GB2481368A

GB2481368A - Furniture controller with automatic disabling of user controls to prevent accidental operation and requiring specific input to reactivate controls

Info

Publication number: GB2481368A
Application number: GB1009499.3A
Authority: GB
Inventors: Richard Rudd
Original assignee: ELECTRIC MOBILITY EURO Ltd
Current assignee: ELECTRIC MOBILITY EURO Ltd
Priority date: 2010-06-07
Filing date: 2010-06-07
Publication date: 2011-12-28
Also published as: GB201009499D0

Abstract

A controller 10 for an item of furniture of the type having a support surface whose position or orientation is adjustable by means of an electrically controlled actuator, e.g. a rise-and-recline chair for the disabled, comprises: an electrical control, e.g. user control buttons 14,16, for adjusting the position of the support surface; means for automatically disabling the electrical control, e.g. a timer within a control circuit [42, Figure 2]; and means, e.g. vibration switch or sensor [46, Figure 2] for detecting a user input indicating that the electrical control keys 14,16 are to be enabled, wherein the means for automatically disabling the electrical control 14,16 is operative to enable the electrical control 14,16 on detection of the user input, e.g. by tapping the controller 10. By deactivating the functions keys 14,16 of the controller after a predetermined period of inactivity, accidental operation of the electric actuator within the item of furniture is prevented, e.g. inadvertent operation whilst asleep. When the actuator requires operation, the function keys 14,16 of the controller must be reactivated by tapping the controller.

Description

A CONTROLLER

Technical Field

The present invention relates to a controller for an item of furniture having one or more support surfaces whose position or orientation is adjustable by means of one or more electrically controlled actuators. The present invention is particularly suitable for so-called "rise and recline" flirniture.

Background to the Invention

Many elderly, disabled or infirm people, as well as able-bodied people, benefit from resting in a reclining position on a chair, bed, sofa or other item of furniture. To meet this need, ftirniture has been developed having support surfaces such as seats, cushions and back rests which can be moved between raised, seated and/or reclined positions by means of electric motors, hydraulic or pneumatic rams or other electrically controlled actuators which are controlled by controls such as push switches mounted on a controller which can be held and operated in one hand. Some furniture items of this type have support surfaces which can be moved to assist the user in rising or getting up from the ftirniture.

Such furniture is known as "rise and recline" flirniture.

The controllers for ftirniture of this type are typically connected to the ftirniture by means of a cable, so that they can be held in a user's hand in a comfortable position. This can give rise to problems, however, as the user may fall asleep and accidentally lean on, press or otherwise operate the controls of the controller whilst asleep. If the user inadvertently operates the "rise" control they may be ejected from the furniture, which in the case of elderly or infirm users may cause injury or even death. Inadvertent operation of the controls of the controller has also been known to cause injury and death to pets and children who may have been in, on or under the ftirniture at the time that the controls were inadvertently operated.

I

Attempts have been made to address the problem of inadvertent operation of the controls.

Some systems provide hand operated controllers with keys, such that the controls of the controller cannot be operated unless the controller is unlocked by inserting the key. This approach is ineffective, however, as the user may fall asleep or otherwise become incapacitated prior to disabling the controller with the key. A further disadvantage of this approach is that it requires a key that can be lost, and which may be difficult to manipulate, particularly for users suffering from arthritis and similar conditions. Other systems use recessed controls in the controller to reduce the risk of inadvertent operation.

However, these recessed controls can also be difficult to operate for users suffering from arthritis or similar conditions.

Summary of Invention

According to a first aspect of the present invention there is provided a controller for an item of furniture having a support surface whose position or orientation is adjustable by means of an electrically controlled actuator, the controller comprising: an electrical control for adjusting the position or orientation of the support surface; means for automatically disabling the electrical control; and means for detecting a user input indicating that the electrical control is to be enabled, wherein the means for automatically disabling the electrical control is operative to enable the electrical control on detection of the user input indicating that the electrical control is to be enabled The controller of the present invention reduces the risk of injury in the event that a user of the item of furniture accidentally or inadvertently operates the electrical control, for example by leaning on it in their sleep, as the electrical control is automatically disabled.

When the user wishes to adjust the position of the support surfaces the electrical control can quickly and easily be enabled. Thus, the present invention provides an easy to use controller which improves the safety of users of furniture of this type.

The means for detecting a user input may comprise a trigger mechanism.

For example, the trigger mechanism may comprise a vibration sensor.

