Patent Document

BACKGROUND OF THE INVENTION 
     Modern sauna compartments are often heated by an infrared heater which is controlled by a thermostat. The thermostat will be set at a maximum temperature such as 120° Fahrenheit. When that temperature is reached, the thermostat interrupts the flow of energy to the heater which is then energized. A person in the sauna immediately feels chilled when the infrared is completely turned off at the 120° Fahrenheit maximum temperature level. 
     Therefore, a principal object of the present invention is to provide a method and means of heating a sauna compartment and controlling the heat so that the heat is more evenly supplied. 
     A further object of the invention is to provide a programmable sauna control for setting the temperature of a sauna. 
     These and other objects will be apparent to those skilled in the art. 
     BRIEF SUMMARY OF THE INVENTION 
     A control panel for a sauna compartment and a power unit associated with the control panel that allows high voltage to flow through multiple heating elements. The control panel contains a plurality of buttons that are electrically connected to a computer chip that contains software for signaling the power unit that controls the heating of the sauna. The control software includes a pulse width modulator output for causing the heating elements to emit variable power settings of heat to provide a constant and continuous heating experience. The control panel contains lighting and a plurality of displays that provide information such as a real time clock temperature and a timer. Additionally, the software is programmed to store information regarding the operation of the sauna. The power unit also contains a chip having software that is in communication with the chip in the control panel and controls the operation of the heating elements on the power unit. The heating elements are controlled by the pulse width modulations scheme operated by the power unit processor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         FIG. 1  is a perspective view of a sauna compartment having a control panel; 
         FIG. 2  is a schematic diagram of a control panel including a microprocessor; 
         FIG. 3  is a schematic diagram of displays and backlighting used on a control panel; 
         FIG. 4  is a schematic diagram of a speaker system used on a control panel; 
         FIG. 5  is a schematic diagram of a power unit of a sauna including a microprocessor and non-volatile memory chip; 
         FIG. 6  is a schematic diagram of electrical control devices of a power unit of a sauna; 
         FIG. 7  is a schematic diagram of electrical control devices of a power unit of a sauna; and 
         FIG. 8  is a schematic diagram of a power supply of a power unit of a sauna. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A sauna compartment  10  has door opening  12  and door  14  adapted to close the opening  12 . A control panel  16  is mounted in the wall of compartment  10  adjacent the door as shown in  FIG. 1 . The control panel  16  has a plurality of openings  18  thereon with days of the week adjacent each opening and additionally has a plurality of windows or displays  20  for displaying digital images such as real time clock, temperature, and timer. The control panel or interface  16  additionally has a plurality of buttons  22  that control the functioning of the control panel  16  and sauna compartment  10 . 
     As seen in  FIGS. 2-4  the control panel or interface  16  is a complex circuit that causes the desired functioning of the control panel  16 . Specifically, the control panel  16  internally has the plurality of buttons  22  that are electrically connected to a microprocessor  30 . Microprocessor  30  contains a software program that controls the operation of the control panel  16  and the sauna  10 . A non-volatile memory chip is employed to save a program even when power of the control panel  16  is discontinued. Furthermore, the software provides a seven day programmable timer for seven day operation of the sauna  10  having a static memory so programs are not lost when the power goes out. The software loads automatically upon being turned on. The software also causes digital outputs in the displays  20 . Other features of the software includes temperature readouts in F/C, real time clock, high temperature limit cut off with manual reset, and the like. The microprocessor controls are adaptable and expandable to additional programmable functions. 
     Electrically connected and operably controlled by the microprocessor  30  are a plurality of operating systems that include the digital output of displays  20 , the lighting of the openings  18  by LEDs  32  (light emitting diodes) and backlighting  34  of the control panel  16 . The backlighting  34  consists of a plurality of LEDs  36  that provide backlighting so that the digital outputs of the displays  20  are seen by an observer. The software in the microprocessor  30  is programmed to backlight a logo from left to right. Furthermore, the LEDs  32  and  36  alternatively are different colors depending upon the application. Thus, when a button  22  is compressed, the button electrically communicates with the chip  30  that sends a signal to one of the displays  20 , or light emitting diodes  32  or  36  consistent with this signal. A unique feature of the control panel function is the use of time division multiplexing used to operate the LED display elements. Additionally control panels  16  can be serially connected together, allowing for control of the sauna from multiple locations. 
     Also electrically and operably connected to the microprocessor  30  is another control system that is a speaker system  38  that comprises a pair of operational amplifiers  40  that are connected to a speaker  42  such that the circuit allows not only audio but also a beeping noise to be made depending on the button  22  that is pressed. 
       FIGS. 5-8  show the power unit  50  of the sauna  10 . The power unit  50  has its own microprocessor  52  that communicates with the microprocessor  30  of the control panel  16 . Like the microprocessor  30  of the control panel  16 , the microprocessor  52  of the power unit  50 , has software that controls the functions of the items on the power unit  50 . Additionally, the microprocessor  52  has a pulse width modulator or square wave output such that a pulse width modulation output is sent to the elements within the power unit  50 . 
     Operably and electrically connected to the microprocessor  52  are a plurality of optical isolated drivers  58 . The isolators  58  are comprised of a plurality of triacs  60  that are associated with AC receptacles  62 . By using a pulse width modular output, or wave function, the heat produced by the heating element (not shown) when attached to the receptacle  62  is intermittent and variable, and thus the heat produced by the attached heating elements is output in waves of different intensity that correspond with the pulse width modulation. Thus the software of the control panel  16  controls the pulse width modulation output to drive the triacs  60 . Therefore, an operator of the sauna feels a constant heat from the heating element. Thus, a five level heater control with gentle balance and constant emission is achieved. 
     Connected to the isolators  58  is a heat sink  66  for dissipating heat generated by current flowing through the isolators  58  to provide maximum efficiency and increase the life span of the system and components. The power unit  50  also has a receptacle dedicated to providing power to an interior 120 vac light with an adjustable dimmer, which is activated from the control panel  16 , and receptacle for temperature probe  74 , used for keeping an accurate and consistent temperature within the sauna  10 . The temperature probe is accurate to 1° C. Preferably the temperature probe is accurate within 1° C. The light switch and the temperature probe are both logically and electrically connected to the microprocessor  52 . Using information from the temperature probe  74  the microprocessor  52  intelligently operates the triacs  60  to produce a desired heating output controlling each heater separately. Therefore by mounting the triacs  60  on the heat sink  66  and intelligently operating the triacs  60 , hot spots on the heat sink  66  are minimized. Thus five levels of intensity for precise adjustments are used for the heating elements and dimmer control for the 120 vac light. 
     The power unit  50  has a plurality of receptacles  62  such that multiple heaters are attached to a single power unit  50 . 
     Some of the benefits of the newly designed system include the single function button switches  22  for easy operation and quick access. Additionally, audio signals with a speaker system are utilized when the buttons  22  are activated giving the user an audible feedback assuring that the button function is activated. 
     The present circuit design also allows for a plurality of functions by the control panel  16 . For example, when the control panel  16  is plugged in, the unit is in standby mode. At this time the logo backlight  34  is turned on going left from right lighting the logo. Additionally, the clock display, temp display with a current temperature, and the Sunday LED  36  are simultaneously turned on. Next, the clock is set by pressing the up or down button  22  adjacent the clock display  20  to set the current time. The display also shows A.M. and P.M. indicator LEDs. 
     Next, the current date is set: the scroll down button is pressed until the LED  32  is activated next to the adjacent day. Similarly, the temperature set and timer set buttons  22  create similar results. When the unit is in operating mode the temp display  20  shows the actual temperature inside the sauna  10 . When an operator pushes the up or down button  22  beside the temp display or the operating mode, the set temperature is displayed and is changed. Then the actual temperature is displayed five seconds after the last adjustment is made. 
     In one embodiment the software in the microprocessor  30  is programmed to control each triac  60  individually in order to incrementally control each individual heating unit. In this embodiment each heating unit has sixteen varying levels that are incrementally controlled by the power received from the triacs  60  that are controlled by the microprocessor  30 . Thus, with an extremely accurate temperature probe  74  the precise level of heat each heating unit must produce in order to maintain the temperature at a constant rate is controlled by the triacs  60 . 
     As an additional option, in one embodiment the software is able to cycle the power provided to each heater. For example only, when four heaters are present, in a first cycle the first heater remains deactivated while the second, third and fourth heaters produce heat. Then a millisecond later, in a second cycle the first, third and fourth heaters produce heat while the second heater is deactivated, etc. This allows the heater to be heated by drawing less current than is previously required because at all times only three out of the four heaters is drawing power. Nonetheless, because the microprocessor varies the sixteen levels at which heat is provided, the proper temperature is maintained. 
     Alternatively, additional features and functions include that only one program per day is possible. Specifically, when in the program mode an LED  32  is lit for each day where a program is entered. When the control panel  16  is turned on, if a program has not been set, the control panel defaults and the last program used loads automatically. To change the program for that day the set button  22  is pressed until that day is selected. Pushing the set button  22  when the clock, temp, or timer displays  20  are flashing erases that days program and the day LED  36  begins flashing thus, reverting back to the first step of the programming for the day. Likewise, pushing the on/off button  22  when the clock, temp, or timer displays  20  are flashing erases that day&#39;s program, and switches the unit into standby mode. Thus the program has predetermined cycles and time settings. 
     Using the quick start method overrides a program set for that day but does not alter the program or erase it. The program only operates from the standby mode. When the unit is manually turned on using the quick start method, the programs are not active. Thus, depending on which buttons  22  are pressed, different signals are sent to the microprocessor  30  of the control panel  16  causing predetermined functions and results to occur. The combination of the control panel  16  and power unit  50  allows a user to set programs for the sauna  10  including lengths of time the heat is to be produced, when the heat is produced and the temperatures desired by the user. Additionally, because of the pulse width modulation output of the microprocessor  52  of the power unit  50  the heat comes in pulsations or heat waves from heating elements allowing heating and an enjoyable experience for a user. Finally, the functions and controls are easily adaptable for custom applications. Thus, at the very least, all of the stated objectives have been met. 
     It will be appreciated by those skilled in the art that other various modifications could be made to the device without the parting from the spirit in scope of this invention. All such modifications and changes fall within the scope of the claims and are intended to be covered thereby.

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