GB2621860A

GB2621860A - Improvements in or relating to stairlifts

Info

Publication number: GB2621860A
Application number: GB2212330.1A
Authority: GB
Inventors: Daniel Woodhams Max
Original assignee: Stannah Stairlifts Ltd
Current assignee: Stannah Stairlifts Ltd
Priority date: 2022-08-24
Filing date: 2022-08-24
Publication date: 2024-02-28
Also published as: GB202212330D0

Abstract

A stairlift rail 13 has an upper end 15 and a lower end and drive and reaction surfaces 17, 18. Adjacent to the upper end of the rail the drive surface 24 is vertical whilst a distal part 26 of the reaction surface projects away from a reference plane (RP fig.5), possibly in a helical manner. When a stairlift is driven on the vertically aligned upper end of the rail, possibly using friction rollers, the reaction roller effects rotation of a carriage about a vertical axis, possibly around the axis of the drive member.

Description

IMPROVEMENTS IN OR RELATING TO STAIRLIFTS

Field of the Invention

This invention relates to stairlifts and, more particularly to a stairlift which includes a facility to swivel a stairlift chair at an end of the stairlift rail, thereby making it easier for a passenger to enter and/or exit the chair.

Background to the Invention

A stairlift is a well-known form of apparatus mounted in a staircase which serves to transport physically impaired persons between the floors of a building. A rail is mounted on the staircase to extend along an edge of the staircase. A stairlift carriage containing drive, support and reaction rollers is mounted on the rail for movement there-along and a chair is, in turn, mounted on the carriage. Typically a stairlift is configured so that, when the carriage is moving along the rail, a passenger seated in the chair faces perpendicularly to the direction of travel as this is deemed the safest mode of operation. To enable the passenger to safely enter and leave the chair at an end of a journey, particularly at the top of the rail, the chair is preferably swivelled relative to the carriage so that the chair is facing in an uphill direction. The swivel mechanism may be manual or powered but, if powered, a separate, additional, motor and associated motor control must be provided. This adds cost and a degree of complexity to a stairlift installation.

It is an object of the present invention to provide a swivelling facility for a stairlift and/or a stairlift including a swivelling facility which will address the aforementioned problem or which will at least provide a novel and useful alternative.

Summary of the Invention

In a first aspect the invention provides a stairlift rail having an upper end and a lower end; drive and reaction surfaces extending between said upper end and said lower end, said drive and reaction surfaces being substantially parallel, a reference plane extending between said drive and reaction surfaces wherein adjacent to the upper end of said rail said drive surface is aligned substantially vertically and wherein a distal end part of an upper section of said reaction surface projects away from said reference plane.

Preferably said drive arid reaction surfaces are defined by or on two spaced tubular members.

Preferably said tubular members are round when viewed in cross-section.

Preferably said drive surface is a friction drive surface.

Preferably said reference plane is substantially vertical.

Preferably the distal end part of the upper section of the reaction surface comprises a helical section of tubular rail.

In a second aspect the invention provides a stairlift comprising a stairlift rail as set forth above; a carriage having drive and support rollers configured to engage the drive surface, and at least one reaction roller configured to engage the reaction surface; a chair mounted on said carriage; and a levelling facility configured and operable to maintain the chair level as said carriage moves along said rail, the construction and arrangement being such that when the drive and reaction rollers are driven on the substantially vertically aligned section of drive surface, engagement of the at least one reaction roller with the distal end part of the reaction surface effects rotation of the carriage about a substantially vertical axis.

Preferably the drive and reaction surfaces are defined by or on tubular members, and wherein the construction and arrangement is such that engagement of the reaction roller with the distal end part of the tubular reaction member causes the carriage to rotate about the axis of the tubular drive member.

Preferably said drive and support rollers are configured to frictionally engage said drive surface.

Many variations in the way the present invention can be performed will present themselves to those skilled in the art. The description which follows is intended as an illustration only of one means of performing the invention and the lack of description of variants or equivalents should not be regarded as limiting Subject to the scope of the appended claims, wherever possible, a description of a specific element should be deemed to include any and all equivalents thereof whether in existence now or in the future.

Brief Description of the Drawings

An embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1: shows an isometric view, looking down from the front; of a stairlift carriage including a stairlift rail according to the invention, the carriage being positioned below the upper end of the rail; Figure 2: shows a view from the rear of the carriage and rail shown in Figure 1; Figure 3: shows a view similar to Figure 1 but with the carriage positioned up the upper end of the rail; Figure 4: shows a view from the rear of the carriage and rail shown in Figure 3; and Figure 5: shows a cross-sectional view of the rail, viewed along the directional axis of the rail

Description of Working Embodiment

The drawings show a stairlift installation 10 mounted on a staircase 11 which terminates at its upper end at floor level 12. The installation 10 includes a rail 13 and a carriage 14 mounted on the rail for travel between an upper end 15 of the rail, and a lower end (not shown). The installation will further include a chair mounted on the carriage via a chair interface, which pivotally engages the carriage at pivot point 16, and those skilled in the art will also appreciate that a levelling facility will be provided which operates to provide relative pivotal movement about pivot point to ensure the chair is maintained level as the carriage moves through transition bends in the rail. For reasons of clarity, and because they form no part of this invention the chair, the chair interface and the levelling facility are not shown in the drawings.

In the conventional manner, the rail comprises a drive surface 17 and a reaction surface 18 such that the carriage is principally supported on, and displaced along, the drive surface by support and drive rollers 19 whilst the reaction rollers 20 anchor the drive and support rollers 19 to the drive surface 17 and prevent the carriage 14 from rotating about the axis of the support surface. As will become apparent from the description that follows, in this invention the reaction rollers 20 provide a steering function.

By way of example only, the carriage and roller configuration may take the form described in our published International Patent Application W02022/003332 Again in keeping with convention the drive and reaction surfaces extend along the rail in a substantially parallel manner and, in this particular example, are defined respectively by or on spaced tubular members 21 & 22. Tubular members are a well-known and convenient basis for stairlift rail fabrication, but the invention may be applied to other rail configurations. Using the tubular members shown, the upper tube 21 which provides the drive surface 17 is for the most part of the rail length positioned vertically above the lower rail 22 that provides the reaction surface 18 and, for the purposes of this description, a reference plane RP, shown in Figure 5, extends substantially vertically between the tubular members when viewed along the directional axis of the rail.

A particular feature of this invention is that the upper end 15 of the rail is provided with a positive transition bend 23 as the rail, when viewed from above in plan, nears the floor level 12. The transition is configured so that the two tubular members 21 & 22 are brought into a vertical state, the upper end part 24 of the drive surface remaining vertical whilst the reaction surface remains vertical for a distance sufficient for the carriage plane 25 to assume a substantially horizontal state, the distal end part 26 of the tubular member 22 then being directed out of the reference plane and, in this case, to the rear of the reference plane. This is preferably achieved by providing the distal end part 26 of the reaction surface in the form of a helical, that is to say a section of rail that curves in both a horizontal and a vertical plane.

The effect of this configuration is that, as the carriage 14 is driven up the vertical end section 24 of drive surface, the reaction rollers 20 are driven on to the distal end part 26 of reaction surface 18 which causes the carriage 14 to rotate about the axis of drive end section 24. It thus follows that a chair mounted on the carriage via pivot 16 will be rotated from the position shown in Figure 1 in which the chair is aligned substantially perpendicular to the direction of travel, to the position shown in Figure 3 in which the chair is facing in an uphill direction thus making it easier for a passenger to enter and exit from the chair.

In the example herein described the invention is applied to a stairlift in which the carriage is driven along the rail by application of friction however it is not beyond comprehension that the invention could be applied to a stairlift driven by inter-engaging drive components.

This embodiment of the invention has been described as being applied to the upper end of the stairlift rail but those skilled in the art will appreciate that the same principle could be applied to achieve a swivelling action at the lower end of the rail

Claims

Claims A stairlift rail having an upper end and a lower end; drive and reaction surfaces extending between said upper end and said lower end, said drive and reaction surfaces being substantially parallel, a reference plane extending between said drive and reaction surfaces wherein adjacent to the upper end of said rail said drive surface is aligned substantially vertically and wherein a distal end part of an upper section of said reaction surface projects away from said reference plane.A stairlift rail as claimed in claim 1 wherein said drive and reaction surfaces are defined by or on two spaced tubular members A stairlift rail as claimed in claim 2 wherein said tubular members are round when viewed in cross-section.A stairlift rail as claimed in any one of the preceding claims wherein said drive surface is a friction drive surface.A stairlift rail as claimed in any one of the preceding claims wherein said reference plane is substantially vertical.A stairlift rail as claimed in any one of the preceding claims wherein the distal end part of the upper section of the reaction surface comprises a helical section of tubular rail A stairlift comprising a stairlift rail as set forth above; a carriage having drive and support rollers configured to engage the drive surface, and at least one reaction roller configured to engage the reaction surface; a chair mounted on said carriage; and a levelling facility configured and operable to maintain the chair level as said carriage moves along said rail, the construction and arrangement being such that when the drive and reaction rollers are driven on the substantially vertically aligned section of drive surface, engagement of the at least one reaction roller with the distal end part of the reaction surface effects rotation of the carriage about a substantially vertical axis.A stairlift as claimed in claim 7 wherein the drive and reaction surfaces are defined by or on tubular members, and wherein the construction and arrangement is such that engagement of the reaction roller with the distal end part of the tubular reaction member causes the carriage to rotate about the axis of the tubular drive member.A stairlift as claimed in claim 7 or claim 8 wherein said drive and support rollers are configured to frictionally engage said drive surface.