The vibration sensor may comprise a flexible coil of an electrically conductive material housed in a container of an electrically conductive material, the coil being connected at one end to a first contact of the vibration sensor and the container being connected to a second contact of the vibration sensor, wherein the coil is normally electrically isolated from the container such that if the vibration sensor is subjected to shock or vibration the coil contacts an inner wall of the container to establish an electrical connection between the first contact and the second contact.

Alternatively, the trigger mechanism may be selected from the group consisting of an inertia switch, a tilt switch, a resistive bridge switch, a magnetic switch, a capacitive switch and a piezoelectric sensor.

The means for automatically disabling the electrical control may comprise a timer circuit.

The timer circuit may be operative to enable the electrical control for a predetermined time period on detection of the user input indicating that the electrical control is to be enabled.

An output of the timer circuit may control a power supply to a circuit containing the electrically controlled actuator.

For example, an output of the timer circuit may control a relay to control the power supply to the circuit containing the electrically controlled actuator.

The controller may be arranged such that if the timer circuit fails the electrical control is enabled such that the electrically controlled actuator remains operable. This ensures that a user of the item of furniture is not stranded in the event of failure of the timer circuit.

For example, the timer circuit may be arranged such that when a coil of the relay is de-energised the power supply to a circuit containing the electrical control and the electrically controlled actuator is enabled.

According to a second aspect of the invention there is provided a piece of furniture comprising a controller according to the first aspect of the invention.

Brief Description of the Drawings

Embodiments of the invention will now be described, strictly by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a schematic representation of a controller according to an embodiment of the present invention; Figure 2 is a schematic diagram showing a circuit which is suitable for use in a controller according to the present invention; and Figure 3 is a schematic representation of a vibration sensor which is suitable for use in the circuit of Figure 2.

Description of the Embodiments

Referring first to Figure 1, a controller for controlling the operation of a piece of furniture having one or more support surfaces whose position or orientation is adjustable by means of one or more electrically controlled actuators, for example a so-called "rise and recline" chair is shown generally at 10. The controller 10 has a body 12 on which are mounted electrical controls 14, 16 for adjusting the position of the support surface(s) of the piece of furniture. The controls 14, 16, which in this example are push switches, may be raised with respect to an upper surface of the body 12 to make them easy to locate and operate, or they may be substantially flush with the upper surface of the body 12.

In this example, the controller 10 includes an "up" control 14 and a "down" control 16, which are configured to operate the "rise" and "recline" functions of a rise and recline chair, but it will be appreciated that the present invention is equally applicable to controllers with more or fewer controls and to controllers for other pieces of furniture having adjustable support surfaces such as beds, sofas and the like.

The controller 10 also includes a first light emitting diode (LED) 18 which indicates that the controller 10 is connected to a power supply, and a second LED 20 which indicates when the controls 14, 16 are disabled, as will be described in more detail below. In this example an electrical cable 22 extends through an opening in one end of the body 12 and is used to connect the controller 10 to a piece of furniture by means of an appropriate plug or other connector. However, it will be appreciated that the controller 10 may be connected wirelessly to the piece of furniture using a radio frequency (RF) link or a wireless protocol such as Bluetooth, for example. The controlled 10 may alternatively form part of the piece of furniture to which it is connected. For example, the controller 10 may be built into an arm of a chair, sofa or the like.

The controller 10 includes an electronic circuit which disables the controls 14, 16 until a user input indicating that the controls 14, 16 are to be enabled is received by the electronic circuit. In one example, the user indicates that the controls are to be enabled by tapping the body 12 of the controller 10 against an object such as a hand or a part of the piece of the furniture to which the controller is connected. Once this user input has been received, the electronic circuit enables the controls 14, 16 for a predetermined period of time, for example ten minutes, after which the electronic circuit disables the controls 14, 16. In this way, a user of a piece of furniture to which the controller 10 is connected can adjust the position of the support surface(s) of the piece of furniture at will, by enabling the controls 14, 16, but the risk of accidental or inadvertent operation of the controls 14,16, for example if the user falls asleep and leans on the controller 10, is reduced, as the controls 14, 16 are automatically disabled after a predetermined period.

Turning now to Figure 2, a suitable electronic circuit is shown, in a schematic form, generally at 40. The circuit 40 is based around a 555 timer integrated circuit (IC) 42 which is configured to operate as a monostable multivibrator.

The IC 42 is connected to a DC power supply having positive and ground rails, which is provided by a voltage regulator (not shown). A control voltage (CV) input of the IC 42 is connected to the ground rail through a decoupling capacitor 44, whilst positive (V+) and ground (GND) inputs of the IC are connected, respectively, to the positive and ground supply rails.

