CN210903712U

CN210903712U - Wheel chair

Info

Publication number: CN210903712U
Application number: CN201920315459.9U
Authority: CN
Inventors: 安德烈亚斯·纳沃尔德
Original assignee: Meila Co ltd
Current assignee: Meila Co ltd
Priority date: 2018-03-13
Filing date: 2019-03-13
Publication date: 2020-07-03
Anticipated expiration: 2029-03-13
Also published as: DE102018129289A1

Abstract

The utility model relates to a manual wheelchair (2), for example the wheelchair that has the hand rim, the wheelchair has frame (4), stopper (10) and electronic friction wheel drive (12), wherein, be equipped with drive wheel (6, 8) that have the tire on the frame, stopper (10) can be placed in the engaged state and can be placed in the disengaged state for the mode of going in order to make wheelchair (2) braking, friction wheel drive (12) then can be placed in the engaged state for the mode of going of electronic, can be placed in the disengaged state for the mode of going in hand. According to the invention, the brake (10) and the friction wheel drive (12) are operatively connected to a common actuating element in order to bring the brake (10) and the friction wheel drive (12) into engagement and into disengagement.

Description

Wheel chair

Technical Field

The utility model relates to a wheelchair, in particular to a wheelchair with hand rims.

Background

Wheelchairs and wheelchairs designed with hand rims are well known. They have a frame on which a drive wheel with a tire is arranged. The known wheelchairs also have a brake which can be put into engagement in order to brake the wheelchair and into disengagement in order to allow it to travel.

Accordingly, wheelchairs enable persons with limited walking ability to independently advance in the wheelchair by means of the muscle force of their arms.

In existing wheelchairs, support of the electric drive is currently desired. For this purpose, it is known, in particular, to equip wheelchairs with an electric friction wheel drive, in which the drive torque of an electric motor is transmitted via friction wheels to the wheels of the wheelchair.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a wheelchair with improved practicability, in particular to a wheelchair with hand rims.

This object is solved by the following solution.

The utility model discloses based on following design: the utility of the wheelchair is improved in that the brake and the friction wheel drive are operated by a common operating element, so that the operation of the wheelchair is simplified. To this end, the invention provides that the brake and the friction wheel drive are operatively connected to a common actuating element in order to bring the brake and the friction wheel drive into the engaged state and into the disengaged state. That is to say, since the brake and the friction wheel drive are actuated by the same actuating element, the operation of the wheelchair equipped with the friction wheel drive is significantly simplified and becomes safer.

According to the utility model discloses a friction wheel drive can install simply and fast and dismantle simultaneously can also install additional to current wheelchair on.

Another advantage of the friction wheel drive according to the present invention is that it does not increase the weight of the wheelchair much while significantly extending the function of the wheelchair.

It is also advantageous that the friction wheel drive, if arranged correspondingly on the wheelchair frame, does not enlarge the width of the wheelchair and does not affect its foldability.

In addition to the mounting points of the friction wheel drive unit, the friction wheel drive according to the invention does not require further modifications on the frame of the wheelchair, in particular no influencing factors in the form of holes or similar structures.

According to an advantageous development of the invention, the common actuating element can have a manually actuatable actuating element.

In order to simplify the actuating design of the brake and the friction wheel drive, according to a further advantageous development of the invention, the manually actuatable actuating element has:

a neutral position in which the brake and the friction wheel drive are both in a disengaged state,

-a braking position in which the brake is engaged and the friction wheel drive is disengaged, and

-a friction wheel drive position in which the brake is in a disengaged state and the friction wheel drive is in an engaged state.

According to an advantageous development of the aforementioned embodiment, the braking position corresponds to a front end position, viewed in the direction of travel of the wheelchair, the neutral position corresponds to a rear end position, viewed in the direction of travel of the wheelchair, and the friction-wheel drive position corresponds to an intermediate position of the actuating element. In this way, the known manner of actuating conventional wheelchair brakes is retained.

According to the invention, the actuating element can be designed in different ways according to the respective requirements and the specific circumstances. In accordance with an advantageous development of the invention, the manually actuable actuating element is therefore designed as an actuating lever.

In the above-described embodiment, it is preferred that the operating lever is mounted so as to be pivotable about a lever axis which is fixed in position with respect to the frame of the wheelchair — as an advantageous development of the invention.

According to the utility model discloses, required effect between control rod and stopper and the friction wheel drive is connected can be according to corresponding requirement and particular case with different mode establishments. In this respect, according to a particularly advantageous development of the invention, the actuating lever is operatively connected to the brake and the friction wheel drive via a lever mechanism, which is designed in the following manner:

in the neutral position, both the brake and the friction wheel drive are put in a disengaged state;

in the braking position, the brake is placed in the engaged state and the friction wheel drive is placed in the disengaged state, and

in the friction wheel drive position, the brake is placed in the disengaged state and the friction wheel drive is placed in the engaged state.

The movement characteristics of the lever actuator may be designed such that the brake and the friction wheel drive may be simultaneously brought into an engaged state or a disengaged state, respectively, when switching between different positions of the operating element.

In principle, the friction wheel drive is fixedly mounted on the wheelchair. However, according to a particularly advantageous development of the invention, the friction wheel drive is designed as a friction wheel drive unit which is designed such that it can be mounted on or removed from the wheelchair without tools. In this way, the friction wheel drive can be installed and used by the wheelchair user when required, for example in order to climb a slope, and removed again after use, without requiring tool operation.

An advantageous development of the aforementioned embodiment provides a locking device for locking the friction wheel drive unit in the mounted position. In this way, the friction wheel drive unit is prevented from being undesirably loosened during use.

According to an advantageous further development of the embodiment with a lever mechanism, the lever mechanism has a first partial transmission assigned to the friction-wheel drive and a second partial transmission assigned to the brake.

According to an advantageous further development of the aforementioned embodiment, the first partial transmission has a two-armed first lever which is mounted so as to be rotatable about a first axis which is fixed in position with respect to the frame of the wheelchair, wherein one end of the two-armed first lever supports a friction wheel of the friction wheel drive in the mounted position of the friction wheel drive and the other end of the two-armed first lever is rotatably connected to one end of a first crank which is rotatably connected to the operating lever eccentrically with respect to the lever axis of the operating lever, and/or the second partial transmission has a one-armed second lever which is rotatably mounted about a second axis which is fixed in position with respect to the frame of the wheelchair, wherein the free end of the second lever supports a braking element of the brake and is rotatably connected to the second lever at a position remote from the end thereof with one end of the second crank The other end of the second crank is rotatably connected to the lever eccentrically with respect to the main shaft of the lever.

In order to design the movement behavior of the lever actuator particularly advantageously in the above-described embodiment, according to an advantageous development of the invention, the stationary spindle, the stationary first shaft and the stationary second shaft are arranged on a straight line.

In order to achieve a certain locking effect of the lever mechanism in the braking position or in the friction wheel drive position, according to an advantageous development of the invention the first partial transmission rod arrangement forms a dead point arrangement which is in the dead point position in the friction wheel drive position and/or the second partial transmission arrangement forms a dead point arrangement which is in the dead point position in the braking position. The respective dead center device prevents the lever mechanism from being moved undesirably from the selected position (braking position or friction-wheel drive) to another position, i.e., without actuating the actuating element.

According to an advantageous development of the invention, in a friction wheel drive unit for a wheelchair alone, which has the independent inventive meaning, the friction wheel drive unit has a measuring roller which, in the installed position of the friction wheel drive unit, is preferably pressed against the tire of the wheelchair in a spring-loaded manner and is in rotary drive connection with a rotary encoder which is in signal-transmitting connection with a control device which is designed and programmed in such a way that the friction wheel drive unit is or can be actuated as a function of the output signal of the rotary encoder.

The measuring roller can be used, for example, and in particular for determining an actual rotational speed of a drive wheel of the wheelchair assigned to the friction wheel drive, which deviates from the rotational speed expected on the basis of the rotational speed of the friction wheel drive, for example due to slipping. In accordance with an advantageous development of the aforementioned embodiment, the control device is therefore designed and programmed such that the actual rotational speed of the drive wheels of the wheelchair driven by the friction wheel drive unit is determined or can be determined from the output signal of the rotary encoder.

According to a further advantageous development, the embodiment with a measuring roller allocates one friction wheel drive unit to each of the two drive wheels of the wheelchair and the rotary encoder of the measuring roller of the friction wheel drive unit is in signal-transmitting connection with a control device, which is designed and programmed such that the two friction wheel drive units are or can be actuated depending on the output signal of the rotary encoder. In this way, for example, the rotational speeds of the friction wheel drive units assigned to the two drive wheels can be controlled or regulated independently of one another, so that a straight-line travel of the wheelchair can be ensured even if a slip occurs between the friction wheel drive unit and the drive wheels if the wheelchair user has actuated the operating unit of the friction wheel drive for straight-line travel.

According to an advantageous development of the above-described embodiment, the rotational speeds of the friction wheel drive units can be controlled or regulated independently of one another as a function of the output signals of the measuring rollers.

According to a further advantageous development of the invention, the brake has a support element connected to the wheelchair frame, on which support element a brake element is provided, which brake element can be moved between an engaged position and a disengaged position, wherein in the engaged position the brake is in the engaged state; in the disengaged position, the brake is in the disengaged state, in which a receptacle for mounting the friction wheel drive unit is formed on the support element. In this embodiment, the support element of the brake forms both the receptacle and the mounting point for the friction wheel drive unit.

The or each friction wheel (friction roller) of the friction wheel drive can be made of any suitable material according to the respective requirements. For example and in particular, the friction wheel can consist of steel, for example stainless high-grade steel, and have a knurling on its outer periphery. In this way, the friction wheel is not susceptible to environmental influences and mechanical wear does not occur easily.

According to a further advantageous development, the actuating element is in operative connection with the friction wheel drive, so that the actuating element energizes the friction wheel drive. In this embodiment, the friction wheel drive is energized or de-energized when the actuating element is placed in the respective position. In this way, a separate switch for electrically switching the friction wheel drive is produced.

For example, and in particular, at least one control lever can be provided for controlling the friction wheel drive, which control lever can be provided, for example, and in particular, on the housing of the friction wheel unit. More than one control rod may be provided according to the respective requirements, for example a separate control rod for each friction wheel drive unit in the case of two friction wheel drive units on the housing. For example, it is also possible to arrange the control lever on the push handle of the wheelchair so that the friction wheel drive is operated by the accompanying person.

The control of the friction wheel drive can also be effected, for example, by a smartphone, which is carried along by the wheelchair user or by an accompanying person. The control can also be carried out by a separate manual transmitter according to the respective requirements. In the case of a corresponding wireless operating unit, the control connection to the friction wheel drive is preferably established by radio communication.

The friction wheel drive unit, in particular the electromechanical components of the original electric drive, the associated electronic control unit and the battery or accumulator, can be accommodated in or arranged on the housing of the friction wheel drive unit according to the respective requirements.

In order to avoid a malfunction of the friction wheel drive, it is advantageous if the tires of the wheelchair are equipped with a tire pressure control system. By maintaining a predetermined or predetermined tire pressure, it is ensured that the friction wheels of the friction wheel drive are always positioned in a predetermined contact manner on the respective tires of the wheelchair.

For mounting the friction wheel drive unit on the wheelchair frame, for example and in particular an adapter connected to the frame by a clamping connection can be used. In this way, existing wheelchairs can be equipped or retrofitted with a friction wheel drive according to the invention in a simple and uncomplicated manner.

If both wheels of the wheelchair are to be driven, a separate friction wheel drive unit is assigned to each wheel. However, it is also possible according to the invention to use a friction wheel drive unit on only one wheel, whereby the respective wheel is driven electrically and the wheelchair user drives the other wheel by hand. The corresponding embodiment is of great significance in particular for persons with a limited body half.

Drawings

The invention is explained in more detail below with reference to the appended, partially simplified drawings according to embodiments. All features described in the description, shown in the drawings and claimed in the claims constitute the subject matter of the invention both individually and in any suitable combination with one another, independently of their generalization in the claims and their references and independently of their description or their illustration in the drawings.

In the figure:

figure 1 shows in perspective one embodiment of a wheelchair according to the invention,

figure 2 shows in perspective and partly in perspective view a friction wheel drive unit in combination with a wheelchair,

figure 3 shows in side view the friction wheel drive unit in combination with a wheelchair according to figure 2,

figure 4 shows the friction wheel drive unit according to figure 2 in another perspective view,

fig. 5 shows the friction wheel drive unit according to fig. 4 in the same view as fig. 4, wherein the housing of the friction wheel drive unit has been omitted for reasons of illustration,

figure 6 shows in a perspective exploded view the components of the friction wheel drive unit in the area of the friction wheel,

figure 7A shows the joystick in a side view in a neutral position,

figure 7B shows the joystick in the friction wheel drive position from the same view as figure 7A,

figure 7C shows the lever in the detent position from the same view as figure 7A,

figure 8 shows in a side view the steering unit of the wheelchair according to figure 1,

figure 9 shows the steering unit of figure 8 in a perspective view,

figure 10 shows the steering unit of figure 8 in another side view,

figure 11 shows the steering unit of figure 8 in another perspective view,

figure 12 shows the locking device for locking the friction wheel drive unit in a first position,

figure 13 shows the locking device of figure 12 in a second position,

figure 14 shows the components of the locking device in a perspective view,

fig. 15 shows the components of the locking device according to fig. 14 in a perspective exploded view and

figure 16 shows the components of the locking device of figure 14 in another exploded perspective view.

Detailed Description

An embodiment of a wheelchair according to the invention is described in detail below with reference to figures 1 to 16.

In fig. 1 is shown in perspective an embodiment of a hand-propelled wheelchair 2 according to the invention, designed as a wheelchair with a hand rim. The wheelchair 2 has a frame 4 on which drive

wheels

6, 8 with tires are provided. The wheelchair 2 has a brake 10 which can be put into an engaged state for braking the wheelchair 2 and into a disengaged state for the travel mode.

The wheelchair 2 also has a friction wheel drive 12 which can be brought into engagement for the electric drive mode and into disengagement for the manual drive mode.

According to the invention, the brake 10 and the friction wheel drive 12 are operatively connected to a common actuating element in order to bring the brake 10 and the friction wheel drive 12 into and out of engagement.

In the exemplary embodiment shown, the common actuating element is a manually actuatable actuating element in the form of an actuating lever 14 (see fig. 1).

For the common actuation of the brake 10 and the friction wheel drive 12, the operating lever 14 has a neutral position, a braking position and a friction wheel drive position, wherein in the neutral position both the brake and the friction wheel drive are in a disengaged state; in the braking position, the brake is in an engaged state and the friction wheel driving device is in a disengaged state; and in the friction wheel drive position, the brake is disengaged and the friction wheel drive is engaged. As will be explained in more detail later on with reference to fig. 7A to 7C, in the embodiment shown the braking position corresponds to a front end position as seen in the direction of travel of the wheelchair 2, the neutral position corresponds to a rear end position as seen in the direction of travel of the wheelchair and the friction wheel drive position corresponds to a position between the two of the operating levers 14.

In the embodiment shown, the friction wheel drive 12 has friction wheel drive units which are designed such that they can be mounted on the wheelchair 2 or dismounted from the wheelchair 2 without tools. Only the friction wheel drive unit 16 associated with the wheel 8 will be described in detail below. The respective friction wheel drive unit of the distribution wheel 6 has a corresponding configuration. Therefore, it is not explained in detail here and the drive unit is omitted from the figures for the sake of clarity.

The friction wheel drive unit 16 is shown in fig. 2 and 3 together with the wheelchair 2 and in fig. 4 and 5 separately without the wheelchair 2.

The friction wheel drive unit 16 has a friction wheel 18 which is in rotary driving connection with an electric motor 20 (see fig. 2 and 3). In the installed position of the friction wheel drive unit 16, the friction wheel 18 rests against the radially outer surface of the drive wheel 8, so that the drive wheel 8 is driven in rotation when the friction wheel 18 is rotated. The friction wheel drive unit 16 and the further friction wheel drive unit associated with the drive wheels 6 are in control connection with a common control device, so that the two friction wheel drive units drive the

drive wheels

6, 8 of the wheelchair 2 according to the direction of travel and the speed of travel desired by the user of the wheelchair 2.

In this way, the user of the wheelchair 2 is supported in the electric drive mode when required. For this purpose, the user of the wheelchair 2 can install the friction wheel drive 12 in the form of the friction wheel drive unit 16 and the further friction wheel drive unit without tools if necessary and can detach them in a corresponding manner without tools when he wishes to return to the manual driving mode.

Fig. 2 and 3 show the friction wheel drive unit 14 in a state of being detached from the wheelchair 2. In order to lock the friction wheel drive unit 16 in the mounted position, locking devices 22 are provided, which will be explained in more detail below with reference to fig. 12 to 16.

In fig. 2, the support element 24 of the brake 10 can be seen, which is connected to the frame 4 of the wheelchair 2 by means of a clamping block 26. On the support element 24 there is a braking element 28, which is movable between an engagement position, in which the braking element 28 is in an engaged condition, and a disengagement position; in the disengaged position, the braking element 28 is in a disengaged state. A receptacle 30 is formed on the support element 24, into which the friction wheel drive unit 16 can be inserted for mounting on the wheelchair 2 via a floating shaft 32. The support element 24 of the brake 10 thus forms a receptacle and a mounting point for the friction wheel drive unit 16. The mounting of the friction wheel drive unit 16 on the receptacle 30 will be explained in detail below with reference to fig. 12 to 16.

Fig. 4 shows the friction wheel drive unit 16 in a mounted position on the support element 24. For the sake of clarity, the friction wheel drive unit 16 is shown only with the support element 24 in fig. 4, while the other components of the wheelchair 2 are omitted.

In fig. 4, a braking element 28 can be seen, which is brought into engagement with the radially outer surface of the tire of the drive wheel 8 by means of the actuating lever 14 in the braking position of the actuating lever for braking the wheelchair 2. In addition, in fig. 4, a friction wheel 18 can also be seen, which in a friction wheel drive position is in engagement with the radially outer surface of the tyre of the drive wheel 8. The radially outer surfaces of both the friction wheel 18 and the braking element 28 may preferably be constructed of an elastomeric material. The components of the friction wheel drive unit 16 are housed in a housing 34. In fig. 4, the locking lever 35 of the locking device 22 can also be seen, the function of which will be explained in more detail later on.

Fig. 5 shows the friction wheel drive unit 16 without the housing 34, wherein battery cells 36 are visible, which are used to supply the electric motor 20 of the friction wheel drive unit 16. The battery cell 36 may be a rechargeable battery cell.

Fig. 6 shows a detail of the friction wheel drive unit 16 in the region of the friction wheel 18 in a perspective view. The friction wheel 18 is in rotary driving connection with the electric motor 20, so that the friction wheel 18 rotates when the output shaft of the electric motor 20 rotates and drives the drive wheel 8 of the wheelchair 2 in rotation in the installed position of the friction wheel drive unit 16.

As will be explained in more detail below with reference to fig. 7A to 11, the operating lever 14 is operatively connected to the brake 10 and the friction wheel drive unit 16 such that in the neutral position, both the brake 10 and the friction wheel drive 12 are disengaged; in the braking position, the brake 10 is engaged and the friction wheel drive 12 is disengaged; and in the friction wheel drive position, the brake 10 is disengaged and the friction wheel drive 12 is engaged.

Fig. 7A shows the operating lever 14 in a neutral position in which both the friction wheel 18 and the braking element 28 are in a disengaged condition from the radially outer surface of the driving wheel 8. In this neutral position, the wheelchair 2 can be manually driven by the user.

Fig. 7B shows the lever 14 in a friction wheel drive position in which the friction wheel 18 is in engagement with the radially outer surface 38 of the drive wheel 8, so that the drive wheel 8 is rotationally driven by the friction wheel drive unit 16. At the same time, in the friction wheel drive position, the brake element 28 is in a disengaged state.

Figure 7C shows the operating lever 14 in a braking position in which the braking element 28 is in engagement with the radially outer surface of the drive wheel 8, so that the wheelchair 2 is braked. At the same time, in the braking position, the friction wheel 18 is in a disengaged condition with the radially outer surface 38 of the driving wheel 8.

The functional connection between the operating lever 14 and the brake 10 and the friction wheel drive unit 16 according to the invention is explained in detail below with reference to fig. 8 to 11.

The operating lever 14 is mounted so as to be able to rotate about a lever axis 40 fixed in position with respect to the frame 4 of the wheelchair 2 and is in operative connection with the brake 10 (brake element 28) and the friction wheel drive 12 (friction wheel 18 of the friction wheel drive unit 16) via a lever transmission 42, in such a way that: in the neutral position (fig. 7A), both the brake 10 and the friction wheel drive 12 are disengaged; in the friction wheel drive position (see fig. 7B), the brake 10 is in the disengaged state and the friction wheel drive 10 is in the engaged state and in the braking position, the brake 10 is in the engaged state and the friction wheel drive 12 is in the disengaged state (see fig. 7C).

The lever gear 42 has a first partial gear 44 assigned to the friction-wheel drive 12 and a second partial gear 46 assigned to the brake 10.

The first partial transmission 44 has a two-armed first lever 48 which is mounted on the support element 24 and thus on the frame 4 of the wheelchair 2 so as to be rotatable about a first axis 50 which is fixed in position with respect to the frame 4 of the wheelchair 2. One end of the two-armed first lever 48 has a receptacle 30 and supports the friction wheel 18 in the installed position of the friction wheel drive unit 16. The other end of the first lever 48 is rotatably connected (pivot point 51) to one end of a first crank 52, and the other end of the first crank is eccentrically and rotatably connected (pivot point 49) to the lever shaft 40 of the lever 14 to the lever 14.

The second sub-transmission 46 has a single-arm second lever 54 which is supported so as to be able to rotate about a second axis 56 which is fixed in position with respect to the frame 4 of the wheelchair 2. The free end of the second lever 54 supports the braking element 28. One end of a second crank 58 is rotatably connected (pivot 57) to the second lever 54 at a position remote from the end thereof, and a second end of the second crank is rotatably connected (pivot 55) to the operating lever 14 eccentrically with respect to the lever shaft 40 of the operating lever.

The fixed axle 40, the fixed first axle 50 and the fixed second axle 56 are arranged in a straight line.

The first sub-transmission 44 forms a dead-center device which is located at a dead-center position in the friction wheel drive position (see fig. 7B). In a corresponding manner, the second partial transmission 46 also forms a dead-center device, which is located in a dead-center position in the braking position (see fig. 7C).

As can be seen from the figures and in particular from a comparison of fig. 7A to 7C, the resulting movement characteristic is such that, in the movement of the operating lever 14 from the neutral position shown in fig. 7A in the direction of the friction wheel drive position shown in fig. 7B, the friction wheel 18, i.e. the brake element 28, is moved in the radial direction in the tire direction of the drive wheel 8. The length ratio of the lever gear 42 is selected here such that in the friction wheel drive position (see fig. 7B), in which the friction wheel 18 rests radially against the tire of the drive wheel 8, the braking element 28 is also spaced radially from the tire of the drive wheel 8.

In a further movement of the actuating lever 14 from the friction wheel drive position according to fig. 7B into the braking position according to fig. 7C, the braking element 28 continues to move in the radial direction in the direction of the tire of the drive wheel 8 until it comes into contact with the tire of this drive wheel in the braking position and the brake 10 is therefore engaged. At the same time, in the movement of the lever 14 from the friction wheel drive position into the braking position, the friction wheel 18 moves again away from the tire of the friction wheel 8, so that the friction wheel 18 disengages from the tire.

That is, in the movement of the lever from the neutral position shown in fig. 7A into the braking position shown in fig. 7C, the braking element 18 performs a continuous movement in the tire direction, while the friction wheel 18 first performs a movement in the tire direction and contacts the tire in the friction wheel drive position (see fig. 7B), and then moves away from the tire again in the manipulation of the lever from the friction wheel drive position into the braking position.

The actuation of the brake 10 and the friction wheel drive 12 by means of a common operating lever 14 makes a particularly simple and direct operation of the wheelchair 2 possible. Here, in the selected movement characteristic, the braking position corresponds to the front end position as seen in the direction of travel, as is well known from manual wheelchairs which do not have a friction wheel drive. Therefore, a re-study or re-learning is not necessary for the user of a conventional wheelchair.

In fig. 9 to 11, various views of the support element 24 are shown in addition to the actuating lever 14 and the lever actuator 42, the lever of the lever actuator 42 and the arrangement of the respective pivot point being further explained.

The function of the locking device 22 is explained in detail below with reference to fig. 12 to 16.

As shown in fig. 2 and 3, the locking device 22 has a float shaft 32 which is rotatably arranged on a housing 34 of the friction wheel drive unit 16 and is connected to the locking lever 32 in a rotationally fixed manner. The floating shaft 32 has a transverse pin 60 in the region of its free end. The receptacle 30 is formed in an outer part 62 (see in particular fig. 15) which is rotatably arranged on an inner part 64 which is connected to the support element 24 in a rotationally fixed manner. A spring 66 acts between the outer member 62 and the inner member 64.

Fig. 14 shows the outer member 62 in a state of being mounted on the inner member 64.

Figure 15 shows outer member 62 in a state of having been removed from inner member 64,

fig. 16 shows respective parts forming the accommodating portion 30 in an exploded view.

To install the friction wheel drive unit 16, the floating shaft 32 is inserted into the receptacle 30 until it stops. The rotational position of the float shaft 32 is determined here by the transverse pin 60 which engages in the

recesses

68, 70 of the receptacle 30. The float shaft 32 is then rotated counterclockwise by the locking lever 35 in fig. 2 until the projection 72 of the locking lever 35 snaps into a complementary shaped recess 74 on the sleeve 76 to the projection 72 (see fig. 12 and 13). For this purpose, the portion of the locking lever 35 having the projection 72 is spring-loaded leftward in fig. 12 in the axial direction of the float shaft 32 with respect to the sleeve 76.

In the latched position of the locking lever 35, the transverse pin 60 is pivoted relative to the

recesses

68, 70 and is therefore prevented from axial movement, so that in this way the friction wheel drive unit 16 is locked to the support element 24 and therefore to the frame 4 of the wheelchair 2.

By the projection 72 engaging in a form-fitting manner in the recess 74 on the sleeve 76, in combination with the axial spring loading, unintentional release of the friction wheel drive unit 16 is prevented. For releasing, the locking lever 35 needs to be pulled to the right in fig. 13 against the axial spring loading force and then rotated clockwise in fig. 2, so that the projection leaves the recess 74 and moves the locking lever 35 back again into the position shown in fig. 12, in which the friction wheel drive unit 16 can be pulled out of the receptacle 30 and removed.

When the floating shaft 32 is rotated while the friction wheel drive unit 16 is locked, at the same time, the spring 66 is tensioned, so that the friction wheel drive unit 16 is spring-loaded into engagement with the radially outer surface of the tire of the drive wheel 8 via a measuring roller 78 rotatably supported on the housing 34 of the friction wheel drive unit 16. In the friction wheel drive position of the actuating lever 14, the friction wheel drive unit 16 is therefore pressed against the radially outer surface of the tire, on the one hand, by the friction wheel 18 and, on the other hand, by the measuring roller 78. Thus, the friction wheel drive unit 16 is ensured to be in contact with the tire as specified.

The measuring roller 78 is in rotary drive connection with a rotary encoder, which is itself in signal-transmitting connection with a control device for actuating the friction-wheel drive unit 16.

Due to the slip between the friction wheel 18 and the tires of the drive wheel 8, the rotational speed of the drive wheel 8 may deviate from the rotational speed specified by the friction wheel drive unit 16. If different slip conditions occur on the two

drive wheels

6, 8, the rotational speeds of the

drive wheels

6, 8 will differ, so that the wheelchair 2 will not travel in a straight line, but in a curved line, despite the same rotational speed of the friction wheel drive unit assigned to the

drive wheels

6, 8.

By determining the actual rotational speed of the

drive wheels

6, 8 by means of the measuring rollers 78 of the friction wheel drive unit 16, the rotational speed of the friction wheel drive unit can be controlled or regulated independently of one another, so that the wheelchair 2 travels in a straight line if the user of the wheelchair 2 plans such a route by means of the operating unit of the friction wheel drive 12.

In this way, the driving comfort and driving safety of the wheelchair 2 are improved.

Of course, by correspondingly different control or regulation of the rotational speed of the friction wheel drive unit 16 assigned to the

drive wheels

6, 8, an arbitrary curve drive is possible.

In addition, the measuring roller 78 also makes possible further travel functions. Since the measuring rollers 78 are always in engagement with the

drive wheels

6, 8 of the wheelchair 2, the actual rotational speed of the

drive wheels

6, 8 is measured in the neutral position of the operating lever 14, i.e. in the manual mode of the wheelchair 2. It is then possible, for example, for the user to manually accelerate the wheelchair 2 to the desired speed and the speed that has been reached before to be stored by the control device. Then, when the user of the wheelchair energizes the friction wheel drive means by placing the joystick 14 in the friction wheel drive position, the stored desired speed can be set and kept constant by a corresponding control or adjustment of the rotational speed of the friction wheel drive unit.

The arrangement of the measuring roller in rotary drive connection with the rotary encoder, alone and independently of the design of the joint actuation of the brake and the friction wheel drive according to the invention, enjoys the independent inventive significance in the friction wheel drive of a wheelchair.

Claims

1. Manual wheelchair (2) comprising a hand rim, characterized in that it comprises:

a frame (4) on which a drive wheel with a tyre is provided;

a brake (10) which is placed in an engaged state for braking the wheelchair (2) and in a disengaged state for a travel mode; and

an electric friction wheel drive (12) which is brought into engagement for the electric drive mode and into disengagement for the manual drive mode,

characterized in that the brake (10) and the friction wheel drive (12) are operatively connected to a common actuating element in order to bring the brake (10) and the friction wheel drive (12) into engagement and into disengagement.

2. The wheelchair of claim 1 wherein the common operating element is or has a manually operable operating element.

3. The wheelchair of claim 2 wherein the manually manipulable member has:

-a neutral position in which both the brake (10) and the friction wheel drive (12) are in a disengaged condition;

-a braking position in which the brake (10) is engaged and the friction wheel drive (12) is disengaged; and

-a friction wheel drive position in which the brake (10) is in a disengaged state and the friction wheel drive (12) is in an engaged state.

4. A wheelchair according to claim 3, characterised in that the braking position is a front end position, seen in the direction of travel of the wheelchair (2), the neutral position is a rear end position, seen in the direction of travel of the wheelchair (2), and the friction wheel position is an intermediate position of the operating element.

5. The wheelchair as claimed in claim 3, characterized in that the manually actuatable operating element is designed as an operating lever (14).

6. The wheelchair according to claim 5, characterised in that the operating lever (14) is supported in an oscillating manner about a lever shaft (40) which is fixed in position with respect to the frame of the wheelchair (2).

7. The wheelchair as claimed in claim 5, characterized in that the operating lever (14) is in operative connection with the brake (10) and the friction wheel drive (12) via a lever transmission (42) which is designed to:

-in the neutral position, the brake (10) and the friction wheel drive (12) are both in a disengaged state,

-in the braking position, the brake (10) is engaged and the friction wheel drive (12) is disengaged, and

-in the friction wheel drive position, the brake (10) is in a disengaged state and the friction wheel drive (12) is in an engaged state.

8. Wheelchair according to claim 1, characterized in that the friction wheel drive (12) has at least one friction wheel drive unit (16) which is designed to be mounted on the wheelchair (2) or dismounted from the wheelchair (2) without tools.

9. The wheelchair as claimed in claim 8, characterized in that locking means (22) are provided for locking the friction wheel drive unit (16) in the mounted position.

10. The wheelchair as claimed in claim 7, characterized in that the lever gear (42) has a first sub-gear (44) assigned to the friction-wheel drive (12) and a second sub-gear (46) assigned to the brake (10).

11. The wheelchair as claimed in claim 10, characterized in that the first partial transmission (44) has a two-armed first lever (48) which is mounted so as to rotate about a first axis (50) which is fixed in position with respect to the frame (4) of the wheelchair (2), wherein one end of the two-armed first lever (48) supports the friction wheel (18) of the friction wheel drive (12) in the installed position of the friction wheel drive (12), and wherein the other end of the two-armed first lever is connected so as to rotate eccentrically with respect to the lever axis (40) of the lever (14) to one end of a first crank (52).

12. The wheelchair as claimed in claim 10, characterized in that the second sub-transmission (46) has a single-armed second lever (54) which is mounted so as to rotate about a second axis (56) which is fixed in position with respect to the frame (4) of the wheelchair (2), wherein the free end of the second lever (54) supports a brake element (28) of the brake (10) and is connected rotatably at its end remote from one end to one end of a second crank (58) whose other end is connected rotatably to the operating lever (14) eccentrically with respect to its lever axis (40).

13. The wheelchair according to claim 12, characterized in that the stationary axle (40), the stationary first axle (50) and the stationary second axle (56) are arranged in a straight line.

14. The wheelchair as claimed in claim 10, characterized in that the first sub-transmission (44) forms a dead-center device which is located in the dead-center position in the friction-wheel drive position.

15. The wheelchair as claimed in claim 10, characterized in that the second sub-transmission (46) forms a dead-center device which, in the braking position, is located in the dead-center position.

16. Wheelchair according to claim 8, characterized in that the friction wheel drive unit (16) has a measuring roller (78) which, in the mounted position of the friction wheel drive unit, bears in a spring-loaded manner against the tires of the wheelchair (2) and is in rotary drive connection with a rotary encoder which is in signal-transmitting connection with a control device which is designed and programmed to operate the friction wheel drive unit (16) as a function of the output signal of the rotary encoder.

17. The wheelchair as claimed in claim 16, characterized in that the control device is designed and programmed to determine from the output signal of the rotary encoder the actual rotational speed and the peripheral speed of the drive wheels of the wheelchair (2) driven by the friction wheel drive unit (16).

18. Wheelchair according to claim 16, characterized in that one friction wheel drive unit (16) is associated with each of the two drive wheels of the wheelchair (2) and in that the rotary encoder of the measuring roller of the friction wheel drive unit (16) is in signal-transmitting connection with the control device, which is designed and programmed to operate both friction wheel drive units (16) in dependence on the output signal of the rotary encoder.

19. The wheelchair as claimed in claim 18, characterized in that the rotational speed of the friction wheel drive unit (16) is controlled or regulated independently of one another on the basis of the output signal of the measuring roller.

20. Wheelchair according to any of the preceding claims 8-9, 16-19, characterised in that the brake (10) has a support element (24) which is connected to the frame (4) of the wheelchair (2), on which support element a brake element (28) is provided which can be moved between an engaged position, in which the brake element (28) is in an engaged state, and a disengaged position, in which the brake element (28) is in a disengaged state, wherein a receptacle for mounting the friction wheel drive unit (16) is formed on the support element (24).