FIELD OF THE INVENTION
[0001] The subject-matter of the present disclosure relates to personal care appliances
and determining when an operational head of a personal care appliance requires replacing,
plus transitory, or non-transitory, computer-readable media.
BACKGROUND OF THE INVENTION
[0002] Personal care appliances, such as hair cutting devices, often include a cutter. The
cutter, when first installed to the personal care appliance, is sharp and cuts or
shaves hair well. However, over time, the cutter or shaving device becomes more blunt
and requires replacing.
[0003] Generating a replacing signal for a user can be difficult because different users
have different hair types. For example, one user may have a dense beard with thick
hair. Another use may have a sparse beard with finer hair. The former will blunt the
cutter quicker than the latter.
[0004] It is an aim of the subject-matter of the present disclosure to improve on the prior
art.
SUMMARY OF THE INVENTION
[0005] According to a first aspect of the present invention, there is provided a computer-implemented
method of determining when an operational head of a personal care appliance needs
to be replaced, the computer-implemented method comprising: monitoring an operational
parameter sensed by a sensor of the personal care appliance, the operational parameter
associated with operating the operational head; determining values based on the operational
parameter over time; determining an energy used in operating the operational head
over time based on the values; determining that the operational head needs to be replaced
based on changes of the energy over time; and sending a signal indicating that the
operational heads to be replaced in response to the determining that the operational
head needs to be replaced. By determining that the operational head needs replacing
based on changes of the energy over time, the determination is based on how the personal
care appliance operates on that specific user. In this way, the determination is tailored
to the specific user.
[0006] In an embodiment, the determining the values based on the operational parameter over
time comprises: measuring, using the sensor, real time values of the operational parameter;
and subtracting free-running values of the operational parameter from the real time
values of the operational parameter.
[0007] In an embodiment, the subtracting the real time values based on operational parameter
from the free-running value of the operational parameter comprises: monitoring a real
time free-running value of the operational parameter; and subtracting the real time
free-running value of the operational parameter from the real time value of the operational
parameter.
[0008] In an embodiment, the monitoring the real time free-running value of the operational
parameter comprises determining the real time free-running value of the operational
parameter by: using a low-pass filter on the real time values of the operational parameter
to discard values above a threshold; calculating a moving minimum value from the real
time values of the operational parameter; or calculating a moving 1st percentile value
from the real time values of the operational parameter.
[0009] In an embodiment, the determining that the operational head needs to be replaced
based on changes of the energy over time comprises: calculating a cumulative energy
over time using the determined energy; comparing the cumulative energy to an energy
threshold; and determining that the operational head needs to be replaced based on
the comparison.
[0010] In an embodiment, the determining that the operational head needs to be replaced
based on the comparison comprises determining that the operational head needs to be
replaced when the cumulative energy is greater than or equal to the energy threshold.
[0011] In an embodiment, the personal care appliance comprises a motor for operating the
operational head, in-use, and wherein the operational parameter is power or current
of the motor.
[0012] In an embodiment, the determining the energy used in operating the operational head
over time based on the values based on operational parameter comprises integrating
the determined values over time.
[0013] In an embodiment, the personal care appliance is a trimmer or a shaver, and the operational
head is a trimmer.
[0014] In an embodiment, the sending a signal indicating that the operational head is to
be replaced in response to the determining that the operational head needs to be replaced
comprises sending a signal to a display device to display a notification to a user
to replace the operational head.
[0015] In an embodiment, the display device is a remote device, or a display device mounted
to the personal care appliance.
[0016] According to an aspect of the present invention, there is provided a transitory,
or non-transitory, computer-readable medium, having instructions stored thereon that
when executed by one or more processors, cause the one or more processors to perform
the computer-implemented method of any preceding aspect or embodiment.
[0017] According to an aspect of the present invention, there is provided a personal care
appliance comprising: a handle; a sensor coupled to the handle; an attachment for
attaching an operational head to the handle; and a controller having a processor and
storage, wherein the storage has instructions stored thereon that, when executed by
the processor, cause the processor to perform the computer-implemented method of any
preceding aspect or embodiment.
[0018] These and other aspects of the present invention will be apparent from and elucidated
with reference to the embodiment(s) described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The embodiments of the present inventions may be best understood with reference to
the accompanying figures, in which:
Fig. 1 shows a block diagram of a personal care appliance according to one or more
embodiments;
Fig. 2 shows a series of parameter values captured over time for respective new and
worn operational heads of the personal care appliance;
Fig. 3 shows operational values measured from a sensor of the personal care appliance
over time, and their breakdown into a component attributable to operating the operational
head and a component attributable to a free-running motor of the personal care appliance,
according to one or more embodiments;
Fig. 4 shows a graph for use in determining the free-running values from the measured
values, according to one or more embodiments;
Fig. 5 shows a graph showing cumulative energy over a number of shaves compared to
a cumulative energy replacement threshold; and
Fig. 6 shows a flow chart summarising a computer-implemented method of determining
whether an operational head of a personal care appliance requires replacing.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] At least some of the example embodiments described herein may be constructed, partially
or wholly, using dedicated special-purpose hardware. Terms such as 'component', 'module'
or 'unit' used herein may include, but are not limited to, a hardware operational
head, such as circuitry in the form of discrete or integrated components, a Field
Programmable Gate Array (FPGA) or Application Specific Integrated Circuit (ASIC),
which performs certain tasks or provides the associated functionality. In some embodiments,
the described elements may be configured to reside on a tangible, persistent, addressable
storage medium and may be configured to execute on one or more processors. These functional
elements may in some embodiments include, by way of example, components, such as software
components, object-oriented software components, class components and task components,
processes, functions, attributes, procedures, subroutines, segments of program code,
drivers, firmware, microcode, circuitry, data, databases, data structures, tables,
arrays, and variables. Although the example embodiments have been described with reference
to the components, modules and units discussed herein, such functional elements may
be combined into fewer elements or separated into additional elements. Various combinations
of optional features have been described herein, and it will be appreciated that described
features may be combined in any suitable combination. In particular, the features
of any one example embodiment may be combined with features of any other embodiment,
as appropriate, except where such combinations are mutually exclusive. Throughout
this specification, the term "comprising" or "comprises" means including the component(s)
specified but not to the exclusion of the presence of others.
[0021] With reference to Fig. 1, a personal care appliance 100 according to one or more
embodiments includes a handle 102, an attachment 104, an operational head 106, a power
source 108, a controller 110, a motor 112, a sensor 114, and a display 116.
[0022] The personal care appliance 100 may be a hair removal appliance such as a trimmer
or a shaver, for example. The operational head 106 is a device that performs and operation,
e.g. hair removal. The operational head may be a trimmer. The trimmer includes a guard
and a cutter. The cutter and the guard each comprise teeth which cut hair there between
when the cutter moves reciprocally over the guard.
[0023] The attachment 104 attaches the operational head 106 to the handle 102.
[0024] The power source 108 may be a battery, e.g. a secondary, or rechargeable, battery.
[0025] The controller 110 may include storage and one or more processors. The storage includes
electronic data in the form of instructions. The instructions, when executed by the
one or more processors, may cause the one or more processors to perform the computer-implemented
methods described herein. In this way, the storage may be non-transitory computer
readable media. The instructions may also be provided as transitory computer-readable
media when provided as a download to be stored on the storage.
[0026] The motor 112 may consume energy from the power source 108 when operating. This energy
may be sensed by the sensor 114. The sensor sensed an operational parameter associated
with operating the operational head. The operational parameter being current or power.
[0027] The display 116 may be mounted to an exterior surface of the handle 102 and communicatively
linked to the controller so as to display indications generated by the controller.
[0028] With reference to Fig. 2, both graphs show operational parameter values cycling between
values associated with cutting hair and values associated with a free-running motor.
The values of a free-running motor are associated with the troughs 202 and the values
of cutting hair are associated with the peaks 204. Also shown on each graph is an
average value line 206, a value plus 10% of the average value 208, and a value minus
10% of the average value 210. The upper figure is associated with a brand-new cutter.
The lower figure is associated with a worn cutter. It can be seen that the amplitude
between values associated with cutting hair and values associated with a free-running
motor is larger for the worn cutting element, and therefore the +10% lines 208, 210,
are farther apart.
[0029] Therefore, it can be seen that the operational parameter values can be used for determining
when the operational head needs replacing since there are differences between worn
and brand-new cutters.
[0030] Embodiments provide a computer-implemented method of determining when an operational
head of a personal care appliance requires replacing that addresses this need. The
method includes monitoring an operational parameter sensed by a sensor of the personal
care appliance, the operational parameter associated with operating the operational
head; determining values based on the operational parameter over time; determining
an energy used in operating the operational head over time based on the values; determining
that the operational head needs to be replaced based on changes of the energy over
time; and sending a signal indicating that the operational heads to be replaced in
response to the determining that the operational head needs to be replaced.
[0031] With reference to Fig. 3, the determining the values based on, or of, the operational
parameter over time for each use comprises, for each use: measuring, using the sensor,
real time values of the operational parameter; and subtracting the real time values
302 of the operational parameter from a free-running value 306 of the operational
parameter. The result of the subtraction is the values of the operational parameter
304.
[0032] This method is shown in Fig. 3 when the free-running value 306 is constant. This
is an approximation method.
[0033] With reference to Fig. 4, a more accurate method is provided where the wherein the
subtracting the real time values of the operational parameter from the free-running
value of the operational parameter comprises: monitoring a real time free-running
value 402 of the operational parameter; and subtracting the real time value 404 of
the operational parameter from the real time free-running value of the operational
parameter over time. The result of the subtraction is the real time values 406. The
method associated with Fig. 4 is more accurate than the method associated with Fig.
3 because the free-running values are in real-time, i.e. they are continually updated
and not assumed to be constant.
[0034] It is possible to obtain the real-time free running value 402 in various ways. For
instance, it is possible to determine the real time free-running value of the operational
parameter by using a low-pass filter on the real time values 404 of the operational
parameter to discard values above a threshold. The threshold may be set at what is
known to be a free-running value of a motor for example. Another way is to calculate
a moving minimum value from the real time values of the operational parameter. The
moving minimum uses a time window which moves with time. A minimum real time value
404 in the window is obtained and is used as the real-time free running value 402.
Another way is to calculate a moving nth percentile value from the real time values
of the operational parameter. The nth percentile may be a 1
st, 2
nd or even a 3
rd percentile, for example, although other percentiles may be used too.
[0035] With reference to Fig. 5, the determining that the operational head needs replacing
based on changes of the energy over time comprises: calculating a cumulative energy
over time using the determined energy; comparing the cumulative energy to an energy
threshold; and determining that the operational head needs to be replaced based on
the comparison.
[0036] The determining an energy used in operating the operational head over time based
on the values comprises integrating the power values over time. This is visualised
as integrating an area under a curve of the values 406 in Fig. 4. This may be done
numerically rather than analytically. The cumulative energy is calculated by adding
energy values for each shave to a total cumulative energy,
Ecutting_cumulative, value of all shaves since the current cutter has been attached to the personal care
appliance. The energy threshold, or energy replacement threshold,
Ereplace, may be predetermined.
[0037] As shown in Fig. 5, the time, or number of shaves, to reach the energy replacement
threshold,
Ereplace, is less for a heavy beard than a light beard. A heavy beard is defined as a beard
that is dense and/or has thick hair. A light beard is a beard that is sparse and/or
has thin hair. It will be appreciated that when the cumulative energy,
Ecutting_cumulative, is greater than or equal to the energy threshold,
Ereplace.
[0038] Finally, the sensing the signal indicating that the operational head needs to be
replaced when the determining that the operational head needs to be replaced comprises
sending a signal to the display 116 (Fig. 1) to display a notification to a user to
replace the operational head. The display in Fig. 1 is a display mounted to the personal
care appliance but the display may also be a display of a remote device.
[0039] With reference to Fig. 6, a computer-implemented method of determining when an operational
head of a personal care appliance requires replacing is summarised as including the
steps of: monitoring 700 an operational parameter sensed by a sensor of the personal
care appliance, the operational parameter associated with operating the operational
head; determining 702 values based on the operational parameter over time; determining
704 an energy used in operating the operational head over time based on the values;
determining 706 that the operational head needs to be replaced based on changes of
the energy over time; and sending 708 a signal indicating that the operational heads
to be replaced in response to the determining that the operational head needs to be
replaced.
[0040] While the invention has been illustrated and described in detail in the drawings
and foregoing description, such illustration and description are to be considered
illustrative or exemplary and not restrictive; the invention is not limited to the
disclosed embodiments.
[0041] Other variations to the disclosed embodiments can be understood and effected by those
skilled in the art in practicing the claimed invention, from a study of the drawings,
the disclosure, and the appended claims. In the claims, the word "comprising" does
not exclude other elements or steps, and the indefinite article "a" or "an" does not
exclude a plurality. A single processor or other unit may fulfil the functions of
several items recited in the claims. The mere fact that certain measures are recited
in mutually different dependent claims does not indicate that a combination of these
measured cannot be used to advantage. Any reference signs in the claims should not
be construed as limiting the scope.
1. A computer-implemented method of determining when an operational head (106) of a personal
care appliance (100) needs to be replaced, the computer-implemented method comprising:
monitoring (700) an operational parameter sensed by a sensor (114) of the personal
care appliance, the operational parameter associated with operating the operational
head;
determining (702) values based on the operational parameter over time;
determining (704) an energy used in operating the operational head over time based
on the values;
determining (706) that the operational head needs to be replaced based on changes
of the energy over time; and
sending (708) a signal indicating that the operational heads to be replaced in response
to the determining that the operational head needs to be replaced.
2. The computer-implemented method of Claim 1, wherein the determining the values (406)
based on the operational parameter over time comprises:
measuring, using the sensor, real time values (404) of the operational parameter;
and
subtracting free-running values (402) of the operational parameter from the real time
values of the operational parameter.
3. The computer-implemented method of Claim 2, wherein the subtracting the real time
values based on operational parameter from the free-running value of the operational
parameter comprises:
monitoring a real time free-running value of the operational parameter; and
subtracting the real time free-running value of the operational parameter from the
real time value of the operational parameter.
4. The computer-implemented method of Claim 3, wherein the monitoring the real time free-running
value of the operational parameter comprises determining the real time free-running
value of the operational parameter by:
using a low-pass filter on the real time values of the operational parameter to discard
values above a threshold;
calculating a moving minimum value from the real time values of the operational parameter;
or
calculating a moving nth percentile value from the real time values of the operational parameter.
5. The computer-implemented method of any preceding claim, wherein the determining that
the operational head needs to be replaced based on changes of the energy over time
comprises:
calculating a cumulative energy over time using the determined energy;
comparing the cumulative energy to an energy threshold; and
determining that the operational head needs to be replaced based on the comparison.
6. The computer-implemented method of Claim 5, wherein the determining that the operational
head needs to be replaced based on the comparison comprises determining that the operational
head needs to be replaced when the cumulative energy is greater than or equal to the
energy threshold.
7. The computer-implemented method of any preceding claim, wherein the personal care
appliance comprises a motor (112) for operating the operational head, in-use, and
wherein the operational parameter is power of the motor.
8. The computer-implemented method of Claim 7, wherein the determining an energy used
in operating the operational head over time based on the values based on operational
parameter comprises integrating the determined values over time.
9. The computer-implemented method of any preceding claim, wherein the personal care
appliance is a shaver, and the operational head is a trimmer
10. The computer-implemented method of any preceding claim, wherein the sending a signal
indicating that the operational head is to be replaced in response to the determining
that the operational head needs to be replaced comprises sending a signal to a display
device (116) to display a notification to a user to replace the operational head.
11. The computer-implemented method of Claim 10, wherein the display device is a remote
device, or a display device mounted to the personal care appliance.
12. A transitory, or non-transitory, computer-readable medium, having instructions stored
thereon that when executed by one or more processors, cause the one or more processors
to perform the computer-implemented method of any preceding claim.
13. A personal care appliance (100) comprising:
a handle (102);
a sensor (114) coupled to the handle;
an attachment (104) for attaching an operational head to the handle; and
a controller (110) having a processor and storage, wherein the storage has instructions
stored thereon that, when executed by the processor, cause the processor to perform
the computer-implemented method of any of Claims 1 to 11.