Abstract:
An automatic pot stirring device according to the invention includes a state of the art rechargeable battery, adjustable support arms, and a stirring paddle. An important aspect of the invention is that it can be used with various sizes of saucepans already in a cook&#39;s kitchen by adjusting the support arms and the stirring paddle. The device can be used and stored easily, and maintains an attractive design. There is no need for an electrical outlet nearby. Moreover, the device uses efficient engineering and parts to minimize manufacturing costs. The stirring paddle has a fluid dynamic design which assures efficient stirring.

Description:
[0001]    This application claims the benefit of provisional application serial No. 60/371,520, filed Apr. 10, 2002, the complete disclosure of which is hereby incorporated by reference herein. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The invention relates to kitchen appliances. More particularly, the invention relates to cordless electrical kitchen appliances.  
           [0004]    2. Brief Description of the Prior Art  
           [0005]    Though mixing food ingredients in a heated pan has been, throughout history, a basic requirement in numerous cooking recipes, there is currently no product that allows either stirring or mixing to take place in a stove-top heated pan. At the present time, mechanized stirring and mixing must take place in a separate bowl, nullifying the expansive quality that heat brings to many sauces, custards, gravies, gelatins, cereals and more. As a result, the only way to properly stir or mix in a heated pan is by hand. Stirring and mixing by hand can be time consuming, tiring and even dangerous.  
           [0006]    Several attempts have been made during the past three decades to develop a successful automated pan stirrer. However, each design was built upon a significantly flawed premise. For example, T-FAL currently markets an electric saucepan in Europe that contains a built in stirring device. Unfortunately, this device requires that the user purchase an expensive, undersized pan having no other useful purpose. In addition, due to the large currents required by the device for heating the saucepan, its use is limited to locations having an electrical outlet into which it can be plugged. For these and other reasons, the device has failed to gain commercial acceptance in the United States.  
           [0007]    Since the 1960&#39;s, patents have been filed all over the world for stirring devices that can be attached to an existing saucepan. In each instance, the device has been cumbersome and far too expensive to manufacture for commercial acceptance.  
         SUMMARY OF THE INVENTION  
         [0008]    It is therefore an object of the invention to provide an automatic pot stirring device.  
           [0009]    It is also an object of the invention to provide an automatic pot stirring device which can be used with a variety of pots.  
           [0010]    It is another object of the invention to provide an automatic pot stirring device which is electrically operated.  
           [0011]    It is yet another object of the invention to provide an automatic pot stirring device which does not need to be plugged into an electrical outlet.  
           [0012]    It is another object of the invention to provide an automatic pot stirring device which is inexpensive to produce.  
           [0013]    It is still another object of the invention to provide an automatic pot stirring device which is easy to use and to clean.  
           [0014]    In accord with these objects which will be discussed in detail below, the automatic pot stirring device according to the invention includes a battery power supply, adjustable support arms, and a stirring paddle. An important aspect of the invention is that it can be used with various sizes of saucepans already in a cook&#39;s kitchen by adjusting the support arms and the stirring paddle. The device can be used and stored easily, and maintains an attractive design. Moreover, the device uses efficient engineering and parts to minimize manufacturing costs. The stirring paddle has a fluid dynamic design which assures efficient stirring.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is an exploded perspective view illustrating the major component parts of the invention;  
         [0016]    [0016]FIG. 2 is an assembled perspective view illustrating the invention with two adjustable arms deployed and one side of the adjustable paddle extended;  
         [0017]    [0017]FIG. 3 is a side elevational view illustrating the profile of the adjustable paddle;  
         [0018]    [0018]FIG. 4 is a top plan view illustration the invention with all three arms deployed and resting on the lip of a saucepan;  
         [0019]    [0019]FIG. 5 is a broken sectional view of one arm of the invention in a retracted state for use with smaller saucepans;  
         [0020]    [0020]FIG. 6 is a view similar to FIG. 5 illustrating the arm extended for use with larger saucepans;  
         [0021]    [0021]FIG. 7 is an exploded perspective view of an adjustable supporting arm;  
         [0022]    [0022]FIG. 8 is a perspective view of an embodiment of the invention with the paddle removed;  
         [0023]    [0023]FIG. 9 is a perspective view of an embodiment of the invention with the presently preferred paddle;  
         [0024]    [0024]FIG. 10 is a perspective view of the presently preferred paddle;  
         [0025]    [0025]FIG. 11 is a top plan view of the pot stirrer with the presently preferred paddle  
         [0026]    [0026]FIG. 12 is a schematic diagram of a circuit for use in a second embodiment of the invention which permits intermittent stirring;  
         [0027]    [0027]FIG. 13 is a perspective view of a third embodiment of the invention providing times and intermittent stirring with rechargeable batteries; and  
         [0028]    [0028]FIG. 14 is a view similar to FIG. 13 of a third embodiment utilizing a touch sensitive or membrane covered control. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0029]    Turning now to FIGS. 1 and 2, the major components of the stirring device  10  include: a chassis  12 , a cover  14 , a battery holder  16 , an electric motor  18 , a paddle assembly  20 , and three mounting arm assemblies  22   a - 22   c . As seen in the Figures, the chassis  12  is generally divided into three portions, two of which are occupied by footings  24   a ,  24   b  for receiving the battery holder  16  and the third of which  24   c  receives the motor  18  and a drive train  26 . The cover  14  is similarly divided into three parts  14   a - 14   c  which correspond to the three parts  24   a - 24   c  of the chassis  12 .  
         [0030]    The battery holder  16  is provided with the usual spring contacts  28  and connecting wires  30 . The top of the cover  14  (in portions  14   a ,  14   b ) is provided with a removable non-conductive battery cover  32  with interior conductive battery contacts  34 . The wires  30  from the battery holder  16  are electrically coupled to a circuit board  36  which carries a slide switch  38  and which is coupled by brass motor contact extension clips  40  to the motor  18 . The slide switch  38  is covered by the portion  14   c  of the cover  14  and is provided with a decorative thumb slide  42 .  
         [0031]    The motor  18  is preferably a Johnson Electric, part number 02J2035/001 which was designed for electric screwdrivers. As mentioned above, the motor  18  is coupled to the paddle assembly  20  by a gear train  26 . The gear train  26  includes a glass fiber reinforced nylon ring gear  44 , a glass fiber reinforced nylon motor hub gear  46 , six glass fiber reinforced nylon satellite gears  48 , a zinc die cast top gear arm  50 , a zinc die cast bottom gear arm  52 , an oil filled bronze bushing  54 , and a glass fiber reinforced nylon drive gear  56 . The gear assembly is covered by a plastic gear cover  58 , a plastic locking base  60 , and a plastic locking base flange  62 .  
         [0032]    The paddle assembly  20  includes a stainless steel paddle shaft  64  with a stainless steel clip  66  at its lower end, a generally H-shaped plastic paddle  68 , and two generally U-shaped stainless steel TEFLON coated paddle extensions  70 ,  72 . The paddle  68  is removably coupled to the paddle shaft  64  by the clip  66 . The paddle extensions  70 - 72  are adjustably deceived by the ends of the paddle  68  as seen best in FIGS. 2 and 4.  
         [0033]    The cover  14  also defines three longitudinal wells  14   d - 14   f  within which each of the three adjustable arms  22   a - 22   c  are hingedly received. Each arm assembly, e.g.  22   a  shown in FIG. 1, includes a plastic upper outer arm part  74 , a stainless steel lower outer arm part  76 , a plastic upper inner arm part  78 , a stainless steel arm clip  80 , a stainless steel arm guide  82 , a stainless steel spring  84 , an assembly screw  86  and a stainless steel pivot pin  88 . The upper outer arm part  74  is hingedly coupled to the bottom of the well  14   e  by the pin  88  which also holds one end of the spring  84 . The lower outer arm part  76  slides over the part  74  engaging it with flanges. The arm clip  80  and the arm guide  82  are slidably disposed between the parts  74  and  76 . The other end of the spring  84  is coupled to the clip  80  which is fastened to the upper inner part  78  with the screw  86 .  
         [0034]    Referring now to FIGS. 2 and 4, it can be seen that the paddle extensions  70 ,  72  are movable into and out of the paddle  68 . This allows the paddle assembly to be adjusted to pots of different diameter. As seen best in FIGS. 2, 3, and  4  the paddle shaft  64  is rectangular in cross section and slides freely through the center of the apparatus thereby adjusting to pots of different depth.  
         [0035]    FIGS.  2 - 5  show the arms  22   a - 22   c  retracted to their shortest length for suspending the invention over a pot of relatively small diameter. This is illustrated most clearly in FIG. 5 which shows the spring  84  unextended in reference to pot  1 . FIG. 6, however, illustrates the arm extended to accommodate a larger diameter pot  2 . Here the arm clip  80  engaged the lip of the pot  2  with the spring  84  extended. FIGS. 5 and 6 also illustrate a detent  74   a  in the outer arm assembly  74 . This detent is selectively engaged by rotating the locking base  60  which maintains the arms  22   a - 22   c  in a lowered position during operation and allows the arms to be raised for storage.  
         [0036]    The overall dimensions of the apparatus are approximately 3-4″ tall and 3-4″ in overall diameter with the arms folded up. Thus, with the arms deployed but not extended, the apparatus will comfortably fit on a pot approximately 6″ in diameter. With the arms extended, the apparatus will comfortably fit on a pot having a diameter of approximately 9″ in diameter. The paddle shaft is approximately 8″.  
         [0037]    From the foregoing it will be appreciated that operation of the apparatus is very simple. The paddle assembly is installed and the locking base is rotated to allow the three arms to drop and is then rotated to lock them in the down position. The paddle extensions are adjusted to the diameter of the pot. The arms are extended so that the arm clips engaged the lip of the pot. With the apparatus thus in place, the slide switch is moved to start the rotation of the paddle assembly. When done, the switch is moved to stop the paddle assembly from rotation. The apparatus is easily removed from the pot and the paddle assembly is easily removed from the apparatus for cleaning. The locking base is rotated, the arms lifted and locked in place for compact storage.  
         [0038]    Turning now to FIG. 7, the presently preferred supporting arm assembly  22  is illustrated in greater detail. As described above, each arm  22  includes a plastic upper outer arm part  74 , a stainless steel lower outer arm part  76 , a plastic upper inner arm part  78 , a stainless steel arm clip  80 , a stainless steel arm guide  82 , a stainless steel spring  84 , an assembly screw  86  and a stainless steel pivot pin  88 . The upper outer arm part  74  is hingedly coupled to the bottom of the well  14   e  (FIG. 1) by the pin  88  which also holds one end of the spring  84 . The lower outer arm part  76  slides over the part  74  engaging it with flanges. The arm clip  80  and the arm guide  82  are slidably disposed between the parts  74  and  76 . The other end of the spring  84  is coupled to the clip  80  which is fastened to the upper inner part  78  with the screw  86 .  
         [0039]    According to the presently preferred embodiment, the inner part  78  and attached arm clip  80  are designed to extend approximately 1″ from the outer arm parts  74 ,  76 . The arm guide  82  bridges the connection between the inner and outer arm parts. There are two stops  74   c  (the other not seen) on the upper outer arm part  74  which limits the travel of the arm guide  82  by contacting the shoulders  82   a ,  82   b . The clip  80  has a depending stop  80   a  which limits its movement between stops  82   c ,  82   d . A barb  80   b  is provided to engage the rim of a pot. Stops  74   d  (the other not seen) engage the shoulders  76   a ,  76   b  of the lower outer arm part.  
         [0040]    As mentioned above, the hinged coupling of the upper arm part  74  is provided with two locking slots  74   a ,  74   b  which selectively engage the locking base  60  (FIG. 1) which is provided with three raised fins  60   a - 60   c . These fins, when aligned with the locking slots in the hinges of the arms  22  loct the arms in either the raised or lowered positions.  
         [0041]    [0041]FIG. 8 illustrates the invention with the paddle removed from the paddle shaft  64 . Here it can be seen that the lower end of the paddle shaft  64  and the attached clip  66  form a generally U-shaped (inverted) member which engages the paddle (not shown). These members each include detents  64   a ,  66   a  which engaged ridges on the paddle.  
         [0042]    [0042]FIG. 9 illustrates the pot stirrer  10  with a presently preferred embodiment of a paddle  100  and FIG. 10 illustrates the paddle  100  in further detail. Turning to FIG. 10, the paddle  100  includes first and second plow sections  102 ,  108  each having an inner upstanding mover  106 ,  108  and an outer hinged wiper  110 ,  112 . The upstanding movers  106 ,  108  define a central valley  114  having oppositely disposed ridges  116  (the other not seen) which engage the detents  64   a ,  66   a  of the paddle shaft and clip (FIG. 8). According to the presently preferred embodiment the paddle  100  is made of molded plastic (e.g. polypropylene) and the wipers  110 ,  112  are provided with living hinges  118 ,  120 . As shown in FIGS. 9 and 10, the wipers  110 ,  112  have a lower radiused edge. This is designed to wipe the internal corner of a pot as shown in FIG. 11. The plow sections  102 ,  104  are designed to raise the contents of a pot upward and force the paddle downward to the bottom of the pot for a clean wiping action. The movers  106 ,  108  are designed to spin the raised contents of the pot in a circle. It will be appreciated that the paddles are diagonally symmetrical and may be made for either clockwise or counter-clockwise stirring. The paddles shown in the figures are designed for counter-clockwise stirring.  
         [0043]    According to the presently preferred embodiment, the overall length of the paddle shaft is approximately 8.25″. The preferred paddles  100  arte provided in three sizes to fit most popular pot diameters. In each case, the height of the plow sections is approximately 0.75″. The wiper to wiper dimension varies among three paddles, i.e. about 6″, 7″, and 8.25″. The overall height at the center of the paddle also varies among the three sizes, i.e. about 2.3″, 2.2″ and 2.75″.  
         [0044]    As mentioned above, the present invention contemplates three different models: an entry level model which uses four AA batteries and has a simple on-off switch. An intermediate level model includes rechargeable batteries and/or an intermittent operation mode. A high level model includes a timer, a digital display, and an alarm.  
         [0045]    [0045]FIG. 12 is an exemplary circuit diagram offering on-off-intermittent operation. Table 1, below, identifies the electrical parts used in the circuit of FIG. 12.  
                           TABLE 1                       Reference   Part Number   Description   Manufacturer                   C1, C2   0805B104K160BT   0.10 μF/16 V,   BC Components               10%, X7R0805               (Digi-Key               #BC1300CT)       C3   ECJ-2FB1C105K   1.0 μF/16 V, 10%,   Panasonic               X5R, 0805               (Digi-Key               #PCC2249CT       D1   MBRS140   1A/40 Vschottky   International               Rectifier, SMB   Rectifier               (Digi-Key               #MBRS140CT)       Q1   IRLML6401   P-channel   International               HEXFET,   Rectifier               12 V/.050 Ohm,               SOT23 (Digi-Key               #IRLML6401CT)           292-43.2 K   43.2 K, 1/10 W,   Mouser               1% 0805       R2   292-88.7 K   88.7 K, 1/10 W,   Mouser               1% 0805       R3, R5   292-20.0 K   20.0 K, 1/10 W,   Mouser               1% 0805       R4   292-1.00 K   1.00 K, 1/10 W,   Mouser               1% 0805       U1   CD4060BC   CMOS 14-Stage   Various               Ripple Counter,               SOIC16       S1   Na   DPDT SMT   Various               Switch, Center               Off                  
 
         [0046]    [0046]FIG. 13 illustrates another embodiment of a stirrer  210  according to the invention. This embodiment uses a three position switch  212  for selecting continuous or intermittent operation. It is also provided with a timer display  214 , a time programming button  216  and a jack  218  for attaching a battery charger. The timer display  214  is two digit seven segment display, either LCD or LED. The display is coupled to a timer circuit (not shown) which is coupled to the motor (not shown) and the programming button  216 . When the circuit is activated by switch  212 , the display flashes, prompting the user to input a time value by pressing the button  216 . The circuit is arranged so that pressing the button  216  increments the timer to a number of minutes which appears on the display  214 . For example, pressing the button once increments the display by 1 minute. Further pressing increments the time in one minute intervals up to five minutes, after which time is incremented by 5 minutes each press. Thus, the timer can be set for as high as 55 minutes or as little as 1 minute. The timer is preferably coupled to an audio transducer (not shown) so that a sound is heard when the timer expires.  
         [0047]    [0047]FIG. 14 shows yet another embodiment of a stirrer  310  which also includes an on-off switch  312 , a display  314 , a time programming button  316  and a jack  318  for connecting a battery charger. In this embodiment, the switch, display and button are located beneath a touch membrane. In this embodiment as well as the embodiment of FIG. 13, the timer circuit and display are preferably arranged so that the display counts down as the timer is running. Although the presently preferred circuit stops the motor when the timer expires, it could be arranged that expiration of the timer merely sounds the alarm without stopping the motor.  
         [0048]    There has been described and illustrated herein an automatic pot stirring apparatus. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as so claimed.