Discrete-amount fluid-dispensing system for a personal care device

The fluid-dispensing system is used in a personal care appliance, such as a power toothbrush. The dispensing system includes a strip of discrete, fluid-containing packets, a compressible sealing member and a hollow needle for puncturing the packets, the hollow needle being connected to a workpiece such as a brushhead via a connecting line. An actuation assembly includes a piston which moves successive packets against the sealing member, initially sealing the packet thereto. Further pressure results in compression of the sealing member and puncturing of the packet by the needle, with fluid being forced by piston pressure from the packet into the hollow needle and then to the connecting line for delivery to the workpiece.

This invention relates generally to fluid-dispensing personal care appliances, such as for example, power toothbrushes, and more specifically concerns such a system in which fluid is dispensed in discrete, known amounts.

Fluid-dispensing personal care appliances of various kinds and configurations are generally well known. For instance, many toothbrushes are known which include a fluid-dispensing structure. The particular fluid will vary, depending upon the application. It can, for example, be an oral care fluid such as a dentifrice or oral medication, or a lotion for the skin. Most fluid-dispensing systems use a pump, with the user dispensing fluid through a mechanical action, although automatic fluid-dispensing devices are also known. In some arrangements, a piston or similar element is positioned within a reservoir to move fluid into a connecting line which extends to the workpiece element. In other arrangements, a peristaltic-type pump arrangement is used, in which a roller or other mechanism is operative to squeeze fluid out of a cartridge, without direct contact with the fluid. In still other arrangements, the action of the workpiece itself moves fluid from a reservoir to the workpiece.

However, many of these known fluid-dispensing devices have significant disadvantages. These disadvantages include difficulty in maintaining the various elements of the system, including in particular the pump structure itself, clean and operative. Occasionally, the fittings or other portions of the pump will dry out and/or the fluid will partially dry in the pump or the line between the pump and the workpiece, preventing proper operation until the system has been cleaned. Further, many of the known fluid-dispensing mechanisms are quite complex, and in many cases quite expensive relative to the cost of the toothbrush. Most of such fluid-dispensing devices are not reliable, particularly for long-term operation. In addition, the amount of fluid pumped can vary significantly and proper sealing of the pump system is often complex and difficult to reliably achieve.

Hence, while a fluid-dispensing capability for personal care appliances, such as a power toothbrush, is certainly known to be beneficial, very few if any such devices have been successful, even though there have been a large number of attempts.

In some cases, it is important that only a very specific amount of fluid, typically a medication, should be dispensed for a particular use event. Existing devices, as indicated above, typically do not have a high accuracy in dispensing a selected volume of fluid.

Further, it is sometimes desirable to dispense two or more medications which cannot be mixed together in a reservoir in a single use event with the medications being in prescribed, preselected amounts. To the best of applicant's knowledge, there are no currently known systems having such a capability.

Hence, it is desirable that a fluid-dispensing structure for personal care appliances have the capability of reliably dispensing discrete amounts of fluid, and also have the capability of dispensing two or more fluids at the same time to the area of interest, such as the mouth, while maintaining the fluids separate prior to dispensing.

Accordingly, the present invention in one aspect is a discrete-amount fluid-dispensing system for a personal care device, comprising: a personal care appliance having a workpiece member, such as a power toothbrush; a strip that includes a successive plurality of discrete fluid-containing packets; a compressible sealing member against which each packet on the strip may be sealed in succession; a hollow needle structure for puncturing the packets as each packet is moved in front of the needle in succession; and an actuation assembly for moving the strip against the sealing member, sealing each packet in turn against the sealing member and then compressing the sealing member, exposing the needle so that the packet is punctured by the needle, wherein continued pressure by the actuation assembly forces the fluid in the packet through the needle into a connecting line to the workpiece member.

Another aspect of the invention is a discreet-amount fluid-dispensing system for a personal care device, comprising: a personal care appliance having a workpiece member; a strip that includes a successive plurality of discrete fluid-containing packets; a needle structure on the workpiece member for puncturing the packets in succession as the strip is moved in front of the needle structure and pressure applied to the strip against the needle structure, wherein the fluid in the punctured packet thereafter flows to the vicinity of the workpiece member; and a guide structure in the appliance for holding and guiding the strip along the appliance to the vicinity of the workpiece member and then out of the appliance.

The basic structure of the present invention is shown inFIGS. 1-4, in the context of a power toothbrush application. The power toothbrush is shown generally at10, comprising a handle portion12and a removable head portion14. The head portion includes an elongated arm16, at the end of which is a moving brushhead18. Brushhead18is actuated by a driving unit20, located in handle12. The driving assembly can have a variety of configurations and arrangements, including but not limited to an electromagnetic actuator or a DC motor. Other arrangements can be used.

The driving unit20can be powered by an internal battery or from the wall. WhileFIG. 1shows a power toothbrush application, it should be understood that the fluid-dispensing system of the present invention can be used in other personal care appliances. These include, for example, a shaver, a power face cleaner/brush, a hot wax hair remover, a fluid-dispensing back brush and a fluid-dispensing hair brush, among others.

The fluid-dispensing system of the present invention includes a strip or web25of individual packets or blisters26-26on a carrier element28. Carrier element28is of flexible material, currently referred to as form, fill and seal packaging, such as triophane, polypropylene or fibrous web, and includes perforation lines30-30between each successive packet26. Fluid is contained within packets26. “Fluid” is intended herein to be a broad term, including a variety of substances, having a range of viscosities, including gels. Fluid will include dentifrices and medications, as well as various lotions.

The type of fluid will vary in accordance with the particular application. It can be a conventional dentifrice, for instance, for a power toothbrush application, or particular medications useful in the oral cavity for the treatment of gum disease or other oral disease. The particular fluid can be such as to aid the action of the device, such as fluid which assists in the shaving process, or which soothes the skin for other skin-related applications. Strip25, in the embodiment shown, shows successive rows of two side-by-side packets26. The packets, for instance, could contain two or more different medications which cannot be mixed together in a single reservoir or in a single packet, but which need to be dispensed for the same treatment event. Typically, however, each row will include only a single packet.

The strip25of packets will typically be folded in a serpentine arrangement and into a cartridge34, such as shown inFIG. 3or rolled into a round package. A start feed tab36extends out the front end38of cartridge34. Near the rear end of strip25, a visual marker27can be provided which indicates that the end of the strip is near.

FIGS. 4,5and6show the details of the fluid-dispensing system of the present invention, again for a power toothbrush application for ease and clarity of explanation. The power toothbrush38includes a handle portion39and a separate, removable head portion40. A drive shaft42for a brushhead (not shown) is driven by a driving unit44assembly which is an electromagnetic driver in the embodiment shown, operating on magnets45at the rear end of drive shaft assembly42. Such structure is described in detail in U.S. Pat. No. 5,189,751. A cartridge46containing a strip/web47of fluid-containing packets is shown in a cartridge-receiving portion48. To access the cartridge-receiving portion48, a panel50on the handle is lifted up and rotated about hinge52.

In use of the appliance, a cartridge46is inserted into the handle and a forward tab portion57of strip47is pulled out of the cartridge46sufficiently that a first packet54in the strip is positioned against a sealing member56located at the rear of head portion40. Sealing member56is a hollow cylinder, typically made out of a compressible, resilient material, such as rubber or plastic backed by a spring. The sealing member56in the embodiment shown has an outside diameter of approximately 0.3 inches and an inside diameter of approximately 0.1 inches, and is approximately 0.3 inches high. A hollow needle58is mounted to extend through the center of the sealing member. The hollow needle is connected to a fluid line59which extends to the workpiece (not shown), such as a brushhead.

The fluid-dispensing assembly38also includes an actuation assembly60. Actuation assembly60includes a piston element62having a front face64which is in substantial registry with a rear face of sealing member56. Extending rearwardly from piston element62is a control element66which has an upper surface68which is curved to match a user's thumb. Control element66extends slightly above the exterior surface of panel50, which has an opening therein to accommodate the control element and its forward movement.

Actuation assembly60is mounted within the toothbrush for movement in the direction of the sealing member56by action on the control element66. Forward movement of the actuation assembly is accomplished by the pressure of a user's thumb on the control element in the forward direction. When the user releases the thumb pressure, a return spring72returns the actuation assembly to its rear position within handle34.

FIGS. 7,8and9show the steps in dispensing fluid by means of the system shown and described.FIG. 7shows a single fluid-filled packet76positioned between sealing member78and piston80. In this position, there is usually a small space between forward surface81of piston80and packet76, as well as a space between packet76and rear surface83of sealing member78. Hollow needle82, which extends through the center of sealing member78, is angled and sharpened at its tip84in order to facilitate puncture of packet76. The center portion of the sealing member78has a scooped-out region86, into which tip84of the needle extends, but not beyond surface83when the sealing member is in its relaxed condition (FIG. 7).

When the user pushes forward on the control member66(FIG. 5) to the extent shown inFIG. 8, packet76is compressed between sealing member78and piston80. When packet76initially makes contact with sealing member78, a fluid-tight seal is accomplished therebetween. Sealing member78compresses, such that stationary needle82extends beyond surface83of the sealing member, penetrating packet76, which is also compressed.

FIG. 9shows packet76fully compressed, with substantially all of the fluid in the packet having been forced out of the packet by the action of the piston, into needle82and, from there through the connecting line and to the workpiece. The individual components in the system are shaped and arranged so that the packet is substantially completely emptied once the packet has been punctured and pressure has been maintained for a suitable period of time, allowing the sealing member to expand into space formerly occupied by the packet with fluid.

After dispensing has been completed, the pressure on the thumb actuated control element66is released, the sealing member returns to its original configuration, and the actuation assembly60returns to its rear position.

In the embodiment shown, a single needle has been described and shown for puncturing a single packet. A single connecting line connects the needle with the workpiece. In the embodiment where two packets are side-by-side in each successive row (FIG. 2), two adjacent needles are used, which puncture the individual packets simultaneously. The two needles will connect to connecting lines, which could be joined early, forming a single connecting line, or there could be two separate connecting lines up to the workpiece. Alternatively, multiple packets could be dispensed in a short sequence. Two successive actuation actions could be used to dispense the two (or more) fluids to the workpiece.

Hence, the present structure provides for the simultaneous dispensing, if desired, of two or more fluids which are not compatible for storage in a single reservoir. This is advantageous for those situations where more than one fluid must be provided to the user in the course of a single treatment event.

FIGS. 5 and 6show a structure for advancing the strip of packets after each use. A drive wheel90is mounted for rotation on an axle91on the actuation assembly. The drive wheel90includes cogs93which extend out from the periphery of the drive wheel90and are designed to engage the surface of the strip of packets between successive packets as the drive wheel is rotated. Mounted on drive wheel90is a sprocket member94which mates with a rack element96of the actuation assembly. Drive wheel90includes a one-way clutch which allows it to move only in a clockwise motion. As the actuation assembly is moved forward, compressing the packet against the sealing member56, the rack96engages the sprocket member94, but there is no rotation of the drive wheel. On the return of the actuation assembly, drive wheel90is engaged by the clutch and turns, engaging the packet strip with cogs93, bringing the next packet into position between the piston and the sealing member and moving the depleted packet out of the appliance.

Each depleted packet, in turn, as it comes outside of the appliance, is removed at a perforation line between the depleted packet and the packet now in position for dispensing. Alternatively, the depleted packets can be accumulated in a cartridge or the like.

Hence, a fluid such as a dentifrice can be accurately dispensed in discrete, known amounts, because the amount of fluid in each packet is controlled and hence known, as successive packets are brought into position between the piston and the sealing member. The creation of a seal between the packet and the sealing member prior to puncture results in a clean delivery of fluid, with fluid in the packet going through the needle to the workpiece, and without any fluid escaping between the sealing member and the packet being emptied. The mechanical structure shown and described results in a reliable puncturing and dispensing action for an extended number of uses. The actuation assembly also includes a spring structure returning the actuation assembly to its rear (rest) position after dispensing of the fluid in one packet has been accomplished. During the return time, a drive mechanism is activated to bring the next packet into position between the piston and the sealing member. A motor could be used to automatically move the strip, compress the packet and sealing member with the piston and dispense the fluid.

In a variation of the above embodiment, individual separate fluid-containing packets (not associated with a strip) could be loaded by a user into a chamber which contains structure similar to that described above to seal, puncture and deliver the fluid from the individual packet to a workpiece, such as a brushhead.

FIGS. 10a-10dshow one alternative embodiment to the system ofFIGS. 1-9. The fluid is stored in packets106on prefabricated foil strips110, with hot seals107between the packets. Foil strip110is inserted into a guide portion111of the toothbrush. As shown inFIG. 10(c), the strip110extends through a front part113, i.e. head portion, of the brush, up to the brushhead114, and then reverses direction rearwardly 180° at the brushhead. The strip continues to the rear and then out of the toothbrush near the front end of the handle.

To move or transport the strip110simply requires the user to pull to the rear on the exposed strip, moving the strip in the direction of the arrow. Depleted packets may be removed by the means of tearing the strip at perforations, cutting or any other means, between successive packets. The brushhead114includes a needle or sharp edge117, past which the strip extends. Placing pressure on the strip in this vicinity results in a puncture of the packet and forcing of the dentifrice through an opening118in the brushhead base into the bristles of the toothbrush. Again, as in the other embodiments, fluid is dispensed in discrete amounts contained in individual packets on a transporting strip. The amount in each packet is known.

FIG. 11shows another embodiment, in which a toothbrush120includes a cartridge121, which is mounted to a rear surface122of the toothbrush, extending from handle123to brushhead124. Brushhead124has a central opening125which is in registry with an opening127in cartridge121at a forward end thereof. A plurality of individual tablets129-129is provided in the cartridge, spring-loaded by means of a spring131. Spring131pushes the tablets to the forward end of the cartridge. The apparatus includes a dispensing actuator133, which is mechanically arranged so that operation of the actuator, such as by a downward action on portion135thereof, presses the tablet at the forward end of the cartridge through opening127in the cartridge and opening125in the brushhead. The tablet moves by gravity through the brushhead into the mouth of the user. Again, the dentifrice/medication in the tablet is dispensed individually in discrete, known amounts. In this embodiment, the separate tablets are arranged sequentially and are separate, i.e. they are not joined by a transport web.

Accordingly, a fluid-dispensing system has been disclosed in which known amounts of fluid are dispensed for a given treatment event. Control is maintained over the amount of fluid provided to the user. Sterility is also maintained, both with sterile packets and the use of a sealing member during dispensing of the fluid. The cartridge containing the strip of packets can be easily removed and inserted into an appliance by opening a cover portion in the appliance handle. Dispensing the individual discrete amounts of fluid can be either manual, such as by a user, or can be automatic with a motor of some kind. Further, multiple packets can be arranged in a single row on the strip, providing more than one fluid/medication to be dispensed for one treatment event. High control is thus maintained over the dispensing of fluid with the arrangement shown.

As indicated above, the fluid-dispensing system can be used in a variety of personal care hygiene devices, including power toothbrushes, electric shavers and other devices mentioned above.

In a variation of the fluid-containing packet strip described above, a strip may be divided into individual portions where each strip portion is consumable in its entirety. A dentifrice/medication may comprise the individual portions or may be contained in each portion with the strip portion being consumable in addition to the fluid-medication container therein. In such an arrangement, shown inFIG. 14, there is no remaining strip element or depleted package to be thrown away. The fully ingestible element could be in the form of a strip135or a rod, or other form, in a toothbrush137from which pieces of known dentifrice/medication amounts are cut and used/dispensed. The individual sections can be presented manually to the user as shown, or can be directed to the vicinity of the brushhead138.

FIGS. 12 and 13show another embodiment of the present invention, in which a fluid dispensing system using fluid-filled discrete packets on a strip, with the packets having a known quantity of fluid therein, is separate from the appliance, which could for instance be a toothbrush. In this embodiment the fluid dispensing system comprises a separate unit140, as opposed to being a part of the appliance. It could also be part of a charging unit for the appliance.

The unit140includes an opening141to receive a workpiece portion, such as a brushhead142of a power toothrbush appliance. A strip146of fluid-filled packets is positioned in a slot148in unit140, above opening141. A plunger149is located above strip146. Positioned below the strip is a needle154. When brushhead142is inserted into opening141, it engages a spring158which through a lever160activates the plunger149forcing a packet161located beneath the plunger down against the needle154. The plunger could also be activated by a knob153or by a small motor. The fluid in the punctured packet falls through an opening in the unit onto brush142. When the plunger149is released by removal of the brushhead, lever162and associated cam164transports the strip by one packet for the next dispensing event. The depleted packet moves out of unit140. As with the other embodiments, there may be more than one fluid dispensed for a particular event, such as with the use of multiple packets.

Although a preferred embodiment of the invention has been described for purposes of illustration, it should be understood that various changes, modification and substitutions may be incorporated in the embodiment without departing from the spirit of the invention which is defined in the claims which follow.