Tampon saturation monitoring system

A tampon that has a sensor and a signal line that peripherally connects the sensor with a peripheral signal processor. The sensor provides a blood wetting signal in response to a progressing blood saturation boundary in the tampon. The signal may be resistive, capacitive or optic. The simple sensor has two proximal signal terminals separated by a fluid responsive medium in wetting communication with the tampon's body. The tampon may be removed by use of the signal line. From signal timing and/or signal gradient the processor may predict when the tampon needs to be changed.

FIELD OF INVENTION

The present invention relates to systems and devices for monitoring the menstrual blood saturation progress in vaginally inserted tampons.

BACKGROUND OF INVENTION

Tampons are conveniently used by women to absorb menstrual blood. For that purpose a tampon is commonly vaginally inserted. The tampon acts as a fluid absorption body that seals the vaginal channel and at the same time absorbs menstrual blood from the uterus until the tampon reaches its fluid absorption limit. If the tampon is not replaced at that time, menstrual blood may leak out of the tampon.

For a woman it may be difficult to predict when the tampon has reached its fluid absorption limit. Therefore, there exists a need for a system for monitoring the saturation progress of a vaginally inserted tampon. The present invention addresses this need.

During the menstrual period a large number of tampons may be needed and replaced in short time intervals. Therefore, there exists a need for a tampon saturation monitoring system that utilizes simple and inexpensive yet reliable sensor configurations. The present invention also addresses this need.

There exists also a need for a tampon user to receive a preemptive forecast when a tampon in use may reach its fluid saturation limit. The present invention also addresses this need.

SUMMARY OF INVENTION

A tampon saturation monitoring system of the present invention features a tampon that has a saturation sensor positioned inside the fluid absorption body and a first signal line that peripherally connects the saturation sensor with a peripheral signal processor. The fluid saturation sensor provides a wetting response signal in conjunction with a blood saturation boundary that is axially progressing along the fluid absorption body.

The saturation sensor is a simple device including at least two proximal signal terminals separated by a fluid responsive medium that is preferably made of the same gauze material as the fluid absorption body is fabricated from. The two proximal signal terminals have a signal potential across the fluid responsive medium, which is in wetting communication with the fluid absorption body. The saturation sensor may be configured to provide a resistive, capacitive or optic wetting response signal, which the processor analyzes to derive information of the saturation boundary progress of the fluid absorption body. The processed saturation information is passed on to a saturation notifier, which may be a buzzer, a tactile notifier in skin contact or a software application installed on a portable multifunction device.

The processor may also compute from signal timing and/or signal gradient a forecast of the moment when the tampon will reach its full saturation. In that way, a tampon user may conveniently plan ahead to timely replace the inserted tampon.

The first signal line may be a cable that is structurally combined with the fluid absorption body such that the tampon may be pulled from its vaginally inserted position by use of the cable. The cable may feature a connector to easily connect and/or disconnect to the processor. The processor may be configured as a disposable device with a battery life corresponding to a predetermined number of tampons and this processor may be packaged together in each box of tampons. The processor may also be configured as a standalone unit with a replaceable battery.

DETAILED DESCRIPTION

Referring toFIGS. 1-4, a tampon saturation monitoring system10includes a tampon11, a signal processor14and a notifier15. The tampon11has a well known fluid absorption body111as commonly used in commercially available tampons, a saturation sensor120and a first signal line114, which is preferably a cable. The fluid absorption body111extends along a saturation progress axis11X. The fluid absorption body111has a fluid access end112and a peripheral end113opposite to the fluid access end112in the direction of the saturation progress axis11X. When the tampon11is positioned in the vaginal channel1, menstrual blood from the uterus is mainly absorbed by the fluid absorption body111in the vicinity of the fluid access end112and axially progresses substantially in a direction along the saturation progress axis11X. The more blood is absorbed, the further the blood saturation boundary2progresses towards the peripheral end113.

Should the blood saturation boundary2reach the peripheral end113, blood may seep out of the tampon11as may be well appreciated by anyone skilled in the art. To prevent this from happening and to give the tampon11user sufficiently early warning, the saturation sensor120is positioned axially with respect to the saturation progress axis11X generally in between the fluid access end112and the peripheral end113, preferably in close proximity to the peripheral end113. The saturation sensor120preferably includes two proximal signal terminals121A,121B having a signal potential across a fluid responsive medium122that separates the signal terminals121A,121B.

The fluid responsive medium122is in a wetting communication with the fluid absorption body111. This means that as the saturation boundary2axially progresses past the saturation sensor120, the menstrual blood following the saturation boundary2is wetting the fluid responsive medium122.

As the saturation boundary2penetrates the fluid responsive medium122, a wetting response signal S is generated in conjunction with the axially progressing saturation boundary2. The wetting response signal is generated when the signal potential between the two proximal signal terminals121A,121B is activated by a change of physical properties in the fluid responsive medium122due to the wetting. The physical properties change may include a change of electric resistance, dimensional spacing, light attenuation, and/or light filtering as explained in more detail in the below.

In a particular case in which the saturation sensor120extends substantially axially along the saturation progress axis11X as depicted in theFIGS. 1-5, the wetting communication may be radially and axially responsive to the saturation boundary2while progressing in between the frontal end124and the rear end125of the saturation sensor120. In that case, the wetting response signal S may be gradual and in a proportion to the axially progressing saturation boundary2in the radial vicinity of the saturation sensor120in between its frontal end rear ends124,125. From the gradual wetting response signal S, the processor14, and/or the notifier15may provide a tampon11full forecast, which may include a time span until the tampon11reaches its fluid absorption limit and optionally an forecast error margin. A forecast error margin may consider fluctuations in the axial progression of the saturation boundary2as may well occur due to a varying level menstrual bleeding.

In embodiments in which the wetting response signal S is a resistive signal occurring between two proximal signal terminals121A,121B configured as electrical conductors, any stray current flow from the proximal signal terminals121A,121B to the vaginal lining1may need to be kept below a well established body leakage current maximum as is well known to anyone skilled in the art. According to the well known Ohm's law, a current flow for a given conductivity is proportional to the voltage difference along the conductive path. Hence, the voltage difference between the proximal signal terminals121A,121B may be selected sufficiently low and independently of a processing voltage of the processor14. The processing voltage may be a voltage required by the logic circuitry inside the processor14. The voltage difference between the signal terminals121A,121B may be a fraction of the processing voltage and selected in conjunction with a predetermined conductivity between at least one of the signal terminals121A,121B and the proximal vaginal lining1and the maximum allowed body leakage current. At the time the invention was made, the maximum allowed body leakage current known to the inventor is 10 microampere. The processor14may feature a processing circuitry146that operates at the processing voltage and a low voltage circuitry145that provides the voltage difference at a fraction of the processing voltage.

The present invention includes embodiments with more than two signal terminals121A,121B which may be radially spread across a cross section of the tampon11to capture eventual axial progress fluctuations of the saturation boundary2. In such a case, the wetting response signal S may be summed and averaged by the processor14and/or balanced within the saturation sensor120by grouping and conductively connecting the number of proximal signal terminals121A,121B in two sets.

The first signal line114peripherally connects the saturation sensor120across the peripheral end113with the signal processor14preferably via a connector115. The signal processor14computes the progress of the saturation boundary2from the wetting response signal S. The notifier15, which is in communication with the signal processor14notifies the tampon user about the progress of the saturation boundary2.

In a first embodiment of the invention, the at least two proximal signal terminals121A,121B are electric conductors. The physical property change of the fluid responsive medium122due to menstrual blood wetting may be an electric resistance change. The wetting response signal S may occur in between the electric conductors121A,121B and across the fluid responsive medium122in conjunction with electric resistance change and a voltage difference between the two electric conductors121A,121B. The voltage difference may be applied by the processor14via the connector115and the cable114.

The electric resistance change may result from the menstrual blood that is wetting the fluid responsive medium122. Blood has a well known conductivity due to its iron content as is well known in the art. The fluid responsive medium122may be configured with a dry conductivity that substantially differs from the blood's conductivity to provide the electric resistance change in conjunction with its blood wetting. As depicted inFIG. 2, one of the electric conductors121A may be an enveloping conductor121A encapsulating the second electric conductor121B and acting as an electric ground. As a result, eventual electric current flow due the electric resistance change may be contained within the enveloping conductor121A irrespective of an eventual outside conductive path of the absorbed blood outside the saturation sensor120. The outside conductive path may be related to the wetting communication of the fluid responsive medium122with the fluid absorption body111.

The wetting communication across the enveloping conductor121A may be implemented by configuring the enveloping conductor as a fluid permeable material such a metal mesh, metal weaving and/or perforated metal foil. In case of a coaxial cable employed as the first signal line114, the enveloping conductor121A may be an integral conductive part of the coaxial cable's114shielding mesh. A shielding mesh may be the well known part of a coaxial cable114circumferentially protruding along the cable114to electrically and/or magnetically shield core wires against the surrounding environment as is well known in the art.

The first signal line114is preferably a cable114such as an optic fiber cable or an electric cable such as an unshielded strand cable or a coaxial cable as described above. The cable114may be structurally combined with the fluid absorption body111such that the tampon11may be pulled out of its vaginally inserted position1via said cable114. In the preferred case in which the fluid absorption body111is made of rolled up gauze as is well known in the art, the cable114may be knotted with the gauze at the peripheral end113. In that way, tensile stress during the removal of the tampon11is conveniently transferred from the cable114onto the fluid absorption body111via the knot118. At the same time, the knot118may serve to transfer eventual cable114stress during tampon11use onto the fluid absorption body111such that the saturation sensor120remains free of cable114stress at a constant position within the fluid absorption body111. The constant position may assist in providing a more accurate tampon full forecast.

At least one of the proximal signal terminals121A,121B may be integral part of a strand of the cable114. In case of an optic cable114, the strand may be an optic fiber. In case of an electric cable114, the strand may be an electric wire strand or as described above a shielding mesh. As depicted inFIG. 5, the strands of the proximal signal terminals121A,121B may be separated and spaced from each other by a number of spacers117that are axially arrayed with respect to the saturation progress axis11X. The cable114may feature a well known surrounding insulation1141and the spacer(s)117may be of that surrounding insulation117. In that way, the saturation sensor120may be simply fabricated from the cable114by separating a number of spacers117from the surrounding insulation1141in such a way that their encapsulating structural integrity remains intact. The cable114strands may be exposed to the fluid responsive medium122, by sliding the separated spacers117along the strands. In that way constant spacing between the proximal signal terminals121A,121B is achieved in a simple fashion during fabrication.

The fluid responsive medium122may be integral part of the fluid absorption body111. In the preferred case of the fluid absorption body111being made of a well known gauze material, the saturation sensor120may be fabricated by interweaving separated proximal signal terminals121A,121B with the gauze material and/or rolling them up together with gauze material such that the proximal signal terminals121A,121B are preferably at a central location of the fully fabricated tampon11. The knot118may be fabricated prior to rolling up the gauze material.

Referring toFIG. 6, the proximal signal terminals121A,121B and the fluid responsive medium122may together a capacitor. The wetting response signal S may be an electric capacitance change of the saturation sensor120. The electric capacitance change may result from a wetted swelling of the fluid responsive medium. The wetted swelling may occur as the fluid responsive medium absorbs menstrual blood. The wetted swelling may push the proximal signal terminals121A,121B further apart, which reduces the capacitance between the proximal signal terminals121A,121B according to the well known principles of an electric capacitor. The proximal signal terminals121A,121B may be interweaved rolled up, perforated, metal foils separated by the fluid responsive medium122. The metal foils121A,121B perforation may provide for the wetting communication across metal foils121A,121B. The fluid responsive medium122may again be from the same gauze material as the fluid absorption body111. The perforated metal foils121A,121B may be rolled up together with the fluid absorption body111, making the tampon11fabrication very simple and inexpensive. In addition, the metal foils121A may feature an insulating coating such that no electric current flow will occur inside the fluid absorption body111irrespective of the eventual presence of conductive blood.

Referring toFIG. 3, the saturation sensor120may be an optical bridge featuring a light emitter121A proximal to a light receiver121B. The separating fluid responsive medium122may be optically responsive. The wetting response signal S may be a light attenuation change and/or a light spectrum change of the fluid responsive medium122in response to the blood wetting of the fluid responsive medium122. At least one but preferably both light emitter121A and light receiver121B may be integral optic fiber strands of the cable114extending into the saturation sensor120. The fluid responsive medium122may be of a gauze material of a thickness and optic permeability suitable for attaining the desired optic responsiveness as may be well appreciated by anyone skilled in the art.

The processor14may feature a light source141and a light sensor142optically connected to the cable114via connector115. The light source141pumps light across the connector115and through the cable114into the fiber end121A, which may be stripped off its reflective coating and/or otherwise processed in a well known fashion such that the light may emerge laterally from the exposed fiber end121A. The light receiver fiber121B may also be processed in a well known fashion such that some of the light emitted from the emitting fiber121A and passing through the fluid responsive medium122is caught in the receiving fiber end121B and transmitted via the fiber optic cable114and across the connector115back to the light sensor142.

According toFIG. 4, light emitter121A and light receiver121B may be combined in conjunction with a well known optic gate143in the processor14. The optic gate143redirects the returning light beam towards the light sensor142while switching through the light from the light source141towards the saturation sensor120. In such a single signal terminal121configuration, the fluid responsive medium122may be reflectively optically responsive such that light emitted from the single signal terminal121is back reflected while attenuated and/or spectral changed. The reflection may be diffuse in case of a conventional gauze material utilized as the fluid responsive medium122. As a favorable result, the single fiber saturation sensor120is highly consistent in its wetting response signal S strength since there are no spacing fluctuations between emitter and receiver that eventually reduce signal precision and repeatability.

The notifier15may be an acoustic notifier such as a buzzer. Acoustic notification may vary in tone, loudness, and/or time interval to provide a distinguishable information to the user about the tampon's11saturation boundary2progress. The notifier15may also be a tactile notifier such as a vibrating element configured for skin transmitted vibration notification. The notifier15may be structurally separated from the processor14and in wireless communication with the processor14via a second signal line119(FIG. 1). In that way, the processor may be carried conveniently attached to undergarment in proximity to the tampon11whereas the notifier15may be positioned at a location suitable for communication to and/or with the tampon11wearer.

The notifier15may be a software application installed on a portable multifunction device such as but not limited to a cellular phone or a handheld computing device. At the time of this invention, portable multifunction devices include features such as wireless communication capabilities well known under the term Bluetooth™ that are suitable for communicating with peripheral devices such as the processor14. Upon installation of the notifier15software, the portable multifunction device may provide, visual, acoustic or other well known notification via its built in hardware features.

Referring toFIG. 7, an embodiment of the invention features the fluid responsive medium122as integral part of the fluid absorption body111, which may be of a gauze material coiled into a cylindrical shape. InFIG. 7, an intermediate fabrication stage of the tampon11is schematically depicted at which the gauze material111/122may be still in uncoiled condition. The first signal line114in the preferred configuration of a cable may be sewed on the gauze material111/122via seams16such that operational tampon11may be pulled out of the vaginally inserted position1via the cable114. Sewing may be particularly suitable since it provides for an axially straight integration of the cable114inside the fluid absorption body111, which assists the coiling of the gauze material111/122around saturation progress axis11X as may be well appreciated by anyone skilled in the art. Optionally, the backwards bending signal terminal(s)121A,121B may also be sewn on to the gauze material111/122.

Separation and spacing between signal terminals121A,121B may be provided by the gauze material111/122. This may be accomplished by having one signal terminal121backwards through an optional hole1113in the gauze material111/122. The signal terminal121A is depicted inFIG. 7in dashed lines to indicate it being on the backside of the gauze material111/122.

At least one but preferably all proximal signal terminals121A,121B are preferably an integral part of the cable114and backwards and extending from the sewn on portion of the cable114such that the signal terminal ends1213A,1213B are in immediate proximity to the peripheral end113. As a favorable result, the progress of the blood saturation boundary2may be monitored closest to the peripheral end113such that a user of the tampon saturation monitoring system10may be notified with highest precision until the very moment the tampon11reaches its fluid absorption limit. The cable signal terminals121A,121B may be composed of thin wire strands held together by the spacers117.

The signal processor14may be a simple micro controller. Its circuitry may be configured and/or programmed to reset during disconnection or connection of a connector115indicating a tampon11change. Referring toFIG. 8and upon connection of the connector115with the processor14at T0, the saturation sensor120may be tested as is well known in the art. A calibration signal S0may be received from the processor14during initial testing. The moment T0of initial connection may be recorded by the processor14as well as a second moment T1of the initial receipt of the wetting response signal S1. Second moment T1occurs when the saturation boundary2has progressed so far as to reach the frontal end of the saturation sensor120. In the case of a saturation sensor120configuration that provides a gradual and proportional wetting response signal S as described above, the wetting response signal S may increase in amplitude as the saturation boundary2progresses axially along the saturation sensor120. This is reflected in the graph ofFIG. 8by the inclining portion of the curve2C within the boundaries of the saturation sensor120.

The processor14may time an initial signal delay DTO between the first moment T0and second moment T1. In case of an estimated progression behavior of the saturation boundary2as depicted by the curve2C inFIG. 8, the processor14may process the tampon11full forecast DTF1from the initial signal delay DTO and from an initial amplitude of the wetting response signal S1. Any wetting response signals at and below the testing amplitude S0may be disregarded by the processor14and signal processing may initiate with the initial measurement at T1at which the signal amplitude is above the testing signal S0amplitude.

Additional measurements may be performed by the processor14in time intervals DTX and the tampon11full forecast DTF2may be computationally updated. Signal amplitude of the wetting response signal S2may be in a difference DS to the initial wetting response signal S1in case of a saturation sensor120with gradually and proportional wetting response signal as described above.

The more measurements that are performed the more accurate the tampon11full forecast DTF1, or DTF2may be computed and the error margin for the tampon11full moment TN brought to a minimum. A user of the tampon saturation monitoring system10can monitor the saturation progress of the tampon11with a precision that increases as the tampon11reaches its fluid absorption limit at which the wetting response signal SN may have a maximum amplitude.

The interval measurements T1, T2, TN provide for a minimum battery consumption and consequently a miniature configuration of the processor14. The battery life of the processor14may correspond to a predetermined time of use of a number of tampons11packaged together with the processor14in a set.

After vaginally inserting the tampon11, the connector115may be connected with the processor14and the saturation sensor120may be initially tested and the connection moment T0eventually recorded. The processor14may be activated but its signal processing remains dormant until an initial measurement T1with an initial signal amplitude S1that exceeds test signal amplitude S0is recognized by the processor14. At the moment T1, the processor's14computing capacity may be activated and a notification initially passed on to the user via the notifier15. The user's attention is brought to an upcoming tampon11change and the user can conveniently plan ahead to timely change the tampon11without worrying of missing the tampon's11fluid absorption limit.

Accordingly the scope of the present invention described in the figures and the specification above is set forth by the following claims and their legal equivalent: