SE507494C2 - Angle adjustment device for vehicle wheels - Google Patents

Abstract

Angle setting device for vehicle wheels which are journalled by a wheel shaft (33), which can be adjusted in different angles. The device comprises a first bearing unit (42), carried by an attachment, which unit is turnably journalled in the attachment around a first rotation axis (A) and which carries a second bearing unit (40), which is turnable in a second rotation axis (B), which deviates from the first said by a first angle ( alpha ). The second bearing unit (40) carries the wheel shaft (33) in a second angle ( beta ) between the rotation axis (C) and the second rotation axis (B). Hereby the wheel shaft (33) can be swung in different angles compared to the first rotation axis (A) in the attachment by turning the second bearing unit and simultaneous turning of the latter in the attachment (36).

Description

15 25 30 (N (fi). \] \ .F) _ “N k) therefore performs the control device of the vehicle with a number of angular deviations in relation to the“ normal angles ”such as those at the described, theoretical starting position. angles are the wheel inclination, the camber angle, compensate for the change in the wheel inclination that occurs in most spring systems during suspension, the spindle inclination, KPI, which must compensate for the fact that the spindle's axis of rotation must be placed within the center plane of the wheel. exaggerated to affect certain road properties, axle inclination, the caster angle which is the inclination of the spindle axle backwards or forwards and gives a force to return the wheels to steering straight ahead, tilting, "toe-in", is an alignment of the wheel axles, so that the wheels in neutral steering position are directed forwards - inwards relative to each other in order to compensate for the tendency to reverse oscillation which arises through the use of winches in the steering mechanism under the influence of force while driving. In addition, the steering link mechanism provides compensation for the inner wheel rolling along a circular arc with a smaller radius than the outer wheel, so that the cornering angle out ”gives each wheel a tangential position in relation to its rolling arc.

For minimum tire wear, it is desirable that each wheel is perpendicular to the road surface and parallel to the direction of rolling of the wheel, which when turning means tangential to the circular arc of the wheel for its rolling. The mentioned angles then aim to compensate iso? 494 b) imperfections in the steering mechanism and also for forces arising during travel, especially at high speeds.

Achieving compensation with fixed angles, however, gives optimal results only in certain ideal conditions, while in circumstances beyond that the compensation becomes deficient or can even counteract its purpose.

Mention may be made of conditions which occur with heavy and very low suspension, with heavy braking or acceleration, with uneven road surfaces and especially with off-road driving and with cornering at high speeds, with sloping carriageways and crosswinds.

In addition to the angular adjustment that is required for the steering wheels for the reasons mentioned, these vehicles also have adjustment of the wheel angles for other wheels.

Thus, it occurs that the wheel angles of the rear wheels change when cornering, which can provide improved road properties.

DISCLOSURE OF THE INVENTION: The object of the invention is to provide an angle adjustment device by means of which a compensating adjustment of the vehicle wheels can be achieved, which provides ideal wheel adjustment for low tire wear and best road properties in all conditions and circumstances, even extreme ones. To achieve this, it is required: - that the wheels are so suspended and stored that they can be adjusted at all angles within a certain angular range with a directly actuable mechanism, which has a sufficiently high strength against the forces that arise. in the vehicle; that a control means is provided, which controls the angle adjustment mechanism in such a way that the wheels, at the prevailing forces and rolling conditions, have an optimal angle adjustment with regard to road properties and tire wear.

How this is achieved according to the invention with a steering wheel of a vehicle is shown in the following description.

DESCRIPTION OF THE DRAWINGS: The accompanying drawings show a number of embodiments of the invention. In order to give a basic understanding of the mechanical and geometric principles used in the invention, a principled description is first given with reference to schematic figures.

Furthermore, an exemplary embodiment is given regarding a steering wheel for a vehicle.

In the drawings, Fig. 1 shows the angle adjustment mechanism schematically: Fig. 2 also shows the control means schematically; Fig. 3 shows an embodiment of the angle adjustment mechanism; and Fig. 4 shows the mechanism generally according to Fig. 3 but shown with certain details added. 10 15 20 25 30 01 CD _ \ J 494 DESCRIPTION OF PRINCIPLES AND PREFERRED EMBODIMENTS: Fig. 1 schematically shows the angle adjustment mechanism, denoted by 1. It consists of the main components an inner bearing 2 by means of which is rotatably mounted along an axis A a internal means 3 supporting a bearing, called the intermediate bearing 4 for an outer part 5.

The outer part is then mounted in the inner member 2 along an axis B, which has an angle α relative to the axis A.

The outer part 5 in turn carries an outer bearing 6 for a shaft 9 of a working member 7, the position of which is indicated by an imaginary point 8. The axis of rotation of the working member 7, called C, is angled at an angle ß relative to axis B. The figure shows the angles d and ß being equal. This embodiment is also assumed in the following description of the preferred embodiment of the invention. At A = B it is gained that rotation in a plane, as in steering, can take place by simultaneous rotation with the same angle of rotation in both axes A and B, but in opposite directions of rotation. In the position shown in solid lines, it appears that the geometric conditions are such that the axis C can be set to constitute an extension to the axis A. The indication point 8 then lies on this axis A-C.

It can be said that the bearing 2 constitutes the supporting part of the mechanism and the working member 7 its part which can be adjusted in different positions. In the case of a steering device, this means that the bearing 2 would correspond to the wheel suspension supported by a suspension system, while the working member constitutes the vehicle wheel. Its angular setting thus corresponds to the angular setting of the axis C. This angular setting is possible to achieve with each angle within a cone, with its tip exiting the intersection between the axes A and B and and symmetrically located relative to the axis A. This means that the indication point 8 can be moved to any position on a spherical cap, the center angle of which is equal to 2 ß.

This was indicated in Fig. 1 where the center axis D indicates a rotation of the outer part 5 in the bearing 4 by 180 ° so that the point 8 has moved outside the center axis A-C of the device. If now the part 3 is rotated in the bearing 2, the point 8 will describe a circle around the common center axis A-C. This circle line is the largest possible at the assumed dimensions and the value of the angle ß. By turning the part 5 a smaller angle than 180 °, the point 8 can be made to pass a smaller circle and in this way every conceivable circle can be covered within the maxi grind and down to 0 at the position shown in solid lines in Fig. 1. In addition, by rotating the part 3, each angular position of the point 8 in each conceivable arc of a circle can be assumed. This means that the point 8 can within the maximum circle line by simultaneous rotation of the parts 3 and 5 in its bearings be made to assume each position within said maximum circle. At the same time, this means that the outer part 5 with its center axis C can be made to assume each angular position in relation to the axis A inside the imaginary cone, which is formed by rotation of the axis C about the axis A. Each such angular position with associated position of the point 8 is thus achieved by a certain ratio between the rotation of the part 3 in the bearing 2 and the rotation of the part 5 in the bearing 4, see the arrows. Likewise, the path of the movement of the point 8 between two positions can be determined by controlling the rotation ratio between the axis A and B and thus the rotation of the axis C. Thus, if the axis A and B, at d = ß, is rotated at the same angular velocity but in opposite directions point 8 will describe a straight line, which means that the working part 7 is only pivoted in one plane. By mutually different rotation in the two axes, it can be made to swing in all planes.

If the working part 7, if it is a vehicle wheel, is to rotate with its axle 9, this takes place in the bearing 6 around the angle-adjustable axle C. If the working part 7 is a driven wheel, it must be connected to a driving mechanism for its rotation.

When applied to a steering device for vehicles, this means that the main movement of the steering movement of the wheels, thus pivoting in a plane, can be achieved if the rotation in the axles A and B is synchronized, but directed in opposite directions. The pivoting of the two steerable wheels does not have to take place with the same angular deflection, but here, by allowing the synchronous movements of each wheel to have different values, the wheels can be given the different angular deflection required for the inner wheel to rotate. 25 30 (H CD “J \ o rr ning shall follow its rolling circle and the outer its larger rolling circle.

In addition to this main movement, angular movements for said compensation can also be performed by deviating from the synchrony between the rotation in the axes A and B, as will be explained later.

Thus, if the parts 2, 3 and 5 correspond to the basic design of the steering device and its trimming means for the different setting angles, then the working means 7 can be said to correspond to the steerable wheel itself. In addition to a bearing, which is indicated at 6, a braking device is required and for front-wheel drive cars a driving device. The latter shall allow the angulation of the center axis C relative to the axis A when rotation takes place along the axis B within the position D of the axis C. This can, as in known front-wheel drive constructions, be achieved by means of a drive joint.

In addition to the adjusting device 1 now described in principle, a control device is also required for effecting the coordinated rotations at the shafts A and B. This control device 10 must allow steering by turning the wheels with different angles of rotation for the inner and outer the wheel when cornering to adapt to the different large rolling circles. In addition, they shall allow changes to the wheel adjustment angles both for an initial tuning to a starting position and later changes for adaptation to different driving conditions. 10 15 20 25 m o -J: s u; (3 The principles of the control device are shown schematically, most closely as a block diagram in Fig. 2. In the figure, by analogy with the designations in Fig. 1), the two steerable wheels and by 1 their setting units are denoted by their principle corresponds to the principle stated in Fig. 1. The axes A, B, C in this figure have also been drawn in Fig. 2. Up to the setting units 1, control lines 15 and 16 are shown for rotation in the respective axes A and 17 and 18, respectively. for rotation in respective axles B. These movements are effected by This rotation of the steering wheel of the vehicle, denoted by 23. is connected to a distribution unit 22, which distributes the movements of the steering wheel to the two pairs of control lines 15, 17 and 16, 18, respectively.

The distribution unit 28 is then arranged to give the inner and the outer wheel a different angle of rotation when cornering. This difference in angle of rotation depends on the width of the vehicle, which is a constant, and the angle of rotation of the wheels, which represents the direction of steering, and its instantaneous value may thus be fed back so that different angles of rotation are obtained.

These units and their functions thus correspond to what is achieved with a conventional control device.

Each pair of control lines can also be actuated by means of angle adjusting units 24 and 25, respectively. As mentioned, in the present control device the rotation of the wheels for steering, i.e. pivoting in a plane, is effected by T1 (ID NJ v? .438 by is rotated synchronously in the opposite direction of rotation relative to each other. Angle adjustment, on the other hand, takes place in that the rotation in the two axles is mutually different. The distribution unit 22 causes the said synchronous rotation in the axles A and B The two units 24 and 25 are coordinated to their differentiation effect, which, however, need not be the same in all situations, by means of a coordination unit 26. This in turn is influenced to via the units 24 and make different angular adjustments adapted to different factors, these may be measured conditions such as down suspension of the steering wheels, whereby such factors can be sensed by a sensor unit 28. In addition, there can be a unit 29 for the original tuning to the setting angles, which are to apply as the basic setting. In addition, there may be a control unit 30, which is manually actuated by the driver.

The arrangement shown in Fig. 2 thus enables customary steering by turning the wheels in a plane by means of the steering wheel 23. In addition, the vehicle can be adjusted for certain starting angles by means of the trimming unit 29 and this can thus be done centrally with the unit 29 located in an easily accessible place. conventional control device trimming of each adjusting means separately. Temporarily, trimming of output 10 15 20 25 30 U1 (f),. \ _] Th NO (Ls.

The angles occur depending on various conditions such as the vehicle's unloading, the condition of the road surface or crosswinds while measuring how these conditions affect the bearing of the wheels against the road surface by means of the sensor unit 28. Finally, it can be arranged so that the driver can adapt the wheel setting to special conditions. such as off-road driving, for example. Alternatively, in order to have a simplified design, the sensor unit can be excluded and all trimming, for example adaptation to the vehicle's download, is left to the driver to operate by means of the unit 30.

It should also be mentioned here that the control device according to the invention can be provided with servo support. According to the commonly applied principle, there must be a mechanical connection between the steering wheel and the wheels, so that in the event of a loss of servo power, steering can still take place.

The setting units 1 and the control lines 15, 17, 16, 18 and the distribution unit 22 should thus be able to work mechanically in such a way that an external force can be applied for servo support.

Following this description of principles, the technical application of these principles will now be described by means of exemplary embodiments. Figures 3 and 4 show an embodiment in a vertical section with the adjusting device shown on an enlarged scale. In Fig. 3, the same reference numerals are used as in Fig. 2. On the other hand, the schematic representation in these LH C 10 15 20 25 30 -J \ -. [I \ Û figures replaced by a more technical depiction of an embodiment. In this case, the steerable wheel 7 is represented only by a tire profile, and is suspended on its axle pin 9, which with the bearing 6 is rotatably mounted in the adjusting device 1, which in turn is supported by the part 2 shown here as a axle tube.

The part 3, which is stored in the part 2, is shown as a housing, which via the bearing 4 supports the part 5, which also has the shape of a housing. This in turn carries the shaft journal 9, which is rotatable in the bearing 6, shown here as a ball bearing.

The axes A, B and C are marked as well as the fixed angle d between the axes A and B and the angle ß between the axes B and C. d and ß are equal. The shaft C of the shaft pin 9 is shown in a set angular position with A and C in line with each other. The largest deflection in the opposite direction is marked with the axis D.

With the support of Fig. 4, the embodiment is described more technically and with mechanical engineering nomenclature with reference to new reference numbers. For the working member thus the steerable wheel, a shaft pin 33 is shown on which the wheel with associated braking arrangement can be mounted non-rotatably on the pin. The pin is supported by a bearing 34 and is by this rotatably mounted in the housing 35, is carried by a wheel bracket 36. The wheel bracket 36 is the resilient positioning device, which in turn is suspended by means of a spring leg 37 and an arm 41, any other suspension device, for example comprising A drive shaft 38, however, only link arms are used. stored 10 15 20 25 507 494 B at 49, gearbox, steerable wheel at the other side of the vehicle. The drive shaft 38 is movably mounted at a gear (not shown) from which the corresponding drive shaft exits until it is connected to the shaft pin 33 via a drive joint 39, so that the drive connection can be maintained in different rotational positions of the shaft pin.

It further appears that the bearing 34 of the axle pin 33 is supported by an outer housing 40. The housing 40 is mounted via bearing 43 in an inner housing 42, which in turn is mounted via bearing 44 in the wheel bracket 36. The latter bearing represents the the aforesaid pivot axis A and the bearing 43 are so angled (by the angle d) that its center axis represents the axis B. The center axis of the shaft pin 33 in turn represents the axis C which is also shown and in the neutral position shown in Fig. 1, in fig. 3, it appears that the axis C is in turn angled with the angle ß = d from the axis B. This means that in this position the axis C and the axis A constitute an extension of each other.

To effect the rotation in the shaft B, on a hollow shaft 47 mounted in the housing 42 at 48, a gear ring 45 is arranged with its center axis in the shaft A. This is in engagement with a gear ring 46, which is connected to the bearing housing 40, at a place where the two toothed rings angled to each other meet (at the top in Fig. 4).

The housing 42 is also rotatable about the axis A while entraining the angled bearing 43 for the ring gear 46 on the housing 40. 'L 15 20 25 30 LV! From a comparison with Fig. 1 it appears that the said angle settings can be made within the imaginary cone, which has an acute angle by rotating the housing 40 along the hollow shaft 47 via the ring gear 46 and the gear ring 45 and thus pivoting of the bearing 34 for the wheel pin 33. In this case, as previously stated, a rotation of the wheel for steering in only one plane means that rotation in the axes A and B must take place synchronously but in mutually opposite directions (applies when the angles d and ß are equal in size).

Thus, in order to effect steering and angular adjustment by means of the control device 10, rotation of the two elements housing 42 and hollow shaft 47 with its ring gear 45 is required. The synchronous rotation for steering must then be effected by a connection to the steering wheel of the vehicle. As mentioned, asynchronous rotation starts from the units 24 and 25. Fig. 4 shows as an example how the coupling to the wheel adjustment units can be performed. The housing 42 is provided with an arm 50 intended to be connected to one of the drive lines 15/16 in a pair for rotating the housing 42. On the hollow shaft 47 supporting the toothed ring 45 is arranged a second arm 51, which is to be connected to the second drive line 17. / 18 for turning the housing 40.

The embodiment shown is only a conceivable embodiment. In particular, the power transmission between the steering wheel and the setting units can be performed in a number of different ways. Since the setting units must be movable 10 15 20 25 30 Ü during suspension in relation to the steering wheel, a corresponding possibility of movement in the drivelines is required. In addition to the arms 50, 51 specified here, this can be done, for example, by means of racks and, with the drive lines, slidable, flexible rods designed as flexible shafts, link systems or as hydraulic power transmission, for example.

The exemplary embodiment has referred to the steerable vehicle wheels, thus in the case of passenger cars and trucks the front wheels. Since the device according to the invention can be designed both for adjusting the wheel angles and pivoting for cornering, this application is probably the most interesting.

However, there may be a need for adjustment and adjustment of the wheel angles also at the other wheels of the vehicle, in the normal case thus the rear wheels of the vehicle. Here, too, you can gain benefits such as reduced tire wear by adapting the wheel angles to the suspension and other factors. It also happens that vehicles with front-wheel steering are provided with a change in the rolling angle of the rear wheel adapted to cornering, which gives a better cornering ability, especially at higher speeds.

In vehicles with bogie, increased tire wear occurs because the bogie wheels, which are set for rolling in a straight line when cornering, will accelerate laterally towards the 10 15 M road surface during the bogie's turn. An option for adjusting the wheel angles when turning would eliminate the said disadvantage.

In addition, there may be special vehicles such as vehicles for driving along narrow paths with sharp curves, where there is a need for steering options for all four wheels. Thus, although the device according to the invention is primarily intended for adjusting and adjusting the wheel angles and for turning the steerable wheels on a road vehicle, the inventive concept also includes other applications where a wheel adjusting device is required in a vehicle, examples of such cases have been given above.

Claims (7)

10 15 20 25 30 Un CD “\] $> \ O $> W Augusti. 1996 Ref. ALN951208 Patent claims Angle adjustment device for vehicle wheels at which the wheel is mounted by means of a wheel axle (9), which is arranged to be adjusted at different angles and thereby give the wheel for its unrolling an advantageous angular position with respect to wear and the road properties of the vehicle, characterized in that , that for the support of the wheel axle (9, 33) and thus the wheel, a preferably spring-suspended bracket (2, 36) is arranged on the vehicle in which a first bearing unit (3, 42) is mounted rotatably about a first axis of rotation (A), which first bearing unit carries a second bearing unit (5, 40) which is rotatable in the first bearing unit along an axis of rotation (B), the unit having a first angle deviating from the axis of rotation (A) of the first (G), (5) supports the wheel axle (9, 33) which second bearing unit at a second angle (ß) between the axis of rotation (C) of the wheel axle and the axis of rotation (B) of the bearing of the second bearing unit in the first bearing unit, whereby the wheel axle ro axis of rotation (C) can be pivoted at different angles relative to the axis of rotation (A) of the first bearing unit by rotating the second bearing unit in the axis of rotation (B) for its bearing in the CN 10 15 20 25 30 - ... I. eg M ..- .ffs first bearing unit and thereby in its more or less angular position in relation to the axis of rotation (A) of the first bearing unit can be moved in a circular path by turning the first (3) (2). simultaneous rotation of the first bearing unit in the (A) bearing unit in the bracket so that, through the first axis of rotation and the second bearing unit (B), the wheel axis can be adjusted at all angles within a second volume of the axis of rotation (C), the axis of rotation of which tip starts from the intersection of the axis of rotation (C) of the wheel axle and the axis of rotation of the second bearing unit bearing in the first and whose apex angle is determined by the bearing unit (ß), the magnitude of said second angle between the latter (C, B), 25, 26) simultaneous rotation of the first and the second two axes of rotation with a control device arranged for the storage unit, so that angular settings suitable for the driving of the vehicle for vehicle wheels provided with the angle adjusting device are obtained. Angle adjustment device according to claim 1, characterized in that the control device (24, 25, 26) (28, 29) for sensing external factors such as the vehicle therefrom, is connected to units arranged for loading, speed, road slope and crosswind, for example, and arranged to adjust via the control device the wheel angles for compensation of said factors during the driving of the vehicle. 10 15 20 25 30 W Angle adjusting device according to claim 1 or 2, is arranged at wheels, characterized in that the one which is controllable for cornering (24, 25, 26) (23) or similar control means for and that the control device is coupled to a control steering pivot of the respective wheel axle and thus wheels at the intended angle for cornering. Angle adjusting device according to claim 1, 2 or 3, characterized in that said two angles (d, ß) are mutually equal, whereby the axis of rotation (A) of the first bearing unit and the axis of rotation (C) of the wheel axle in a certain rotational position between the first and the second storage unit can be made to form a straight line. Angle adjusting device according to claims 3 and 4, characterized in that for pivoting the respective wheel axle (9, 33) for cornering, the control device (24, 25, 26) is arranged to turn the first and the second bearing unit (3). , 42-5,40) with the same angle, the value of which is determined by (23) angular deflection, with rotation of the two bearing units of the control wheel or similar guide means in opposite directions for pivoting the wheel axles substantially in one plane. Angle adjusting device according to any one of the preceding claims, characterized in that CH C3 10 15 20 25 30 \ f _. \ -Fix 20 (2) that the first storage unit (42) of said bracket (36), first housing is constituted by a wheel suspension unit (3) is constituted by one (5) is constituted by a second housing (40), in which the wheel axle (33) is and that the second bearing unit and which housing is mounted in the first housing in the (ß) (Å) wheel suspension unit ( 36), and that in the first housing (42) (Å) the wheel suspension unit mounted an inner shaft (47) with a (45) mounted bearing axis of rotation (B) at an angle relative to the axis of rotation of the second housing for its bearing in is concentric with its axis of rotation in which it engages a (46) (40) (42), with the two gears gears corresponding to gears on the second housing and inside the first housing forming a conical gear, which enables rotation of the second housing (42) by rotating the inner shaft (47), and that for said simultaneous a rotation of the first and the second housing means (50, 51) (24, 25, 26) are arranged partly at that and partly at said inner shaft (47), for coupling to the control device (42) with which the two coupling means can be pivoted around shoulders (A). first housing concentric with the axis of rotation of the first housing 7. 6, arranged at a steerable and driven wheel, wherein the Angle Adjusting device according to claim 1, characterized in that it is the inner shaft (47) is arranged as a tube shaft and is passed through for a drive shaft (38) arranged therein, (39) the drive shaft mounted in the second housing (40) is connected to the one in (33). which by means of a drive knot