EP3196159B1

EP3196159B1 - Stairlift apparatus

Info

Publication number: EP3196159B1
Application number: EP17151526.5A
Authority: EP
Inventors: Ross LOTHIAN
Original assignee: Stair Assist Ltd
Current assignee: Stair Assist Ltd
Priority date: 2016-01-23
Filing date: 2017-01-13
Publication date: 2023-10-04
Anticipated expiration: 2037-01-13
Also published as: GB201601263D0; EP3196159C0; EP3196159A1

Description

Field of the Invention

The present invention relates to improved stairlift apparatus and to a stairlift arrangement comprising such improved stairlift apparatus.

Background Art

Stairlifts are known. A known stairlift typically comprises a rail which is mounted to a stair such that the rail extends between the top and bottom of the stair. The known stairlift further comprises a seat which is mechanically coupled to the rail so as to allow for movement of the seat along the rail. The seat usually has arms and a footrest. An electric motor is operative to drive the seat along the rail.
Each of WO 2013/079922 A1 and WO 2006/051316 A1 discloses a stairlift apparatus comprising a rail mountable chassis, a seat mounted on the chassis and a hand support mounted on the chassis. EP 0 564 177 A1 discloses a stairlift apparatus according to the preamble of claim 1.
The present inventors have recognised that known stairlifts have shortcomings. The present invention has been devised in light of the inventors' appreciation of such shortcomings. It is therefore an object for the present invention to provide improved stairlift apparatus comprising a seat configured to support a person when the stairlift apparatus is in use. It is a further object for the present invention to provide a stairlift arrangement comprising a rail which is mounted to and extends up a stairway and improved stairlift apparatus mechanically coupled to the rail so as to provide for movement of the seat along the rail.

Statement of Invention

According to the present invention there is provided stairlift apparatus according to claim 1. Particular embodiments are set out in the dependent claims.
The stairlift apparatus comprises a chassis which is configured to be mechanically coupled to a rail mounted on a stairway whereby, during use, the chassis moves along the rail such that the chassis moves up and down the stairway. The stairlift apparatus further comprises a seat mounted on the chassis. The seat is configured to support a person when the stairlift apparatus is in use and more specifically to bear the weight of the person when the stairlift apparatus is in use. Therefore the seat carries the person up and down stairs. The stairlift apparatus yet further comprises a hand support mounted on the chassis. The hand support has a hand grippable portion. The stairlift apparatus is configured such that during use a person is one of carried up or down stairs when supported by the seat and aided by gripping the hand support when walking up or down stairs. Therefore the hand support provides support for the person as he or she progresses on foot up or down the stairs. At one time a person may sit in the seat and be carried up or down the stairs. At another time the person may ascend or descend the stairs on foot while gripping the hand support to thereby gain support.
The stairlift apparatus may be configured such that it is changeable between a first disposition in which a person is carried up or down stairs when supported by the seat and a second disposition in which a person is aided up or down stairs by gripping the hand support when on foot. At least one of the seat and the hand support may be changeable between the first and second dispositions. More specifically each of the seat and the hand support may be movable between the first and second dispositions. For example, the seat may be movable from the first disposition to provide sufficient room for a person to grip the hand support when ascending or descending stairs on foot without the seat impeding movement of the person. By way of further example, the hand support may be movable between the first and second dispositions such that the grippable portion is moved between a height appropriate for a person sitting in the seat and a height appropriate for a person ascending or descending stairs on foot. The stairlift apparatus may be configured for movement between the first and second dispositions by a mechanical drive arrangement. The mechanical drive arrangement may be under user control whereby the stairlift apparatus may be moved readily between the first and second dispositions. Movement between the first and second dispositions may thus be accomplished by the user and without the involvement of the like of an engineer. The mechanical drive arrangement is described further below.
The stairlift apparatus is configured such that the seat faces the direction of travel during use of the stairlift apparatus. More specifically the seat may be oriented on the chassis such that the seat faces along the rail when the chassis is mounted on the rail. Therefore the seat may be oriented appropriately in relation to a rail coupling arrangement comprised in the stairlift apparatus, the rail coupling arrangement being configured to be mechanically coupled to a rail mounted on a stairway. Having a seat that faces the direction of travel may provide for ease and safety of use. After a person is carried up a stair a forward facing seat allows the person to step readily and safely onto the landing. Conversely, a forward facing seat allows the person to step readily and safely onto the floor after a person is carried down a stair.
The stairlift apparatus may be configured such that the seat is changeable between first and second seat dispositions. The seat faces in a first direction in the first seat disposition and the seat faces in a second, opposite direction in the second seat disposition. Changing between the first and second seat dispositions allows a person who is seated in the seat to face in the direction of travel when being carried up the stairs and to face in the direction of travel when being carried down the stairs.
The seat comprises a first portion on which the person sits or perches and a second portion which provides support for the back of the person. Adjacent edges of the first and second portions are mechanically coupled for rotation of the first and second portions in relation to each other. The first and second portions may define an angle between them which faces in the first direction in the first seat disposition and the first and second portions may define an angle between them which faces in the second direction in the second seat disposition, with change between the first and second seat dispositions being by way of rotation of the first and second portions in relation to each other. The first and second portions may be at an angle of about 90 degrees when in each of the first and second seat dispositions. The first and second portions may be rotated progressively in relation to each other. As described further below, rotation of the first and second portions such that they define an obtuse angle may allow a person using the apparatus to perch rather than sit on the seat. The stairlift apparatus may be configured for movement of the seat between the first and second seat dispositions by a mechanical drive arrangement. The mechanical drive arrangement may be under user control. Alternatively or in addition, the mechanical drive arrangement may be operable without user control to change between the first and second seat dispositions. More specifically the mechanical drive arrangement may be operable to change from the first to the second seat disposition when the stairlift apparatus reaches the top of the stair and to change from the second to the first seat disposition when the stairlift apparatus reaches the bottom of the stair. The stairlift apparatus may thus ready itself for next use.
The stairlift apparatus may be configured such that the seat may be rotatable in relation to the chassis and more specifically rotatable about a horizontal axis which is substantially orthogonal to the direction of travel. The seat may be rotatable about an axis adjacent a distal end of the first portion of the seat. The first portion of the seat may be rotatably coupled to the second portion of the seat adjacent a proximal end. The height of the seat and more specifically the inclination of the first portion of the seat may thus be changed whereby the seat may be moved between a position appropriate for sitting and a position appropriate for perching. Changing the inclination and height of the seat may be advantageous when a person is seating him or herself on the seat before being carried and when rising from the seat after being carried. More specifically the seat height and inclination may change progressively during sitting and rising. The stairlift apparatus may be configured accordingly and more specifically in respect of the drive arrangement as described below. In addition, changing the inclination of the seat may reduce the space taken up by the stairlift apparatus when not in use.
The stairlift apparatus further comprises a seat support arm. The seat support arm is mechanically coupled to the seat to thereby support the seat. Furthermore the seat support arm is mechanically coupled to the chassis. The seat support arm is mechanically coupled for rotation in relation to the chassis at a first location. The seat support arm is mechanically coupled to the seat at a second location. The first and second locations are spaced apart along the seat support arm. The first location may be towards a proximal end of the seat support arm. The second location may be towards a distal end of the seat support arm. The seat support arm is mechanically coupled to the seat at the second location for rotation of seat support arm and seat in relation to each other.
Where the seat comprises first and second portions which are rotatable in relation to each other, the seat may be configured such that the first and second portions are rotatable such that they are overlying thereby reducing the space occupied by the seat. Furthermore the stairlift apparatus may be configured such that the seat is rotatable in relation to the chassis and more specifically is rotatable about a vertically extending axis. Rotation of the seat about the axis when the first and second portions are overlying may reduce the space occupied by the stairlift apparatus when the stairlift apparatus is not in use. Furthermore rotation of the seat about the axis when the first and second portions are overlying may provide for ease of use of the hand support when the stairlift apparatus is in the second disposition.
The hand grippable portion may be elongate in form. The hand grippable portion may be substantially cylindrical along at least part of its length. The hand support may comprise a base portion mounted on the chassis. The hand grippable portion may extend from the base portion. The base portion and more specifically a proximal end of the base portion may be mounted for rotation in relation to the chassis. Rotation of the base portion in relation to the chassis may provide for movement between the first and second dispositions. The base portion may be mounted for rotation in relation to the chassis about a horizontal axis which is orthogonal to the direction of travel. The hand grippable portion may extend from a distal end of the base portion whereby the hand grippable portion describes an arc upon rotation of the base portion in relation to the chassis. At least one of the height of the hand grippable portion and a fore and aft position of the hand grippable portion may thus be changed. The hand grippable portion may be lower when a person is sitting and higher when a person is using the hand grippable portion as support when walking. Changing the height and the fore and aft position of the hand grippable portion of the hand grippable portion may be advantageous when a person sits down on the seat before being carried and when rising from the seat after being carried. More specifically the height and the fore and aft position may change progressively during sitting and rising. For example, the height of the hand grippable portion may reduce progressively and the hand grippable portion may move progressively closer towards the seat when a person sits to thereby provide assistance to the person. By way of another example, the height of the hand grippable portion may increase progressively and the hand grippable portion may move progressively away from the seat when a person rises from the seat to thereby provide assistance to the person. The stairlift apparatus may be configured accordingly and more specifically in respect of the drive arrangement as described below.
The hand grippable portion may extend orthogonally from a distal end of the base portion. The hand grippable portion may be rotatable in relation to the base portion and more specifically may be rotatable about an axis substantially parallel to the direction of travel. The hand grippable portion may therefore be moved between an in use position in which the hand grippable portion extends horizontally and more specifically across the front of the seat and an out of use position in which the hand grippable portion extends vertically. The hand grippable portion may be moved through substantially 90 degrees between the in use and the out of use positions. The hand grippable portion may be moved to the out of use position when a person wishes to gain unimpeded access to the seat or to reduce the space occupied by the stairlift apparatus when the stairlift apparatus is not in use.
The stairlift apparatus may be configured such that it is changeable between a third disposition and the first and second dispositions. The third disposition may be such that a person may perch on the seat. Perching may involve the person resting on the seat without being fully seated such that his or her weight is not fully supported by the seat and with the seat being at a height such that the person's legs are more extended than they would be if the person were fully seated. A configuration which allows for perching may be advantageous for someone who has difficulty in bending his or her knees properly. The seat may be higher in the third disposition than in the first disposition. The height of the seat may be changed as described above and more specifically in respect of operation of the seat support arm. The first portion of the seat may be at an incline in the third disposition and substantially level in the first disposition. The inclination of the first portion of the seat may be changed as described above and more specifically in respect of operation of the seat support arm. The height of the hand support may change between the third disposition and the first disposition. More specifically the hand support may be higher when in the third disposition than when in the first disposition. The hand support may be at substantially the same height when in the second and third dispositions. The height of the hand support may be changed as described above and more specifically in respect of operation of the base portion. As mentioned above, change between dispositions is by way of a mechanical drive arrangement which may be under user control.
The stairlift apparatus further comprises a drive arrangement which is operative to change the stairlift apparatus between dispositions. The stairlift apparatus may be configured such that the drive arrangement moves the seat and the hand support and more specifically moves the seat and the hand support in a synchronised fashion. The drive arrangement comprises a drive motor and more specifically an electric drive motor. The drive motor is mounted on the chassis. An output from the drive motor is mechanically coupled to at least one of the seat and the hand support and more specifically may be coupled to both the seat and the hand support.
The drive arrangement comprises a force transmitting arrangement and more specifically a drive train which is operable to transmit force from the drive motor to at least one of the seat and the hand support. The force transmitting arrangement may comprise a first rotating element, such as a pulley, mounted on the drive motor. The force transmitting arrangement further comprises a second rotating element mounted on the seat. The force transmitting arrangement may further comprise a drive belt disposed to transmit motion of the first rotating element to the second rotating element. Rotation of the second rotating element may change at least one of the height and the inclination of the seat. The force transmitting arrangement may further comprise a third rotating element mounted on the hand support and a drive belt disposed to transmit motion of the first rotating element to the third rotating element. Rotation of the third rotating element may cause the distal end of the base portion to describe an arc as described above. Rotation of the first rotating element may therefore cause rotation of both the second rotating element and the third rotating element.
Where the drive arrangement drives both the seat and the hand support, the force transmitting arrangement may be configured such that the seat rotates about an axis through a predetermined number of degrees less than the hand support rotates about its axis. Configuring the force transmitting arrangement in this fashion may reduce the likelihood of a person being crushed between the seat and the hand support. Further to the second rotating element the force transmitting arrangement may comprise a fourth rotating element. The fourth rotating element may be mechanically coupled to the seat. The fourth rotating element may be configured to engage with the second rotating element such that the second rotating element rotates the fourth rotating element but by the predetermined number of degrees less than rotation of the second rotating element. One of the second rotating element and the fourth rotating element may define an aperture therethrough and other of the second rotating element and the fourth rotating element may be configured to be received at least in part in the aperture. The surface of the aperture and the surface of the part received therethrough may define cooperating profiles which provide for rotation by less than the predetermined number of degrees. More specifically one of the surface of the aperture and the surface of the part received therethrough may define a protrusion and the other of the surface of the aperture and the surface of part received therethrough may define a recess, the protrusion being received in the recess. The recess may extend circumferentially whereby the protrusion may move to and fro in the recess. The length of the recess may determine the predetermined number of degrees.
The stairlift apparatus comprises a seat support arm. The second rotating element is mounted at a first location on the seat support arm and the force transmitting arrangement further comprises a seat rotating element mounted on the seat support arm at a second location spaced apart from the first location. The first and second locations may be towards opposite ends of the seat support arm. The force transmitting arrangement further comprises a drive belt disposed to transmit motion of the second rotating element to the seat rotating element. The seat comprises first and second portions which are rotatable in relation to each other. The seat rotating element is mechanically coupled to the seat so as to provide for rotation of the first portion in relation to the second portion, whereby the inclination of the second portion may be changed.
As mentioned above, the stairlift apparatus may be user controllable. The stairlift apparatus may therefore comprise a control arrangement. The control arrangement may comprise a user operable control which, for example, comprises push buttons or a contact sensitive switch. The user operable control may be comprised in the hand support whereby the user operable control is readily accessible and operable by a user. As described below, stairlift apparatus is moved up and down a stair by way of a traction motor. The hand support may be configured such that the user operable control is actuated when a person grips the hand grippable portion. The stairlift apparatus may be configured such that such actuation of the user operable control causes operation of the traction motor and relaxation of grip on the hand grippable portion causes such actuation of the user operable control to cease. The stairlift apparatus therefore moves up or down the stairs only when the person grips the hand grippable portion.
The stairlift apparatus may further comprise a footrest mounted on the chassis. The footrest may be mounted on the chassis at a location spaced apart from the seat whereby a person sitting on the seat may rest his or her feet on the foot rest. The footrest may comprise a plate which may be of generally rectangular outline. The plate may be rotatably coupled to the chassis. The plate may rotate in relation to the chassis about an axis which is substantially parallel to a direction of travel. The plate may therefore be rotated between an in use position and a stored position. Movement of the plate to the stored position may reduce the space occupied by the stairlift apparatus when the stairlift apparatus is not in use. Furthermore movement of the plate to the stored position may provide for ease of use of the hand support when the stairlift apparatus is in the second disposition. The stairlift apparatus may comprise a footrest motor mounted on the chassis and more specifically an electric footrest motor. The footrest motor may be mechanically coupled to the footrest whereby the footrest may be rotated.
The chassis may comprise a main support member. The main support member may have the form of an elongate plate. The stairlift apparatus may be configured such that the elongate plate is vertically disposed along its length. The main support member may be mechanically coupled to at least one of the seat and the hand support. The main support member may be mechanically coupled to at least one of the footrest and the drive arrangement. The main support member may be mechanically coupled to the traction arrangement described below.
The stairlift apparatus may further comprise a traction arrangement. The traction arrangement may be mounted on the chassis. The traction arrangement may comprise a traction motor and more specifically an electric traction motor. The traction arrangement may further comprise a traction coupling arrangement which is configured to mechanically engage with a rail mounted on a stair so as to draw the stairlift apparatus along the rail when the stairlift apparatus is in use. The traction motor may be coupled mechanically to the traction coupling arrangement.
According to a second aspect of the present invention there is provided a stairlift arrangement according to claim 14 which comprises stairlift apparatus as defined by claims 1 to 13.
The stairlift arrangement may comprise first and second rails. The first and second rails may be spaced apart from each other and substantially parallel. The stairlift apparatus may be configured to mechanically couple to each of the first and second rails.

Brief Description of Drawings

Further features and advantages of the present invention will become apparent from the following specific description, which is given by way of example only and with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a stairlift arrangement comprising stairlift apparatus according to the present invention when in the seated disposition;
Figure 2 is a perspective view of the stairlift arrangement of Figure 1 when the stairlift apparatus is in the perching disposition;
Figure 3 is a perspective view of the stairlift arrangement of Figure 1 when the stairlift apparatus is in the supported walking disposition;
Figure 4 is a perspective view of the stairlift arrangement of Figure 1 when the stairlift apparatus is in the stored disposition;
Figure 5 is a perspective view of the drive arrangement of the stairlift apparatus of Figure 1;
Figure 6 is an exploded perspective view of components of the drive arrangement of Figure 5 operable to move the hand support of the stairlift apparatus; and
Figure 7 is an exploded perspective view of components of the drive arrangement of Figure 5 operable to move the seat of the stairlift apparatus.

Description of Embodiments

A perspective view of a stairlift arrangement 10 comprising stairlift apparatus 12 according to the present invention when in the seated disposition is shown in Figure 1. Further to the stairlift apparatus 12 the stairlift arrangement 10 comprises first and second rails 14, 16 which are vertically spaced apart from each other and mounted at the side of a stairway (not shown). The stairlift apparatus 12 comprises a chassis 18, a seat 20 and a hand support 22. Each of the seat 20 and the hand support 22 is mounted on the chassis 18. The seat comprises a first portion 24 on which a person sits when in the disposition shown in Figure 1 and a second portion 26 which provides support for the back of the seated person. Adjacent edges of the first and second portions 24, 26 are hingedly coupled to each other whereby first and second portions are rotatable in relation to each other. As can be seen from Figure 1, the first and second portions 24, 26 are rotated relative to each other such that they define an angle between them of substantially 90 degrees whereby the seat is configured such that it can support the weight of a person sitting in the seat. The chassis 18 comprises an elongate support member 28 which is in the form of a plate of generally rectangular form. The elongate support member 28 is vertically disposed along its length. The stairlift apparatus 12 also comprises a footrest 30 which is in the form of a plate of generally rectangular form. The footrest 30 is attached to the lower end of the elongate support member 28 by way of a hinged coupling. The stairlift apparatus 12 further comprises an electric footrest motor (not shown) which is mechanically coupled to the footrest 30 whereby the footrest may be raised and lowered.
The stairlift apparatus 12 yet further comprises a seat support arm 32. The seat support arm 32 is elongate in form and is rotatably coupled towards a proximal end to the elongate support member 28 midway along the elongate support member 28. The seat support arm 32 is also rotatably coupled towards a distal end to the side of the seat 20 where the first and second portions 24, 26 are hingedly attached to each other. The seat support arm 32 defines an upwardly oriented slot 34 on its seat facing side. A cylindrical member 36 extends from a seat support arm 32 facing edge of the distal end of the first portion 24 of the seat. The cylindrical member 36 is of a diameter which allows the cylindrical member 36 to be received in the slot 34 defined in the seat support arm 32. The distal end of the first portion 24 of the seat is thus supported when the cylindrical member 36 is received in the slot 34 defined in the seat support arm 32 whereby the first portion 24 of the seat can bear the weight of a person sitting in the seat. The seat support arm 32 and the drive arrangement therefor are described in more detail below with reference to Figures 5 and 7.
The hand support 22 of Figure 1 comprises a hand grippable portion 38 which is elongate in form and of cylindrical cross-section along its length. The hand grippable portion 38 is shaped to define two hand grips 40 towards opposite ends. The hand grippable portion 38 comprises user operable controls 42 which are disposed so as to be readily operable when the two hand grips 40 are gripped by a person seated in the seat 20. The user operable controls 42 provide for electrical control of the stairlift apparatus 12 such as in respect of changing between the different dispositions. The hand support 22 further comprises a base portion 44. The proximal end of the base portion 44 is mounted for rotation towards an upper end of the elongate support member 28. Rotation is about a horizontal axis which is orthogonal to the direction of travel. The hand grippable portion 38 extends orthogonally from a distal end of the base portion 44 across the front of the seat 20 whereby the hand grippable portion describes an arc upon rotation of the base portion in relation to the elongate support member 28. The hand support 22 and the drive arrangement therefor are described in more detail below with reference to Figures 5 and 6. The stairlift apparatus 12 further comprises an electric drive motor 46 which is mounted on the side of the elongate support member 28 facing away from the seat 20 towards a lower end of the elongate support member 28 and which is operable, as described below, to drive both the seat 20 and the hand support 22. The stairlift apparatus 12 yet further comprises an electric traction motor 48 which is mounted on the side of the elongate support member 28 facing away from the seat 20 towards an upper end of the elongate support member 28. The stairlift apparatus 12 also comprises a traction coupling arrangement of known form and function which is driven by the traction motor 48 and which is operative to mechanically engage with the second rail 16 and to draw the stairlift apparatus 12 along the second rail 16.
A perspective view of the stairlift arrangement 10 of Figure 1 when the stairlift apparatus 12 is in the perching disposition is shown in Figure 2. Components of the view shown in Figure 2 in common with the view shown in Figure 1 are designated with like reference numerals. The reader's attention is directed to the description provided above with reference to Figure 1 in respect of such common components. Differences between the view shown in Figure 1 and the view shown in Figure 2 will now be described. As can be seen from Figure 2, the seat support arm 32 has been rotated forwards to an angle of about 45 degrees to the vertical. As a result, the distal edge of the first portion 24 of the seat has been raised slightly and the proximal edge of the first portion 24 of the seat has been raised to a greater extent whereby the first portion 24 is inclined by about 45 degrees to the vertical. The coupling of the seat support arm 32 adjacent where the first and second portions 24, 26 are hingedly attached to each other is such that the second portion 26 of the seat remains substantially vertical. Furthermore, the base portion 44 has rotated forwards through about 90 degrees whereby the base portion 44 extends substantially vertically from the top of the elongate support member 28. As a result, the hand support 22 has described an arc from the position shown in Figure 1 whereby the hand support 22 is now higher and has moved away from the second portion 26 of the seat. It is to be noted that the base portion 44 and the seat 20 move in a synchronised fashion as will become apparent from the description provided below with reference to Figure 5.
The disposition shown in Figure 2 is suitable for a person who wishes to perch on the seat 20. Perching involves the person resting on the seat without being fully seated such that his or her weight is not fully supported by the seat and with the seat being at a height such that the person's legs are more extended than they would be if the person were fully seated. This disposition is advantageous for someone who has difficulty in bending his or her knees properly. Figure 2 is also illustrative of operation of the stairlift apparatus 12 when a person is sitting down on the seat before being carried and when a person is rising up from the seat after being carried. After a person has been carried, the seat 20 and the hand support 22 move progressively from the position shown in Figure 1 to the position shown in Figure 2 whereby the person is raised up. The person then lifts up the hand grippable portion 38 whereby the hand grippable portion 38 no longer impedes his or her forward movement from the stairlift apparatus 12. Configuration of the hand support 22 for lifting up of the hand grippable portion 38 is described below with reference to Figure 4. Before a person is carried by the stairlift apparatus 12, the stairlift apparatus 12 has the disposition shown in Figure 2 but with the hand grippable portion 38 lifted up. The person perches on the seat 20 and then lowers the hand grippable portion 38. The seat 20 and the hand support 22 then move progressively from the position shown in Figure 2 to the position shown in Figure 1 whereby the person is lowered to the seated position.
A perspective view of the stairlift arrangement of Figure 1 when the stairlift apparatus is in the supported walking disposition is shown in Figure 3. Components of the view shown in Figure 3 in common with the view shown in Figure 1 are designated with like reference numerals. The reader's attention is directed to the description provided above with reference to Figure 1 in respect of such common components. Differences between the view shown in Figures 1 and 2 and the view shown in Figure 3 will now be described. As can be seen from Figure 3, the footrest 30 has been raised by way of operation of the footrest motor. Also the distal edge of the first portion 24 of the seat has been raised such that the first and second portions 24, 26 are adjacent and overlying. The distal edge of the first portion 24 of the seat is raised manually. The disposition shown in Figure 3 is appropriate for aiding a person who is ascending stairs on foot. The person stands on the floor between the folded first and second portions 24, 26 of the seat and the hand grippable portion 38. The folded first and second portions 24, 26 of the seat provide support for the person's back. The person then grips the hand grippable portion 38 to provide support and by way of the user operable controls 42 causes the stairlift apparatus 12 to be drawn along the rails 14, 16 whereby the stairlift apparatus 12 travels up the stairs. When the top of the stairs is reached movement of the stairlift apparatus 12 ceases and the person lifts up the hand grippable portion 38 and walks away from the stairlift apparatus.
The stairlift apparatus 12 of Figures 1 to 3 is configured for reversal of the seat 20. Reversal of the seat involves the seat support arm 32 rotating further forward such that it is on the opposite side of the elongate support member 28. For example, the seat support arm 32 shown in Figure 3 rotates through a further 90 degrees so it is at an angle of 45 degree to the vertical on the opposite side of the elongate support member 28. By way of further example, the seat support arm 32 shown in Figure 1 rotates 180 degrees so it is still horizontal but on the opposite side of the elongate support member 28. Reversal of the seat happens when either the top or bottom of the stairs is reached and without user operation whereby the stairlift apparatus 20 is ready for next use. Although not shown in Figures 1 to 3, the seat support arm 32 comprises a latch of conventional form and function which is operative to hold the cylindrical member 36 in the slot 34. When the seat 20 of Figure 1 reverses the latch holds the cylindrical member 36 in the slot 34. When a user wishes to lift the distal edge of the first portion 24 so the seat is in the same disposition as shown in Figure 3, the latch is operative to allow the cylindrical member 36 to be removed from a slot (not shown) which extends from an opposite side of the seat support arm 32 to the side from which the shown slot 34 extends.
A perspective view of the stairlift arrangement of Figure 1 when the stairlift apparatus is in the stored disposition is shown in Figure 4. Components of the view shown in Figure 4 in common with the view shown in Figure 1 are designated with like reference numerals. The reader's attention is directed to the description provided above with reference to Figure 1 in respect of such common components. Differences between the view shown in Figure 3 and the view shown in Figure 4 will now be described. As can be seen from Figure 4, the footrest 30 remains raised. The seat 20 has been rotated towards the elongate support member 28 about a vertically extending axis by way of a first joint 60 in the arrangement coupling the seat 20 to the distal end of the seat support arm 32. In addition, a part of the hand grippable portion 38 beyond the hand grip 40 nearer the elongate support member 28 has been rotated about an axis substantially parallel to the direction of travel by way of a second joint 62 therein whereby the rotated part of the hand grippable portion 38 extends upwards. Movement of the seat 20 and the hand grippable portion 38 in this fashion reduces the space occupied by the stairlift apparatus 12 when the stairlift apparatus is not in use. The second rail 16 can be used as a handrail when the stairlift apparatus is in the stored disposition of Figure 4.
A perspective view of the drive arrangement of the stairlift apparatus of Figure 1 is shown in Figure 5. Components of the view shown in Figure 5 in common with the views shown in Figures 1 and 4 are designated with like reference numerals. The reader's attention is directed to the description provided above with reference to Figures 1 and 4 in respect of such common components. A first pulley 80 is mounted on the drive motor 46 so as to rotate with the drive motor. A second pulley arrangement 82 is mounted on the side of the seat support arm 32. A first toothed drive belt 84 engages with corresponding teeth defined on each of the first pulley 80 and the second pulley arrangement 82 whereby motion of the first pulley is transmitted to the second pulley arrangement. The height and inclination of the seat is thus changed as described above. The part of the drive arrangement comprised in the seat support arm 32 is described below with reference to Figure 7. A third pulley arrangement 86 is mounted on the proximal end of the base portion 44. A second toothed drive belt 88 engages with corresponding teeth defined on each of the first pulley 80 and the third pulley arrangement 86 whereby motion of the first pulley is transmitted to the third pulley arrangement. The hand support 22 is thereby moved through an arc as described above. The second and third pulley arrangements 82, 86 are both driven by the drive motor 46 by way of the first pulley 80 whereby movement of the seat 20 and the hand support 22 is synchronised.
An exploded perspective view of components of the drive arrangement of Figure 5 operable to move the hand support 22 of the stairlift apparatus 12 is shown in Figure 6. Components of the view shown in Figure 6 in common with the views shown in Figures 1 to 5 are designated with like reference numerals. The reader's attention is directed to the description provided above with reference to Figures 1 to 5 in respect of such common components. An aperture formed in the elongate support member 28 receives a rim defined on a first flange 102 from the side of the elongate support member facing away from the seat. A second flange 104 is received coaxially with the first flange 102 on the same side of the elongate support member as the seat. An axle 106 is fixed against rotation to the inside of the second flange 104 such that it extends through the aperture formed in the elongate support member and the first flange 102. The third pulley arrangement 86 comprises a first toothed hand support pulley 108 which engages with the second toothed drive belt 88. The first toothed hand support pulley 108 is fixed to the proximal end of the base portion 44. The axle 106 extends through an aperture in the centre of the first toothed hand support pulley 108 whereby the first toothed hand support pulley 108 rotates about the axle 106 to move the base portion 44. The base portion 44 comprises a main housing 110 and a cover 112. The main housing 110 defines a space which is enclosed by way of the cover 112. A second toothed hand support pulley 114, a hand support drive belt 116 and a third toothed hand support pulley 118 are received in the space defined by the main housing 110. The axle 106 extends into the space defined by the main housing 110 by way of an aperture formed in the proximal end of the base portion 44. The axle 106 extends through an aperture formed in the centre of the second toothed hand support pulley 114. The second toothed hand support pulley 114 defines a keyway and the axle 106 defines a key which engages with the keyway whereby relative rotation of the second toothed hand support pulley 114 and the axle 106 is prevented. The second toothed hand support pulley 114 therefore rotates within the main housing 110 as the base portion 44 rotates. A proximal end of the hand grippable portion 38 is received through an aperture formed in the distal end of the base portion 44 such that it extends through an aperture formed in the centre of the third toothed hand support pulley 118. The third toothed hand support pulley 118 defines a keyway and the proximal end of the hand grippable portion 38 defines a key which engages with the keyway whereby relative rotation of the third toothed hand support pulley 118 and the hand grippable portion 38 is prevented. Rotation of the second toothed hand support pulley 114 within the main housing 110 as the base portion 44 rotates is transmitted to the third toothed hand support pulley 118 by way of the hand support drive belt 116 which engages with the second and third toothed hand support pulleys 114, 118 by way of cooperating toothed profiles. Rotation of the base portion 44 by way of the first toothed hand support pulley 108 therefore causes rotation of the second toothed hand support pulley 114 which in turn causes rotation of the third toothed hand support pulley 118 whereby the hand grippable portion 38 is rotated. Rotation of the hand grippable portion 38 in this fashion orientates the operable controls 42 properly as the distal end of the base portion 44 is moved through an arc.
An exploded perspective view of components of the drive arrangement of Figure 5 operable to move the seat of the stairlift apparatus is shown in Figure 7. Components of the view shown in Figure 7 in common with the views shown in Figures 1 to 5 are designated with like reference numerals. The reader's attention is directed to the description provided above with reference to Figures 1 to 5 in respect of such common components. A seat axle 130 is attached fixedly at a proximal end to a bracket 131 which is coupled fixedly to the elongate support member 28. The second pulley arrangement 82 comprises a first toothed seat pulley 132 and a housing 133. The housing 133 is generally tubular in shape and is received over the seat axle 130. A first housing bearing 134 is received in a recess defined in an end of the housing 133 and a second housing bearing 135 is received in a recess defined in an opposite end of the housing 133 to thereby provide for rotation of the housing 133 around the seat axle 130. A seat bearing housing 136 is of generally annular form and defines a recess at each end with each of first and second seat bearings 137, 138 being received in a respective recess. The seat bearing housing 136 and first and second seat bearings 137, 138 are received over the housing 133 for rotation thereon by way of the first and second seat bearings 137, 138, with each comprising a ball race on the outside surface and a ball race on the inside surface. An end of the housing 133 oriented away from the bracket 131 defines a flange which is attached fixedly to a face of the seat support arm 32 oriented towards the bracket 131. The seat bearing housing 136 and first and second seat bearings 137, 138 are received over the housing 133 such that the flange is beyond the seat bearing housing 136 and first and second seat bearings 137, 138. The elongate support member 28 defines an aperture through which the seat axle 130 passes and such that the seat bearing housing 136 is fixed to the elongate support member, such as by way of bolts, on the side of the elongate support member oriented towards the bracket 131 and the seat support arm 32 is on the opposite side of the elongate support member oriented away from the bracket 131.
The seat support arm 32 defines an enclosed space. The side of the seat support arm 32 oriented towards the bracket 131 and adjacent the elongate support member 28 defines an aperture through which the distal end of the seat axle 130 passes. The distal end of the seat axle 130 also passes through a second toothed seat pulley 139 mounted for rotation within the space defined by the seat support arm 32. A key is defined towards the distal end of the seat axle 130 and the inside surface of the second toothed seat pulley 139 defines a keyway, with the key and keyway being configured for releasable engagement whereby relative rotation of the second toothed seat pulley 139 and the seat axle 130 is prevented. The seat axle 130 defines a flange at the distal end thereof whereby the previously described components are held on the seat axle. The key is disposed towards the distal end of the seat axle 130 such that the distal end of the seat axle 130 is adjacent the inside surface of the side of the seat support arm 32 further away from the bracket 131. The inside surface of the side of the seat support arm 32 defines a circular recess in which a seat bearing 140 is received, with the seat axle 130 passing through the seat bearing 140. This configuration provides for rotation of the seat support arm 32 around the seat axle 130.
The first toothed seat pulley 132 has teeth on its external surface and engages with cooperating teeth on the first toothed drive belt 84. The housing 133 is received in part at an end opposite the flange in an aperture formed in the centre of the first toothed seat pulley 132. A protrusion 142 extends from the surface of the part of the housing 133 received in the aperture of the first toothed seat pulley 132. The surface of the aperture of the first toothed seat pulley 132 defines a circumferentially extending recess 144. The first toothed seat pulley 132 and the housing 133 are configured such that the protrusion 142 is received in the recess 144 whereby the protrusion moves circumferentially in the recess as the first toothed seat pulley 132 rotates when driven by the drive motor 46. When the protrusion 142 abuts against the end of the recess 144 the housing 133 is then rotated by the first toothed seat pulley 132. Rotation of the housing 133 about the seat axle 130 therefore causes rotation of the seat support arm 32 about the seat axle 130 in view of the flange of the housing 133 being fixedly attached to the outside of the seat support arm. Rotation of the seat support arm 32 about the seat axle 130 causes the back of the seat to rise up or drop down. As a consequence of cooperation of the protrusion 142 and the recess 144, the seat support arm 32 rotates through a predetermined number of degrees less than the first toothed seat pulley 132 whereby the back of the seat rotates through a predetermined number of degrees less than the hand support. The length of the recess 144 determines the predetermined number of degrees. Typically the predetermined number of degrees is in the range of 20 to 30 degrees. As mentioned above, configuring the force transmitting arrangement in this fashion reduces the likelihood of a person being crushed between the seat and the hand support.
Considering Figure 7 further, a third toothed seat pulley 148 is mounted for rotation within the space defined by the seat support arm 32 towards the distal end of the seat support arm. A toothed seat drive belt 150 is fitted over and therefore mechanically engages with the outside of each of the second toothed seat pulley 139 and the third toothed seat pulley 148. A joint arrangement 152 is mounted towards the distal end of the seat support arm 32. The joint arrangement 152 comprises a first joint component 154 and a second joint component 156. Adjacent ends of the first and second joint components 154, 156 form a hinged joint which provides for rotation about a vertically extending axis. The other end of the second joint component 156 is attached to the second portion 26 of the seat where the first and the second portions 24, 26 join. The seat can be rotated thereby to the stored disposition shown in Figure 4. The other end of the first joint component 154 defines a shaft bearing a key with a joint arrangement bearing 158 being received over the shaft. The side of the seat support arm 32 defines an aperture which is coaxial with an aperture through the third toothed seat pulley 148. A keyway is defined in the inside surface of the third toothed seat pulley 148. The shaft of the first joint component 154 passes through the aperture in the seat support arm 32 and into the aperture through the third toothed seat pulley 148 such that the key and keyway cooperate to resist relative rotation of the third toothed seat pulley 148 and the shaft. The distal end of the shaft defines a flange whereby the previously described components are held on the shaft. The joint arrangement bearing 158 is received in a recess formed in the side of the seat support arm 32 around the aperture through which the shaft passes. As described above, rotation of the seat support arm 32 around the seat axle 130 causes the back of the seat to rise up or drop down relative to the front of the seat. As the seat support arm 32 rotates around the seat axle 130, inter-engagement of the second toothed seat pulley 139 with the seat axle causes movement of the toothed seat drive belt 150 around the second toothed seat pulley 139 which in turn rotates the third toothed seat pulley 148. In view of the third toothed seat pulley 148 inter-engaging with the shaft of the first joint component 154, the shaft rotates on the joint arrangement bearing 158 with the third toothed seat pulley 148 relative to the seat support arm 32. Rotation of the shaft of the first joint component 154 causes rotation of the second portion 26 of the seat whereby the second portion 26 of the seat is maintained substantially vertical despite a change in orientation of the first portion 24 of the seat as the seat support arm 32 rotates about the seat axle 130 such that the back of the seat rises up or drops down.

Claims

Stairlift apparatus (12) comprising:
a chassis (18) which is configured to be mechanically coupled to a rail (14) mounted on a stairway for movement of the chassis along the rail;

a seat (20) mounted on the chassis, the seat being configured to support a person when the stairlift apparatus is in use, the seat facing the direction of travel during use of the stairlift apparatus, the seat comprising a first portion (24) on which the person sits or perches and a second portion (26) which provides support for the back of the person;

a hand support (22) mounted on the chassis, the hand support having a hand grippable portion (38), the stairlift apparatus being configured such that during use a person is one of carried up or down stairs when supported by the seat and aided by gripping the hand support when walking up or down stairs;

a drive arrangement comprising a drive motor (46) mounted on the chassis and a force transmitting arrangement operable to transmit force from the drive motor; and

a seat support arm (32) mechanically coupled to the seat and to the chassis to thereby support the seat on the chassis, characterised in that:
the force transmitting arrangement comprises a second rotating element (82), a seat rotating element (148) and a seat drive belt (150), the second rotating element being mounted on the seat support arm at a first location, the seat rotating element being mounted on the seat support arm at a second location, the first and second locations being spaced apart along the seat support arm, the seat drive belt being disposed to transmit rotation of the second rotating element to the seat rotating element;

the seat support arm is mechanically coupled at the first location to the chassis for rotation in relation to the chassis by way of the second rotating element and is mechanically coupled at the second location to the seat for rotation of the seat support arm and the seat in relation to each other by way of the seat rotating element; and

adjacent edges of the first and second portions are mechanically coupled for rotation of the first and second portions in relation to each other, the seat rotating element being mechanically coupled to the seat to provide for rotation of the first portion in relation to the second portion by operation of the force transmitting arrangement.
The stairlift apparatus according to claim 1 configured such that the stairlift apparatus is changeable between a first disposition in which a person is carried up or down stairs when supported by the seat and a second disposition in which a person is aided up or down stairs by gripping the hand support when on foot, at least one of the seat and the hand support being changeable between the first and second dispositions.
The stairlift apparatus according to claim 1 or 2 in which the force transmitting arrangement further comprises a first rotating element (80) and a drive belt (84), the first rotating element being mounted on the drive motor and the drive belt being disposed to transmit rotation of the first rotating element to the second rotating element.
The stairlift apparatus according to any one of the preceding claims in which the first location is towards a proximal end of the seat support arm and the second location is towards a distal end of the seat support arm.
The stairlift apparatus according to any one of the preceding claims in which the drive arrangement is operable to change the seat between first and second seat dispositions, the seat facing in a first direction in the first seat disposition and the seat facing in a second, opposite direction in the second seat disposition.
The stairlift apparatus according to claim 5 configured such that the drive arrangement is operable without user control to change from the first to the second seat disposition when the stairlift apparatus reaches the top of the stairway and to change from the second to the first seat disposition when the stairlift apparatus reaches the bottom of the stairway.
The stairlift apparatus according to any one of the preceding claims in which the hand support comprises a base portion (44) from which the hand grippable portion extends, the base portion being mounted for rotation in relation to the chassis and the force transmitting arrangement further comprises a first rotating element (80), a hand support rotating element (86) mounted on the hand support and a hand support drive belt (88), the first rotating element being mounted on the drive motor and the hand support drive belt being disposed to transmit rotation of the first rotating element to the hand support rotating element, the hand support being rotated by way of the hand support rotating element.
The stairlift apparatus according to any one of the preceding claims in which the seat is configured such that the first and second portions are rotatable such that they are overlying, the stairlift apparatus being configured such that the seat is rotatable about a vertically extending axis to thereby reduce space occupied by the stairlift apparatus when the first and second portions are overlying.
The stairlift apparatus according to any one of the preceding claims in which the hand support is mounted for rotation in relation to the chassis between a first disposition in which a person is carried up or down stairs when supported by the seat and a second disposition in which a person is aided up or down stairs by gripping the grippable portion of the hand support when on foot.
The stairlift apparatus according to claim 9 in which the hand support is configured such that the hand grippable portion describes an arc between the first and second dispositions.
The stairlift apparatus according to any one of the preceding claims configured for change between a first disposition in which a person is carried up or down stairs when supported by the seat, a second disposition in which a person is aided up or down stairs by gripping the hand support when on foot, and a third disposition in which a person perches on the seat.
The stairlift apparatus according to claim 11 in which the seat is higher in the third disposition than in the first disposition and a first portion of the seat on which the person sits or perches is at an incline in the third disposition and substantially level in the first disposition.
The stairlift apparatus according to claim 11 or 12 in which the hand support is higher when in the third disposition than when in the first disposition.
A stairlift arrangement comprising: a rail configured to be mounted on a stairway such that the rail extends up a stair; and stairlift apparatus according to any one of the preceding claims which is configured to be mechanically coupled to the rail for movement along the rail.