Cleaning appliance

Abstract

The present invention relates to a cleaning appliance, and in particular, although not exclusively, to a cleaning appliance comprising a body and a cleaner head, the cleaning appliance comprising an improved system for controlling and communicating with the cleaner head. In particular, the present invention provides a cleaning appliance in which a body is configured to supply power to a cleaner head via a plurality of conductors, and in which: the body comprises a first controller configured to modulate the supply of power to the cleaner head, the cleaner head comprises a second controller configured to detect a modulation of the supply of power, and, in response to the modulation, control the power to the cleaner head. And means for controlling the cleaner head.

Description

Technical Field

[0001] The present invention relates to a cleaning appliance, and in particular, although not exclusively, to a cleaning appliance including a main body and a cleaning head, the cleaning appliance including an improved system for controlling and / or communicating with the cleaning head. Background Art

[0002] Certain types of vacuum cleaner appliances include a main body that can be connected to a cleaning head. For example, they can be "stick vacuum" type vacuum cleaners, including a hand-held vacuum cleaner attached to an elongated rigid rod and fluidly connected to a cleaning head disposed at the end of the rod. In such vacuum cleaners, the cleaning head can be directly connected to the main body, or in some arrangements, can be connected to the main body via a rigid rod. Examples of such vacuum cleaners can be found in US8347455B2 or US9301665B2.

[0003] In some examples of such vacuum cleaners, power can be delivered from the main body to the cleaning head, such as powering a motor in the cleaning head. However, it is difficult to control additional components within the cleaning head. In particular, it is difficult and costly to implement a communication channel between the main body and the cleaning head, which can be used to control any additional components.

[0004] In view of the above considerations, the present invention has been devised. Summary of the Invention

[0005] According to a first aspect of the present invention, there is provided a cleaning appliance, such as a vacuum cleaner, including a main body and a cleaning head, wherein the main body is configured to supply power to the cleaning head via a plurality of conductors, wherein: the main body includes a first controller configured to modulate the power supply to the cleaning head, and the cleaning head includes a second controller configured to detect the modulation of the power supply and, in response to the modulation, control components of the cleaning head. By arranging in this way, components of the cleaning head can be controlled from the main body of the cleaning appliance without the complexity and cost associated with providing an additional communication channel between the main body and the cleaning head. Instead, the control of components within the cleaning head is performed based on the modulation of an electrical signal (e.g., the power delivered to a motor within the cleaning head) between the main body and the cleaning head. That is, the control of components within the cleaning head is achieved by utilizing the plurality of conductors for supplying power to provide a communication function that is parallel or concurrent with the power supply, and the communication is based on modulating the power supply.

[0006] In an embodiment, in addition to the components, the cleaner head may include a motor, wherein the body is configured to supply power to the motor and control the power supplied to the motor, and a first controller may be configured to modulate the power supply to the motor, and the modulation may be detected by a second controller for controlling components separated from the motor. For example, a motor may be provided to drive a brush bar or the like located at the cleaner head. In such an arrangement, the modulation of the power supply to the motor may be configured such that the operation of the motor is not unduly affected, as explained herein.

[0007] Optionally, the plurality of conductors may include three conductors. Implementing the plurality of conductors as three conductors may provide a relatively simple engineering arrangement, for example, in the case where the three conductors pass through the rod of a "stick vacuum" type vacuum cleaner, and may allow a relatively inexpensive and simple three-pin electrical connection between the body and the cleaner head. However, it should be understood that in some embodiments, there may be only two conductors. For example, the conductors may be wires.

[0008] The plurality of conductors may be at least partially included in the rod of the cleaning appliance that connects the body to the cleaner head.

[0009] Optionally, the body may include a three-phase inverter for driving the motor in the cleaner head. By arranging in this way, the cleaning appliance can be more ergonomic because the weight of the three-phase inverter for driving the BLDC motor in the cleaner head is set in the body, rather than in the cleaner head itself as in known arrangements. In particular, for a "stick vacuum" type vacuum cleaner, the body is held by the user (e.g., with a handle), and the cleaner head is at a distance from the body. Therefore, by concentrating more weight on the body, the cleaning appliance is easier to hold and operate. In addition, by providing the three-phase inverter in the body, the cleaner head itself can be simpler and have a lower manufacturing cost. In particular, in such an arrangement, it is difficult and expensive to implement an additional communication channel between the body and the cleaner head. Therefore, it may be particularly advantageous to use the modulation of the power supply as a channel for controlling the components in the cleaner head.

[0010] Optionally, the second controller may include a hardware circuit (e.g., including an operational amplifier), or a microcontroller (e.g., the MSP430 microcontroller from Texas Instruments).

[0011] Modulating the power supply may include or mean regulating or changing or altering the power supply. For example, modulation may include or mean regulating or changing or altering the power supply along any one or more of the plurality of conductors.

[0012] The modulation may be a temporary modulation, such as applying modulation for a predetermined period of time.

[0013] Optionally, the first controller may be configured to modulate the power supply by pausing at least one of the power supplies; adjust the pulse width modulation (PWM) frequency of the power supply; and / or adjust the PWM pulse width of the power supply. These may be referred to herein as different modulation types. Modulating the power supply to the cleaner head preferably does not adversely interfere with the control or operation of the motor and may be selected (e.g., the type of modulation) and configured (e.g., the duration of the modulation) based on hardware limitations (e.g., the maximum transfer rate achievable by the first controller and / or the second controller, the motor configuration). For example, pausing the power supply may include turning off the power supply for a short period of time (a predetermined period of time) and then turning the power supply back on. In some examples, pausing the power supply may include pausing the power supply along one or more of the plurality of conductors. The short period of time (or predetermined period of time) may be short enough not to interfere with proper motor control and long enough to be sensed by the second controller. Such a period of time may be less than 10 ms, such as 3 ms or 4 ms. In particular, pausing the power supply in this way for a short period of time may provide more reliable control of the motor and reduce the risk of undesired side effects, such as the user hearing the modulation in the power supply (i.e., the user senses that the power supply to the motor within the cleaner head has been paused). Adjusting the PWM frequency may include changing the PWM frequency from a nominal operating frequency (at which the controller and the motor may operate most of the time) to another frequency within the motor hardware and control performance limitations (which may be higher or lower than the nominal operating frequency) and which also does not cause harmful performance of the motor. For example, the first frequency (nominal operating frequency) may be a low frequency (e.g., 30 KHz) and the second frequency may be a high frequency (e.g., 60 KHz). Modulating the power signal in these ways may be advantageous because of the high difference between the power signal states (e.g., the off state when the power supply is paused versus the on state; or the first frequency state (nominal operating frequency) versus the second frequency state of the PWM frequency change). In addition, such modulation does not overly affect the performance of the motor (e.g., a BLDC motor) in the cleaner head to which the power is supplied.

[0014] In embodiments where the first controller is configured to modulate the power supply by pausing the power supply (e.g., pausing the power supply along one or more of a plurality of conductors), the second controller may be configured to communicate with the first controller during the pause in the power supply (e.g., by generating or sending a communication signal). In this way, the cleaner head may be configured to communicate with the body. For example, the second controller may be configured to communicate with the first controller in at least one of the following ways: creating a short circuit between two of the plurality of conductors; and creating an open circuit on one of the plurality of conductors. In particular, this arrangement may work by encoding the communication signal as the back electromotive force (BEMF) from a motor in the cleaner head, where when the motor rotates (when it is active, or more particularly, in this case, when it rotates during a period when no power is being delivered to the motor), the motor generates BEMF as a generator. The BEMF is generally predictable, so a deviation from the expected pattern (i.e., the signal / message generated by the cleaner head) can be detected at the body.

[0015] In some embodiments, the first controller may be configured to effect a single modulation of the power supply to the cleaner head, and the second controller may be configured to control components in response to the single modulation.

[0016] In certain embodiments, the first controller may be configured to modulate the power supply to form a modulation sequence (specifically, where the modulation is a pause in the power supply and / or the modulation is an adjustment of the PWM frequency of the power supply as described above), and the second controller may be configured to detect the modulation sequence. In some examples, the modulation sequences may be spaced at regular time intervals, so the modulation sequence may thereby provide a "heartbeat" having a specific period and / or frequency that can be detected by the second controller. By providing in this way, the risk of mis-triggering control of cleaner head components can be reduced because the modulation sequence provides a lower risk of mis-identification compared to a single modulation.

[0017] In certain embodiments, the cleaner head may include a first component and a second component, and the second controller may be configured to control the first component in response to detecting that the modulation is a first modulation type (e.g., a pause in the power supply); and control the second component in response to detecting that the modulation is a second modulation type (e.g., an adjustment of the PWM frequency of the power supply). In this way, multiple components of the cleaner head may use the modulation of the power supply to the cleaner head as a communication channel to be controlled from the body, without the need to implement a dedicated communication channel between the body and the cleaner head, which would add additional cost and complexity to the cleaning appliance.

[0018] Optionally, the first controller may be configured to modulate the power supplied to the cleaner head to encode a message, and the second controller may be configured to decode the message from the modulation. By providing in this way, the power supply can also be used to provide one-way communication from the body to the cleaner head. For example, such one-way communication can be used to control more complex functions of the cleaner head, and / or independently control multiple additional components within the cleaner head.

[0019] Optionally, the components of the cleaner head may be any one or more of light-emitting diodes (LEDs); a laser; and / or a mechanical actuator. For example, the LED can illuminate dark areas being cleaned, the laser can illuminate dust and other large particles for better targeting of the area to be cleaned, and / or the mechanical actuator can be used to move a part of the cleaner head, such as a lid or closure over a hole in the cleaner head, which can be opened to allow large particles to be picked up by the cleaning appliance in use. For example, these components can obtain power from the power supply to the cleaner head (e.g., the motor within the cleaner head). In some embodiments, the cleaner head may include a parasitic power supply for this purpose.

[0020] According to a second aspect of the present invention, there is provided a method of operating a cleaning appliance, the cleaning appliance including a body and a cleaner head, wherein the body is configured to supply power to the cleaner head via a plurality of conductors; wherein the method includes: modulating the power supply to the cleaner head at the body; detecting the modulation of the power supply at the cleaner head; and controlling the components of the cleaner head in response to the detection. By arranging in this way, the components of the cleaner head can be controlled from the body of the cleaning appliance without the complexity and cost associated with providing an additional communication channel between the body and the cleaner head. Instead, the control of the components within the cleaner head is performed based on the modulation of the power signal (e.g., the power supplied to the motor within the cleaner head) between the body and the cleaner head. That is, the control of the components within the cleaner head is achieved by utilizing the plurality of conductors for supplying power to provide a communication function that is parallel or concurrent with the power supply, and the communication is based on modulating the power supply.

[0021] The cleaning appliance of the second aspect of the present invention may have any one or more features of the cleaning appliance of the first aspect of the present invention, unless incompatible with the features of the second aspect of the present invention.

[0022] In an embodiment, in addition to the components, the cleaner head may include a motor, wherein the body is configured to supply power to the motor, and the modulation of the power supply delivered to the motor can be detected by a second controller for controlling components separate from the motor. For example, a motor may be provided to drive a brush bar or the like located at the cleaner head. In such an arrangement, the modulation of the power supply to the motor can be configured such that the operation of the motor is not unduly affected, as explained herein.

[0023] Optionally, modulating the power supply to the cleaner head may include at least one of the following: pausing the power supply, such as pausing for a short period of time or a predetermined time, adjusting the pulse width modulation (PWM) frequency of the power supply; and / or adjusting the PWM pulse width of the power supply. These may be referred to herein as different modulation types. Modulating the power supply to the cleaner head preferably does not adversely interfere with the control or operation of the motor and may be selected (e.g., the type of modulation) and configured (e.g., the duration of modulation) based on hardware limitations (e.g., the maximum transfer rate achievable by the first controller and / or the second controller, the motor architecture). For example, pausing the power supply may include turning off the power supply for a short period of time and then turning the power supply back on. In some examples, pausing the power supply may include pausing the power supply along one or more of a plurality of conductors. The short period of time may be short enough not to interfere with motor control and long enough to be sensed by the second controller. Such a period of time may be less than 10 ms, such as 3 ms or 4 ms. In particular, pausing the power supply in this way for a short period of time may provide more reliable control of the motor and reduce the risk of undesirable side effects, such as the user hearing the modulation in the power supply (i.e., the user perceives that the power supply to the motor within the cleaner head has been paused). Adjusting the PWM frequency may include changing the PWM frequency from a nominal operating frequency (at which the controller and the motor can operate most of the time) to another frequency within the motor hardware and control performance limitations (which may be higher or lower than the nominal operating frequency), and which also does not result in harmful performance of the motor. For example, the first frequency (nominal operating frequency) may be a low frequency (e.g., 30 KHz) and the second frequency may be a high frequency (e.g., 60 KHz). Modulating the power signal in these ways may be advantageous because of the high difference between the power signal states (e.g., the off state when the power supply is paused versus the on state; or the first frequency state (nominal operating frequency) versus the second frequency state of the PWM frequency change). Additionally, such modulation does not overly affect the performance of the motor (e.g., a BLDC motor) in the cleaner head to which the power is supplied.

[0024] In embodiments where modulating the power supply to the cleaner head includes pausing the power supply (e.g., pausing the power supply along one or more of a plurality of conductors), the method may further include generating a signal from the cleaner head to the body during the power supply pause (e.g., sending a communication signal from the cleaner head to the body). In this way, the cleaner head can be configured to communicate with the body. For example, generating the signal may include creating at least one of a short circuit between two of the plurality of conductors; and creating an open circuit on one of the plurality of conductors. In particular, this arrangement may work by encoding the communication signal as the back electromotive force (BEMF) from a motor in the cleaner head, where the motor generates BEMF as a generator when it rotates (when it is active, or more particularly, in this case, when it rotates during a period when no power is delivered to the motor). The BEMF is generally predictable, so a deviation from the expected pattern (i.e., the signal / message generated by the cleaner head) can be detected at the body.

[0025] In some embodiments, modulating the power supply to the cleaner head may include forming a modulation sequence (in particular, where the modulation is a pause in the power supply and / or adjustment of the PWM frequency of the power supply as described above), such that the sequence is detectable at the cleaner head. In some examples, the modulation sequences may be spaced at regular time intervals, so the modulation sequences can thereby provide a "heartbeat" that can be detected by a second controller. By providing in this way, the risk of false triggering control of the cleaner head components can be reduced, as the modulation sequence provides a lower risk of false identification compared to a single modulation.

[0026] In some embodiments, the cleaner head may include a first component and a second component, and the method may further include determining, at the cleaner head, the type of modulation of the power supply; and, or: controlling the first component in response to determining that the modulation is a first modulation type (e.g., a pause in the power supply); or controlling the second component in response to determining that the modulation is a second modulation type (e.g., adjustment of the PWM frequency of the power supply). In this way, multiple components of the cleaner head can use the modulation of the power supply to the cleaner head as a communication channel for control from the body, without the need to implement a dedicated communication channel between the body and the cleaner head, which would add additional cost and complexity to the cleaning appliance.

[0027] Optionally, the modulation may include modulating the power supplied to the cleaner head to encode a message, and the method may further include decoding, at the cleaner head, the message from the modulation. In this way, the method of the second aspect of the present invention can also be used to provide one-way communication from the body to the cleaner head. For example, such a message can be used to control more complex functions of the cleaner head, and / or independently control many additional components within the cleaner head.

[0028] According to a third aspect of the present invention, there is provided a cleaning appliance according to the first aspect, further comprising a storage device storing instructions which, when executed, cause the first controller and the second controller to perform the method according to the second aspect of the present invention.

[0029] The present invention includes combinations of the described aspects and preferred features, unless such combinations are clearly impermissible or expressly avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Embodiments and experiments illustrating the principles of the present invention will now be discussed with reference to the accompanying drawings, in which:

[0031] Figure 1 is a perspective view showing a cleaning appliance according to an embodiment of the present invention;

[0032] Figure 2 is a schematic view of a cleaning appliance according to an embodiment of the present invention;

[0033] Figure 3 is a flowchart showing a first method according to an embodiment of the present invention;

[0034] Figure 4 is a flowchart showing a second method according to an embodiment of the present invention;

[0035] Figure 5 shows a first example of power modulation and associated control of components;

[0036] Figure 6 shows a second example of power modulation and associated control of components;

[0037] Figure 7 shows a third example of power modulation and associated control of components;

[0038] Figure 8 shows a fourth example of power modulation, associated control of components and two-way communication; and

[0039] FIG. 9 shows an example circuit diagram for implementing a communication signal from the cleaner head to the body. DETAILED DESCRIPTION

[0040] Aspects and embodiments of the present invention will now be discussed with reference to the accompanying drawings. Other aspects and embodiments will be apparent to those skilled in the art. All documents mentioned herein are incorporated herein by reference.

[0041] Figure 1A perspective view of a cleaning appliance according to an embodiment of the present invention is shown. In particular, the cleaning appliance is a vacuum cleaner 2. The vacuum cleaner 2 of this embodiment is a "stick vacuum" type vacuum cleaner. That is, it has a cleaner head 4, and the cleaner head 4 can be connected to the main body 6 through a generally tubular elongated rod 8. The cleaner head 4 can also be directly connected to the main body 6 to convert the vacuum cleaner 2 into a handheld vacuum cleaner.

[0042] The main body 6 includes a dust separator 10, which is a cyclone separator in this case. The cyclone separator has a first cyclone stage 12 including a single cyclone, and a second cyclone stage 14 including a plurality of cyclones 16 arranged in parallel. The main body 6 also has a removable filter assembly 18, and the filter assembly 18 is provided with a vent 20 through which air can be discharged from the vacuum cleaner 2.

[0043] In this case, the main body 6 of the vacuum cleaner 2 has a handle-type handle 22, and the handle is positioned to be held by the user. At the upper end of the handle-type handle 22 is an on / off switch (not visible) in the form of a trigger, and the switch must be held (i.e., "pulled") to keep the vacuum cleaner on. Once the user releases the trigger, the vacuum cleaner is turned off. The battery pack 26 is located below the lower end of the handle-type handle 22, and the battery pack includes a plurality of rechargeable batteries (not visible). A controller in the form of a PCB (not visible) and a vacuum motor including a fan driven by a motor (not visible) are provided in the main body 6 behind the dust separator 10.

[0044] It should be understood that many different cleaner heads can be directly or connected to the main body 6 through the rod 8. Each cleaner head can include different components (e.g., motors, lights), and some of them may require power supply and control from the main body. The vacuum cleaner 2 is thus configured to allow control of the components of the cleaner head 4 based on modulation of the power signal between the main body 6 and the cleaner head 4, as described below. Specifically, as described below, the main body 6 is configured to supply power to a motor (e.g., a motor for driving a brush bar, etc.) inside the cleaner head 4, and the modulation of the power supply to the motor can be used to control another component of the cleaner head (i.e., a component other than the motor).

[0045] Figure 2 A schematic diagram of a cleaning appliance 100 according to an embodiment of the present invention is shown. The cleaning appliance 100 can be a vacuum cleaner, such as the one described above with respect to Figure 1 described above.

[0046] The cleaning appliance 100 includes a main body 110 and a cleaner head 120, wherein the main body 110 is configured to supply power to the cleaner head 120 via a plurality of conductors 130. Specifically, as Figure 2As shown, the plurality of conductors 130 includes three conductors and they may be in the form of, for example, wires. However, it should be understood that according to certain embodiments of the present invention, the plurality of conductors 130 may include only two conductors (e.g., in the case where the motor in the cleaner head 120 is a brushed motor), and thus one of the conductors 130 is shown as a dashed line to emphasize that embodiments of the present invention may include any suitable number of conductors 130.

[0047] The body 110 includes a first controller 111, such as including a PCBA, which may be the main controller of the cleaning appliance 100, such that it is responsible for other operations of the cleaning appliance 100 (e.g., controlling the vacuum motor within the body 110) as well as communication via the plurality of conductors 130 as described herein. The body 110 also includes a power PCBA 112, and the power PCBA 112 may obtain power from, for example, a battery pack. The power PCBA 112 supplies power to a three-phase inverter 113 for driving a brushless DC (BLDC) motor 121 located in the cleaner head 120, and the power is delivered from the inverter 113 to the BLDC motor 121 using the plurality of conductors 130. The first controller 111 is configured to send instructions to the power PCBA 112 for controlling the BLDC motor 121 to modulate the power supply for controlling the components 124 of the cleaner head 120, as described in more detail below. For example, the cleaning appliance 100 may include a storage device (e.g., on the same PCBA as the first controller 111) storing instructions, which when executed, cause the first controller 111 to perform the control method described below.

[0048] The cleaner head 120 includes a BLDC motor 121, which receives power from the body 110 via the plurality of conductors 130. The three-phase inverter 113 in the body 110 is configured to drive the BLDC motor 121. However, as described above, it should be understood that in certain embodiments of the present invention, the motor in the cleaner head 120 may be a brushed motor, and only two conductors are required to pass between the body 110 and the cleaner head 120.

[0049] The cleaner head includes component 124, which can be any additional component that can advantageously be controlled from the main body 110 (e.g., controllable by the user of the cleaning appliance 100). For example, component 124 can be a light-emitting diode (e.g., illuminating a dark area to be cleaned), a laser (e.g., illuminating dust and other large particles for better targeting of the area to be cleaned), or an actuator (e.g., a mechanical actuator can be used to move a part of the cleaner head 120, such as a lid or closure over a hole in the cleaner head 120, which can be opened to allow large particles to be picked up by the cleaning appliance 100 in use). For example, in response to a detected modulation, the second controller 123 can control the LED or laser to turn on or off, or can operate the actuator (e.g., open or close a hole in the cleaner head 120).

[0050] The cleaner head 120 includes a second controller 123 configured to detect a modulation of the power supply from the main body 110 and to control component 124 in response to such detection. For example, the second controller 123 can be implemented as a hardware circuit or a microcontroller. In some embodiments, the cleaner head can include more than one component, each of which can be controlled by the second controller 123 in response to different detected modulations in the power supply. Additionally or alternatively, the second controller 123 can be configured to decode a message that the first controller 111 has encoded in the power supply modulation. For example, such a message can be used to determine which of the multiple components in the cleaner head 120 will be controlled by the second controller 123.

[0051] To supply power to the second controller 123 and component 124, the cleaner head 120 includes a parasitic power supply 122 that is connected to obtain power from a plurality of conductors 130.

[0052] Figure 3 is a flowchart showing a method 200 of operating a cleaning appliance according to an embodiment of the present invention. For example, method 200 can be applicable to the cleaning appliance 100 as described above with respect to Figure 2 the cleaning appliance described above. In particular, method 200 can be used for a cleaning appliance (e.g., a vacuum cleaner) including a main body and a cleaner head, where the main body is configured to supply power to the cleaner head via a plurality of conductors.

[0053] In a first step 201, the power supply from the main body to the cleaner head is modulated. For example, the first controller in the main body can control the power supply to be modulated. Modulating the power supply can include pausing the power supply for a predetermined period or a short period (e.g., 3 - 4 ms), adjusting the PWM frequency of the power supply, and / or adjusting the PWM pulse width of the power supply. In some examples, modulating the power supply can include forming a modulation sequence, as described in more detail below.

[0054] In a second step 202, a modulation of the power supply is detected at the cleaner head. For example, a second controller in the cleaner head can detect the modulation.

[0055] In a third step 203, the modulation type is determined. For example, it is determined whether the modulation in the power supply is a first modulation type (e.g., a pause in the power supply) or a second type (e.g., an adjustment of the PWM frequency in the power supply). For example, a second controller in the cleaner head determines the modulation type.

[0056] Finally, in step 204, in response to the detection of the modulation and the determination of the modulation type, components of the cleaner head are controlled (e.g., by a second controller of the cleaner head). For example, the components to be controlled may depend on the type of modulation. For example, in response to determining that the modulation is a first type (e.g., a pause in the power supply), a first component can be controlled, or in response to determining that the modulation is a second type (e.g., an adjustment of the PWM frequency in the power supply), a second component can be controlled.

[0057] Figure 4 is a flowchart showing another method 300 of operating a cleaning appliance according to an embodiment of the present invention. For example, method 300 may be applicable to the cleaning appliance 100 as described above with respect to Figure 2 the cleaning appliance described. In particular, method 300 can be used for a cleaning appliance (e.g., a vacuum cleaner) including a main body and a cleaner head, wherein the main body is configured to supply power to the cleaner head via a plurality of conductors.

[0058] In a first step 301, the power supply from the main body to the cleaner head is modulated to encode a message. For example, a first controller in the main body can control the power supply to be modulated. Modulating the power supply to encode a message can include pausing the power supply for a predetermined period or a short period (e.g., 3 - 4 ms), adjusting the PWM frequency of the power supply, and / or adjusting the PWM pulse width of the power supply, wherein such an arrangement of modulation can encode a message (as described in more detail below).

[0059] In a second step 302, a modulation of the power supply is detected at the cleaner head. For example, a second controller in the cleaner head can detect the modulation.

[0060] In a third step 303, the message is decoded from the demodulation at the cleaner head. For example, a second controller in the cleaner head can decode the message.

[0061] Finally, in step 304, in response to the detected modulation and based on the decoded message, the components of the cleaner head are controlled (e.g., by a second controller of the cleaner head). For example, the cleaner head may include multiple components, and the components to be controlled may be determined by the content of the decoded message. In other examples, the type of control to be performed (e.g., on or off, or adjusting the power level) may be determined based on the content of the decoded message.

[0062] Figure 5 An example of power modulation and related control of components in a cleaner head of a cleaning appliance is shown, which can be used in embodiments of the present invention. The first graph 410 shows the power supply to the cleaner head over time, and the second graph 420 shows the state of the components of the cleaner head, which are controlled by a second controller. In this example, the components of the cleaner head can be "on" or "off", but it should be understood that there can be other control operations or operating modes, and they can depend on, for example, the components being controlled. In this example, the components to be controlled can be, for example, a laser or a lamp, which can be turned on or off by the second controller. For example, such control can originate from a user input, such as an input at the body of the cleaning appliance.

[0063] In the cleaning appliance, the body includes a first controller configured to modulate the power supply to the cleaner head. As shown in graph 410, the power supply to the cleaner head (e.g., a BLDC motor within the cleaner head) includes two modulations 411a, 411b. For example, each modulation 411a, 411b can be a pause in the power supply, an adjustment of the PWM frequency of the power supply (e.g., during each modulation 411a, 411b, the frequency changes from 30KHz in normal operation to 60KHz), or an adjustment of the PWM pulse width of the power supply. These modulations are triggered by the first controller, e.g., in response to a user input, in order to control the components of the cleaner head.

[0064] As shown in graph 420, before the first modulation 411a, the second controller operates the component to turn it on. However, when the second controller detects the first modulation 411a, the second controller controls the component to switch to the off state. The off state of the component is maintained until the second modulation 411b is detected, whereupon the second controller controls the component to switch to the on state.

[0065] As Figure 5 shown, the second controller can detect the end of the modulation, e.g., the time when the normal power supply is restored after a pause in the power supply, or the time when the normal PWM frequency is restored after an adjustment of the PWM frequency, and operate the component based on that detection. Of course, in other embodiments, the second controller can detect the start of the modulation, or another time point in the modulation.

[0066] Figure 6 Shows a second example of power modulation and associated control of components in a cleaner head, which can be used in embodiments of the present invention. The first graph 510 shows the power supply to the cleaner head over time, and the second graph 520 shows the state of the components of the cleaner head controlled by the second controller over time. In this example, the components of the cleaner head can be "on" or "off", but it should be understood that there can be other control operations or operating modes, and it can depend on, for example, the components being controlled. In this example, the components being controlled can be, for example, a laser or a lamp, which can be turned on or off by the second controller. For example, such control can originate from user input, such as an input at the body of the cleaning appliance. The body includes a first controller configured to modulate the power supply to the cleaner head.

[0067] As shown in graph 510, in this example, the first controller modulates the power supply to form modulation sequences 511a, 511b... 511n. For example, each modulation 511a, 511b... 511n can be a pause in the power supply, or an adjustment of the PWM frequency of the power supply (e.g., during each modulation 511a, 511b... 511n, the frequency changes from 30KHz in normal operation to 60KHz), or an adjustment of the PWM pulse width of the power supply. For example, the modulation sequence can last for a predetermined period of time, or the duration of the modulation sequence can be controlled based on user input. The modulation sequences 511a, 511b... 511n can be spaced at regular time intervals and / or regular frequency intervals to assist the second controller of the cleaner head in detection. In this way, the regular intervals of the modulation sequences 511a, 511b... 511n can be said to form a "heartbeat" that can be detected by the second controller.

[0068] Before detecting the modulation sequences 511a, 511b... 511n, the second controller operates the component so that it is off, as shown in graph 520. However, when the second controller detects the modulation sequences 511a, 511b... 511n, the second controller controls the component to switch to the on state (e.g., turn on the laser or lamp). The on state is maintained until the second controller no longer detects the modulation sequences 511a, 511b... 511n, whereupon the second controller controls the component to switch to the off state.

[0069] Figure 7Shows a third example of power modulation and associated control of components in a cleaner head, which can be used in embodiments of the present invention. In particular, the third example shows how modulation of the power supply is used for unidirectional communication from the main body of the cleaning appliance to the cleaner head. The first graph 610 shows the power supply to the cleaner head over time, where the modulation in the power supply encodes a message, and the second graph 620 shows how the modulation in the power supply is decoded (e.g., by a second controller) to obtain the message.

[0070] In this example, the first controller modulates the power supply to encode a message, as shown in graph 610. For example, the modulation in the power supply can be detected and decoded as '0' by the second controller, and the period in the power supply can be detected and decoded as '1' by the second controller. In this way, unidirectional communication from the main body to the cleaner head can occur.

[0071] For example, to encode a first message (MSG1), the first controller can encode '0100' in the power supply by providing a first modulation 611a of a predetermined length, followed by a period 611b without modulation of the same length, and a second modulation 611c twice the predetermined length. This is detected by the second controller, which decodes the message to output '0100', as shown in graph 620. For example, the first message can be an instruction to control a first component of the cleaner head, or to perform some specific control operation.

[0072] Similarly, to encode a second message (MSG2), the first controller can encode '0101' in the power supply by providing a first modulation 611d of a predetermined length, followed by a period 611e without modulation of the same length and a second modulation 611f of the same predetermined length, and a final period 611g without modulation. This is detected by the second controller, which decodes the message to output '0101', as shown in graph 620. For example, the second message can be an instruction to control a second component of the cleaner head, or to perform some specific control operation.

[0073] Figure 8 Shows a fourth example of power modulation and associated control of components in a cleaner head, which can be used in embodiments of the present invention. In particular, the fourth example shows how two-way communication can be achieved between the main body and the cleaner head. In particular, in this example, during a period when the power supply to the motor is turned off (e.g., during a power supply pause), the cleaner head communicates with the main body (e.g., by generating and sending a communication signal to the main body).

[0074] In this fourth example, the first controller modulates the power supply to encode a message in a very similar way to that described above with reference to Figure 7 described, particularly inFigure 7 In an embodiment, the modulation of the power supply is a brief pause. Accordingly, the description of these features is not repeated, and like reference numerals are used to denote like features. Generally, however, the first graph 610 shows the power supply to the cleaner head over time, where the modulation in the power supply (where these modulations are brief pauses in the power supply) encodes a message from the body to the cleaner head, and the second graph 620 shows how the modulation in the power supply is decoded (e.g., by a second controller) to obtain the message. The third graph 710 shows the communication signals 711, 712 from the cleaner head to the body, where the communication signals can be decoded (e.g., by a first controller). The communication signals 711, 712 can be used as feedback, e.g., to enhance the body's control of the cleaner head (e.g., by a first controller). For example, the cleaner head can include one or more sensors (e.g., temperature or pressure sensors), and the second controller can use the two-way communication capability to notify the body of critical hardware operations (e.g., cleaner head clogging or hardware within the cleaner head being above a predetermined temperature). For example, the communication signals 711, 712 can include pulses (e.g., pulses of variable length) or multiple pulses. In an embodiment, each pulse can be a power pulse along multiple conductors. Another example of how to implement such communication signals 711, 712 is described below with reference to FIG. 9.

[0075] During a brief pause in the power supply to the cleaner head, the body (e.g., a first controller) can be configured to observe the state of the motor in the cleaner head. This is typically accomplished by monitoring the back electromotive force (BEMF). The second controller can thus send the communication signals 711, 712 by modifying the BEMF. For example, the second controller can perform what is referred to as "motor active braking" by creating a short circuit between two of the multiple conductors. In another example, the second controller can create an open circuit on one of the multiple conductors to indicate an open circuit on one of the motor phases such that the BEMF cannot be detected by the body. FIG. 9 shows an example circuit diagram of how the second controller generates such communication signals (a portion of the circuit within the cleaner head, e.g., the cleaner head 120 as described above).

[0076] Figure 9a The circuit diagram is shown where the second controller 123 is configured to control a switch 801, and the switch 801 is arranged to create a short circuit between two of the multiple conductors 130 when the switch 801 is closed. In this way, the second controller 123 can send a communication signal that can be detected by the first controller in the body as an interruption in the back electromotive force (BEMF) normally sensed by the first controller. For example, the switch 801 can be a bidirectional power supply switch, or any other suitable controllable switch.

[0077] Figure 9b A circuit diagram is shown, in which a second controller 123 is configured to control a switch 802, and the switch 802 is arranged to create an open circuit on one of a plurality of conductors 130 when the switch 802 is open. In this way, the second controller 123 can send a communication signal that can be detected by a first controller in the body as an interruption in the BEMF that is normally sensed by the first controller. For example, the switch 802 can be a bi-directional power supply switch, or any other suitable controllable switch.

[0078] Features disclosed in the foregoing description, or in the following claims, or in the drawings, expressed in their specific forms or in terms of means for performing the disclosed functions, or in terms of methods or processes for obtaining the disclosed results, may, where appropriate, be used alone or in any combination of these features to implement the invention in its various forms.

[0079] Although the invention has been described in connection with the above exemplary embodiments, many equivalent modifications and variations will be apparent to those skilled in the art when the present disclosure is given. Accordingly, the above exemplary embodiments of the invention are considered to be illustrative and not restrictive. Various changes may be made to the described embodiments without departing from the spirit and scope of the invention.

[0080] To avoid any doubt, any theoretical explanations provided herein are for the purpose of enhancing the reader's understanding. The inventors do not wish to be bound by any of these theoretical explanations.

[0081] Any chapter headings used herein are for organizational purposes only and should not be construed as limiting the subject matter described.

[0082] Throughout the specification, including the claims that follow, unless the context requires otherwise, the words "comprise" and "include", and variations such as "comprises", "includes" and "including" will be understood to imply the inclusion of the stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

[0083] It must be noted that, as used in the specification and the appended claims, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" one particular value, and / or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations by use of the antecedent "about", it will be understood that the particular value forms another embodiment. The term "about" associated with a numerical value is optional and means, for example, + / -10%.

Claims

1. A cleaning appliance, comprising a main body and a cleaning head, wherein the main body is configured to supply power to the cleaning head via a plurality of conductors, wherein: the main body includes a first controller configured to modulate the power supply to the cleaning head, and the cleaning head includes a second controller configured to detect the modulation in the power supply and control components of the cleaning head in response to the modulation.

2. The cleaning appliance according to claim 1, wherein the plurality of conductors includes three conductors.

3. The cleaning appliance according to claim 1 or 2, wherein the main body includes a three-phase inverter for driving a motor in the cleaning head.

4. The cleaning appliance according to any one of the preceding claims, wherein the second controller includes: a hardware circuit; or a microcontroller.

5. The cleaning appliance according to any one of the preceding claims, wherein the first controller is configured to modulate the power supply by at least one of the following: suspending the power supply; adjusting the pulse width modulation (PWM) frequency of the power supply; and / or adjusting the PWM pulse width of the power supply.

6. The cleaning appliance according to claim 5, wherein the first controller is configured to modulate the power supply by suspending the power supply, and wherein the second controller is configured to communicate with the first controller during the suspension of the power supply.

7. The cleaning appliance according to claim 6, wherein the second controller is configured to communicate with the first controller by at least one of the following: creating a short circuit between two of the plurality of conductors; and creating an open circuit on one of the plurality of conductors.

8. The cleaning appliance according to any one of claims 5 to 7, wherein the first controller is configured to modulate the power supply to form a modulation sequence, and wherein the second controller is configured to detect the modulation sequence.

9. The cleaning appliance according to any one of claims 5 to 7, wherein the cleaning head includes a first component and a second component, and wherein the second controller is configured to: control the first component in response to detecting that the modulation is a first modulation type; and control the second component in response to detecting that the modulation is a second modulation type.

10. The cleaning appliance according to any one of the preceding claims, wherein the first controller is configured to modulate the power supply to the cleaning head to encode a message; and wherein the second controller is configured to decode the message from the modulation.

11. The cleaning appliance according to any one of the preceding claims, wherein the components of the cleaning head are any one or more of the following: light-emitting diodes; lasers; and / or mechanical actuators.

12. A method of operating a cleaning appliance, the cleaning appliance including a main body and a cleaning head, wherein the main body is configured to supply power to the cleaning head via a plurality of conductors; wherein the method includes: modulating, at the main body, the power supply to the cleaning head; detecting, at the cleaning head, the modulation of the power supply; and controlling, in response to the detection, components of the cleaning head.

13. The method of operating a cleaning appliance according to claim 12, wherein modulating the power supply to the cleaning head comprises at least one of the following: Suspending the power supply; Adjusting the pulse width modulation (PWM) frequency of the power supply; and / or Adjusting the PWM pulse width of the power supply.

14. The method of operating a cleaning appliance according to claim 11, wherein modulating the power supply to the cleaning head comprises suspending the power supply, and wherein the method further comprises generating a signal from the cleaning head to the body during the suspension of the power supply.

15. The method of operating a cleaning appliance according to claim 14, wherein generating the signal comprises at least one of the following: Creating a short circuit between two of the plurality of conductors; and Creating an open circuit on one of the plurality of conductors.

16. The method of operating a cleaning appliance according to any one of claims 13 to 15, wherein modulating the power supply to the cleaning head comprises forming a modulation sequence such that the modulation sequence is detectable at the cleaning head.

17. The method of operating a cleaning appliance according to any one of claims 13 to 15, wherein the cleaning head comprises a first component and a second component, and wherein the method further comprises: Determining the type of modulation of the power supply at the cleaning head; and, alternatively: Controlling the first component in response to determining that the modulation is a first modulation type; Or Controlling the second component in response to determining that the modulation is a second modulation type.

18. The method of operating a cleaning appliance according to any one of claims 12 to 17, wherein modulating comprises modulating the power supply to the cleaning head to encode a message, and wherein the method further comprises decoding the message from the modulation at the cleaning head.

19. The cleaning appliance according to any one of claims 1 to 11, wherein the cleaning appliance comprises a storage device storing instructions which, when executed, cause the first controller and the second controller to perform the control method according to any one of claims 12 to 18.

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