CONTROL OF POWERED FURNITURE

COMMANDE D'UN ELEMENT DE MOBILIER ANIME

English Abstract

Furniture (typically a chair or bed) is powered to be movable between a first
and a second configuration. A detector arrangement detects the presence of
foreign bodies in the vicinity of the furniture piece, the detector
arrangement being connected to a controller arranged to modify the output of
the driver driving the furniture where a foreign body is detected.

French Abstract

Un élément de mobilier (plus spécifiquement un fauteuil ou un lit) est animé de manière à passer d'une première configuration à une deuxième configuration. Un système de détecteur détecte la présence de corps étrangers au voisinage de l'élément de mobilier, ce système de détecteur étant relié à un dispositif de commande conçu pour modifier la sortie de l'organe de commande qui commande l'élément de mobilier lorsqu'un corps étranger est détecté.

Claims

Claims:

1. A detector arrangement for furniture comprising a
furniture piece movable between a first configuration
and a second configuration, motive means for moving
the furniture between the first and second
configurations, and control means controlling the
operation of the motive means; said detector
arrangement being for detecting the presence of
foreign bodies in the vicinity of the furniture
piece, and being connected to the control means, said
detector arrangement comprising elongate electrical
contacts, the control means being arranged to modify
the output of the motive means both in the case that
the contacts break along their length and in the case
that they come into contact.

2. Furniture including the detector arrangement of claim
1.

3. A detector arrangement for furniture comprising a
furniture piece movable between a first configuration
and a second configuration, motive means for moving
the furniture between the first and second
configurations, and control means controlling the
operation of the motive means; said detector
arrangement being for detecting the presence of
foreign bodies in the vicinity of the furniture
piece, and being connected to the control means, the




control means being arranged to modify the output of
the motive means where a foreign body is detected,
said detector arrangement comprising an elongate
flexible detector switch capable of being extended
continuously about a base, or base mount or plinth,
of said furniture so as to have elongate portions
extending in substantially mutually perpendicular
directions.

4. Furniture according to claim 2, wherein the detector
arrangement comprises electrical contacts, the
control means being arranged to modify the output of
the motive means in response to change in the contact
status of the detector arrangement.

5. Furniture including the detector arrangement of claim
3 or claim 4.

6. Furniture according to claim 2 or claim 5, arranged
to detect the presence of foreign bodies positioned
between the furniture piece and the floor or wall of
a building.

7. Furniture according to claim 2, claim 5 or claim 6,
wherein the detector arrangement is arranged to
detect the presence of foreign bodies positioned
between furniture piece and a plinth or base of the
furniture piece, relative to which the furniture
piece is moveable.



8. Furniture according to claim 2 or any one of claims
to 7, wherein the furniture further comprises a
base mount or plinth for supporting the movable
furniture piece, and relative to which the furniture
piece is movable.

9. Furniture according to claim 8, wherein the furniture
piece is movable relative to the plinth or base by
tilting.

10. Furniture according to claim 2 or any one of claims
5 to 9, wherein the detector arrangement is
positioned on a portion of the arrangement which
remains substantially stationary whilst the furniture
piece moves between the first and second
configurations.

11. Furniture according to claim 2 or any one of claims
2 to 10, wherein the furniture further comprises a
base mount or plinth for supporting the movable
furniture piece, and relative, to which the furniture
piece is movable, the elongate flexible detector
extending about the base mount or plinth.

12. Furniture according to claim 2 or any one of claims
S to 10, wherein the furniture further comprises a
base mount or plinth for supporting the movable
furniture piece, and relative to which the furniture
piece is movable, the elongate flexible detector
extending about a base or plinth contacting portion
of the furniture piece.



13. Furniture according to claim 2 or any one of claims
to 12, wherein the detector arrangement comprises
electrical contacts normally biassed away from one
another but capable of being brought into contact by
an applied operating force which is substantially in
the range 5N or less.
14. Furniture according to claim 2 or any one of claims
5 to 13, wherein the detector arrangement includes an
elongate housing resiliently compressible in a
direction transverse to its longitudinal direction,
which housing carries an elongate electrical contact.
15. Furniture according to claim 14, wherein the contact
is received in a receiving formation of the housing
which receiving formation is arranged to releasably
retain the contact.
16. Furniture according to claim 15, wherein the contact
is retained in releasable gripping engagement by the
receiving formation.
17. Furniture according to any of claims 14 to 16,
wherein a second contact extends adjacent the first
contact in the housing.
18. Furniture according to claim 17, wherein the second
contact is received in a channel provided in a base
portion of the housing.




19. Furniture according to any of claims 14 to 18,
wherein at least one of the contacts comprises an
electrically conductive wire wound about an elongate
flexible former.
20. Furniture according to claim 2 or any one of claims
to 19, wherein the motive means is caused to cease
operation or reverse in operation in response to
output from the detector arrangement.
21. Furniture according to claim 20, wherein, the motive
means is caused to reverse in operation before
ceasing operation.
22. Furniture according to any one of claims 2 to 21,
wherein the motive means is arranged to operate the
furniture piece to tilt between the first and second
configuration.
23. Furniture according to claim 2 or any one of claims
5 to 22, comprising a tilting chair or bed
arrangement, said detector switch extending about the
base of the bed or chair, or (more preferably) the
base mount or plinth and having elongate portions
extending in substantially mutually perpendicular
directions.
24. Furniture according to claim 23, wherein the chair or
bed is connected to the base mount or plinth at a
tilt axis connection.




25. Furniture according to claim 24, wherein, the motive
means is arranged to extend and retract a pivotal arm
connected to the bed or chair and the base mount or
plinth.
26. Furniture substantially as herein described with
reference to the accompanying drawings.
27. A detector arrangement substantially as herein
described with reference to the accompanying
drawings.
28. A method of assembling a detector arrangement for
furniture, comprising a furniture piece moveable
between a first configuration and a second
configuration, motive means for moving the furniture
between the first and second configuration, and
control means controlling the operation of the motive
means, detector arrangement being for detecting
foreign bodies in the vicinity of the furniture
piece, the method comprising the steps of applying a
single elongate flexible detector switch along at
least two differently oriented portions of the area
to be monitored and connecting said switch to said
control means.
29. A method of assembling a detector arrangement for
furniture, the method being substantially as herein
described with reference to the accompanying
drawings.

Description

CA 02349362 2001-04-26
WO 00/25636 PCT/GB99/03614
_._
Control of ?owered Furniture
The present invention relar.ec. to the control of powered
furniture.
Chairs, beds and other Furniture are available which
include mechanisms and power units that enable the
occupant to be moved. These devices are particularly
useful for people with physical disabilities and typically
have the power to lift as much as 250kg. The same power
is typically available when the mechanism is lowered or
closed. It is normal thG~ when the mechanism is in its
raised position, access can be gained to the workings of
the mechanism. This access is not necessarily required,
but is inherent in the design of such mechanisms. It is
possible that a person, small child, animal or equipment
such as a power cord may have moved into a position where
injury or damage may occur if the mechanism is
subsequently lowered.
Improved furniture has now been devised.
According to a first aspect, the invention provides
furniture comprising:
i') a furniture piece movable between a first
configuration and a second configuration;
ii) motive means for moving the furniture between
the first and second configurations;


CA 02349362 2001-04-26
WO 00/25636 PCT/GB99/03614
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iii) control means controlling the operation of the
motive means; and,
iv) a detector arrangement for detecting the
presence of foreign bodies in the vicinity of
the furniture piece, the detector arrangement
being connected to the control means and
arranged to modify the output of the motive
means where a foreign body is detected.
The detector arrangement is preferably arranged to detect
the presence of foreign bodies positioned between the
furniture piece and the floor or wall of a building, or
more preferably, the furniture piece and a plinth or base
of the furniture piece, relative to which the furniture
piece is moveable.
The furniture therefore preferably comprises a base mount
or plinth for supporting the movable furniture piece, and
relative to which the furniture piece is movable,
preferably by tilting.
Desirably, the detector arrangement is positioned on a
portion of the arrangement which remains substantially
stationary whilst the furniture piece moves between the
first and second configurations.
The detector arrangement preferably comprises a an
elongate flexible detector, desirably extending about the
base mount or plinth or the base or plinth "contacting
portion of the furniture piece.


CA 02349362 2001-04-26
WO 00/25636 PCT/GB99/03614
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The detector arrangement comprises electrical contacts
normally biassed away from one another buy capable of
being brought .into contact by_~ry.applied operating force
which is substantially in the range 5N or less.
The detector arrangement preferably comprises an elongate
housing resiliently compressible in a direction transverse
to its longitudinal direction, which housing preferably
carries an elongate electrical contact. The contact is
preferably received in a receiving formation of the
housing which receiving formation is preferably arranged
to releasably retain the contact, desirably in releasable
gripping engagement. A second contact desirably runs
adjacent the first contact in the housing desirably
received in a channel provided in a base portion of the
housing.
In one embodiment at least one of the contacts may
comprise an electrically conductive wire wound about an
elongate flexible former. It is believed that a detector
arrangement as herein defined is novel and inventive per
se.
Desirably, the control means is arranged to modify the
output of the motive means in response to change in the
contact status of the detector arrangement. The motive
means is preferably caused to cease operat=on or reverse
in operation in response to output from the detector
arrangement corresponding to the contacts touching.
Desirably, the motive means is caused to -reverse in
operation before ceasing operation, in such circumstances.


CA 02349362 2001-04-26
WO 00/25636 PCT/GB99/03614
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The motive means is preferably arranged to operate the
furniture piece to tilt between the first and second
configuration.
In a preferred embodiment, the invention provides a
tilting chair or bed arrangement comprising:
i) a tilting bed or chair movable between a first
configuration and a second configuration tilted
relative to the first configuration;
ii) a base mount or plinth for the chair or bed;
iii) motive means for tilting the bed or chair from
the first to the second configuration;
iv) control means controlling the operation of the
motive means; and,
v) a detector arrangement for detecting the
presence of foreign bodies between the base
mount or plinth and the bed or chair, the
detector arrangement being connected to the
control means and arranged to modify the output
of the motive means where a foreign body is
detected, the detector means comprising an
elongate detector element extending about the
base of the bed or chair, or (more preferably)
the base mount or plinth and having elongate
portions extending in substantially mutually
perpendicular directions.


CA 02349362 2001-04-26
WO 00/25636 PCT/GB99/03614
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The chair or bed is preferably connected to the base mount
or plinth at a tilt axis connection. Desirably,.. ~he
motive means is arranged to extend and retract a pivotal
arm connected to the bed or chair and the base mount or
plinth.
The inventior~ will now be further described in a specific
embodiment, by way of example only, and with reference to
the accompanying drawings, in which:
Figure 1 is a schematic representation of an
arrangement for controlling the operation of
furniture according to the invention;
Figure 2 is a schematic sectional view of a detector
arrangement comprising furniture according to the
invention;
Figure 3 is a schematic perspective view of the
construction of a flexible continuous conductor shown
in figure 2;
Figure 4 is a schematic perspective view of a support
frame for powered tilting furniture according to the
invention; and,
Figure 5 is a view corresponding to figure 4, showing
a detector arrangement according to the invention in
position.


CA 02349362 2001-04-26
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Referring to the drawings, as shown in Figure 1, an
elongate flexible detector 1 is connected to an electronic
circuit 2, which can be interFacf~d as required to the
control unit of the powered furniture 3. The electronic
circuit comprises a monitor section 10 and a latch 11.
The detector 1 comprises two continuous metal contacts 8
and 9, supported in a rigid non-conducting base 7 and a
flexible non-conducting cover 6 as shown in Figure 2. The
cover 6 has sufficient flexibility to allow the contacts
8 and 9 to touch when pressure is applied and sufficient
recovery strength to separate the contacts 8 and 9 when
the pressure is removed. To ensure that the upper contact
8 has sufficient flexibility in all dimensions it may be
made of a thin metal material, or as shown in Figure 5 it
may be constructed as a wire 13 wound onto a non-
conducting flexible, non-stretch former 12.
Under normal circumstances, when it is safe for the
furniture to be operated (for example tilted to a lowered
position from a raised position), the output of the latch
11 in the electronic circuit 2 will be in a reset state.
The monitor 10 in the electronic circuit 2 detects if the
contacts 8 and 9 in the detector device break along their
length or if they come into contact. If either event
happens, the monitor 10 will set the output of the latch
11.
The changed output state of the latch 11 can be used by
the machine's control unit 3 to initiate the most
desirable action, for example to stop or reverse the


CA 02349362 2001-04-26
_ WO 00/25636 PCT/GB99/03614
machine's power unit 5.
The l~.tch 11 will remain with a changed output state until
the contacts 8 and 9 separate and the latch 11
subsequently receives a separate reset signal.
As an example, for the case of a lifting chair, which is
used to help the chair's occupant to stand from a sitting
position, the chair's mechanism will be opened by its
power unit 5 as shown in Figure 4. The detector 1 is
fitted to a base mount frame 14 to extend around three
sides of the frame enclosing the opening area of the
mechanism 4 as shown in Figure 5, so that any body of
sufficient weight entering the opening in the machine will
press the contacts 8 and 9 in the detector device
together. Alternatively, if an object with insufficient
weight, such as a power cord enters the mechanism, the
contacts 8 and 9 in the detector device 1 will come
together as the mechanism 4 closes on it. The amount of
movement allowed in the detector device will ensure that
damage is not caused to the obstructing object before the
mechanisms' movement is stopped or reversed.

Representative Drawing