Abstract:
Embodiments of the present invention are directed to a rotary sauce dispensing apparatus for applying a sauce on a receiving surface such as a pizza dough. In one embodiment, an apparatus for producing a flow of a sauce to a dispenser comprises an accumulator including an accumulator chamber with an accumulator inlet to receive and store the sauce and a dispense member configured to dispense the sauce from the accumulator chamber out through an accumulator outlet, and a pump configured to pump the sauce through the accumulator inlet to the accumulator chamber. A diverter valve is coupled with the accumulator and being movable between a closed position to close the accumulator outlet and an open position to open the accumulator outlet. A control member is coupled with the pump, the diverter valve, and the accumulator. The control member is configured to move the diverter valve to the closed position and activate the pump to pump the sauce through the accumulator inlet to the accumulator chamber in a recharge mode, and to move the diverter valve to the open position and drive the dispense member to dispense the sauce from the accumulator chamber out through an accumulator outlet in a dispense mode.

Description:
[0001]    This application is based on and claims the benefit of U.S. Provisional Patent Application No. 60/355,262, filed Feb. 8, 2002, the entire disclosure of which is incorporated herein by reference. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates generally to food dispensing apparatus and, more particularly, to an apparatus for accurately dispensing sauces or condiments or the like.  
           [0003]    Conventional ways of saucing pizza require manual application of a sauce such as a spicy tomato sauce on the pizza dough. Manual application of the pizza sauce is often performed by a novice, hurried chef who distorts the house recipe and produces an uneven coating. Attempts to provide an accurate dose and an even coating require too much time. In addition, using ladles, spatulas, brushes, and the like in handling the pizza sauce may raise sanitary concerns.  
           [0004]    Ladles with brushes or spatulas require a vat of pre-mixed sauce from which is ladled an inconsistent portion. The sauce is brought, dripping to the dough surface, leaving an unsanitary trail of sauce on the table and the sides of the vat. The chef must carefully, expertly spread the sauce across the surface of the dough without leaving puddles or voids or damaged dough. This approach is the least costly, but is also the least consistent and is rather unsanitary.  
           [0005]    Spoodles incorporate a hose or nozzle for pumping the sauce into an attached measuring or spreading ladle. The bottom of the ladle is used to spread the sauce. The spoodle is returned, dripping, to the holding device, thereby leaving an unsanitary trail of sauce on the table and the inside of the holding device. This approach is more costly and more consistent, but is still unsanitary.  
           [0006]    Pouring nozzles are much more consistent in portion control for dispensing the sauce, but they are rather costly. The chef must still carefully and expertly spread the sauce across the surface of the dough without leaving puddles or voids or damaged dough. The spreading device and its storage remain unsanitary.  
         BRIEF SUMMARY OF THE INVENTION  
         [0007]    The present invention is directed to a rotary sauce dispensing apparatus for applying a sauce on a receiving surface such as a pizza dough. A sauce dispensing member is guided to move a dispensing outlet between an edge position above an outer edge of the pizza dough and a center position above a center of the pizza dough to dispense the sauce from the dispensing outlet on the pizza dough. This improves sanitation of the delivery system. The sauce dispensing member is designed to provide the desired consistent thickness of the sauce on the entire pizza surface.  
           [0008]    In accordance with an aspect of the present invention, an apparatus for dispensing a sauce on a receiving surface comprises a rotating table configured to support and rotate the receiving surface thereon around an axis generally perpendicular to the receiving surface for receiving the sauce. A sauce dispensing member has a dispensing outlet disposed above the rotating table to dispense the sauce on the receiving surface disposed on the rotating table. The sauce dispensing member is movable between an edge position above an outer edge of the receiving surface and a center position above a center of the receiving surface. A controller is coupled with the sauce dispensing member and configured to control a speed of movement of the sauce dispensing member between the edge position and the center position to form a layer of sauce on the receiving surface.  
           [0009]    Another aspect of the invention is directed to a method of dispensing a sauce on a receiving surface. The method comprises rotating the receiving surface, providing a sauce dispensing member having a dispensing outlet disposed above the receiving surface, and automatically guiding the sauce dispensing member to move the dispensing outlet between an edge position above an outer edge of the receiving surface and a center position above a center of the receiving surface at a speed to dispense the sauce from the dispensing outlet to form a layer of sauce on the rotating receiving surface.  
           [0010]    In accordance with another aspect of the present invention, an apparatus for producing a flow of a sauce to a dispenser comprises an accumulator including an accumulator chamber with an accumulator inlet to receive and store the sauce and a dispense member configured to dispense the sauce from the accumulator chamber out through an accumulator outlet, and a pump configured to pump the sauce through the accumulator inlet to the accumulator chamber. A diverter valve is coupled with the accumulator and being movable between a closed position to close the accumulator outlet and an open position to open the accumulator outlet. A control member is coupled with the pump, the diverter valve, and the accumulator. The control member is configured to move the diverter valve to the closed position and activate the pump to pump the sauce through the accumulator inlet to the accumulator chamber in a recharge mode, and to move the diverter valve to the open position and drive the dispense member to dispense the sauce from the accumulator chamber out through an accumulator outlet in a dispense mode.  
           [0011]    Another aspect of the invention is directed to a method of producing a flow of a sauce to a dispenser. The method comprises providing an accumulator including an accumulator chamber with an accumulator inlet to receive and store the sauce. The accumulator has a dispense member configured to dispense the sauce from the accumulator chamber out through an accumulator outlet. In a recharge mode, the method comprises closing the accumulator outlet and activating a pump to pump the sauce through the accumulator inlet into the accumulator chamber. In a dispense mode, the method comprises opening the accumulator outlet and driving the dispense member to dispense the sauce from the accumulator chamber out through the accumulator outlet.  
           [0012]    In accordance with another aspect of the present invention, a system for producing a flow of a sauce to a dispenser comprises a rotating table configured to support and rotate the receiving surface thereon around an axis generally perpendicular to the receiving surface for receiving the sauce, and a sauce dispensing member having a dispensing outlet disposed above the rotating table to dispense the sauce on the receiving surface disposed on the rotating table. The sauce dispensing member is movable between an edge position above an outer edge of the receiving surface and a center position above a center of the receiving surface. A sauce pumping device is configured to deliver a flow of the sauce to the sauce dispensing member. A controller is coupled with the sauce pumping device and configured to control a sauce flow rate of the flow of the sauce to the sauce dispensing member based on a rotational speed of the rotating table and a speed of movement of the sauce dispensing member between the edge position and the center position.  
           [0013]    Another aspect of the invention is directed to a method of dispensing a sauce on a receiving surface. The method comprises rotating the receiving surface; providing a sauce dispensing member having a dispensing outlet disposed above the receiving surface; delivering a flow of the sauce to the sauce dispensing member; guiding the sauce dispensing member to move the dispensing outlet between an edge position above an outer edge of the receiving surface and a center position above a center of the receiving surface; and automatically controlling a sauce flow rate of the flow of the sauce to the sauce dispensing member based on a rotational speed of the rotating table and a speed of movement of the sauce dispensing member between the edge position and the center position.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a perspective view of a sauce pumping system and a rotary sauce dispensing apparatus according to an embodiment of the present invention;  
         [0015]    [0015]FIG. 2 is another perspective view of the sauce pumping system of FIG. 1;  
         [0016]    [0016]FIG. 3 is a simplified schematic view of the sauce pumping system and rotary sauce dispensing apparatus of FIG. 1;  
         [0017]    [0017]FIG. 4 is an exploded perspective view of part of the rotary sauce dispensing apparatus of FIG. 1;  
         [0018]    [0018]FIG. 5 is a lower perspective view of the rotary sauce dispensing apparatus of FIG. 1;  
         [0019]    [0019]FIG. 6 is a perspective of a dispensing arm mechanism in the rotary sauce dispensing apparatus of FIG. 1;  
         [0020]    [0020]FIG. 7 is a cross-sectional view of the rotary sauce dispensing apparatus of FIG. 5;  
         [0021]    [0021]FIG. 8 is a cross-sectional view of the rotary sauce dispensing apparatus according to another embodiment of the invention;  
         [0022]    [0022]FIG. 9 is an exploded perspective view of the rotary sauce dispensing apparatus of FIG. 8;  
         [0023]    [0023]FIG. 10A is an upper perspective view of a rotating platform in the rotary sauce dispensing apparatus of FIG. 1;  
         [0024]    [0024]FIG. 10B is a lower perspective view of the turntable of FIG. 10A;  
         [0025]    [0025]FIG. 10C is a lower perspective view of the turntable of FIGS. 8 and 9;  
         [0026]    [0026]FIG. 11 is an exploded perspective view of the rotary sauce dispensing apparatus according to another embodiment of the invention;  
         [0027]    [0027]FIG. 12 is a cross-sectional view of the rotary sauce dispensing apparatus of FIG. 11;  
         [0028]    [0028]FIG. 13 is a bottom plan view of an accumulator assembly in the sauce pumping system of FIG. 1 according to an embodiment of the present invention;  
         [0029]    [0029]FIG. 14 is a cross-sectional view of the accumulator assembly of FIG. 13 along line XVI-XVI showing a diverter valve in a dispense position;  
         [0030]    [0030]FIG. 15 is a cross-sectional view of the accumulator assembly of FIG. 13 along line XV-XV showing the diverter valve in the dispense position;  
         [0031]    [0031]FIG. 16 is a bottom plan view of an accumulator assembly in the sauce pumping system of FIG. 1 according to another embodiment of the invention;  
         [0032]    [0032]FIG. 17 is a cross-sectional view of the accumulator assembly of FIG. 16 along line XVII-XVII;  
         [0033]    [0033]FIG. 18 is a cross-sectional view of the accumulator assembly of FIG. 16 along line XVIII-XVIII showing the diverter valve in a recharge position; and  
         [0034]    FIGS.  19 A-C show a flow diagram of a method of operating the sauce pumping system and rotary sauce dispensing apparatus of FIG. 1 according to an embodiment of the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0035]    FIGS.  1 - 3  show a rotary sauce dispensing apparatus  10  including a base  14 , which supports thereon a rotating table or turntable  18 . A pizza pan  20  is placed on top of the turntable  18 . A drive motor  22  drives the turntable  18  in rotation while the base  14  remains stationary. The drive motor  22  desirably moves at a constant speed. The pizza pan  20  rotates with the turntable  18 . The turntable  18  includes automatic centering grip members  26  for centering the pizza pan  20 . A pan size sensor or location sensor  28  is disposed below the turntable  18  and are arranged in the radial direction for sensing the position of the automatic centering pins  26 . This turntable mechanism rotates the pizza pan  20  while the pizza sauce is dispensed and applied on a pizza dough placed on the pizza pan  20 .  
         [0036]    For dispensing a sauce, the apparatus  10  employs a dispensing arm  30  which extends from a proximal end supported by the base  14  to a distal end disposed above the pizza pan  20 . The distal end of the dispensing arm  30  is coupled to and supports a nozzle  34 . The proximal end of the dispensing arm  30  is supported on a linear track  38 , and is movable on the linear track  38  by a linear motor  40  to position the nozzle  34  above different radial locations of the pizza pan  20  to dispense the sauce over the surface of the pizza dough on the pizza pan  20 . FIG. 1 shows one dispensing arm  30 . In general, the sauce dispensing apparatus  10  may include one or more dispensing arms. The use of multiple dispensing arms enables the dispensing apparatus  10  to dispense different sauces.  
         [0037]    A power supply  42  and a controller or processor  44  such as a programmable logic circuit (PLC) provide the power and control to operate the linear drive motor  40  and turntable motor drive  22 . An operator control panel  46  is provided for operating the dispensing apparatus  10 . As seen in FIG. 3, the sauce dispensing apparatus  10  includes the centering grips  26  for centering the pan  20  on the turntable  18 . Pan size actuators  52  are coupled to the centering grips  26  to activate the pan size sensor  28  to provide measurement of the size of the pan  20 . One or more rotational actuators  56  are coupled to the turntable  18  to activate the rotational sensor  58  to provide measurement of the rotational speed of the turntable  18 .  
         [0038]    The finished sauce to the dispensing apparatus  10  is supplied by a sauce pumping system  60 . As shown in FIGS.  1 - 3 , the sauce is provided in a container such as a hopper or a vat  62 . The vat  62  is desirably removable and replaceable, and includes an outlet  64  that mates with an inlet  66  of a pre-mix inlet adapter  68 . The outlet  64  and inlet  66  may form a vacuum sealed connection. A valve  70  such as a ball valve is provided near the outlet  64  of the vat  62 , and can be opened after the connection is formed between the vat  62  and the adapter  68 . An empty hopper sensor  72  is provided in the adapter  68  to sense and inform the controller  44  if the hopper  62  is empty and needs to be replaced. The pre-mix inlet adapter  68  pre-mixes the sauce for improved consistency. The sauce is driven by a pump  76  through an accumulator assembly  80  having an inlet  81  to the dispensing apparatus  10 . A shut-off valve  82  is desirably provided near the dispenser  34  to shut off the sauce flow when appropriate to minimize dripping.  
         [0039]    The pump  76  is typically a hydraulic pump such as a double diaphragm pump, but may be any suitable type of pump. A compressed gas or air source  84  supplies a gas or air through a safety valve  86  and a filter regulator  88  to a four-way valve  90 , which serves as a control member or control valve for controlling operation of the pumping system  60 . The four-way valve  90  has two positions. In position A, the four-way valve  90  directs air flow through a pressure regulator  92  to the shut-off valve  82  and through an air flow reduction circuit  94  via a T-connector  95  to the accumulator  80 . In position B, the four-way valve  90  is coupled via a T-connector  96  to the pump  76  and to a diverter valve  97  disposed at the outlet of the accumulator assembly  80 . The operation of the sauce pumping system  60  is described in greater detail below.  
         [0040]    [0040]FIG. 4 more clearly illustrates the sauce dispensing arm assembly including the dispensing arm  30  and the nozzle  34  disposed at the distal end of the dispensing arm  30 . The dispensing arm  30  has a goose-neck shape, and has a hollow interior for delivering the sauce from the proximal end to the distal end for dispensing through the nozzle  34 . The centering grips  26  are disposed around the outside edge or perimeter  98  of the pan  20 . The pan size sensor  28  is shown as a pan size sensor rack disposed on the base  14  for sensing the position of the pan size actuator  52  connected to the centering grips  26  (see FIG. 3). The sensor rack  28  extends radially generally between the center and the edge of the turntable  18 . As the turntable  18  rotates, the pan size actuators  52  travel along the pan size actuator path  100  and activate the pan size sensor  28 . The size of the pan  20  is determined from the signal generated by the sensor rack  28 . In one embodiment, each pan size actuator  52  has a magnet and the pan size sensor rack  28  includes reed switches that are activated by the magnet of the pan size actuators  52 . The pan size sensor  28  is coupled to the controller  44  as shown in FIG. 3. The controller  44  provides to the linear drive motor  40  the pan size information received from the sensor  28  to define the starting location of the nozzle  34  of the dispensing arm  30  for saucing the pizza on the pan  20 .  
         [0041]    [0041]FIG. 5 shows mounting of the turntable drive motor  22 , linear motor  40 , controller  44 , and operator control panel  46  to the base  14 . The base  14  includes a side slot  104  that allows the dispensing arm  30  to slide along the linear track  38 . The assembly of the dispensing arm  30  and linear motor  40  is more clearly seen in FIG. 6. The nozzle  34  desirably has a longitudinal discharge outlet  106  for discharging the sauce in a ribbon-like pattern as the pan  20  is rotated by the turntable  18  under the nozzle  34 . By moving the dispensing arm  30  toward the center of the pan  20  as it rotates, the sauce is deposited on the pan  20  to cover the pizza dough in the form of a spiral ribbon pattern. FIG. 7 shows a cross-sectional view of the rotary sauce dispensing apparatus  10  as described. In some embodiments, the discharge outlet  106  is variable in size that may be adjusted mechanically and/or electrically. For example, the discharge outlet  106  may be rotatable to change its size. The discharge outlet  106  may decrease in size as it approaches the position above the center region of the pan  20  to reduce the amount of sauce dispensed. This may be used to achieve a more uniform layer of sauce dispensed since the surface area in the center region is smaller than the surface area in the outer edge region.  
         [0042]    As seen in FIGS. 4 and 7, the rotational sensor  58  is disposed on the base  14  for measuring the rotational speed of the turntable  18 . The turntable  18  typically rotates at a constant speed which can be set by the user. The rotational speed is provided by the rotational sensor  58  to the controller  44 . Based on the rotational speed of the turntable  18  and the pan size of the pan  20 , the controller  44  calculates the speed of the linear motor  40  for moving the dispensing arm  30  to dispense the sauce through the nozzle  34  to achieve a substantially uniform layer of sauce (e.g., thickness variation within about 10%). FIGS. 8 and 9 show another embodiment involving a different way of measuring the rotational speed of the turntable  18  and the pan size as described below.  
         [0043]    The turntable  18  in FIGS. 10A and 10B includes three automatic centering grip pins or members  26  disposed above the turntable  18  for centering the pizza pan  20 . More grip members  26  may be used in other embodiments. The grip members  26  are guided to move along radial slots  116 . The grip members  26  are each pivotally connected to a centering link  118  which is pivotally coupled with and driven by a centering device or hub  120 . When the centering links  118  are aligned with the radial slots  116 , the centering links  118  are in the fully extended position. As the centering hub  120  rotates, the centering links  118  pivot relative to the centering hub  120  to move the grip members  26  simultaneously inward. Disposed below the grip members  26  are corresponding pan size actuators  52 , which are used to activate the pan size sensor  28  (FIGS. 3, 4, and  7 ) disposed below the actuators  52  when the grip members  26  stop moving inward upon encountering the edge of the pizza pan  20 . The turntable  18  carrying the pan size actuators  52  rotates with the drive motor  22 , and the pan size actuators  52  activate the pan size sensor  28  at the radial location where the grip members  26  stop. The pan size sensor  28  sends signals to the controller  44  to indicate the size of the pizza pan  20 . The controller  44  then activates the turntable mechanism to rotate the pizza pan  20  and the sauce dispensing arm assembly to dispense the sauce, and controls their operation based on the size and rotational speed of the pizza pan  20 .  
         [0044]    A variety of pan size sensors and pan size actuators may be used. In one example, the pan size sensors  28  and actuators  52  are magnetic, and the signals generated are photoelectronic. Other types of sensors that may be used are optical, mechanical, electrical, and the like. FIG. 10B shows the rotational actuators  56  supported on a hub  122  for actuating the rotational sensor  58 , which may be magnetic, optical, electrical, or the like.  
         [0045]    As shown in FIGS. 8, 9, and  10 C, a different embodiment employs an angular offset scheme of measuring the rotational speed of the turntable  18  and the size of the pan  20 . A sensor  124  which may be an inductive sensor is disposed at a fixed location on the base  14 . The turntable  18  includes three automatic centering grip pins or members  26  disposed above the turntable  18  and slidable along the radial slots  116  for centering the pizza pan  20 . The centering hub  120  drives the centering links  118  to move the grip members  26 . A hub actuator or turntable actuator  126  is fixed to the turntable  18  at a radial position generally corresponding to the radial position of the sensor  124 , so that the turntable actuator  126  may be detected by the sensor  124  as it passes over the sensor  124  during rotation of the turntable  18 . A reference sensor  128  is attached to the centering hub  120  at a radial location generally corresponding to the radial position of the sensor  124 , so that the reference actuator  128  may also be detected by the sensor  124  as it passes over the sensor  124  during rotation of the turntable  18 . Typically, the reference actuator  128  will be angularly spaced from the turntable actuator  126  by an offset angle α, which is related to the positions of the grip members  26  and the size of the pan  20 . During rotation of the turntable, the turntable actuator  126  and reference actuator  128  will be detected by the sensor  124  at two different points in time. The controller  44  can calculate the offset angle a based on the time difference and the rotational speed of the turntable  18 , and determine the size of the pan  20  based on the correlation between the pan size and the angle α, as provided by a lookup table, an equation, or the like. The sensor  124  also serves as a rotational sensor for measuring the rotational speed of the turntable  18  as activated by the turntable actuator  126  passing over the sensor  124  during rotation of the turntable  18 .  
         [0046]    Another way to measure the pan size is illustrated in FIGS. 11 and 12. The outer perimeter or edge  98  of the pan  20  is detected by an optical sensor  127  which is attached to the dispensing arm  30  adjacent the dispensing nozzle  34 . The sensor  127  is oriented downward along a sensor view line  129 . During operation, the dispensing arm  30  is moved from the outside toward the center of the turntable  18 . As the sensor  127  crosses the outer edge  98  of the pan  20  from the surface of the turntable  18 , it detects an abrupt change in height. The optical sensor  127  sends a signal to the controller  44  which determines the size of the pan  20  by the location of the dispensing arm  30  supporting the sensor  127 . The controller  44  may employ a look-up table to look up the pan size. Any suitable optical sensor may be used for the height change detection.  
         [0047]    As shown in FIG. 12, the pan  20  has an outer diameter POD. The outer diameter of the sauce SOD is typically spaced inward from the POD. The size of the spacing depends on the type of pizza. For instance, a deep dish pizza typically has a minimal edge spacing between the POD and the SOD, while a thick crust pizza may have an edge spacing of about 1 inch. A thin crust pizza may have an edge spacing that is less than about 1 inch. The controller  44  may be programmed to automatically set the starting position of the nozzle  34  at the desired SOD based on the selection of the pizza type made by the operator. The sauce dispensing begins at the SOD and terminates at the sauce inner diameter SID. In the embodiment shown, the opening  106  of the nozzle  34  has a constant width to dispense the sauce in a ribbon pattern having a generally constant width. FIG. 12 shows the sauce on the pan  20  in a ribbon pattern with a constant width, which may be about 1-1.25 inches. More typically, the ribbon has some overlap in the edge region near the edge of the pan  20  as opposed to the center region to achieve uniformity in thickness, because the path speed of the nozzle  34  along the spiral path of the pan  20  is larger in the edge region than in the center region which reduces the sauce thickness in the edge region. In general, the overlap decreases from the edge region to the center region. The use of the overlap improves the thickness uniformity. The amount of sauce overlap decreases as the nozzle  34  approaches the center region of the pan  20 . The SID is small, but is typically not zero. Because the surface area of the pan  20  decreases as the nozzle  34  is moved toward the center of the pan  20 , terminating the sauce dispensing prior to reaching the center of the pan  20  avoids excessive sauce buildup in the center and improves the uniformity of the sauce thickness. For instance, the SID may be about 1 inch.  
         [0048]    As illustrated in FIGS.  13 - 18 , the accumulator assembly  80  includes two accumulator chambers  130 . In other embodiments, one or more chambers may be used. Each accumulator chamber  130  includes a gas inlet  132 , a common outlet  134 , and a piston  136  disposed therebetween. The diverter valve  97  is actuatable to open and close the inlet  81 , thereby allowing or blocking sauce flow into the chambers  130 . The diverter valve  97  as shown is actuatable by air through an air cylinder  140  to move between an open position and a closed position. In the dispense mode, the diverter valve  97  is in the closed position to close the inlet  81  from the pump  76 . In the recharge mode, the diverter valve  97  is in the open position to open the inlet  81  from the pump  76 . During recharge as shown in FIGS.  16 - 18 , the diverter valve  97  moves away from the inlet  81  and the sauce enters the sauce inlet  81  from the pump  76  into the accumulator chambers  130 . The diverter valve  97  provides an optional feature in the recharge mode of closing the outlet  134  to shut off of the sauce flow out of the accumulator assembly  80  to minimize or eliminate dripping due to back pressure buildup in the line between the accumulator assembly  80  and the sauce dispenser  34 . This back pressure may be caused by the presence of air bubbles in the sauce that may expand from the pumping and dispensing action. If the shut-off valve  82  is provided, the diverter valve  97  need not close the outlet  134  during the recharge mode. In the dispense mode as shown in FIGS.  13 - 15 , the diverter valve  97  moves to the closed position and blocks the sauce inlet  81 . Pressurized air enters the air inlets  132  into the chambers  130  and pushes the pistons  136  to drive the sauce from the chamber  130  through the outlets  134 , via the open shut-off valve  82 , to the dispenser  34  provided on the dispensing arm  30 .  
         [0049]    The pumping operation of the sauce pumping system  60  in FIG. 3 will now be described. Prior to dispensing the sauce, the pump  76  pumps the sauce from the vat  62  to the accumulator chambers  130  of the accumulator assembly  80 . The air source  84  supplies air through the safety valve  86  and the filter regulator  88  to the four-way valve  90 . The controller  44  sets the valve  90  to the recharge mode at position B. The air flows through the T-connector  96  to the air cylinder  140  of the diverter valve  97  to close the outlet  134  of the accumulator assembly  80 . The air also flows to the pump  76  to pump the sauce to the accumulator inlet  81  to fill the accumulator chambers  130 .  
         [0050]    After the recharge of the sauce in the accumulator assembly  60  is completed, the controller  44  switches the four-way valve  90  to the dispense mode at position A. The pump  76  is deactivated and the diverter valve  97  returns to the open position to permit sauce flow from the accumulator chambers  130  through the accumulator outlet  134 . Air flows through the pressure regulator  92  to the shut-off valve  82  to switch it from the closed position to the open position to permit sauce flow to the dispenser  34  on the dispensing arm  30 . The air also flows through the air flow reduction circuit  94  which controls the air flow to the gas inlets  132  of the accumulator assembly  80  through the T-connector  95 . The reduction circuit  94  includes a first path through a normally open flow line  160  and a second path through a flow reducer such as an orifice  162 . When the sauce dispenser  34  is disposed above the outer portion of the pan  20  between the center portion and the outer edge, the controller  44  directs the air flow through the normally open flow line  160  to drive the accumulator pistons  136  to deliver the sauce from the accumulator chambers  130  to the dispenser  34  at a normal rate. When the sauce dispenser  34  is disposed above the center region of the pan  20 , the controller  44  directs the air flow through the flow reducer  162  instead to drive the accumulator pistons  136  to deliver the sauce from the accumulator chambers  130  to the dispenser  34  at a reduced rate. Because the turntable  18  rotates at a constant speed, the sauce delivery rate needs to be reduced in the center region of the pan to produce a substantially uniform layer of sauce. The reduction in sauce delivery is achieved by reducing the air flow rate to the accumulator  80 . The reduction may be continuous if a sophisticated controller is used to continuously adjust the air flow rate. Experiments have shown that discrete reduction is generally satisfactory. In particular, two discrete rates as provided by the normally open flow line  160  and the flow reducer  162  are used in the specific embodiment shown. The controller  44  switches the air flow to the flow reducer  162  when the dispensing arm  30  moves the dispenser  34  above the center region of the pan  20 . For instance, for a total dispensing time of about 5-6 seconds at a rotational speed of about 90 rpm to cover a pan size having a diameter of about 12 inches, the air flow is switched to the flow reducer  162  at a transition time during approximately the last 1.5 seconds to deposit the sauce at a slower rate on the center region of the pan  20  having a transition diameter of about 4 inches. Of course, other ways of adjusting the gas or air flow rate to control the sauce flow may be used in different embodiments.  
         [0051]    The sauce pumping system  60  advantageously provides a steady flow of sauce to the sauce dispensing apparatus  10 . The sauce may be thick or thin in varying degrees, and the viscosity and consistency of the source may change from bag to bag. The use of the accumulator assembly  80  to drive the sauce to the dispenser  34  provides a robust way of handling sauces of varying viscosity, consistency, and particulate sizes and amounts.  
         [0052]    Based on the input to the control panel  46  by the operator, the controller  44  controls operation of the rotary sauce dispensing apparatus  10  and the sauce pumping system  60  to dispense the sauce, as illustrated in FIG. 3. The operator places a dough loaded round pizza pan  20  on the surface of the turntable  18  amid the centering grip members  26  protruding through the surface of the turntable  18 . The operator presses one or more buttons on the control panel  46  to select the type of sauce and pizza and to activate the centering hub  120  to move the grip members  26  simultaneously inward to center the pizza pan  20  on the turntable  18  (see FIGS. 10A and 10B). When the grip members  26  stop moving inward upon encountering the edge of the pizza pan  20 , the pan size actuators  52  coupled with the grip members  26  activate the pan size sensor  28  on the base  14  at the radial location where the grip members  26  stop (see FIGS. 3, 4, and  7 ). The turntable  18  carrying the pan size actuators  52  is rotated by the drive motor  22  which moves at a constant speed, and the pan size sensor  28  sends signals to the controller  44  to indicate the size of the pizza pan  20 . The rotational speed of the turntable  18  and pan  20  is measured by the rotational sensor  58  which is activated by the rotational actuator(s)  56 .  
         [0053]    The controller  44  activates the sauce pumping system  60  to pump the sauce and opens the shut-off valve  82  to allow the sauce to flow to the dispenser nozzle  34  of the dispensing arm  30 . The recharging of the sauce in the accumulator chambers  130  and the dispensing of the sauce from the accumulator chambers  130  through the dispenser  34  to the pan  20  are described above. The movement of the dispensing arm  30  is controlled based on the size and rotational speed of the pizza pan  20 , as well as the width of the nozzle opening  106  and the time set for dispensing the sauce along the spiral path to cover the dough on the pan  20 . The dispensing arm  30  is driven by the linear motor  40  to move from the edge to the center of the pizza pan  20  along the linear track  38 . The speed of the linear motor  40  is controlled and synchronized with the rotation of the pizza pan  20  to provide a uniform layer of sauce on the pizza dough. The sauce dispensing arm assembly is designed to provide the desired consistent thickness of the sauce on the entire pizza surface. Different ways of estimating the speed of the linear motor  40  may be used. The following formula is one example of calculating the speed of the linear motor  40  based on the rotational speed of the pizza pan, the pan size, and the width of the dispenser outlet  106 :  
         [0054]    The following describes one embodiment of controlling the linear motor  40  to move the dispensing arm  30 . This is merely illustrative, and other schemes may be used. The given parameters include the time to dispense the sauce (Dispense Time), the sauce outer diameter (OD), the sauce inner diameter (ID), and the characteristics of the linear motor  40 . Those characteristics include the Screw Pitch (inches/revolution) and the Motor Driver (steps /revolution). The linear motor  40  runs at a frequency that is updated every 10 ms, which is the Hz Step Time. Thus, 1/(Hz Step Time)=1/10 ms=100 per second.  
         [0055]    The control steps are summarized as follows:  
         [0056]    1. Calculate the #Hz Steps=Dispense Time/Hz Step Time=Dispense Time*100  
         [0057]    2. Calculate the steps/inch (SI) of the linear motor  40  as SI=Motor Driver/Screw Pitch.  
         [0058]    3. Calculate the Pour Steps=(ID-OD)*SI.  
         [0059]    4. Calculate the frequency of the linear motor if a constant frequency is used to dispense the sauce by moving the linear motor at a constant velocity, where Constant Hz=Pour Steps*10/Dispense Time.  
         [0060]    5. Calculate the start frequency (Start Hz), which is a preset percentage (Start Hz %) of the Constant Hz, where Start Hz=Constant Hz*(Start Hz %/100%).  
         [0061]    6. Calculate the total frequency change (Total Hz Change) during the current 10 ms time period, where Total Hz Change=(Constant Hz−Start Hz)*2.  
         [0062]    7. Calculate the frequency step (Hz Step) during the current 10 ms time period, where Hz Step=(Total Hz Change/Hz Step Time)/#Hz Steps=(Total Hz Change*100)/#Hz Steps  
         [0063]    The dispensing arm  30  is moved at a constant or linear accelerating motion during every 10 ms period of the pour. Every 10 ms, the frequency is updated by Hz Step, and the counter #Hz Steps is decremented. When the counter equals zero, the acceleration or deceleration is complete.  
         [0064]    FIGS.  19 A-C show an example of how the controller  44  controls the operation of the sauce dispensing system comprising the dispensing apparatus  10  and the pumping system  60 . At the start  300 , the type of sauce dispensing is selected by the operator in step  302 . The selection may include the type of sauce, type of pizza, and the like. Upon selection of the type, the controller  44  activates the rotation of the turntable  18  in step  304 .  
         [0065]    For the selected type, the controller  44  in step  306  loads the operating values for an extra-large pizza for the selected type. The operating values may include the pan outer diameter POD, sauce outer diameter SOD, sauce inner diameter SID, dispensing time, transition time or transition diameter, and the like. The dispensing arm  30  is moved to a home position in step  308 . The home position is outside the SOD of the largest pizza for the apparatus. After checking to make sure the dispensing arm  30  is at the home position (step  310 ), the arm  30  is then moved to the extra-large outer diameter (XLarge OD) in step  312 . After the dispensing arm  30  has been moved to the XLarge OD (step  314 ), the controller  44  determines whether the pan size sensor has sensed an XLarge pan (step  316 ). If so, the sauce dispensing can begin by following the process flow path  318 .  
         [0066]    If an XLarge pan is not sensed, the controller  44  loads the operating values for a large pizza for the selected type in step  320 , and moves the dispensing arm  30  to the large outer diameter (Large OD) in step  322 . After the dispensing arm  30  has been moved to the Large OD (step  324 ), the controller  44  determines whether the pan size sensor has sensed a Large pan (step  326 ). If so, the sauce dispensing can begin by following the process flow path  318 .  
         [0067]    If a Large pan is not sensed, the controller  44  loads the operating values for a medium pizza for the selected type in step  330 , and moves the dispensing arm  30  to the medium outer diameter (Medium OD) in step  332 . After the dispensing arm  30  has been moved to the Medium OD (step  334 ), the controller  44  determines whether the pan size sensor has sensed a Medium pan (step  326 ). If so, the sauce dispensing can begin by following the process flow path  318 .  
         [0068]    If a Medium pan is not sensed, the controller  44  loads the operating values for a small pizza for the selected type in step  340 , and moves the dispensing arm  30  to the small outer diameter (Small OD) in step  342 . After the dispensing arm  30  has been moved to the Small OD (step  344 ), the controller  44  determines whether the pan size sensor has sensed a Small pan (step  346 ). If so, the sauce dispensing can begin by following the process flow path  318 . If not, the dispensing arm  30  is moved back to the home position in step  350 . After the arm  30  reaches the home position (step  352 ), the process returns to start (step  354 ).  
         [0069]    At the start of the sauce dispensing process flow path  318 , the sauce dispensing nozzle  34  is turned on and the dispensing arm  30  is stopped at the SOD in step  360 . The turntable  18  is allowed to make one full rotation in step  362  to ensure sufficient sauce is dispensed at the SOD. This is desirable because the dispense path is the longest at the SOD and the speed of the nozzle  34  along the dispensing path around the outer circumferential is the highest, so that the sauce thickness will be thin without overlap. After the nozzle  34  stays at the SOD for one full rotation, the controller  44  activates the linear motor  40  to drive the dispensing arm from the SOD to the SID in step  364 . The speed of the linear motor  40  is controlled to ensure a substantially uniform sauce thickness according to the schemes described herein. After the dispensing arm  30  has reached the SID (step  366 ), the sauce is turned off and the rotation of the turntable is turned off in step  368 . The dispensing arm  30  is returned to the home position (step  370 ). After the dispensing arm  30  reaches the home position (step  372 ), the process is done (step  374 ). The pumping system  60  can recharge the accumulator  80  for the next dispensing operation.  
         [0070]    Based on the size and rotational speed of the pan  20 , the controller  44  calculates the time it takes to maintain the sauce flow from the accumulator assembly  60  to the dispenser  34  to sauce the pizza. After sauce dispensing is completed, the shut-off valve  82  is closed and the diverter valve  97  is closed. The sauce pumping system  60  switches from the dispense mode to the recharge mode. The turntable motor drive  22  and the linear motor  40  are stopped to allow the removal of the pan  20  from the turntable  18 .  
         [0071]    The above-described arrangements of apparatus and methods are merely illustrative of applications of the principles of this invention and many other embodiments and modifications may be made without departing from the spirit and scope of the invention as defined in the claims. For instance, the dispenser arm may include multiple dispenser heads or nozzles mounted thereon to dispense different sauces. The operator can select the type of sauce and the controller activates the corresponding dispenser nozzle to dispense the sauce. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims along with their full scope of equivalents.