CS325290A2 - Power assisted steering for vehicles - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering column servo drive steering apparatus with a steering column coupled to a steering column and an electric servo motor that generates a rotational support torque in the transmission in the transmission.

Power steering or steering vehicles have steering-assisted motor support to significantly improve ride comfort. They can be implemented with all kinds of steering control for motor vehicles, such as rack-mounted steering, worm steering, spindle steering or ball-or-ball control. Most servo controls work hydraulically with a separate conveyor pump, the flow of which is distributed symmetrically on both sides of the cylinder. The pressure difference produced by the control generates a proportional torque in the steering gear, for example a shoe or spindle, and thus a steering column.

Only electric servo controls are already known, in which a torque-boosting control is provided to the steering gear and to the steering column by an electric servomotor which is in continuous engagement. The servo controls work on the principle of so-called long-term management. In the already proposed servo control by the electric servomotor described in the patent application DE 38 24 424.1, two brake discs are provided which are coaxial with the steering column, are driven by a servomotor and rotate in opposite directions, one of which rotates in one of the two steering directions of steering column. The brake device, which optionally operates on one of the brake discs, produces a braking torque in dependence on the torque applied to the steering column in the direction of the torque of the rotating wheel. By applying this braking torque, the brake housing rotates against the servomotor in the same direction as the steering wheel or steering column. This in the same direction-acting torque is transmitted to the steering column and supports its rotational movement. The steering column and the gearbox are rigidly connected to each other by a torsion bar. The main advantages of this power steering system are that any electric power steering is compact, largely free of wear and is very advantageous from the standpoint of assembly, and if the servomotor breaks down, it is still possible to control the load.

The main disadvantages of this solution are that it is relatively costly and that it does not always lie 4 to ensure complete independent reliability.

The above drawbacks are remedied by the servo control according to the invention, the principle being that the servo motor is reversed, that the steering column and the steering gear input shaft are connected to each other in a manner permitting only a limited relative rotation such that the relative rotation of the sensing sensor is proportional to the sensed a signal that a control circuit is provided, which actuates the torque delivered by the servomotor depending on the sensed signal, and that a steering column controlled by a two-way idle is provided in the power shaft with the actuator output shaft and the steering gear shaft; , the axes relative rotation of the steering column to the input shaft form a rotary connection between the output shaft of the actuator and the input shaft of the steering gear.

The main advantages of the solution according to the invention are, in addition to the already mentioned advantages of electric power steering, in that it has a very large production and assembly cost, that it is highly reliable and that it ensures a substantial increase in driving comfort for vehicles below 1000 kg. scales, making it particularly suitable for vehicles of lower and middle 5 classes.

The servo control's own reliability is ensured by idling, which prevents unwanted steering movement if the servomotor is actuated in the event of a malfunction or if it runs too fast. In such cases, idling enters operation and releases the non-rotatable connection between the steering column and the steering gear input shaft. thereby reducing the necessary relative rotation of the steering column relative to the steering gear input shaft for connection. If the servomotor is blocked or the steering wheel jerks, the vehicle can be driven with a load-bearing capacity, as the frictional moments in the steering gear are only multiplied.

The measures set forth in the further paragraphs 2 to 31 of the definition of the subject matter of the invention are further advantageous improvements of the servo control according to point 1 of the definition of the invention.

According to a preferred embodiment of the invention, the freewheel drive part connected to the output shaft of the actuator has a driven part connected by an intermediate shaft of the steering gear and to a steering column connected to it. In this case, the idling speed is such that the steering part creates a

6 to control such a non-rotatable connection between the drive-driven part as long as the driving part does not rotate faster than the steering part which follows the pivoting movement of the steering column. The driving part is formed by an outer ring with an outer ring gear which engages the gear slowly, driven by the output shaft of the actuator. The driven part is formed by a coaxial inner ring which is non-rotatably connected to the input shaft of the transmission. The connection of the two is formed by rollers which are inserted into the recesses in the inner ring and which support the outer ring. The rollers are guided and can be moved in the circumferential direction, thereby creating an idling or clamping effect through the inner ring and the outer ring.

If, according to a further embodiment of the invention, the outer ring is formed in two parts in the radial direction and the two parts of the ring are connected to each other by means of a flexible insert ring, the radial elasticity of the outer ring can be formed, which is in the engagement with the gear ratio of 0-0.3 mm. .This can be used to compensate for the production range and also to achieve radial preload of the gears that are in mutual engagement. In the circumferential direction biased in the axial direction of the gears, an axially significantly shorter gearwheel is provided which has the same rigidity in both directions of rotation. In addition to releasing, noise can also be prevented when changing the sides of the toothed wheels. The tangential elasticity of the intermediate ring also allows damping

If, according to a preferred embodiment of the invention, the surfaces of the two parts of the ring, the abutting elastic intermediate ring, are formed with coarse teeth, the control of the radial and tangential elasticity according to the requirements is allowed.

If, according to another embodiment of the invention, the steering column connection and the steering gear input shaft form a relatively rigid rotating member with considerable progress, only a slightly soft steering column is obtained than with conventional steering without steering support. Strong progression makes it possible to achieve a soft fit at maximum rotation angle. As a rotary member, a torsion bar with an additional leading ball or a coaxial bent ring that is coaxial to the steering column and the input shaft can be used and is mounted on segments arranged with a slot gap in the circumferential direction side by side and non-rotatably connected alternately. a steering column and with an input shaft, or an annular arrangement of helical compression springs which, on the one hand, bear on a support part, non-rotatably connected to the steering column, and on the other side on a support part, non-rotatably connected to the input shaft ,

According to a preferred embodiment of the invention, the servomotor is designed as a DC motor which is arranged in the bridge web of the bridge connection. A controllable switch is arranged in each bridge web, and two switches in the bridge circuit are arranged simultaneously for switching on and off. shutdown. The switch actuation control signal is derived from the steering column rotation direction. The switches can be designed as controllable semiconductor switches or as mechanical or electrical control contacts. In the latter examples, the switching contacts are actuated by a switching contact control device which, in dependence on the direction of relative rotation between the steering column and the input shaft, always closes the current switching contacts and opens all switching contacts in the zero relative rotation position. A controllable semiconductor, which is controlled by a keying rate determined by the amplitude of the sensed signal, is arranged in series with the bridge circuit provided with the contact to control the DC motor torque depending on the sensed relative rotation value signal of the steering column and the input shaft of the steering gear. When creating bridge switch switches as semiconductor switches, one semiconductor switch in one of the two bridge branches can be used to control the torque.

According to a further preferred embodiment of the invention, a switching contact of the main relay is arranged in a series with a bridge circuit, which switches to a value below the predetermined speed of the motor vehicle. Thereby, the support of the control force is provided by the electric motor passivated from a certain speed limit. This provides support for steering, parking and low vehicle speed control, where mechanical steering with high steering column stiffness is provided in the high speed range.

According to a further preferred embodiment of the present invention, there is provided a gear for detecting a gear in the first gear forward, reverse gear, or gear lever position in the neutral position, and additionally providing additional reliability for the main relay. that there is a failure of the vehicle speed detecting device.

The device according to the invention has the advantage of having the advantage of providing a low-cost and reliable power steering aggregate which substantially increases the convenience of small passenger vehicles up to 1000 kg. It is particularly suitable as a parking aid for speeds below 15 km / h, but with the relatively steep formation of a rotatable member connecting the steering column to the input, the steering gear shaft can also be used as a power steering over the parking area.

Further measures such as those set forth in points 33 to 53 of the subject matter of the invention can be made to further improve the control system set forth in point 32 of the subject matter of the invention.

According to a preferred embodiment of the invention, the slip clutch consists of two clutch disks driven by a servomotor in opposite directions and oppositely disposed opposite clutch parts, which is connected to the input shaft of the transmission by means of a single-stage or multi-stage pattern.

The slip clutch can be electromagnetic or can only be operated mechanically. In this case it is formed as a friction clutch. In the first of these cases, the field windings are controlled by a control circuit depending on the electrically detected relative rotation, for example by the eddy current sensor, between the steering column and the steering gear input shaft. Depending on the direction of relative rotation, either one or the other of the clutch discs is pushed against the opposite clutch portion and thus the input shaft of the steering gear is driven by the servomotor. The slippage that arises between the clutch disc and the opposite clutch portion is dependent on the relative rotational value between the steering column and the steering gear input shaft, thereby providing a support torque to the input shaft of the transmission, which is based on the seromotor and it depends on the size of the relative rotation. The advantage of the electric clutch lies in the possibility of soft connection and soft disconnection of the steering support force j when reaching the limit speed. The freewheeling, which prevents the driver from limiting in the case of jerky movements of the steering wheel, can be secured in an electronic way in such a way that the clutch is disengaged in the event of rapid signal changes on the eddy current sensor, such as twitching of the column. The electric clutch must be made only for the maximum allowable torque of the motor and can therefore be very small. the mulching windings can be rotated with the opposing coupling portion, wherein the energizing current is fed through the friction rings, or can be fixed. The latter arrangement requires a somewhat larger structural space and offers the advantage that wear-resistant friction rings are eliminated. When forming a slip clutch as a mechanically actuated friction clutch, the opposed clutch portion is formed as a rotatable and axially slidable disk, which is pressed by a sensing device to the relative rotational direction between the steering column and the steering gear input shaft to one or the other clutch disk by such a pressing force, which is dependent on the relative rotational torque, the occlusion that arises between the two discs and thus the servo motor input shaft of the steering gear being supplied by the auxiliary torque is determined by the magnitude of the relative steering column rotation, the winding device being formed by a threaded drive with steep thread balls or a rectifier unit for converting the rotary movement to an axial ponyb.

