plane 4 containing the longitudinal axis of the trailer. With the rigid axle construction in accordance with Figure 4, the instantaneous centre M is the point of intersection between the axis of the "Panhard" rod 6 and the vertical plane 4 containing the longitudinal axis of the trailer.

As shown in Figure 5 the height m of the instantaneous centre M is chosen to be the same for all axle constructions to correspond with the designated height for the trailer connection point A at which the tow bar 7 connects with the tractor or towing vehicle 8. In this way the roll axis 9 of the trailer is disposed accurately parallel to the path 10 of travel.

In Figure 6 the forward axle of the two axles of the trailer is, due to the existing weight distribution, somewhat more loaded than the rearward axle. So that the rear axle despite lesser springing may however take on equal toe-in and camber variations, it may be desirable for the instantaneous centre Mh of the rearward axle to be disposed somewhat higher than the instantaneous centre M, of the forward axle. The difference in height of the instantaneous centres is then so selected that both instantaneous centres together with the trailer connecting point A lie on a straight line 11 and which likewise again constitute the roll axis of the trailer.

WHAT WE CLAIM IS: 1. An axle mounting arrangement, for a trailer vehicle having either a single axle or two axles arranged in tandem, in which the or-each axle is mounted on the trailer vehicle in a manner such that the height above ground of the instantaneous centre associated with the single axle or the height above ground of the instantaneous centres associated, respectively, with the two axles, for sidewards inclination of the trailer vehicle, is substantially the same as the designated height above ground of the connection point provided on the trailer vehicle for connection to a towing vehicle.

2. An axle mounting arrangement, according to Claim 1, in which the difference, if any, between said height of the trailer connection point and said height of the instantaneous centre or centres, does not exceed mm when the trailer is loaded with its permitted load.

3. An axle mounting arrangement, for a trailer vehicle having two axles arranged in tandem, in which each axle is mounted on the trailer vehicle in a manner such that height above ground of the instantaneous centres associated, respectively, with the two axles, for sidewards inclination of the trailer vehicle and the height above ground of the coupling means at the forward end of the trailer vehicle tow bar, when the tow bar is disposed with the coupling means at the designated height for connection to a connection point on a towing vehicle, lie on a straight line.

4. An axle mounting arrangement for a trailer vehicle, substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. the designated height for connection to a towing vehicle, lie along a straight line. Embodiments of the invention are hereinafter described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a plan view of an linkage for supporting a half axle; Figure 2 is a rear view of the half axle of Figure 1; Figure 3 is a rear view of a half axle mounted by a double transverse linkage; Figure 4 is a rear view of a rigid axle mounting with a "Panhard" rod; Figure 5 is a side view of part of a tractor-trailer combination having a single axle trailer; and Figure 6 a side view of part of a tractortrailer combination having a trailer with tandem axle arrangement; Figures 1 to 4 illustrate the graphical derivation of the instantaneous centre M for three known different axle mountings and in which through selection of specific construction parameters basically enable a desired height m of the instantaneous centre M to be obtained. As shown in Figures 1 and 2 a swinging half axle 1 mounted by a triangular linkage 2 supporting a wheel intersects a vertical plane 3 passing through a wheel median plane at a pole P. A connecting line between the pile P with the base point of the wheel intersects with a vertical median plane 4 containing the longitudinal axis of the trailer at an instantaneous centre M. In this way each triangular linkage is directed forwards from the wheel axle in the direction of travel F and the swinging half axle 1 encloses an angle with with a trans- verse vertical plane and an angle p with a horizontal plane so that the axle 1 slopes up from the triangular linkage to the vertical plane 4. In accordance with Figure 3, the wheel axle is mounted by a double transverse linkage 5 having a Pole P at the intersection point of the projections of the axes of the transverse linkage 5. The instantaneous centre M is likewise the point of intersection of the rectilinear connecting line between the wheel base point with the pole P and the vertical plane 4 containing the longitudinal axis of the trailer. With the rigid axle construction in accordance with Figure 4, the instantaneous centre M is the point of intersection between the axis of the "Panhard" rod 6 and the vertical plane 4 containing the longitudinal axis of the trailer. As shown in Figure 5 the height m of the instantaneous centre M is chosen to be the same for all axle constructions to correspond with the designated height for the trailer connection point A at which the tow bar 7 connects with the tractor or towing vehicle 8. In this way the roll axis 9 of the trailer is disposed accurately parallel to the path 10 of travel. In Figure 6 the forward axle of the two axles of the trailer is, due to the existing weight distribution, somewhat more loaded than the rearward axle. So that the rear axle despite lesser springing may however take on equal toe-in and camber variations, it may be desirable for the instantaneous centre Mh of the rearward axle to be disposed somewhat higher than the instantaneous centre M, of the forward axle. The difference in height of the instantaneous centres is then so selected that both instantaneous centres together with the trailer connecting point A lie on a straight line 11 and which likewise again constitute the roll axis of the trailer. WHAT WE CLAIM IS:

1. An axle mounting arrangement, for a trailer vehicle having either a single axle or two axles arranged in tandem, in which the or-each axle is mounted on the trailer vehicle in a manner such that the height above ground of the instantaneous centre associated with the single axle or the height above ground of the instantaneous centres associated, respectively, with the two axles, for sidewards inclination of the trailer vehicle, is substantially the same as the designated height above ground of the connection point provided on the trailer vehicle for connection to a towing vehicle.

2. An axle mounting arrangement, according to Claim 1, in which the difference, if any, between said height of the trailer connection point and said height of the instantaneous centre or centres, does not exceed mm when the trailer is loaded with its permitted load.

3. An axle mounting arrangement, for a trailer vehicle having two axles arranged in tandem, in which each axle is mounted on the trailer vehicle in a manner such that height above ground of the instantaneous centres associated, respectively, with the two axles, for sidewards inclination of the trailer vehicle and the height above ground of the coupling means at the forward end of the trailer vehicle tow bar, when the tow bar is disposed with the coupling means at the designated height for connection to a connection point on a towing vehicle, lie on a straight line.

4. An axle mounting arrangement for a trailer vehicle, substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.