A trigger input (TR) of the IC 42 is connected to a vibration sensor or switch 46 which is mounted in the body 12 of the controller 10, such that the vibration sensor or switch 46 provides an input to trigger the IC 42 when the controller 10 is tapped against an object.

A suitable vibration sensor or switch 46 is described below with reference to Figure 3, but it will be appreciated that any suitable device or circuit can be used as the vibration sensor or switch 46. For example, a trigger mechanism based on or incorporating an inertia switch, a tilt switch, a resistive bridge switch, a magnetic switch, a capacitive switch or a piezoelectric sensor may be employed.

The IC 42 is triggered by the falling edge of a trigger pulse. To reduce the risk of accidental triggering of the IC 42, a resistor 48 is connected at one end to the positive power supply rail and at the other end to the trigger input (TR) of the IC 42 and to the vibration sensor or switch 46. Thus, only when the vibration sensor or switch 46 is activated will there be a trigger pulse to trigger the IC 42.

A coil 50 of a relay 52 is connected between the positive power supply rail and an output (OP) of the IC 42. As is conventional, a diode 54 is connected in parallel with the coil of the relay 52 to protect the IC 42 from back EMF generated when the coil 50 de-energises.

A moveable armature 56 of the relay 52 is connected to a positive power supply for a motor control circuit to which the controls 14, 16 belong, and which includes one or more electrically controlled actuator, such as an electric motor or an electrically controlled hydraulic or pneumatic ram. A first stationary contact 58 of the relay 52 is unconnected and is thus open circuit, whilst a second stationary contact 60 of the relay 52 is connected to a positive power supply rail of the motor control circuit. Thus, the relay 52 controls the power supply to the motor control circuit.

In normal operation of the circuit 40, the output (OP) of the IC 42 is low, i.e. at or close to 0 volts. Thus current can flow from the positive power supply rail through the coil 50 to the output (OP) of the IC 42, which acts as a current sink. This current energises the coil 50 of the relay 52, causing the moveable armature 56 of the relay to be drawn towards the open-circuit first stationary contact 58. Thus, in normal operation of the circuit 40 the power supply to the motor control circuit is interrupted and the controls 14, 16 are disabled.

When the output (OP) of the ic 42 is positive, there is no current path through the coil 50 of the relay 52, and thus the coil is de-energised. The moveable armature 56 is biased towards the second stationary contact 60, and thus when the coil 50 is de-energised the moveable armature 56 returns to a default position in which it is in contact with the second stationary contact 60. In this condition the power supply to the motor control circuit is re-established and the controls 14, 16 are enabled.

The LED 20 is connected between the positive power supply rail of the circuit 40 and the to the output (OP) of the IC 42, with a resistor 62 being provided in series with the LED to limit the current flowing through the LED 20, as is conventional. In this example the LED 20 is a self-flashing LED, but it will be appreciated that the LED 20 may be any suitable type of LED.

The LED 20 is activated when the output (OP) of the IC 42 is low, as a current path exists from the positive power supply rail to the output (OP) of the IC 42, which acts as a current sink. Thus, the LED 20 indicates when the controls 14, 16 are disabled, in this example by flashing at a predetermined rate.

A resistor 64 and a capacitor 66 are connected in series between the positive and ground power supply rails of the circuit 40. Threshold (THR) and discharge (DCH) inputs of the IC 42 are connected between the series resistor 64 and capacitor 66 such that the resistor 64 and capacitor 66 set the period for which the output (OP) of the IC 42 is positive once the IC 42 has been triggered by an appropriate trigger signal from the vibration sensor or switch 46, and thus the period for which the controls 14, 16 are enabled once the controller 10 has been tapped. The values of the resistor 64 and capacitor 66 are selected so as to provide an appropriate time period such as ten minutes.

In operation of the circuit 40, the vibration sensor or switch 46 provides a trigger pulse to the trigger (TR) input of the ic 42 when the controller 10 is tapped. The negative-going or falling edge of this trigger pulse causes the output (OP) of the IC 42 to go high for a period determined by the series resistor 64 and capacitor 66.

As is described above, when the output (OP) of the IC 42 is high, the LED 20 is deactivated and the coil 50 of the relay 52 is de-energised, causing the armature 56 to come into contact with the second stationary contact 60, thereby completing the power supply to the motor control circuit and enabling the controls 14, 16, allowing the position of the support surface(s) of the item of furniture to which the controller 10 is connected to be adjusted by the user.

At the end of the time period determined by the values of the resistor 64 and the capacitor 66 the output (OP) of the IC 42 goes low, re-establishing the current path through the coil of the relay 52. Thus, the coil 50 is energised, causing the armature 56 to move into contact with the open-circuit first stationary contact 58, thereby isolating the motor control circuit from its power supply and disabling the controls 14, 16. The current path through the LED 20 is also re-established, so the LED 20 is reactivated to provide a visual indication that the controls 14, 16 are disabled.

It will be appreciated that the circuit 40 provides a fail safe mechanism such that in the event of failure of the circuit 40, for example if its power supply is interrupted, the power supply to the motor control circuit will be re-established, since the default condition of the relay 52, i.e. when the coil 50 is de-energised, is for the armature 56 to contact the second stationary contact 60. Thus, in the event of failure of the circuit 40 the controls 14, 16 will be enabled, allowing the position of the support surface(s) of the item of furniture to be adjusted, thereby removing any risk that a user of the item of furniture could be stranded and unable to get off the item of furniture in the event of failure of the circuit 40.

Turning now to Figure 3, a vibration switch or sensor suitable for use in the circuit of Figure 2 is shown generally at 80. The vibration switch or sensor 80 includes a hollow can or container 82 of an electrically conductive material such as copper or aluminium, in which a flexible coil or spring 84 of an electrically conductive material is housed. The coil or spring 84 is attached at a first end to a base of the can, with its opposite end being free. The first end of the coil or spring 84 is electrically connected to a first contact lead 86, and is electrically isolated from the container or can 82, whilst the container or can 82 is electrically connected to a second contact lead 88.

If the vibration switch or sensor 80 is subjected to a shock or vibration, for example by tapping a controller 10 in which the vibration switch or sensor 80 is housed, the coil or spring 84 flexes and moves into contact with an inner wall of the container or can 82, thereby establishing an electrical connection between the first and second contact leads 86, 88. Thus the vibration switch or sensor 80, when used as the vibration switch or sensor 46 in the circuit of Figure 2, can provide a trigger pulse to trigger the IC 42.

Although in the exemplary embodiment described above a 555 timer IC forms the basis of the circuit 40, it will be appreciated that other triggerable monostable timer ICs, or indeed an electronic circuit composed of discrete components, could be used in place of the 555 timer IC 42.

Similarly, although the vibration sensor or switch 80 described above with reference to Figure 3 is particularly suitable for use in the controller of the present invention, it will be appreciated that other suitable sensors or switches could be used in its place. Indeed, the vibration switch or sensor 46 used in the circuit of Figure 2 could be replaced by another user input device, such as a push switch, sound detector or voice activation system, although a vibration sensor or switch as described above is preferred, since it provides a simple and effective means of enabling the controls 14, 16.

Although the controller of the present invention has been described as being suitable for use in conjunction with "rise and recline" furniture used, for example by the elderly or infirm, it will be appreciated that it is equally suitable for use in other applications in which a manually operable controller is required, for example in domestic furniture, electrically operated stair lifts, bath lifts and the like.

