DE102015202924A1 - Drive device for a sliding carriage, in particular a Schiebe Gehhilfe - Google Patents

Abstract

Drive device for a sliding carriage, in particular a sliding walker, comprising a wheel hub motor (10) with a rotor (11) and a stator (12), wherein the rotor (11) is connected to an impeller (4) to be driven, and the stator (12) is arranged on an axle (13) which on one or both sides of the wheel hub motor (10) for connection to a suspension (9) of the sliding carriage (1) protrudes, wherein the motor side at least one sensor (18) for detecting a measure of a on the push carriage (1) applied thrust force representing information on the axis (13) and a the operation of the wheel hub motor (10) in response to the detected information controlling control device (17) is provided.

Description

The invention relates to a drive device for a sliding carriage, in particular a Schiebe Gehhilfe.

In many areas of daily life, pushcars are used, which serve different purposes. They may be transport aids, such as a wheelbarrow, a baggage car or a stroller, or walkers, so-called rollators, which are used by elderly or disabled people. Such a sliding carriage in the form of a walker is for example made DE 20 2012 001 457 U1 known. This sliding carriage or walker has several wheels, of which at least one is driven by an electric motor. To control the electromotive drive sensors are provided on the handle side, via which the hand pressure, the person exerts on the support handle, is measured, this signal is used to control the torque of the electric motor drive element. Via the electromotive drive, the sliding movement can be supported, that is, the forward drive is actively supported by the electric motor. The higher the contact pressure, the higher the torque of the drive motors. This makes it possible, in particular, any underground resistance such. B. cobblestone or a rising path that requires a higher pushing force on the part of the person to be able to overcome.

Although such sliding carriage or rollators are advantageous for the user, they are nevertheless elaborately constructed. Thus, corresponding sensors are to be integrated in the area of the support handles and connected to a control device which controls the electric motor.

The invention is thus based on the problem, a contrast improved drive means for a sliding carriage, in particular a Schiebegehhilfe indicate.

To solve this problem according to the invention a drive device for a sliding carriage, in particular a Schiebe Gehhilfe provided, comprising a wheel hub motor with a rotor and a stator, wherein the rotor is connected to an impeller to be driven, and the stator is arranged on an axis, the one or protrudes on both sides of the wheel hub motor for connection to a suspension of the sliding carriage, wherein the motor side at least one sensor for detecting a measure of a force exerted on the sliding carriage pushing force representing information on the axis and the operation of the wheel hub motor in response to the detected information controlling control device is provided ,

The inventively provided drive device is characterized by a compact design and includes all relevant components that are needed for adaptive support in the context of the use of such a sliding carriage. The drive device has a wheel hub motor, comprising a rotor and a stator. The rotor is directly connected to the impeller to be driven, that is, the impeller preferably sits directly on the rotor, so that a rotor movement leads directly to an impeller movement. The stator, on the other hand, sits on an axis that represents the interface to the carriage frame. The axle protrudes on one or both sides of the wheel hub motor, so stands out from the outside and allows easy connection with a corresponding suspension of the sliding carriage.

Furthermore, at least one sensor is provided on the motor side via which the thrust force exerted on the sliding carriage or a measure thereof is ultimately detected. The sensor acquires the information or its measurement signal directly on the axis. The corresponding sensor signal is given to a control device, which is also integrated, and which evaluates the sensor information and controls the operation of the wheel hub motor accordingly.

The drive device according to the invention is thus designed as a compact device with all the required operating components. It is due to the arrangement of the axle mounted in a simple manner, that is, that the axle is to be fastened only in the suspension of the sliding carriage, about which the drive means is mounted. This also makes it particularly advantageous to install the drive device as a retrofittable device on sliding carriage or in particular walking aids, which did not previously have an electric motor support. It is merely a previous, non-driven wheel against the drive device, which has an impeller itself as described, replace. The axis of the drive device is designed and integrated via fastening means according to the sliding carriage frame respectively the local suspension, so that a retrofit is possible in a simple manner.

Due to the integration of all relevant operating elements, in particular the at least one sensor and the control device, a mounting of these elements in other positions, as usual in the prior art, is not required.

The sensor itself is designed either for measuring a bend or for measuring a torsion of the axis. As described, the sensor picks up the measurement signal directly at the axis. Depending on the operating situation, the axle is loaded accordingly. If, for example, there is background unevenness, then the user must inevitably press a little more strongly against the sliding carriage in order to drive over the unevenness. This increased thrust force results directly in a bending stress of the flexurally soft axis, so that the sensor can detect a corresponding, resulting from a bend signal. For this purpose, at least one corresponding strain gauge is preferably arranged on the axis, which senses a corresponding bend, no matter how small.

Alternatively, a torsion measurement can be done. Depending on the user thrust, the torque on the axle changes, and consequently the detected torsion. This torsion is also preferably detected by means of a strain gauge arranged on the axle. Regardless of whether a bend or a torsion is detected, the corresponding sensor signal is given directly to the control device, which then performs the control of the wheel hub motor depending on the measurement signal.

As an alternative to measuring a bend or torsion, it is also conceivable to use as sensor a pressure measuring sensor which is arranged on the axle in the region to be arranged in the wheel suspension. For example, if the suspension is fork-shaped and the axle protrudes on both sides, then the axle can for example be firmly clamped on one side, so that it is rotationally fixed to the wheel suspension and thus to the carriage frame. In the region of the second connection point to the wheel suspension, a pressure measuring sensor is arranged, which detects the pressure given there, which of course changes depending on the surrounding situation. As such a sensor, a tension-pressure sensor or, for example, a piezoelectric film sensor may be used.

According to an expedient development of the invention, a sensor for detecting a measure of the acceleration representing acceleration information may be provided, wherein the control device is designed to control the operation of the wheel hub motor in response to the acceleration information. If an acceleration is detected via this acceleration sensor, even if it is very low, then a user request for a locomotion can be determined from this. If, however, even the slightest acceleration is detected after a standstill, this can be immediately processed by the control device as a signal that the carriage is actively pushed, and therefore also a sliding support on the part of the wheel hub motor is required.

Depending on the detected acceleration, a different control is possible. If a positive acceleration detected, so therefore a pushing or accelerating the sliding carriage, this signal is converted into an increase of the motor current to generate a corresponding torque, that is, the wheel hub motor actively drives the wheel on respectively accelerates it. However, if a negative acceleration detected, thus a braking pulse, so this leads to a reduction of the motor current, that is, that the wheel hub motor actively brakes the pushcart.

Particularly advantageous is the acceleration detection in the case when the user stumbles, so it comes to an unwanted, very strong acceleration. Here, the control device can intervene again supportive. As soon as, for example, a previously set acceleration threshold value is exceeded by the signal detected by the sensor, this is an indication that there is an unintentionally strong acceleration, for example tripping. Hereupon, the control device controls the wheel hub motor so that it brakes the pushcart immediately and the pushcart on the one hand no longer rolls off, and on the other hand can be used in particular by the user for supporting, so that he can thereby possibly prevent a final fall. Over this an additional adaptation of the electromotive drive to the actual situation can be achieved.

Furthermore, it is expedient to provide a sensor for detecting a location information describing the spatial position of the wheel hub motor, wherein the control device is designed to control the wheel hub motor in dependence on the position information. From the detection of the spatial position of the wheel hub motor respectively the drive means, and thus in the final consequence of the carriage frame, it can be determined whether the sliding carriage is horizontal, ie on a plane, or if it is on a slope, so it goes uphill, or if one Downhill is traveled. If the situation is known, the wheel hub motor can in turn be controlled accordingly by the control device and the engine torque can be adjusted accordingly, so that the degree of support can be better adapted to the actual situation.

Particularly preferred is a 3-axis sensor is provided, which can serve as an acceleration sensor and / or as a position sensor.

Finally, it is expedient if a sensor for detecting the rotational speed of the rotor is provided, wherein the control device is designed to control the wheel hub motor as a function of the rotational speed. If the rotor speed and thus also the impeller speed is detected, a constant speed control can take place if neither braking nor acceleration is detected. The drive means operates in this case so speed controlled. Between an operation that takes place as a function of a detected acceleration or braking pulse, and a speed-controlled, ie constant operation, can be easily switched.

As such a speed sensor, for example, a light barrier sensor may be provided, alternatively, a Hall sensor can be used.

The inventive, quasi-modular drive device that can be installed as a single component on the sliding carriage, allows for easy integration. Since all relevant components are provided, no additional elements to be installed on the sliding carriage, in particular, no sensors must be installed in the grip area. The number of interfaces and the required design effort for the manufacturer of the sliding carriage, especially the rollator, therefore reduced. The detection of all relevant information to be based on the control takes place directly in the drive device, wherein in addition to the provision of thrust assistance it is possible by installing additional sensors such as acceleration sensor, position sensor or speed sensor to realize a very flexible adaptive support operation. Since the control device is already part of the drive device, this can be programmed accordingly, in addition to z. B. the fall detection and fall avoidance possibly to implement other possible safety features, such as an automatic emergency call in case of a fall, which can be detected for example via the acceleration sensor, an anti-theft device, a record of movement profiles, user recognition, which are derived from the movement or sliding profile can, a rollaway and the like. A supported cornering is possible with a sliding carriage comprising two drive devices according to the invention. For this purpose, a sensor is provided on the carriage side, e.g. a gyrometer with which a rotation about the vertical axis can be detected. If this is the case, where are the two wheel hub motors driven accordingly different and support or simplify the cornering (differential function). With the differential function or the different control of the two motors, the handling of the sliding carriage compared to a wheel-synchronous motor control is further improved.

Also, a distance control can be done, so always a defined target distance between the user and the sliding carriage are adjusted, which is kept constant. If the user wants to start, he goes to the pushcart, so z. B. the rollator, so that it accelerates and the target distance is restored. When braking to slow down or stop, the distance between the user and the car increases, so that the engine is downshifted and brakes again. The user identification is carried out here via the evaluation of the acceleration signal. For distance measurement and one or more sensors, for. B. ultrasonic sensors, which are mounted on the frame and detect the legs of the user, be provided.

In this case, the system can be designed so that the user must always provide a portion of the driving force itself, with changes in this user power can always be detected due to the resulting change in the deformation of the bending or torsionally soft axle and a rapid adjustment of the engine torque over the Lead control device. The zuzuschaltende engine torque is transmitted by the controller on the basis of the size of the deformation and, if provided, preferably the amount of acceleration. Slopes and downhill gradients are also recorded by means of the optional built-in position sensor so that the degree of support or the engine torque can still be adjusted to this effect.

Only a power supply in the form of a suitable accumulator is installed on the sliding carriage frame at a suitable position. Otherwise, only a drive device is to be mounted in the manner described, wherein, of course, preferably two such drive devices are mounted instead of the two non-steered rear wheels.

The invention will be explained below with reference to an embodiment with reference to the drawings. The drawings are schematic representations and show:

1 a perspective view in the form of a schematic diagram of a sliding carriage in the form of a walker with two driving devices according to the invention provided thereon,

2 a schematic representation in section of a drive device according to the invention, mounted on a suspension of a sliding carriage, and

3 a diagram illustrating a waveform of an acceleration signal.

1 shows in the form of a schematic diagram of a sliding carriage 1 in the form of a walker, also called rollator. The sliding carriage 1 has a cart frame 2 on, on the two steerable front wheels 3 and two rear, rigid wheels 4 are provided. About a push handle 5 can a person 6 the pushcart 1 grab and push.

The wheels 4 are actively drivable and part each of a drive device 7 of which each, as will be discussed below, has a wheel hub motor and allows the sliding carriage 1 actively driving or braking. An energy supply is planned 8th in the manner not shown in detail with the drive means 7 connected and allows the operation of the wheel hub motors.

The drive device 7 is in each case at corresponding wheel suspensions 9 , which is provided on the frame side, attached. The drive devices 7 can either switch on automatically, as soon as a movement of the sliding carriage 1 is captured, which will be discussed below. This means that at standstill, they go into a kind of standby state and immediately become active again when a movement is detected. Alternatively, there is the possibility that the user drives the drive 7 also via a switching element, which is not shown here in detail, and for example in the area of the push handles 5 is arranged, or a remote control switches on.

2 shows in the form of a sectional schematic representation of a view of one of the compact drive means 7 in their arrangement in the corresponding suspension 9 , The suspension 9 is executed in the example shown in the manner of a U-bracket.

The drive device shown cut open 7 has a wheel hub motor 10 on, comprising a rotor 11 with which immediately the impeller 4 connected is. Also provided is a stator 12 that stuck on an axis 13 sitting. The axis 13 is on both sides of the wheel hub motor 10 off to the side. She reaches through the suspension 9 in appropriate openings 14 and is via appropriate fastening nuts 15 firmly on the wheel suspension 9 screwed.

Inside a side panel 16 that the wheel hub motor 10 is largely included, is a control device 17 arranged, which controls the motor operation, that controls its energization accordingly, and about the engine torque adjusts accordingly. The wheel hub motor 10 is as described on the power supply 8th , So a suitable accumulator operated. The control device 17 can adapt the supplied motor current and thus the generated motor torque of the corresponding situation, which will be discussed below.

At the axis 13 in the example shown on both sides in each case a sensor 18 applied in the form of a strain gauge. This sensor 18 The purpose of this is to allow for any bending or torsion, depending on which parameter is detected, of the otherwise flexurally or torsionally soft axis 13 capture. About this detected information or the corresponding signal, the force is determined, the user on the sliding carriage 1 exercises. For example, are the two front wheels 3 rolled against a bump or obstacle, so the user must 6 Press strongly to roll over this obstacle. This pressure or this thrust leads to a naturally extremely low bending or torsion of the axis 13 , however, about the one or more sensors 18 (It's just a sensor too 18 usable) and to the control device 17 is given, which evaluates the corresponding signal. Depending on this determined thrust the control device 17 the wheel hub motor 10 accordingly trigger, to generate a higher support torque, so therefore the sliding carriage 1 to drive in a correspondingly greater extent so that the user 6 without much effort the obstacle can roll over.

Furthermore, a combined acceleration and position sensor is provided 19 , About this sensor 19 , which is designed as a 3-axis sensor, on the one hand, the acceleration can be measured, the sliding carriage 1 experienced by the user. Is the pushcart 1 and pushes the user 6 the sliding carriage, so the sensor detects 19 this immediately. For example, then as described the connection of the drive devices 7 respectively the control device 17 take place, but in any case, the control device 17 based on this acceleration signal and optionally in conjunction with a signal from one of the sensors 18 Determine if and how much support for the wheel hub motors 10 is required.

A closer look at the function of the acceleration sensor follows in conjunction with 3 ,

The sensor 19 also serves to make a position detection, so therefore to determine what spatial position of the drive device and thus the carriage frame 2 Has. This can be used to determine whether a rising slope, a sloping slope or a plane is being used. Depending on you can a stronger support (in the case of a descending slope) or a braking torque (in the case of a gradient) to be produced. The control device 17 now determines the spatial position due to the sensor signal and can turn the operation of the wheel hub motor 10 control accordingly. Instead of a combined acceleration and position sensor and two separate sensors can be provided.

Finally, a speed sensor 20 provided over which determines the rotor speed or the axle speed and to the control device 17 can be given. Such a sensor may, for. B. be designed as a light barrier sensor or as a Hall sensor. For example, has the sensor 19 indicated that a level is traveled, and if no acceleration is detected, so a speed-controlled operation can take place, that is, that the control device 17 the rotor speed keeps constant, so therefore a constant support is given.

All components are visible on or within the drive device 7 installed. This is only on the suspension 9 fasten in the manner described and with the power supply 8th to couple via a corresponding cable connection, after which the operation can be immediately recorded. Also retrofitting a rollator is by simply replacing the original, non-driven rear wheels with drive devices 7 the type described possible.

3 shows in the form of a diagram a course of an acceleration signal 21 as it is about the sensor 19 can be measured. The time t is plotted along the abscissa, along the ordinate the respective acceleration value a. At the beginning of the waveform shown, the acceleration signal increases 21 Relatively strong, there is a positive acceleration, that is, the user 6 The sliding carriage actively pushes forward and accelerates, see the section I , When a first threshold value S _{1 is} exceeded by the acceleration signal 21 detects the control device 17 that support is needed and increases according to the motor current, so that the respective hub motor 10 generates a higher torque and thus actively drives forward. Then the acceleration signal decreases again. Below the threshold value S ₁ , the active assistance is canceled by a higher torque. It turns an area II one in which the acceleration is almost zero, that is, is pushed at a constant speed. In this case, the controller switches 17 in a speed-controlled operation order, that is, based on the continuous across the sensor 20 Controlled speed, the aim being to support with a constant rotor speed.

Subsequently, a strong negative acceleration sets in, see the section III , This means that the user brakes the pushcart heavily. When a threshold value S _{2 is} exceeded, the control device recognizes 17 in that brake assistance is required and correspondingly reduces the motor current, so that virtually a braking torque starts. Then the signal edge drops steeply again, it turns an area IV in which again a speed-based control is given.

Then, see the diagram, the acceleration signal increases 21 again extremely strong and exceeds a threshold S ₃ , see the area V , This extreme forward acceleration is an indication that there may be a fall. When the threshold value S _{3 is} exceeded, the control device recognizes this 17 and controls the wheel hub motor 10 immediately so that it slows down immediately. It is thus actively opposed to a high braking torque, which sometimes allows the user to still lean on the sliding carriage and prevent a fall. Inevitably, this takes the acceleration signal 21 again strong.

About the sensor 19 is therefore very precisely an acceleration detectable, which can be used as the basis for the control. This possibly also in conjunction with a position information, via the sensor 19 can be detected. For it follows that, for example, a downhill course is traveled, it is naturally a slightly stronger acceleration when pushing. This can be taken into account in the context of the control of the respective wheel hub motor in order to ensure the most comfortable possible support operation.

Furthermore, sensors, for. B. ultrasonic sensors, be provided for detecting the actual distance of the user to the sliding carriage. Then a combination of acceleration detection and distance control is possible.

The drive system consists of two wheel hub motors and a power supply and measuring unit. The measuring unit must be positioned so that the user's legs are within the detection range of the ultrasonic sensors.

The combination of acceleration detection and distance control enables constant driving and user recognition without additional sensors and other interfaces. The activation of the drive system requires a release criterion, which consists of two signals. The first criterion is the setting of an initial distance of the user during operation. The second criterion is an acceleration pulse of the user, which must exceed a set threshold. Due to the passage of the user, this reduces its distance to the attached measuring unit, this change in distance is used as a control variable of the motor drive. If the user reduces his or her distance, the engines are braked. The release criterion for the driving operation is withdrawn after a certain time at standstill. A renewed activation of the driving operation is possible by reapplying an acceleration pulse.

If the user applies a negative acceleration impulse, the shunting mode is activated. This means that the motors are switched to freewheeling operation and thus maneuvering is possible. During the shunting operation, the user can be given an acoustic or visual feedback.

By using an acceleration and yaw rate sensor, it is possible to identify slopes and thus brake in declines or adjust the slopes.

The fall detection also takes place with two criteria, namely an acceleration pulse and a high value of the controlled variable. When this criterion is met, braking will be initiated.

LIST OF REFERENCE NUMBERS

1

 Schiebewagen

2

 carriage frame

3

 Wheel

4

 Wheel

5

 push handle

6

 person

7

 driving means

8th

 power supply

9

 Arm

10

 hub motor

11

 rotor

12

 stator

13

 axis

14

 perforation

15

 fixing nut

16

 side panel

17

 control device

18

 sensor

19

 sensor

20

 Speed sensor

21

 acceleration signal

a

 acceleration

t

 Time

S ₁

 threshold

S ₂

 threshold

S ₃

 threshold

I

 Area

II

 Area

III

 Area

IV

 Area

V

 Area

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 202012001457 U1 [0002]

Claims (10)

Drive device for a sliding carriage, in particular a sliding walker, comprising a wheel hub motor ( 10 ) with a rotor ( 11 ) and a stator ( 12 ), wherein the rotor ( 11 ) with an impeller to be driven ( 4 ), and the stator ( 12 ) on one axis ( 13 ) is arranged, the one or both sides of the wheel hub motor ( 10 ) for connection to a suspension ( 9 ) of the sliding carriage ( 1 protruding, wherein the motor side at least one sensor ( 18 ) for detecting a measure of one on the sliding carriage ( 1 ) applied thrust force representing information on the axle ( 13 ) and the operation of the wheel hub motor ( 10 ) in dependence on the detected information controlling control device ( 17 ) is provided. Drive device according to claim 1, characterized in that the sensor ( 18 ) is designed to measure a bend or a twist of the axle. Drive device according to claim 2, characterized in that the sensor ( 18 ) on the axle ( 13 ) arranged strain gauge is. Drive device according to 1, characterized in that the sensor ( 18 ) is a pressure measuring sensor, which on the axis ( 13 ) is arranged in the region to be arranged in the wheel suspension. Drive device according to claim 4, characterized in that the sensor ( 18 ) is a tension-pressure sensor or a piezoelectric film sensor. Drive device according to one of the preceding claims, characterized in that a sensor ( 19 ) is provided for detecting an acceleration information representing a measure of the acceleration, wherein the control device ( 17 ) for controlling the operation of the wheel hub motor ( 10 ) is formed as a function of the acceleration information. Drive device according to one of the preceding claims, characterized in that a sensor ( 19 ) for detecting a the spatial position of the wheel hub motor ( 10 ) is provided, wherein the control device ( 17 ) for controlling the wheel hub motor ( 10 ) is formed as a function of the position information. Claim 6 or 7, characterized in that the sensor ( 19 ) is a 3-axis sensor. Drive device according to one of the preceding claims, characterized in that a sensor ( 20 ) for detecting the rotational speed of the rotor ( 11 ) is provided, wherein the control device ( 17 ) for controlling the wheel hub motor ( 10 ) is formed as a function of the rotational speed. Drive device according to claim 9, characterized in that the sensor ( 20 ) is a light barrier sensor or a Hall sensor.

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