Patent Description:
Personal care appliances may include a durable component, such as a handle that is reused and a replaceable component, such as a cartridge that needs to be replaced after a certain amount of uses. Examples of personal care appliances may include, but are not limited to facial cleanser devices, toothbrushes and shaving razors. Replaceable cartridges may last for a month, or even longer. Thus, consumers typically lose track of how many times they have used the replaceable cartridges. Furthermore, performance of the replaceable cartridges may gradually decrease over time. Accordingly, the consumer may be less likely to perceive any performance changes that would indicate a new cartridge is needed.

A shaving razor or other personal care appliance may count the number of usages and feedback this information to the consumer. For some devices the manufacturer may recommend exchanging an attachment (e.g., cartridge) after a certain time of usage as some attachments decrease their functionality over the time and replacing helps to retain the performance and additional benefits of the device.

Some personal care appliances may provide a sensor for detecting the presence of a replaceable cartridge which resets an internal counter. However, these are not passive systems and require light emitter(s) (e.g., light emitting diodes or LEDs). Drawbacks of optical detection systems is that they can confuse the presence of a cartridge with just a low ambient light condition, which may be typical of a dimly lit bathroom early in the morning or late at night. Other drawbacks of present cartridge detection systems include resetting the usage count without additional feedback from the consumer thus leading to potential unintended resets.

Prior art document <CIT> discloses a safety razor having a handle and a cartridge selectively detachable from the handle. The cartridge has at least one blade with a sharp cutting edge and an expected shaving utility. A connecting structure is coupled to the handle and attaches or detaches the cartridge from the handle in response to an action performed by a user. A detector within the handle has an actuator coupled to the connecting structure and a sensor for generating a signal, wherein the actuator applies an action on the sensor during the action and the sensor generates the signal in response to the action.

Accordingly, there is a need to provide a personal care appliance that is capable of sensing the presence of an attachment (e.g., cartridge) in in all reasonably assumable illumination settings including low ambient light without the need for LEDs and accurately track attachment usage.

The invention features, in general, a personal care appliance with a handle having a coupler at a first end. A control circuit is positioned within the handle. A consumer user interface is operably connected to the control circuit. A digital counter is operably connected to the control circuit. An optical sensor is mounted to the coupler that is configured to send an electrical output signal to the control circuit. A cartridge is removably mounted to the coupler. The cartridge has an opaque surface covering the optical sensor and blocking ambient light from reaching the optical sensor when mounted to the coupler. The control circuit is configured to determine an attachment status of the cartridge by comparing the electrical output signal to one or more predetermined thresholds or by detecting a change over time in the electrical output signal of the optical sensor.

Also disclosed, but not part of the claimed invention, is in general, a personal care appliance with a handle having a coupler at a first end. A control circuit is positioned within the handle. An optical sensor is positioned on the coupler and electrically connected to the control circuit. The optical sensor sends an electrical output signal to the control circuit. A cartridge is removably mounted to the coupler. The cartridge has an opaque surface covering the optical sensor and blocking ambient light from reaching the optical sensor. The coupler does not have a light emitter.

Also disclosed, but not part of the claimed invention, is in general, a method of resetting a digital counter for a personal care appliance by sending an electrical output signal from an optical sensor to a control circuit. The electrical output signal is compared to a predetermined value with the control circuit or a change in the electrical output signal from the optical sensor is detected over time. A signal is sent to a consumer user interface by the control circuit based on the electrical output signal and the predetermined value or based on the change in the electrical output signal from the optical sensor. The digital counter is reset based on an input signal from the consumer user interface.

Also disclosed, but not part of the claimed invention, is in general, a method of resetting a digital counter for a personal care appliance by sending an electrical output signal from an optical sensor to a control circuit. The electrical output signal is compared to a predetermined value with the control circuit or detecting a change over time in the electrical output signal from the optical sensor. A signal is sent to a smart device by the control circuit based on the electrical output signal and the predetermined value or based on the change over time in the electrical output signal from the optical sensor. The digital counter is reset based on an input signal the smart device.

Also disclosed, but not part of the claimed invention, is in general, a method of resetting a digital counter for a personal care appliance by sending an electrical output signal from an optical sensor to a control circuit. The electrical output signal is compared to at least one predetermined value with the control circuit or a change over time in the electrical output signal from the optical sensor is detected by the control circuit. A signal is sent from the control circuit to a cloud based on the electrical output signal of the optical sensor. A signal is sent from the cloud to a smart device or a consumer user interface on a personal care appliance. The digital counter is reset by sending a signal from the smart device or the consumer user interface to the digital counter.

Other features and advantages of the invention will be apparent from the description and drawings, and from the claims.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter that is regarded as the present invention, it is believed that the invention will be more fully understood from the following description taken in conjunction with the accompanying drawings.

Referring to <FIG> and <FIG>, one possible embodiment of the present disclosure is shown illustrating a personal care appliance <NUM>. The personal care appliance <NUM> may include a handle <NUM> having a coupler <NUM> at a first end <NUM> of the handle. A cartridge <NUM> may be removably mounted to the coupler <NUM>. The cartridge <NUM> may include one or more blades <NUM> for shaving. Although the personal care appliance <NUM> shown is a shaving razor, it is understood the personal care appliance may also include toothbrushes or other cosmetic devices having a replaceable cartridge. The handle <NUM> may include an optical sensor subassembly <NUM>. The optical sensor subassembly <NUM> may have at least one optical sensor (not shown) positioned within a pocket <NUM> of a housing <NUM>. The at least one optical sensor (not shown) may be mounted to a printed circuit board <NUM> (e.g., a flexible printed circuit board) that extends from the coupler to a cavity within the handle <NUM>. It is understood that in certain embodiments, the printed circuit board <NUM>, as well as other electrical components may be positioned outside of the handle <NUM> and sealed from water ingress. A consumer user interface <NUM> may be operably connected to a control circuit (not shown). In certain embodiments, the consumer user interface <NUM> may be positioned on the handle <NUM>. The consumer user interface (e.g., a touch screen) may provide information to the user and receive input from the user regarding the function of the personal care appliance <NUM>. It is understood that the consumer user interface <NUM> may also be physically separated from the handle <NUM>, such as on a smart device (e.g., a phone or watch) or computer in the form of an app or a push notification requesting an input from the user. In such situations the control circuit (not shown) may still be operably connected to the user interface <NUM> when the handle <NUM> is a connected handle that is wirelessly or wire connected to the smart device or computer having the consumer interface. The communication between handle <NUM> and user interface <NUM> may happen directly (e.g., peer-to-peer) or via an intermediate cloud service.

The cartridge <NUM> may define an opening <NUM> dimensioned to receive the coupler <NUM>. As will be explained in greater detail below, the opening <NUM> may be defined by an opaque surface <NUM> that covers the pocket <NUM> (e.g., in a planar direction) and the optical sensor (not shown) when the cartridge <NUM> is properly mounted to the coupler <NUM>. It is understood that tolerances may still allow for small gaps, thus it is understood the pocket <NUM> may not be completely covered. The opaque surface <NUM> may prevent any ambient light from reaching the optical sensor and may also prevent light from reflecting light towards the optical sensor (not shown). When the cartridge <NUM> is removed from the coupler <NUM>, ambient light may reach the optical sensor <NUM>.

Referring to <FIG>, a perspective view of an electronic subassembly <NUM> of the personal care appliance <NUM> of <FIG> is illustrated. The electronic subassembly <NUM> may be positioned within the handle <NUM> of <FIG>. The electronic subassembly <NUM> may include a control circuit <NUM> (e.g., a microcontroller). The control circuit <NUM> may be in electrical communication with the printed circuit board <NUM>, which is in electrical communication with an optical sensor <NUM> mounted to the printed circuit board <NUM>. The optical sensor <NUM> may produce one or more electrical output signals. For example, the optical sensor may produce an electrical output signal when ambient light is blocked from reaching the optical sensor <NUM> (e.g., the cartridge <NUM> is mounted to the coupler <NUM>, as shown in <FIG>). The optical sensor <NUM> may also produce the electrical output signal when ambient light is received by the optical sensor <NUM> (e.g., the cartridge <NUM> is separated from the coupler <NUM>, as shown in <FIG>). It is understood that the electrical output signal may change over time and as the cartridge <NUM> is mounted to the coupler <NUM> and removed from the coupler <NUM>.

The optical sensor <NUM> may be able to distinguish between a close to zero lux condition, in which the cartridge <NUM> is mounted to the coupler <NUM> and the opaque surface blocks ambient light and a low lux condition (e.g., <NUM> lux) in which the cartridge <NUM> is not mounted to the coupler <NUM>, but the personal care appliance <NUM> is in a dimly lit room. It is understood it may be difficult to achieve an absolute dark condition, even with the cartridge <NUM> mounted to the coupler <NUM>. Accordingly, the optical sensor <NUM> may send the electrical output signal to the control circuit <NUM> that corresponds to a reading from about zero lux to about <NUM> lux. The control circuit <NUM> may compare the electrical output signal to one or more predetermined threshold values. For example, the electrical output signal may be compared to a predetermined valued stored by the control circuit <NUM> that represents ambient light being blocked from the optical sensor. In certain embodiments, a first predetermined value may represent a condition of the cartridge <NUM> attached to the coupler <NUM>. If the electrical output signal is less than the first predetermined value, the control circuit <NUM> may determine the cartridge <NUM> is attached to the coupler <NUM>. If the electrical output signal is greater than or equal the first predetermined value, then the control circuit <NUM> may determine the cartridge <NUM> has been removed from the coupler <NUM>. As will explained in greater detail below, the control circuit <NUM> may send various signals depending if it determines the cartridge <NUM> is attached or removed from the coupler <NUM>.

In certain embodiments, the first predetermined value may not be determined by the manufacturer. For example, the control circuit <NUM> may run a diagnostic test to have the consumer determine the correct light level for the first predetermined value. The consumer user interface <NUM> (<FIG>) may ask the consumer to remove the cartridge <NUM>. The consumer may confirm via the consumer user interface <NUM> (<FIG>) the cartridge <NUM> (<FIG>) has been removed. The control circuit <NUM> may then have the optical sensor <NUM> send the electrical output signal, which may be stored by the control circuit <NUM>. The consumer user interface <NUM> may then ask the consumer to attach the cartridge <NUM> to the coupler <NUM> (<FIG>). The consumer may confirm via the consumer user interface <NUM> the cartridge <NUM> is attached (<FIG>). The control circuit <NUM> may then have the optical sensor <NUM> send the electrical output signal again, which may be stored by the control circuit <NUM>. If the consumer starts using the personal care appliance <NUM> (<FIG>) in different lighting conditions, then the consumer may run the diagnostic test again, but under the new lighting conditions.

Referring to <FIG>, a cross section view of the personal care appliance <NUM>, taken generally along the line <NUM>-<NUM> of <FIG> is illustrated. <FIG> shows the cartridge <NUM> mounted to the coupler <NUM>. The coupler <NUM> may be positioned within the opening <NUM> (<FIG>) with the opaque surface <NUM> positioned over (i.e., covering) the optical sensor <NUM>. The pocket <NUM> may be dimensioned to receive the optical sensor <NUM>. The optical sensor <NUM> may be positioned towards a lower portion <NUM> of the pocket <NUM> away from a top surface <NUM> of the coupler <NUM> that is adjacent to the opaque surface <NUM>.

The optical sensor <NUM> may include an over molded light guide <NUM>. The light guide <NUM> may facilitate guiding ambient light to the optical sensor <NUM> and may also prevent the optical sensor <NUM> from being damaged either physically (e.g., from being dropped) or chemically (e.g., by chemicals typically found in personal hygiene appliances). The light guide <NUM> may comprise a transparent or translucent material, which only influences the transmission of ambient light to the optical sensor <NUM> to an irrelevant extent. For example, materials may include silicone, thermoplastic elastomers, various curable liquid adhesives and/or polycarbonate. A softer material, such as silicone having a shore A durometer of about <NUM> to about <NUM>, more preferably in the <NUM> - <NUM> range, may also provide improved sealing characteristics against water ingress and allow for less stringent assembly tolerances (e.g., assembly of the light guide <NUM> within the pocket <NUM>). The light guide <NUM> may completely surround the optical sensor <NUM> (e.g., side surfaces and top surface). The light guide <NUM> may be inserted or positioned within the pocket <NUM> such that a top surface <NUM> is flush with the top surface <NUM> of the coupler <NUM>. In certain embodiments, the optical sensor <NUM> may be recessed (e.g., by about <NUM> to about <NUM>). A small recess or flush surface may help to accommodate tolerance variations or to prevent any ambient light from reaching the optical sensor when the cartridge <NUM> is mounted to the coupler <NUM>.

Referring back to <FIG> and with additional reference to <FIG>, the personal care appliance <NUM> may include a digital counter <NUM> that can be reset. <FIG> illustrates a block diagram is shown depicting one possible embodiment of a method of resetting a digital counter <NUM>. The digital counter <NUM> may generate usage data about the personal care appliance <NUM> (<FIG>), such as count time (e.g., shaving duration), incidence of usage, or strokes (e.g., shaving strokes). The optical sensor <NUM> may send the electrical output signal to the control circuit <NUM>. The control circuit <NUM> may then compare the electrical output signal to the first predetermined threshold value stored in the control circuit <NUM>. In certain embodiments, the first predetermined value for the electrical output signal may correspond to an irradiation of the optical sensor <NUM> of about <NUM> mW/m<NUM> or to an illumination of about <NUM> lux. In other embodiments, the first predetermined value may correspond to <NUM> mW/m<NUM> or <NUM> lux. If the electrical output signal is below these values, the cartridge <NUM> may be attached to the coupler <NUM>. The consumer user interface <NUM> may display the status of the cartridge <NUM> (e.g., displaying words and/or a cartridge symbol). It is understood the consumer user interface <NUM> may be positioned somewhere on the handle <NUM> of <FIG>; however, in lieu of or in addition to, a smart device <NUM> (e.g., computer, tablet, phone or watch) may also be provided with consumer user interface.

When the cartridge <NUM> is removed, the electrical output signal will be greater than or equal to the first predetermined value. Accordingly, the control circuit <NUM> may send a signal to the consumer user interface <NUM> on the handle <NUM> and/or the smart device <NUM> prompting a consumer to input a response, noting the cartridge <NUM> has been removed from the coupler <NUM>. The consumer user interface <NUM> and/or the smart device <NUM> may then send a signal resetting the digital counter <NUM>. Alternatively, the control circuit may bypass the consumer interface <NUM> and reset the shave stroke counter. However, this may not be advantageous, as the digital counter <NUM> may be reset without the consumer's knowledge when the cartridge <NUM> is reattached after it was accidentally detached (e.g., during a drop). The consumer user interface <NUM> and/or smart device <NUM> allows the user to confirm the status of the cartridge <NUM>.

The control circuit <NUM> comparing the electrical output signal to the predetermined value may work for a wide range of ambient light conditions. However, it may be possible for such a system to confuse the attachment condition of the cartridge <NUM> in very bright light conditions where the control circuit <NUM> sends a signal that the cartridge is attached, but in reality, it is not. Accordingly, the control circuit <NUM> may in lieu of or in addition to, may detect a change in the electrical output signal over time to compensate for such conditions. The time variable may be determined by the approximate amount of time it takes to detach the cartridge <NUM> from the coupler <NUM> plus the time to attach the cartridge <NUM> to the coupler <NUM>.

If the control circuit detects a drop in the electrical output signal over time, then the control circuit <NUM> may send a signal to the consumer user interface <NUM> and/or the smart device <NUM> prompting a consumer to input a response, noting the cartridge <NUM> has been removed from the coupler <NUM>. The consumer user interface <NUM> and/or the smart device <NUM> may then send a signal to reset a digital counter <NUM>. The amount of the change in the electrical output signal over time may also be stored by the control circuit <NUM> (e.g., as a second predetermined value).

Referring to <FIG>, a block diagram is shown depicting another possible embodiment of a method of resetting the digital counter <NUM>. As previously described for the embodiment disclosed in <FIG>, the optical sensor <NUM> may send an electrical output signal to the control circuit <NUM>. The control circuit <NUM> may then send a signal to the cloud <NUM>. The cloud <NUM> may use an algorithm to process the signal from the control circuit <NUM> along with additional (e.g., usage information provided by the consumer and/or the control circuit <NUM>). The cloud <NUM> may then send a signal to the consumer user inter face <NUM> and/or the smart device <NUM> notifying the user and requesting confirmation. The consumer may provide an input to the consumer user inter face <NUM> and/or the smart device <NUM> to reset the digital counter <NUM>.

Referring to <FIG>, <FIG> and <FIG> the consumer user interface <NUM> of the handle <NUM> of the personal care appliance <NUM> may display one or more notifications to the user. For example, the consumer user interface <NUM> may display a cartridge removal notification <NUM>, such as an icon, informing the user that the cartridge <NUM> has been removed, as shown in <FIG>. The consumer user interface <NUM> may display a cartridge attachment notification <NUM>, such as an icon, informing the user that the cartridge <NUM> is successfully attached and is ready for use. The consumer user interface <NUM> may change the display from the cartridge attachment notification <NUM> to the cartridge removal notification <NUM> based on the input from the control circuit <NUM> (<FIG>) or the cloud <NUM> (<FIG>). When the cartridge <NUM> is reattached or replaced with a new cartridge <NUM>, the consumer user interface may display an input request notification <NUM> of a cartridge replacement condition, such as an icon, requesting confirmation from the user that the cartridge <NUM> has been replaced. If the consumer inputs the cartridge <NUM> has been replaced, a signal may be sent to reset the digital counter (<FIG>).

Claim 1:
A personal care appliance (<NUM>) comprising:
a handle (<NUM>) having a coupler (<NUM>) at a first end (<NUM>);
a control circuit (<NUM>) positioned within the handle;
a consumer user interface (<NUM>) operably connected to the control circuit;
a digital counter (<NUM>) operably connected to the control circuit;
an optical sensor (<NUM>) mounted to the coupler that is configured to send an electrical output signal to the control circuit,
a cartridge (<NUM>) configured to be removably mounted to the coupler, the cartridge having an opaque surface (<NUM>) covering the optical sensor and blocking ambient light from reaching the optical sensor when mounted to the coupler, wherein the control circuit is configured to determine an attachment status of the cartridge by comparing the electrical output signal to one or more predetermined thresholds or by detecting a change over time in the electrical output signal from the optical sensor.