Claims

CLAIMS1. A controller for an item of furniture having a support surface whose position or orientation is adjustable by means of an electrically controlled actuator, the controller comprising: an electrical control for adjusting the position or orientation of the support surface; means for automatically disabling the electrical control; and means for detecting a user input indicating that the electrical control is to be enabled, wherein the means for automatically disabling the electrical control is operative to enable the electrical control on detection of the user input indicating that the electrical control is to be enabled.
2. A controller according to claim 1 wherein the means for detecting a user input comprises a trigger mechanism.
3. A controller according to claim 2 wherein the trigger mechanism comprises a vibration sensor.
4. A controller according to claim 3 wherein the vibration sensor comprises a flexible coil of an electrically conductive material housed in a container of an electrically conductive material, the coil being connected at one end to a first contact of the vibration sensor and the container being connected to a second contact of the vibration sensor, wherein the coil is normally electrically isolated from the container such that if the vibration sensor is subjected to shock or vibration the coil contacts an inner wall of the container to establish an electrical connection between the first contact and the second contact.
5. A controller according to claim 2 wherein the trigger mechanism is selected from the group consisting of an inertia switch, a tilt switch, a resistive bridge switch, a magnetic switch, a capacitive switch and a piezoelectric sensor.
6. A controller according to any one of the preceding claims wherein the means for automatically disabling the electrical control comprises a timer circuit.
7. A controller according to claim 6 wherein the timer circuit is operative to enable the electrical control for a predetermined time period on detection of the user input indicating that the electrical control is to be enabled.
8. A controller according to claim 6 or claim 7 wherein an output of the timer circuit controls a power supply to a circuit containing the electrically controlled actuator.
9. A controller according to claim 7 or claim 8 wherein an output of the timer circuit controls a relay to control the power supply to the circuit containing the electrically controlled actuator.
10. A controller according to any one of claims 7 to 9 wherein the controller is arranged such that if the timer circuit fails the electrical control is enabled such that the electrically controlled actuator remains operable.
11. A controller according to claim 9 or claim 10 wherein the timer circuit is arranged such that when a coil of the relay is de-energised the power supply to a circuit containing the electrical control and the electrically controlled actuator is enabled.
12. A controller substantially as hereinbefore described with reference to the accompanying drawings.
13. A piece of furniture comprising a ccolroller according to any one of clafrn* 1 to 12.Amendment to the claims have been filed as followsCLAIMS1. A controller for an item of furniture having a support surface whose position or orientation is adjustable by means of an electrically controlled actuator, the controller comprising: an electrical control for adjusting the position or orientation of the support surface; means for automatically disabling the electrical control; and a vibration sensor for detecting a user input indicating that the electrical control is to be enabled, wherein on detection of the user input a timer is triggered to enable the electrical control for a predetermined period of time.2. A controller according to claim 1 wherein the vibration sensor comprises a flexible coil of an electrically conductive material housed in a container of an electrically conductive material, the coil being connected at one end to a first contact of the vibration sensor and the container being connected to a second contact of the vibration sensor, wherein the coil is normally electrically isolated from the container such that if the Q vibration sensor is subjected to shock or vibration the coil contacts an inner wall of the container to establish an electrical connection between the first contact and the second contact.3. A controller according to claim 1 or claim 2 wherein an output of the timer circuit controls a power supply to a circuit containing the electrically controlled actuator.4. A controller according to claim 3 wherein an output of the timer circuit controls a relay to control the power supply to the circuit containing the electrically controlled actuator.5. A controller according to any one of claims 1 to 4 wherein the controller is arranged such that if the timer circuit fails the electrical control is enabled such that the electrically controlled actuator remains operable.6. A controller according to claim 4 wherein the timer circuit is arranged such that when a coil of the relay is de-energised the power supply to a circuit containing the electrical control and the electrically controlled actuator is enabled.7. A controller substantially as hereinbefore described with reference to the accompanying drawings.8. A piece of furniture comprising a controller according to any one of claims ito 7. (\J*::r: INTELLECTUAL 16 . ... PROPERTY OFFICE Application No: GB 1009499.3 Examiner: Barnaby Wright Claims searched: 1-13 Date of search: 28 September 2010 Patents Act 1977: Search Report under Section 17 Documents considered to be relevant: Category Relevant Identity of document and passage or figure of particular relevance to claims X l,6,7at GB2384173 A least (SMARTASYSTEMS) See whole doc., esp. p1, ln 27-34, and Figs. 1-X 1, 2 at US 2003/0209924 Al least (BAUER) See whole doc, noting controller for seat adjustment with means 48 for detecting that a user wishes to use electric control buttons 46, the means 48 being part of a disabling arrangement that automatically disables buttons 46.X 1,2,5 at US2009/0126115Al least (DOERING) See whole doc., noting use of acceleration sensors or proximity sensors to detect an intention to use remote controller.X 1,2,6at DE20105656U1 least (MEDICAL GMBH) See esp. WPI Abstract Accession No. 200 1- 523744 [58], and Fig 1. Control device is automatically disabled after set period of inactivity. A reset command is required to reactivate controller.X 1, 2, 5-7 US 2009/0002217 Al at least (KRYZE) See whole doc. esp. para [0003] to [0004], [0037] and [0039].X 1 and 6 EP 1754462 A2 (HILL ROM) See whole doc., eps. para [0321].Categories: X Document indicating lack of novelty or inventive A Document indicating technological background and/or state step of the art.Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of before the filing date of this invention.same category.& Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:Search of GB, EP, WO & US patent documents classified in the following areas of the UKCX Worldwide search of patent documents classified in the following areas of the IPC A47C; A61G; F16P Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk *::r: INTELLECTUAL 17 . .... PROPERTY OFFICE The following online and other databases have been used in the preparation of this search report EPODOC, WPI; TXTE International Classification: Subclass Subgroup Valid From A47C 000 1/024 01/01/2006 A61G 0005/14 01/01/2006 A61G 0007/018 01/01/2006 Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk