Abstract:
A method for preventing holding of one or more of a hot liquid or hot food in a utensil. The method including: configuring a utensil portion for holding one or more of a liquid or food to have a first orientation relative to a handle portion when a temperature of a shape memory alloy neck portion connecting the utensil portion to the handle portion is below a transition temperature and changing the orientation of the utensil portion relative to the handle portion to a second orientation when the temperature of the shape memory alloy neck portion is greater than the transition temperature so as to not hold the liquid or food.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is related to U.S. Pat. No. 8,087,174 issued on Jan. 3, 2012, the entire contents of which is incorporated herein by its reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to utensils, and more particularly, to a spoon having a concave portion for holding a liquid or food when the temperature of the liquid is less than a predetermined threshold (transition) temperature and where the head changes its orientation relative to a handle portion of the spoon making the concave portion unable to hold the liquid or food when the temperature of a shape memory alloy neck portion connecting the concave portion to the handle portion is greater than the predetermined threshold (transition) temperature. 
         [0004]    2. Prior Art 
         [0005]    Many people, especially children and the elderly burn their mouths after eating food that it too hot. For instance, eating soup that is too hot from a soup container often leads to serious burns on the inside of a person&#39;s mouth. In order to prevent such occurrences, a person would have to insert a thermometer into the soup to determine its temperature. Additionally, it is known in the art to use a utensil, such as a spoon, which has a built in temperature sensing device, and a means for indicating that the temperature of the food is too hot, such as a caution symbol. However, children and elderly people often cannot or do not recognize such indications. 
         [0006]    Therefore, there is a need in the art for a simple passive method and device for preventing people, particularly children and the elderly, from eating food that is too hot and can cause burning of the mouth. 
       SUMMARY OF THE INVENTION 
       [0007]    Therefore it is an object of the present invention to provide a utensil, such as a spoon having a passive means for preventing people from eating food that is likely to cause burning of the mouth. 
         [0008]    It is another object of the present invention to provide such utensil in a simple and inexpensive configuration. 
         [0009]    Accordingly, a spoon is provided. The spoon comprising: a handle portion; and a head portion connected to the handle portion, wherein the head portion comprises: a concave portion for holding one or more of a fluid or food; and a shape memory alloy neck portion having one end connected to the concave portion and an other end connected to the handle portion in a first orientation when the shape memory alloy neck portion is at a temperature less than a transition temperature and in a second orientation when the shape memory alloy neck portion is at a temperature greater than the transition temperature, the first orientation being different from the second orientation. 
         [0010]    The second orientation can be offset 90 degrees relative to the first orientation. The shape memory alloy neck portion can be connected to the concave portion at an end of the concave portion. 
         [0011]    The shape memory alloy neck portion can be connected to the concave portion at a point between ends of the concave portion. 
         [0012]    The shape memory alloy neck portion can be a flat strip. 
         [0013]    The shape memory alloy neck portion can be one or more wires, each having the one end connected to the concave portion and the other end connected to the handle portion. 
         [0014]    The concave portion can be formed of a heat conductive material. The heat conductive material is a metal. 
         [0015]    The handle portion can be formed of a heat insulating material. The heat insulating material can be a plastic. 
         [0016]    Also provided is a utensil comprising: a handle portion; and a head portion connected to the handle portion, wherein the head portion comprises: a utensil portion for holding one or more of a fluid or food; and a shape memory alloy neck portion having one end connected to the utensil portion and an other end connected to the handle portion in a first orientation when the shape memory alloy neck portion is at a temperature less than a transition temperature and in a second orientation when the shape memory alloy neck portion is at a temperature greater than the transition temperature, the first orientation being different from the second orientation. 
         [0017]    The utensil portion can be a concave spoon portion. 
         [0018]    The second orientation can be offset 90 degrees relative to the first orientation. 
         [0019]    The shape memory alloy neck portion can be connected to the utensil portion at an end of the utensil portion. 
         [0020]    The shape memory alloy neck portion can be connected to the utensil portion at a point between ends of the concave portion. 
         [0021]    The shape memory alloy neck portion can be a flat strip. 
         [0022]    The shape memory alloy neck portion can be one or more wires, each having the one end connected to the utensil portion and the other end connected to the handle portion. 
         [0023]    The utensil portion can be formed of a heat conductive material. The heat conductive material can be a metal. 
         [0024]    The handle portion can be formed of a heat insulating material. The heat insulating material can be a plastic. 
         [0025]    Still further provided is a method for preventing holding of one or more of a hot liquid or hot food in a utensil. The method comprising: configuring a utensil portion for holding one or more of a liquid or food to have a first orientation relative to a handle portion when a temperature of a shape memory alloy neck portion connecting the utensil portion to the handle portion is below a transition temperature; and changing the orientation of the utensil portion relative to the handle portion to a second orientation when the temperature of the shape memory alloy neck portion is greater than the transition temperature so as to not hold the liquid or food. 
         [0026]    The second orientation can be offset 90 degrees relative to the first orientation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]    These and other features, aspects, and advantages of the apparatus and methods of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where: 
           [0028]      FIG. 1  illustrates a longitudinal cross-sectional view of the first embodiment of a safety spoon. 
           [0029]      FIG. 2  illustrates a longitudinal cross-sectional view of the safety spoon of the embodiment of  FIG. 1  where the temperature of a shape memory alloy neck portion of the spoon head is greater than the predetermined threshold temperature. 
           [0030]      FIGS. 3A and 3B  illustrate two variations of the shape memory alloy neck portion connecting the concave portion of the spoon head to the handle in the present embodiments of the safety spoons. 
           [0031]      FIG. 4  illustrates a longitudinal cross-sectional view of the second embodiment of a safety spoon. 
           [0032]      FIG. 5  illustrates a longitudinal cross-sectional view of the safety spoon of the embodiment of  FIG. 4  where the temperature of the shape memory alloy neck portion of the spoon head is greater than the predetermined threshold temperature. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0033]    Referring now to  FIG. 1 , there is illustrated a first embodiment  200  of a safety utensil in the form of a spoon. Although a spoon is illustrated herein, any utensil can be so configured, such as a fork. In the embodiment of the spoon illustrated in  FIG. 1 , generally referred to by reference numeral  200 , a spoon head  200   a  is attached to a spoon handle  202 . The spoon head comprises a concave portion  201  for holding a hot fluid or hot food product and a shape memory alloy neck portion  203 . Shape memory alloys are well known in the art, such as nickel-titanium alloys (e.g., having a trade name Nitinol). In general, metallic shape-memory alloys undergo a transformation in their crystal structure when cooled from the high-temperature austenite form to the low-temperature martensite form. When a shape-memory material is in its martensitic form, it is easily deformed to a new shape. However, when the material is heated through its transformation temperature, it reverts to austenite and recovers its previous shape with great force. The temperature at which the material reverses its high temperature form when heated can be adjusted by slight changes in material composition and through heat treatment. The shape-memory process can be made to occur over a range of a few degrees, if necessary, and the shape transition can be made to occur millions of times. Heating may be effected, for example, by immersing the head portion in a hot food, such as oatmeal, or in a hot liquid, such as soup. The transition temperature is alternatively referred to herein as the threshold temperature that is chosen such that a temperature at which the shape alloy neck portion  203  deforms can be any temperature greater than a temperature that is uncomfortable to eat and less than a temperature that causes burns in lip and/or mouth tissue. 
         [0034]    When the spoon comes into contact with hot food, the concave portion  201 , which can be made out of a material with high heat conductivity, such as aluminum, plated steel, stainless steel, copper or the like, becomes hot and transmits the heat to the shape memory alloy neck portion  203  connecting it to the handle  201 , thereby causing the shape memory alloy neck portion  203  to heat up above the transition temperature and to deform the same to its preformed configuration  204 , as shown in  FIG. 2 . As a result, the concave portion  201  can be bent down a prescribed angle, for example, around 90 degrees as shown in  FIG. 2 , thereby discarding the food or liquid that was previously contained within the concave portion  201 . 
         [0035]    The handle  202  can be constructed with relatively non-conductive material so that it stays relatively cool and also minimally conducts heat from the shape memory alloy section  204  to allow its temperature to rise rapidly. For example, the handle may be a plastic polymer that is molded over an end  205  of the shape memory alloy neck portion, as shown in  FIGS. 1-3B . 
         [0036]    A top view of a first variation of the embodiment  200  of  FIG. 1  is shown in  FIG. 3A . In this variation, the shape memory alloy neck portion  203   a  is shown to be constructed with a relatively thin strip of shape memory alloy material which is connected to the concave portion  201  on one end such as by welding, brazing or the like and is fixed to the spoon handle  202  on the other end, with the handle being an appropriate food grade plastic that is molded over the end portion  205   a  as shown in  FIG. 3A . 
         [0037]    Alternatively, as shown in the top view of  FIG. 3B  of a second variation of the embodiment  200  of  FIG. 1 , at least one shape memory alloy neck portion  203   b  configured as a wire is used to connect the concave portion  201  to the spoon handle  202 . The handle  202  can be made out of an appropriate food grade plastic that is molded over the end portion  205   b  of the at least one shape memory alloy “wire” neck portion  206 . 
         [0038]    The shape memory alloy wires (of round, square or other shaped cross section) and relatively thin strips are relatively inexpensive and readily available. In the embodiments of  FIGS. 1-3B  only small pieces of thin strips  203   a  ( FIG. 3A ) or wires  203   b  ( FIG. 3B ) of shape memory alloy material are used to connect the concave portion to the spoon handle, both constructed of commonly used materials for these purposes. Thus, the resulting safety spoon products are readily produced and at very low cost. 
         [0039]    It will be appreciated by those skilled in the art that if the safety spoon embodiment  200  of  FIGS. 1-3B  is inserted into a medium such as a hot soup, the shape memory alloy neck portion  203 ,  FIG. 1 , is rapidly heated due to rapid transfer of heat from the concave portion  201  which is in direct contact with the hot soup over most of its surface area and since heat can be transferred to the spoon head via conduction. As a result, heat is also rapidly transferred to the shape memory alloy neck portion  203 , causing it to deform, such as by taking the shape  204  illustrated in  FIG. 2 , thereby preventing the user from ingesting the content contained in the concave portion  201 . However, if the user picks up a piece of solid food such as a hot piece of carrot or potato or the like without inserting the spoon head relatively deep into a food pile, then it may take a certain amount of time for the heat to travel from the concave portion  201  to the shape memory alloy neck portion  203  to cause it to deform to its configuration  204  shown in  FIG. 2 . This issue can be minimized by firstly selecting a highly conductive material for the concave portion  201 ; secondly to make the concave portion  201  thin to minimize its mass thereby the amount of heat that is required to raise its temperature; thirdly by making the shape memory alloy neck portion  203  small and either out of a relatively thin and narrow strip of shape memory alloy or relatively short shape memory wires with small cross-sectional area. 
         [0040]    In an alternative embodiment  220  shown in  FIG. 4 , a distance between a center region  221  of the concave portion  201  and the shape memory alloy neck portion  222  connecting the concave portion  201  to the spoon handle  202  may be reduced to allow for its rapid heating to the aforementioned transition temperature and its consequent deformation, for example to the configuration  223  shown in the schematic of  FIG. 5 . In the alternative embodiment  220 , the frontal section  224  ( FIGS. 4 and 5 ) of the shape memory alloy neck portion  222  is attached close to the mid-section of the bottom side of the concave portion  201 . However, other portions of the shape memory alloy neck portion  222  can still contact the concave portion  201  while not being fixedly connected. As a result, heat is transferred rapidly from the hot food inside the spoon, but more importantly, as the user brings the spoon in contact with food, the regions around the sections  224  and  225  of the shape memory alloy neck portion  222  are heated first. In the present embodiment, the section  225  which is adjacent to the attachment section  224  of the shape memory alloy neck portion  222  is trained to deform as its temperature goes above the predetermined temperature threshold. As a result, the shape memory neck portion  222  is deformed around the indicated section  225  ( FIGS. 4 and 5 ), causing it to bend and assume a second deformed shape, for example, similar to that indicated by the numeral  223 , and thereby bringing the spoon to a configuration such as that shown in  FIG. 5 . 
         [0041]    While there has been shown and described what is considered to be preferred embodiments of the invention, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the exact forms described and illustrated, but should be constructed to cover all modifications that may fall within the scope of the appended claims.