Patent Publication Number: US-2015078799-A1

Title: Inductively-heated applicator system

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to applicators for health and beauty products, and more particularly to applicators for applying health and beauty products in a heated state. 
     A wide variety of serums, salves and other health and beauty products are available for topical application. In some applications, these products are applied simply by hand. With many products, however, an applicator is available to assist the user in applying the product. 
     Applicators are available in a variety of different types. Simple applicators may utilize a brush or foam pad to apply the product. In some applications, the applicator may be more complex and may include a reservoir for the product. One conventional applicator includes a rolling ball for applying the product. In a typical rolling ball applicator, the rolling ball is positioned in the neck of a product reservoir with a portion exposed on the exterior of the applicator. As the rolling ball is rolled within the neck, it draws product out from the reservoir. 
     In some applications, it is desirable to heat the product prior to application. With some products, heat improves effectiveness, or simply provides a more pleasant product application experience. 
     SUMMARY OF THE INVENTION 
     The present invention provides an inductively-heated applicator system for applying heated serums, salves and other health and beauty products. The applicator generally includes a heating module and an applicator. The heating module includes circuitry, including a primary, for generating electromagnetic waves and the applicator includes a heating element that can be heated directly or indirectly by electromagnetic waves generated by the primary. In operation, the heating module heats the applicator inductively without wires or other direct electrical connections between the heating module and the applicator. 
     In one embodiment, the applicator includes a heating element that is directly inductively heated (i.e. the heating element is manufactured from a material that heats sufficiently in the presence of electromagnetic waves). In an alternative embodiment, the applicator may include a secondary that inductively receives power from the primary of the heating module, and the induced power may be used to heat the heating element. For example, the heating element may be a resistive element that is heated by the application of electrical current. 
     In one embodiment, the applicator includes a roller element for applying a serum, salve or other health and beauty products. The roller element may be manufactured from a material that heats in the presence of electromagnetic waves. In an alternative embodiment, a portion of the applicator tip is manufactured from a material that heats in the presence of electromagnetic waves. In another alternative embodiment, the roller element is partially enclosed in an isolator to thermally isolate and remove the roller element from the flow path of the product. A retainer may also assist in directing the flow path of the product. 
     In one embodiment, the heating module includes a dock to removably receive the applicator. For example, the applicator may be snap-fitted or frictionally fit into the dock. As another example, the applicator and heating module may include one or more magnets to retain the applicator in the dock. In one embodiment, the applicator includes a roller element and the dock is configured to retain the applicator with the roller element in the approximate center of the primary. 
     In one embodiment, the system includes temperature monitoring circuitry for controlling operation of the system based on temperature. For example, the heating module may stop generating electromagnetic waves when the application reaches a specific temperature. The temperature monitoring circuitry may be incorporated into the heating module and may provide temperature monitoring of the applicator. In one embodiment, the heating module may include a temperature sensor in physical contact with the application when the applicator is docked. The temperature sensor may be in direct engagement with the roller element. In an alternative embodiment, temperature monitoring circuitry may be included in the applicator and wireles sly communicate with the heating module. 
     In one embodiment, the system includes a capsule storage base. The capsule storage base may plug into the heating module to store a capsule of product for use with the applicator. 
     The present invention provides an inductively-heated applicator system that permits application of heated serums, salves and other health and beauty products to localized areas of a person&#39;s body. The system includes an applicator that is heated without wires or other direct electrical connections. Among other things, this simplifies use and operation of the applicator. Some products degrade faster once they have been heated. In some embodiments, heating of the product in the applicator is minimized in favor of heating either the product once it is external to the applicator or heating the area of interest to prepare the area to better respond to the product. Heat may also increase the rate at which some products are absorbed into the body and provide a warm sensation that can be more appealing than an experience with a room temperature applicator. 
     These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the current embodiment and the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an inductively heated applicator system in accordance with an embodiment of the present invention. 
         FIG. 2  is an exploded perspective view of the system showing the applicator pen removed from the heating module. 
         FIG. 3  is a sectional view of the system showing the applicator pen docked in the heating module. 
