Patent Description:
wherein each motor is adapted to control the corresponding folding system according to a variable speed profile. The invention also relates to a method of controlling a stairlift.

A stairlift is a product which is typically meant for people with impaired mobility to provide support in travelling up and down a staircase whilst maintaining the functionality of the stairs for persons who are able to climb the stairs themselves. The stairlift is often installed in a person's home and typically comprises a drive unit that is arranged to drive a user carrier, e.g., a chair or a wheelchair platform, along a rail, mounted on or along one or more flights of a staircase.

<CIT> discloses a stairlift wherein the folding of the seat and/or, the chair leg and/or the footrest and/or the armrest is/are folded/unfolded automatically or manually. This is designed to save space about the stairlift installation.

<CIT> discloses a stairlift in which movement is regulated according to an entered velocity profile data. However this movement refers to the lift motor as such and not to a folding mechanism.

<CIT> discloses a folding chair having a seat base, a backrest and a pair of armrests, said chair further including a linkage connecting said seat base and said armrests, wherein the linkage is configured to regulate the displacement of said seat base between a substantially horizontal in-use position and a folded position in which the rear end is raised relative to the backrest.

The movements of folding component parts of a stairlift, e.g., a footrest; a chair seat; a chair leg, can also be accomplished by means of electro motors, wherein each electro motor is assigned to a specific component part(s). However, when the motors are switched on or off, the folding behavior is bulky, inelegant and inefficient.

It is thus an object of the invention, to improve the quality of folding and unfolding of component parts in a stairlift.

This object is solved by a stairlift according to claim <NUM> and a method according to claim <NUM> with further preferred embodiments detailed in the dependent claims and following description.

The invention refers to a stairlift having a curved or a straight rail, comprising.

This advantageously provides a stairlift that can be easily configured by folding and unfolding one or more movable part to welcome a travelling passenger, as well as enabling a stairlift to be quickly and efficiently stored once a passenger has reached their destination.

The term "folding" preferably refers to the movement of one body, e.g., a seat body, from a first position to a second position, wherein said positions are different. For example, folding can refer to the movement of the seat body from a forwards position (see. <FIG> for directional arrows) to an upwards position, wherein the forwards and upwards positions are not necessarily exactly perpendicular to each other.

The first motor is adapted to control a folding system comprised in the seat body and a folding system comprised in the leg body.

The second motor is adapted to control a folding system comprised in the footrest body.

According to an example, not covered by the invention, a third motor is adapted to control a third folding system comprised in the armrest body.

By providing each movable part of the stairlift with its own folding system, there are more options for customizing the folding and unfolding of the stairlift to suit customer wishes.

In an embodiment of the invention, each motor is adapted to implement at least:.

In an embodiment of the invention, the first speed profile and the third speed profile are variable speed profiles, wherein said variable speed profiles are not necessarily the same.

In an embodiment of the invention, the second speed profile is a constant or a variable speed profile.

By incorporating variable speeds and constant speeds, time can be saved when preparing the stairlift for use or for preparing it for storage. This advantageously increases passenger satisfaction.

The invention also refers to a method for controlling a stairlift as outlined above comprising the method steps of:.

Activation can optionally occur by pushing a button on an armrest, or a remote control device, or a control panel, which activates the first and/or second motor, e.g., the seat/leg folding motor and/or the footrest body motor and/or the armrest body motor. initiating the at least one motor according to:.

This advantageously provides a simple method for controlling the folding and unfolding of a stairlift, which improves usability and comfort for passengers.

In an embodiment of the invention, the first speed profile involves a speed acceleration.

In an embodiment of the invention, performing the method steps in the order b1 - b2 - b3 results in a folding operation or an unfolding operation.

The use of a third motor, adapted to control the armrest, is given for illustrative purposes only.

The invention is described in more detail with the help of the figures.

<FIG> show exemplary embodiments of a generic stairlift <NUM>, to which the invention can be applied. The stairlift <NUM> comprises a stairlift unit <NUM> which travels along a direction of travel D from a first landing area <NUM> to a second landing area <NUM>. The direction of travel D is defined by a rail <NUM> and is limited mainly by the course of an existing stairway <NUM> in a house. The stairlift unit <NUM> comprises a carrier <NUM>, which serves for guiding the stairlift unit <NUM> at the rail and which has a drive engine (not shown). Attached to the carrier is a chair/seat <NUM>. The carrier <NUM> has non-shown rollers, which roll along the rail <NUM>. For driving the carrier <NUM> positive engagements means (not shown) are provided on the rail <NUM>, which cooperates with driving means, in particular a driven pinion (not shown), of the stairlift unit <NUM>. This particular rail <NUM> has a curved shape, which deviates from a straight line; thus the direction of travel will change at least once during the course of the rail <NUM>. A leveling mechanism (not shown) is provided on the stairlift unit <NUM>, to keep the chair <NUM> always in a horizontal orientation, even if the inclination of the rail <NUM> varies during its course.

<FIG> shows the chair <NUM> wherein it comprises a base body <NUM>, which is attached to the carrier <NUM>. Attached to the base body <NUM> is a backrest body <NUM>, a seat body <NUM> and an armrest body <NUM>. The user sits on the seat body <NUM> during travel and rests their arms on the armrests <NUM>. Therefore the seat body <NUM> and armrest body <NUM> may be equipped with a suitable cushion.

The chair <NUM> also comprises a footrest body <NUM>, on which during travel a user can rest his feet on. For attaching the footrest body <NUM> at the rest of the chair <NUM> a leg body <NUM> is provided attaching the footrest body <NUM> with the seat body <NUM>.

<FIG> shows the respective folding axes S, F, L, A, relating to the component parts of the seat body <NUM>, the leg body <NUM> and the footrest body <NUM>. The seat body <NUM> is foldable along a seat axis S fixed to the base body <NUM> by a seat joint <NUM>. The seat joint <NUM> is located at a rearward section of the seat body <NUM>.

The leg body <NUM> is foldable along a leg axis L fixed to the seat body <NUM> by a leg joint <NUM>. The leg joint <NUM> is located at an upper section of the leg body <NUM> and at a forward section of the seat body <NUM>.

The footrest body <NUM> is foldable along a footrest axis F fixed to the leg body <NUM> by a footrest joint <NUM>. The footrest joint <NUM> is located at a lower section of the leg body <NUM> and at a rearward section of the footrest body <NUM>.

The armrest body <NUM> is foldable along a vertical axis A. Each of the foldable bodies shown <NUM>, <NUM>, <NUM>, <NUM> comprise a folding system <NUM> (not shown).

The terms rearward, forward, upward, downward are relative to a user's point of view when sitting on the unfolded chair <NUM>. The corresponding directions "rearward direction r", "forward direction f", "upward direction u" and "downward direction d" are shown in <FIG>. As can be seen with reference to the leg body <NUM> in particular, these directions indicate an approximate direction rather than an exact orthogonal direction.

<FIG> shows the chair <NUM> when in a folded (<FIG>) and unfolded (<FIG>) configuration.

<FIG> shows a schematic of the motor controls M1, M2 and their respective component parts <NUM>, <NUM>, <NUM> according to an embodiment of the invention. In <FIG>, the motor M1, when activated, controls the folding and unfolding of the seat body <NUM> and the leg body <NUM>, whilst the motor M2 when activated, controls the folding and unfolding of the footrest body <NUM>. As a first step, a first speed profile s1, s3 is initiated at one or both motors M1, M2. This speed profile will vary depending on whether a folding or unfolding operation is being carried out. If it is an unfolding operation, then the first speed profile is profile s1 and relates to a speed acceleration. The next speed profile implemented is profile s2, which relates to a constant speed, and finally the third speed profile implemented is profile s3, which relates to a speed deceleration. The motors M1, M2 can be activated at different times or at the same time. Optionally a folding system <NUM> can also be comprised in the armrest body <NUM> which is controlled by a motor M3. The motor M3 can be optionally coupled to the other motors M1, M2, however, the motor M3 shown here is not coupled to the motors M1 and M2, thus, the folding system of the armrest is independent of the folding systems comprised in the seat, leg and footrest bodies <NUM>, <NUM>, <NUM>.

