EP3173056A1 - Auxiliary wheelchair steering device and wheelchair fitted with such device - Google Patents

Abstract

A biassing steering apparatus (10) for a wheelchair (100; 200) having two electrically driven wheels (104; 204), each of which is drivable by an electric drive means (1 06L, 106R), comprises a biasing frame (13) adapted thereto is to be coupled to the wheelchair (100; 200), and a wheel (14) steerable by means of a steering device (16, 50) and a bias steering device control means (30) adapted to drive means mounted on the wheelchair (106L, 106R; 206; 212). The bias steering device controller (30) determines the operating mode of the electric drive devices (106L, 106R) of the wheelchair (100) with respect to speed control and torque control. There is also a wheelchair combination (1) comprising a wheelchair (100; 200) with two electrically driven wheels (104; 204), each of which is drivable by an electric drive device (1 06L, 106R), and such a biasing steering device (10). provided.

Description

The present invention relates to a bias steering device for a wheelchair with drivable wheels and a wheelchair combination with such a bias steering device.

Wheelchairs for people with disabilities usually have two large, arranged in the forward direction rear drive wheels and two small, freely pivotable and forward in the forward direction arranged wheels, which are also called castors. The drive wheels are usually driven by hand via a gripping ring in manually driven wheelchairs. Alternatively, electrically driven drive wheels can be used. In addition, for example, from the DE 198 57 786 A1 , Drive wheels known which are designed as an auxiliary drive device, both an electric drive motor and a gripping ring for manual drive and additionally comprise a sensor which detects a manually introduced into the gripping drive force, and a control device, the electric drive motor as a function of size and Direction of the manually introduced into the grip ring driving force and an adjustable level of support for delivering a corresponding torque drives.

The freely pivoting castors ensure a high level of maneuverability, which is indispensable especially in so-called indoor operation, ie when the wheelchair is used in closed rooms. For outdoor operation, ie when operating outside of closed rooms and especially on uneven roads, On the other hand, the small castors are disadvantageous and make it impossible to operate the wheelchair even with relatively little unevenness. For example, small front wheels would dip into depressions from which they could not come out because of their small diameter limited ability to negotiate an obstacle, which then makes driving impossible.

For the so-called outdoor operation, therefore, special small vehicles with electric drive and larger, usually not freely pivotable, but steered front wheels have been developed. Such small vehicles are also referred to as scooters, but are, in particular because of their insufficient maneuverability, unsuitable for indoor use and therefore come for people with disabilities who rely on a wheelchair, only as a second wheelchair, that is in addition to one for indoor operation suitable wheelchair, into consideration.

Against this background, attempts have been made for a long time to provide a conventional, suitable for indoor use wheelchair with a removable accessory, which makes it possible to complement the designed for indoor operation wheelchair functionally so and that he for the outdoor operation is suitable.

As early as 1974, the DE 24 46 573 a pulling and guiding device which can be coupled to a wheelchair in such a way that, when coupled, the front small wheels of the wheelchair designed as freely pivotable castors are raised. This known pulling and guiding device has a motor-driven wheel which can be steered via a steering rod. The vehicle formed from such a coupled guide and the wheelchair is called a wheelchair team.

The technical concept outlined above has been used in practice for more than four decades and has been further developed to this day. Comparable traction devices for wheelchairs and corresponding unicycle wheelchair compartment are for example from the GB 2 124 985 A from 1982, the DE 200 07 793 U1 from the year 2000 and the DE 10 2007 015 851 A1 known from 2007.

A disadvantage of this technical concept is that the wheel load and thus the contact pressure of the drive wheel of the traction device compared to the total operating mass of the unicycle wheelchair combination are low, since the majority of this total operating mass is introduced by the person sitting in the wheelchair whose focus in operation much closer on the rear large wheels than on the driven front wheel. As a result, only a small drive torque can be transmitted via the traction wheel and the traction wheel is already spinning at moderate inclines and moderate acceleration.

The invention has for its object to provide an improved Vorspannlenkvorrichtung for a wheelchair and a wheelchair combination with such a bias steering device, in particular to solve the technical problem set out above.

To achieve this object, the Vorspannlenkvorrichtung for a wheelchair according to claim 1 and a wheelchair combination are provided with such Vorspannlenkvorrichtung according to the invention.

The biasing steering device according to the invention is designed so that the drive of the wheelchair, even if it is connected to the biasing steering device according to the invention to form a wheelchair combination according to the invention, can take place via the drive wheels of the wheelchair. Therefore, the preload steering apparatus of the present invention does not need to have a drive wheel itself, but has a bias steering apparatus controlling means adapted to communicate with the drive means mounted on the wheelchair.

By this fundamentally different technical approach, a wheelchair team of a commercially available indoor wheelchair and the biasing steering device according to the invention can be formed. This wheelchair combination gives the indoor wheelchair outdoor properties, makes the purchase of a separate outdoor wheelchair unnecessary, compared to the prior art, a significantly better traction of the drive wheels and thus allows significantly better handling characteristics. In addition, the biasing steering device according to the invention can be a considerably lower Have weight than the known from the prior art traction devices, especially if they themselves have no motor-driven drive wheel and thus no corresponding batteries for an electric motor. As a result, the docking process to the wheelchair is much easier, so that it can be performed without great effort from the wheelchair and a person with disabilities.

The biasing steering device according to the invention is thus not, as in the prior art, a traction device, since the drive via the wheels, preferably the rear wheels of the wheelchair takes place, with the biasing steering device according to the invention is connected to form a wheelchair combination according to the invention. However, the biasing steering device according to the invention is a guiding and steering device, which gives the wheelchair combination according to the invention excellent handling characteristics even on unpaved roads. The steerable wheel can be made so large that it ensures the desired off-road capability, not already in smaller wells so sinks that from these can not be driven out, and also larger bumps such as coarse debris or curbs can be overcome. In addition, the operation ensures, since only relatively large wheels, especially not the small castors, have ground contact, a good ride comfort. At the same time the drive provided by the electrically driven wheels of the wheelchair, especially when the electrically driven wheels are the rear wheels, ensures excellent traction, since the weight on the rear wheels portion of the total operating mass of the wheelchair combination consisting of the wheelchair, the Vorspannlenkvorrichtung and in person sitting in the wheelchair, is considerably larger than the proportion of the total operating mass of the wheelchair combination, which rests on the steerable wheel of the Vorspannlenkvorrichtung.

If this superior off-road capability is no longer needed, but the compactness and maneuverability of an indoor wheelchair, the Vorspannlenkvorrichtung can easily and easily decoupled and the still preferably on his rear wheels electrically powered wheelchair can be used in the usual way in the indoor mode. Due to the fact that the Vorspannlenkvorrichtung neither a Drive motor still has to accommodate appropriate energy storage such as batteries, the Abdockvorgang, that is, the uncoupling of the biasing steering device of the wheelchair, easily from the wheelchair itself can be made.

The biasing steering device according to the invention forms with the wheelchair to which it is coupled, a functional unit that goes well beyond the known from the prior art, purely mechanical coupling. The communication between the bias steering device controller and the drive device mounted on the wheelchair allows information regarding operator commands and their effects on the wheelchair drive devices to be communicated to and further processed by the bias steering device controller, such as certain steering commands. On the other hand, this communication also allows operating commands entered in the region of the steering device of the pretension steering device and their effects to be transmitted to the drive devices of the wheelchair. In both cases, a simple operation with excellent driving characteristics can be combined.

An embodiment of the invention according to the former case of the communication between the biasing steering device control device and the drive device mounted on the wheelchair, that is, the transmission of information regarding operation commands and their effects on the drive means of the wheelchair to the Vorspannlenkvorrichtung controller, for example, then when the biasing steering device is provided with a steering motor that informs about the rotational speeds of the wheelchair driven wheels to the Vorspannlenkvorrichtung control device and this controls the steering motor so that the steerable wheel of the Vorspannlenkvorrichtung is directed according to the rotational speeds of the driven wheels of the wheelchair.

If the two drivable rear wheels of the wheelchair rotate at the same speed during operation, this means that the wheelchair is traveling straight ahead. The same applies if the wheelchair is connected to the biasing steering device according to the invention to form a wheelchair combination according to the invention. Turn the Rear wheels, however, with different speeds, this leads to the wheelchair alone, but also in a wheelchair team, to cornering. The above-described embodiment, in which the respective rotational speed information of the drive wheels of the wheelchair is transmitted to the pretensioner steering apparatus control means, enables the pretensioner steering apparatus controller to calculate a corresponding steering angle for the steerable wheel of the pretensioner steering apparatus from these rotational speed differences and the known geometrical data of the wheelchair team and to control the steering motor so that this calculated steering angle is taken by the steerable wheel. The person sitting in the wheelchair or the wheelchair team can thus continue to drive and steer the wheelchair in the usual way on the drive wheels attached to the hand gripping rings. While, in the case of the wheelchair alone, that is, without coupled Vorspannlenkvorrichtung, the freely pivotable Castoren follow the predetermined by the speed ratio of the drive wheels direction, in the case of the described embodiment, a corresponding steering angle or steering angle by the steering motor, driven by the Vorspannlenkvorrichtung-control device is set ,

Particularly advantageous, this arrangement is when the wheelchair has auxiliary drive devices of the type described above, as for example in the DE 198 57 786 A1 are described.

In another embodiment of the invention, the biasing steering device comprises an operating device which is connected to the biasing steering device control device and adapted to transmit operating commands to an electric drive device of the wheelchair.

The electric drive device of the wheelchair has two electric drive motors, wherein a plurality of motor control devices may be provided on the wheelchair. It will be understood that the biasing steering device control means, both directly and depending on the embodiment of an activation of the attached to the wheelchair electric drive devices independently as well as in cooperation with corresponding motor control devices of the wheelchair can cause.

The electric drive device of the wheelchair can be provided in a variety of ways. A wheelchair that can be connected to the biasing steering device according to the invention for providing the wheelchair combination according to the invention, for example, both be designed as an electric wheelchair from the conception of a wheelchair as well as a manual in principle, that is not electric motor driven wheelchair, only by replacing the pure manually driven wheels with such wheels, which are provided with an electric hub motor, to an electric motor driven wheelchair is. Such an electric motor driven drive wheel with a hub motor, which can be mounted not only on a rigid running, but also on a folding wheelchair, is for example in the DE 41 27 257 A1 disclosed. Another such electric motor driven drive wheel with a hub motor is for example in the DE 199 49 405 C1 disclosed. All such drive wheels with hub motor including those as in the aforementioned DE 198 57 786 A1 described auxiliary drive device are drive wheels that make a wheelchair to an electric motor driven wheelchair in the context of the present invention, that is to a wheelchair with an electric drive device, which can be made by coupling the biasing steering device according to the invention to a wheelchair combination according to the invention.

In electrically powered wheelchairs are often used drive wheels with hub motors, for example, as disclosed in the above-mentioned documents. An electronic control device for controlling the hub motors therefore has to cause an activation of both motors in the case of two drive wheels and thus two hub motors. The Vorspannlenkvorrichtung control device of the biasing steering device according to the invention communicates in such a case with two engine control devices, namely each of a motor control device for a hub motor. With regard to the control or control of such electric drive wheels of a wheelchair, in particular two types of control are known, namely a so-called torque control and a so-called speed control.

In the usual constellation with two rear wheels of a wheelchair each driven via hub motors, a torque control causes both motors to output the same drive torque. Such a torque control is widespread especially in so-called brush motors. It has the consequence that both drive wheels, namely a left and a right drive wheel, build the same torque. However, if a one-sided disturbance occurs in such a torque control, in particular in the form of a one-sided obstacle, which is the case, for example, when one of the drive wheels travels over a rock or if it is driven on a transverse slope, then the same torque results on both sides the one-sided disturbance variable to a different speed. The wheelchair would thus not go straight, but drive on a curve. Correction must be made by a modified move command.

In contrast, a speed controller presets a specific setpoint speed, which follows the wheel rotation frequency. Disturbance variables of the type described above are thus already compensated in the way of this control. A corresponding controller increases the torque of the affected engine so that the target speed is maintained when a one-way obstacle occurs.

In the preload steering device according to the invention, the type of control of the electric motors of the wheelchair, with which the biasing steering device can be connected to provide the wheelchair combination according to the invention, is taken into account.

A speed control, when the Vorspannlenkvorrichtung is coupled, has the consequence that the wheelchair combination tends to go straight regardless of the steering operation, since the drive wheels rotate on both sides with the same Raddrehfrequenz while cornering the curve outer Wheel compared to the inside wheel must have a greater wheel rotation frequency, if slippage should be avoided. Such a tendency to understeer the wheelchair combination is counteracted by the fact that when coupling the Vorspannlenkvorrichtung to a wheelchair and this takes place the Vorspannlenkvorrichtung control device of the biasing steering device to a motor control device of the wheelchair, the operating mode of the motor control device of the wheelchair is changed from a speed control mode in a torque control mode, the control of the drive wheels of the wheelchair thus no longer takes place as a speed control, but as torque control. This can be realized, for example, in that the motor control device of the wheelchair recognizes this as a new participant of the system when connecting the Vorspannlenkvorrichtung, for example via an RS-485 bus, and switches to the torque control mode. The torque control then acts like an electric differential and allows without slip the speed differences arising during cornering between the inside of the curve and the outside of the curve.

On the other hand, if the wheelchair has a torque control, then this control can basically be maintained.

In certain embodiments of the invention Vorspannlenkvorrichtung and the wheelchair combination, however, may be provided in the coupled state of the Vorspannlenkvorrichtung on the wheelchair for the control of the drive wheels of the wheelchair speed control. Such a speed mode of the controller may be selected, for example, when the preload steering apparatus is provided with a steering angle sensor that detects a steering angle and transmits corresponding signals to the preload steering apparatus controller such that, optionally in cooperation with one or more corresponding motor controls of the wheelchair in that the outer drive wheel is controlled in such a way that it rotates at a specifically higher rotational speed than the inner drive wheel. This allows a particularly good driving stability can be achieved.

The operating device can, in particular in cooperation with the steering device, be designed according to the needs of the person who is to drive with the wheelchair team, and in particular according to the degree of disability of that person.

For persons to whom a steering operation corresponding to that of a bicycle, for example a tricycle bicycle, is possible, the steering device may comprise a handlebar. The steering of the wheelchair combination is in this case effected in a manner analogous to a bicycle by pivoting the handlebar. In such cases, the operating device may have a rotary handle which corresponds to a motorcycle throttle grip. By turning this knob, the torque or the speed of the drive wheels of the wheelchair can be controlled. The effective direction of the torque or the direction of rotation of the drive wheels can be selected by a switch. Such a switch can be arranged separately or be part of an operating element. Another embodiment may include a rotary handle having a distinct zero position, that is, a zero position in which the torque or the rotational speed of the drive wheels is zero, and in which, when the rotary handle is rotated beyond this zero position, the torque or the rotational speed the drive wheels, starting from zero, be increased in the opposite direction. If, in analogy to the usual interpretation of motorcycles, a rotation against the forward direction leads to forward travel, so then can cause a reverse rotation beyond the zero position, a reverse drive. The expression of the zero position, for example, by a locking element, which can be overcome only with noticeably increased force, or any other type of lock can be effected.

As an alternative to the embodiment described above, the operating device may also have a joystick. The functions may be similar to those in known cases of wheelchair control. Such controls in conjunction with a joystick are known both for operations by the person sitting in the wheelchair as well as those performed by escorts. In this case, there is the possibility of electrically forcibly controlling the steering operation as well perform. Even in such an embodiment, both the torque control of the electromotive drive and the speed control, in particular in conjunction with a steering angle sensor, can be used. In particular, in such an embodiment, but also in other embodiments, may be provided, optionally in addition to one or more from the outside acting on the wheels brakes, an active engine brake.

The operating device may have an operating element which is attached to the side of the wheelchair, and may have a joystick. It may also include a display device that displays information about speed, operation mode, state of charge of the batteries, and the like, and may include switches and controls, such as ON / OFF switch, operation mode switch, up / down switch, and the like.

If no joystick is needed because the person sitting in the wheelchair can steer via a handlebar, the control element can be mounted in the region of the handlebar, for example centrally on the handlebar itself or on a steering column.

The electrical connection between the Vorspannlenkvorrichtung and its components on the one hand and the wheelchair and its components, in particular the electric motor drive and the related motor control devices of the wheelchair, on the other hand, depending on the embodiment via cable, for example, with magnetic plugs or other connector types, and / or via Bluetooth respectively.

Mechanically, the coupling between a biasing frame of the Vorspannlenkvorrichtung and the wheelchair preferably via a quick coupling.

The invention will be further elucidated on the basis of embodiments with reference to the drawings.

• Fig. 1 eine erste perspektivische Darstellung einer Ausführungsform eines erfindungsgemäßen Rollstuhlgespanns, zusammengestellt durch einen Rollstuhl und eine angekoppelte Ausführungsform einer erfindungsgemäßen Vorspannlenkvorrichtung,
• Fig. 2 eine zweite perspektivische Darstellung der Ausführungsform gemäß Fig. 1,
• Fig. 3 eine dritte perspektivische Darstellung der Ausführungsform gemäß Fig. 1,
• Fig. 4 eine Darstellung der Ausführungsform gemäß Fig. 1 von oben,
• Fig. 5 ein schematisches Funktionsschaltbild der Ausführungsform gemäß Fig. 1,
• Fig. 6 eine perspektivische Darstellung eines weiteren Ausführungsbeispiels eines handelsüblichen Indoor-Rollstuhls, der mit einer Vorspannlenkvorrichtung zur Bildung eines Rollstuhlgespanns verbunden werden kann, und
• Fig. 7 ein schematisches Funktionsschaltbild der Ausführungsform eines Rollstuhlgespanns mit dem Rollstuhl gemäß Fig. 6.

In the drawings is

• Fig. 1 1 is a first perspective view of an embodiment of a wheelchair combination according to the invention, assembled by a wheelchair and a coupled embodiment of a biasing steering device according to the invention,
• Fig. 2 a second perspective view of the embodiment according to Fig. 1 .
• Fig. 3 a third perspective view of the embodiment according to Fig. 1 .
• Fig. 4 a representation of the embodiment according to Fig. 1 from above,
• Fig. 5 a schematic functional diagram of the embodiment according to Fig. 1 .
• Fig. 6 a perspective view of another embodiment of a commercial indoor wheelchair, which can be connected to a Vorspannlenkvorrichtung to form a wheelchair team, and
• Fig. 7 a schematic functional diagram of the embodiment of a wheelchair combination with the wheelchair according to Fig. 6 ,

That in the FIGS. 1 to 4 wheelchair combination 1 shown is assembled by coupling a Vorspannlenkvorrichtung 10 to a wheelchair 100. For the sake of clarity, the reference numerals used in the following description are not inserted in each individual representation.

The wheelchair 100 has a seat 101, a backrest 102, a wheelchair frame 103, two large drive wheels 104 arranged rearward in the forward drive direction, and two small runners 105, which are freely pivotable and arranged in the forward direction of travel, which are also called castors. The drive wheels 104 are each provided with an electric motor drive device 106L, 106R designed as a hub motor. The drive wheels 104 are detachably attached to the wheelchair frame via thru axles and torque supports (not shown). Seen in the forward direction of travel, the wheelchair 100 thus has a left drive means 106L and a right drive means 106R. In the illustrated embodiment, the left drive 106L and the right drive 106R each have an electric motor (not shown) Accumulator (not shown) and a motor controller 120L, 120R, wherein these components are combined in the respective hub units.

It is understood that those skilled in the art may also choose other engine configurations and engine arrangements.

When the wheelchair 100 is operated alone, that is, without a coupled biasing steering device, it can be steered by controlling the electric motor of the left driving device 106L and the electric motor of the right driving device 106R so that the respective driving wheels 104 rotate at different rotational speeds. The castors 105 contacting the ground in this operating state follow the drive due to their free pivotability. Corresponding movement commands can enter the person sitting in the wheelchair via an operating element 140. The control element 140 may comprise a joystick 141, the pivoting of which from a central zero position out through the respective direction and the extent of pivoting a ride of the wheelchair with the appropriate direction and speed result, as well as various other switches and buttons for other conceivable functions such as operating modes and the same. Information regarding operating modes and operating data such as driving speed, state of charge of the accumulator devices and the like can be displayed via a wheelchair display element 150.

The biasing steering apparatus 10 includes a biasing frame 13, a wheel 14 guided in a fork 11, which is steerable about a steering shaft 12 via a handlebar 16, a rotary handle 24 rotatably mounted at one end of the handlebar 16 and connected to a biasing steering apparatus controller 30 , and a biasing steering apparatus display member 25 disposed centrally on the handlebar 16 and also connected to the biasing steering apparatus controller 30. In this embodiment, the bias steering device controller 30 is disposed in the housing of the bias steering device display element 25. It is understood that this structural unit is not mandatory and that the biasing steering device control device 30 may alternatively be arranged separately and elsewhere.

Depending on the embodiment of the biasing steering device 10, a steering angle sensor 40 and an electric steering motor 50 may also be provided. The steering angle sensor 40 detects a steering angle, for example in the region of the steering axis 12, and is connected to the biasing steering device control device 30. The electric steering motor 50 is also connected to the bias steering device controller 30 and may cause the wheel 14 to assume a certain steering angle in accordance with a related drive signal from the bias steering device controller 30.

The bias steering device 10 may be coupled to the wheelchair 100. For this purpose, corresponding compatible elements of a coupling device (not shown) are provided on the pretensioning frame 13 and on the wheelchair frame 103.

If, as in the FIGS. 1 to 4 shown, the Vorspannlenkvorrichtung 10 is coupled to the wheelchair 100, the originally touching the ground Castoren 105 are lifted from the ground. The wheelchair combination 1 rests and thus travels only on the drive wheels 104 of the wheelchair 100 and the wheel 14 of the biasing steering device 10. A steering of the wheelchair combination 1 is thus possible via the wheel 14.

In this state is, as in Fig. 5 shown, the Vorspannlenkvorrichtung controller 30 with the motor controllers 120L, 120R connected. The connection can be realized via a cable 18 or also wirelessly, for example by Bluetooth. An activation of the drive devices 106L and 106R can then take place via the rotary handle 24. The functionality of the rotary handle 24 may in this case be chosen so that this from a stop in which the drive devices 106L and 106R donate no torque, with increasing rotation to the person sitting in the wheelchair person, according to the functionality of a motorcycle handle, an increasing Torque of the rotary handle causes. The direction of the torque, that is, the choice of the direction of travel forward or backward, can be selected via a corresponding switch (not shown).

In another embodiment, the rotary handle 24 beyond a zero position, which corresponds to the stop in the previously described embodiment, in a The opposite direction, that is, away from the person sitting in the wheelchair, be turned. This can be used to ensure that, when turning towards the person seated in the wheelchair, the vehicle moves forwards and, when it is rotated in the opposite direction, that is, away from the person sitting in the wheelchair, it is reversed beyond the zero position.

In such a case in which the person sitting in the wheelchair is able to place both their hands on the respective ends of the handlebar 16 and to actuate the rotary handle 24, the steering of the wheel 14 via the handlebar 16, that is through Manual pivoting of the handlebar 16, done. Depending on the embodiment, however, it is also possible to effect the steering of the wheel 14 via the steering motor 50 provided in such an embodiment. The operation is in this case via the joystick 141 and the control element 140.

Both the handlebar 16 and the steering motor 50 are a steering device in the context of the present invention.

Depending on the embodiment, the display of the operating data and the like via the Vorspannlenkvorrichtung display element 25, the wheelchair display element 150 or both display elements.

When the preload steering apparatus 10 is coupled to the wheelchair 100, the actuators 106L and 106R are driven via or in conjunction with the biasing steering apparatus controller 30. Various configurations and configurations are possible.

When the wheel 14 is steered via the handlebar 16 in the coupled state, the drive devices 106L, 106R are preferably operated in the torque mode, that is to say the operating mode of the torque control, since this acts as a differential and allows a cornering without slippage predetermined by the wheel 14. When the motor controllers 120L, 120R were adjusted before the coupling of the biasing steering device 10 so that the driving devices 106L, 106R operate in the speed mode, that is, the speed control operation mode, so The biasing steering device controller 30 detects this upon coupling and causes it to switch to the torque mode.

Alternatively, there is a possibility that the speed mode is maintained. In such a case, by means of the steering angle sensor 40, the steering angle of the wheel 14 can be detected and, based on this, the drive of the drive devices 106L, 106R be made so that the speed difference between the inside and the outside wheel is taken into account.

The above-described activation of the drive devices 106 L, 106 R is also possible when the wheel 14 is effected via the steering motor 50.

The biasing steering device controller 30 is typically composed of a semiconductor integrated circuit including, for example, a central processing unit (CPU), a ROM storing one or more programs, and a RAM serving as a desktop. However, certain programs or even physical elements may already be provided on the wheelchair 100, but are only activated when the biasing steering device 10 is coupled to the wheelchair 100 to form the wheelchair combination 1.

A wheelchair 200 as a further embodiment of a commercially available indoor wheelchair, which can be connected to the biasing steering device according to the invention to form a wheelchair combination according to the invention, is in Fig. 6 shown. Fig. 7 shows a schematic functional diagram of the embodiment of a wheelchair combination according to the invention with a commercial indoor wheelchair 200 according to Fig. 6 ,

Basically, such a wheelchair combination corresponds to that in the FIGS. 1 to 4 is shown. In that regard, a new description of identical or substantially functionally identical features and components is omitted.

One difference is in the nature of the drive of the rear wheels 204. These each have a hand gripping ring 212, via which a person sitting in a wheelchair person respective rear drive wheel 204 of the wheelchair 200 in a known manner manually, that is, by hand, can drive. A steering operation takes place in this wheelchair 200 in that the two drive wheels 204 a different speed is impressed. The rear wheels 204 of the wheelchair 200 which can be driven via the gripping rings 212 are thus drivable wheels in the sense of the invention, and the gripping rings 212 are both an operating device and a drive device in the sense of the invention.

When such a wheelchair 200 is connected to a preload steering apparatus 10 according to the invention to form a wheelchair combination 1 according to the invention, the rotational speed of the drive wheels 204 must be detected to drive the preload steering apparatus control means 30. This is possible via corresponding sensors (not shown). Signals from these sensors, which contain information about the respective speeds, both in terms of magnitude and direction, are transmitted to the biasing steering device controller 30. This represents a communication of the biasing steering device control device 30 with a drive device 212 mounted on the wheelchair.

Based on the signals corresponding to the rotational speed and the direction of rotation of the drive wheels 204, the bias steering device controller 30 controls the steering motor 50 so that the steerable wheel 14 of the bias steering device 10 assumes a corresponding steering angle. The steerable wheel 14 of the biasing steering apparatus 10 is thus positively controlled by the biasing steering apparatus controller 30 and the steering motor 50 so that the wheelchair team 1 follows the direction predetermined by the manual drive of the rear drive wheels 204 via the handgrip rings 212.

Such a wheelchair combination 1 can therefore, as well as in Fig. 6 shown wheelchair 200, alone on the drivable rear wheels 204 are steered. At the same time, however, such a wheelchair combination offers superior handling characteristics in outdoor operation by virtue of the fact that the wheel 14 of the pretensioning steering device 10, which is larger than and also positively deflected in relation to the castors.

In the Fig. 6 illustrated embodiment of the wheelchair 200 has drive wheels 204, in addition to the hand gripping rings 212 additionally designed as an auxiliary drive drive means 206, as shown for example in the DE 198 57 786 A1 is disclosed. Each drive wheel 204 has a hub 211 which is connected by means of commercial spokes 217 with a rim 218 on which a tire 219 is mounted. Inside the hub 211, there are disposed a drive motor configured as an electric motor (not shown), a rechargeable battery (not shown), and a motor controller 220L, 220R.

The hand gripping ring 212 is connected to the rim 218 via three struts 213 and three spoke elements 214.

When a manual force is introduced into the handgrip ring 212, it is transmitted via the struts 213 and the spoke elements 214 directly to the rim 218. A sensor means (not shown) disposed between the strut 213 and the spoke member 214 detects the action of the force acting on a spoke member 214. This effect is, on the one hand, a stress generated in the spoke element 214 and, on the other hand, a deformation of the spoke element. At least one of these effects is detected in each case and serves as a measure of the force introduced into the gripping ring 212. According to this measure, the drive motor of the respective drive means 206 is driven by the motor control means 220L, 220R to provide a torque. In this case, variable or permanently preprogrammed degrees of support can be provided.

Suitable such sensor devices or sensors are for example in the EP 0 945 113 A2 disclosed.

The operation of this embodiment of the wheelchair combination by a person sitting in the wheelchair person corresponds to that of the previously described embodiment with purely manually driven rear wheels 204, but also offers the advantage that higher driving performance are possible by the electromotive assistance. With regard to the technical implementation offers the The latter embodiment also has the advantage that separate speed sensors for the rear wheels 204 are generally not required, since the speed information can be tapped from the motor control means 220L, 220R of the drive means 206.

It will be appreciated that the provision and manner of mounting other components such as a handlebar 16 or a biasing steering device indicator 25 may be selected by those skilled in the art, depending on the design and requirement profile.

It is also understood that the number of driven wheels of the wheelchair and thus the wheelchair combination as well as the number of steered wheels of the biasing steering device are not limited to the embodiments shown in the figures.

Claims (12)

A power steering apparatus (10) for a wheelchair (100; 200) having two electrically driven wheels (104; 204), each of which is drivable by electric drive means (106L, 106R), comprising: a biasing frame (13) adapted to be coupled to the wheelchair (100; 200), and a by means of a steering device (16, 50) steerable wheel (14), and a pretensioner steering control means (30) adapted to communicate with a drive means (106L, 106R; 206; 212) mounted on the wheelchair; characterized, in that the biasing steering device control device (30) determines the operating mode of the electric drive devices (106L, 106R) of the wheelchair (100) with respect to speed control and torque control. A toe steering apparatus according to claim 1, characterized in that the biasing steering device control means (30) sets the operating mode of the electric drive means (106L, 106R) of the wheelchair (100) when in the speed control mode prior to docking so that it is in the coupled state in the mode of torque control is. A preload steering apparatus according to claim 1, characterized in that the steering means comprises a steering angle sensor (40), detects the steering angle and transmits corresponding signals to the Vorspannlenkvorrichtung control device (30), and that the Vorspannlenkvorrichtung control means (30) determines the operating mode of the electric drive means (106L, 106R) of the wheelchair (100) to be in the mode of the speed control in the coupled state,
wherein biasing steering device control means (30) based on the obtained from the steering angle sensor (40), the steering angle signals, the outside drive wheel is driven so that it rotates at a deliberately higher rotational speed than the inside drive wheel. Tension steering device according to one of the preceding claims, characterized in that the steering device has a steering motor (50). A preload steering apparatus according to claim 4, characterized in that the communication between said bias steering apparatus control means (30) and said wheel mounted drive means (106L, 106R; 206; 212) includes information regarding the rotational speeds of said wheelchair driveable wheels (104; 204). 100; 200) and the steering motor (50) is controllable such that the steerable wheel (14) is steered according to the rotational speeds of the drivable wheels (104; 204) of the wheelchair (100; 200). A preload steering apparatus according to any one of the preceding claims, characterized in that an operating device (24, 140, 141) is connected to the preload steering apparatus control means (30) and adapted to supply operating commands to the electric drive means (106L, 106R) of the wheelchair (100) to transfer. Tensioning steering device according to claim 4, as far as this one of the preceding claims 1 to 3 is referred back, characterized in that the steering device comprises a handlebar (16). Tension steering device according to claim 7, characterized in that on the handlebar (16) a rotary handle (24) is arranged and that the electrical Drive device (106L, 106R) of the wheelchair (100) via the rotary handle (24) is controllable. Tension steering device according to claim 8, characterized in that the rotary handle (24) has a zero position in which the electric drive means (106L, 106R) of the wheelchair (100) is controlled so that the torque and / or the rotational speed of one of the electric drive means (106L, 106R) driven drive wheel (104) of the wheelchair (100) is zero. A wheelchair combination (1) comprising a wheelchair (100; 200) having drive means (106L, 106R; 206; 212) and a biasing steering apparatus (10) according to any one of the preceding claims. Wheelchair combination (1) according to claim 10, characterized in that the drivable wheels (204) of the wheelchair (200) have a hand gripping ring (212) over which they can be driven by hand, and an electric drive means (206) serving as auxiliary drive means is designed and emits an additional drive torque in response to an introduced into the hand gripping ring (212) torque. Wheelchair combination (1) according to claim 10, characterized in that the operating device has a joystick (141) and that the steering motor (50) and / or an electric drive device (106L, 106R) of the wheelchair (100) via the joystick (141) controllable is.

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