         FIG. 4  is an exploded view of an applicator pen in accordance with an embodiment of the present invention. 
         FIG. 5  is a sectional view of the applicator pen. 
         FIG. 6  is a sectional close-up view of the applicator pen tip in a closed state. 
         FIG. 7  is a sectional close-up view of the applicator pen tip in an open state. 
         FIG. 8  is a sectional close-up view of an alternative embodiment of an applicator pen tip. 
         FIG. 9  is a perspective view of one embodiment of the retainer. 
         FIG. 10A  is a first portion of the schematic diagram of one embodiment of the control system. 
         FIG. 10B  is a second portion of the schematic diagram of one embodiment of the control system. 
         FIG. 11  is a flowchart of one embodiment of the control algorithm of the control system. 
         FIG. 12  is one embodiment of the block diagram of the inductively heated applicator system. 
         FIG. 13  is an alternative embodiment of the block diagram of the inductively heated applicator system. 
     
    
    
     DESCRIPTION OF THE CURRENT EMBODIMENT 
     An inductively-heated applicator system in accordance with an embodiment of the present invention is shown in  FIGS. 1-3 . The applicator system  10  generally includes a heating module  12  and an applicator  14 . The heating module  12  includes circuitry  16  for generating a varying electromagnetic field. The circuitry  16  may include a primary  18  for generating the electromagnetic field. The heating module  12  may also include a dock  43  for removably retaining the applicator  14  in the presence of the electromagnetic field. The heating module  12  may include a magnet  44 , or other retaining mechanism to assist in retaining the applicator  14 . The applicator  14  includes a dispensing system, an applicator system and a heating element  22 . The heating element  22  may be independent or part of the dispensing or applicator system. In the illustrated embodiment, the heating element  22  is a roller element that is inductively heated when positioned within the electromagnetic field. In an alternative embodiment the heating element  22  may be conductive tip  86  attached to the end of the applicator  14 , as shown in  FIG. 8 . The applicator system  12  may include temperature monitoring circuitry for monitoring the heating element  22  and providing feedback to the applicator system  10  to control the temperature of the heating element  22 . 
     The heating module  12  of the illustrated embodiment is configured to plug into and be supported by a power outlet, such as a standard 110V receptacle. The heating module  12  may be configured to receive power from other power sources, including other types of power outlets, such as European standard 220V outlet. The heating module  12  can be designed to be supported by essentially any type of power outlet. Alternatively, the heating module may be supported independently of the power outlet. For example, the heating module may be a freestanding unit with a power cord that plugs into a power outlet. 
     In the illustrated embodiment, the heating module  12  generally includes circuitry  16 , a dock  43 , a housing  23  and a plug  24 . The heating module circuitry  16  controls operation of the applicator system  10 . Perhaps as best shown in the  FIG. 12  block diagram, the heating module circuitry  16  generally includes a main power supply subcircuit  30 , a tank subcircuit  32 , a temperature monitoring subcircuit  34  and a controller  36 . In the embodiment illustrated in  FIGS. 10A and 10B , the controller  36  is a digital signal controller, such as the 44-Pin dsPIC30F2023 Enhanced Flash SMPS 16-Bit Digital Signal Controller available from Microchip Technology Inc. of Chandler, Ariz. The controller  36  is programmed to control operation of the system  10 , and may access external supplemental memory  38 , such as 24AA64/SOIC EEPROM. The controller  36  may also include internal memory (not shown). The controller  36  may also include an external clock oscillator  40 , if desired. 
     In the illustrated embodiment, the main power supply subcircuit  30  generally includes a rectifier  100 , a driver  102  and a pair of switches  104   a - b . The rectifier  100  converts incoming AC power to DC power. In the illustrated embodiment, the rectifier  100  receives 120V AC input power via jumper  106 . Jumper  106  may be connected to a wall outlet or other source of 120V AC power. The output of the rectifier  100  is connected to the switches  104   a - b . A capacitor, such as capacitor  105  in the illustrated embodiment, may be used as a shunt for high frequency noise in the rectified signal. In the illustrated embodiment, the switches  104   a - b  are FETs, such as FDS2672, 200V N-Channel UltraFETs Trench MOSFETs, which are available from Fairchild Semiconductor of South Portland, Me. In this embodiment, the driver  102  is a half-bridge driver, such as the L6384 high-voltage half bridge driver available from STMicroelectronics of Geneva, Switzerland. The driver  102  controls the timing of the FETs  104   a - b  to generate a high-frequency AC signal in the tank subcircuit  32 . The main power supply subcircuit  30  may also include an “overtemp” input that is coupled to a temperature sensor (described below) to disable the half-bridge driver  102  if the applicator exceeds a maximum temperature. The main power supply subcircuit  30  may also include a “coil0_L” input that is coupled to the controller  36  to provide instructions to the driver  102 . 