The armrest body <NUM> can also be folded and unfolded manually - thus removing the need for the motor M3.

<FIG> shows a schematic of the motor controls M1, M2, M3 and their respective component parts <NUM>, <NUM>, <NUM>, <NUM> according to an embodiment of the invention. In <FIG>, the motor M1, when activated, controls the folding and unfolding of the seat body <NUM> and the leg body <NUM>; the motor M2 when activated, controls the folding and unfolding of the footrest body <NUM>; and the motor M3 when activated, controls the folding and unfolding off the armrest body <NUM>. As a first step, a first speed profile s1, s3 is initiated at one or all motors M1, M2, M3. This speed profile will vary depending on whether a folding or unfolding operation is being carried out. If it is an unfolding operation, then the first speed profile is profile s1 which relates to a speed acceleration. The next speed profile to be implemented is profile s2, which relates to a constant speed, and finally the third speed profile implemented is profile s3, which relates to a speed deceleration. The motors M1, M2, M3 can be activated at different times or at the same time.

<FIG> and <FIG> show a schematic top view representation of a folding system <NUM> according to an embodiment of the invention. The folding system <NUM> comprises both mechanical components and electronic components which together are designed to fold e.g., the leg body <NUM> with the seat body <NUM>. In the example shown in <FIG>, the folding system <NUM> is comprised in the seat body <NUM>. It should be noted that this is not to scale. The folding system <NUM> comprises a vane <NUM> movable along a spindle <NUM> and rod <NUM> system located between two fixing members <NUM>, a PCB <NUM> having a slot <NUM> through which the vane <NUM> can move. , and a plurality of opto-coupler pairs 103a-103d located at either side of the slot <NUM>. The opto-couplers 103a-103d emit and receive a signal <NUM> when not blocked and a signal <NUM> when blocked. In this particular example, the PCB <NUM> is connected at both top and bottom ends via wires.

In this particular example, the folding system <NUM> in the seat body <NUM> is coupled to a folding system <NUM> comprised in the leg body <NUM> (not shown). The folding systems <NUM> in the seat and leg body, <NUM>, <NUM> are coupled and controlled by the same motor M1. This advantageously allows for the simultaneous folding/unfolding of both the seat and the leg bodies <NUM>, <NUM>. The following description of the folding and unfolding movements refer to the folding system <NUM> comprised in the seat body <NUM> however, the same applies to the folding system comprised in the leg body <NUM> and/or the footrest body <NUM> and/or the armrest body <NUM>.

During a folding movement, the vane <NUM> moves through the slot <NUM> in the PCB <NUM>. When the seat body <NUM> is completely unfolded, the vane <NUM> blocks a first opto-coupler 103a generating a signal <NUM>, whilst the other opto-couplers 103b-103d emit and receive signals <NUM>. When the seat body <NUM> is completely folded, the vane <NUM> a blocks a further opto-coupler 103d. In this particular embodiment, the vane <NUM> blocks only one opto-coupler 101a, 101b, 101c, 101d, at any one time.

<FIG> shows the position of the vane <NUM> when blocking the opto-coupler 103c.

With reference to <FIG> and <FIG>, table <NUM> below shows the implementation of the various speed profiles s1, s2, s3 in terms of their corresponding opto-coupler logic states.

These logic states are provided as illustrative examples and are not to be interpreted as restrictive in any way.

A control unit (C1) is comprised in a drive unit of the stairlift <NUM> and is adapted to control the folding process. To begin a folding movement, a first speed profile s1 is initiated by the motor M1 (see <FIG>). The first opto-coupler 103a is blocked by the vane <NUM> - shown in <FIG>. The folding begins with a gradual accelerating speed until the vane <NUM> blocks a second opto-coupler 103b. At this stage, a second speed profile s2 is initiated by the same motor M1, and the folding continues with a substantially constant speed until the vane <NUM> blocks a third opto-coupler 103c. Now a third speed profile s3 is initiated at the motor M1 and the folding movement continues with a decreasing speed until the vane <NUM> blocks a fourth opto-coupler 103d. This represents the completion of the folding movement.

An unfolding process follows the same sequence but in reverse, i.e., a first speed profile s1 is initiated at the motor M1, and will see an acceleration in speed as the vane <NUM> moves away from the fourth opto-coupler 103d to unblock it. A second speed profile s2 is then initiated and unfolding continues at a constant speed until the vane <NUM> no longer blocks the third opto-couper 103c. A third speed profile s3 is intitated so that the unfolding proceeds at a decelerated speed until it unblocks the second opto-coupler 103b. The unfolding process is considered complete when the first opto-coupler 103a is the only opto-coupler that remains blocked.

In an embodiment of the invention not shown in the figures, the folding system <NUM> for folding the footrest body <NUM> is coupled to the already coupled folding systems 100c for folding the seat body <NUM> and the leg body <NUM> in such a way that when the footrest body <NUM> is in the down position, and the seat body <NUM> and leg body <NUM> are folded up, the footrest body <NUM> will fold also. The footrest body <NUM> is controlled by a motor M2. It could also be that the footrest body <NUM> folds simultaneously with the seat and leg body <NUM>, <NUM> if the required control signals are given at the respective motors M1, M2. When the folding of the footrest body <NUM> is coupled to the folding system 100c for the seat body <NUM> as well as being coupled to the folding system 100c for the leg body <NUM>, the control unit C1 sends a control signal to the motor M1 and the motor M2 (see <FIG>) The folding system <NUM> for the footrest body <NUM> is the same as described for the seat body <NUM> in <FIG>. The folding and unfolding of the footrest <NUM> follows the same process, i.e., implements the same speed profiles s1, s2, s3, as outlined in any one of the embodiments presented in the previous figures.

Claim 1:
A stairlift (<NUM>), comprising
- a rail (<NUM>),
- a stairlift unit (<NUM>) having a chair (<NUM>) and a carrier (<NUM>), wherein the carrier (<NUM>) is adapted to drive along the rail (<NUM>), and the chair (<NUM>) is supported by the carrier (<NUM>),
the chair (<NUM>) comprising a plurality of foldable parts, said foldable parts including:
- a seat body (<NUM>), foldably fixed by means of a seat joint (<NUM>) to a base body (<NUM>), wherein the base body (<NUM>) is fixed to the carrier (<NUM>);
- a leg body (<NUM>), foldably fixed to the seat body (<NUM>) by means of a leg joint (<NUM>);
- a footrest body (<NUM>), foldably fixed to the leg body (<NUM>) by means of a footrest joint (<NUM>);
- an armrest body (<NUM>), foldably fixed to a backrest body (<NUM>);
wherein the seat body (<NUM>), the leg body (<NUM>) and the footrest body (<NUM>):
- each comprise a folding system (<NUM>) which is adapted to fold and unfold at least one of the seat body (<NUM>), the leg body (<NUM>), the footrest body (<NUM>);
characterized in that
each folding system (<NUM>) is adapted to be controlled via an assigned motor (M1, M2) of the stairlift; the stairlift comprises a first motor (M1) and a second motor (M2), wherein each motor (M1, M2) is adapted to control the corresponding folding system (<NUM>) according to a variable speed profile, wherein the first motor (M1) is adapted to control the folding system (<NUM>) comprised in the seat body (<NUM>) and the folding system (<NUM>) comprised in the leg body (<NUM>), wherein the second motor (M2) is adapted to control the folding system (<NUM>) comprised in the footrest body (<NUM>).