DE10230912B4 - security element - Google Patents

Abstract

Safety element (5) for the tow bar of a single or multi-lane trailer (12) for a single-track towing vehicle (13),
With
- A first torsion part (1) and
A second torsion part (2),
which are rotatable relative to each other about a torsion axis (100) having a directional component in the longitudinal direction (10) of the trailer (12),
characterized in that
- One of these torsion parts (1 or 2) with a rotatably mounted, circumferentially changing Torsionskontur (101a) is provided, and on this Torsionskontur (101a) is applied a contour key which is non-rotatably connected to the other torsion part (2 or 1);
- Both torsion parts (1, 2) for taking a mutual rest position with respect to the torsion axis (100) are biased; and
- When deflection from this rest position with the deflection increasing restoring force (RK) occurs, which seeks to move the two torsion parts (1, 2) in a direction to take again the mutual rest position.

Description

I. Field of application

The The present invention relates to a security element with which the Towing drawbar of a or multi-lane trailer can be attached to a single-track towing vehicle. Farther the invention relates to a trailer, which is equipped with such a security element. As a towing vehicle comes in particular a bicycle into consideration.

II. Technical background

Provided is attached to a single-track towing vehicle a likewise single-track trailer, is a twist of the trailer relative to the towing vehicle about a horizontally longitudinal axis not necessary, but it is generally used for cornering only a steering joint with a steering axis that is vertical or at least a vertical component provided.

• – entweder bei Schrägstellung des Zugfahrzeuges, z. B. aufgrund Kurvenfahrt, den Anhänger hiervon unbeeinflusst horizontal zu belassen oder
• – bei vertikal stehendem Zugfahrzeug eine Schrägstellung des Anhängers in Querrichtung zuzulassen aufgrund eines von einem Rad des Anhängers überfahrenen Hindernisses, also einer Erhebung des Untergrundes.

On the other hand, if the trailer behind the single-track towing vehicle is multi-lane, a relative rotation about the horizontal longitudinal axis between trailer and towing vehicle must be possible in order to

• - either at inclination of the towing vehicle, z. B. due to cornering, leaving the trailer unaffected horizontally or
• - To allow a vertical position of the trailer in the transverse direction due to an overrun by a wheel of the trailer obstacle, ie a survey of the ground.

In both cases there is a risk that if excessive static or dynamic lateral forces occur pendant overturns, or - im Contrast this - at a trailer not overturning the trailer and overturning as a result of the relative twist between trailer and Towing vehicle damage on the towing vehicle, usually a bicycle, or the trailer occur.

The Document US-A-3 829 125 discloses a trailer for a bicycle. On the trailer frame is rigid a U-shaped Tiller attached, which ends approximately at the height of the bicycle seat. At this drawbar is rigidly an elongated positive guide piece made of elastic Plastic, for example LEXAN (registered trademark), whose tiller remote end as a U-shaped Fork is formed, which surrounds the perch of the bicycle. The perch is pivotally supported within this fork, so that the trailer drawbar um a substantially vertical axis, namely the perch longitudinal axis is held pivotally. A pivoting of the trailer drawbar around any other axis is largely excluded. That so trained and attached elastic forced guide piece exerts a slight bias on the towbar and pushes it down, because the perch typically under a small Angle is aligned to the vertical.

The Document US-A-4 721 320 relates to an attachment coupling for a bicycle for pulling a trailer. This trailer coupling has a mechanically stable and rigid fastener that on the bike at the angle between seat post strut and chain stay is determined. The connection between this fastener and the drawbar of the bicycle trailer over a flexible hose piece, held and held by the coils of a coil spring is protected.

The Document US-A-4 371 184 relates to a light trailer for a two-wheeler, for example a bicycle. The trailer has a pull rod whose free End is fixed against rotation in a piece of hose. In the other End of the hose piece engages a pin which is attached to a snap hook, which in turn be fixed to the perch of the bicycle can. The hose piece is flexible so far that there are different inclinations between Towing vehicle and trailer can compensate.