     In the illustrated embodiment, the tank subcircuit  32  is a series resonant tank subcircuit, however, the illustrated tank subcircuit  32  may be replaced by other suitable tank subcircuits. The tank subcircuit  32  generally includes a capacitor  108  and a primary  110 . The value of capacitor  108  may vary from application to application, for example, to adjust the resonant frequency of the tank subcircuit  32 . The primary  110  may be a coil of wire (e.g. Litz wire) or other circuit component capable of generating a suitable electromagnetic field in response to the power supplied to the tank subcircuit  32 . For example, the primary  110  may be a printed circuit board coil in accordance with U.S. Ser. No. 60/975,953, which is entitled “Printed Circuit Board Coil” and filed on Sep. 28, 2007 by Baarman et al, and which is incorporated herein by reference in its entirety. 
     In the illustrated embodiment, the circuitry  16  also includes separate operating power supplies to provide operating power for various circuit components. As shown in  FIG. 10A , operating power supply subcircuit  112  generates approximately 15V DC to provide power for logic, FET drivers and other circuit components that operate on 15V DC. Referring again to  FIG. 10A , operating power supply subcircuit  114  generates approximately 5V DC to provide power for microprocessors, op amps and other circuit components that operate on 5V DC. Additional or fewer power supplies may be included in alternative embodiments. 
     In the illustrated embodiment, the circuitry  16  also includes a current sensor subcircuit  116 . The current sensor subcircuit  116  may be used to determine if the applicator  14 , or a foreign object, is present. The current sense subcircuit  116  may also be used for diagnostics. In alternative embodiments the current sense subcircuit  116  may be used to facilitate additional features. For example, the heating module circuitry  16  may include the resonant seeking circuit of the inductive power supply system disclosed in U.S. Pat. No. 6,825,620, which is entitled “Inductively Coupled Ballast Circuit” and issued Nov. 30, 2004, to Kuennen et al; the adaptive inductive power supply of U.S. Pat. No. 7,212,414, which is entitled “Adaptive Inductive Power Supply” and issued May 1, 2007, to Baarman; the inductive power supply with communication of U.S. Ser. No. 10/689,148, which is entitled “Adaptive Inductive Power Supply with Communication” and filed on Oct. 20, 2003 to Baarman; the inductive power supply for wirelessly charging a LI-ION battery of U.S. Ser. No. 11/855,710, which is entitled “System and Method for Charging a Battery” and filed on Sep. 14, 2007 by Baarman; the inductive power supply with device identification of U.S. Ser. No. 11/965,085, which is entitled “Inductive Power Supply with Device Identification” and filed on Dec. 27, 2007 by Baarman et al; or the inductive power supply with duty cycle control of U.S. Ser. No. 61/019,411, which is entitled “Inductive Power Supply with Duty Cycle Control” and filed on Jan. 7, 2008 by Baarman--all of which are incorporated herein by reference in their entirety. 
     The circuitry  16  may include a temperature monitoring subcircuit  34  having one or more temperature sensors to control the applicator  14  temperature. In the illustrated embodiment, temperature sensor  130  provides the controller  36  with a signal indicative of the temperature of the applicator  14  for temperature control purposes and an over-temperature sensor  133  to shut down the half-bridge driver  102  if the applicator  14  exceeds a maximum temperature. The temperature sensor  130  may be a temperature-to-voltage converter, such as the TC1047A available from Microchip Technology Inc. The output of the temperature sensor  130  may be connected to the controller  36  through buffer  134 . The buffer  134  assists in providing sufficient current for the analog to digital conversion of the temperature sensor reading. The over-temperature sensor  133  may be a temperature switch, such as the TC6501 ultra small temperature switch available from Microchip Technology Inc. The over-temperature sensor  133  is connected to the driver  102  to disable the driver  102  if the maximum temperature is exceeded. Additional, different or less temperature monitoring circuitry may be included in alternative embodiments. 
