EP2334275A1

EP2334275A1 - Method and device for propelling a wheelchair

Info

Publication number: EP2334275A1
Application number: EP09814137A
Authority: EP
Inventors: Jarmo MÄNTSÄLA
Original assignee: Mideco-Fin Oy
Current assignee: Mideco-Fin Oy
Priority date: 2008-09-17
Filing date: 2009-09-17
Publication date: 2011-06-22
Also published as: FI20090340A0; FI20090340A; FI121913B; FI20080525A0; WO2010031895A1; FI20080525A

Abstract

A method and apparatus for propelling a wheelchair (10), wherein the wheelchair is coupled to a cart (20) which is propelled along a closed circuit track (30) so that the wheelchair moves along a base (31 ), pulled by the cart. The small front wheels (11 ) of the wheelchair are placed on top of the cart, whereby the cart pulls the wheelchair, either continuously or stopping once in a while, so that the large wheels (12) of the wheelchair rotate freely. The cart most preferably has four pivotable wheels (22). The track comprises a circuit-shaped, endless chain loop (33) located in a groove (32) in the base (31), the cart being coupled to the chain. There is at least one gear (36), rotatable by a motor, in connection with the groove for the purpose of propelling the chain.

Description

METHOD AND DEVICE FOR PROPELLING A WHEELCHAIR

OBJECT OF THE INVENTION

The object of the invention is a method for propelling a wheelchair.

PRIOR ART

A person sitting in a wheelchair can move about by rotating the wheels of the wheelchair by hand. Another known method is to equip the wheelchair with an electric motor, in which case the user only has to steer the chair and use the motor controls. Various solutions, such as elevators etc., have been developed for difficult locations like staircases.

However, if the person in a wheelchair is elderly or a patient suffering from an illness and is not fit enough or capable of independent movement, another person must push the wheelchair. In institutions caring for the elderly, for example, this requires a lot of personnel tasked to take residents out by pushing them around the yard in a wheelchair. The number of required personnel is of course less if the residents are simply taken out in their wheelchairs and left to sit outside. However, it has been observed that moving around outdoors, even if sitting in a wheelchair, is much more invigorating than simply staying put.

The publication US-6,364,594 presents a system in which a lifting device is used to lift a wheelchair and the person sitting in it into a specially constructed cart, which can be propelled on tracks. The system is similar to a train, highly complex, and requires a lot of space. Providing a suitable location for the required tracks is also difficult, and the tracks disturb other traffic.

PURPOSE OF THE INVENTION

The purpose of the present invention is to create a method for propelling a wheelchair in the required manner even in connection with a normal road surface. Thus it is not necessary for the person sitting in the wheelchair to stay put even in case there is no one available to push the wheelchair.

METHOD ACCORDING TO THE INVENTION The method according to the invention is characterised in that a wheelchair is propelled along an even base, such as a road surface, so that the wheelchair is coupled to a cart moving on the said base on wheels, and the cart is propelled by means of a pulling member, such as a chain, located in a groove inlaid in the base so that the wheelchair moves along with the pulling member, pulled by the cart.

Using the method according to the invention, it is possible to take elderly or disabled people sitting in a wheelchair out for fresh air without the personnel needing to push each of the chairs separately. This makes the operation significantly more efficient, as only one person may be required to supervise several persons going out at the same time. The nurse can stay in the supervision area, in a roofed control stand for example, where he/she has a good view over the entire track, or he/she may also walk beside one of the wheelchairs and talk with the person sitting in it. It is also preferable here that the nurse has eye contact with the person sitting in the wheelchair, which is not the case when a wheelchair is pushed in the regular manner from behind. _o

EMBODIMENTS OF THE METHOD

A preferred embodiment of the method according to the invention is characterised in that - the small front wheels of the wheelchair are placed on top of a cart positioned on a base, and as the cart moves along the base, it pulls the wheelchair so that the large wheels of the wheelchair rotate freely.

Another preferred embodiment of the method according to the invention is characterised in that the wheelchair is pulled by means of a cart, using an endless chain located in a groove inlaid in the base, so that the wheelchair moves along with the chain along a closed circuit track.

A third preferred embodiment of the method according to the invention is characterised in that two or more wheelchairs are pulled along the track at a substantially even speed, and all the wheelchairs engaged to the endless chain are stopped once in a while for a desired period of time at an object in connection with the closed circuit track.

DEVICE ACCORDING TO THE INVENTION The object of the invention also includes a device for propelling a wheelchair. The device according to the invention is characterised in that the device is comprised of

a cart, to which the wheelchair can be coupled, the cart comprising pivotable wheels so that it can be moved along an even base, such as a road surface, and a track formed by the even base, such as a road surface, into the surface of which base a groove has been inlaid for a pulling member, a pulling member, which is a moving chain located in the groove inlaid in the base, to which chain the cart is coupled.

EMBODIMENTS OF THE DEVICE

A preferred embodiment of the device according to the invention is characterised in that a cart to be moved along a base has a coupling portion, on top of which the small front wheels of a wheelchair can be placed, the coupling portion consists of two parts and can be laterally adjusted according to the distance between the front wheels of the wheelchair, and the cart has a coupling device to secure the wheelchair to the cart, and the large back wheels of the wheelchair remain on the base, outside the cart.

Another preferred embodiment of the device according to the invention is characterised in that the cart has most preferably four pivotable wheels, and supported by the wheels the cart can be moved along the base in the direction of the track, - the track comprises a circuit-shaped, endless chain loop located in a groove in the base, to which link the cart is coupled, and there is at least one gear, rotatable by a motor, in connection with the groove in the track to propel the circuit chain and the cart coupled to the chain on the base.

EXAMPLES OF EMBODIMENTS

In the following, the invention is described using examples with reference to the appended drawings, in which

> LIST OF FIGURES

Figure 1 shows an axonometric view of a wheelchair coupled to a cart. Figure 2 shows a side view of the wheelchair and the cart in Fig. 1.

Figure 3 shows a schematic top view and a partly sectional view of the cart.

Figure 4 shows a sectional view of Fig. 3 along line IV-IV.

Figure 5 shows a magnified partial view of Fig. 4 at the track. Figure 6 shows a schematic top view of a base and a track in connection with the base.

Figure 7 shows a front view of the cart.

Figure 8 shows a side view of the cart.

Figure 9 shows a top view of a detail of the base and the track.

Figure 10 corresponds to Fig. 5 and shows another embodiment of the track.

DESCRIPTION OF THE FIGURES

Fig. 1 shows a wheelchair 10 and a cart 20, which are coupled to each other. The coupling is executed in the following manner: the wheelchair 10 is pushed partly on top of the cart 20 so that the front wheels 11 of the wheelchair 10 come on top of the cart 20 and go into recesses in the coupling portions 21 of the cart 20. The coupling portions 21 are laterally movable so that their distance to each other can be changed. Thus the coupling portions 21 can be adjusted to such a position that the front wheels 11 of various wheelchairs 10, possibly at different widths, fit into them.

In the embodiment shown in Fig. 1, the wheelchair 10 is secured onto the cart 20 by securing the front wheels 11 of the wheelchair 10 into the recesses of the coupling portions 21. The securing of the wheels can also be executed in another way. Coupling members used for securing the wheels are described in more detail in the following figures. The wheels of the cart 20 and the back wheels 12 of the wheelchair 10 rest on the base 31.

The base 31 in the example of Fig. 1 is provided by an asphalt surface, which can even be a normal road, but it may also be any other relatively even surface, such as slab paving. The road forming the base 31 does not need to be straight or horizontally even. All kinds of bends and turns are possible, and it can also comprise ascending and descending gradients. A track 30 is provided in connection with the base 31 , by means of which the cart 20 and the wheelchair 10 coupled to it are propelled. The track in this connection does not refer to rails, instead in the embodiment presented here, the track 30 is comprised of an even asphalt surface, such as a normal road, into which a guide groove 32 has been formed, by milling for example, for a motive member, i.e. an endless chain, to be placed therein. The chain is shown in more detail in the following figures. When the chain located in the groove is moved, all the carts secured to the chain simultaneously move along with the chain. Thus also all the wheelchairs 10 coupled to the carts 20 move simultaneously.

The cart 20 shown in the example of Fig. 1 also comprises a vertical support 28, a desk 29, and a handle 27 engaged to the vertical support 28. By means of the handle 27 one can secure in place the front wheels 11 of the wheelchair 10 in the recesses of the coupling portions 21 of the cart 20. The handle 27 is intentionally placed in such a location that only a person attending to the person sitting in the wheelchair 10 can reach and grab it. When the wheelchair 10 is coupled to the cart 20 and the cart has started to move, there is thus no risk of the person sitting in the wheelchair 10 accidentally decoupling the wheelchair 10 from the cart 20. The securing mechanism and its alternatives are described in more detail in the following figures.

Fig. 2 shows a side view of the wheelchair 10 and cart 20 coupled to each other on the base 31. The cart 20 stands on the base 31 supported by its wheels 22. The front wheels of the wheelchair 10 are on top of the cart 20, secured to it, and the back wheels 12 of the wheelchair 10 rest on the base 31. The cart 20 is coupled to a movable chain 33 in the track 30 by means of an anchoring member 23, whereby the cart 20 and the wheelchair 10 move along with it, pulled by the track 30.

Fig. 3 shows a schematic top view of the cart 20. The cart 20 comprises four wheels 22, supported by which it moves along the base. The cart 20 is coupled to the movable chain located in the groove 32 of the track 30 by means of an anchoring member 23 so that the cart 20 follows the track 30. In the example of Fig. 3, the track 30 is shown as straight, but the track 30 must also, at least in some sections, be curved because in the presented example, the chain in the groove 32 of the track 30 forms a circuit-shaped, endless loop. Because of this, the wheels 22 of the cart 20 shown in this example are pivotable, and the cart 20 thus adeptly follows the direction of the track 30 and also its curves. The wheels 22 most preferably have limiters which limit the turning angle of the wheels to a value that allows the cart 20 to follow the track.

The wheelchair coupled to the cart 20 is shown only schematically in Fig. 3, with only the front wheels 11 and back wheels 12 drawn. Fig. 3 shows that the front wheels 11 of the wheelchair are pushed on top of the coupling portions 21 of the cart 20, into the recesses therein. To make it easy to push the front wheels 11 of the wheelchair on top of the coupling portions 21, the coupling portions 21 are open on one side. The thus-formed mouth aperture also tapers in a wedge-like fashion. Furthermore, the coupling portions 21 are positioned in a crosswise recess 24 on top of the cart 20 so that the coupling portions are able to move laterally. The lateral motion of the coupling portions 21 makes it possible to adjust them to a suitable distance from each other before the wheelchair is pushed on top of them. The wedge-like tapering mouth apertures of the coupling portions 21 also make it possible to adjust the coupling portions 21 automatically to the correct position in the recess 24 when the front wheels 11 of the wheelchair are pushed to make contact with the coupling portions 21. Due to the adjustment motion of the coupling portions 21, wheelchairs of various wheel-to-wheel widths may be coupled to the cart 20.

Fig. 3 also shows a schematic view of the securing of the front wheels 11 of the wheelchair to the coupling portions 21 of the cart 20. In this example, the securing of the wheels is arranged so that when the front wheels 11 of the wheelchair are in place in the recesses 25 of the coupling portions 21 , securing pins 26 are pushed outwards from the middle of the cart 20 against the front wheels 11. The securing pins 26 enter into a recess or a hole in the rim of the front wheels 11 and thus prevent the front wheels 11 of the wheelchair from rising out of the recesses 25 of the coupling portions 21. The structure and functioning of the securing pins 26 is described in more detail in the following figure.

Fig. 4 shows a vertical sectional view of the cart 20 horizontally relative to the track 30. In this figure, the front wheels 11 of the wheelchair are on top of the cart 20, supported by the wheels 22, in the recesses 25 of the coupling portions 21. The front wheels 11 are secured in place by pushing the securing pins 26 against them. In the example of Fig. 4, the securing mechanism functions so that the securing pins 26 are coupled by a lever mechanism and a wire of a known type as such to the handle 27 located on the vertical support 28 of the cart 20 shown in Figures 1 and 2. The lever mechanism and the wire are not shown in the drawings.

Fig. 5 shows the track 30, which has been formed by first making a groove into the base 31 , such as asphalt paving, into which a guide for an endless chain 33 has been inlaid. In this example, the guide is a slide 35 made of a plastic material located inside a metal channel 34, in the groove 32 of which an endless chain 33 can move. The slide 35 is formed from a bar made of a plastic material, for example, into which the groove for the slide is milled. A preferable characteristic of the plastic bar is that it can be bent into a curved shape so as to fit the groove milled in the base.

Fig. 6 shows a schematic top view of the base 31 paved with asphalt, for example, onto which a loop-shaped track 30 has been formed. The track 30 comprises an endless chain moving in the groove, to which chain the carts 20 are coupled. In Fig. 6, gears 36 are drawn in connection with the track 30 to propel the endless chain and the carts coupled to it. The gears 36 are connected to motor-driven drive apparatuses, which are not shown in the figure. A coupling and decoupling station A for the wheelchairs can also function as a control system for the drive system of the track 30. The drive system is most preferably comprised of an electric motor the rotational speed of which can be adjusted by means of a variable-frequency drive. Thus the speed can always be set at a desired rate. The variable-frequency drive also adjusts the starting and stopping of the chain and the carts to accelerate or decelerate as required. In addition there are various interesting details B and C along the track 30, such as garden plants, a fountain, a fireplace, a canopy, etc.

Fig. 7 shows a cart 20 supported by wheels 22 on a base 31 , engaged with a coupling device 37 of the wheelchair 10 according to another embodiment of the invention. In this embodiment, the coupling device 37 for securing the wheelchair 10 to the cart 20 is provided by a strap retracted from a reel and by a securing member, which can be attached to a suitable location on the frame of the wheelchair 10. The structure of the device 37 corresponds to a safety belt and its securing device as used in vehicles. It is preferable to place the securing member of the strap under the seat of the wheelchair 10, so that the person sitting in the wheelchair 10 cannot accidentally release the securing.

Fig. 8 shows a wheelchair 10 coupled to a cart 20 by means of the coupling device 37 described in Fig. 7. As the figure shows, a strap has been retracted from the coupling device 37 located in the cart 20, with the securing member at the end of the strap secured to the frame of the wheelchair 10, under the seat. The securing member is released in a similar manner as a vehicle seatbelt.

Fig. 9 shows a detail of the track 30 formed by a base 31 and a groove milled therein. In the groove has been placed a plastic slide rail, and therein has also been milled a groove 32, into which a chain 33 has been placed. The chain 33 is propelled by a gear 36, which is rotated by means of a variable-frequency driven electric motor 38 via a transmission chain 39. Fig. 9 shows a bend portion of the track 30, engaged with a chain tensioner 40. Most preferably, the chain tensioner 40 is a pressure-applying piece made of plastic and spring-loaded against the chain 33. As the chain 33 elongates during use, the pressure- applying piece of the chain tensioner 40 moves in the direction of the outside curve. The chain tensioner 40 has a transparent sight glass, through which one can see the position of the pressure-applying piece 40, which directly makes it evident when the chain has to be replaced or serviced due to excessive elongation. Fig. 10 shows a detail of a groove milled into the base 31 , i.e. the asphalt paving of road, wherein there is a slide bar 35 made of plastic material inside a metal channel 34. A chain 33 has been placed in the groove 32 of the slide bar 35, in which chain at least one axle pin 23 is elongated so that the cart 20 pulling the wheelchair 10 can be coupled to it. Fig. 10 shows the axle pin 23 of the chain 33 with a rubber vibration damper 41 connected to it.

Fig. 10 additionally shows that protective flanges 42 made from rubber are installed parallel to the groove to protect the groove milled in the asphalt paving. These protective flanges 42 on both sides of the groove may also be installed so that they touch each other. Thus the groove in the asphalt surface is fully covered, preventing, for example, anyone tripping over it. Additionally, this also prevents rubbish from entering the groove, which could impede the functioning of the chain 33. An asphalt surface prepared in this way corresponds to any road, allowing free traffic by passengers and even vehicles as required. Only an elongated axle pin 23 intended for coupling the cart 10 protrudes at and under each of the carts 10 on the track, through a gap between the protective flanges 42.

ADDITIONAL NOTES

It is obvious to a person skilled in the art that the different embodiments of the invention may vary within the scope of the claims presented below.

LIST OF REFERENCE NUMBERS

10 Wheelchair

11 Front wheel 12 Back wheel

20 Cart

21 Coupling portion

22 Wheel

23 Anchoring member 24 Crosswise recess

25 Recess

26 Securing pin

27 Handle

28 Vertical support 29 Desk

30 Track

31 Base

32 Groove

33 Chain 34 Metal channel

35 Plastic slide

36 Gear

37 Coupling device

38 Electric motor 39 Transmission chain

40 Chain tensioner

41 Vibration damper

42 Protective flange

Claims

1. A method for propelling a wheelchair (10), characterised in that said wheelchair (10) is propelled along an even base (31), such as a road surface, so that said wheelchair is coupled to a cart (20) moving along said base supported by wheels (22), and said cart is propelled by means of a pulling member, such as a chain (33), located in a groove inlaid in said base so that said wheelchair moves along with said pulling member, pulled by said cart.

2. A method according to claim 1 , characterised in that the small front wheels (11) of said wheelchair (10) are placed on top of said cart (20) positioned on said base (31), and as said cart (20) moves on said base (31), it pulls said wheelchair (10) so that the large wheels (12) of said wheelchair rotate freely.

3. A method according to either one of claims 1or2, characterised in that said wheelchair (10) is pulled by means of said cart (20), using the endless chain (33) located in a groove inlaid in said base (31), so that said wheelchair moves along with said chain on a closed circuit track.

4. A method according to any one of claims 1,2 or 3, characterised in that two or more said wheelchairs (10) are pulled along a track (30) at a substantially even speed, and all said wheelchairs (10) engaged with said endless chain are stopped once in a while for a desired period of time at an object (B, C) in connection with the closed circuit track (30).

5. A device for propelling a wheelchair (10), characterised in that said device comprises - a cart (20), to which said wheelchair (10) can be coupled, said cart comprising pivotable wheels (22) so that it can be moved along an even base (31), such as a road surface, and a track (30) formed by said even base (31), such as a road surface, a groove for a pulling member (33) having been inlaid into the surface of said base, - said pulling member (33), which is a moving chain (33) located in said groove inlaid in said base, to which chain said cart (20) is coupled.

6. A device according to claim 5, c h a r a c t e r i s e d in that said cart (20) to be moved along said base (31) has a coupling portion (21), on top of which the small front wheels (11) of said wheelchair (10) can be placed, said coupling portion (21) consists of two parts and can be laterally adjusted according to the distance between said front wheels (11) of said wheelchair (10), and said cart (20) has a coupling device (21 , 37) to secure said wheelchair (10) to said cart, and the large back wheels (12) of said wheelchair (10) remain on said base (31), outside said cart (20).

7. A device according to either one of claims 5 or 6, c h a r a c t e r i s e d in that said cart (20) has most preferably four pivotable wheels (22), and said cart can be moved along said base (31) in the direction of said track (30) supported by said wheels, - said track (30) comprises the circuit-shaped, endless chain loop (33) located in said groove (32) in said base (31), said cart (20) being coupled to said endless chain loop, and there is at least one gear (36), rotatable by a motor, in connection with said groove

(32) in said track (30) to propel the circuit chain (33) and said cart (20) coupled to the chain along said base (31).