Remote control system for controlling a domestic appliance

The present invention relates to a remote control system for controlling a domestic appliance . In particular, the present in- vention relates to a remote control system for controlling a cooking appliance. Preferably, the present invention relates to a remote control system for controlling a cooking hob. Further, the present invention relates to a method for controlling a domestic appliance by at least one remote device.

A remote control of many domestic appliances is not generally allowed due to legal safety issues. In particular, the remote control of a cooking hob is not allowed. However, the control of domestic appliances by remote device, e.g. smartphones or tab ^¬ lets, is increasing and desired by many users. The control of the domestic appliance by the remote device could be allowed, if the distance between the user and the domestic appliance would be controlled to be within a safe value in order to allow a man ^¬ ual control of the domestic appliance.

It is an object of the present invention to provide a remote control system for controlling a domestic appliance, wherein the distance between the domestic appliance and a user is reliably controlled by low complexity.

The object is achieved by the remote control system for control ^¬ ling a domestic appliance according to claim 1.

According to the present invention a remote control system for controlling a first domestic appliance is provided, wherein: - the remote control system comprises the first domestic ap ^¬ pliance and at least one remote device, - the first domestic appliance is connected to the remote de ^¬ vice via an acoustic connection, and

- the first domestic appliance is controllable by the remote device, if a predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is recognised by said remote device.

The main idea of the present invention is that the first domes ^¬ tic appliance, which may be a cooking hob, is controllable by the remote device only, if the predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is recognised by said remote device. Effectively, the first domestic appliance is controllable by the remote device, if the distance between the remote control and the first domes- tic application does not exceed a predetermined value. There may be a sound level and/or an oscillation amplitude provided or predefined which may not be exceeded in order to ensure that the distance is kept within a predetermined value. The sound signal may be a sound seguence, e. g. a seguence of tones or the like.

The acoustic connection, or the sound signal, respectively, may either be within the audible range, which enables the user of the system to listen to the transmission of the sound signal, and in that to control the functionality. Alternatively, a non- audible level may be used, what is advantageous for a user who dislikes to be disturbed by a noisy environment.

Preferably, the first domestic appliance is controllable by the remote device, if the predefined sound signal from the first do mestic appliance to the remote device via the acoustic connec ^¬ tion is recognised by said remote device within a predefined time interval, after a control command has been sent from the remote device to the first domestic appliance. In contrast it may be provided, that the first domestic appliance is not controllable by the remote device, if the predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is not recognised by said re- mote device within the predefined time interval, after the control command has been sent from the remote device to the first domestic appliance.

In particular, the acoustic connection is a unidirectional con- nection from the first domestic appliance to the remote device.

A preferred embodiment of a remote device may be a smartphone, a tablet, a notebook or the like. Generally, it could be any device with smart control functionality, also a personal computer.

A particularly favourable embodiment of the remote control system comprises at least one device or second domestic appliance arranged in a joint network with the first domestic appliance, in particular a local network and/or a smart home network, wherein the first domestic appliance is connected to the device or to the second domestic appliance via a first connection, the remote device is connected to the device or second domestic appliance via a second connection, and the first domestic appliance is controllable by the remote device via the device, if the predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is recognised by said remote device.

It may be further provided that the first domestic appliance is controllable, in particular only controllable, by the remote device if the predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is recognised by said remote device within a predefined time interval, after a control command has been sent from the remote device to the first domestic appliance via the route comprising the second wireless connection, the device or second domestic appliance and the first wireless connection.

The device which is arranged m the joint network with the firs domestic appliance may be a network coupling device, which may be a router or a digital assistant adapted to receive, to process and/or to transmit commands.

Advantageously, the first connection between the first domestic appliance and the device or second domestic appliance is a wireless local area network (WLAN) connection or a local area network connection. Additionally or alternatively, the second connection between the at least one remote device and the device or second domestic appliance may be a wireless local area network (WLAN) .

Preferably, at least one of the first connection and the second connection is a Wi-Fi connection.

In particular, the remote device includes application software for generating the control command and/or for recognising the predefined sound signal. One possibility for a sound signal transfer may be a mere sending of a seguence of tones or a seguence of a melody. Another option may be a use of a transmission via acoustic wave modulation on amplitude or freguency, a measure for a specification of this interaction. Such kind of acoustic wave modulation may be varied even within only one or very few sound signals or tones . Further, filtering means may be used within the remote device allowing identification and suppression of noises in the sound signal sent from the first domestic appliance. In order to avoid that the first domestic appliance is opened up or unblocked for any kind of communication, what may cause a loss of control, the acoustic connection is preferably secured by a unique identification signal or any other kind of identi- fier which is added to the predefined sound signal or which is modulating or modifying the predefined sound signal.

Further, the present invention relates to a method for controlling a first domestic appliance by at least one remote device, wherein the first domestic appliance is connected to the remote device via an acoustic connection, and wherein the method comprises the steps of:

- sending a control command from the remote device to the domestic appliance,

- sending a predefined sound signal from the first domestic appliance to the remote device via the acoustic connection,

- if the predefined sound signal is recognised by the remote device within a predefined time interval, then the first do mestic appliance is controllable by said remote device, and

- if the predefined sound signal is not recognised by the remote device within the predefined time interval, then the domestic appliance is not controllable by said remote device . Preferably, the predefined sound signal is a predefined sequence of tones.

In particular, the predefined time interval is between one and five seconds, preferably between two and four seconds, in par- ticular three seconds.

Moreover, the predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is repeated a number of times, after the control command from the remote device to the domestic appliance has been sent, wherein preferably the predefined sound signal is repeated one, two or three times . In particular, the method is provided for the remote control system mentioned above.

The first domestic appliance is preferably controlled by the re ^¬ mote device via a device or a second domestic appliance arranged in a joint network with the first domestic appliance, wherein the first domestic appliance is connected to the device or sec ^¬ ond domestic appliance via a first connection, the remote device is connected to the device or second domestic appliance via a second connection and the first domestic appliance is controlla- ble by the remote device via the device or the second domestic appliance if the predefined sound signal from the first domestic appliance to the remote device via the acoustic connection is recognised by the remote device. The joint network for the first domestic appliance and the de ^¬ vice or second domestic appliance may be a local network and/or a smart home network.

A particularly preferred method is defined by an acoustic con- nection which further comprises a unigue identification signal, or the like, which is added to the predefined sound signal and/or is modulating or modifying in whatever way the predefined sound signal. With such kind of measure, the security in con ^¬ trolling the first domestic appliance is increased. The unigue identification signal may be a repetitive signal, more pre ^¬ ferred, however, is a unigue identification signal which is randomly created by the first domestic appliance. It may be beneficial to record and transform the unique identi ^¬ fication signal by the remote device and to add the transformed unique identification signal to a control message, in particular to each control message, sent from the remote device to the first domestic appliance for a program or program parameter controlling. It is further beneficial to provide for the first do ^¬ mestic appliance to only accept a control message when it re ^¬ ceives the transformed unique identification signal in addition. Novel and inventive features of the present invention are set forth in the appended claims .

The present invention will be described in further detail with reference to the drawing, in which

FIG 1 illustrates a schematic perspective view of a remote con ^¬ trol system for controlling a domestic appliance accord ^¬ ing to a preferred embodiment of the present invention. FIG 1 illustrates a schematic perspective view of a remote con ^¬ trol system for controlling a domestic appliance 10 according to a preferred embodiment of the present invention. The remote con ^¬ trol system comprises the domestic appliance 10, a remote device 12 and a router 14. In this example, the domestic appliance 10 is a cooking hob 10. In particular, the remote device 12 is a smartphone, a tablet, a notebook or the like.

The cooking hob 10 and the router 14 are connected via a first wireless connection 18. Preferably, the first wireless connec- tion 18 is a wireless local area network (WLAN) connection. Alternatively, the cooking hob 10 and the router 14 may be con ^¬ nected via a local area network (LAN) connection. Further, the remote device 12 is connected to the router 14 via a second wireless connection 22. Preferably, the second wireless connection 22 is a wireless local area network (WLAN) connection. In particular, the first wireless connection 18 and/or the second wireless connection 22 are Wi-Fi connections.

Further, the cooking hob 10 and the remote device 12 are connected via an acoustic connection 20. Said acoustic connection 20 is a unidirectional connection from the cooking hob 10 to the remote device 12. The cooking hob 10 includes a sound generating device, while the remote device 12 includes a microphone and a sound checking device. Said acoustic connection 20 provides an acoustic feedback from the cooking hob 10 to the remote device 12 in order to verify, if the remote device 12 is located inside a control range 16. Said control range 16 is a predefined area around the cooking hob 10. If the remote device 12 is located inside the control range 16, then the cooking hob 10 is controllable by said remote device 12. If the remote device 12 is located outside the control range 16, then the cooking hob 10 cannot be controlled by said remote device 12.

The remote device 12 sends a control command via the second wireless connection 22 and the first wireless connection 18 to the cooking hob 10 to send a predefined sound signal via the acoustic connection 20 to the remote device 12. The remote de- vice 12 includes the microphone for receiving the sound signal and the sound checking device for checking said sound signal. If the remote device 12 recognises the sound signal within a predetermined time interval, then the remote device 12 is located inside the control range 16 and the cooking hob 10 is controllable by said remote device 12. For example, the predetermined time interval is three seconds. However, if the remote device 12 does not recognise the sound signal within the predetermined time interval, then the cooking hob 10 cannot be controlled by said remote device 12. Alternatively or additionally to the predetermined time interval, the recognition whether the remote device 12 is located inside the control range 16 or not may also be controlled by means of a predefined sound level and/or oscillation amplitude and/or power level for the predefined sound signal which is kept below a predefined value, in that, defining the area of the control range 16. The sound signal is a predefined seguence of tones . Preferably, the sound signal is repeated a number of times, after the control command has been sent by the remote device 12. For example, the sound signal is repeated one, two or three times. The control command is created by application software in the remote device 12. Further, said application software checks the received sound signal from cooking hob 10.

In order to increase the security in controlling the cooking hob 10, the acoustic connection 20 further comprises a unigue iden- tification signal, or the like, which is added to the predefined sound signal and/or is modulating or modifying in whatever way the predefined sound signal. This unigue identification signal is randomly created by the first cooking hob 10 and transmitted to the remote device 12 together with the sound signal. The unigue identification signal is recorded and transformed by the remote device 12. The transformed unigue identification signal is then added to a control message, in particular to each control message, sent from the remote device 12 to the cooking hob for a program or program parameter controlling. The cooking hob 10 only accepts a control message when receiving from the remote device 12 also the transformed unigue identification signal, accompanying the sound signal. Although an illustrative embodiment of the present invention has been described herein with reference to the accompanying drawing, it is to be understood that the present invention is not limited to that precise embodiment, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as defined by the appended claims .

List of reference numerals

10 cooking hob

12 remote device

14 router

16 control range

18 first wireless connection

20 acoustic connection

22 second wireless connection