BACKGROUND  
       [0001]     The travel mug has been a widely popular car accessory for many years. While traveling in a car, many drivers drink coffee, orange juice or iced tea in their vehicles. A wide variety of mugs and mug handle  50  designs have been introduced in public since the beginning days of the cup holder. The cup holder has enabled all drivers to hold their favorite beverage while driving.  
         [0002]     While the convenience of having a beverage on the road cannot be ignored, a driver may divert attention from driving and attend to the drink. A driver may add sugar and cream to coffee. A driver may also add sugar to iced teas. In orange juice, a driver may also prefer a high pulp orange juice. Because there is no easy way to stir the drink, having a beverage that requires mixing can be a hazard and diversion to the driver.  
         [0003]     Other self mixing methods has been incorporated in beverage containers. The self-stirring pitcher as shown in U.S. Pat. No. 4,967,939 provides a mixing of liquid by pumping liquid from the bottom of the container to the top of the container through a hollow handle  50 . This method requires pumping liquid.  
       OBJECT OF THE INVENTION  
       [0004]     To allow a person to hold a beverage container and stir its contents with only one hand. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  is an isometric view of the first embodiment.  
         [0006]      FIG. 2  is a side sectional view of the first embodiment.  
         [0007]      FIG. 3  is a side sectional view of the second embodiment.  
         [0008]      FIG. 4  is an isometric view of the inside housing of the first embodiment.  
         [0009]      FIG. 5  is a perspective view of upper portion of the inside housing, showing the elastic cord. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0000]     Double Housing  
         [0010]     As shown on  FIG. 1  and  2 , the present invention includes a travel mug having an outside housing  20  and an inside housing  70 . The inside housing  70  is preferably made of plastic. The outside housing  20  is preferably made of stainless steel. The outside housing  20  has a cylindrical configuration and is capable of holding an inside housing  70 . The outside housing  20  has an axle connection to the inside housing  70  at the bottom center of the inside surface of the outside housing  20 . The outside housing  20  has a connection to a handle  50 . The handle  50  allows a user to hold the mug by hand. The handle  50  can be ergonomically shaped to a hand. A handle  50  is formed on the outside housing  20  so that a user holding the handle  50  can manipulate and rotate the inside housing  70 .  
         [0011]     The inside housing  70  freely rotates inside the outside housing  20 . The inside housing  70  is connected to the outside by an axis of vertical rotation at the bottom portion of the inside housing  70 . The inside housing  70  holds the beverage and is not porous or permeable by liquid. The inside housing  70  being cylindrical in basic configuration includes an axial connection to the inside of the outside housing  20 .  
         [0012]     The inside housing  70  has a protrusion nub  60  allowing a user to grasp the handle  50  with one hand, and stir contents of the beverage by manipulating and rotating the protrusion nub  60  mounted on the inside housing  70 . The protrusion nub  60  allows a user to rotate the inside housing  70  with any finger or thumb while holding the handle  50  with the remainder of the hand. Alternatively, the protrusion nub  60  can be replaced by a depression on the surface of inside housing  70 , whereby the depression forms a finger groove allowing a user to put his finger inside the depression and rotate the inside housing  70 .  
         [0013]     The protrusion nub  60  is shown as a tab extending from the upper portion of the inside housing  70 . Preferably, the protrusion is placed on the portion of the inside housing  70  that covers the uppermost edge of the outside housing  20  forming a rim  80 . The rim  80  is formed by the inside housing  70  extending over the top edge of the outside housing  20 . Thus, a user&#39;s lips can drink from the beverage container touching only the rim  80  of the inside housing  70 .  
         [0014]     An improvement on the rotating inside housing  70  includes a spring element attached to the inside housing  70 . The spring element exerts rotational force on the rotating inside housing  70 . A user manipulating the inside housing  70  past an equilibrium position of rest creates potential energy stored within the spring. The spring pulls the inside housing  70  toward a neutral position which is also called the equilibrium position of rest and creates a reciprocating rotational motion of the inside housing  70  upon release of a user&#39;s finger. Vernacularly, the user flicks the inside housing  70  and the rotation with counter rotation mixes the beverage. The spring allows a user multiple counter rotations with a single flick.  
         [0015]     The spring can be implemented as a pair of diametrically opposed elastic cords wound around the upper portion of the rotating housing. Here, the first rubber or polymer elastic cord  75  produces force pulling the inside housing  70  in a clockwise direction when the user exerts rotational force in a counterclockwise direction past the equilibrium position of rest. The second the elastic cord produces force pulling the inside housing  70  in a counterclockwise direction when the user exerts rotational force in a clockwise direction past the equilibrium position of rest. The spring can also be a metal leaf spring. Preferably, a single leaf spring is used for simplicity and cost. However, a pair of opposing the leaf springs can be used. A first leaf spring can exert rotational force in a counterclockwise direction past the equilibrium position of rest when a user produces force in a clockwise direction. A second leaf spring can exert rotational force in a clockwise direction past the equilibrium position of rest when a user produces force in a counterclockwise direction.  
         [0016]     The axis of rotation is vertical. The inside housing  70  and outside housing  20  can be joined by a bearing. Preferably, a ball bearing, or mechanical steel bearing is not used because of cost and weight. However, acceptable substitute and the equivalent mechanical motion can be produced by forming a depression in the lower portion of the outside housing  20 . If the outside housing  20  is made of stainless steel, the inside housing  70  should be made of plastic. A protrusion  112  fitting the depression of the lower portion of the outside housing  20  can be formed in the lower portion of the inside housing  70 . The protrusion  112  protrudes from the bottom of the inside housing  70 . The protrusion  112  and the depression  1   15  are coaxial and are positioned at the center of the bottom of the mug. The center of the mug thus receives the axis of rotation.  
         [0017]     The interface between the inside housing  70  and the outside housing  20  is defined at an upper location at the top of the mug. A user generally drinks liquid from the top of the mug. Here, a user may use a drinking straw and suck the beverage from the container. The user may also drink the liquid without a drinking straw by pouring the liquid from the inside housing  70  into the mouth. The inside housing  70  forms a lip over the outside housing  20  which allows a user to drink from the top of the mug without a drinking straw. While an alternative embodiment can have the inside housing  70  and outside housing  20  interface within the mug, this is not preferable because spilled liquid accumulates between the inside housing  70  and outside housing  20 .  
         [0018]     The mixing can be supplemented by an air pump housed within the handle  50  of the container. The handle  50  optionally contains a trigger  172  to bias an air bladder introducing a stream of air into the housing containing the liquid. The air pump embodiment can be implemented with the double housing by introducing the air into an air passage in the inside housing  70 . As shown on  FIG. 3 , the air pumping option can also be implemented independently without a double housing by pumping air into a single housing. Preferably, the air is introduced into the bottom of the container so that air bubbles  140  have maximum travel time and distance.  
         [0019]     A mixing attachment appearing as a fan with blades  180  has an attachment junction on its bottom. The attachment junction snaps onto the bottom of the inside housing for a snug fit. The mixing attachment can be removed by snapping it off of the bottom of the inside housing. By interference fit, the mixing attachment manually and releasable attaches, detaches and reattaches to the bottom of the inside housing. The mixing attachment preferably does not move relative to the inside housing  70 . The mixing attachment preferably rotates relative to the outside housing  20  along the central axis of the beverage container.  
         [0020]     The attachment junction can be formed in a variety of methods. The preferred method is forming the diameter of the mixing attachment so that it snugly fits against the sidewalls of the inside housing  70 . Less preferred structures for the attachment junction include use of a protrusion fitting upon a groove. A protrusion can be formed in the mixing attachment at the attachment junction which fits into a groove formed within the bottom part of the inside housing  70 . Conversely, a protrusion  117  can be formed in the bottom part of the inside housing  70  that attaches to a groove formed upon the mixing attachment.  
         [0021]     The present invention not only can be presented as a mug, but it can also be applied to any cup-shaped container such as pitcher, kettle, etc.  
         [0000]     Air Pump Handle  50   
         [0022]     The handle  50  of the container can be formed as a single piece of plastic. The handle  50  may incorporate a handle holder that is molded around the top portion of the stainless steel outside housing  20 . The handle holder secures the handle  50  to the mug. The container handle  50  protrudes from an upper position having an attachment at an upper end, but it may have an open lower end. In any case, a trigger  172  located within the handle  50  biases an air bladder which forces air through a tube-like air passage  150 . The air passage  150  leads to the bottom of the inside member. The air passage can be mold inside or outside of the plastic bottom of the inside member. The air is released from the bottom of the inside member and travels through the liquid. A user can pump air by the handle  50  and use the air to cool the liquid. A user may thus control the temperature of his coffee by selectively introducing air into the inside member.  
         [0000]     Call Out List of Elements  
         [0000]    
       
           20  Outside Housing  
           50  Handle  
           60  Nub  
           70  Inside Housing  
           75  Elastic Cord  
           80  Rim  
           112  Protrusion  
           115  Depression  
           117  Protrusion  
           140  Air  
           150  Air Passage  
           172  Trigger  
           180  Mixing Attachment
A beverage container comprising an outside housing, an inside housing nesting inside the outside housing, mounted to rotate freely around a vertical axis while inside the outside housing, a protrusion on the inside housing for manual rotation of the inside housing, and a vane attachment comprising at least one vane and attachable to the inside of the inside housing.