WO2022243701A1

WO2022243701A1 - A removable control device for communicating high resolution rotation

Info

Publication number: WO2022243701A1
Application number: PCT/GB2022/051278
Authority: WO
Inventors: Jack RAISON; Nicholas ORME; Charles Edmund STRAWBRIDGE; Nathan Edward RUTTLEY
Original assignee: Njori Ltd
Priority date: 2021-05-20
Filing date: 2022-05-20
Publication date: 2022-11-24
Also published as: GB202107227D0; GB2606756A

Abstract

A removable control device for controlling an electrical device is provide, wherein the control device comprises a first part configured to contact an electrical device, a second part configured to co- operate with the first part to enable relative rotation therewith, a rotary encoder, and communication circuitry. A relative rotation between the first part and second part causes the rotary encoder to generate a first output signal indicative of the relative rotation. The first output signal is communicated to the electrical device via the communication circuitry. The communicated first output signal may be used to control a setting, e.g. a temperature or volume setting of the electrical device.

Description

A REMOVABLE CONTROL DEVICE FOR COMMUNICATING HIGH RESOLUTION ROTATION

Field of Invention

The present invention relates to removable control devices for communicating rotation data to an electrical device. In one aspect, the removable control device comprises two pieces, wherein a relative rotation between the two pieces is communicated to an electrical device. The communicated data may be used to control a setting, e.g. a temperature or volume setting of the electrical device.

Background

A control knob, as it is colloquially known, provides an input to a mechanical or an electrical device that corresponds to a rotation of the control knob. A rotation of the control knob is used to control a corresponding setting on the mechanical/electrical device such as gas setting on a gas cooker, or a volume setting on an audio amplifier. A conventional control knob is usually attached to a shaft extending from the mechanical/electrical device. The shaft can be rotated by the control knob, and the rotation is translated to the desired control setting. The control knob and the device may have visual indicators that provide feedback on the current and/or available settings.

In some scenarios, it may be desirable to have a removable control knob. This can be for many reasons including repair or mere aesthetics. Removing the control knob itself may be undesirable since a shaft extending from the mechanical/electrical device would be exposed. Alternatively, if the shaft is connected to the control knob, removing the control knob would expose an opening in the mechanical/electrical device for the shaft. Removal of the control knob is thus constrained by the manner in which it interacts with the mechanical/electrical device.

Control knobs that avoid a shaft connection between the control knob and an electrical device have been proposed. For example, it is known to have a removable control knob for an electric cooker with an induction hob. Typically a removable control knob is placed on a specific location on the electric cooker. The removable control knob has a magnet within that helps maintain contact and alignment with the cooker, whilst still permitting rotation of the control knob. A rotation of the control knob is detected by a sensor array within the cooker. For example, each hall sensor of a circular arrangement of hall sensors may be activated in sequence as the magnet rotates above. This sequence can be translated into a desired setting such as a temperature of the inductive hob. However, the rotational resolution provided is low, and it can be a challenge to merely obtain eight discrete rotation positions per a complete revolution of the control knob. In particular, although the number of sensors within the cooker can be increased, the sensors will only be activated as desired if the rotation of the removable control knob occurs about an imaginary axis corresponding to a centre of the sensor array. In practice, the removable control knob will move laterally about the imaginary axis when the removable controllable knob is rotated. In other words, it is difficult to maintain axial alignment of the removable control knob and the sensor array. Thus, there is a trade off between rotating the knob and precise control over the temperature set. For example, a full revolution may allow the user to move from 0 to 240°C in 30°C increments or three full revolutions may allow the user to move from 0 to 240°C in 10°C increments.

Additionally, the control knob can be tilted so that an edge contacts the cooker. The point of contact can activate a desired hob on the cooker. This may be achieved by a discrete hall sensor at a respective point of contact. In practice, a user may inadvertently activate/deactivate another hob by accidently tilting the control knob during a rotation.

Therefore it is desirable to have a removable control device that provides higher resolution rotation per revolution, i.e. more discrete intervals per revolution. It would also be desirable to be able to provide a reliable secondary, non-rotational/tilting, input using the removable control device. Whilst such a removable control device could be used with an electric cooker with an induction hob, in principle, it would have a wider range of applications. For example, such a removable control device could interact with a display, e.g. a touch screen device, for precision input. Alternatively, a volume control could be provided for a mixing console.

Summary

In a first aspect of the invention, there is provided a removable control device for controlling an electrical device, wherein the control device comprises: a first part configured to contact an electrical device; a second part configured to co-operate with the first part to enable relative rotation therewith; a rotary encoder; and communication circuitry; wherein a relative rotation between the first part and second part causes the rotary encoder to generate a first output signal indicative of the relative rotation; and wherein the first output signal is communicated to the electrical device via the communication circuitry. A high resolution rotational input can be communicated to an electrical device.

Preferably, the first output signal is indicative of a gradation of the relative rotation. A precise angular rotation can thus be communicated to the electrical device. Preferably the communication circuitry comprises wireless communication circuitry. This allows the removable control device to communicate the first output signal in the absence of direct electrical contact with the electrical device. Simply placing the removable control device on the electrical device will enable the first output signal to be communicated to the electrical device.

Preferably, the rotary encoder is mounted or arranged on or within the first part and the second part rotates an input of the rotary encoder, or the rotary encoder is mounted or arranged on or within the second part and the first part rotates an input of the rotary encoder. This allows relative rotation between the first and second parts to be encoded at the rotary encoder.

Preferably, the rotary encoder input comprises a shaft, and the rotary encoder converts a rotation of the shaft to the first output signal. This generates the first output signal that corresponds to the relative rotation of the first and second parts.

Preferably, the first part and/or the second part comprises a switch that generates a second output signal that is transmitted to the electrical device via the wireless communication circuitry. The removable control device thus has two outputs that can be communicated to control the electrical device. Optionally, the switch comprises a button comprising a shaft of the rotary encoder to generate the second output signal. The rotary encoder can generate both the first and second output signals.

Preferably, the first part comprises a gripping surface to contact an electrical device, wherein the gripping surface optionally comprises rubber or neoprene. This helps maintain a desired placement/alignment of the removable control device.

Preferably, the first part comprises a magnet to maintain contact and/or alignment between the first part and an electrical device; and/or a magnetic/electrical connector to maintain contact and/or alignment between the first part and an electrical device. This helps maintain a desired placement/alignment/contact of the removable control device to ensure reliable use thereof. It also avoids the need to have a detent/recess in the electrical device for contact/alignment purposes, the otherwise increase manufacturing complexity of the electrical device.

Preferably, the wireless communication circuitry is passive and configured to receive power from a coil in the electrical device upon contact of the first part and electrical device. The removable control device can be implemented as a passive device. Preferably, the removable control device of any preceding claim, wherein the first part and second part both have a cylindrical shape and share a common axis. This helps effect relative rotation between the first and second parts.

Preferably, the first part and the second part comprise a snap-fit connection. This allows the first and second parts to be readily connected or separated for repairs and/or replacement of certain components.

Preferably, the snap-fit connection comprises a plurality of legs extending from the first part, wherein each leg comprises a protruding edge that engages with a recess area in the second part to enable relative rotation between the first and second parts. Alternatively, the snap-fit connection comprises a plurality of legs extending from the second part, wherein each leg comprises a protruding edge that engages with a recess area in the first part to enable relative rotation between the first and second parts. This serves as a means for both joining the first and second parts and enabling relative rotation between the first and second parts.

Preferably, the first and/or second parts comprises a display that provides visual feedback on at least one of: power being provided to the removable control device; the relative rotation; and positioning of the removable control device on the electrical device. Optionally, the display comprises LEDs arranged around the first and/or second parts. Additionally or alternatively, the removable control device is configured to provide physical feedback and/or audible feedback in response to the relative rotation. Preferably, the encoding device provides the physical feedback and/or audible feedback when a shaft of the encoding device is rotated. All of these feedback mechanisms are designed to assist the user in performing a technical task by providing a continued and/or guided human-machine interaction process. Preferably, the feedback means are specifically configured to guide a user when operating an inductive hob on an induction cooker.

Preferably, the encoding device and the wireless communication circuitry are housed on a printed circuit board, wherein the printed circuit board is mounted on the first part or the second part. This allows the removable control device to be easily repaired by changing out a faulty circuit module or the entire printed circuit board itself.

Preferably, the first output signal is used to control a temperature setting of the electrical device. This results in precise temperature control. Preferably, the second output signal is used to confirm a temperature setting of the electrical device, and/or select a menu on the electrical device. This allows a setting controlled by the first output signal to be unlocked/locked, and/or access menus in the electrical device.

In a second aspect of the invention, there is provided a system comprising: an electrical device comprising a heating element; and the removable control device of the first aspect; wherein the first output signal is used to control a temperature setting of the heating element when the first part is in contact with a location on the electrical device; and optionally wherein when the first part contacts the location, the electrical device transitions to a power on state; and/or optionally wherein the system is configured such that when the first part is not in contact with the location, the electrical device transitions to a standby state, and/or prompt a user to select a mode of operation of the electrical device. The system has a high resolution rotational removable input control device.

In a third aspect of the invention, there is provided a cooking device comprising: an induction hob; and the removable control device of the first aspect; wherein the first output signal is used to control a temperature setting of the induction hob when the first part is in contact with a location on the cooking device; and optionally wherein when the first part contacts the location, the cooking device transitions to a power on state; and/or optionally wherein the cooking device is configured such that when the first part is not in contact with the location, the cooking device transitions to a standby state, and/or prompt a user to select a mode of operation of the cooking device. The cooking device has a high resolution rotational removable input control device.

In a fourth aspect of the invention, there is provided a method of assembling a removable control device for an electrical device, the method comprising: placing a first part into co-operation with a second part to enable relative rotation therewith, wherein the first part is configured to contact an electrical device; wherein the first and/or second part comprises: a rotary encoder; and communication circuitry; wherein the placing of the first part into co-operation with the second part permits a relative rotation between the first part and second part to cause the rotary encoder to generate a first output signal indicative of the relative rotation; and wherein the first output signal can be communicated to the electrical device via the communication circuitry. Assembling a removable control device in this way allows a high resolution rotational input to be communicated to an electrical device.

In a fifth aspect of the invention, there is provide a kit for assembling a removable control device for an electrical device, the kit comprising: a first part configured to contact an electrical device; a second part configured to co-operate with the first part to enable relative rotation therewith; a rotary encoder; and communication circuitry; wherein the first part is configured to co-operate with the second part such that a relative rotation between the first part and second part cause the rotary encoder to generate a first output signal indicative of the relative rotation, wherein the first output signal can be communicated to the electrical device via the communication circuitry. The kit can be used to assembling a removable control device that allows a high resolution rotational input to be communicated to an electrical device.

Brief Description of Drawings

Figures 1A-C show 3D and 2D views of a removable control device.

Figures 2A-C, show a 2D view, a cross sectional view, and a 2D side view of the removable control device.

Figure 3 shows a 3D view of a first part of the removable control device.

Figure 4A and 4B show two implementations of a communications circuit of the removable control device.

Figure 5 shows a system diagram comprising the removable control device and an electrical device.

Figure 6 shows the removable control device on a cooking device. Description

With reference to the drawings, and as best shown in figures 1A-C, and 2A, there is shown a removable control device 100 for controlling an electrical device. The removable control device comprises a first part 110 configured to contact an electrical device. The first part is generally cylindrically shaped with a hollow core. Of course, the first part can adopt a polygon shape with a hollow core, where the polygon has any number of sides, such as a pentagon, or a hexagon, or an octagon. The hollow core allows certain components to be housed within. The first part can be made from any suitable plastics and/or metal material (preferably non-ferrous such as aluminium).

A bottom of the first part may include a gripping surface 120. Such a gripping surface can be made from any material that increases friction between the removable control device and the electrical device, such as rubber or neoprene for example. The gripping surface helps maintain the position of the removable control device when the removable control device is being rotated.

A means for aligning the first part with a given location on the electrical device, and maintaining contact between the first part and the second part, may be used. For example, the base or the bottom of the first part may house a magnet 130 that interacts with a magnet within the electrical device. Alternatively or additionally, the first part may have a magnetic/electrical connector that interacts with a corresponding magnetic/electrical connector on the electrical device. Such a magnetic/electrical connector can maintain alignment and/or contact between the first part and the electrical device, and simultaneously provide electrical communication between the first part and the electrical device.

The removable control device also has a second part 140 that is configured to co-operate with the first part to enable relative rotation therewith. The second part is generally cylindrically shaped with a hollow core. Of course, the second part can adopt a polygon shape with a hollow core, where the polygon has any number of sides, such as a pentagon, or a hexagon, or an octagon etc. The hollow core allows certain components to be housed within. The second part can be made from any suitable plastics and/or metal material. In the example shown in figures 1A-C, the first and second parts both have a cylindrical shape and share a common axis. In principle, the first and second parts can adopt any shape and not necessarily the same shape provided they can co-operate with each other as described below. Although the terms first and second are used above, they are merely nominal terms that do not otherwise have a limiting effect.

In the example shown in figures 2B and 2C, the first part and the second part comprise a snap-fit connection where a plurality of legs 150 extend from the first part, each leg having a protruding edge 160 that engages with a recess area 170 in the second part to enable relative rotation between the first and second parts. Alternatively, a plurality of legs extend from the second part, each leg having a protruding edge that engages with a recess area in the first part to enable relative rotation between the first and second parts. Although a snap-fit connection is shown, the skilled person will appreciate that various co-operation means are available to enable relative rotation, such as a bushing, or a bearing etc.

As shown in figures 2B, 2C, and 3, the removable control device includes a rotary encoder 180 to encode the relative rotation. The rotary encoder to encode the relative rotation can include a discrete off-the-shelf rotary encoder, such as the PEC11S Series by Bourns®. Off-the-shelf rotary encoders can be mechanical based, optical based, magnetic based, capacitive based etc., all of which can be used with the removable control device. Alternatively, a custom solution can be used where certain electronic components are arranged in the removable control device to encode the relative rotation. One such custom solution includes building an optical rotary encoder using the first and second parts. For example, the first part could house a circular interruption disc, a light source, and a photodetector. The circular interruption disc could have a discreet pattern of concentric slots through which the light from the light source passes for detection by a photodetector. The second part would then be connected to the circular interruption disc in a way that allows it to rotate the circular disc. The periodic interruption of the light from the light source as it moves across the pattern of concentric slots would be detected by the photo diode.

With reference to figure 5, irrespective of how the rotary encoder is implemented, at a general level, the rotary encoder has an input 215, where rotation of the input 510 is reflected at a first output signal 540 at terminals of the rotary encoder 530. The first and second parts can interact with the encoder to translate relative rotation between the first and second parts to the input of the rotary encoder. The relative rotation of the first and second parts is reflected in the first output signal of the rotary encoder. Compared to existing removable control knobs, the rotational resolution is much higher and is only constrained by the angular resolution of the rotary encoder. In some implementations, at least 30 gradations of 12° of rotation per revolution (i.e. when the second part rotates 360° relative to the first part) can be achieved. Alternative implementations include 10 gradations of 36° of rotation per revolution, or 20 gradations of 18° of rotation per revolution, or 60 gradations of 6° of rotation per revolution.

The first output signal can be an analogue signal such as a voltage or current, or a digital signal. An analogue signal can increase or decrease in correspondence to the relative rotation. An increase may correspond to clockwise rotation and a decrease may correspond to an anticlockwise rotation, and vice versa. The extent of the increase or decrease corresponds to a gradation of rotation. A constant analogue signal is indicative of zero relative rotation (i.e. there is no change in the relative rotation of the first part and the second part). An analogue implementation may use a potentiometer where a rotation of a potentiometer input varies a resistance to produce a varying voltage and/or current at terminals of the potentiometer. A digital signal may comprise an n bit binary digital signal. For example, as the input rotates, a two-bit binary signal produces a binary number sequence of 01, 00, 10, 11, 01, 00, 10, 11 etc. as the input rotates clockwise, and a binary number sequence of 11, 10, 00, 01, 11, 10, 00, 01 as the input rotates anti-clockwise. Each change in a binary number corresponds to a gradation of relative rotation. A constant binary number is indicative of zero relative rotation (i.e. there is no change in the relative rotation of the first part and the second part).

As shown in figures 2B, 2C, and 3, the rotary encoder may be mounted or arranged on or within the first part, and the second part interacts with the input of the rotary encoder. Alternatively, the rotary encoder may be mounted or arranged on or within the second part, and the first part interacts with the input of the rotary encoder. In either case, a gradation and/or a direction of relative rotation between the first and second parts is reflected in the first output signal of the rotary encoder. In the example shown in figures 2B, 2C, and 3, the second part has an internal collar/recess 200 to which a plastic ring 190 is attached. The plastic ring has internal teeth 195 that mesh with external teeth 196 on the input shaft 215 of an off-the-shelf rotary encoder. The plastic ring may be held in place in the collar/recess by glue or a friction fit. Both the collar/recess and the rotary encoder are aligned along the common axis. The rotary encoder itself is attached to a base 210 of the first part. This means that when the second part “snaps” on to the first part via the snap-fit connection, the input of the rotary encoder automatically interacts with the second part via the teeth on both the collar and input shaft meshing. Having a second part that co-operates with the first part means the removable control device lends itself to repair and replacement of certain components, such as the rotary encoder, or even the second part itself. The skilled person will appreciate that other arrangements are possible. For example, the inside circumference of the second part may have teeth (e.g. a ring gear) that engages a gear on the input shaft of the rotary encoder.

The rotary encoder can communicate the first output signal to the electronic device via communication circuitry 560. The communication circuitry and the rotary encoder may share a common printed circuit board integrated with the base. As explained below, the communication circuitry 220 can take several forms.

As shown in figure 4A, one implementation 400 of the communication circuitry 220, 560 comprises a first inductive coil 410 that communicates with a second inductive coil 420 in the electrical device. The first inductive coil may be printed on the common printed circuit board. The first inductive coil receives power via the second coil when the first and second inductive coils are in close proximity (i.e. when the first part is in contact with a location on the electrical device). The communication circuitry has a power module 430 that receives power from the electrical device via the first and second inductive coils. The communication circuitry has an interface 440 to the terminals of the rotary encoder to provide power thereto, and receive the first output signal therefrom. The communication circuitry is configured to use modulator/demodulator 450 to modulate the first output signal and communicate the first output signal wirelessly from the first induction coil to the second induction coil, and thus communicate a relative rotation of the first and second parts to circuity 460 of the electrical device. With this arrangement, simply placing the removable control device in a way that allows the first and second inductive coils to couple with each other will permit a relative rotation of the control device to be communicated to the electrical device.

In an alternative example shown in figure 4B, one implementation 480 of the communication circuitry 220, 560 may simply provide an electrical path to each of the terminals of the rotary encoder 470, for example via a flat flexible cable. The paths allow power to be received at the rotary encoder from the electrical device, for example via the magnetic/electric connector described above. The paths provide the first output signal of the rotary encoder to corresponding circuitry 490 in the electrical device, again via the magnetic/electric connector described above. With this arrangement, simply placing the removable control device in a way that allows the magnetic/electrical contacts on both the first part and the electrical device to mate will permit a relative rotation of the control device to be communicated to the electrical device.

In addition to communicating a relative rotation of first and second parts, a second output signal 550 may be provided from the removable control device. The second part itself can serve as “button” that is capable of movement along its axis. In the implementation shown, the shaft of the rotary encoder 215, 520, 530 can also be pressed along its axis to provide a switching action and provide a second output signal via its terminals. In this implementation, pressing the second part activates the switching action in the shaft of the rotary encoder. Alternatively, the second part itself may have an integrated switch 520 that provides the second output signal directly. The second output signal can indicate the state of the switch, e.g. “on” or “off”. The switch may be a latching switch or a momentary non-latching switch. The second output signal may be analogue or digital. The communications circuit 560 provides the second output signal to circuitry 570 in the electrical device in the same manner described above in respect of the first output signal. Although the switch is the mechanical “button” type, the skilled person would appreciate that other switch types could be used such as capacitive or resistive touch switches. How the electrical device may use the second output signal is explained below.

The removable control device may use various means to provide feedback to the user as they operate the removable control device. As explained below, such feedback means are specifically configured to guide a user when operating an electrical device, such as controlling an inductive hob on an induction cooker. For example, the rotary encoder may have detents that provide physical feedback when the input of the rotary encoder is rotated. The detents may also provide audible feedback. Using detents to provide physical/audible feedback during rotation is well known to the skilled person, e.g. a scroll wheel in a computer mouse. Implementing detents within the removable control device to provide physical/audible feedback is straightforward for the skilled person.

Additionally or alternatively, the removable control device may comprise an LED 240 (as shown in figures 2B) to provide visual feedback. The LED is positioned so that its light is visible at a gap 185 between the first and second parts. This can be achieved by placing the LED on the side of the common PCB board so that it side fires towards the gap. The electrical device can control the LED via the communication circuitry. In one implementation, the LED can be activated to indicate that the removable control device is receiving power from the electrical device. In another implementation, the LED may be a multi-colour LED that changes colour in accordance with the relative rotation and/or the state of the switch. For example, the LED may be dark blue when the removable control device is first placed on the electrical device and transitions to dark red during a full revolution of the second part relative to the first part, i.e. a temperature scale. Similarly, the LED may flash either once or for a period of time, e.g. 2 seconds, once the state of the switch changes. As an alternative or addition to the LED, an LED array may also be arranged around the first and/or second parts. For example, a series of LEDs can be positioned so that they are visible around the gap between the first and second parts. Each LED of the LED array can light in sequence as the second part rotates with respect to the second part. The number of LEDs that are lit corresponds to the relative rotation of the second part with respect to the first part. In an implementation where the LED array is used instead of a single LED, the first LED of the LED array may light up to indicate that the removable control device is receiving power from the electrical device. Similarly, all of the LEDs may flash either once or for a period of time, e.g. 2 seconds, once the state of the switch changes. Additionally or alternatively, the LED or LED array can indicates whether the removable control device has been placed in an optimum location on the electrical device. For example, when the removable control device is placed in the optimum location, the LED or LED array may be green for 2 seconds. If the removable control device moves away from the optimum location, the LED or LED array will continuously flash red until the removable control device returns to the optimal location. A hall sensor may be used in the electrical device to determine that the removable control device is or is not in the optimal location.

As shown in figure 5, the removable control device 500 described above can be used with any suitably configured electrical device 590. Such an electrical device will have a location on which the removable control device is placed. The location may have a recess area or marker to help identify the location and assist with the placement of the removable control device. A magnet and/or magnetic/electric connector may be located within or on the cooker to interact with the corresponding magnet and/or magnetic/electric connector on the first part. Assuming the communication circuitry 560 uses wireless communication as described above, the electrical device has an induction coil to couple with the induction coil in the removable contact device.

The electrical device has circuitry 570 that can receive the first 540 and/or second 550 output signal via communications circuit 560. The first output signal may be processed by the electrical device to control a first setting 580, e.g. temperature or volume in accordance with the relative rotation between the first and second parts. A gradation of a rotation indicated by the first output signal can effect a given increment/decrement requirement of the first setting. The second output signal may be processed by the electrical device to access and control a menu on the electrical device. Activating the switch cycles between the menu options on the electrical device. Upon release of the switch the desired menu option is selected. Alternatively, the second output signal may be processed by the electrical device to lock the current first setting. For example, if the second output signal indicates a change in state of the switch 520, the current setting will not change in response to the first output signal. Conversely, after the electrical device has locked the current first setting, if the second output signal indicates a subsequent change in state of the switch, the current setting will be unlocked and change in response to the first output signal.

Additionally, the electrical device may transition from a standby state to a power on state when the first part contacts a location on the electrical device. Thereafter, the electrical device may transition from a power on state to a standby state when the first part does not contact the location on the electrical device (i.e. the removable control device is subsequently removed). Alternatively, when the removable control device is removed, the electrical device may prompt the user to select a mode of operation for the electrical device. For example, if a timed procedure on the electronic device was taking place when the removable control device is removed, the timed procedure can be paused, or stopped and have the electrical device return to the standby state, or locked until completion. Alternatively, removing the removable control device may automatically trigger a timer for the standby mode. Assuming the removable control device is placed back on the location before the timer reaches a pre-defined time, the electrical device will transition back to the power-on mode. Assuming the removable control device is not placed back on the location and the timer has reached the pre-determined time, the electrical device will transition from the standby mode to a power-off mode.

One specific implementation of the electrical device described above is an electrical cooker with an induction hob (also known as an induction cooker). With reference to figure 6, assuming the induction cooker 600 is in standby mode, placement of the removable control device 100 on a location 250 of the cooker will transition the cooker to a power on mode. Visual feedback of the transition to the power on mode may be provided as described above. Thereafter a relative rotation between the first and second parts will change a temperature setting of the induction hob 260. As mentioned above, a gradation of a rotation indicated by the first output signal can effect a given increment/decrement requirement of the first setting. For example, assuming the first output signal can indicate 30 gradations of rotation per revolution, each gradation may correspond to a 5°C change in temperature, so one full revolution can go between 0°C and 150°C in 5°C increments. Physical/audible/visual feedback on the relative rotation may be provided as described above. Given the high rotational resolution, the user will have precise control over the temperature. The induction cooker may also have a display 270 that indicates the exact temperature. Once the desired temperature has been set, the user can change the state of the switch to lock the temperature setting, or access menus shown on display 270. Removing the removable control device will either present the user with options for selecting a cooking mode of operation (e.g. pause, stop, lock as described above), or transition the induction cooker to a stand-by mode, and after a predefined time, a power- off mode.

A method of assembling the removable control device includes placing the first part into co-operation with a second part to enable relative rotation therewith using the means described above. The first and/or second part includes the rotary encoder and communication circuitry as described above. The placing of the first part into co-operation with the second part permits a relative rotation between the first part and second part to cause the rotary encoder to generate a first output signal indicative of the relative rotation as described above such that the first output signal can be communicated to the electrical device via the communication circuitry.

The removable control device may be assembled as described above using the components from a kit. The kit includes the first part, the second part, the rotary encoder, and the communication circuitry described above. As descried above, the first part is configured to co-operate with the second part such that a relative rotation between the first part and second part cause the rotary encoder to generate a first output signal indicative of the relative rotation, wherein the first output signal can be communicated to the electrical device via the communication circuitry.

It will be appreciated that the above disclosure provides specific examples of certain implementations of the invention, and that modifications can be made within the scope of the appendant claims.

Claims

1. A removable control device for controlling an electrical device, wherein the control device comprises: a first part configured to contact an electrical device; a second part configured to co-operate with the first part to enable relative rotation therewith; a rotary encoder; and communication circuitry; wherein a relative rotation between the first part and second part causes the rotary encoder to generate a first output signal indicative of the relative rotation; and wherein the first output signal is communicated to the electrical device via the communication circuitry.

2. The removable control device according to any preceding claim wherein the first output signal is indicative of a gradation of the relative rotation.

3. The removable control device according to any preceding claim, wherein the communication circuitry comprises wireless communication circuitry.

4. The removable control device of any preceding claim, wherein the rotary encoder is mounted or arranged on or within the first part and the second part rotates an input of the rotary encoder, or the rotary encoder is mounted or arranged on or within the second part and the first part rotates an input of the rotary encoder.

5. The removable control device of claim 4, wherein the rotary encoder input comprises a shaft, and the rotary encoder converts a rotation of the shaft to the first output signal.

6. The removable control device of any preceding claim, wherein the first part and/or the second part comprises a switch that generates a second output signal that is transmitted to the electrical device via the wireless communication circuitry.

7. The removable control device of claim 6 when dependent on claim 5, wherein the switch comprises a button comprising the shaft, and the rotary encoder generates the second output signal.

8. The removable control device of any preceding claim, wherein the first part comprises a gripping surface to contact an electrical device, wherein the gripping surface optionally comprises rubber or neoprene.

9. The removable control device of any preceding claim, wherein the first part comprises: a magnet to maintain contact and/or alignment between the first part and an electrical device; and/or a magnetic/electrical connector to maintain contact and/or alignment between the first part and an electrical device.

10. The removable control device of any one of claims 3 to 9, wherein the wireless communication circuitry is passive and configured to receive power from a coil in the electrical device upon contact between the first part and electrical device.

11. The removable control device of any preceding claim, wherein the first part and second part both have a cylindrical shape and share a common axis.

12. The removable control device of any preceding claim, wherein the first part and the second part comprise a snap-fit connection.

13. The removable control device of claim 12, wherein the snap-fit connection comprises a plurality of legs extending from the first part, wherein each leg comprises a protruding edge that engages with a recess area in the second part to enable relative rotation between the first and second parts.

14. The removable control device of claim 12, wherein the snap-fit connection comprises a plurality of legs extending from the second part, wherein each leg comprises a protruding edge that engages with a recess area in the first part to enable relative rotation between the first and second parts.

15. The removable control device of any preceding claim, wherein the first and/or second parts comprises a display that provides visual feedback on at least one of: power being provided to the removable control device; the relative rotation; and positioning of the removable control device on the electrical device.

16. The removable control device of claim 15, wherein the display comprises LEDs arranged around the first and/or second parts.

17. The removable control device of any preceding claim, wherein the removable control device is configured to provide physical feedback and/or audible feedback in response to the relative rotation.

18. The removable control device of claim 17 when dependent on claim 5, wherein the encoding device provides the physical feedback and/or audible feedback when the shaft is rotated.

19. The removable control device of any preceding claim, wherein the encoding device and the wireless communication circuitry are housed on a printed circuit board, wherein the printed circuit board is mounted on the first part or the second part.

20. The removable control device of any preceding claim, wherein the first output signal is used to control a temperature setting of the electrical device.

21. The removable control device of any one of claims 6 to 20, wherein the second output signal is used to confirm a temperature setting of the electrical device, and/or select a menu on the electrical device.

22. A system comprising: an electrical device comprising a heating element; and the removable control device of any preceding claim; wherein the first output signal is used to control a temperature setting of the heating element when the first part is in contact with a location on the electrical device; and optionally wherein the system is configured such that when the first part contacts the location, the electrical device transitions to a power on state; and/or optionally wherein the system is configured such that when the first part is not in contact with the location, the electrical device transitions from to a standby state, and/or prompt a user to select a mode of operation of the electrical device.

23. A cooking device comprising: an induction hob; and the removable control device of any preceding claim; wherein the first output signal is used to control a temperature setting of the induction hob when the first part is in contact with a location on the cooking device; and optionally wherein the cooking device is configured such that when the first part contacts the location, the cooking device transitions to a power on state; and/or optionally wherein the cooking device is configured such that when the first part is not in contact with the location, the cooking device transitions to a standby state, and/or prompt a user to select a mode of operation of the cooking device.

24. A method of assembling a removable control device for an electrical device, the method comprising: placing a first part into co-operation with a second part to enable relative rotation therewith, wherein the first part is configured to contact an electrical device; wherein the first and/or second part comprises: a rotary encoder; and communication circuitry; wherein the placing of the first part into co-operation with the second part permits a relative rotation between the first part and second part to cause the rotary encoder to generate a first output signal indicative of the relative rotation; and wherein the first output signal can be communicated to the electrical device via the communication circuitry.

25. A kit for assembling a removable control device for an electrical device, the kit comprising: a first part configured to contact an electrical device; a second part configured to co-operate with the first part to enable relative rotation therewith; a rotary encoder; and communication circuitry; wherein the first part is configured to co-operate with the second part such that a relative rotation between the first part and second part cause the rotary encoder to generate a first output signal indicative of the relative rotation, wherein the first output signal can be communicated to the electrical device via the communication circuitry.