Abstract:
An ice making device including a control system to regulate the dispensing of manufactured ice to a hopper for subsequent dispensing into a container such as a cup. The control system senses a low level of ice in the hopper and initiates a signal that is sent to a controller. The controller initiates a time delay that prevents discharge of ice from the ice making device to the hopper until a monitored variable about the ice meets a predetermined value. When the value is reached, additional ice is dispensed to the hopper. Such an ice making device has use in combination with a beverage dispensing device.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an ice making apparatus and method particularly adapted for use in conjunction with automatic beverage dispensers or other devices requiring frequent dispensing of small quantities of ice. It is also particularly adapted for ice makers utilizing small hoppers relative to the total amount of ice dispensed which typically make ice continuously during an ice making cycle. 
     Automatic ice makers are well known in the art and are available in many forms and typically have hoppers for temporary storage of manufactured ice. Beverage dispensers of the coin operated type, dispense both ice and beverage when the requisite amount of money is provided and a beverage selection is made. A cup is automatically dispensed, ice is fed to the cup and then beverage is dispensed to the cup. Such vending machines are commonly used in cafeterias and break rooms. A typical vending machine is a model 328 from Crane National Vendors. Many ice makers have control systems to improve their operation and/or efficiency. Typically, the ice maker will cease making ice when the ice bin is full and commence ice making when the ice level in the hopper reaches a low level. Such a control system does not readily adapt itself to ice makers having small hoppers, for example, a four pound capacity hopper, relative to the amount of ice dispensed, like ice makers associated with coin operated beverage dispensers. Nor is such a control system well adapted for ice makers where the amount of dispensed ice varies, sometimes significantly, throughout a day or by day of week. Ice makers using such control systems can produce poor quality ice and present operational problems such as ice clumping. When ice is retained in a hopper for an extended period, it tends to clump together forming large blocks of ice that cannot be dispensed requiring its removal sometimes leaving an empty or nearly empty hopper and thereby potentially unable to meet demand. Also, the ice feeder in the hopper may break the clumped ice and unclumped ice degrading its quality by leaving pieces that are too large or small and may also warm the ice. 
     Clumping can occur at night, over weekends or during other periods when the rate of ice dispensing is reduced. Generally, ice makers associated with vending machines function such that ice in the hopper is not being moved or mixed unless dispensing is occurring or ice is being made which lack of movement can also encourage clumping. Clumping can be due to the temperature in the hopper rising during periods of non-dispensing and non-mixing allowing localized melting of the ice followed by refreezing. Additionally, the weight of the ice itself can cause localized melting also followed by refreezing. Further, continued mixing, as discussed above, can warm the ice, providing conditions which can lead to later clumping and can also degrade the ice quality through breakage. 
     The ice quality problem is exacerbated by current control systems operating in a manner such that when the low ice level is attained, the ice maker is activated and makes ice until the high level sensor turns off the ice maker. No accommodation is provided with such a control method to accommodate fluctuating ice demand during extended operating periods. Lack of ice and poor quality ice presents consumer acceptance problems. 
     Ice makers are many times part of vending machines that are on service routes. Should an ice maker become non-functional, e.g., because of ice clumping, it may be several days between visits by a service person to remedy the situation. A vending machine may then be out of service for extended periods of time causing consumer inconvenience. 
     The apparatus of the present invention includes a control system that is operable to commence ice making upon two or more operating conditions being met with one of the operating conditions being a low ice level in the hopper. The use of two or more operating conditions for control of ice making accommodates fluctuating ice demand and thereby improves operation and ice quality. 
     SUMMARY OF THE INVENTION 
     Among the several objects and features of the present invention may be noted the provision of a device for making ice that utilizes at least two operating parameters to control commencement of ice making; the provision of such a device that is effective for ice makers having small storage hoppers; the provision of such a device that continuously makes ice during an ice making portion of an operating cycle; the provision of such an ice making device that is automatic in operation; and the provision of such an ice making device that provides quality ice. 
     The present invention involves the provision of an ice dispenser having an ice former with an outlet. Ice is discharged from the outlet on command into a hopper positioned for receiving ice discharged from the outlet. A low ice level sensor is operatively associated with the hopper and is operable to monitor a first parameter of the ice dispenser, the first parameter being indicative of a low ice level in the hopper. A controller is operably connected to the ice former and the low ice level sensor and is operable to monitor a second parameter of the ice dispenser, the second parameter being indicative of an operating condition of the ice dispenser. The controller is also operable to reenable the ice former for full discharge of ice by the ice former to the hopper in response to the first and second parameters. 
     The present invention also involves the provision of an ice making device comprising an ice dispenser having an ice former. The ice former has an outlet and is adapted for discharging ice from the outlet on command. The ice dispenser also has a hopper positioned for receiving ice discharged from the outlet and a feeder associated with the hopper operable to feed ice to a discharge for dispensing ice from the hopper. A low ice level sensor is operatively associated with the hopper and operable to monitor a first parameter of the ice dispenser, the first parameter being indicative of a low ice level in the hopper. The low ice level sensor is operable to generate a low ice level signal. A high ice level sensor is operatively associated with the hopper and operable to monitor a second parameter of the ice dispenser. The second parameter is indicative of a high ice level in the hopper and the high ice level sensor is operable to generate a high ice level signal. A controller is operably connected to the ice former, the low ice level sensor and the high ice level sensor and is operable to monitor third parameters of the ice dispenser. The third parameters are indicative of operating conditions of the ice dispenser and include the number of times ice has been dispensed from the hopper and a time period. The controller is operable to reenable the ice former for full discharge of ice by the ice former to the hopper in response to the first parameter and at least one of the third parameters meeting a respective predetermined value. 
     Additionally, the present invention involves the provision of a method of making ice in an ice making device having a hopper and dispensing ice from the hopper. The method includes making ice and discharging the ice at a full discharge rate to the hopper. At least two ice making parameters are monitored, one of which is ice level in the hopper. Full discharge of ice to the hopper is terminated when the ice level reaches a predetermined high ice level. Full discharge of ice to the hopper is reenabled when at least two ice making parameters each meet a respective predetermined value. 
     Other objects and features will be in part apparent and in part pointed out hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an operation flowchart of a controller for an ice making device; and 
     FIG. 2 is side elevation sectional view of an ice making device with control elements shown schematically. 
     Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. 
    
    
     DETAILED DESCRIPTION 
     The reference numeral  10  designates generally an ice making device (FIG. 2) comprising an ice storage hopper  12 , ice former  14  and ice dispenser  16 . A preferred ice making device is model 638090900004 from IMI Cornelius. The ice former  14  includes an auger shaft  18  rotatably mounted in a tube  20 . The auger  18  is driven by a motor  21  operably connected thereto. A freezer section  19  includes refrigeration coils  22  surrounding the tube  20  and operably connected to a refrigeration unit  25  that includes a compressor  23 . Insulation  24  in a housing  26  surrounds the coils  22 . A water inlet tube  27  communicates with the interior  31  of tube  20 . Preferably water flow in the inlet tube  27  is controlled by a water flow control valve arrangement preferably of the float valve type having a water flow control valve  28  and a float chamber  30 . One or more switches  29  are operably connected to the valve  28  signaling high and low water levels in the chamber to control the valve  28 . Preferably the valve  28  is a solenoid operated valve. Water flows into the space  31  between the auger  18  and the interior surface  32  of the tube  20  and freezes and is fed to a discharge  34  at the upper end of the auger  18 . The formed ice  35  breaks into pieces on its own after exiting the tube  20  and is then fed through a bottom opening  36  into the hopper  12 . An ice breaker (not shown)could be provided in the tube  20  to assist in ice breakage if desired. The bottom wall  38  of the hopper  12  is frustoconically shaped, sloping downwardly to its outer perimeter. An ice outlet opening  40  is positioned in a sidewall  42  of the hopper  12  and is operable for dispensing ice to a beverage cup or the like. A door  43  is movably mounted on the sidewall  42  and selectively opens and closes the opening  40  upon command. The command includes a dispensing signal generated by a consumer initiating operation by inserting money and making a selection in the case of an automatic beverage dispenser by actuating a switch  41  or the like. Preferably, the door  43  closes after a predetermined elapsed time of dispensing. The auger  18  has an upper end  44  with a shaft  45  secured thereto. A plurality of paddles  46  are secured to and extend laterally outwardly from the shaft  45 . Rotation of the auger  18  and the shaft  45  with the paddles  46  induces ice flow from the hopper  12  through the outlet  40 . If the auger  18  is not already rotating because of ice making, the signal from the switch  41  will start the motor  21  to achieve ice dispensing and also open the door  43 . After a predetermined time, the door  43  closes and the motor  21  will stop, unless the device  10  is in ice making mode, terminating the dispensing of ice  35  through the opening  40 . 
     Ice level sensing means is provided and is operable to generate signals indicative of a high ice level and a low ice level in the hopper  12 . Any suitable sensing means can be used. Preferably, a diaphragm  47  is movably mounted in the hopper  12 . The diaphragm  47  has an actuator shaft  48  engageable with a switch  49  such as a limit switch. The diaphragm  47  rests on the ice  35  indicating generally the level of the top surface of the pile of ice in the hopper  12 . When the top surface of the ice pile reaches a predetermined high level in the hopper  12 , ID the switch  49  generates a signal such as by making or breaking a circuit indicative of a high ice level. When the ice level lowers from ice dispensing, the diaphragm  47  moves down in the hopper  12  until it reaches a predetermined low level again activating the switch  49  to generate a second signal such as by breaking or making a circuit (the opposite of the switch generating the high ice level signal) indicative of a predetermined low ice level. The diaphragm  47  and switch  49  form both high and low ice level sensors. Other forms of ice level sensors could be used. For example a swing arm arrangement like those used in home refrigerator ice makers could be used. A two switch arrangement could also be used. 
     A controller  50  is operably connected to various components of the ice making device  10  to control the operation thereof. The controller  50  operates in a manner shown in FIG.  1 . Preferably, the controller  50  is a programmable logic circuit device as are known in the art. Ice making is commenced by activating the refrigeration unit  25  and feeding water into the space  31 . The motor  21  is also activated driving the auger  18  to move formed ice  35  to and out the outlet  34  and bottom opening  36 . The formed ice  35  is discharged into and fills the hopper  12  until a high ice level signal is generated by ice reaching the high ice level thereby activating the sensor  49 . When the high ice level signal is generated, the manufacture of ice is at least partially and preferably completely terminated stopping full ice discharge to the hopper  12  (i.e. the production of ice at a generally normal rate). The operation of the ice making device  10  will be discussed in terms of ice making being completely temporarily stopped when the ice  35  in the hopper  12  reaches a predetermined high level as sensed by the high ice level sensor  49 . It is to be understood that the making of ice could be, alternatively, slowed down substantially to stop full ice discharge, for example less than about 20% of normal ice production rates. Ice making ceases when the high level sensor  49  is activated. 
     The high ice level signal, which can be the making or breaking of a circuit, is indicative of a high ice level and is transmitted to the controller  50  and disables the motor  21  and hence the auger  18  and the compressor  23  of the refrigeration unit  25 . Ice  35  is dispensed from the hopper  12  through the opening  40  from time to time. For ice dispensing, the motor  21  is reactivated to drive the auger  18 , shaft  45  and paddles  46  to help move ice to the opening  40 . When the ice  35  reaches a predetermined low level in the hopper  12 , the low level ice sensor  49  generates a signal indicative of the low ice level which could be the making or breaking of a circuit. The controller  50  is further operable to monitor an additional parameter indicative of a second operating condition of the ice making device  10 . The second operating condition can be indicative of current and/or former operating conditions. The controller  50  is operable to reenable the ice forming auger  18  for full discharge of ice  35  by the ice former  14  to the hopper  12  in response to the low level signal and the second operating condition. When the second operating condition reaches a predetermined value and the low ice level signal indicates low ice, the ice former  14 , including the auger  18 , will be reenabled for full discharge of ice to the hopper  12 . The second operating condition can be any suitable operating condition, e.g., elapsed time, the length of time ice has been dispensed, i.e. the total or cumulative amount of elapsed time during which one or more ice has been dispensed since a starting point, number of dispenses of ice from the hopper  12 , etc. Some second operating conditions are monitored from a starting point. Preferably, the starting point is the generation of the low ice level signal, however, it could also be measured from the generation of the full ice level signal. Also, more than one operating condition can be monitored and can be used individually or in combination for reenabling full discharge of ice. 
     It has been found desirable to initiate a time delay (as described below) when the low ice level signal is generated. When ice storage hoppers have small storage capacities, as is typically the case for automated beverage dispensers which can have a full capacity on the order of four lbs., it has been found desirable to generate the low ice level signal when the hopper  12  has ice in the range of about 40% through about 80%, preferably in the range of about 50% through about 70% and most preferably about 60% of the capacity at the full ice level as indicated by the high ice level sensor  49 . The degree of ice fill in the hopper  12  to initiate the low ice level signal will depend on the size of hopper relative to the rate of ice dispensing. Having a significant amount of ice in the hopper  12  provides for the use of a small hopper and dispensing of high quality ice while being able to meet demand for ice. The initiation of a predetermined time delay period with a significant amount of ice in the hopper  12  allows the hopper to be further emptied without jeopardizing the ability to meet demand. typical time delay would be in the range of about ½ hour through about 4 hours, preferably in the range of about 1 hour through about 3 hours and most preferably about 2 hours of elapsed time since the most recent low ice level signal (starting point). 
     Other second operating conditions that can be monitored include the amount of time ice  35  is dispensed and the number of times ice has been dispensed through the opening  40  since the last low ice level signal (starting point). Both are indicative of the quantity of ice that has been dispensed. Preferably, the amount of time of ice dispensing is used as a second operating condition. The ice dispensing time is measured by measuring the length of time the door  43  is open. In a preferred embodiment, the aforementioned time delay period is initiated by the low ice level signal during which time period full ice discharge is disabled until another operating condition is met. As seen in FIG. 1, full ice discharge is reenabled when either the time delay period has elapsed, as described above, or within the time delay period upon meeting another operating condition as described above. When the operating conditions are met, the controller  50  effects commencement of operation of the ice former  14  for full ice discharge to the hopper  12  by activating the compressor  23  and powering the motor  21  to drive the auger  18 . Full discharge of ice is continued until the ice reaches and activates the high ice level sensor  49 . When the high ice level sensor  49  is activated, the full discharge of ice is again ceased. In the described preferred embodiment, the ice making cycle starts again upon receipt of the low ice level signal. It is to be understood that the controller  50  can be programmed for a variety of operating modes, for example, cycle initiation could be the high ice level signal. Rate of ice dispenses could be monitored instead of or in addition to the number of dispenses or total time of dispensing. If the ice making device  10  is used in an environment where there are regular periods of non operation, the controller  50  could be programmed for preselected time periods of stand-by mode such as date, e.g., weekends, holidays, e.g., Thanksgiving, day of week, e.g., weekends, and/or time of day, e.g., early morning hours, when consumers would not normally be present. During such stand-by periods, the ice former  14  would be disabled from full discharge of ice irrespective of the other operating parameters and control functions effected by the controller  50  for normal operation. The controller  50  operates on an ice making cycle basis. A cycle of ice making is between common operating points in successive cycles, e.g., the period between two successive high ice level signals, which is a preferable operating mode, or between two low ice level signals. When an ice making cycle is completed, the controller  50  resets itself for another cycle. The monitoring of the operating conditions will be reinitiated at the appropriate signal and the monitored operating conditions will be remeasured. 
     The operation of the controller  50  is illustrated in FIG.  1 . The operation of the ice making device  10  is described below using a time delay period and the amount of elapsed time of ice dispensing as monitored operating parameters for control of the ice making device. The ice making device  10  is powered up, control box  80 , and the compressor  23  and motor  21  are off, control box  51 . The controller  50  is preprogrammed with initial operating parameter data, control box  82 , with the total cumulative elapsed time of ice dispensing required to disable the time delay period and the time delay period are set. Ice making commences by activating the compressor  23  and the motor  21 , control box  84 . The controller  50  checks the ice level signal, control box  86 , and evaluates the signal for whether or not the hopper  12  is full, control box  88 . If the hopper  12  is not full, ice making continues and if it is full, the compressor  23  and motor  21  are disabled from producing full discharge of ice  35 , control box  90 . After the motor  21  and compressor  23  are disabled, the controller  50  checks the signal from the ice level switch  49  and determines if the hopper  12  is full, control box  94 . If the hopper  12  is fill, the compressor  23  and motor  21  are maintained disabled, control box  96 . If a signal from the switch  41  is received, control box  98 , the controller  50  rechecks the level of ice in the hopper  12 , control boxes  92 ,  94 . If the hopper  12  is not full, control box  94 , the total time of ice dispensing is set to zero and the time delay period is also set to zero, control box  100 . The controller  50  evaluates whether or not the time delay period, after resetting to zero now exceeds the predetermined time delay period, control box  101 . The elapsed time of the time delay period, control box  102 , is summed or monitored, control box  103 . If the predetermined time delay period is exceeded, the compressor  23  and motor are reenabled for full discharge of ice  35 , control box  84 . If the time delay period has not expired or been exceeded, the controller  50  determines the total time of dispensing of ice  35  from multiple dispenses through the opening  40 , control box  104 . The value of the time of ice dispensing is provided by measuring the total time the door  43  is open for multiple ice dispenses, control box  106 , as initiated by a signal generated by activating the switch  41 , control box  108 . The controller  50  determines if the amount of time of ice dispensing exceeds a predetermined value, control box  110 . If the cumulative time of ice dispensing exceeds the predetermined value, the time delay is disabled and the compressor  23  and motor  21  are reenabled for full ice discharge, control box  84 . If the time of ice dispensing does not reach the predetermined value set therefor, the compressor  23  and motor remain disabled, control box  112 . 
     When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
     As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.