If the two servo controls are completely mechanically formed between the servo motor and the idle clutch disks driven by it, which is controlled, for example, by centrifugal force, the servo actuator passes over the steering wheel during jerky movements of the steering wheel and prevents it from overloading. In both slip clutches, the clutch discs are preferably provided in oil. In order to avoid the losses caused by the stitching, it is preferable, in accordance with the invention, to provide only a single-stage actuator and to drive the servo-rectifier drive. negligible moments of inertia. In the adjustment of the idle, it is advantageous to position the idle in both small, angled wheels of the baffle and to allow the servomotor to enter the rectifier drive directly.

According to a further advantageous embodiment of the invention, the slipping clutch is designed as a reversible frictional drive with two fixed friction discs which are displaceably fixed relative to one another and driven by a servomotor and which is arranged between the two friction discs. on a pivot axis that is parallel to the friction discs. The sensing device is a rectifier unit that converts the rotary movement of the steering column relative to the steering gear input shaft to axially move the friction discs, thereby moving the friction discs together in one or the other of the axial direction according to the direction of the steering column relative rotation and one of the frictional the discs is pressed against the friction wheel by such a pressing force, which depends on the size of said relative rotation.

To connect the steering column and the steering gear input shaft, a rotating member is used in all examples of steering gear guidance, for example a simple torsion or swivel rod, which, when disengaging the steering above a specified speed limit, produces a direct steering force transmission from the steering column to the steering gear input shaft. . For operation of the mechanically formed sensing devices, this rod cannot be so rigid as is desirable for direct management. Therefore, according to a preferred embodiment of the invention, a friction device can be provided in a friction clutch servo drive or a friction drive friction drive, forming a rotatably rigid connection between the steering column and the input shaft 15 of the steering gear by means of a suitable centering device. it is possible to achieve a soft connection and to disconnect the steering support when reaching the speed limit.

The invention is illustrated in more detail below with reference to the accompanying drawings.

FIG. 1 is a sectional view of a longitudinal section through a power steering for a passenger car. Naobr. 2 is a section along the line II - II of FIG. 1;

FIG. 3 is the same view as FIG. 2, but of the modified servo control of the examples, left and right.

FIG. 4 shows a sectional view of a longitudinal section of a power steering according to another example of a conduit. FIG. 5 is a section along line V - Vz of FIG. 4.

FIG. 0 shows a sectional view of a longitudinal section of a power steering according to a third example of a conduit.

Fig. 7 shows a sectional view of a longitudinal section of a power steering according to a fourth example of a conduit. Fig. S is a sectional view taken along line 16 VIII - VIII of Fig. 7.

Fig. 9 shows the electric wiring diagram of the power steering of Fig. 1;

Fig. 10 shows the electric wiring diagram of the power steering of Fig. 6.

Fig. 1.1 shows a schematic view of a longitudinal section of the device according to the fifth embodiment.

Fig. 12 is a schematic view of a longitudinal sectional view of a power steering according to a sixth embodiment.

Fig. 13 is a schematic view of a longitudinal sectional view of a power steering according to a seventh embodiment.

Fig. 14 is a plan view of the centering device for the power steering of Fig. 12.

Figures 15 and 16 show plan views of the servo steering idle of Figures 12 or 13 according to two exemplary embodiments, in partial section.

The steering column 10 is a part of a steering device whose section of the longitudinal section is shown in FIG. 1. At the upper end of the steering column 10, which is shown on the left in FIG. a steering shaft 11 of a steering gear (not shown) which rests on the steering column 12o via a needle bearing 12o. The steering column 10 is rotatably supported by its longitudinal axis by means of a ball bearing 13 in the steering housing 14. The steering column 10 and the input shaft 11 are connected to one another by means of a relatively rigid pivot member 15 with high progressivity, thereby allowing a limited relative rotation of the steering column 10 and the input shaft 11. Electric servomotor 16 (FIG. 9) which is formed by a reversible, permanent magnet excited DC motor, driven by a reducer 17 by an external idler ring 19 which is provided with an external toothed gear 18. The outer ring 19 is pivotally mounted on the input shaft 11 via a ball bearing 21. 2, the idle 20 still has a co-axial inner ring 22 with respect to the outer ring 19, which, as will be described in greater detail, is non-rotatably connected to the input shaft 11. A cage 23 is arranged between the outer ring 19 and the inner ring 22. which, as will be next described in more detail, is non-rotatably coupled to the control element 10. The control cage 23 engages with the control arms 18, 24, viewed in the circumferential direction before and by one roller 26 which is received in the recess 27 in the inner ring 22 and which rests between the inner ring 22 and the outer ring 19 Three rollers 26 and recesses 27 are arranged in each case, which are arranged on a circumference with offset at the same angle of 120 °. Each recess 27 has a central section 27a and two lateral sections 27b on the side thereof, the depth of which is end diminishes. If the rollers 26 are disposed in the central section 27a, the outer ring 19 can rotate freely relative to the inner ring 22 and roll on the rollers 26. As the rollers 26 are pushed into one of the two side sections 27b, a clamping between the outer ring 19 occurs. and the inner ring 22, so that they are not rotatably connected to each other. The rollers 26 and 26 control the controllers 24, 25 and the control cage 23 connected to the steering column 10.

As shown in FIG. 2, the outer ring 19 can be viewed as a two-piece in the view of the axial direction, whereby a resilient insert layer 28 is provided between the two parts 19a and 19b of the ring formed as an intermediate ring. 19 on the elastic intermediate layer 28 are formed with a bevel gear. By means of this intermediate ring 28, which is generally made of elastomer, radial elasticity of 0-0.3 mm can be achieved, thereby compensating for the manufacturing clearance. The tangential elasticity of the intermediate ring 28 also allows damping. Due to the radial elasticity, it is possible to radially bias the outer ring 19, that is to say its outer ring 18, and with it the geared gear 29 of the reducer 17, which not only prevents the occurrence of noise during the alternation of the teeth but also allows in the axial direction, a narrower narrower wheel, which has the same stiffness in both directions of rotation. However, the intermediate ring 28, or the flexible inserts, may not be formed at all.

Since some elastomers, such as natural rubber, have poor shape stability, especially when heated, spiral clamping pins 68 are used to adjust the servo control in the area of the intermediate ring 28, which connect the two coaxial portions 19a to each other. These outer spring elements provide additional mechanical support and thus provide less strain on the intermediate ring 28. In the embodiment shown in FIG. 8, the elastic intermediate layer 69 is in the form of a meander and has alternating portions 69a and 69b alternating in radial and circumferential direction. 1 in this case, various elements are provided for additional mechanical support in the form of spiral clamping pins 68, which are expediently disposed in the radially directed sections 69a. As a result, the spiral clamping pins 68 are mainly subjected to pressure and not to shearing so that they can be made thinner, instead of the spiral clamping pins 68, other spring elements such as leaf springs can also be used in the two exemplary embodiments shown in FIG. . Since the other components of FIG. 3 are identical to those of FIG. 2, no reference is made to these parts by reference. Reference is made to Fig. 2 and the corresponding description. 1 and 2, the pivot member 15 is a bent bent ring 30 which is coaxial with the steering column 19 and the steering gear input shaft 11 and is mounted on segments 31n32 arranged side by side in the circumferential direction of the gap. The fastening is carried out by means of pressure plates 33 or 34, the dimension of which in the circumferential direction is substantially smaller than that of the segments 31, 32, the pressure plates 33, 34 being bolted to the segments 31, 32 for By means of countersunk bolts 35 as shown in FIG. 1. The bent ring 30 is clamped by the intermediate plates 33, 34 and between the segments 31, 32.

The segments 31, 32 are more curved on the outer periphery in the direction of their edges, thereby forming in the peripheral region of the segments 31, 32, the outer periphery of the segments 31, 32 and the bent ring 30 in the direction of the edges of the segments 31, 32 increasing the radial air gap 91. By means of the pressure plates 33, 34, damping elements 36 are provided in the circumferential direction. As can be seen in particular from FIG. 1, the segments 31 are fastened together on the carrier disk 37, which is non-rotatably connected to the steering column 10 and is preferably formed in one piece with it. The aforementioned non-rotatable disk-shaped control cage 23 which carries the control arms 24, 25 for the rollers 20, as shown in FIG. they are screwed into the holes 39 with the threads in the segments 31. As can be seen from FIG. 2 and also in FIG. 6, the segments 32 are made of one piece and thus non-rotatably connected to the input shaft 11 of the steering gear. idle inner ring 22.

A sensor 40 is provided in the steering box 14, which senses the relative rotation between the steering column 10 and the input shaft 11 and provides a signal which is proportional to this relative rotation, the sensor 40 being an example of our. 1 is formed as a eddy current sensor and consists of two mutually opposed sliding discs 41, 42, interposed therebetween, in this case a sliding bearing not shown and a support plate 43 on which the spools are adjusted. The support plate 43 is mounted on the control shaft 14, the slit disk 41 on the steering column 10 and the slot disk 42 on the inner ring 22. The coils are passed through alternating current. When the swivel member 15 is rotated and the relative steering rotation of the steering column 10 is connected to it, a different overlap of the slotted discs 41, 42 with the degree of rotation is produced against the input shaft 11. This leads to a greater damping of the sensor signal 40, thereby obtaining a swiveling dimension of the pivot member 15. This signal sensor 40 serves to control the seromotor torque 1b as a function of the relative amount of steering steering column 10 relative to the input shaft 11 of the steering gear. . 23

Fig. 9 shows a schematic of the connection of the servomotor 16 ný The DC servomotor 16s permanently excited by the magnets with the derivation characteristic is arranged in the branch 44a of the bridge circuit 44, which is arranged in series with the switching contact 45a of only the schematically represented main. relay 45 and the vehicle control switch 46 on the vehicle battery 47. There are four controllable switches arranged in the bridge circuit 44, which, in the present case, are constructed as npn-transistors 51, 52, 53, 54. the transistors 51, 52, 53, 54 are connected to a control circuit 50 into which feeds the sensed eddy current signal sensor 40. From the sensor signal 40, the control circuit 50 can determine the direction of rotation of the rotating member 15 and accordingly control the direction of rotation of either the transistors 51 and 52 or transistors 53a 54, said pair always operating simultaneously, thereby rotating the servomotor 16 in the same direction of rotation. the transistor 52 or 54 is fully open, whereas the transistor 51, or 53 is controlled by the t / acím keying ratio, which is determined by the signal amplitude of the sensor 40 and which is proportional to the rotation of the rotary member lo or vice versa . the keying ratio t / T is determined by means of the 24 key 55 of the keying ratio in the bridge branch 44a of the wiring harness 44 and a no signal circuit 50 is reported. This drives the main relay 45 so that the switching contact 45a is closed when the keying ratio t / f ' is 0.95 and is opened when this torch is exceeded. Optionally, a sensor is also provided in the form of a vehicle speed detecting device 48. If the vehicle speed is a predetermined torque, the speed detecting device 4b carries the corresponding signal to the control circuit 50. If the signal is in disposition, the control circuit 50 is in operation. The operation is discarded, the passive passivated, whereby the servo motor 1b is also stopped by opening the main relay 4o if the vehicle speed exceeds the determined noonot. As shown in phantom in FIG. 9, a further sensor may be provided in the form of a transducer 49. This requires a signal to be activated on the control circuit 50 only when the shifting lever is in the off position when a forward forward or reverse gear is engaged. the activation signals from the devices 48 and 49 are connected by a logic device, so that the control circuit 50 can close the main relay 4o only the tenuy, both activation signals are available. 2ο The operation of the described power steering is explained below.

If the vehicle control switch 46 is closed, the vehicle is stationary or has a slight driving speed, and if a first forward or reverse gear is engaged or the shift lever is in the neutral position, the control circuit 50 actuates the main relay 45 and closes the switching contact. 45a of the main relay 45. Thus, the bridge circuit 44 is connected to the vehicle battery 47.

If a steering motion is made on the steering wheel, the steering column 10 rotates in one or the other direction. The transmission input shaft 11 is first fixed to the steering, and the rotary member 15 is rotated accordingly. This rotation of the rotary member 15 detects the eddy current sensor 40 and drives it as a sensed signal to the control circuit 50. This acts in accordance with the steering column rotation direction either on transistors 51 and 52, or transistors 53 and 54, thereby moving the servomotor 16 in the same direction of rotation, the steering column 10 being rotated. While the transistor 52 or transistor 54 is fully controlled, the transducers 51, 53, respectively, are control pulses with a keying ratio determined by the sensing signal or vice versa. Accordingly, the motor current is set and the servomotor 16 provides a torque proportional to the rotation of the rotary member 15 at its output shaft. The output shaft of the actuator 16 is driven by a reducer 17 the outer ring 19 of the idle 20. If for example, by rotating the pivot member 15 in the clockwise direction by means of a steering column 10, the idle outer ring 19 is also clockwise as shown in FIG. 1. The steering cage is also rotated when the steering column 10 is rotated clockwise. 2 3 in the clockwise direction, thereby releasing the control arm 25 of the control cage 23 of the rollers 26. The recesses 27 are now pulled into the tapered side sections 27b of the recess 27 by the outer ring 19, whereby the intermediate ring 22 and the outer ring 19 are clamped and thus the force from the servomotor 16 is allowed. through the reducer 17, the outer ring 19 and the inner ring 22 to the input shaft 11 of the steering gear. If, now, by turning the steering wheel and the three anti-clockwise steering columns 10, the rotation of the pivot member 15 is taken backward by the decreasing sensed signal from the control circuit 50 and the actuator 16. Near the zero position of the pivot member 15, in which no rotation of the pivot member 15 is performed, the pegs 26 are control arms 25 of the control cage 23 and extend the side sections 27b of the recess 27 and are held in the middle sections 27a.

If the servo motor 16 is set to full power due to the failure of the control circuit 56 or one of the twin-operated transistors 51, 52 or 53, 54, the inner ring 22 is overtaken by the outer ring 19 which is driven by the seromotor 16. In this case, the rollers 26 are also retained by the control arms 25 or control arms 24 in the counter-clockwise rotation, in the central sections 27a of the recess 27. Thus, the outer ring 19 can rotate freely even when the inner ring 22 is stopped. and eliminates the influence of the steering gear input shaft 11, thereby eliminating the risk of spontaneous steering. When the servomotor 16 is broken, i.e. when the outer ring 19 is stopped or even firmly braked, or at the high control torque requirement, in the passivated power steering, i.e. by the main relay 45 disconnected by the actuator 16, clockwise the rollers 26 are pushed by the control arms 24 into the side sections 27b of the deflection 27. Since the outer ring 19 does not move, no self-locking can occur, only a minor additional frictional moment arises. The control is carried out with the force exerted directly by the straight line through the steering member 15 on the input shaft 11.

The servo control described is effective as a parking aid or as a power steering for slow vehicle speeds. Once a gear is engaged or when the vehicle speed exceeds a predetermined speed level, the control circuit 50 interrupts the operation of the main relay 45 and the switch contact 45a opens, thereby disengaging the power steering. from steering column 10 through pivoting member 15 to steering gear output shaft 11. With respect to the relatively rigid pivot member 15 with strong progression, it is not possible to override the predetermined intermediate intermediate influence on the mechanical steering. The steering column of the steering column 10 roughly corresponds to the rigidity of the power steering vehicles. Disconnecting the main relay 45 and the associated switching contact opening 45a is an additional safeguard if the motor current exceeds a certain size due to a malfunctioning transistor 29 51 or 53 and there is a risk of servo steering overrun. 4 and 5, a pivoting member 15 ' is provided against the actuator according to FIGS. 1 and 2. In this case, it is formed by two compression springs 56, 57, which are disposed opposite each other in the axis of the steering column 10, or of the input shaft 11 with parallel axes and which act against each other. The number of helical compression springs may be increased and may, for example, be four or six, and the counter-acting helical compression springs are in pairs. The helical compression springs 56, 57 are supported on pins 58, 59, which are formed on the disk-shaped support portions 60 and 61. The support portion 60 is connected non-rotatably to the steering column 10 and the support portion 61 is connected non-rotatably to the input shaft. 11 steering gear. 60

The pin 58 is injected onto the bore portion of the pin 59 on the support portion 61. In the arrangement of the two springs, a helical compression spring 56 and a helical compression spring 57 are supported on the pin 58 of the carrier portion 60.

In order to avoid the deflection of the helical compression springs 56, 57 transverse to the direction of their action, the supporting portions 60, 61 are bulged in the region of the helical 30 compression springs 56, 57 in the form of half-shells so as to embrace the helical compression springs 56, 57 in their longitudinal direction pockets. By appropriately arranging the stepping of the helical compression springs 56, 57, the desired progressivity of the pivot member 115 can be adjusted. 3 the idler 20 inner ring 22 is non-rotatably supported by the support portion 61, while the idle control cage 23 is non-rotatably coupled to the support portion 60. A support ring 60, for example made of rubber, is placed on the support portion 60 formed therewith and the concentric inner ring 22 of the freewheel 20. Otherwise, the idling design 20 is the same as described in FIG. 1 and 2.

