WO2008142642A1

WO2008142642A1 - Motor driven stair-climbing device

Info

Publication number: WO2008142642A1
Application number: PCT/IB2008/051979
Authority: WO
Inventors: Hubertus C. A. Dirkx; Nico Wohlfarth
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2007-05-22
Filing date: 2008-05-20
Publication date: 2008-11-27

Abstract

A motor driven stair-climbing device comprises at least a housing (2) and running wheels (3,4) on each side of the housing (2), which housing (2) is tiltable from a normal position to a tilted stair-climbing position. The housing (2) is provided with a stabilising arm (6) on the side remote from the running wheels (3,4), which stabilising arm (6) comprises at least a first arm portion (7) being pivotable connected to the housing (2) and a second arm portion (9) being pivotable connected to the first arm portion (7) at an end of the first arm portion (7) remote from the housing (2), which second arm (9) is provided on an end remote from the first arm (7) with a supporting surface.

Description

Motor driven stair-climbing device

FIELD OF THE INVENTION

The invention relates to a motor driven stair-climbing device comprising a housing and running wheels on each side of the housing, which housing is tiltable from a normal position to a tilted stair-climbing position.

BACKGROUND OF THE INVENTION

By such a device which is known from European patent EP-B 1-0.287.857 is used for moving a wheelchair over a stair whereby the housing is tilted from a normal position to a tilted stair-climbing position by a person standing behind the wheelchair to move the centre of gravity (COG) above the step of the stair to obtain a more stable position of the device on the stairs.

The tilting of the wheelchair is being done by a person, which person is necessary to stabilize the wheelchair on the stair.

SUMMARY OF THE INVENTION

A disadvantage of the motor driving stair-climbing device is that it can not move autonomously and independently along a stair.

It is an object of the invention to provide a motor driven stair-climbing device which is able to climb the stairs itself without assistance of a person. This object is achieved by the motor driven stair-climbing device according to the invention in that the housing is provided with a stabilizing arm, which stabilising arm comprises at least a first arm portion being pivotable connected to the housing and a second arm portion being pivotable connected to the first arm portion at an end of the first arm portion remote from the housing, which second arm is provided on an end remote from the first arm with a supporting surface.

To climb a stair, the stabilizing arm is being driven, whereby the supporting surface is placed on a step of the stair. Then the stair climbing-device is being tilted to a stair- climbing position after which the running wheels are being driven to climb over at least one step. As soon as the stair-climbing device is in a stable position, the stabilizing arm is being pivoted and the supporting surface is being placed on a next step. The driving of the running wheels and the driving of the stabilizing arms is controlled in such a manner that always a stable position of the motor driven stair-climbing device is being obtained whereby the centre of gravity is always positioned above a step and between the running wheels and the stabilizing arm.

An embodiment of the motor driven stair-climbing device according to the invention is characterized in that the arm comprises a suction head provided at the end of the second arm portion remote from the first arm portion, which suction head comprises the supporting surface. Due to the suction head, the motor driven stair-climbing device can be used for vacuum cleaning.

Preferably the housing comprises a flat portion on a side remote from the stabilizing arm, whereby the motor driven stair-climbing device can rest with said flat portion on a step of a stair so that it is possible to vacuum clean the steps of the stair by means of the suction head.

Another embodiment of the motor driven stair-climbing device according to the invention is characterized in that the arm portions comprise a suction tube connected to the suction head.

In this way the arm portions have a double function, namely to stabilize the motor driven stair-climbing device during climbing along a stair and to provide vacuum to the suction head and to remove dust sucked up by the suction head. Due to the double function a relatively compact vacuum cleaning device being able to climb a stair is being obtained.

Yet another embodiment of the motor driven stair-climbing device according to the invention is characterized in that the suction head is provided with breaking means.

Due to the breaking means the supporting surface will rest stable on a step of stair.

A further embodiment of the motor driven stair-climbing device according to the invention is characterized in that the suction head is provided with actuation means. Due to the actuation means the suction head can be moved over the surface of a step in a control manner. Furthermore the suction head can be moved over a flat surface if the motor driven stair-climbing device is only used as a vacuum cleaner. Another embodiment of the motor driven stair-climbing device according to the invention is characterized in that the arm portions are pivotable with respect to the housing at least around axes extending parallel to the axes of the running wheels.

In this manner, the supporting surface of the stabilizing arm can obtain nearly any design position in front of the running wheels, so that the supporting surface can be positioned firm on steps of different kinds of stairs.

Yet another motor driven stair-climbing device according to the invention is characterized in that on each side of the housing at least a pair of running wheels is provided, whereby the running wheels of each pair are pivotably relative to the housing around spaced apart, separate shafts extending parallel to the central axis of the wheels, whereby at least one shaft is eccentrically connected to a disk onto which a running rim of the running wheel is concentrically and rotatably mounted.

By such kind of running wheels, which are known from EP-Bl-0.287.857 the running wheels can be pivoted around the shafts whereby the wheels will be moved with respect to each other whereby a first wheel can be placed on a higher step whilst the second wheel still rests on a lower step. As soon as the first wheel rests stable on the higher step, the lower second wheel will be moved towards the first wheel until the axes of the wheels coincide. Then the running wheels will be moved forwards until they rest against the stair where after the first wheel will be moved upwards again and is placed on the next step. Such pairs of running wheels form a stable and reliable device for climbing stairs.

However, other means for driving the running wheels on such a manner that the running wheels are able to climb a stair are foreseeable.

Preferably the shafts are drivable by at least one climbing motor. Another motor driven stair-climbing device according to the invention is characterized in that the inner wheels of the pair of running wheels are rotatable in one direction only.

This prevents in a relatively simple manner that the wheels role backwards and downwards while climbing the steps. While moving on a flat surface, the inner wheels can be retracted into the housing by driving the shafts, so that the blocked rotation of the inner wheels does not influence the ground mobility of the device when turning and moving backwards. Yet another motor driven stair-climbing device according to the invention is characterized in that at least one wheel is drivable by means of a driving motor to rotate around the central axis.

By rotating the wheel around the central axes, the stair-climbing device can be moved forwards and backwards over a surface. Preferably wheels on both sides of the housing are drivable by separate driving motors so that the device can not only be moved forwards and backwards but can also rotate around a vertical axis. With two driving motors the motor driven stair-climbing device is also able to climb spiral staircases.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in more detail with reference to the drawings in which:

Fig. 1 is a perspective view of the motor driven stair-climbing device according to the invention, Fig. 2a, 2b and 2c are rear views, and a perspective front view respectively of the stair-climbing device shown in fig. 1,

Fig. 3 a, 3b and 3 c are a side view, a rear view and a perspective view of a part of the stair-climbing device according to claim 1,

Fig. 4a, 4b and 4c are a rear view and perspective side views of a part of the stair-climbing device shown in fig. 1,

Fig. 5a and 5b are perspective views of an embodiment of the driving of the outer wheel of the stair-climbing device shown in fig. 1,

Fig. 6a and 6b are perspective views of another embodiment of the driving of an outer wheel of the stair-climbing device shown in fig. 1, Fig. 7 is a plan view of the stabilizing arm of the stair-climbing device shown in fig. 1,

Fig. 8-1 till 8-18 are side views of the climbing sequence of the stair-climbing device shown in fig. 1,

Fig. 9a and 9b are perspective views of the stair-climbing device shown in fig. 1 during vacuum cleaning,

Fig. 10a, 10b- 1Od are a side view and a rear view respectively of the stair- climbing device shown in fig. 1 during vacuum cleaning of a stair,

Fig. 11a and 1 Ib are side views of the stair-climbing device shown in fig. 1 during climbing an open stair, Fig. 12a and 12b are side views of the stair-climbing device shown in fig. 1 during movement over a relatively low object

DETAILED DESCRIPTION OF THE EMBODIMENTS Like parts are indicated by the same numerals in the figures.

Fig. 1 shows a stair-climbing device 1 according to the invention comprising a housing 2, two pairs of running wheels 3, 4 located on opposite sides of the housing 2, a caster wheel 5 located under the housing 2 near the front side thereof and a stabilizing arm 6 connected to the front side of the housing 2. The stabilizing arm 6 comprises a first arm portion 7 pivotably connected to the housing 2 by a first joint 8, a second arm portion 9 pivotably connected to the first arm portion 7 at the end opposite to the housing 2 by a joint 10 and a suction head 11 pivotably connected to the second arm portion 9 at and end opposite to the joint 10 by a joint 12.

Fig. 2a-2c, 3a-3c, 4a-4c show several views partly in a cross-section of the housing 2 and the two pair of wheels 3, 4. Each pair of rolling wheels 3, 4 comprises an inner wheel 13 and an outer wheel 14.

The inner wheels 13 are rotatable around centrically located axes 15 and are pivotable around eccentrically located shafts 16. The shafts 16 are connected to the housing 2. Each outer wheel 14 is rotatable around centrically located axes 17 and are pivotable around eccentrically located shafts 18. The shafts 18 are connected to the housing 2.

The distance between the axes 15 and the shaft 16 is identical to the distance between axes 17 and the shaft 18 and is approximately half the distance between the shafts 16, 18, which are mounted in the housing 2.

The shaft 16 comprises a sprocket wheel 19. The shaft 18 comprises a sprocket wheel 20. The sprocket wheels 19, 20 cooperate with a sprocket wheel 21 rotatable around an axis mounted in the housing 2 and with sprocket wheels 22 mounted on ends of an axis 23 which is also mounted in the housing 2. The axis 23 furthermore comprises a sprocket wheel 24 which cooperates with a sprocket wheel 25 which is driven by a climbing motor 26. The motor 26 as well as the sprocket wheel 25 connected thereto are located in the housing 2. The sprocket wheel 19, 20, 21, 22 are connected to each other by means of a common drive chain Cl. The sprocket wheel 21 ensures a good contact between the drive chain and the sprocket wheels 19, 20 and prevents the drive chain from touching steps of a stair. The sprocket wheels 24, 25 are connected to each other by means of another drive chain C2.

In the housing 2 two driving motors 27 are located which are provided with sprocket wheels 28. On each side of the housing 2 a sprocket wheel 28 is connected by a chain C3 to a sprocket wheel 29 which is rotatably around an axis 30 (see fig. 5, 6). The axis 30 is rotatably located in the tubular shaft 18. The axis 30 is provided with a sprocket wheel 71 which cooperates with a sprocket wheel 72 connected by a chain C4 to the wheel 14 and rotatable around axis 17.

Fig. 5a and 5b show details of another embodiment of an outer wheel 14 comprising a rim wheel 31 which is provided on the inside with sprockets 32 forming an internal sprocket wheel. The outer wheel 14 furthermore comprises a disk 33 which is fixed to the shaft 18 on which the sprocket wheel 20 is mounted. The rim wheel 31 and the disk 17 have the same central axis 17. The axis 30 is provided on a side remote from the sprocket wheel 29 with a sprocket wheel 34 which sprockets match with the sprockets of the inner sprocket wheel 32. By driving the sprocket wheel 34 the rim wheel 31 is rotated around the axis 17 and around the disk 33.

Fig. 6a and 6b show a further embodiment of an outer wheel 14' which differs from the outer wheel 14 in that the rim wheel 35 comprises a sprocket wheel 36 which is rotatable around the axis 17 and which is coupled to the sprocket wheel 34 by means of a chain (not shown). By rotating the sprocket wheels 34, the rim wheel 35 is rotated around axis 17.

Fig. 7 shows a plane view of the stabilizing arm 6. The joint 8 preferably has two degrees of freedom, namely rotation around the X-axis and Y-axis which rotations are controlled by motors (not shown). The joint 10 preferably has one degree of freedom, namely a rotation around the Y-axis, which rotation is preferably controlled by a motor (not shown).

The suction head 11 is preferably connected to the second arm portion 9 by a joint 12 which has three degrees of freedom, namely rotation around the X-axis, Y-axis as well as the Z-axis. In this manner the suction head 11 can reach nearly every location which needs to be cleaned. For the climbing of stair the joints 7, 10, 12 only need to be rotatably around the Y-axis. The stabilizing arm 6 comprises a vacuum hose (not shown) which is connected with one end to the suction head 11 and with an opposite end to a container located in the housing 2. The stair-climbing device 1 further more comprises a number of sensors (not shown) controlled by a processor (not shown) to be able to position the arm portion in the right positions, to position the housing 2 in the inclined position, to be able to recognize a stair and the steps thereof as well as the dimensions of the steps, to be able to balance the device 1 to avoid falling over, to vision the surroundings to avoid crashes with humans and fast moving objects, et cetera.

To energize the several motors 26, 27 as well as to energize the sensors and the processor, the device 1 is provided with a power source, for example a battery (not shown). When the device 1 according to the invention is used to vacuum clean a flat surface, the device 1 is moved around the surface under the control of the processor and the information obtained by the sensors whereby the driving motors 27 are being energized to drive the sprocket wheels 22 and the sprocket wheels 29. By driving the sprocket wheels 29 also the sprocket wheels 34 are being rotated around the axes 30. Due to this rotation the rim wheels 31, 35 of the outer wheels 14, 14' are being rotated around the axes 17. By the processor the amount of rotation as well as the direction of rotation of the both outer wheels 14 are controlled so that the device 1 can be moved to any desired position.

Fig. 8 shows the sequence of climbing a stair 40 comprising a number of steps 41. Each step 41 has a horizontal stepping surface 42 as well as a vertical front surface 43. As soon as the device 1 has cleaned a flat surface 44 and recognize a stair 40 by means of the sensors, the dimensions of the stair 40 are being calculated and the suction head 11 is placed on a horizontal surface 42 of the second step 41 whereby the suction head 11 preferably is positioned against the vertical surface 43 of the third step 41 (see fig. 8-2). The surface of the suction head 11 remote from the second arm portion 9 forms a supporting surface for supporting the device 1. As soon as the suction head 11 has a stable position on the second step, the motors in the joints 8, 10 are controlled to move the device 1 in a climbing position whereby the bottom of the housing 2 includes an angle with the ground surface 44 of about 65°. The pair of wheels 3, 4 are moved forwardly until the wheels rest against the vertical surface 43 of the first step 41 (fig. 8-2). When driving the device 1 over the flat surface 44, the axes 15 and 17 of the inner wheel 13 and the outer wheel 14 preferably coincide or are located relatively close to each other whereby the outer wheel 14 is positioned on the flat surface 44 whilst the inner wheel 13 is positioned a short distance from the surface 44. To climb a step 41 the climbing motor 26 is being activated to pivot the inner wheel 13 and the outer wheel 14 around the shafts 16, 18 in a clockwise direction Pl due to which pivot action the outer wheel 14 is moved to the rear of the housing 2 whilst the inner wheel 13 is moved to the front of the housing 2. Under the control of the sensors and the processor the inner wheel 13 is placed on the horizontal surface 42 of the first step 41 (fig. 8- 3). During the pivoting motions of the inner wheel 13 and the outer wheel 14, also the motors of the stabilizing arms 6 are being controlled to obtain the position shown in fig. 8-3, whereby the second arm portion 9 is preferably controlled in such a manner that it comes to rest against the front side of the third step 41. Due to the tilting of the housing 2 the centre of gravity COG is positioned above a step 41 due to which falling over of the device 1 is being prevented.

As soon as the inner wheels 13 are placed on the horizontal surface 42 of the first step whereby the outer wheels 14 are still positioned on the flat surface 44 and against the vertical surface 43 of the first step, the stabilizing arm 6 is being retracted (see fig. 8-4) and the suction head 11 is placed with its supporting surface on the horizontal surface 42 of the third step 41 (see fig. 8-5). Then the motors of the stabilizing arm 6 are energized to move the arm portions 7, 9 and therefore the housing 2 to the position as shown in fig. 8-6 whereby the centre of gravity COG is located more near the front of the device 1. Then the climbing motor 26 is activated again to pivot the inner wheels 13 and the outer wheels 14 around the shafts 16, 18 from a position shown in fig. 8-7 to position shown in fig. 8-8, whereby the axes 15, 17 of the wheels 13, 14 coincide. The driving motors 27 are now energized to move the housing 2 forwardly until the wheels 13, 14 rest against the vertical surface 43 of the second step 41. The device 1 is now in the same position as shown in fig. 8-2. The sequence as shown in fig. 8-2 till 8-9 is now repeated until the last step 41 of the stair 40 is reached (fig. 8-12). From this position this stabilizing arm 6 is controlled in such a manner that the inner wheels and outer wheels 13, 14 are pivoted (fig. 8-13 and fig. 8-14) to the position as shown in fig. 8-15 whereby the axes 15 and 17 of the wheels 13, 14 coincide or nearly coincide. The stabilizing arm 6 is then controlled to lowering the housing 2 from the tilted position (fig. 8- 16, fig. 8-17) to a normal position (fig. 8-18) in which position the device 1 is again located on a flat surface 44.

Fig. 9a and 9b show a tilted position of the housing 2 whereby the tilting is being obtained by actuating the climbing motor 26. In this position of the device 1 the suction head can be used to vacuum clean other surfaces then the flat surface 44 on which the device 1 is positioned, for example steps 42 of stairs, part of the surrounding walls, etc.. For cleaning the walls it might be possible to replace the suction head 11 by another kind of cleaning head.

To be able to vacuum clean all the steps 41 of the stair 40 the housing 2 preferably has a flat rear side 50 by means of which the housing 2 can rest on a horizontal surface 42 on a step 41 (see fig. 10a). In this position the stabilizing arm 6 can be controlled to move the suction head 11 over several steps 40. To facilitate the cleaning of the whole steps 40 the housing 2 is preferably provided at the flat rear side 50 with motor driven wheels 51 by means of which the housing 2 can be moved in the direction indicated by the double arrow Pl over the horizontal surface 42 of step 41 (see fig. 1 Ob-I Od). As shown in fig. 1 Ia-I Ib the device 1 according to the invention can also be used to climb open stairs 52 which stairs 52 do comprise horizontal surfaces 53 but do not comprise vertical surfaces. By such kind of stairs 52 the stabilizing arm 6 is controlled in such a manner that the suction head 11 is positioned on the horizontal surface 53 of the step remote from the housing 2 whereby the second arm portion 9 rests against a front side 54 on the horizontal surface 53 (fig. 1 Ia). It is also possible to position the suction head 11 in the middle of a horizontal surface 53 whereby the second arm portion 9 obtains an almost vertical position in which it rests against the front part 54 of a horizontal surface 53 (fig. l ib).

Fig. 12a and 12b show the use of the device 1 according to the invention whereby an obstacle (not shown) on the flat surface 44 might hinder the caster wheel 5. As shown in fig. 12a the stabilizing arm 6 is controlled so that the front side of the housing 2 as well as the caster wheel 5 is moved upwardly, after which the wheels 13, 14 are controlled to "walk over" the obstacle (fig. 12).

It is possible to provide the device according the invention with another kind of running wheels which are able to climb stairs.

It is also possible to use a separate vacuum hose and suction head and a separate stabilizing arm.

It is also possible to use the device 1 for other functions then vacuum cleaning, for example cleaning tables, serving something to a person with an added roboted hand, open and close doors, etc..

It is also possible to position the stabilizing arm 6 on the rear side of the device 1 whereby the stabilizing arm 6 stabilizes the device 1 on steps which are located below the housing 2 in stead of above.

It is also possible to use a driving belt in stead of a driving chain. It is also possible to provide the stabilizing arm 6 with telescopic parts or with more arm portions.

A motor driven stair-climbing device comprises at least a housing and running wheels on each side of the housing, which housing is tiltable from a normal position to a tilted stair-climbing position. The housing is provided with a stabilising arm on the side remote from the running wheels, which stabilising arm comprises at least a first arm portion being pivotable connected to the housing and a second arm portion being pivotable connected to the first arm portion at an end of the first arm portion remote from the housing, which second arm is provided on an end remote from the first arm with a supporting surface. While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1. Motor driven stair-climbing device comprising at least a housing and running wheels on each side of the housing, which housing is tiltable from a normal position to a tilted stair-climbing position, characterized in that the housing is provided with a stabilising arm, which stabilising arm comprises at least a first arm portion being pivotable connected to the housing and a second arm portion being pivotable connected to the first arm portion at an end of the first arm portion remote from the housing, which second arm is provided on an end remote from the first arm with a supporting surface.

2. Motor driven stair-climbing device according to claim 1, characterized in that the arm comprises a suction head provided at the end of the second arm portion remote from the first arm portion, which suction head comprises the supporting surface.

3. Motor driven stair-climbing device according to claim 2, characterized in that the arm portions comprise a suction tube connected to the suction head.

4. Motor driven stair-climbing device according to claim 2 or 3, characterized in that the suction head is provided with breaking means.

5. Motor driven stair-climbing device according to one of the proceeding claims 2-4, characterized in that the suction head is provided with actuation means.

6. Motor driven stair-climbing device according to one of the proceeding claims, characterized in that the arm portions are pivotable with respect to the housing at least around axes extending parallel to the central axes of the running wheels.

7. Motor driven stair-climbing device according to one of the proceeding claims, characterized in that on each side of the housing at least a pair of running wheels is provided, whereby the running wheels of each pair are pivotably relative to the housing around spaced apart, separate shafts extending parallel to the central axis of the wheels, whereby at least one shaft is eccentrically connected to a disk onto which a running rim of the running wheel is concentrically and rotatably mounted.

8. Motor driven stair-climbing device according to claim 7, characterized in that the shafts are drivable by at least one climbing motor.

9. Motor driven stair-climbing device according to claim 7 or 8, characterized in that the inner wheels of the pair of running wheels are rotatable in one direction only.

10. Motor driven stair-climbing device according to one of the proceeding claims

7-9, characterized in that at least one wheel is drivable by means of a driving motor to rotate around the central axis.

11. Motor driven stair-climbing device according to one of the proceeding claims 7-10, characterized in that at least one outer wheel is drivable by the driving motor to rotate around the central axis, whereby the driving motor is coupled to said outer wheel by means of at least one sprocket wheel rotatable around the shaft.

12. Motor driven stair-climbing device according to claim 11, characterized in that the outer wheel is provided with a sprocket wheel rotatable around the central axis, which is drivable by means of the sprocket wheel rotatable around the shaft.

13. Motor driven stair-climbing device according to claim 11, characterized in that the outer wheel is provided with an internal sprocket wheel which surrounds and is coupled to the sprocket wheel rotatable around the shaft.

14. Motor driven stair-climbing device according to one of the proceeding claims, characterized in that the stair-climbing device is provided with sensors.