     The circuitry  16  may also include an iRdA communication subcircuit  150  to provide wireless communications with the controller  36  when desired. The wireless communication subcircuit  150  can be used for diagnostics, programming and other functions. 
     The circuitry  16  may include a voltage sensor subcircuit  118 . In the illustrated embodiment, the voltage sensor subcircuit  118  is used for diagnostic purposes. In alternative embodiments, the voltage sensor subcircuit  118  may be deleted or used for other purposes. 
     As noted above, the circuitry  16  may include memory  38 . The memory  38  may be used to save applicator system parameters or other information. Memory  38  may be provided on the controller  36  or elsewhere in circuitry  16 . 
     The circuitry  16  may also include user input and LED driver circuitry  120 . In the illustrated embodiment, the user input is a simple on/off switch. In other embodiments, the user input may provide more sophisticated control. For example, the user input could be a dial capable of adjusting the temperature range of the applicator  14 . The LED driver circuitry may be used to indicate the status of the applicator system  10 . In one embodiment, blinking lights indicate that the applicator  14  is currently being heated, a solid light indicates that the applicator  14  has reached temperature and fast blinking indicates a fault condition. In the illustrated embodiment there are two primary fault conditions, either the applicator  14  is missing or an over temperature condition occurred. In alternative embodiments there may be different LED schemes and different fault conditions. In other embodiments, other user interface features may replace or supplement the LEDs. For example, audio or other types of feedback may be used to indicate a fault or ready condition. 
     As noted above, the circuitry  16  may include an external clock oscillator  40 . The external clock oscillator  40  may be a more accurate clock for use in controlling the timing of the FETs  104   a - b  in the power supply circuit  30 . In alternative embodiments the controller  36  may use an internal clock to control the FET timing. 
     The circuitry  16  may include power conditioning circuitry  126 . The power conditioning circuitry  126  in the illustrated embodiment may be used to reset the processor. 
     The housing  23  is designed to contain the circuitry  16 . In the illustrated embodiment, the housing  23  includes a base  26  and a cover  28 , perhaps best shown in  FIG. 2 . The base  26  supports and contains the main portion of the circuitry  16 . The cover  28  closes the base  26  and houses the primary  18 . In this embodiment, the cover  28  is shaped to define a dock  43 . For example, the cover  28  may include a cowl  40  that encloses the primary  18  and defines a central opening  42  to permit the applicator pen  14  to be inserted into the dock  43  and into the center of the primary  18 . The cover  28  may include a magnet  44  to removably retain the applicator  14 . The magnet  44  may be positioned to interact with the roller element  22  to secure the applicator  14 . Alternative applicator retention mechanisms, such as snap-fitting or frictional fitting, may be used instead of or in addition to magnet  44 . The switch and LEDs  25  integrated with housing  23  may interface with the user interface and LED driver circuitry  120  to provide user control and status feedback to the user as described above. In alternative embodiments, the switch and LEDs may be deleted or replaced with suitable alternative components. 
     The present invention is suitable for use with a wide variety of types and styles of applicators. Perhaps best shown in  FIG. 12 , the applicator  14  generally includes a dispenser system  19 , an applicator system  21  and a heating element  22 . In the illustrated embodiment, the applicator  14  is an applicator pen with a plunger and check valve system to force product of the applicator and a roller element  54  to apply the product. Further, in the current embodiment, the roller element  54  also acts as a heating element. Other applicators may include additional, different or fewer components. The dispenser system  19  may be replaced with essentially any system or combination of systems capable of dispensing product. For example, the dispensing system  19  may be a plunger system, spring system, vacuum system or threading system. Alternatively, the dispenser system  19  may be inherent in the applicator configuration, for example, shaking or squeezing the applicator may enable suitable dispensing of product from the applicator. These examples of dispenser systems are merely exemplary, essentially any suitable dispenser system may be integrated into the applicator  14 . The applicator system  21  may be replaced with essentially any system or combination of systems capable of applying product. For example, the applicator system may include a roller element  54 , such as a roller ball or roller cylinder. The applicator system may include a heating element  22 . In some embodiments, the roller element may also be a heating element. In some embodiments, an applicator system, such as a roller element, may also be a sufficient dispenser system to extract product from the applicator. In some embodiments, a roller element may be the dispenser system, the applicator system and the heating element. 
     In the embodiment illustrated in  FIGS. 3-7 , the applicator pen generally includes a stem  50 , a body  66  and a cap  78 . The stem  50  is an elongated element that defines an interior space  53  to receive the body  66 . The stem  50  may also house a dispenser system for creating pressure within the interior space  53  to assist in dispensing product. In the illustrated embodiment, the dispenser system includes a plunger  52 , an umbrella valve  76 , a pump piston  56 , a pump spring  58 , a fixture  60  a check valve  62 , a pump piston  64  and an applicator check valve assembly (described below). An air cavity  51  is defined between the pump piston  56  and the plunger  52 . The body  66  of the illustrated embodiment is generally tubular defining an interior space  67  that houses product or product capsules. The body  66  may also house a product piston  64  for pressurizing the interior space  67 . The cap  78  is an elongated element that receives body  66  and helps define interior space  67 . The cap  78  generally includes an applicator system in the form of a roller element  54 . In the illustrated embodiment, the roller element  54  is also part of the applicator check valve assembly of the dispenser system. The applicator check valve assembly generally includes a spring  68 , a retainer  70 , an isolator  72 ,  74  and a rolling element  54 . 
     In operation, the applicator  14  is primed by depressing the plunger  52 , which in turn pushes the pump piston  56  creating air pressure within interior space  53 . Air pressure is equalized within interior space  53  thorough check valve  62  and into interior space  67  that contains the product. As air pressure is applied to the product piston  64 , the piston  64  applies pressure to the product, which is maintained by check valve  62 . With pressure applied to the product, product will be dispensed when the roller element  54  is depressed against the skin to create an external flow path. 
     The plunger  52  may be primed numerous times. The maximum air pressure may be controlled by the umbrella valve  76  set point. The umbrella valve also allows for new air to enter interior space  53  on the return stroke created by the pump spring  58 . That is, on the return stroke, a vacuum is created in interior space  53 , which pulls air from cavity  51  through the umbrella valve  56 . There is an air flow path between cavity  51  and external the applicator. In the illustrated embodiment, an air flow path exists between the plunger  52  and the stem  50 . The dispense cycle may be repeated as desired or based on a particular application dosage. The dose amount may be controlled by adjustment of the maximum pressure allowed by the pressure system, or by other means. In some embodiments this could be user adjustable. 
     The spring  68  is biased such that the applicator  14  defaults to a closed state, as shown in  FIG. 6 . Applying a sufficient amount of external pressure on the roller element  54  causes the spring  68  to depress to an open position, illustrated in  FIG. 7 . In the open position, a flow path from interior space  67  to outside the applicator  14  is created via gap  79 . If the applicator  14  is sufficiently primed, product will dispense through gap  79 . Gap  79  may be a ring, slots or any other type of opening that allows product to be dispensed out of the applicator  14 . The roller element  54  may be used to distribute the dispensed product as the user sees fit. 
     In the embodiment illustrated in  FIGS. 3-7 , the roller element  54  functions as the heating element. The roller element  54  may be manufactured from essentially any material capable of being inductively heated in the presence of an electromagnetic field. For example, the roller element may be manufactured from metal, compounds of metal and organics or ceramics, or plastic with metal mixed. The roller element  54  may also be manufactured from a material selected based on the desired heat capacity. For example, some or all of the roller element may be manufactured using a material with relatively high heat capacity, such as ceramic. In alternative embodiments, where the roller element is not a heating element, the roller element may be manufactured from essentially any suitable material. In some embodiments, the roller element  54  may be textured to increase or control the thickness, or other characteristics, of the applied product. 
     Some or all of the temperature monitoring circuitry  34  is positioned near or in contact with the roller element  54 . In operation, the controller  36  controls operation of the heating module  12  in response to the output of the temperature monitoring circuitry  34 , for example, by engaging and disengaging the main power supply subcircuit  30  to maintain the roller element  54  at the desired temperature. If the roller element  54  exceeds the maximum temperature, the over-temperature sensor  133  may bypass the controller  36  and shut off the driver  102 . 
     As noted above, the embodiment illustrated in  FIGS. 3-7  includes an isolator  72 ,  74  and retainer  70 . In the illustrated embodiment, the isolator internally isolates the roller element  54  from the flow path of the product and thermally isolates the roller element from the product. The isolator may be manufactured as one or multiple pieces. In the embodiment illustrated in  FIGS. 3-7  the isolator includes a first portion  74  and a second portion  72 . In embodiments where the roller element  54  is also a heating element, the isolator assists in minimizing the amount of heat transferred to product within the applicator  14 . Although heated product may be desired at the time of application, it may be undesired at other times because it can increase the rate at which the product degrades. Therefore, in some applications it is desirable to minimize the amount of heat transferred to the product inside the applicator  14 . To further assist in minimizing heat, protrusions  80  may be included on the internal surface of the isolator to minimize the direct contact between the roller element  54  and the walls of the isolator  72 ,  74 . Further, the protrusions may also enable the roller element  54  to roll more easily in the isolator  72 ,  74 . 
     In embodiments that include an isolator, the retainer  70  may be configured to assist in both retaining the roller element in position and creating a flow path around the isolator. A perspective view of the retainer of the embodiment described in  FIGS. 3-7  is shown in  FIG. 9 . The retainer  70  includes a generally cylinder portion  75  that includes a roller interface portion  71 . Together, the cylinder portion  75  and the roller interface portion  71  define a number of holes  73  where product can flow. In alternative constructions of the retainer  70 , the roller interface portion is solid and the cylinder portion  70  includes a number of holes that allow product to flow past the retainer  70 . In some embodiments, such as the embodiment shown in  FIGS. 1-2 , a retainer  70  may be unnecessary and may be deleted. In other embodiments, such as the  FIG. 8  embodiment described below, the retainer may include a hole in the roller interface portion  71  that allows the roller element  54  direct access to the product in interior space  67 . 
     An alternative applicator  14  tip is illustrated in  FIG. 8 . In this embodiment, the roller element  88  need not be a heating element because conductive tip  86  is made from material that may be heated in the presence of an electromagnetic field. The roller element  88  may be made from plastic or other non-conductive material. As with the  FIGS. 3-7  embodiment, this embodiment minimizes the heat transfer to product internal to the applicator  14 . As mentioned above, because there is no isolator in this embodiment, the product may flow directly from the interior space  67  onto the roller element  88 . The retainer  82  may be configured to allow fluid communication between interior space  67  and roller element  88 . 
     In the embodiments described above, the inductively-heated applicator system  10  includes an applicator  14  that is essentially passive in the sense that it includes no electronics and the heating element  22  is heated inductively. In an alternative embodiment, the applicator may include a resistive heating element and the circuitry required to apply power to the resistive heating element. For example, in the alternative system illustrated in  FIG. 13 , the heating module  212  generates an electromagnetic field that the applicator  214  converts to power with secondary circuit  223  in order to apply power to heating element  222 . The applicator system  221  and dispenser system  219  may be essentially any systems suitable for applying and dispensing product. The controller  236  may be essentially any controller suitable for controlling the heating module. Optional charge storage  225  may be included on the applicator. The charge storage  225  may be a rechargeable battery so that the pen may be heated even while removed from the heating module. The charge storage  225  may hold a sufficient amount of charge in order to maintain a selected temperature of the heating element. In the  FIG. 13  embodiment, the temperature monitoring subcircuit  234  resides on the applicator instead of the heating module as described above. The temperature monitoring subcircuit  234  may monitor the heating element temperature and provide protection by disconnecting power to the heating element  222  if a threshold temperature is exceeded. In some embodiments, the temperature monitoring subcircuit  234  may wirelessly communicate with the wireless communication subcircuit  250  in order to shut off the main power supply subcircuit or provide other functionality. 
     In the embodiments described above, the applicator  14  has been described in connection with a roller element. In alternative embodiments, the roller element may be replaced with another application mechanism. Further, the shape of the applicator has been illustrated and described as an applicator pen. The size, shape and configuration of the applicator may vary from application to application. In one embodiment, the applicator is shaped to match a specific body part, such as a user&#39;s shoulders or knees. 
     The system  10  may be configured to heat the applicator to essentially any desired temperature. In the illustrated embodiment, the system  10  is configured to apply between  0 . 5  amps and  1 . 5  amps of current to the primary. In this embodiment, the system  10  is configured to apply product at temperature between  35 C and  45 C. 
     Exemplary operation of the system  10  is described in connection with the flowchart illustrated in  FIG. 11 . Once the heating module plug is inserted into the wall  122 , the heating module enters standby mode  131 . A determination is made in the heating module of whether sufficient AC power is available  124 . If sufficient power is available, an LED indicator is turned on to indicate standby mode  126 . A determination of the state of the on/off power button is made  128 . If the power button is off, the system remains in standby mode  131  until the button is pressed. If the power button is on, a determination about the presence of the applicator is made  130 . If the applicator is present heating mode  132  is entered. If the applicator is not present, the system enters pen fault handling mode  152 . 
     In heating mode  132 , the applicator temperature is measured  134 . The current applicator temperature is compared to a threshold temperature  136 . If the current applicator temperature is above the threshold then the system enters steady state mode  144 . If the current applicator temperature is below the threshold then the heating process is started and the LED indicator is changed to reflect that the applicator is being heated  138 . Another temperature measurement is taken and compared to the threshold temperature  140 . If the current applicator temperature is below the threshold temperature then the system checks if the pen is present  142 . If the applicator is still present then a check is made to see if a timeout has occurred  145 . If a timeout has occurred then the applicator is turned off  164  and enters standby mode  131 . If a timeout has not occurred then the applicator continues to heat until the temperature reaches the set temperature  140 . If the applicator is not present, the applicator fault handling state  152  is entered. If the current applicator temperature is above the threshold temperature then steady state mode  144  is entered. 
     In steady state mode  144 , the heating process is halted  143  and an LED is changed to indicate that the applicator is ready for use  146 . An applicator temperature measurement is made and compared to an acceptable temperature range  148 . If the current applicator temperature has fallen below the acceptable temperature range then the heating process  138  is started again. If the temperature is within the acceptable temperature range then a determination is made of whether the applicator is present  150 . If the applicator is not present the applicator fault handling state  152  is entered. If the applicator is present, a comparison between the elapsed time in steady state mode  144  and a threshold is made  162 . If the elapsed time is below the threshold then the temperature is measured and compared to the acceptable temperature range again  148 . If the elapsed time is greater than the threshold the applicator system is turned off  164  and the system enters standby mode  131 . 
     In the applicator fault handling state  152 , an LED is changed to a flashing state  154 . A determination of whether the applicator is present is made  156 . If the applicator is present then the system returns to the previous operational state  160 . If the applicator is not present then a determination of whether time has expired is made  158 . If time has not expired, presence of the applicator is checked  156 . If time has expired, the applicator is turned off  164 . 
     Reference to various timeouts is made throughout the exemplary heating module flowchart, in some applications, these timeouts may refer to a single master timeout condition, in other applications, each timeout condition may exist separately and be based on any number of suitable factors. For example, the amount of time waiting in steady state mode  162  before shutting off may be the same or different from the amount of time waiting in heating mode  132  before entering the pen fault handling state  152 . 
     There may be hysteresis in the heating module control system. From the steady state mode  131 , the temperature of the applicator may drop some number of degrees below the set point before the heating mode  132  is entered. In other embodiments, there may be a number of intermediate heating states in which the heating parameters are changed to allow a slower approach to the set point temperature. 
     The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular.