GB2483799A - Stairlift with separate handle or suspended seat - Google Patents

Abstract

Two stairlifts are disclosed. The first 10 includes two carriages 13, 14 mounted for independent movement up and down respective rails 11, 12 by means of a motorised winch 16, 17 winding onto at least one drum 15 first and second flexible members 18, 19 connected to the carriages 13, 14, with a folding handle 22 mounted to one of the carriages 14, and a folding seat or platform 23 to the other of the carriages 13. The upper rail 12 may be used as a handrail. The second stairlift includes a rail (11 fig 2) with curved portions, a plurality of carriages 13 resiliently connected to form an articulated train movable along the rail, a drive mechanism to drive the carriages 13 along the rail and a suspension structure 48, 49 connecting the carriages 13 to a pivoting suspension member (50 fig. 4) upon which is supported a seat 123. The resilient connection between the carriages may be a helical spring (52 fig. 5) received in an aperture in each carriage 13. The suspension structure may include two elongate members 48, 49 pivotally connected to one another at one end and pivotally connected to respective carriages 13 at the other end.

Description

STAIRLIFT

Technical field

The present invention relates to stairlifts or inclined elevator apparatus for conveying S or assisting persons up and down flights of stairs.

Background of the Invention

Stairlifts, typically comprise a carriage mounted on an inclined rail for movement along the rail. The carriage may include a seat for carrying the user, a drive motor and gearbox and some form of drive mechanism, such as a rack and pinion, a friction drive, or a winch that winds or unwinds a cable anchored at the top of the stairway. A drawback of these arrangements is that the carriage assembly is heavy, and unless a costly and difficult to install counterweight system is used, the operation of such stairlifts is relatively energy inefficient.

For a user's safety and peace of mind when being conveyed it is desirable for the user to be seated securely, and some prior art designs provide a seat-belt for this purpose. While a suitably placed hand grip provides a high level of security, the hand grips fixed to a seat on prior art stairlifts provided a travelling assembly that takes up considerable space and such stairlifts are poorly suited to being installed in a narrow stairway.

Whereas some users may require to be conveyed in a sitting position on such stairlifts, others who prefer to maintain a greater degree of mobility are better served by some other form of stair-climbing assistance. It will be understood, therefore, that there is a need for a stairlift which is less obtrusive, taking up less space in the stairway, but which is also readily adaptable to the differing needs of users, and which is relatively cost-efficient to produce and operate.

It is an object of the present invention to overcome or substantially ameliorate the above disadvantages or more generally to provide an improved stairlift.

Disclosure of the Invention

According to one aspect of the present invention there is provided a stairlift including: first and second rails; first and second carriages mounted on the first and second rails respectively, for movement along the rails; a handle and a user-carrying member mountable to the first and second carriage respectively; first and second flexible members; a rotary motor; and at least one drum driven by the motor for winding up the flexible members to thereby drive the first and second carriages along the rails.

The user-carrying member is preferably a seat, but may comprise a platform (e.g. for carrying a wheelchair), or the like.

Optionally, the at least one drum may include first and second drums driven by the motor and upon which the first and second flexible members are wound respectively.

Preferably the rails have respective upper ends and lower ends, the at least one drum is mounted proximate the upper ends, and the first and second flexible members extend between the at least one drum and the first and second carriages respectively.

Preferably each carriage includes at least two rollers for supporting the carriage on the respective rail.

The flexible members may comprise a cable, wire, chain, rope, belt, webbing, or the like. Preferably the first and second rails are substantially parallel. The first and second stairlift rails may be linear, or curved. If curved, the rails may be curved in either a vertical plane or in a horizontal plane, or simultaneously in both horizontal and vertical planes.

The first and second stairlift rails are preferably hollow, with the carriages received within the rails. Preferably the first rail is disposed below the second rail, and a space extends above the second rail such that the second rail can be used as a handrail.

In another aspect, the invention provides a stairlift including: a rail including curved portions; a plurality carriages mounted on the rail, adjacent carriages being connected in a train for relative articulation during movement along the rail; suspension structure connecting the carriages to a pivoting suspension member; a seat supported on the suspension member; a motor; and a drive mechanism connected to the motor to drive the carriages along the rails.

Preferably a resilient coupling connects the adjacent carriages. Preferably the resilient coupling comprises an elastic member fixed between adjacent carriages.

Most preferably the elastic member comprises a helical spring having a longitudinal axis, the helical spring being received in an aperture in each of the carriages.

Preferably the suspension structure comprises two elongate structural members connected together at one end by a flexible joint, and pivotally connected at their opposing ends to respective ones of the carriages. Preferably the flexible joint comprises a spherical bearing.

Preferably the suspension structure further comprises an axle rigidly connected to one of the two elongate structural members, and wherein the pivoting suspension member is mounted to pivot upon the axle.

Preferably the carriages are supported upon rollers. Optionally, the carriages may be supported upon low friction sliders.

This invention provides a stairlift which is effective and efficient in operational use, which reduces maintenance costs, and which by its modular construction and versatile to the operation. The device may be economically constructed and has an overall simple design which minimizes manufacturing costs. It is advantageously able both to convey users in a sitting position as well as provide stair-climbing assistance. In particular it provides a compact and unobtrusive stairlift, which may be particularly advantageous in smaller homes and offices, for instance.

Brief Descripqn_qf the Drawinqs Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: Figure 1 is a schematic perspective view showing the main functional components of a stairlift according to a first embodiment of the invention; Figure 2 is a schematic side view of a stairlift according to a second embodiment of the invention; Figures 3 and 4 are side and front views respectively of a first carriage assembly of the stairlift of Fig. 2; Figures 5 and 6 are side and front views respectively of a train of carriages of the carriage assembly of Figs. 3 and 4, and Figure 7 is a fragmentary top view of the connection between the upper ends of the structural members of the carriage assembly of Figs. 3 and 4.

Descrjption of the Preferred Embodiments Referring firstly to Fig. 1, according to the invention a stairlift 10 is provided, including first and second rails 11, 12 and first and second carriages 13, 14. The stair lift includes a novel drive mechanism, including a winch drum 15 rotated by a motor 16 driven through a gearbox and brake assembly 17. The first and second cables 16, 19 are wound onto, and unwound from the drum 15 to thereby drive the first and second carriages 13, 14 along the rails 11, 12 at the same speed.

The rails 11, 12 may be linear as shown schematically in Fig. 1, or curved (as described below with reference to Fig. 2) to follow the general path of the stairs 21.

In either case the rails are parallel, and disposed one above the other along one edge of a stairway 20. For instance, the rails 11, 12 may be mounted to protrude from an upright wall bounding the stairway 20, or they may be recessed into the wall.

The first rail may be lowermost, positioned at the height of a skirting board (into which it may be integrated). The second rail 12 may be uppermost and is conveniently positioned at handrail height (at a height between 800 and 950mm).

The precise form of the rails is not an essential feature of the invention but they may, as shown, be substantiafly of channel-shaped form.

A seat 23 may be mounted to the first carriage 13, either fixedly or detachably. The seat 23 projects into the stairway, and is suspended, via the carriage 13, upon the first rail 11 in a cantilevered manner. In the illustrated embodiment the seat 23 comprises a base 24 fixed to the carriage 13, and a seat back 25 connected to the base 24, and is of a folding type. The back 25 may be collapsed down onto the base 24, being connected to the base for pivoting about the axis 26. The seat collapsed in this manner may then be folded up out of the stairway 20, as the base 24 is connected to the carriage 13 for pivoting about axis 25. Although the seat is shown with the back 24 at the trailing edge of the seat, it may be arranged generally along the leading edge or the inner, lateral edge -such that a user faces down the stairway or across the stairway when seated.

A handle 22 is connected to the carriage 14. The handle 22 may include an elongate hollow structural member, to which one or more grips 28 are fixed. Like the seat, the handle 22 may be mounted to fold away out of the stairway, as by a pivot connecting the handle 22 to the carriage 14 for rotation about axis 29.

The carriages 13, 14 may be supported upon rollers 30, which extend from the upper side of the carriages, as well as from the lower side of the carriages. The carriages are slidingly received within the hollow rails 11, 12. The rails 11, 12 may have the open mouth 32 facing toward the stairway, and receiving the part connecting the carriage and handle, or the carriage and seat 23. The mouth 32 may be bounded by re-entrant lips 33, 34 such that the carriages are substantially enclosed within the rails 11, 12.

The drive system for the stairlift, including the winch drum 15, motor 16 and gearbox 17, is mounted adjacent the upper ends of the rails 11, 12. In a domestic application, this drive system may be mounted in a recess in the wall in the form shown herein. However, the drive mechanism may also be mounted within the carriage.

The stairlift of Fig. 1 can advantageously be used in a number of ways, according to user preferences or requirements. When not in use the seat 23 is either detached from the carriage 13, or else is collapsed as described above, to lie generally against a side of the stairway. Likewise the handle 22 may be detached or pivoted from a generally horizontal in-use position to an upright stored position.

It will be appreciated that, as the motor is powered to rotate the drum assembly 15 in an clockwise direction as shown in the drawings, the cables 18, 19 are wound onto the drum and the carriages 13, 14 are drawn up the rail 11, 12 together. When the motor is rotated in the opposite direction, both carriages 13, 14 are allowed to move down the rail under gravity as the cables 18, 19 unwind from the drum.

An over-speed governor (not shown) may be provided in the drum assembly 15 to brake the drum to a halt in the event the speed of rotation of the drum exceeds a pre-determined maximum speed. Further, each of the cables 18, 19 may be led over monitoring means in the form of tension sensors mounted within the carriages. The tension sensors, which may be electrical or mechanical in form, are configured and arranged to sense loss of tension in either web, such as would occur in the event of fracture or detachment of the web, or failure in the drive system. In the event of loss of tension in one cable, the main electrical control within the stair lift would be triggered to cause the carriage to move slowly to the bottom of the rail, and thereafter prevent further use of the stairlift until the web was repaired.

In a first mode, the seat is configured with the base generally horizontal as shown, the user sits upon the seat 23 facing up the stairway and is able to grasp the handle 22 extending directly in front of the user. When seated in this manner, the handle is pivoted down and latched in its lower, closed position. The user is thus made quite secure -even without a restraint on the outer side of the chair or handle -and there is no need for a safety belt. For even further security, the handle and/or seat may be configured such that they do cooperate to also restrain laterally outward movement of user, when pivoted down for use. The drive mechanism is then operated, as by a wireless remote control mounted on the handle, releasing the brake and operating the motor to simultaneously raise or lower the carriages 13, 14 and the attached seat 23 and the handle 22.

In a second mode, the device may be used to provide stair-climbing assistance.

With the seat 23 maintained in its non-use position, the user folds down and grasps the handle 22, before operating the drive mechanism. In this manner, by connecting the handle 22 and seat 23 only by means of the cables 18, 19 two separate modes of operation can be obtained from the stairlift, while advantageously avoiding, for instance, structural members extending between the seat and handle. The invention thereby provides a stairlift which is less obtrusive, takes up less space in the stairway. Moreover, with the lower rail 12 hidden in a skirting and the upper fail 13 also able to be used as a conventional handrail the stairlift offers improved aesthetics.

A second embodiment of the stairlift is shown in Figs 2-7, and like numbers are used to refer to like components of this second embodiment. This exemplary stairlift ascends a more complex stairway with three flights of stairs separated by two landings 40 and 41, maintaining substantially the same elevation from the adjacent floor level throughout is path. The first and second rails 11, 12 are parallel, and include linear sections along each flight of stairs and along the landing 40. The rails follow a path having curved portions providing smooth transitions in their direction, specifically with slope transitions providing a curve in a vertical plane between the first flight 42 and the landing 40, and between the landing 40 and the second flight 43. Around the corner spanning between the second and third flights 43, 44 a further curve is provided in a horizontal plane.

The motorized drive mechanism may be as described above with reference to the first embodiment, mounted in a housing 46 at the top of the stairway. If another type of drive is employed, then separate motors and drives may be provided for moving the carriage 13 to which the seat 123 is mounted, and for moving the carriage 14 mounting the handle 23, allowing these two parts to move independently of one another.

To accommodate the slope transitions within the plane in which the rails 11, 12 lie, the seat 123 is suspended to swing about a horizontal axis located above the seat, as described in further detail with reference to Figs 3 and 4 below. In an alternative embodiment, the seat may pivot about a lower horizontal axis, below the combined centre of gravity of the seat and user and a tilt control mechanism may be used to control the angle of the seat relative to the rails, such that, for instance the user is not pitched forward at the transition from the first flight 42 to the landing 40. The tilt control mechanism may be operated by a carriage (not shown) running in a control rail 45 (shown in dashed outline in Fig. 2) disposed between the rails 11 and 12. As the spacing between the control rail 45 and the rail 11 varies generally over the landing, the seat is tilted relative to the rail.

Referring to Figs 3 to 7, the first carriage assembly 100 includes a seat 123 carried on a train of carriages 13 which run inside the rail 11. Suspension structure, which may include first and second elongate structural members 48, 49, connects the carriages 13 to a pivoting suspension member 50, below which the seat 123 is suspended, such that it is generally free to swing. The second carriage assembly (not shown) may be of like construction to that of the first embodiment.

Each of the carriages 13 may include a chassis 53 supported upon rollers 30 extending from the lower sides of the chassis 53. Additional rollers 30 pivot upon parallel axes and extend from the upper side of the carriages 13, and rollers 47 extend laterally from both sides of the carriages. In the known manner, these rollers are positioned and arranged to ensure the carriage is firmly supported on the rail, yet can roll freely along within the hollow rails 11, 12. The precise roller arrangement does not form part of this invention. The carriages 13 are connected in a train for relative articulation during movement along the rail by one or more couplings 52. A helical spring coupling 52 may connect two or more carriages, and in the illustrated embodiment a single helical spring coupling 52 connects three carriages, passing lengthwise through the middle carriage of the train.

The lower ends of the structural members 48, 49 are connected to the carriages 13 by pivots 54, extending generally horizontally, parallel to the axes of the rollers 30.

Likewise an axle 55 fixed to one of the structural members 48, 49 supports the suspension member 50 to pivot about a generally horizontal axis in use. As shown in Fig. 7, the upper end of the member 49 may be rigidly fixed to the axle 55. The members 48 and 49 are mutually connected at their upper ends by a flexible joint, such as a spherical bearing 56. This flexible joint provides the relative movement needed for the train of carriages 13 to traverse the curved portions of the rails.

The suspension member 50 may be located centrally above the seat 123. The seat 123 may be fixed to the suspension member 50 by lines 58. In addition to connecting the carriages for movement relative to one another, a flexible coupling such as the spring coupling assists in distributing the loadings between the carriages, and makes for smoother, quieter performance. This arrangement provides the same advantages of use as the first embodiment.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.

Claims (7)

1. CLAIMS: 1. A stairlift including: a rail including curved portions; a plurality carriages mounted on the rail, adjacent carriages being connected in a train for relative articulation during movement along the rail; suspension structure connecting the carriages to a pivoting suspension member; a seat supported on the suspension member; a motor; and a drive mechanism connected to the motor to drive the carriages along the rails.a resilient coupling connects the adjacent carriages.the resilient coupling comprises an elastic member fixed between adjacent carriages.
2. 2. The stairlift of claim I wherein the elastic member comprises a helical spring having a longitudinal axis, the helical spring being received in an aperture in each of the carriages.
3. 3. The stairlift of claim I or claim 2 wherein the suspension structure comprises two elongate structural members connected together at one end by a flexible joint, and pivotally connected at their opposing ends to respective ones of the carriages.
4. 4. The stairlift of any one of claims 1 to 3 wherein the flexible joint comprises a spherical bearing.
5. 5. The stairlift of any one of claims I to 3 wherein the suspension structure further comprises an axle rigidly connected to one of the two elongate structural members, and wherein the pivoting suspension member is mounted to pivot upon the axle.
6. 6. The stairlift of any one of claims 1 to 3 wherein the carriages are supported upon rollers.
7. 7. A stairlift substantially as hereinbefore described with reference to and as shown in the accompanying drawings.