The document DE 298 15 913 U1 relates to a coupling for drives. A drive is provided with a drive motor and with a spindle provided with a feed nut, as well as with a coupling arranged between the two with a first coupling part cooperating with the drive motor and with a second coupling part cooperating with the spindle. Both coupling parts are provided with correspondingly formed, positively and non-positively co-operating front surfaces, wherein the first coupling part is axially displaceable on the output spindle of the drive motor against the force of an elastic member, and the second coupling part is secured on the co-operating with the nut spindle against axial displacement. In order to develop this coupling so that it can be used as overload protection for both directions without abruptly occurring torque changes, it is proposed that the front surfaces of both coupling parts are provided with one or two axially extending teeth with wedge-shaped cross-section, the flanks in engagement flat abut each other, and that the coupling formed by the two coupling elements by means of two bearing drive motor and spindle side is supported against the housing of the drive so that one of the coupling parts is axially displaceable.

The document DE 24 33 995 A1 relates to an overload clutch for limiting a transmitted torque. This overload clutch has two clutch plates, which have oppositely arranged, cooperating, undulating surfaces and are each mounted on a corresponding shaft. Furthermore, there is a force acting on one of the clutch plates compression spring which presses the surfaces against each other. If these two clutch plates are directly connected to the corresponding output or input shaft, differently applied axial pressures can cause different output torques. In the case of high torques, the corrugated surfaces of the clutch plates are oscillating from each other, causing shocks in the axial direction. To avoid this disadvantage, it is proposed that the loaded by the compression spring coupling plate relative to the shaft on which it is mounted, is axially displaceable. Furthermore, the opposing surfaces of the clutch plates may each have three or six substantially sinusoidal-like cam profiles, which increases the life of the clutch. As a result, even at the time of sliding, uniform torque transmission between the clutch plates occurs and the output torque remains unaffected by larger pressures.

As set forth above, it was already known, the connecting element between trailer drawbar or drawbar of a two-lane trailer and the single-lane access vehicle, in particular a bicycle made of torsionsfähigem, elastic material perform, about a mutual relative rotation between the two longitudinal planes to enable. The one for this proposed rubber or plastic materials may tire. In addition are the forces introduced by the material itself into the system are difficult determinable and, above all, not constant, solely due to its influence the ambient temperature and the aging of this material.

III. presentation the invention

From that Based on the object of the present invention, to create a security element of the type mentioned, which is a relative Torsion between the towing vehicle and the main part of the trailer allows, these relative torsion, however, independent is from the elastic properties of the security element material and their possible changes due to aging and / or environmental influences.

To Another object of the present invention is to provide a trailer be provided with such a security element.

• – eines dieser Torsionsteile mit einer drehfest angebrachten, sich in Umfangsrichtung verändernden Torsionskontur versehen ist, und an dieser Torsionskontur ein Konturtaster anliegt, der drehfest mit dem anderen Torsionsteil verbunden ist;
• – beide Torsionsteile zur Einnahme einer wechselseitigen Ruhelage bezüglich der Torsionsachse vorgespannt sind; und
• – bei Auslenkung aus dieser Ruhelage eine mit der Auslenkung zunehmende Rückstellkraft (RK) auftritt, welche die beiden Torsionsteile in einer Richtung zur erneuten Einnahme der wechselseitigen Ruhelage zu bewegen sucht.

Starting from a safety element for the trailer drawbar of a single or multi-lane trailer for a single-track tractor with a first torsion and a second torsion that are rotatable about a torsion relative to each other, having a directional component in the longitudinal direction of the trailer, the inventive Solution of the above problem, characterized in that

• - One of these torsion parts is provided with a rotationally fixed, changing in the circumferential direction Torsionskontur, and on this Torsionskontur a contour key is applied, which is rotatably connected to the other torsion part;
• - Both torsion parts are biased to assume a mutual rest position with respect to the torsion axis; and
• - Upon deflection from this rest position with the deflection increasing restoring force (RK) occurs, which seeks to move the two torsion parts in a direction to take again the mutual rest position.

Of the invention has trailer a drawbar which is rotatably connected to a towing vehicle, and this drawbar is on the trailer side over Security element with the above features rotatably with the rest of the trailer connected.

advantageous Refinements and developments of the invention will become apparent the dependent claims.

The Security element, which in the trailer and preferably between the trailer and his trailer drawbar, is arranged, comprises two relative to each other about the torsion axis, ie the horizontal direction, mutually rotatable torsion parts in a certain relative rotational position to each other, the so-called rest position, are biased.

Thereby, that when deflected from the rest position one with the deflection increasing Restoring force at least up to a certain maximum deflection or restoring force, occurs, which acts in the direction of taking the rest position, supports this Restoring force the taking of the rest position.

at straight standing bike, this restoring force acts a tip over of the trailer towards the side.

In an inclined position of the single-track towing vehicle, especially bicycle, z. B. due to cornering towards the curve inside and Nei tion of the trailer due to the centrifugal forces when cornering to the outside, the restoring force also counteracts a tipping of the trailer to the outside.

Thereby, that upon reaching a certain deflection or certain restoring force and crossing this limit deflection or limit restoring force the restoring force is lifted, becomes an overload the involved components and thus damage especially of the trailer or the connection between trailers and towing vehicle avoided.

After crossing The limit deflection can be the restoring force stay the same size So at the level of the maximum restoring force, or from this Level off again.

to Realizing this behavior, the first torsion part has one Torsionskontur, on which a contour key, the second torsion part is assigned, runs in the circumferential direction. The contour button can - in the Quiet - only rest against the torsion contour at a point or in a region of the circumference, However, the button preferably consists of a mating contour, ie a negative contour to Torsionskontur, and this mating contour is in the rest position flat on, but only selectively or regionally at a deflection or a few points or ranges of scope.

To For this purpose, the Torsionskontur at least one point the circumference, preferably at several, in particular two places, especially diametrically opposite, Make the circumference, elevations or depressions of which from sloping in both directions of the circumference oblique flanks.

While in the rest position over the counter contour the entire circumference is ideally applied to the torsion contour, these inclined surfaces slide the Torsionskontur and the counter contour on deflection from the rest position to each other off, so that off the rest position only a partial investment of Torsionskontur and counter contour takes place, and due to the wedge effect, the counter contour endeavors to return to the rest position in the torsion contour.

Both Elements are biased toward each other in the rest position.

The Contact plane between the two contours or Torsionskontur and On expiring button can be a lateral surface, so that then the bias must take place in the radial direction.

Preferably becomes the contact surface However, be a transverse to the axis of torsion surface, and the bias take place in the axial direction, which has the advantage that Torsionskontur and counter contour part of two annular, abutting one another Torsion parts are and in the rest position over the entire circumference together abut and especially one of the parts on the back of an axially resilient, in particular elastic, annular part over the can be applied to the entire scope with force, z. B. by means of a simple rubber ring or a disc spring package. This results a very simple and inexpensive Construction and minimizes the risk of jamming of the two torsion parts up to today.

at a Torsionskontur in the form of a lateral surface can then necessary Radial preload can only be applied by the radially inside or outside lying torsion part is radially biased in sections, and the individual sections relative to each other in the radial direction must be designed to be movable, what the constructive Effort in the amount drives.

In addition is at axial preload and annular, concentric around the Torsion axis arranged torsion parts and Torsionskonturen also the adjustment of the preload and their readjustment especially simply by screwing a support nut, on which itself the prestressed in the axial direction and thus also in the axial direction movable z. B. second torsion part is supported, which for the purpose of Anti-rotation in the surrounding housing z. B. by means of a multi-tooth profile guided axially movable is.

In a preferred embodiment the torsion contour has two elevations or depressions over the Scope distributed, especially diametrically opposite, on. In addition, must are set at which deflection angle from the rest position the maximum restoring force should be achieved.

If this, for example, at 90 ° relative rotation between trailers and towing vehicle, and then an opposite force, So not in the direction of rest, but in the direction of additional Deflection works, so can an over the circumference symmetrical formation of the torsion contour can be selected with two diametrically opposed elevations and offset by 90 ° Wells.

Should from the point of maximum restoring force the restoring force do not lose weight, but stay the same, so go from this point the torsion contour in a plane over what the reverse rotation the two torsion parts to each other into the area, in again a restoring force in the direction of rest position, relieved.

The The problems underlying the present invention then occur on when the multi-lane trailer over a Spreading in the horizontal, fork-shaped drawbar on single-track Towing vehicle attacks, z. B. at the spaced ends the axis of the rear wheel.

at a connection of the (even multi-lane) trailer via a single-armed drawbar on towing vehicle, z. B. at only one end of the rear wheel axle or centered on its seat post, can directly at the connection point z. B. via a ball joint a Torsionsmöglichkeit created around the longitudinal direction become.

For a stable Connection and therefore a stronger one durable trailer is however a bifurcated Drawbar indispensable, and then can the twistable security element only in the area between the connection point of the two drawbar arms and the rest of the trailer be arranged.

Preferably is in a housing, which close to or in the connection point of the two arms of the fork-shaped drawbar is formed, on the one hand housed the security element described above be, and on the other hand, the housing is already one of the two Joint parts of an additional Steering joint whose steering axis has a vertical component or the vertical is to make a turn between towing vehicle and pendant to enable.

Preferably the steering joint is likewise cable-shaped on the side of one joint part, preferably on the side passing through the housing of the Security element is formed against tipping of the trailer.

The Safety element and preferably also the steering joint are thus central, so in the transverse direction centered and not offset to the side, in the trailer ordered. This provides the extra Advantage that in such a central strut, in front of or behind the Steering joint - preferably behind it in the direction of travel and also integrated into the housing of the safety element - a overrun brake can be accommodated.

c) embodiments

A embodiment according to the invention in the following with reference to the figures described in more detail by way of example. Show it:

1 : a perspective principle representation of the trailer,

2 a longitudinal section through the security element and

3 a partial section through some components of the security element,

4 : a development of the torsion contour and

5 : A cross-sectional view of another design of the security element.

1a shows a perspective view of the trailer 12 , the main part only by the extension of the base tube 6 and the two adjacent wheels is indicated while the drawbar 12a with the security element 5 the trailer is realistic.

Here is the trailer 12 with his drawbar 12a at the rear wheel 13a a single-track towing vehicle, usually a bicycle, coupled by the forked drawbar 12a with their arms lying next to each other at the front 14a , B at the two laterally outwardly projecting ends of the axle 13a of the rear wheel 13 is attached. The firmly connected arms 14a , b and thus the entire drawbar 12a can be around this transverse axis 13a ' move, and may also have a slight play in the longitudinal direction of this transverse axis 13a ' However, beyond this axis there is no possibility of movement.

When cornering a steering angle of the trailer 12 relative to the longitudinal direction of the towing vehicle is at the point of connection of the arms 14a , b, just behind the end of the rear wheel 13a of the towing vehicle, in the drawbar 12a a steering joint 20 with a vertical steering axle 200 built-in.

For this purpose, at the rear, connecting end of the fork-shaped drawbar a vertical pipe section 15 welded, which pivots about the approximately vertical steering axis 200 in a fork-shaped design of the housing 8th is stored, whose ends are therefore vertically spaced one above the other.

The housing 8th is part of the security element 5 , which is a relative rotation of the rest of the trailer 12 around the approximately horizontal axis of torsion 100 relative to the housing 8th of the security element 5 allows, which together with the drawbar 12a rotationally fixed with respect to the horizontal longitudinal axis is connected to the towing vehicle.

Part of this remaining trailer 12 is also the central tube 6 , which here as a square pipe is executed and partly naturalistic, from the housing 8th outstanding, is shown, and in the housing 8th longitudinally fixed, but rotatable about the torsion axis 100 , is stored, as based on the detailed representations of 2 and 3 explains:

2 shows a longitudinal section through the fully assembled security element 5 , while 3 in the partial longitudinal section only the housing 8th shows, in which only the first torsion part 1 and the rear threaded ring 3 are located.

Based on 3 it can be seen that the torsion part 1 in the case 8th by means of a multi-tooth profile 7 longitudinal 10 , ie along the torsion axis 100 , is slidable, opposite the case 8th however due to the splined profile 7 is not rotatable.

This torsion part 1 is annular and - like all functional parts of the security element 5 apart from the case 8th - concentric to the torsion axis 100 arranged and constructed so that through the central opening, the in 2 recognizable base tube 6 of the trailer 12 can extend through.

3 shows further that the left, so forward, facing, annular end face of the first torsion part 1 does not represent a plane but deviates from a torsion curve 101 with two forward, thus pointing to the left elevations at the highest and lowest point of the circumference and two opposite to the rear, ie in the 3 , right-recessed pits on the left and right sides of the circumference.

The rear screw ring 3 is from behind, so from the right, with an external thread in a corresponding internal thread of the housing 8th screwed in, and serves to support this first torsion part 1 to the rear, but not directly, but via a rubber ring in between 9 who in 2 is shown. rubber ring 9 and rear threaded ring 3 also have a central passage opening in the direction of the torsion axis 100 for the passage of the base tube 6 on.

As 2 can recognize, is due to this forward torsion contour 101 of the first torsion part 1 a second, also annular torsion part 2 with its rear-facing counter-contour 102 on which the negative form to Torsionskontur 101 has, and in a certain rotational position, the rest position (in which no relative rotation between the first and second torsion part 1 . 2 present) abut each other, as the settlement of the upper half of the circumference of the 4a shows.

The second torsion part 2 Leans forward, so in 2 to the left, in the longitudinal direction against a front stop ring 16 from, the longitudinally fixed and rotationally fixed to the housing 8th connected is.

This second torsion part 2 is torsionally and longitudinally fixed to the base tube 6 the trailer, preferably a non-circular tube, z. B. a square tube, connected, which extends through the first torsion part 1 , the rubber ring 9 and the rear threaded ring 3 as well as the back of the case 8th screwed annular sleeve 8a extends to the rear and firmly, so especially rotationally, but also longitudinally, with the rest of the trailer 12 connected is.

A relative rotation of the rest of the trailer relative to the housing 8th thus means a relative rotation of this base tube 6 around the torsion axis 100 and thus also the second torsion part 2 relative to the housing 8th , and thus also relative to the first torsion part 1 as well as this second torsion part 2 supporting front stop ring 16 , and therefore between stop ring 16 and second torsion part 2 a sliding washer 4 z. B. from a good sliding plastic, something Teflon is arranged.

Also from the towing vehicle 13 on the trailer 12a To be transmitted tensile forces are thus from the housing 8th over rear threaded ring 3 , Rubber ring 9 , first torsion part 1 and second torsion part 2 in the base tube 6 and with it the rest of the trailer 12 initiated.

The housing 8th is forward against contamination by means of a lid 11 locked.

With relative rotation of the torsion parts 1 and 2 against each other about the torsion axis 100 slides - as in the settlement of the 4b shown - the longitudinally oriented elevation of a torsion part, z. B. 1 , on the out of the depression of the torsion part 2 leading edge of the mating contour z. B. 102 off, causing the two torsion parts 1 and 2 Forcibly be forced apart in the axial direction.

Due to the unchangeable distance between the rear threaded ring 3 and front stop ring 16 this causes an axial compression of the rubber ring 9 , And thus increasing with increasing deflection axial preload force VK on the first torsion part 1 , which due to the torsion axis 100 inclined contact surface of the two contours 101 . 102 causes a force acting in the direction of the rest position restoring force RK against each other.

The prerequisite for this is that preferably both contours 101 . 102 and preferably without kinking from their elevations to their depressions and vice versa, and good lubricious materials for the particular torsional contours of the torsion parts 1 . 2 to get voted.

As 4b Furthermore, the magnitude of the restoring force RK decreases with increasing axial pressure of the rubber ring 9 to, until the second torsion part 2 the vertex of the torsion contour 101 has reached or vice versa. When this point is exceeded, the maximum restoring force Rk _max. can the contour, z. B. the counter contour 102 , straight, so with a constant axial distance to the front of the second torsion part 2 , run.

The result is that after exceeding a deflection at which already the maximum restoring force RK _max. is reached, this remains constant at the same level.

If the contour falls 102 By contrast, after this point RK _max. Again, this means at deflection beyond this point, not only that no restoring force acting in the direction of rest position is more, but on the contrary, a deflecting force AK acting in the direction of additional relative rotation occurs.

The first solution facilitates the resetting of the Relative rotation by hand, z. B. after tipping the trailer at upright bike.

The second solution makes manual reset difficult Although the deflection, favors but after crossing the maximum occurring in normal driving torsion completely overturned of the trailer or the bicycle and thus prevents occurring by the torsion damage on the bike or trailer.

The 5 show a solution in which the torsion contours 101 ' . 102 ' are formed as lateral surfaces and not as end faces.

In this case, for example, the second torsion part 2 ' a radially compressible body z. B. rubber with an elliptical or otherwise non-circular outer circumference (counter contour 102 ' ), which rotatably and longitudinally in turn with the central tube 6 , concentric in turn to the torsion axis 100 , connected is.

The first torsion part 1 has a negative-shaped elliptical or otherwise non-circular inner peripheral contour, in accordance with FIG 5 formed by having a hard part 1' with a round inner circumference on its inner circumference rolling rolls 17a , B distributed over the circumference, which is circumferentially through a cage 18 are interconnected, and distributed over the circumference have different diameters, according to the different gap width between the fixed part 1' with round inner diameter and the inner second torsion part 2 ' with non-circular outer diameter.

In the in 5a shown rest position, the rollers are also on the radially outwardly facing counter contour 102 ' of the second torsion part 2 ' at.

Upon rotation of the second torsion part 2 ' opposite the hard part 1 becomes the cage 18 with the rollers attached to it 17a , b, c ..., on the other hand, undergo half the relative rotation due to rolling of the rollers on both the outside and the inside of the rollers, and thereby the radially elastic second torsion part 2 radially from the rollers 17 at least on a part of its peripheral area pressed radially inward, whereby a restoring force RK in the direction of taking the rest position according to 5 arises, analogous to the previously described embodiment.

Likewise, the roles 17a , B, ..., however, also be mounted stationary, in which case it is also possible to dispense with a fixed part surrounding the rollers, which is then formed by the rollers themselves, only on their inner side on the rotatable torsion part 2 ' roll.

1

first torsion

2

second torsion

3

rear threaded ring

4

sliding disk

5

security element

6

basic pipe

7

Multi-tooth profile

8th

casing

8a

sleeve

9

rubber ring

10

longitudinal direction

11

cover

12

pendant

12a

shaft

13

towing vehicle

13a

rear wheel

13a '

axis

14a, b

poor

15

pipe section

16

front stop ring

17a, b

role

18

Cage

19

20

steering knuckle

100

torsion

101

Torsionskontur

102

mating contour

200

steering axle

Claims (26)

Security element ( 5 ) for the towbar of a single or multi-lane trailer ( 12 ) for a single-track towing vehicle ( 13 ), with - a first torsion part ( 1 ) and - a second torsion part ( 2 ) relative to each other about a torsion axis ( 100 ) are rotatable, the one direction component in the longitudinal direction ( 10 ) of the trailer ( 12 ), characterized in that - one of these torsion parts ( 1 or 2 ) with a rotationally attached, circumferentially changing torsional contour ( 101 ), and at this Torsionskontur ( 101 ) abuts a contour key, the rotation with the other torsion ( 2 or 1 ) connected is; - both torsion parts ( 1 . 2 ) for taking a mutual rest position with respect to the torsion axis ( 100 ) are biased; and - at deflection from this rest position with the deflection increasing restoring force (RK) occurs, which the two torsion parts ( 1 . 2 ) in a direction to re-taking the mutual rest position seeks to move. Security element according to claim 1, characterized in that that when crossing a limit deflection, the restoring force (RK) is canceled. Security element according to claim 2, characterized in that that after crossing the limit deflection instead of the restoring force (RK) an acting in the direction of increasing deflection force (AK) occurs. Security element according to one of the preceding claims, characterized in that on the Torsionskontur ( 101 ) At least the point of the rest position with the point of maximum restoring force (RK max.) Is connected by a uniform contour without paragraphs. Safety element according to one of the preceding claims, characterized in that the torsion contour ( 101 ) has a contour curve which generates beyond the point of reaching the maximum restoring force (RK max.) beyond a constant restoring force (RK) or generates such a deflection force (AK), the two torsion parts ( 1 . 2 ) is traced back to their mutual rest position. Safety element according to one of the preceding claims, characterized in that the torsion contour ( 101 ) along its circumference a different radius to the torsion axis ( 100 ) having; and the contour button in the direction of the torsion contour ( 101 ) is radially biased. Safety element according to one of claims 1 to 5, characterized in that the torsion contour ( 101 ) along its circumference different axial distances to a fixed point in the longitudinal direction ( 10 ) of the torsion axis ( 101 ) having. Security element according to claim 7, characterized in that the torsion contour ( 101 ) and / or the contour key is biased in the axial direction to the respective other element. Security element according to one of the preceding claims, characterized in that the contour button has a counter contour ( 102 ), which in the rest position over at least a part of the circumference, or over the entire circumference, on the torsion contour ( 101 ) is present. Security element according to claim 9, characterized in that the torsion contour ( 101 ) and the counter contour ( 102 ) in the rest position over the entire circumference at least two points, in particular at two opposite points with respect to the torsion axis ( 100 ) abut each other; and at least one of these contours ( 101 . 102 ) is axially biased by an annular, resilient member in the axial direction in the direction of the other contour. Safety element according to claim 10, characterized in that this annular, resilient member in the axial direction, a rubber ring ( 9 ). Safety element according to claim 10 or 11, characterized in that the prestressed contour ( 101 . 102 ) longitudinally displaceable, but rotationally fixed in the housing ( 8th ) is stored. Safety element according to claim 12, characterized in that the prestressed contour ( 101 . 102 ) via a splined profile ( 7 ) longitudinally displaceable, but rotationally fixed in the housing ( 8th ) is stored. Security element according to one of the preceding claims, characterized that the torsion contour ( 101 ) has along its circumference at least two recesses and at least two elevations, which are each arranged diametrically opposite one another. Safety element according to one of claims 1 to 13, characterized in that the torsion contour ( 101 ) along its circumference has three recesses and three increases located between these recesses, which are distributed uniformly over the circumference alternately follow one another. Safety element according to one of claims 1 to 13, characterized in that the torsion contour ( 101 ) has only one depression and / or elevation for determining the rest position. Pendant ( 12 ) with a drawbar ( 12a ), which is rotatably connected to a towing vehicle, and this drawbar ( 12a ) on the trailer side via a security element ( 5 ) rotatably with the remaining trailer ( 12 ), characterized in that - this security element is a first torsion part ( 1 ) and a second torsion part ( 2 ), and both torsion parts ( 1 and 2 ) relative to each other about a torsion axis ( 100 ) are rotatable, the one direction component in the longitudinal direction ( 10 ) of the trailer ( 12 ) Has; - one of these torsion parts ( 1 or 2 ) with a rotationally attached, circumferentially changing torsional contour ( 101 ), and at this Torsionskontur ( 101 ) abuts a contour key, the rotation with the other torsion ( 2 or 1 ) connected is; - both torsion parts ( 1 . 2 ) for taking a mutual rest position with respect to the torsion axis ( 100 ) are biased; and - at deflection from this rest position with the deflection increasing restoring force (RK) occurs, which the two torsion parts ( 1 . 2 ) in a direction to re-taking the mutual rest position seeks to move. Trailer according to claim 17, characterized in that the first torsion part ( 1 ) rotatably with the drawbar ( 12a ); and the second torsion part ( 2 ) rotatably with the remaining trailer ( 12 ) connected is. pendant according to claim 17, characterized in that the restoring force (RK) is adjustable. Trailer according to one of claims 17 to 19, characterized in that the drawbar ( 12a ) is fork-shaped and two horizontally spaced arms ( 14a , b) has; and every arm ( 14a , b) with its free end each at one end of the axle ( 13a ' ) of the rear wheel ( 13a ) of the towing vehicle ( 13 ) is attachable so that this drawbar ( 12a ) only around the axis ( 13a ' ) can be pivoted around. Trailer according to one of claims 17 to 20, characterized in that the drawbar ( 12a ) via a steering joint ( 20 ) with the security element ( 5 ) connected is; and the steering joint ( 20 ) a vertically oriented steering axle ( 200 ) Has. Trailer according to claim 21, characterized in that the steering joint ( 20 ) has a pivotable part, which is pivotally supported by a fixed bracket; this fixed steering joint mount integral with the housing ( 8th ) of the security element ( 5 ) is trained; and the pivotally supported steering articulated part bifurcated with the two horizontally spaced arms ( 20a1 . 20a2 ) is trained. Trailer according to one of claims 17 to 22, characterized in that the security element ( 5 ) in one, the trailer longitudinal direction ( 10 ) including the longitudinal median plane of the trailer ( 12 ) is arranged. Trailer according to claim 23, characterized in that the trailer ( 12 ) is formed symmetrically to this longitudinal center plane. Trailer according to one of claims 17 to 24, characterized in that in addition a trailer casserole brake is present, which between the drawbar ( 12a ) and the security element ( 5 ), or between the security element ( 5 ) and the rest of the trailer ( 12 ) is arranged. Trailer according to one of claims 17 to 25, characterized in that the trailer ( 12 ) is a two-track trailer.