Abstract:
A chilled probe for quickly and conveniently cooling a liquid is positioned to permit a user to insert the probe into the liquid to be cooled. Feedback, in the form of an indication of a representative liquid temperature, is also provided to increase the value of the method and apparatus. Individual sleeves are conveniently provided on a roll to keep the chilled probe from coming into direct contact with the liquid, thereby avoiding contamination between liquid samples being cooled.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to a cooling device. More particularly the present invention relates to a method and apparatus for conveniently reducing a temperature of a liquid such as a hot drink or a laboratory specimen. 
         [0004]    2. Background Art 
         [0005]    Hot drinks are frequently served too warm for comfortable immediate consumption. Consumers of such drinks are accustomed to wait, and blow their breath over the free surface of the hot drink until it has cooled sufficiently to consume comfortably. 
         [0006]    In laboratories, warm fluids are cooled in refrigerators and freezers, both having limited capacity to cool these fluids quickly. 
         [0007]    For the above reasons, there is a need for a method and apparatus for quickly and conveniently cooling warm or hot fluids. 
       BRIEF SUMMARY OF THE INVENTION 
       [0008]    An object of the present invention is to provide a method and apparatus for quickly and conveniently cooling quantities of liquids. Another object of this invention is to provide a method and apparatus for avoiding contaminating liquid samples cooled successively. Still another aspect of the present invention is to provide feedback to a user of the chilled probe, indicating a temperature of the liquid. 
         [0009]    The present invention comprises a chilled probe mounted in a convenient position for inserting into a cup, beaker, or similar container of liquid. The probe is chilled, that is: its temperature reduced, using one (or more) of several refrigeration techniques, and shall have sufficient capacity to cool or chill the liquid at a rate specified for the application. The present invention is not limited to a particular refrigeration technique or cycle. 
         [0010]    Such an apparatus may be set up at a counter in a fast food restaurant or convenience store where customers are wont to purchase coffee, tea, hot chocolate or the like. After the drink has been dispensed and/or served to the customer, said customer may slide a disposable, protective sleeve over the probe to avoid contaminating the drink with other, previously cooled drinks, and to avoid contaminating later cooled drinks. The customer then positions the chilled probe in the hot drink for a brief period of time, until the drink has reached a temperature with which the customer is comfortable. An indication of the liquid temperature is displayed on the unit so the customer knows when to cease cooling the liquid. A representative liquid temperature may be sensed by a sensor immersed in the liquid along with the chilled probe, or by a laser sensor mounted to detect the temperature of the liquid at a point on the liquid&#39;s surface. 
         [0011]    A similar application is at a soup and salad bar, where consumers serve themselves hot soup. The probe, with its protective sleeve, is again used to cool the soup to a comfortable temperature. 
         [0012]    Another application for the instant invention presents itself in medical or chemical labs, or similar. Relatively small samples of blood, urine, or other bodily fluids, as well as chemicals may be at higher temperatures than are ideal for the process through which they must be brought. These fluids may be chilled quickly and conveniently using the present invention. Contamination may be avoided by the use of the aforementioned disposable sleeve. The temperature indicator may be used to determine when the sample has achieved the desired temperature. 
         [0013]    The novel features believed to be characteristic of this invention, both as to its organization and method of operation together with further objectives and advantages thereto, will be better understood from the following description considered in connection with the accompanying drawings in which a presently preferred embodiment of the invention is illustrated by way of example. It is to be expressly understood however, that the drawings and examples are for the purpose of illustration and description only, and not intended in any way as a definition of the limits of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0014]      FIG. 1  is a side elevation view of a cold probe assembly of the present invention; 
           [0015]      FIG. 2  is an elevation view from the front of the cold probe assembly; 
           [0016]      FIG. 3  is a view of the cold probe assembly, mounted on a counter and cooled with a remote refrigeration unit; 
           [0017]      FIG. 4  is a perspective view of a roll of disposable, protective sleeves to be installed over the cold probe; 
           [0018]      FIG. 5  is a side elevation view of a probe having a temperature sensor and a sleeve disposable over the probe; 
           [0019]      FIG. 6  is a flow diagram of a first logic sequence; 
           [0020]      FIG. 7  is a flow diagram of a second logic sequence; 
           [0021]      FIG. 8  is a side elevation view of the probe with flow passages; and 
           [0022]      FIG. 9  is a side elevation view of the probe with Peltier junctions. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    A cold probe assembly  100  is depicted in  FIGS. 1-3 . A temperature of a probe  110  is reduced using a refrigeration cycle, such as a vapor compression refrigeration cycle using a liquid/vapor refrigerant; a gas refrigeration cycle using a gaseous refrigerant; an absorption refrigeration cycle using at least a binary mixture; the Peltier effect; or one of the more recent advances, such as the magnetic refrigeration cycle using a solid refrigerant. A chilled liquid, such as liquid nitrogen may also be used in lieu of a refrigeration cycle to chill the probe  110 . The choice of chilling process may hinge on the cooling needs of the application for which the cold probe assembly is used. The present invention is not limited to a particular chilling process. Refrigeration cycles are covered in many undergraduate thermodynamics textbooks such as  Fundamentals of Engineering Thermodynamics  6 th  ed. by Moran and Shapiro, John Wiley &amp; Sons, Inc., publishers, ISBN-13: 978-0471-78735-8 which is hereby incorporated in its entirety by reference. 
         [0024]    The probe  110  is inserted into a liquid for the purpose of reducing the liquid&#39;s temperature. The probe  110  is preferably fitted with fins  120  to increase a surface area for heat exchange. Additionally, the fins may be arranged to enhance turbulence when a user moves a cup  130  while the probe  110  is in the liquid inside the cup. Turbulence in the fluid enhances heat transfer from the liquid to the probe  110 . 
         [0025]    A temperature sensor  140  is disposed to provide an indication of the fluid temperature  210  to the user of the cold probe assembly  100 . The temperature sensor  140  may be a remote sensor, such as a laser sensor, mounted to read the temperature of a liquid surface  150 . Alternatively, the sensor may comprise a contact sensor  510  (see  FIG. 5 ), such as a thermocouple or thermister mounted on the probe  110  and thermally isolated therefrom. Other types of temperature sensors and other locations for the temperature sensor are possible, and the present invention is in no way limited to a particular temperature sensor type or location. 
         [0026]    The indication of the fluid temperature  210  may be a digital readout, as shown, or a color change—such as from red to blue—or a light or series of lights to convey to a user when to cease cooling the liquid. An audible signal emanating from a tone generator  220  may also be used. 
         [0027]    A temperature control adjustment  160  may be available for adjusting the temperature set point of the probe  110 . In this way, too rapid and too slow cooling, and also icing can be avoided. A thermostat, using the set point from the temperature control adjustment  160  and a signal from the temperature sensor  140 , may be provided to automatically cease chilling the probe  110 . 
         [0028]    A remote refrigeration unit  310  is shown under a counter  320  in  FIG. 3 . It may not be necessary for the refrigeration unit  310  to be remote from the cold probe assembly  100  for at least some applications. However, when rapid cooling, extreme low temperatures are needed, and/or a large cooling load (i.e. many cups in a short time) is likely, the remote refrigeration unit  310  may be provided. Lines  320  carry refrigerant or other chilled fluid to the probe  110  at adequately low temperature and flow rate for the application for which the cold probe assembly  100  is used. 
         [0029]    Disposable sleeves  410  are shown in a roll  330  in  FIGS. 3 and 4 . The sleeve  410  is removed from the roll  330  by tearing at perforations provided between the individual sleeves  410 . The sleeve  410  is then slid over the probe  110 , as illustrated in  FIG. 5 , by the user to keep the probe  110  from contaminating the fluid being cooled, and to keep the fluid from contaminating the probe  110 . After use, the sleeve  410  is thrown away. 
         [0030]    The cold probe assembly may be energized continuously for some applications. That is, the probe  110  may be kept at a low, operating temperature at all times. Alternatively, a button  170  may be provided so a user may initiate the process of bringing the temperature of the probe  110  down. 
         [0031]    Still another alternative is for the cold probe assembly to recognize when a hot or warm liquid is introduced, as shown in  FIG. 6 . A temperature reading  610  is made periodically using the laser sensor  140  or the direct contact sensor  510 , or another sensor technology is employed. The resulting temperature is compared to a threshold value, preferably greater than the ambient, as shown in the comparator block  620 . If the sensor  140 ,  510  does not sense a warm fluid, no further action is taken and another temperature reading  610  is taken at an appropriate time. 
         [0032]    If a warm or hot fluid is sensed, the cold probe assembly is activated  630 , thereby cooling the probe  110 . 
         [0033]    Another energizing strategy, shown in  FIG. 7 , is to sense the presence of the cup  130 , indicated in the sensing block  710 , using an infrared sensor or the like. A decision is made in block  720  whether the cup is present, and if it is not, no further action is taken and another sensor reading is taken in the sensing block  710  at an appropriate time. If the cup is sensed, the cold probe assembly is activated  630 , thereby cooling the probe  110 . 
         [0034]    Two approaches to removing heat from the probe  110  are shown in  FIGS. 8 and 9 . In  FIG. 8 , passages  810  are formed in the probe to permit a chilled fluid to pass through the probe  110  and pick up heat from the probe while heat from the liquid is transferring to the probe. 
         [0035]    In  FIG. 9 , a plurality of Peltier junctions  910  are shown. The Peltier junctions  910  are energized while the probe  110  is in the fluid, and heat is transferred to the probe  110  from the fluid. The heat transferred to the probe  110  is transferred from the probe  110  via the excitation power to the Peltier junctions  910 . 
         [0036]    The above embodiments are the preferred embodiments, but this invention is not limited thereto, nor to the figures and examples given above. It is, therefore, apparent that many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.