WO1996003307A1

WO1996003307A1 - Suspension fork of a wheel bearing for two-wheeled vehicles

Info

Publication number: WO1996003307A1
Application number: PCT/EP1995/001707
Authority: WO
Inventors: Roman Ackeret; Andreas Osterwalder
Original assignee: MÜNCH, Martin
Priority date: 1994-04-30
Filing date: 1995-05-02
Publication date: 1996-02-08
Also published as: DE9407208U1; AU2525595A

Abstract

The invention provides a suspension fork (G) for the (front) wheel bearing of two-wheeled vehicles. The suspension fork (G) itself is rigid and can move toward the head tube axis (LKA) against spring force to provide suspension against bumps and jolts, and for that purpose is mounted for longitudinal movement with the aid of linear roller bearings (9) at the level of the head tube only. The linear bearing (9) can also make a compensatory pitching movement about a horizontal pitch axis (NA) and so is always aligned with the central axis of the fork (G) or the fork spar (2), thus substantially reducing friction between moving parts and avoiding any jamming or sticking during jouncing. A double joint (19, 20) with axes running perpendicular to each other (a pitch axis (NA) and a yaw axis (GA)) in the linkage between the linear roller bearing (9) of the suspension fork (G) and the vehicle frame (6) allows, in addition to the pitch movement and especially when there is a steering movement during jouncing, a second compensatory movement of the linear roller bearing (9) about the yaw axis (GA), which likewise counteracts jamming or sticking.

Description

description

Spring fork of a wheel bearing for two-wheel vehicles

The invention relates to a suspension fork for (front) wheel bearings on two-wheeled vehicles with two fork legs running on both sides of the wheel and parallel to one another, which are formed at their lower ends for receiving the wheel axle, rigidly with one another above the wheel and articulated above it on the one hand are connected to the vehicle frame and, on the other hand, to a steering device via a steering head.

Suspension forks on the front wheel suspension of two-wheeled vehicles, in addition to guiding the wheel, should absorb and dampen the bumps and shocks that occur while driving as evenly as possible.

Known suspension forks are predominantly designed as so-called telescopic forks. The fork legs each consist of a dip tube connected to the wheel bearing and a stand tube connected to the steering device, the stand tubes being able to dip telescopically into the dip tubes and this movement being damped by suitable means. By making this diving movement against a specific one

If the pretensioning force is carried out, the undesired diving or pitching movement of the vehicle, which is caused by the moment of inertia during a braking operation and is in this case counteracted.

Such a device is described in German utility model G 93 17 132.3. The lower and upper tubes are each rigidly connected to each other at their upper ends by a fork bridge. The vehicle driver is attached to the fork bridge of the stanchions and a ball joint is provided as a connection to the frame, on which - 2 -

To bridge the dip tubes, a trailing arm is also articulated by means of a ball joint, which is connected to the frame at its other end so as to be pivotable about an axis running perpendicular to the plane of the frame. Telescopic springs are arranged in the two immersion tubes, which act between the immersion and standpipes and dampen the immersion movement. In addition, a spring can be provided between the trailing arm and the frame, which dampens shocks and vibrations.

From DE-OS 37 08 580 a front suspension for motorcycles is known, which consists of a suspension fork with immersion and stanchion tubes that can also be moved into one another. A complicated double bearing of the head tube connected to the telescopic fork, without ball joints, enables not only a rotary movement of the fork about the steering axis, but also a pivoting movement of the fork in the vertical plane. This should take into account the change in position of the telescopic fork when deflecting and reduce the friction. The complicated design requires high expenditure on precision machine components as well as exact tolerances between them.

EP 0 507 088 describes a similar front wheel suspension of a motorcycle, which likewise consists of a telescopic fork with immersion and standpipes which are slidably guided into one another to absorb and damp the vibrations. For decoupling, i.e. In order to prevent the handlebars from swinging when the front wheel deflects, each standpipe in the upper triple tree is pivoted via a ball joint. This solution of tipping decoupling is very complex. The risk that the dip tubes and stanchions at the mutual guide points jam or even jam when deflected and steered is not eliminated.

Another proposal is to avoid a pitching movement of the steering device during braking or only to

REPLACEMENT LEAF reduce, the motorcycle handlebar decoupled from the diving movement of the telescopic fork by the pitching axis of the handlebar is offset from the diving axis by means of an angle joint. However, this poses an additional risk of tilting at the upper linear bearing point of the telescopic fork. Relatively high friction losses are also associated with this construction, as a result of which the suspension and damping are impaired.

In addition, to improve vibration damping, it was proposed to arrange a spring system within the telescopic tubes. According to another proposal, the spring system can also be attached to the outside of the vehicle frame and connected to the telescopic tubes.

DE-OS 36 23 567 discloses a front wheel suspension for motorcycles which has an articulated connection between the immersion tubes of the telescopic device immediately above the front wheel and the frame. The articulated connection consists of a rocking lever, the rotational movement of which counteracts a negative change in the caster; A shock absorber between the rocker arm and the frame dampens vibrations. This solution is intended to reduce vibrations and torsional forces.

US Pat. No. 5,209,319 describes a front wheel suspension for motorcycles, in which the telescopic area of the device is displaced upwards over the wheel. Only one main strut (or a fork leg) of the suspension extends from the steering device to the wheel bearing, the second strut running parallel to the steering device ends above the wheel, and only this area of the struts above the wheel is designed to be telescopic . With this construction, the goal was pursued to enable faster and more convenient wheel or tire changes. The missing spar on one side of the wheel makes the guidance of the wheel less secure and the suspension loses overall stability and rigidity, which is why a total of three rigid connections between the two struts or spars are required in the remaining area above the wheel. Furthermore, the path available for the telescopic movement of the parts of the struts which slide into one another is greatly shortened, which has a negative effect on the possible suspension and damping when driving over bumps or when braking.

All known telescopic suspension forks generally have the following disadvantages:

The standpipes and immersion tubes must be guided to one another at two linear bearing points, which, especially as soon as these bearing points are no longer exactly aligned, causes corresponding friction.

Since they have to take on three tasks at the same time, namely

- cushion and guide the wheel,

- enable the steering,

- transfer the braking forces,

these three tasks mutually influencing each other, they are exposed to high torsional and bending forces, which place particular stress on the linear bearing points between the standpipes and immersion tubes due to friction, which can even lead to the tubes becoming jammed at the bearing points. With each braking operation, high bending forces also act on the handlebar or steering head area due to the long lever arm. The caster of the wheel is reduced during the braking process, which reduces the track accuracy.

The object of the invention is to develop a new suspension fork for the front wheel suspension of a two-wheeled vehicle which can fulfill the above-mentioned tasks, but with good vibration compensation avoids high friction losses or even jamming of parts that are movable relative to one another and has a low weight. Compared to the conventional telescopic forks, the vehicle fork should be very torsion-resistant and should have a simple structure.

According to the invention, the object is achieved in that the inherently rigid suspension fork can be displaced parallel or in the direction of the steering head axis against the force of a spring support, in that it is mounted for longitudinal displacement only at the level of the steering head with the vehicle frame by means of linear roller bearings is

that in the articulated connection between the suspension fork and the vehicle frame the steering axis, about which the suspension fork can be pivoted, and a horizontal pitch axis, about which the linear roller bearing point of the suspension fork can be pivoted,

that a double-leg trailing arm is pivoted at one end about a horizontal axis on the vehicle frame and at the other end to the suspension fork and

that the spring support is arranged between the vehicle frame and the trailing arm or its connection point with the spring fork.

With this new type of front wheel suspension, the three tasks mentioned above are decoupled and performed by different parts; the mutual influence is thus eliminated or balanced.

The wheel is cushioned when it is raised when driving over bumps, for example, by the spring support arranged between the suspension fork and the vehicle frame

Suspension fork is simultaneously shifted in one linear bearing. Because the suspension fork is only at one height - 6th

is linearly guided and this linear bearing point can make a nodding compensating movement in its articulated connection with the vehicle frame, this linear bearing point is always aligned with the central axis of the suspension fork and there is no longer the risk of jamming or jamming; the friction during compression is also significantly reduced and the weight is reduced.

The steering of the vehicle is made possible by the articulated connection of the suspension fork to the vehicle frame and the braking forces are transmitted to the frame by the trailing arm, so that there is an anti-dive effect, i.e. the vehicle does not submerge when braking.

Another advantage is that the steering geometry remains constant in every driving situation, the caster of the front wheel is not reduced, the track accuracy is maintained. The steering head area is also only slightly loaded, an uneven deflection of the fork legs cannot occur.

According to a first embodiment of the invention, the suspension fork consists of two parallel fork legs, which are rigidly connected above the wheel by a lower fork bridge and axially displaceable at their ends in an upper fork bridge by means of linear roller bearings with reduced friction compared to slide bearings are led. The upper triple clamp can be connected to the vehicle frame by a ball joint and the lower triple clamp can be connected to the front end of a triangular trailing arm by a further ball joint.

In an improved embodiment of the invention, the upper fork bridge consists of the housings which accommodate the linear roller bearings and which are integrally connected to one another by a web part. The steering head tube rigidly connected to the steering rod of the steering device is at the front The end of the vehicle frame is pivotally mounted about the steering head axis by means of two roller bearings and a housing part enclosing the roller bearings can be pivoted about a horizontally extending pitch axis by means of a pitch joint and about a axis which runs perpendicular to the pitch axis by means of a yaw joint

Yaw axis pivotally mounted in the web part of the upper fork bridge.

Compared to the solution with the ball joint, the friction and the resulting wear are reduced, and the steering is less sluggish.

Through the two crossed joints, in the event that the steering is deflected in the compressed state of the suspension fork, a tilt decoupling for the steering device is achieved and, in turn, tilting is avoided.

Due to the possible yaw movement of the upper fork bridge relative to the steering head, tensioning of the suspension fork is avoided when deflecting during a steering lock.

The pitch axis and the yaw axis can intersect at different heights or ideally intersect at one point in the plane determined by the longitudinal axes of the fork legs. In the latter case, as long as the fork legs protrude beyond the pitch axis, no tilting moments can occur.

The pitch and yaw joint can be formed according to a possible embodiment of the invention by the

The web portion of the upper triple clamp has a rectangular recess in the center, in which an elongated shaped body, the lateral surface of which is flattened on one side, is rotatably held about the pitch axis by a pitch bolt and projects from the flattened side of the shaped body a pivot pin defining the yaw axis which can be rotated in a central bore of the housing part that closes the roller bearings u hold is. The latter can be done by a central screw connection.

The molded body preferably has a continuous longitudinal bore which is aligned with the connection bores leading out of the recess in the web portion of the upper fork bridge and into the housings of the linear roller bearings and into which the pitch bolt is inserted. During assembly, the pitch bolt can be inserted through a lateral, closable opening in the housing of the linear roller bearing.

According to one embodiment of the invention, the articulated connection of the triangular trailing arm to the suspension fork or its lower triple clamp lies on the steering axle.

In order to avoid a horizontal ball joint at the articulated connection point between the lower triple tree and the triangular trailing arm, which is subject to strong friction and therefore wear due to the axially acting forces, a bolt can be mounted in the lower triple tree by means of roller bearings be rotatably mounted about the steering axis, the upper bolt end being flattened such that it fits between cheeks formed at the front end of the triangular trailing arm, where it can be pivoted with the aid of a pin and locking ring.

In the case of the embodiment of the invention with a yaw axis, it may make sense to make the triangular trailing arm adjustable in length; this allows the wheelbase and caster of the front wheel to be adjusted. For this purpose, the end piece of the triangular trailing arm connected to the lower fork bridge can be formed in two parts, in that an inner part fits longitudinally slidably into a tubular, laterally slotted outer part. Tabs are then provided on the slot, on which the inner part and the outer part can be tightened in their mutual position by means of screws. According to another advantageous embodiment of the invention, the suspension fork consists of two fork legs running in parallel, which are rigidly connected to one another via the wheel; At the rigid connection point, a steering tube is attached in the center, which projects into a steering head tube which is rotatably mounted around the steering head axis at the front end of the vehicle frame and is longitudinally displaceable therein.

The upper part of the steering tube is preferably designed as a spline shaft and the associated spline shaft nut is pivotally mounted in the inner wall of the steering head tube about the horizontally extending pitch axis by means of bolts which are diametrically opposed to one another in its outer wall.

The steering head tube rigidly connected to the steering rod can be rotatably supported by means of grooved ball bearings in a frame head tube fastened at the front end of the vehicle frame in the direction of the steering head axis.

Preferably, the bolts carrying the spline nut are rotatably supported in two elongated holes which are provided opposite one another and parallel to the steering head axis in the wall of the steering head tube, so that the spline nut advantageously also, in addition to the pitching movement about the pitch axis defined by the bolts can execute the yaw movement directed perpendicular thereto. For this purpose, the bolts can be mounted in slot nuts, which in turn are each "floating" in a rubber cushion in the elongated holes of the steering head tube.

In this embodiment, the trailing arm can be mounted with one end rotatable about a horizontal axis on the diagonal rod of the vehicle frame and with its other end also rotatable about a horizontal axis on a bearing body in which the steering tube is in turn rotatably mounted . It can be connected to the upper, horizontal bar of the vehicle frame via the spring support his .

A coil spring, a plate spring assembly, a torsion spring, a rubber spring, an air suspension or a rod made of composite material can serve as spring support.

Further features and advantages of the invention result from the following description of three exemplary embodiments with reference to the attached drawings; show it

1 shows the front wheel of a two-wheeler with its suspension fork according to a first embodiment of the invention and the front part of the vehicle frame;

FIG. 2 shows the functional principle of the spring fork according to the invention as shown in FIG. 1 during compression;

3 shows the view of a section along the line BB in FIG. 1 through the lower fork bridge;

4 shows the view of a section along the line AA in FIG. 1 through the upper fork bridge;

5 shows the perspective illustration of a second embodiment of the suspension fork according to the invention for a two-wheeler together with the steering device and part of the vehicle frame;

Fig. The side view of the execution orm of Figure 5 with the front wheel.

7 shows an enlarged illustration of the connection point between the suspension fork, vehicle frame and steering device according to FIG. 6, partly in section; 8a shows a front view of the upper fork bridge of the suspension fork according to FIGS. 5 and 6 with the upper ends of the fork legs guided therein, the left half of the illustration being cut longitudinally;

8b shows a plan view of the fork bridge according to FIG. 8a, the left half in cross section;

9a the front articulation point of the (triangular longitudinal link on the lower fork bridge according to FIGS. 5 and 6 in front view;

9b the articulation point according to FIG. 9a in a side view, partly in longitudinal section;

10 shows the perspective illustration of a further embodiment of the suspension fork according to the invention;

FIG. 11 shows the side view of the illustration according to FIG. 10, where * in the steering head as a connection between the spring fork, steering device and vehicle frame is cut longitudinally;

12a shows the articulation point of the trailing arm on the suspension in accordance with FIGS. 10 and 11 in longitudinal section;

12b the articulation point according to FIG. 12a in cross section;

13a shows a cross section through the steering head of the embodiment according to FIGS. 10 and 11 according to line A-A in FIG. 11;

13b enlarges the view of the bearing in the steering head tube.

1, the rigid fork G is at the lower ends their fork legs 2 stored in the wheel bearing 1 of the front wheel of the vehicle. Above the front wheel there is a first (lower) fork bridge 3 for receiving the fork spars 2. This lower fork bridge 3 is articulated at its rear end via a ball joint 12 (see FIG. 3) to a triangular trailing arm 4. The rear ends of which are mounted on the diagonal frame rod 10 of the vehicle frame 6 so as to be rotatable about the horizontal axis WA. The triangular trailing arm 4 has a connection to the horizontal rod 13 of the vehicle frame 6 via a spring support FA attached to it. The upper ends of the fork spars 2 are guided by a second (upper) fork bridge 7 in a pair of linear roller bearings 9. This upper fork bridge 7 is rigidly connected to the steering rod 11 via a linkage 14 and articulated to the vehicle frame 6 via a ball joint 8. According to the invention, the fork G itself is mounted in only one pair of linear roller bearings 9, which enables the fork G to deflect with little friction, since the one pair of linear roller bearings 9 can always align with the upper fork bridge 7 in alignment with the fork legs 2 , whereby tilting or jamming of the bearings is avoided with certainty. The pivotability of the upper fork bridge 7 and the lower fork bridge 3 about the steering axis designated LA is made possible via the ball joint 8 or the ball joint 12, through which the fork bridges 3 and 7 are each connected to the vehicle frame 6. The forces acting on the front wheel are transmitted to the spring support FA via the lower fork bridge 3 and the triangular trailing arm 4 and are damped in cooperation with the bearing system in the upper fork bridge 7. The simple mounting of the fork G in the upper fork bridge 7 has a weight-saving effect. In addition, the fork is very torsionally rigid compared to the known telescopic forks and is nevertheless easy to carry out. This reduces the unsprung masses to a minimum and thus increases the response behavior of the spring system.

SPARE BLADE RULE 2 In Fig. 2 the principle of operation of the invention is shown with a side view; the different position of the individual components characterizes the unloaded (in strongly drawn lines) and the loaded condition (in weakly drawn lines) of the vehicle. Rl denotes the wheel position in the unloaded state, R2 denotes the wheel position in the loaded state.

FIG. 3 shows the section BB according to FIG. 1 through the lower fork bridge 3 in an enlarged view. The triangular trailing arm 4 is connected to the lower fork bridge 3 via the ball joint 12.

In Fig. 4 the section A - A through the upper fork bridge 7 is also shown enlarged. The upper fork bridge 7 is connected to the horizontal rod 13 of the vehicle frame 6 via the ball joint 8.

In the case of the front wheel suspension described above, the upper fork bridge 7, in which the two one-piece and rigid fork legs 2 are slidably mounted in their axial direction by means of the linear roller bearings 9, during compression due to the pivoting movement of the triangular trailing arm 4 about the axis WA participate in a pitching motion without restricting the turning steering movement. In order to allow this movement, in the first embodiment of the invention described above, the connection between the vehicle frame 6 and the upper fork bridge 7 was designed as a ball joint bearing 8, specifically with a lying ball head.

However, this ball-and-socket joint bearing 8 still has disadvantages, because as a plain bearing it is subject to quite a high level of friction and wear, and the steering acts relatively sluggishly because of the high sliding friction. In addition, forces which the driver, for example when driving uphill, introduces into the handlebar 11 rigidly connected to the upper fork bridge 7 when he tries to support himself for driving the legs with the Distance a between the steering axis LA and the point of application on the handlebar 11 a moment that is not absorbed by the ball joint bearing 8. Rather, these moments must be taken up by the linear roller bearings 9 between the fork legs 2 and their guides in the upper fork bridge 7, which in turn are supported on the fork legs 2, so that these bearing points are additionally burdened disadvantageously. Although the linear roller bearings 9 are preloaded during assembly, after some time in use there is a noticeable play due to wear. As a result of the surface pressure of the rolling elements on the fork legs 2, grooves can be clearly seen by running the rolling elements into the fork leg surface, although these have a surface hardness of 61 HRC measured by case hardening.

These disadvantages are avoided by a second, improved embodiment of the invention, as shown in FIGS. 5 to 9. The suspension fork G, as shown in FIG. 5 in a perspective view and in FIG. 6 in a side view together with a part of the vehicle frame 6, also consists of two one-piece, rigid fork legs 2, which are parallel to each other run and are formed at their lower ends for receiving the wheel bearing 1. The rigid connection of the two fork legs 2 above the front wheel of the vehicle by means of a lower fork bridge 3 still corresponds exactly to the first embodiment of the invention described above. With the lower triple clamp 3, the front end of the triangular trailing arm 4 is also articulated, the rear ends of which are pivotally mounted on the vehicle frame 6 about the horizontal axis WA. The upper ends of the fork legs 2 are guided in their axial direction in linear roller bearings 9, the housings of which are rigidly connected to an upper fork bridge 7. In contrast to the first embodiment, the handlebar 11 is not rigidly connected to the upper fork bridge 7, but via the linkage 14 to one Steering head tube 15 fastened, which projects into a bearing housing 16 provided at the front end of the vehicle frame 6, in which the upper fork bridge 7 is in turn pivoted about the horizontal pitch axis NA at the level of the linear roller bearings 9 (see also FIG. 7 in this regard) , 8a and 8b).

Since the spring support FA to the vehicle frame 6 is not arranged at its one end on the triangular trailing arm 4, but rather is articulated on the lower fork bridge 3, preferably together with the front end of the trailing arm 4, bending forces acting on the triangular trailing arm 4 are achieved avoided. A wide variety of spring elements can be used as the spring support FA, in addition to air suspension e.g. Depending on the position above or below the trailing arm, 4 helical compression or tension springs, torsion springs, rubber spring elements and plate spring assemblies or a rod made of composite material, for example made of carbon fiber reinforced plastic. In the latter case, it is possible to absorb high-frequency shocks by means of a corresponding fiber orientation, which is particularly advantageous in the case of road racing bicycles.

As can be seen from FIG. 7, the steering head tube 15 is rotatably mounted about its steering head axis LKA by means of two deep groove ball bearings 17. The inner rings of the deep groove ball bearing 17 are clamped together directly on the steering head tube 15, the outer rings are mounted in a sleeve 18 which is firmly connected to the vehicle frame 6. Outside the vehicle frame 6, the entire arrangement of the deep groove ball bearings 17 is coupled to the upper fork bridge 7 by a housing part 16. The deep groove ball bearings 17 significantly reduce the friction when steering, which, however, as described below, requires additional compensating movements, i.e. must be made possible.

The steering head axis LKA defined by the axis of rotation of the deep groove ball bearings 17 lies rigidly in the vehicle frame 6 and in the unloaded state of the suspension fork G, as has always been the case with the known arrangements of the completely rigid forks or the telescopic forks, coincides with the steering axis LA of the vehicle, which is to be regarded as the geometrical location around which all points of the suspension fork G rotate. When the suspension fork G is loaded, for example when the vehicle wheel is raised when driving over an unevenness and the fork struts 2 in the linear roller bearings 9 are axially displaced against a spring force, the front suspension fork G pushes through, for example through the ball-and-socket joint 12 defines the pivot point of the triangular trailing arm 4 through which the steering axis LA passes by a certain amount towards the fork legs 2. The consequence of this is that the steering head axis LKA and steering axis LA no longer coincide exactly, but the steering axis LA is inclined to the steering head axis LKA, even if only slightly. So that this angular deviation does not lead to jamming of the fork guide, the housing part 16 enclosing the deep groove ball bearings 17 is connected on the one hand by a pitch joint 19 to the upper fork bridge 7 in such a way that the aforementioned pitching movement in relation to the vehicle frame 6 on the other hand, a yaw joint 20, also arranged between the housing part 16 and the upper fork bridge 7, permits a yaw movement about a yaw axis GA which is perpendicular to the pitch axis NA. This is advantageous because when the steering rod 11 is turned in, the joint 19 that allows the pitching movement describes a circle around the steering head axis LKA and not around the steering axis, or the suspension fork G describes a cone about the steering axis LA and therefore the system would still jam when turning from stop to stop without this yaw movement. The yaw movement about the yaw axis GA thus allows the upper fork bridge 7 to be inclined when steering, so that jamming is avoided. The resulting yaw movement is minimal when the fork legs 2 run parallel to the steering axis LA; through a suitable choice of the axle offset between the steering axle LA and the one through the longitudinal * axis of the fork legs 2 certain level, this can be achieved.

It is particularly advantageous if the pitch axis NA of the pitch joint 19 and the yaw axis GA of the yaw joint 20 intersect in the plane determined by the longitudinal axes of the fork spars 2 on the central axis of the suspension fork G and the ends of the fork spars 2 extend beyond this intersection sufficient; then no tilting moments can arise around the pitch axis NA, which could increase the friction or even cause the linear roller bearings 9 on the fork legs 2 to tilt.

7, 8a and 8b show how the two joints 19 and 20, which transmit the steering moments from the steering rod 11 to the suspension fork G, can be designed according to the invention, for example.

The upper triple clamp 7 consists of the housings which hold the two linear roller bearings 9 and which are supported by a web part

21 are connected to a one-piece component, just the upper fork bridge 7. In the web part 21, a rectangular recess 22 is provided in the center and lying, from which connection bores 23 extend laterally into the housing of the linear roller bearings 9. An elongated shaped body 24, which has a continuous longitudinal bore and the lateral surface of which is flattened on one side, but can also be rounded, has a pivot pin 25 on the flattened side, with the aid of which the shaped body 24 is located halfway up the bearing housing part 16 Grooved ball bearing 17 is rotatably mounted on the side facing away from the vehicle frame 6 in a bore by a screw connection 26. The shaped body 24 is laterally inserted into the recess during assembly

22 pushed in the web part 21 of the upper fork bridge 7 until its continuous longitudinal bore is aligned with the connecting bores 23 in the web part 21, and is pivotally held there by a pitch bolt 27, which is located at

ATZBLATT REGEL2b) the assembly can be inserted through a lateral, closable opening 29 in the housing of the linear roller bearing 9. The pitch pin 27 determines the pitch axis NA mentioned above, the pivot pin 25 determines the yaw axis GA. An air gap 28 between the outer surface of the molded body 24 and the inner surface of the recess 22 enables the resultant, in principle very small pitching movement.

In order to be able to dispense with a lying ball joint 12 according to FIG. 3 also at the point of connection of the triangular trailing arm 4 with the lower fork bridge 3, this articulated connection, which involves a pitching movement and a steering movement, rigid with the fork legs 2 connected fork bridge 3 must be designed as shown in Fig. 9a and 9b.

In a continuous bore at the connection point of the lower fork bridge 3, a bolt 32 is rotatably mounted by means of roller bearings 30 and 31 and secured against falling out by means of stop 33 and lock nut 34. The center axis of this bolt 32 coincides with the steering axis LA of the vehicle. The end 35 of the bolt 32 which projects upwards beyond the stop 33 has a transverse, continuous bore and is laterally flattened to such an extent that it lies between the cheeks 36 and 37 of the correspondingly formed end of the common end, likewise provided with bores Leg of the triangular trailing arm 4 fits. A pin 38 which fits through the bores of the cheeks 36 and 37 and the flat bolt end 35 and can be secured by a locking ring 39 determines the axis of rotation DA for the spring movement of the trailing arm 4.

FIGS. 9a and 9b show yet another special feature according to the invention on the triangular trailing arm 4. The length of the trailing arm 4 can be adjustable, so that the wheelbase and the caster of the front wheel can be adjusted. This is the common one Leg of the triangular trailing arm 4 formed in two parts. An inner part 40 fits into a laterally slotted, sleeve-shaped outer part 41 and can be moved therein. On the outer part 41, tabs 42 are provided on both sides of the slot, on which the inner and outer parts 40 and 41 can be tightened and fixed in position relative to one another by means of screws 43. This length-adjustable longitudinal link makes sense in the case of the embodiments of the invention with a yaw axis; if no yaw movement is possible, a change in length of the trailing arm 4 could lead to jamming.

A further advantageous embodiment of the invention is shown in FIGS. 10 to 13. The perspective illustration of the suspension fork in FIG. 10 in turn shows two fork legs 2 running parallel, which are designed at their lower ends for receiving the front wheel axle 1 and above which (Not shown) wheel are rigidly connected, for example, by a fork bridge 3. However, as known from wheel forks on two-wheeled vehicles, the fork legs could also be attached directly to the steering tube 50. On the fork bridge 3 or another rigid connection between the fork legs 2, a further-extending steering tube 50 is rigidly attached in the center, which, as will be described in more detail below, is connected to a steering head tube 51 and the steering rod 11. The steering tube 50 is partially enclosed by a frame head tube 52 which is attached to the front end of the horizontal rod 13 of the vehicle frame 6 in the direction of the steering head axis LKA. A trailing arm 54 is articulated at one end above the fork bridge 3 on the steering tube 50 and at the other end on the diagonal rod 10 of the vehicle frame 6 so as to be pivotable in the vertical direction about the horizontal axis WA. In addition, the steering tube 50 is rotatable in the mounting of the trailing arm 54.

In the embodiment shown, the trailing arm 54 consists of two parallel legs 54a and 54b, which are pivotably mounted on pins arranged on the side of the steering tube 50 and on the diagonal frame rod 10. The double-articulated connection of the trailing arm 54a and 54b on the steering tube 50 is shown in more detail in FIG. 12a in longitudinal section and in FIG. 12b in cross section. Thereafter, the steering tube 50 is rotatably supported or guided in a bearing body 55 with the aid of a ball roller bearing 56. On the side of the bearing body 55, two diametrically opposite pins 53a and 53b are provided, on each of which the front ends of the trailing arm legs 54a and 54b are vertically pivoted via a roller bearing 57 and 58.

The trailing arm 54 also has a crossbar 59 to which one side of the spring support FA is attached, the other side of which is connected to the vehicle frame 6.

FIG. 11 shows the side view of the suspension fork according to FIG. 10, the steering head being cut longitudinally as a connection point between the suspension fork G, steering device and vehicle frame 6. FIG. 13 shows a cross section through this steering head along the line AA in FIG. 11 without frame head tube 52.

On the horizontal frame rod 8, the frame head tube 52 is attached at the front, inclined in the direction of the steering head axis LKA; in it, with the help of two deep groove ball bearings 62 and 63, the steering head tube 51, which is rigidly connected to the steering rod 11 via a linkage 14, is rotatably mounted about the steering head axis LKA. The steering tube 50, which is designed in its upper part as a spline shaft 50a and is mounted in a spline nut 60 in a manner known per se, projects into this steering head tube 51 on the steering head compartment LKA. Due to balls 61 running in the grooves or roller tracks of the precision ground spline shaft 50a and spline nut 60, the spline shaft 50a and the spline nut 60 can on the one hand

β AI other axially moved, on the other hand, torques can be transmitted.

In order to clarify the connection between the steering head tube 51 and the wedge nut 60, the steering head tube 51 is not shown entirely in section in FIG. 11, but is broken out below and above the connection point, so that the connection point can be seen in view ; in Fig. 13a the connection point is shown in cross-section, in Fig. 13b again enlarged in view. In two lateral, diametrically opposite and extending in the axial direction elongated holes 64 and 65 of the steering head tube 51 are preferably each in a rubber pad 66 and

67 the sliding blocks 68 and 69 virtually "floating". In the slot nuts 68 and 69, in turn, radially extending bolts 70 and 71 are mounted, which are also anchored in a recess in the lateral surface of the spline nut 60. Thus, on the one hand, the steering torque can be transmitted from the steering rod 11 via the steering head tube 51 to the steering tube 50 and thus to the suspension fork G leading the front wheel, on the other hand, when the front wheel is deflected, when the steering tube 50 or the spline shaft 50a moves axially against the force of the spring support FA and under rolling movements of the balls 61 in the spline nut 60, the spline nut 60 makes a compensating pitch movement about the horizontal pitch axis NA defined by the bolts 70 and 71 . In this situation, as already described above for the second embodiment of the invention, the steering axis LA and the steering head axis LKA no longer exactly match, but are slightly inclined to one another. In the event of a steering lock, this angular deviation is compensated for and jamming is avoided by using the sliding blocks which are "floating" in the axial direction

68 and 69 allow a minimal roll or yaw movement of the spring gear G and the spline nut 60 around the yaw axis GA running perpendicular to the pitch axis NA and the steering head axis LKA. Steering head axis LKA, pitch axis NA and yaw axis GA ideally intersect at one point, but can also intersect at different levels.

In the practical embodiment, the region of the steering head and especially the lower part of the spline shaft 50a can advantageously be protected against dirt by a bellows.

ATT HEGEL26

Claims

Expectations

1. suspension fork for the (front) wheel mounting on two-wheeled vehicles with two fork legs running parallel to each other on both sides of the wheel and parallel to one another, which are designed at their lower ends for receiving the wheel axle, rigidly with one another above the wheel and above that articulated with the Vehicle frame and on the other hand are connected to a steering device via a steering head,

characterized,

that the inherently rigid suspension fork (G) can be moved parallel to or in the direction of the steering head axis (LKA) against the force of a spring support (FA).

that it is mounted for longitudinal displacement only at the level of the steering head with the vehicle frame (6) by means of linear roller bearings (9; 60),

that in the articulated connection between the suspension fork (G) and vehicle frame (6) the steering axis (LA) about which the suspension fork (G) can be pivoted and a horizontal pitch axis (NA) around which the linear roller bearing parts (9; 60) the spring fork (G) is pivotable, run,

that a double-arm trailing arm (4; 54) is pivoted at one end about a horizontal axis (WA) on the vehicle frame (6) and at the other end it is articulated on the spring fork (G) and

that the spring support (FA) is arranged between the vehicle frame (6) and the trailing arm (4; 54) or its connection point with the suspension fork (G).

2. suspension fork according to claim 1, characterized in that the suspension fork (G) from two parallel

There are fork legs (2) which are rigidly connected above the wheel by a lower fork bridge (3) and are axially displaceably guided at their ends in an upper fork bridge (7) by means of linear roller bearings (9).

3. suspension fork according to claim 2, characterized in that the upper fork bridge (7) by a ball joint (8) with the vehicle frame (6) and the lower fork bridge (3) by a ball joint (12) with the front end of a triangular trailing arm (4) are connected.

4. suspension fork according to claim 2, characterized in that the upper fork bridge (7) consists of the linear roller bearing (9) receiving housings which are integrally connected by a web part (21) that the with Handlebar (11) of the steering device rigidly connected steering head tube (15) at the front end of the vehicle frame (6) by means of two roller bearings (17) around the steering head axis

(LKA) is pivotably mounted and that a housing part (16) enclosing the roller bearings (17) can be pivoted by a pitch joint (19) about a horizontally extending pitch axis (NA) and by a yaw joint (20) around a axis perpendicular to the pitch axis (NA ) extending yaw axis (GA) is pivotally mounted in the web part (21) of the upper fork bridge (7).

5. suspension fork according to claim 4, characterized in that the pitch axis (NA) and the yaw axis (GA) cross at different heights.

6. suspension fork according to claim 4, characterized in that the pitch axis (NA) and the yaw axis (GA) intersect at one point in the plane determined by the longitudinal axes of the fork legs (2).

7. suspension fork according to one of claims 4 to 6, characterized ge indicates that the web part (21) has a rectangular rectangular recess (22) in the middle, in which an elongated molded body (24), the lateral surface of which is flattened on one side, is rotatably held by a pitch bolt (27) about the pitch axis (NA) and that a pivot pin (25) defining the yaw axis (GA) protrudes from the flattened side of the shaped body (24) and which projects in a central bore of the Rolling bearing (17) enclosing housing part (16) is held rotatably.

8. suspension fork according to claim 7, characterized in that the pivot pin (25) of the shaped body (24) in the central bore of the housing part (16) is held by a centric screw connection (26).

9. suspension fork according to claim 7 or 8, characterized gekennzeich¬ net that the shaped body (24) with a through, from the recess (22) laterally into the housing of the linear roller bearing (9) leading connecting holes (23) aligned longitudinal bore , into which the pitch bolt (27) is inserted.

10. suspension fork according to claim 9, characterized in that the pitch bolt (27) during assembly through a lateral, closable opening (29) in the housing of the linear roller bearing (9) in the connecting bores (23) and the aligned longitudinal bore of the shaped body ( 24) is insertable.

11. Suspension fork according to one of the preceding claims, characterized in that the articulated connection point of the triangular trailing arm (4) with the suspension fork or its lower fork bridge (3) lies on the steering axle (LA).

12. suspension fork according to one of the preceding claims, da¬ characterized in that in the fork legs (2) rigidly connecting lower fork bridge (3) by means of roller bearings (30, 31) a bolt (32) is rotatably mounted about the steering axis (LA) and the upper bolt end (35) is flattened such that it is between the at the front end of the triangle - Trailing arm (4) formed cheeks (36, 37) fits and is held there rotatably with the aid of pin (38) and locking ring (39).

13. suspension fork according to one of claims 4 to 12, characterized in that the triangular trailing arm (4) is adjustable in length.

14. Suspension fork according to claim 13, characterized in that the end piece of the triangular trailing arm (4) connected to the lower fork bridge (3) is formed in two parts and an inner part (40) in a tubular, laterally slotted outer part ( 41) fits longitudinally, tabs (42) are provided on the slot, on which the inner part (40) and the outer part (41) can be tightened in their mutual position by means of screws (43).

15. suspension fork according to claim 1, characterized in that the suspension fork consists of two parallel fork spars (2) which are rigidly connected to one another via the wheel, that at the rigid connection point a steering tube (50) is attached in the center, which in a steering head tube (51) rotatably mounted at the front end of the vehicle frame (6) around the steering head axis (LKA) projects and is longitudinally displaceable therein.

16. Suspension fork according to claim 15, characterized in that the upper part of the steering tube (50) as a spline shaft

(50a) and that the associated spline nut (60) can be pivoted about a horizontal pitch axis (NA) in the inner wall of the steering head tube (51) by means of bolts (70, 71) embedded diametrically opposite one another in its outer wall is stored.

17. Suspension fork according to claim 15 or 16, characterized gekenn¬ characterized in that the steering rod (11) rigidly connected to the steering head tube (51) by means of deep groove ball bearings (62, 63) in a at the front end of the vehicle frame (6) in Rich direction of the steering head axis (LKA) frame head tube (52) is rotatably mounted.

18. Suspension fork according to one of claims 15 to 17, characterized in that in the wall of the steering head tube (51) opposite and parallel to the Lenkkopfach¬ se (LKA) two elongated holes (64, 65) are provided, in which the spline nut (60) bearing bolts (70, 71) are rotatably mounted.

19. suspension fork according to claim 18, characterized in that the spline nut (60) carrying bolts (70, 71) are rotatably mounted in slot nuts (68, 69), which in turn each in a rubber cushion (66, 67) floating in the elongated holes (64, 65) of the steering head tube (51) are mounted.

20. Suspension fork according to one of claims 15 to 19, characterized in that the trailing arm (54) with its one end rotatable about a horizontal axis (WA) on the diagonal rod (10) of the vehicle frame (6) and with its other End also rotatably about a horizontal axis on a bearing body (55) rotatable about the steering tube (50).

21. Suspension fork according to one of the preceding claims, characterized in that the (triangular) trailing arm (4, 54) is connected via the spring support (FA) to the upper, horizontal rod (13) of the vehicle frame (6) .

22. Suspension fork according to claim 21, characterized in that a coil spring is used as the spring support (FA).

23. Suspension fork according to claim 21, characterized in that a spring washer is used as the spring support (FA).

24. Suspension fork according to claim 21, characterized in that a torsion spring is used as the spring support (FA).

25. Suspension fork according to claim 21, characterized in that a rubber spring is used as the spring support (FA).

26. Suspension fork according to claim 21, characterized in that an air suspension is used as the spring support (FA).

27. Suspension fork according to claim 21, characterized in that a rod made of composite material is used as the spring support (FA).