FIG. 10 shows an electrical circuit diagram of another embodiment of the servo control. This embodiment differs from the previously described servo control that the switches in the wiring diagram 44 of the DC motor 16 are designed as mechanical switching contacts 6, 3, 64, 65, 66. 64, 65, 66 are actuated by the switching contact control device 70 shown in FIGS. 6 or 7. In principle, the device operates such that, depending on the direction of relative rotation between the steering column 10 and the input shaft 11 of the steering gear always engages diagonally opposite switching contacts 63, 64, or 65, 66 in the bridge 31 of the steering gear. In the zero position of the relative rotation between the steering column 10 and the input shaft 11, i.e. at zero relative rotation, all switching contacts 63, 64, 65, 66 are open. In the series with bridge circuit 44, a semiconductor switch 67 is arranged, for example a transistor, which is controlled by the control circuit 50 again with the keying ratio t / T, which is determined by the amplitude of the sensed signal. In addition, the control circuit 50 is designed so that when the predetermined vehicle speed is not reached or exceeded, which leads to the actuator 16 being connected or disconnected via the main relay 45, the respective switching contacts 63, 64, 65, 66, or the semiconductor switch 67 are respectively by means of a time-delayed or increasingly-decreasing control voltage, the time delay, or the timing advance is only a few milliseconds. In this way, when the main relay 45 is closed, or when the main relay 45 is opened, the full battery voltage is not eventually disconnected from the servo motor 16, thus activating or passivating the servo drive slowly. As a result, even when the power steering is actuated, the sudden and unexpected control force is eliminated, which could lead to a driver error, especially when driving in a corner. Otherwise, all of the components in the wiring diagram of FIG. 10 agree with the parts of FIG. 9 and are therefore designated by the same reference numerals. An embodiment of the switching contact actuator 70 is shown in the servo control shown in longitudinal section in FIG. Except for the switching contacts control device 70, the servo control is exactly the same as that shown in FIG. 1, so the same components are designated by the same reference numerals. The switching contact control device 70 has a steep threaded drive 71 which includes a spiral groove 72 disposed on the steering column 10 as well as a guide nut 73 with balls 74 and guides 7 5. The guide nut 7-3 is guided axially movably through pins 76 in the segments 32 a pivot member 15 which is formed in one piece with the input shaft 11 of the steering gear. The balls 70 are pushed by radially sliding guides from the ring spring 77 to the sides of the guide track of the spiral groove 7. An actuating plate 78 is mounted on the free end face of the guide rail 73, which together with the control tongues 7, 9, which a control member 80 for the mechanical switching contacts 63, 64, 65, 66 according to FIG. 10 is mounted in the steering case 14. The actuating contacts 63, 64, 65, 66 are provided with release contacts and each of the two switching contacts 63, 64 and 6, 66 are merged into microswitches 81 and 82, as shown in FIG. 6. The switch pins 83, 84 of the microswitches 81, 82 are arranged on both sides of the control tongues 79 which are mounted on the microswitches 81, 82 facing away from the bearing pin 85 and supported by rollers86 on both sides of the control plate 78. 15, the guide nut73 performs an axial stroke in one or the other direction of the under-rotation direction of the pivot member 15. The control plate 78 swivels by means of the rollers 86 of one of the control tongues 79. Accordingly, the switch pin 83 or 84 of the microswitch 81 or 82 and the release switches of the microswitch are displaced 81 and 82, respectively, to their closed position. Depending on the direction of rotation of the rotating member 15, either the switching contacts 6, 3, or 64 or 65 and 66 and the servomotor 16 are connected in the respective direction of rotation. Only when the rotation of the pivot member 15 is reversed is the guide nut 73 together with the control plate 78 returned to its neutral position shown in FIG. 6. In this neutral position, the pegs 83, 84 are micro The switches 81, 82 are released to such an extent that they jump from the position in which they affected the contacts to their open position again. All switching contacts 63, 64, 65, 66 of Fig. 10 are in the open position. Control of the semiconductor switch 67 by a control circuit 50 with a sensed signal with a keying ratio t / T determined by the amplitude of the control circuit 50 of the input signal sensor 40 takes place as described in FIG. 10 such that the servo motor 16 provides the input shaft In the exemplary embodiment of the servo control according to FIGS. 7 and 8, otherwise, a switching actuator 70 is otherwise actuated with respect to FIG. 6. Otherwise, the no-change arrangement, the switching contact photo control 70 always has two in each of the segments 32 of the rotating member 15 mounted and fluid-filled cushions 87, 88 as shown in FIG. 89 with the piston rod 30 35 so that it can move in the axial direction in the displacement directions. The liquid filled cushions 87, 88 are arranged in the peripheral region of the segments 32 in which the segments 32 are more curved, thereby forming an air gap 91 between the bent ring 30 and the surface of the segments 32, as shown in FIG. To each fluid-filled cushion 87, 88, a large plate 92 of the piston 89 is attached to the bent ring 30 by means of a tappet 93 of the piston 89. The two piston rods 90 axially project from both segments 32 and are rigidly connected to the annularly-shaped actuator plate 94. The switching contacts of the bridge circuit 44 in Fig. 10 are formed by electrically actuated switching contacts of the switching relay, and the switching contacts which are always switched at the same time are combined into a double contact of the switching relay, which is always controlled by one relay winding. neck closure outputs The sensors 95 are each coupled to one relay winding of one of the two-way relays, and when the pivoting member 15 is rotated by the steering wheel in one or the other direction, corresponding sections of the bent ring 30 are inserted into the air gap 91. by means of tappets 93dec 93 of piston 59 and by piston plate 92 according to the direction of rotation on one of the two fluid-filled cushions 87 or 88. The pressure on the respective liquid-filled cushion 87 or 88 is transmitted to the piston89 and moves the piston rod 90 in a direction rotating the rotating member 15 in one or the other axial direction. As a result, the actuator member 94 and the movable part of the neck lock sensor 95 also move. According to the direction of travel, the neck lock sensor 95 actuates the second switching relay, so that the relay doubling contacts 63, 64 or 65, 66 (FIG. 10) are closed.

Instead of the neck locking sensor 95, the actuator according to FIGS. 7 and 8 may be provided with a control member 80 for actuating the mechanical switching contacts 63, 64, 65, 66 in FIG. 6, which controls the microswitches 81, 82 in the same manner by means of the control tabs.

Of course, the actuator 80 shown in FIG. 6 can also be used to replace the actuating member 80 with the neck locking sensor 95 of FIG. 7. In such a case, the actuating device 70 of the switching contacts is suitable for actuating electrical switching contacts, FIG. for example, relay contacts which are provided in conjunction with the actuation device 70 of the switching contacts of FIG. 7. All of the above described embodiments of servo control, which is available as a parking aid, have servo controls which are also useful as an aid to with parking and which is provided with a slip clutch, the advantage of being significantly more efficient because slippage losses do not occur. The sero-motor 16 overload protection can be easily ensured by interfering with the semiconductor switch 67.

FIG. 11 shows a longitudinal section and a schematic representation of a power steering device 110 which has a steering control 110 at the upper end which is shown in FIG. 11, a steering wheel (not shown) is rotatably mounted. An input shaft 111 of a steering gear (not shown) is arranged coaxially with the steering column 110, which is likewise rotatable in the same way as the steering column 110. The steering column 110 and the input shaft 111 are aligned and connected to one another by a tumbler member 115, which is designed as a torsion bar, thereby allowing limited relative rotation of the steering column 110 and the input shaft 111. a permanent magnet excited DC motor that rotates at a constant speed in one single direction of rotation can be connected via a bi-directional slip joint 112 to the steering gear input shaft 111, whereby the servo motor 116 can engage via its output shaft 113 with the input shaft 111 of the steering gear and thus provide a torque that encourages steering motion on the steering wheel in one or the other direction. The sensing device 114, which consists of a current sensor and a control circuit 150, detects the relative rotation of the steering column 110 relative to the input shaft 111 in both the direction of rotation and its size, and controls the slip clutch 112 such that it produces a clutch torque dependent on a non-volatile the rotation between the steering column 110 and the input shaft 111.

The bi-directional slip clutch 112 has two pivotally mounted clutch disks 11S, 119 and oppositely disposed opposing clutch portion 120. The two disks 1.18, 119 are driven by the servomotor 39, 116 through the reversing means 117 in opposite directions of rotation, the servomotor 116 driving directly with the reversing device 117 and the axes 118, 119 of the coupling being engaged with the gears of the reversing device 117. The opposite clutch portion 120 is connected via a single stage model 121 to a steering gear input shaft 111. In an altered design arrangement, the clutch disc 118 may be mounted non-rotatably to the output shaft 113 of the servo motor 116, such as the servo control of FIG. 12. In this case, section 121 is formed in two or more stages.

The opposite clutch portion 120 is formed of two parts, each portion 120a, 120b being associated with one disc 118 or 119 of the clutch. The two parts 120a and 120b are rigidly connected to each other and are mounted together on a hollow shaft 122 which is non-rotatably connected to the input shaft 123 of the original 121. The hollow shaft 122 extends through the hub 324 of the clutch disc 119 and serves as a bearing for the clutch disc 119. A shaft 125 engages in a hollow shaft 122, non-rotatably coupled to the clutch disk 118, rotatably mounted thereon, each portion 120a, 120b of the opposed clutch portion 120 carries an annular solenoid, of which only the solenoid 126 with the winding 127 in part 120b is shown The drive winding 127 is electrically conductively coupled via three on the input shaft 123 of the predetermined contact friction contacts 128 to the control coupling 150, which optionally drives the drive current to the field windings 127a or 120b of the clutch portion 120b. 120. If the field windings 127 of one of the sections 120a and 120b are under current, the adjacent clutch portion 120 is coupled to the associated wheel 118 or 119 of the coupling for rotatable drive. Depending on the magnitude of the electromagnetic force determined by the excitation current, slip occurs between the clutch disc 118 and the clutch opposite the clutch portion 120, so that a torque dependent on the sliding gear input shaft 111 is transmitted to the transmission input shaft 111 via a master 121. The sensing device 114, which consists of the eddy current sensor 14 and the control connection 150, determines the excitation current of the electromagnet 126 so that the slip is inversely proportional to the relative rotation of the steering column 13.0 for the input shaft 11.

The eddy current sensor 140 is formed as in FIG. 1 and consists of two-sided swiveling disc disks 141, 142, 41 of a sliding flange disposed between them and a carrier plate 143 which is provided with printed spools. The support plate 143 is mounted non-rotatably, while the slot disk 141 is mounted on the column 110 and the slot disk 142 is secured to the input shaft 111 by the sleeve 144. The coils are alternated current. Turning the pivot member 115 formed by the torsion bar and the associated relative rotation of the steering column 110 and the input shaft 111 results in a different overlap of the slot coils 141, 142 in accordance with the degree of rotation. This leads to more or less great damping of the high-frequency voltage present. In addition, this signal has the characteristic of the direction of rotation. This eddy current sensor signal 140 is applied to a control connection 150 which, according to the direction of relative rotation, energizes the field winding 127 of part 120a or part 120b of the clutch portion 120 to such an excitation that is determined by the amplitude of the output signal of the eddy current sensor 140 the servo control only uses the parking aid as an electric signal to characterize the speed in the vehicle. If this signal is greater than 42 a predetermined threshold, the field current will trip. The slip clutch 112 is open and the servo drive is out of order. The sequential connection or removal of this parking aid is possible by the fact that the control of the slip clutch 112 is not abruptly interrupted, but is effected continuously at a specified speed area. This avoids the unwanted twitching of the steering wheel at high torques. Furthermore, overload protection of the servomotor 116 can still be provided by the control circuit 150. In this case, the control connection 150 is supplied with an electrical signal that is proportional to the motor current I or the motor temperature. If this signal exceeds a predetermined value, the excitation current is also disconnected, thereby opening the slip clutch 112 and relieving the servomotor 116. 12, the opposite clutch portion 120 is formed as an axially displaceable friction disc 130, which is also non-rotatably coupled to the hollow shaft 122 and the input shaft 123 in the present case, a two-stage mold 121. in the present case it is formed purely mechanically and has a drive 131 with a thread and a ball which converts the rotational movement of the steering column 110 relative to the input shaft 111 of the steering gear to

An axial displacement is obtained which, by means of a two-arm swiveling lever 132, secures the corresponding axial slide disc 130, whereby the friction disc 130 is pressed either onto the clutch disc 118 or onto the clutch disc 119. In this way, the rotating disk 118 and / or the coupling 119 carries the friction disc 130, the slippage again being dependent on the magnitude of the relative rotation of the steering column 110 and the input shaft 111.

The threaded drive 131 of the drive portions 133 and 134 of the drive, which are provided with a yoke, in which the balls (not shown) are mounted, in the drive portion 133 is rigidly connected to the drive post 110, while the drive portion 134 is rotatably and axially slidably mounted on the housing 135, which is connected to the input shaft 111. A rotatably axially non-slidably movable sleeve 136 is mounted on the drive part 134, and the same slide sleeve 137 is mounted rotatably but axially displaceably on the input shaft 123 of the frame 121 'which is rigidly connected to the hollow shaft 122. the two slide tabs 136, 137 engage the two-arm pivot lever 132 at one end. The pivot axis 13S of the pivot lever 132 is arranged transversely to the direction of displacement of the slide sleeves 136, 137, thereby translating the axial movement of the slide sleeve 13b in the opposite direction to the axial displacement of the slide housing 137.

When a steering network is applied to the steering wheel, the torque from the steering column 110 is transmitted to the input shaft 111 of the steering gear via the pivot member 115 formed by the torsion bar. The relative relative rotation of the steering column 110 is changed by means of a threaded drive 131 to a axial displacement of the drive part 134 and thus of the sliding sleeve 136 which is proportional to the relative rotation between the steering column 110 and the input shaft 111. According to the relative direction in this case, the sliding sleeve 136 in FIG. 12 is moved to the left or right. This movement of the sliding sleeve 136 is converted by means of a pivot lever 132 to the corresponding sliding movement of the sliding sleeve 137 to the right or left, thereby abutting the friction disk 130 on the clutch disc 118 or clutch hub 119. Since the sliding path of the friction disc 130 is smaller than the sliding path of the sliding sleeve 136 driven by the threaded and ball drive 31, the friction disc 130 is more or less large in the frictional force of the corresponding clutch disc 118, 119 with the respective discs. the disc Π 8, or the 11.9 clutch with a greater or lesser slip corresponding to the torque torque is transmitted via the 45 two-stage pattern 121 to the output shaft 113 of the steering transmission.

Not the difference from servo control by. 11, the servo motor 116 drives the clutch disc 118 directly and drives the clutch disc 119 via a reversing device. Accordingly, template 121 is formed as a two-stage design. Here again, however, as with the servo control of FIG. 11, it is possible for the revolver gear 117 to be mounted on the output shaft 113 of the actuator 116 so as to engage the gear directly in the reverse gear 117. In this case, template 121 is again created as one-stage.

In order to enable the servo-motor 116 to perform fast interventions on the steering wheel while still limiting friction partly in the oil-moving clutch disks 118, 119 and the accelerated masses, the output shaft 113 of the servomotor 116 and the intermediate shaft 125, which is non-rotatably connected to with a clutch disc 118, arranged by centrifugal force controlled idling139. This idling 139 additionally creates an overload protector 116, and ensures that the servo motor 116 is disengaged when the servo control is disengaged. The output of the wings 113 of the servomotor 116 produces the idler shaft 139, while the idler shaft 139 represents the idle output shaft 139. As shown in FIG. 11, the reversing mouth 117 then assigns and arranges the idle 139 between the output shaft 113 of the actuator 116 and the input shaft of the reversing device 117 that carries the toothed wheel driving the clutch disc 118.

Figures 15 and 16 show two examples of centrifugal force controlled idling 139. Each idling 139 has an inner ring 1.4.5 connected to it with its drive shaft, in this case the output shaft 113, of the motor 116, coaxial with it. with its output shaft, in this case shaft 125 of the clutch disk 118, a non-rotatably connected outer ring 146, between the inner ring 145 and the outer ring 146 supporting the clamping body 147 and a centrifugal force-controlled steering cage 148. As the nip bodies 147 are formed as three rollers, they are distributed evenly around the circumference and are positioned λ-axial grooves 149 in the inner ring 145. Each axial groove 149 has, as seen in the circumferential direction, the areas in which the nip bodies 147 may move. When the clamp body 147 is moved into the area which is rearward in the direction of circulation of the inner ring 47 to 145 of the region 145, the inner ring 145 connects non-rotatably with the outer ring 146, i.e., they are in the clamped position. When the movable body 147 is moved into the front region of the axial groove 149 in the circulation direction 129, the inner ring 145 and the outer ring 146 are released for independent rotational movement so that they are in the idle position. The direction of circulation of the inner ring 145 coincides with the direction of circulation of the actuator 116. Since the inner ring 145 driven by the servomotor 116 rotates somewhat slightly through the shaft 125 loaded by the outer ring 146, it moves the clamping body 147 into the rearward area axial grooves 149 and occupy their position. In this way, the clutch disks 118, 119 are driven by the seromotor 116 via the reversing device 117. In the case of the steering wheel tug movements, the outer ring 146 rotates more quickly than the inner ring 145. In this way, the clamping bodies 147 are transferred from their clamping position to the idle half in the front. The outer ring 146 may move freely and may overturn the inner ring 145.

In order to control the centrifugally controlled control cage 148, three centrifugal weights 151 are provided, of which only one 48 of the centrifugal weight 151 is shown in FIG. 15, which is mounted at point 152 on the inner ring 14 5. The centrifugal weights 151 are connected by means of a tab 153 to the strip. 154, which pulls the centrifugal weights 151 inward. Centrifugal weights 151 engage with entrainers 155 in recesses 156 in control cage 148 to thereby shift the pivoting control cage 148 in circumferential direction. The springs 154 and centrifugal weights 151 are formed so that, when the lower ring of the inner ring 145 is not reached, the weights 151 are the springs 154 are pulled inwardly while rotating the outer ring control cage 148 of the inner ring running 145. The control cage. At the same time, the clamping bodies 147 move from their clamping position to the idle position, whereby the inner ring 145 can now freely rotate against the outer ring 146. This reliably prevents overload of the servomotor). 16, the portion of the control cage 14S constitutes a flexural suspension of the centrifugal weights 151 and a further portion of the control cage 148 constitutes a restriction on the path of the centrifugal weights 151 at a high number. speed. Centrifugal weights 151 are again connected to springs 154 by means of shims 153. 49

Usually, the power steering shown in Fig. 12, as well as the servo drive according to Fig. 11, is used as a parking aid. The predetermined speed limit of the vehicle is disengaged from the servo motor 116 and is controlled directly, while the torque of the steering column 110 is fed through the torsion bar 115 formed by the torsion bar, the drive shaft 111 of the steering gear. In order to avoid too soft steering, which could result in a transmission / torque over an overly soft-acting rod, a centering device 160 is provided between the steering column 110 and the input shaft 111 which actuates the passivation of the power steering above a predetermined speed. vehicle and which forms a rigid connection between the steering column 110 and the steering gear input shaft 111. An example of such a centering device 160 is shown in FIG. 14. A centering mouth has a radially protruding stop 161 on the steering column 110, a connecting joint mechanism 162 cooperating therewith, which is arranged on the input shaft 111 of the steering gear and drive 163 for actuation. The connecting articulation mechanism 162 has two double-arm pivot levers 164, 165 50 and two each at one end of the two-pivoted pivot lever 164, 165, pivoted connecting rods 166, 167, which are rotatably mounted on the articulated pivot lever 164 with their end facing away from the two-pivoted pivot lever 164. On their free ends, the two-armed pivoting levers 164, 165 bear on each side facing one of the abutment pads 171 and 172 respectively for receiving on the stops 161. The coupling joint mechanism 162 is configured such that by displacing the pivot pin 168 it occupies two end positions, 14 shows a solid line in dashed lines in which the bearing jaws are either fixedly fixed to the stop 161 or are spaced apart from the stop 161 at both sides in the closing position, which is shown in FIG. a fixed connection of the steering column 110 and the input shaft 111 is formed by the rigidly abutting abutment jaws 171, 172, respectively, of the connecting rod 166, 167 together with the articulated bolt 168 in the clara , in which the thrust force acting through the stop 161 of the jaw 171, 172 creates a displacement force on the articulated pin 168 which pushes the hinge pin 168 further into the locking position. Thereby, the articulated joint mechanism 162 is held in its locking position without force, whereby each pivoting movement of the post 110 51, y, y in the steering is transmitted without play to the input shaft 111 of the steering gear. Only by moving the hinge pin 168 out of this turret, caused by the drive 163, can the rigid connection of the steering column 110 and the input shaft 111 be removed.

The drive 163 has a helical spring i69 for converting the pivot pin 168 into a dead center and a electromotive spindle drive 170 for adjusting the preload of the helical spring 169 and for moving the pivot pin 168 to the end position with the release of the stop161. The spindle drive 170 consists of a spindle 174 which is driven by an electric motor 173 and a spindle nut 174 which can be screwed onto a spindle 174a on which a helical spring 169 is fastened. a servo motor 116, which is not controlled by a control unit (not shown). This actuates at its nominal speed. Thereafter, the electric motor 173, which, by means of a helical spring 16 9, pulls out the pivot pin 16_ in a time dependency or in dependence on the speed from the dead center, is connected. In this case, the pivoting levers 164, 165 swivel outwardly and the stop 161 is released for relative movement relative to the mating jaws 171, 173. As soon as the speed of the vehicle for passivation is reached again, the reversing motor 17 3 is inverted the direction of rotation, thereby increasing the preload of the helical spring 169, depending on the time or speed, until the helical spring 169 pushes the pivot pin 168 to the dead center. In this way, the pivoting levers 164, 165 are pivoted inwardly and the bearing jaws 171, 172 abut against the stop 161 on both sides. Thereafter, the servomotor 116 is disengaged. 160 when not reached, or when the vehicle speed limit is exceeded. This ensures that, on the one hand, if the speed limit of the vehicle is not reached, a permanently required minimum slip is provided for the no-friction, i.e., the slip clutch 112, which does not jolt in terms of friction, and the connection between the steering column and the reinforcement is formed when the vehicle's vehicle speed is exceeded. the steering gear input shaft 111 before the actuator 116 is disconnected.

FIG. 13 shows a further embodiment of a power steering which is actuated below a predetermined speed limit of the vehicle and thus allows the vehicle to be used as a parking aid in the area of lower speeds. The steering support is retracted in one direction and the uncontrolled rotating seromotor 116, which produces a torque on the input shaft 111 of the steering gear 111 via a slip coupling 112 "according to the direction of rotation of the steering column 110. The slip clutch 112 has two frictional the discs 181, 182 arranged in the axial spacing are connected to one another as well as the friction wheel driven by the seromotor 116. The idling speed 139, which is driven by the centrifugal force, is incorporated into the force path between the servomotor 116 and the friction wheel 183 The shaft 184 of the frictional wheel 183 is mounted transversely to the axis of rotation of the two friction discs 181; 182a, the friction wheel 183 extends between the two friction discs 181, 182 the displacement of the two friction discs 181, 182 is each one of which is applied to the friction wheel 183a is driven by the friction wheel 153, thereby circulating the two frictional discs 181, 182 in one or the other direction of rotation, depending on which of the friction discs 181 optionally, the friction wheel 183 engages. Despite this, the disks 181, 152 are arranged rotatably and axially slidably on the sleeve 18 which coaxially coalesces the pivot member 115 in the torsion bar support which connects the steering column 110 and the input shaft 111. Both friction discs 181, 182 are connected through the template 121 "with input shaft 111.

The sensing device 11411, like the sensing device 114 of FIG. 12, is formed purely mechanically and is formed by a baffle unit that converts the rotational movement of the steering column 120 relative to the steering gear input shaft 111 to the axial displacement of the two friction discs 181, 182. one of the friction discs 181, 182 is pressed against the friction coil 1 S3 by such a pressing force, the size of which depends on the size of the relative rotation. The rectifier unit consists of a planetary gear 186 with a crown wheel 187, a pinion 188 and two through an ISO wheel connected by planet wheels 189, 190, a spindle drive 1.91 with two parallel to the steering column 110 provided by the spindles 192, 193 it is connected to the friction discs 181, b 'rotatably but axially non-slidably and into which the spindle 192, 193 can be screwed. The paste 188 is non-rotatably connected to the steering column 110, the co-run wheel 167 being non-rotatably coupled to the sleeve 185 and Π P Τ Τ <Γ'ε * (ι, * 7/55 by the input shaft 111 and both planet wheels) , 190 are non-rotatably connected to the spindles 192, 193 by a hinge.

If the steering column 110 is rotated in one or the other direction of rotation, the planet wheels 189, 190 are driven and drive the threaded spindles 192, 193. Depending on the direction of rotation, both friction discs 181, 182 are then moved to the left or right of the roller 185. Thus, the friction disc 181 is pressed against the friction wheel 152 on the friction wheel 183 by a force equal to the size of the rotation of the column 110 control with respect to the input shaft 13 1. The friction wheel 183 drives with slip, which is dependent on the amount of thrust force, both friction discs 181 and 182 in the same direction in which the torque r and the steering column 1.10 are also transmitted. The torque that is transmitted to the friction discs 181, 101 translates through the pattern 12111 to the input shaft 111 of the steering gear.

In order to avoid too flexible steering when the servo-control is disabled, when the vehicle speed limit is exceeded, a centering device 160 'is provided, which provides a rigid connection between the steering column 56 and the input shaft 111 of the gearbox. The torsion bar rotating member 115 remains. The centering device 160 has a cup 195 that encloses the planetary gear 186 and is formed of a single piece with the sleeve 185. The edge of the cup 195 is provided with an axial toothing 16 into which a locking latch 197 which is mounted axially slidably and non-rotatably on the steering column 110 engages. . The locking z-hub 197 is in the region below the predetermined speed limit of the vehicle electrically disengageable, allowing the shaft 195 with the one-piece sleeve 185a fitted thereon with the sleeve 185 to rotatably connect the input shaft 11.11 the steering gear may rotate relative to the steering column 110. In addition to the locking pawl, an electrically actuated brake 188 may also be provided, as shown in FIG. 13 in the left half of the bowl195, in order to achieve a gradual insertion or support, for example, by means of a ramp brake control, when the vehicle reaches the specified speed limit. In the embodiment of the servo control according to FIG. 11, the excitation coils of the electromasses can also be arranged as fixed excitation coils in adjusting the corresponding structural changes. In such a case, it is necessary to modify the friction rings for the power supply.

Claims (49)

^ 1/32 ^ 2 '57 G 57 □ r?, 0,. \ T 0 6> N 61 PATENT CLAIMS A steering column steering vehicle steering apparatus with a steering column coupled to a steering column and an electric servo motor that provides a steering wheel underfloor torsional movement of a steering wheel, characterized in that that the servo motor (16) reverses that the steering column (10) and the steering gear input shaft (11) are connected to each other in a manner allowing only a limited relative rotation such that the sensor (40) detecting the relative rotation is proportional to the relative rotation a sensed signal that a control circuit (50) is provided which drives the servo motor (16) to output the torque as a function of the sensed signal, and is arranged in a force column between the output shaft of the servomotor (16) and the input shaft (11) of the gearbox. 10) a steering controlled two-way idle (20) which is designed to be rotatable of the steering column (10) against the input shaft (11) forms a rotatable connection between the output shaft of the actuator (16) and the input shaft (11) of the steering gear. 58 2. Power steering according to claim 1, characterized in that the idling (20) has a drive part (18, 19) connected to the output shaft of the electric motor (16), a driven part (22) connected by a steering gear shaft (11) and a control part (23), connected to the steering column (10), and that the idle (20) is formed such that the control part (23) forms such a non-rotatable part of the steering column during the pivoting movement of the steering column (10) 1, part (22), if the driving part (18, is faster than the steering part (23) following the column (10) of the steering 3. Power steering according to claim 2, characterized in that the drive part is formed by an outer ring (19) with an outer ring (18) which engages with the editor (17) driven by the output shaft of the servo motor (16). it is formed by a coaxial inner ring (22) which in turn is connected to the input shaft (11) of the gearbox, and at its circumference has a win (27) spaced apart from each other, each having a central section (27a) connected thereto. , the outwardly extending side sections (27b) and the steering portion having; does not rotate the rotational movement 59 on the one hand by the rollers (26) which are inserted into the middle sections (27a) and which support the inner ring (22) and the outer ring (19) and on the other hand the inner ring (22) and an outer ring (19) for coaxial steering (23) for guiding the rollers (26), which engages the two control arms (24, 25) in the circumferential direction forward of the rollers (26), 4. The steering gear according to claim 3, wherein the outer ring (19) with the outer ring (18) is formed by two parts in the radial direction and the two coaxial ring portions (19a, 19b) are connected to each other by a flexible insert. layer (28) «, 5. The steering gear of claim 4 wherein the surfaces of the two ring portions (19a, 19b) abutting the elastic intermediate layer (28) are coarse teeth. 6. A steering device according to claim 4 or 5, characterized in that elastic elements are provided in the region of the elastic intermediate layer (28, 69), for example spiral clamping pins (68) or leaf springs which engage both of them. the 6ϋ ring parts (19a, 19b) of the ring. 7. A power steering device according to one of claims 4 to 6, characterized in that the spring layer (28) has a ring shape. 8. The steering system according to one of claims 4 to 6, characterized in that the resilient layer (69) has a meander shape with sections (69a, G9b) arranged alternately in radial and circumferential directions. 9. Power steering according to claim 6, characterized in that the resilient elements (68) are arranged in radial sections (69a) of the resilient insert layer (69). 10. Power steering according to one of Claims 1 to 9, characterized in that the steering column (10) and the steering gear input shaft (11) are provided with a steering column (10) and a single shaft (1.1) connected in turn to the pootak the member (15; 115). 11. Power steering according to claim 10, characterized in that the steering column (10) and the steering gear input shaft (11) are disposed at one axis so that the pivot member (15) has an upright to the column 61 ( 10) steering and with respect to the steering gear input shaft (11) a co-axially bent ring (30) which is mounted on segments (31, 32) arranged adjacent to the circumferential direction with slotted pitch, so that non-adjacent segments (31 or 32) are held rotationally on the steering column (10), optionally on the input shaft (11). 12. Power steering device according to claim 11, characterized in that the bent ring (30) abuts the outer periphery of the segments (31, 32) at least in the middle region thereof, where it is clamped by the pressure plates (33, 34) screwed onto the segments (31). , 32). 13. A control device according to claim 12, wherein the dimensions of the pressure plates (33, 34) in the circumferential direction are substantially less than the dimensions of the segments (31, 32) and are supported in the circumferential direction of the press plates (33, 34). damping elements (36), for example rubber. 14. Servo drive according to claim 10, characterized in that the steering column (10) and the steering gear input shaft (11) are disposed in one axis and that the pivot member (115) is at least two in compressive springs (56, 57) acting in circumferential direction in pairs against time 62, which are adjusted relative to the axis of the steering column (10) and, in relation to the axis of the input shaft (11), are controlled diametrically opposite to the parallel axes of the compression springs (56, 57) and which are abutted on one side by a support portion (60) non-rotatably connected to the steering column (10) and on the other side by a support portion (61) fixedly connected to the input shaft (11). 15, the steering gear according to claim 14, wherein the disc supporting portions (oG, 61) are at least in the region of the helical compression springs (56, 57) of the camshaft and co-form the helical compression springs (56.57 ) in the direction of their length. 16. Power steering according to one of the points 14 or 15, characterized in that the compression springs (56, 57) are loaded onto the pins (56, 50), formed on the axle (6 G, 61), however, once the pins (56, 50) for receiving the springs (56, 57) belong to different carriers, there is a special printing of the parts (60, 61). z. points!; up to 16 17. A steering device according to claim 1, characterized in that a non-rotatably coupled support portion (60) and a coaxial inner ring (22) loosely coupled thereto between the outer edge (60a) formed by the cup and the column (10). (20) a damping ring (62) is inserted, for example from rubber. 18. Power steering according to one of claims 1 to 17, characterized in that the electric motor (16) is a DC motor with permanently energized magnets which is arranged in the bridge web (44a) of the bridge circuit (44) so that the bridge connection (44) has four controllable switches (51, 52, 53, 54; 63, 64, 65, 66) that in the bridge circuit (44) are always diagonally opposite switches (51, 52 or 53, 54; 63, 64, respectively) or 65, 66) are simultaneously set to on and off, and that the switch setting signal (51, 52, 53, 54; 63, 64, 65, 66) is discharged from the post rotation direction (16) ) management. A power steering device according to claim 18, characterized in that the switches are formed as controllable semiconductor switches (51, 52, 53, 54) such that the characteristic of the relative rotational direction is included in the sensor signal and that derives a switching signal for semiconductor switches (51, 52, 53, 54). 64 20. A power steering device according to claim 19, wherein one of the two semiconductor switches (51, 52, 53, 54) is set by a control circuit (50) with a keying ratio (t / T), determined by the sensor amplitude. -r signal. 21. A steering device according to claim 18, wherein the switches are formed as mechanically or electrically actuated switch contacts (63, 64, 65, 66) and a switching contact control device (70; 170) is provided. which, depending on the direction of relative rotation of the steering column (10) and the steering gear input shaft (11), switches at the same time two of the switching contacts (63, 64, or 65, 66) and in the zero position of each of the switching contacts (63, 64, 65 , 63) opens. 22. A steering device according to claim 21, wherein the switching contact actuator (70) has a threaded drive (71) having a spiral groove (72) disposed on the steering column (10) and an input shaft (11). ) of the gearbox is a non-rotatable but axially slidable guide (73) in which the guide pieces (75) with the balls (74) are pushed into the spiral groove (72) by means of the ring ring 65 (77) and thereby pivot the post ( 10) the steering gear and the input shaft (11) of the steering gear perform an axial displacement stroke, and the guide nut (73) carries the actuating member (80) for actuating the switching contacts (63, 64, 65, 66) " A power steering device according to claim 11 and 21, characterized in that the segments (31, 32) of the pivot member (15) are more curved at the outer periphery of the segments (31, 32), thereby forming between the segments of the segments (31, 32) the outer periphery of the segments (31, 32) and the bent ring (30) in the direction of the edge of the segments (31, 32) increase the radial air gap (91) so that the switching contacts control device (170) has at least one segments (32) connected non-rotatably to the steering gear input shaft (11), two in its peripheral region inserted, liquid-filled cushions (87, 88) that abut both sides in an axially displaceable piston (89) ) with a piston rod (30), and secondly, a plurality (87, SS) of a large surface plate (92) of a letter (89) which abuts the bent ring (30) by means of a plunger (93) of the piston plate (32) (89), but also a control member (94) for controlling the sp nacích KONR 66 bars (63, 64, 65, 66) which is connected sjpístnicí (90) of the piston (89) <> 24. A control device as claimed in any one of claims 21 to 23, wherein the closure contacts (63, 64, 65, 66) are formed by means of a locking pawl and each of the two control contacts (63, 64 and 65, respectively). 65) are combined in one microswitch (81, or 82), and the microswitches (81, 52) are arranged on both sides of the actuator (80) so that their switching pins (83, 84) engage the travel path of the actuator of the actuating member (80) and are actuated by the actuating member (80) in opposite displaceable movements. Servo control according to one of claims 21 to 23, characterized in that the switching contacts (63, 64, 65, 66) are formed by relay contacts and the two co-controlled relay contacts are combined into a single relay-controlled winding and provided with two outputs. A neck locating sensor (35), the movable part of which is provided on the actuating member (94). 26. Servo control according to one of Claims 21 to 25, characterized in that 67: i &lt; tb > &lt; tb &gt; &lt; / RTI &gt; (44) a conductor switch (67) is provided which is adjusted by a control connection (50) with a keying ratio (t / T) determined by the sensor signal amplitude value. 27. Power steering according to one of claims 1 to 26, characterized in that the sensor (40) is designed as an eddy current sensor having two counter-rotatable slit discs (41, 42) between which a sliding film is provided and a support plate (43). ) carrying the coils and that the support plate (43) is rigidly arranged and one slot disk (41) is non-rotatably connected to the steering column (10) and the second slot coil (42) is non-rotatably connected to the input shaft (11) steering gear. 28. Power steering according to one of claims 1 to 27, characterized in that a switching contact (45a) of the main relay (45) is arranged in series with the jumper web (44) and a speed detection device (48) is provided. a vehicle below the specified vehicle speed value generates a switching signal for the main relay (45). 29. Power steering according to claim 28, characterized in that an orifice 68 is provided (43) for detecting a gear that travels through the gearbox engaged in the first gear upward for forward or reverse gear. rearward or when the shift lever is detected in the neutral position, generates a switching signal for the main relay (45), and that the switching signals from the vehicle speed detection device (48) and the gear detection device (49) are logically coupled. or 23, characterized in that a sensor (55) of the keying ratio (t / T) is provided which produces a switching signal below a predetermined keying ratio (t / T) and that the sensor the signal is logically coupled to a switching signal of the vehicle speed detecting device (48). 31. Power steering according to one of clauses 28 to 80, characterized in that the control circuit (50) is on the inlet side connected to the orifices (18) for detecting the vehicle speed and not reaching or exceeding a predetermined value. The speed of the vehicle for activation or deployment sets the semiconductor switch (67) to a slower or non-cushioning rate to create an arbitrarily preset, increasing, non-decreasing torque moment with respect to time or speed. 32. A power steering according to the preamble of claim 1, wherein the steering column (110) and the steering gear input shaft (111) are connected to each other in a manner permitting only a limited relative rotation such that the steering device (114; 114; 114 ") for sensing relative rotation of the post (H?) Controlled by: and the steering gear input shaft (111) that the servomotor (116) runs at least below a predetermined vehicle speed in one direction that between the output a sliding clutch (112; 112; 112 ") arranged in both directions by the shaft (113) of the servo motor (116) and the steering gear input shaft (111), and that the sensing device (114; 114, '; 114") controls the slip clutch (112; 112; 112 ") such that it forms a clutch comert dependent on the relative rotation between the steering column (110) and the steering gear input shaft (111). 33. The power steering of claim 32, wherein the sliding couplers two in opposite directions of rotation driven clutch disks (112; 112 *; 112 ") are servomotors (.116) &apos; a clutch portion (120; 120) coupled to the steering gear input shaft (111) by means of a gear (121; 121), wherein the sensing device (114: 114) forms a relative rotation between the steering column (110) and the input shaft (lll) coupling, between the opposed clutch portion (120; 12θ ") and between one of the two clutch discs (118, 119) for rotatably driving it with a slope dependent on the relative rotation value. 34. A power steering device according to claim 33, wherein the opposite clutch portion (120) is selectively compatible with one or the other by at least two electromagnets (126) with excitation windings (127). a clutch disc (US, 119) and that the sensing device (114) has an electrical sensor, for example an eddy current sensor (14o), which provides an electrical output signal proportional to the relative rotation between the steering column (110) and the input shaft (111) a steering gear (150) which, depending on the output signal of the eddy current sensor (140), energizes the field winding (127) of the one or the other solenoid (126) with the drive current. 71 35. The power steering of claim 34, wherein the excitation windings (127) of the electromagnets (126) are arranged on the opposite clutch portion (120) and are coupled via friction contacts (128) to the control circuit (150). 36. A steering device according to claim 33, wherein the opposed coupling portion (120) is formed as an axially slidable reel (130) and the sensing means (114) is formed by a baffle unit (131, 132) that rotates the pivot (110). ) steering relative to the steering gear input shaft (111) for the axial displacement movement of the friction disc (130), which, in accordance with the direction of relative rotation between the steering column (110) and the input shaft (111), is a friction disc (130) into one or the opposite axial direction, and which presses it against one of the two clutch disks (118, 119) by a pressing force depending on the amount of relative rotation. A power steering device according to Claim 36, characterized in that the baffle unit has a threaded drive (131) and a high-pitch ball. 72 38. Power steering according to claim 37, characterized in that the actuator (131) is provided with two coaxial, drive-connected drive portions (133, 134) provided by the steering column (110) and provided by the steering gear input shaft (111). wherein the non-rotatable connection of one drive part (134) to the steering column (110) or to the input shaft (111) permits axial displacement such that it is rotatably connected to the axially displaceable drive part (134) and the friction disc (130) one sliding sleeve (130, 137) having a fixed connection in the axial direction, and that the double-arm displacement sleeve (132), the pivot axis (138) of which is disposed upstream of the drive portion (134) of the drive and friction coil (130), the two lever ends are engaged with the sliding sleeves (136, 137), 39. Power steering according to any one of claims 33 to 37, characterized in that the clutch disks (118, 119) and the opposite clutch portion are aligned coaxially and the two clutch disks (118, 119) are coupled via a reversing clutch. (117). 40. The power steering device according to claim 39, 73, characterized in that one clutch disc (118) is non-rotatably connected to the output shaft (113) of the actuator (116) and that the gearing between the opposite clutch portion ( 120) and the steering gear input shaft (111) is formed as a two-stage pattern (12l "). 41. The power steering of claim 39, wherein the gear of the reversing device (117) is coupled non-rotatably to the output shaft (113) of the servo motor (116) and that the gear between; the opposite clutch portion (120) and the steering gear input shaft (111) is formed as a single stage pattern (121). 42. The control device according to claim 40, wherein the non-rotatable connection to the output shaft (113) of the actuator (116) is provided by a centrifugal force-controlled idling (139). the drive shaft of which is non-rotatably connected to the output shaft (113) of the actuator (116) and whose output shaft is non-rotatably connected to one of the clutch discs (118) or to the gearwheel of the reversing device (117). 43. Power steering according to claim 32, characterized in that, on the one hand, the slip clutch 74 (112 ") has two friction discs (181, 182) which are arranged at a fixed axial distance from each other and are arranged axially displaceably and are fixedly connected to one another and a servomotor (116) a driven friction wheel (183) having a smaller diameter due to the light axial distance between the two friction discs (181, 182) and which is disposed radially with respect to the shaft (181, 182) formed by the shaft (184) between the friction discs (181, 182), and the sensing device (1.14 ") is constituted by a baffle unit (186, 191) that changes the rotational movement of the steering column (110) relative to the steering gear input shaft (111) for axial sliding movement the friction discs (181, 182), which moves the reel rotors (181, 182) under the relative rotation between the steering column (110) and the steering gear input shaft (111) into one or the other axial direction, and which presses one of the friction discs (181, 182) with a pressing force depending on the magnitude of the relative rotation on the friction wheel (183). 44. The steering gear of claim 43, wherein the baffle unit has a planetary gear (186) with a crown gear (187), pinion gear (188) and planetary gear wheels (189, 190) and a new drive spooled) with the threaded spindles (192, 193) threaded parallel to the steering column (11) 75 and the spindle nut (194) screwable to the threaded spindle (192, 193) 187) is non-rotatably coupled to the steering gear input shaft (111) and the float wheels (189, 190) are non-rotatably connected to the threaded spindles (192, 13) 3 and the spindle nut (194) is coupled rotatably and axially to the friction discs (181, 182). (and 45. A power steering device according to Claim 43 or Claim 44, wherein a pattern (121 ') is provided between the friction discs (181, 182) and the steering transmission input shaft (111), particularly in the form of a planetary gear. 46. The steering system as claimed in claim 43, characterized in that a centrifugal force-controlled idling (139) is preferably provided between the servo motor (116) and the friction wheel (183) driven by the latter, the drive shaft of which is not rotatably connected to the output shaft (113) of the actuator (116) and to the output shaft (184) the friction wheel (183) is rotatably supported. 47. A power steering device according to claim 76, wherein between the steering column (110) and the steering gear input shaft (111), the centering device is arranged above the predetermined vehicle speed (s). 160, 160). A steering device according to claim 47, characterized in that the centering mouth (160) has a radially protruding stop (161) on both the steering column (110) and on the other hand it cooperates with the input shaft (the steering gear). a mechanism (162) having two two-arm swiveling levers (164, 165) with abutting jaws (171, 172) facing each other and two more distal ends of the two-arm swivel levers at abutment jaws (171, 172) (164, 165) articulated connecting rods (166, 167) rotatably mounted on their common hinge pin (168) by their more remote from the two-armed pivoting levers (164, 165), and one drive (163) for moving the articulated pin (168 ) supplying end positions, wherein in one end half-seat the contact jaws (171, 172) on both sides of the nanowell (161) and in the second end position are the jaws ζ171, 17 2) at a predetermined distance odn and r and κ v i, 161), 77 49. The power steering of claim 48, wherein the articulation mechanism (162) is configured such that, at one end position of the articulation pin (168), it engages the stopper (161) when the contacting jaws (171, 172) abut. the connecting rod (166, 167) of the dead center position, in which the thrust acting by the stop (161) on the dispensing jaw (171, 172), forms a semi-displacement force on this pivot pin (168). 50. A power steering device according to claim 48 or 49, characterized in that the drive (163) has a spindle (174) and a spindle nut (175) that can be screwed onto the spindle (174) and that the hinge pin (168) is via a spring (169) connected to the spindle nut (175). 51. A power steering device according to claim 42 or 46, characterized in that the freewheeling (139) has, on the one hand, an inner ring (145), non-rotatably coupled with axially extending axial grooves (149) disposed around the periphery thereof, with an outer ring (146) non-rotatably connected with its output shaft, and supporting bodies (147), 78 which support the clamping half in the axial grooves, between the inner ring (145) and the outer ring (146). in which the inner ring (145) and the outer ring (146) are non-rotatably connected to one another when the inner ring (145) rotates faster than the outer ring (146) and which passes into the idling position in which it is the inner ring (145) separated from the outer ring (146) if the outer ring (146) rotates faster than the inner ring (145), and that the inner ring (145) is aligned with the outer ring (145) řádána ods a control force cage (148) which, when the lower limit number of the inner ring (145) is not reached, moves the clamping bodies (147) from their clamping position to the idle position, 52. A power steering device according to claim 51, wherein centrifugal weights (151) are pivotably mounted on the inner ring (145) and are pulled by a spring (154) inwardly coupled to the control cage (148) for pivoting them. 53. Power steering. according to one of claims 32 to 52, characterized in that the steering column connection (110) and the steering gear input shaft (111) is provided by a torsion element, preferably a torsion or rotating rod (115), is non-rotatably connected on one side to the steering column (110) and on the other side to the steering gear input shaft (111). Represents: