Patent Publication Number: US-8529119-B2

Title: Mug with stirring mechanism

Description:
This application is a continuation of U.S. patent application Ser. No. 13/088,895, filed Apr. 18, 2011, entitled “Mug With Stirring Mechanism” which issued as U.S. Pat. No. 8,152,361 on Apr. 10, 2012, which is a continuation of U.S. patent application Ser. No. 11/516,427, filed Sep. 5, 2006, (which issued as U.S. Pat. No. 7,946,752 on May 24, 2011), which application claims the benefit of the earlier filing date of U.S. provisional application Ser. No. 60/714,594, filed Sep. 6, 2005. 
    
    
     Various embodiments of the invention are directed to a drinking apparatus with an integrated stirring mechanism to stir the beverage contained therein. Other embodiments are also described. 
     BACKGROUND 
     There have been various attempts at providing a drinking container with a stirring mechanism, to allow the user to stir the beverage without requiring the use of a separate stirring stick or spoon. In one category of such products, the stirring mechanism has been motorized or power operated. An example can be found in U.S. Pat. No. 5,720,552 issued to Schindlegger, in which a stirrer is rotatably attached to the surface of the base of the drinking glass. The stirrer is actuated by a motor inside the base. In an earlier attempt, as seen in U.S. Pat. No. 4,435,084 issued to Calhoun, et al., the stirring mechanism is adapted to be manually actuated from the lower end of a cup. While the former may be too complicated a solution, the latter presents a difficulty for the user when the cup is resting in an automobile cup holder, as the user cannot easily access the bottom of the cup in that case. 
     In another category of drinking containers with integrated stirring mechanisms, the stirrer is attached at the top of the drinking vessel, rather than at the bottom. For example, U.S. Pat. No. 5,586,676 issued to Lynd shows a drinking container cap that has a stirrer depending downwardly from its interior surface. Such a stirrer, however, is fixed in relation to the lid of the container, requiring that the lid be removed in order for the user to stir the beverage. In a more recent effort, namely in U.S. Patent Application Publication No. 2003/0179647 issued to Simba, the stirring device is spring loaded and mounted to the top edge of a drinking vessel. The stirring device is shaped like a paddle and is submerged in the beverage content. The paddle pivots in response to the mechanism being operated by the thumb of the user&#39;s hand that is holding the vessel. This type of mechanism, however, requires that the top of the vessel remain substantially open so as to allow the pivoting movement of the paddle, making it unsuitable for use while riding in an automobile due to spillage. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment of the invention in this disclosure are not necessarily to the same embodiment, and they mean at least one. 
         FIG. 1  shows a section view of a mug, as assembled, in accordance with an embodiment of the invention. 
         FIG. 2  shows an exploded view of the embodiment of  FIG. 1 . 
         FIG. 3  shows a tilted side view of a preferred embodiment of the mug lid. 
         FIG. 4  shows a top view of the lid. 
         FIG. 5  shows a tilted top view of an example lid cover, in accordance with an embodiment of the invention. 
         FIG. 6  shows a tilted bottom view of the lid cover. 
         FIG. 7  shows a side profile of an example manual actuator handle, in accordance with an embodiment of the invention. 
         FIG. 8  shows a tilted profile of the actuator handle. 
         FIG. 9  shows a side view of an embodiment of the infusion compartment. 
         FIG. 10  depicts a bottom view of the lid, according to another embodiment of the invention. 
         FIG. 11  shows a top view of the lid of  FIG. 10 . 
         FIG. 12  illustrates a sectional view of the lid of  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION 
     An embodiment of the invention is a mug or cup that has an integrated stirring mechanism, with a stirring element comprising an infusion or steeping compartment. Other embodiments are directed, more generally, to a beverage container, with an integrated stirring element. A further embodiment comprises a stirring element that is to be rotatably attached to the lid of a cup by being inserted through the lid. In this section we shall explain several preferred embodiments of this invention with reference to the appended drawings. Whenever the shapes, relative positions and other aspects of the parts described in the embodiments are not clearly defined, the scope of the invention is not limited only to the parts shown, which are meant merely for the purpose of illustration. 
     Mug Body 
     As seen in  FIGS. 1 and 2 , an embodiment of the invention is a mug  104  that comprises a mug body to hold a beverage therein. The mug body is preferably thermally insulated. The mug body may be a single layered construction of any suitable materials, including, for instance, plastic, stainless steel, specially treated paperboard as used for disposable beverage cups, or other combinations. The preferred embodiment is dual layered as shown, having a mug body outer layer  104  and a mug body inner layer  105 . These layers may be affixed permanently to each other during the manufacture of the mug, and are designed to create a gap  103  between them that serves to thermally insulate the beverage (which is actually in contact with the inner surface of the inner layer  105 ). The outer layer  104  has an open top and a cylindrical wall extending downward as shown that, in this case, diametrically reduces down to a closed bottom. This tapered exterior shape is also suitable for larger volume containers. As an alternative, the exterior shape of the mug body may be straight tubular, in part or in its entirety. The peak outside diameter may be 2.25 inches to 5 inches, and the overall height may be 5 inches to 10 inches. The outer surface of the outer layer  104  preferably has a non-slip hand grip portion  102 , preferably located as shown in the upper half of the mug body. 
     The size and shape of the outer layer  104  is designed for the mug to fit a standard, vehicle cup holder or other similarly sized and shaped receptacle. Fixed holders are designed to accommodate just one size, e.g. the size of a 12 oz. soda can, or the size of a large, 32 oz. drink. Variable holders have a mechanical adjustment mechanism that adapts to different diameters of the mug. Overall and particularly from a diameter standpoint, the outer layer  104  is smaller than a standard pitcher or other relatively larger liquid container that is used primarily for beverage preparation and storage, rather than drinking, and that will not fit in standard vehicle cup holders. In one embodiment, the range of expected interior volume for the mug is 10 oz.-32 oz. 
     The mug body inner layer  105  has an outer diameter that is smaller than the inner diameter of the outer layer  104  so as to provide the gap  103  that serves to thermally insulate the mug. The inner layer  105  has a rim  111  along its open top edge. The downward facing surface of the rim  111  is to cooperate with the edge of the open top of the outer layer  104 , so as to close off the gap  103  as best depicted in  FIG. 1 . Other ways of forming and closing off the gap between the inner and outer layers are possible. The sidewall of the inner layer  105  may essentially conform to that of the outer layer as shown, in this case, tapering down to a closed, i.e. liquid tight, bottom. In the preferred embodiment shown, the bottom of the inner layer is formed to have a hollow, meant to fit the bottom blunt point  113  of an arm or shaft  118 . The fit is preferably a loose fit that allows the shaft to rotate about its longitudinal axis relatively freely, despite the bottom blunt point  113  being in contact with the hollow surface. This stabilizes the lateral or side-to-side movement of the shaft  118 , while the shaft is being rotated (as described below). 
     Lid 
     Still referring to  FIGS. 1 and 2 , a lid  108  is to fit the mug body at its top opening, to prevent spillage of the beverage that is inside. The lid can be fixed in several different ways, for example, by being screwed on via a threading mechanism or by being snapped on. In the embodiment depicted in  FIG. 1 , the lid is pressure fitted and removably held in place, against the inner surface of the inner layer  105  near the top opening of the mug, by a gasket seal mechanism. In this embodiment, a silicone seal or O-ring  107  is fitted inside a matching groove or hollow  303  (see  FIG. 3 ) in an outer facing, lower portion  302  of the lid, and that entirely surrounds the lower portion  302 . The groove or hollow is formed along the lid&#39;s lower side wall  307  that depends from a generally flat base  406  as shown, and sized and shaped to receive the seal. This seal  107  provides for a snug fit between the lid  108  and the inner surface of the inner mug layer  105 . The snug fit is designed to prevent leaks of the beverage that is contained inside, while allowing the user to easily pry off the lid for washing the mug. 
     The lid  108  is generally designed to prevent significant leakage of the beverage. However, it has a number of holes that have been formed in its generally flat base  406 , for various reasons. These are best seen in  FIG. 4  which shows a top view of a preferred embodiment of the lid. There is a hole  404  that, in this embodiment, is approximately at the center of the base  406 , and is designed to receive a lid cover/manual actuator assembly to be described below. There is also a sipper hole  410  through which the beverage will flow out of the mug body and may then be sipped by the user. To ease this flow, an air or vent hole  408  may also be provided through the base  406 . 
     Note that in the preferred embodiment, the base  406  has a single horizontal wall as best seen in  FIG. 1 . However, as an alternative, the base  406  may have a more elaborate structure (e.g., a multi-layered wall that provides better thermal insulation). 
     Referring now to  FIG. 3 , the lid also has a raised rim  304  at its periphery, whose height, thickness and shape should be selected to feel comfortable when pressing against the users mouth and lips, so as to provide the user a more pleasant drinking experience (in other words, a comfortable mouthpiece for the user to sip from). The rim  304  helps contain any spillage to the area it surrounds, atop the lid. In addition, it provides distance so that the user&#39;s face does not bump into the lid and handle assembly. The sideways and outward facing surface of the rim is, in this embodiment, coextensive with the corresponding surface of the mug outer layer  104 . The rim  304  entirely surrounds the top surface of the base  406  where the holes  410 ,  408  are formed, to also prevent spillage of any liquid that has leaked out of the holes  410 ,  408  and accumulated on top of the base  406 . Although the rim  304  appears in the figures as a separate, vertical wall connected at a right angle to the horizontal top surface of the base  406 , an alternative is a less abrupt interface between the top surface of the base  406  and the inward facing (sideways) surface of the rim  304 . 
     Sipping Mechanism 
     The mug has a sipping mechanism integrated with the lid  108  as follows. The raised rim  304  has two top facing sections  310  that are notched out or recessed. These provide slots for the handles  508  of a lid cover  504  (see  FIG. 5  for a tilted top view of a preferred embodiment of the lid cover  504 ). The lid cover  504  is to lie flat against the top side of the base  406  of the lid. In this embodiment, the two recessed sections  310  are directly across from one another, through the center of the lid. The recesses are designed to receive and guide the respective handles  508  of the lid cover  504  (see  FIG. 5 ). Note how the handles  508  extend out beyond the perimeter of the lid cover  504 . A notch  510  is formed on the underside of each handle  508  beyond the perimeter of the lid cover  504 . This notch  510  is sized to fit over the recessed section  310  of the raised rim  304  (see  FIG. 3 ). 
     The lid cover  504  has a pair of cutouts through its generally flat base  506 , that are also referred to as sipper and air hole indentations  512 ,  513 , respectively. These are large enough to expose their respective sipper and air holes, to provide for beverage and airflow out of and into the mug. Note how the handles  508  on the lid cover  504 , as well as their corresponding recesses  310  in the raised rim  304  ( FIG. 3 ), should be positioned away from the sipper and air holes (and their respective cutouts), so as to provide an unobstructed drinking experience. Bumps or other limiting features  403 ,  405  are formed, in this embodiment on the top side of the lid  108  (see  FIG. 1 ), so as to provide a detent for locking the lid cover  504 . The lid cover  504  can be moved to lock into an open position (indentations  512 ,  513  exposing the sipper and air holes, allowing the user to sip the beverage) and a closed position (sipper and air holes are covered by the base  506  of the lid cover  504 , thereby sealing the mug body). The lid cover  504  may be rotated between the open and closed positions, by the user pushing and/or pulling on one or both handles  508  in a direction perpendicular to the longitudinal axis of the mug. Other types of open/closed locking mechanisms are possible to maintain the lid cover  504  in its respective open and closed positions. Other ways of providing a sipping mechanism that has an open and closed position in the lid  108  are possible. 
     Turning now to  FIG. 6 , a tilted bottom view of the lid cover  504  is shown. The bottom of the lid cover  504  has an upper section  601  extending downward from the bottom side of the base  506 . A ridge or lip  602  is formed on the sidewall of the upper section  601 . The upper section  601  is designed to snap fit into the hole  404  of the lid  108  (see  FIG. 4 ), while still allowing for the lid cover  504  to rotatably slide relative to and in parallel with the lid  108  (between the open and closed positions). An additional O-ring or seal (e.g., fitted to the outward facing side of the sidewall of upper section  601 ) may or may not be necessary between the lid cover  504  and the lid  108 , to prevent leakage of the beverage. 
     Stirring Mechanism 
     The stirring mechanism provides for movement of the shaft/arm  118  to stir the beverage, as controlled from above the lid  108 . The preferred stirring mechanism is now described. Referring back to  FIGS. 1 and 2 , as well as  FIG. 6 , the lid cover  504  has a tubular section  608  that cuts through the base  506 . The tubular section  608  in this case is concentric with the upper section  601  and is located so as to extend through the hole  404  of the lid  108 . The section  608  is designed to receive therein a manual actuator handle  112 . In this example, the actuator handle  112  comprises a knob that is rotatable about its longitudinal axis which is fixed, and whose side profile is depicted in  FIG. 7 . 
     As seen in  FIG. 7 , a top portion  702  of the knob has two substantially circular sides, and two sides that have finger grips  703  molded therein, as best seen in the tilted view of  FIG. 8 . Although the edges of the top portion  702  are shown as substantially rounded, alternative surface treatments are possible. The flat top profile along with the smooth rounded edges, helps reduce any interference with the user&#39;s nose or face, while the user is drinking from the mug. The height of the handle  112  is preferably just enough so that the user&#39;s fingers can get a comfortable grip on each side, yet remain as low in profile as possible as to not interfere with any part of the user&#39;s face during drinking. The molded finger grips may also have ridges that allow the user to better grip the knob and to rotate it in a back and forth motion or around in a continuous direction, to mix the beverage or accelerate the steeping or infusion process, or both. 
     A lower portion  712  of the knob is journaled by the cylinder  608  (see  FIG. 1 ). As depicted in  FIGS. 7 and 8 , in this embodiment, the lower portion  712  is comprised of two cylindrical sections. The upper section, as depicted in  FIG. 7 , is a shorter and fatter cylindrical section that is sized to fit inside the section  601 , and is fitted with a slotted recess  708  around its circumference. The recess is designed to accept an O-ring or other seal piece, to help in leak prevention. 
     The lower section of portion  712  is longitudinally slotted as shown (in this example, to form four equally sized leaves) and fitted with cut outs that are intended to key fit the top portion of an agitator shaft  118  (see  FIG. 1 ). Snap ridges or lips are formed towards the lower end of the portion  712  as seen in  FIG. 7  and in  FIG. 1 , to fix the knob longitudinally inside the cylinder  608 , while allowing free rotational movement of the knob, independent of the lid cover  504 . The mechanism may be designed to allow the actuator handle  112  to be rotated (while fitted inside the lid cover  504 ), either back and forth, e.g. over a limited travel range, or endlessly in one direction, in response to a twisting motion of the user&#39;s forefinger and thumb while gripping the top portion of the agitator handle  112 . It should be noted that while material clearances should prevent the free flow of leakage around the agitator handle  112 , and more specifically any flow between the section  608  inner surface and the outer surface of the agitator handle  112 , other embodiments of the handle  112  may include a push down gasket sealing modification to ensure further resistance to leakage. 
     In the preferred stirring mechanism, as depicted in  FIG. 1 , the shaft or arm  118  has an upper end that is coupled to the agitator handle  112  within the section  608 , to the lower portion  712  ( FIG. 7 ). The shaft  118  is, in this embodiment, located at about the center of the mug body and is to rotate freely about its longitudinal axis via its keyed connection to the agitator handle  112 . The top portion of the shaft  118  is keyed to fit corresponding hollow or slotted sections in the portion  712  of the handle  112 , preferably locking the shaft, i.e. preventing the shaft from moving vertically or laterally relative to the lid. This allows the shaft, as well as the connected infusion compartment to be described below, to be removed from the mug body together with the lid as one piece. 
     At some point below the coupling mechanism that connects the shaft  118  to the handle  112 , an infusion compartment  114  is connected to the shaft  118 . In other words, the infusion compartment is suspended in the mug body from the lid, by the shaft  118 , at any suitable height above the bottom of the mug body. In the preferred embodiment shown, the infusion compartment  114  is fixed relative to the shaft by a keyed connection to the exterior surface of the shaft  118 . For example, the shaft  118  comprises, in this case, a square shaped rod that is meant to act as a keyed connection for a corresponding hollow that is formed centrally in the infusion compartment  114 . Bumps or other limiting features  117  are formed on the exterior surface of the shaft (see  FIG. 1 ), in positions that, in this embodiment, lock the infusion compartment in place, limiting its movement longitudinally relative to the shaft  118 , but allowing rotational movement of the compartment with the shaft (about the shaft&#39;s longitudinal axis). In the example here, the infusion compartment  114  is meant to be slid onto the shaft  118  from the top end, and pressed over a set of bumps  117  which restrict the compartment  114  from floating in the liquid beverage. Other ways of attaching the compartment  114  to the shaft for movement with the shaft (e.g., a jaw mechanism that laterally grips the shaft) are possible. In all such mechanisms, the infusion compartment is deemed suspended in the mug body by a movement mechanism that is based in the lid and that provides for controlled or predefined movement of the infusion compartment relative to the mug body, to promote infusion and stirring of the beverage. 
     Note that there may be two or more positions for bumps  117  defined vertically along the shaft  118 , to fix the compartment  114  in at least two different positions. A position  115  that is closer to the top of the mug may be referred to as the “light brew position”. The infusion compartment in this position remains closer to the surface of the liquid, so that after the user&#39;s initial sips, the liquid level will fall below the infusion compartment, thereby halting the infusion process. Another, lower position may be referred to as the “dark brew position”. In that case, the infusion compartment is suspended deeper in the liquid and therefore allows the beverage to steep for a longer period of time, beyond the initial sips of the user. A particular embodiment of the infusion compartment  114  will be further described below. 
     The stirring mechanism may also include one or more agitation elements or flaps  109  connected to the shaft  118  that encourage further fluid flow and mixing while the shaft is being rotated. In the example shown, the flaps  109  are located below the infusion compartment  114 , although, as an alternative, they could be located above it. Also, the figures show two flaps at about 180 degrees to each other on either side of the shaft  118  as the preferred embodiment, however, a single flap or more than two flaps are also possible. The vertical and lateral dimensions of the flap  109  should be selected to fit the flap within the mug body, as well as provide the desired amount of turbulence to the liquid during rotation. Each flap in this embodiment also has a number of holes through it that are meant to create additional turbulence when the flap is rotating. 
     As mentioned above, at the lower end of the shaft  118 , below the steeping compartment  114  and flap  109 , there is a blunt tip which is sized to fit a corresponding hollow in the mug bottom. This aspect is designed to stabilize the shaft  118  in the lateral direction while still allowing free rotational movement of the shaft around its longitudinal axis. 
     Infusion Compartment 
     Referring now to  FIG. 9 , a tilted side view of an embodiment of the infusion compartment  114  is shown. In this embodiment, the compartment  114  is a removable and reusable attachment that can be fixed to the shaft  118  to rotate therewith. The compartment is designed to hold bagged or loose herbs (e.g., tealeaves) or other infusible beverage substance. The compartment  114  has sufficient volume to hold the proper amount of infusible material, for infusing the liquid volume within the mug body. The compartment  114  has an outer skeletal structure or frame  904  that in this example is made of a rigid plastic or other suitable material that can be immersed in a hot beverage. At the top and bottom sides of the skeletal structure  904  and, in this example, located centrally, are hollows  909  that are keyed to fit the cross-section of the shaft  118  of the stirring mechanism (in this case a square cross-section). The top side of the structure  904  forms a lid  906  that is hinged at position  908 , with a clasp  910  provided to keep the lid in the closed position. The lid  906  may alternatively be at the bottom or at the sidewall of the structure  904 . The open areas of the structure  904  are covered with a mesh barrier, to allow liquid to pass freely while restricting the infusible beverage substance to inside the structure  904  while the beverage is stirred by the rotating compartment  114 . The ribs of the sidewall of the structure  904  may be designed to add to the turbulence in the mug when the shaft  118  is rotating. 
     The compartment  114  is preferably designed to be easily removed from the shaft  118  by the consumer, by in this case pushing the compartment in the direction of the longitudinal axis of the shaft, along the shaft. In this example, the compartment is moved away from the flaps  109  and towards an open, top end of the shaft (assuming the shaft  118  has been decoupled from the handle  112 ). Once released from the shaft, the compartment may be opened, by opening the clasp and pivoting the lid  906  upwards about the hinge. The lid  906 , however, need not be hinged and may be entirely removable from the rest of the structure  904 . Once open, the user can fill the compartment with the infusible beverage substance, affix the lid  906  back onto the structure  904 , and reattach the compartment  114  to the shaft  118 . The compartment  114  may be omitted in cases where the beverage is not an infusible drink. 
     Although the compartment  114  is shown in  FIG. 9  as being substantially drum-shaped, alternative box-type shapes that allow the user to easily place therein (and remove) bare, loose infusion substances are possible. Also, the mechanism for attaching the compartment  114  to the shaft  118  may be different (e.g., one that uses jaws at the perimeter of the compartment, to grasp the shaft, rather than coupling through its center). There may also be a second compartment, attached to the shaft  118  in a manner similar to the infusion compartment  114  but longitudinally offset from it. This second compartment need not have a mesh barrier, and may be used to hold beverage flavoring ingredients, for example a citrus wedge, a piece of ginger or a piece of sugar cane. 
     Other Embodiments 
     Turning now to  FIGS. 10-12 , another embodiment of the invention is illustrated as a mug that a different lid, stirring mechanism, and sipper. As seen in  FIG. 10  which shows a bottom view of the lid  108 , the lid has the cylindrical wall  307  that extends down from its base and on the sideways outward facing surface of which are formed screw-on splines  1005 . A corresponding thread (not shown) is formed on the inner surface of the inner layer  105  near the top opening of the mug, allowing the lid to be screwed onto the top edge of the mug. 
     The embodiment depicted in  FIG. 11  features a different sipping mechanism. In this case, the top to bottom hole  410  that is formed in the lid  108  (to allow beverage flow for drinking) is closed and opened by a flap  1106  that pivots about an axis that crosses the handle  112  at the top surface of the lid  108  as shown. A bottom surface of the flap  1106  has a protrusion  1107  that mates with the hole  410 , to help prevent leakage in the closed position.  FIG. 11  shows the flap  1106  in its open position, in this case pivoted all the way back against the base  406  of the lid  108 . 
       FIGS. 10-12  also illustrate a different stirring mechanism, referred to here as screw drive mechanism. In this case, the arm or shaft  118  extends down from the bottom of the lid and is rotated about its fixed, longitudinal axis. The movement however is in response to the actuator handle  112  atop the lid being pushed along a path by the user&#39;s finger, rather than being rotated about its axis. In this embodiment, the drive mechanism causes the linear, and this case entirely vertical, movement of the handle  112  to be translated into rotation of the shaft  118  below it. In this example, the handle  112  looks like a button from the top of the mug and is fixed laterally, at about the center of the lid. The handle is spring loaded to “pop up” when it has been unlocked by the user. The user can unlock the handle  112  by twisting or rotating it at a predefined distance and then releasing from its down position.  FIG. 11  shows the handle  112  in its down position.  FIG. 12  shows a sectional view with the handle in its pop up position. 
     There are at least two variations to this embodiment of the invention. In one embodiment, the screw drive mechanism limits rotation of the shaft  118  to just one direction. Rotation may be actuated in this case when pushing the handle down. In the other embodiment that is depicted in  FIG. 12 , the shaft  118  rotates in both directions. When pushing down on the handle, the shaft rotates in one direction, and when the handle pops up, the shaft rotates in the other direction. 
       FIG. 10  and  FIG. 12  show further details regarding an implementation of the screw drive mechanism. A bearing structure  1206  extends down from a bottom surface of the base of the lid  108 . The structure  1206  is cylindrical in this case as best seen in  FIG. 10 . The structure  1206  has a hole  1202  through which a rotating hub  1210  is passed and journaled for rotation about its longitudinal axis. A handle guide  1208  has an open region that is used to guide and lock the handle  112  between its down and locked position, and its popped up position. This guide and lock region is substantially L-shaped as shown in  FIG. 10 . In this case, the handle guide  1208  and the bearing structure  1206  are formed as openings in the same cylindrical piece that extends down from the base of the lid. The former is in the sidewall  1207  and the latter is in a bottom plate  1209 . 
     The handle  112  has a top  1216  from which depends downward a sidewall  1213 , as best seen in  FIG. 12 . One or more button lock tabs are formed on the sidewall  1213 , to engage with the substantially L-shaped guide and lock opening in the handle guide  1208  of the lid. The tabs are shaped and dimensioned to be slidably guided by the vertical section of the guide and lock opening, and hook up with the horizontal section of that opening, after having been moved into position therein by the user rotating the handle  112 . Once in this lock position, the handle is kept there by the force of a compressed spring  1215  that is pushing against the bottom plate  1209  and the top of the handle  112 . A spring guide section  1213  is provided that serves to not only guide the spring  1215  on its outward facing surface, but also serves to journal the hub  1210  on its inward facing surface. The guide  1213  and plate  1209  may be a separate, single piece that is attached to the rest of the lid during manufacture. Other ways of locating the spring, so as to urge the handle  112  into its popped up position, are possible. The tabs may also serve to limit upward movement of the handle to prevent the handle from completely dislodging itself from the lid, under the force of the spring. An outer cup  1217  may be fitted over the bearing structure  1206 , to further support the hub  1210  about its axis and to prevent beverage leakage from the mug body. 
     Further details regarding the screw drive mechanism are as follows. A linearly reciprocating, elongated helical screw shaft is provided, a top portion of which is attached to the top  1216  of the handle  112 . The attachment is such that relative rotational movement between the two parts is precluded. In this embodiment, both the handle  112  and the attached helical shaft move only linearly, in this case, guided along the vertical axis, and not rotationally relative to the lid. This is achieved by keying the handle to the corresponding slot in the L-shaped opening of the handle guide  1208 . 
     In the screw drive embodiments, the arm or shaft  118  is coupled at its top portion with a bottom portion of the rotating hub  1210 , to rotate therewith. In one embodiment, the helical shaft never disengages from the rotating hub  1210 , during operation of the handle  112  to stir the beverage. In that case, the rotational movement of hub  1210  is directly connected to linear movement of the helical shaft. This in turn allows the stirring element that is attached to the arm or shaft  118  to spin in one direction while the helical shaft is on its way down, and in the other direction while the helical shaft is on its way up. 
     In one embodiment, when the handle  112  is pressed down, the helical shaft in the handle passes through and engages a slot in the rotating hub  1210 . Since the helical shaft is precluded from rotating about its longitudinal axis, its linear movement through the slot forces the hub  1210  to rotate about the axis. In other words, the slot rotates about the axis and along the grooves of the helical shaft as it engages the downwardly moving helical shaft, thus rotating the stirring element attached below it. Other ways of translating linear movement of the handle  112 , as actuated manually from above the lid, into rotational movement of the arm or shaft  118  are possible. 
     For example, in yet another embodiment, a 3-piece hub assembly is used, instead of a possible single piece version in the above embodiment, that constrains the hub to spin in a single direction. In such an assembly, the lower portion has a connection to the shaft  118 , cylindrical walls and a top surface that is fitted with hollows to receive teeth formed in the middle section (to be described below). The top of this section also has a round hollow found at its center that is meant to fit the middle section. The middle section has a cylindrical base which is sized to fit the hollow found at the center of the lower section. This piece is fitted with downward facing teeth that fit into the corresponding recess found in the lower piece. The top is fitted with a slot which is meant to fit the helical shaft. The top section is meant to be snap-fitted to the lower section basically encasing the middle section. When the top and bottom are snapped together with the middle section placed inside of them, there is enough head room for the middle section to “disengage its teeth” from the lower section while the handle moves into its up position. This allows the assembly to spin in only one direction. When the handle is pressed again, the “teeth” find their hollows and the assembly is ready to operate. 
     In a further embodiment of the invention, a method for preparing a beverage uses a stirring device similar to the shaft and stirring element described above. An end of the shaft  118  is inserted through a top to bottom hole in a lid of a beverage cup. The lid and hole are shaped and dimensioned to journal the shaft for rotation. An infusion compartment as described above may be attached to the shaft. The lid is fitted to an open top edge of the beverage cup, such that the journaled shaft and the attached infusion compartment are located inside the cup. This process may be performed by a worker of a retail coffee or tea shop, or a customer thereof. The shaft may be as described above including a rounded blunt point at its bottom end, to prevent damaging the bottom of commonly found fast food cups that are made of, for example, paper or Styrofoam. 
     In this embodiment, the upper portion of the shaft that may have been inserted through the hole in the lid, has breakaway sections, so as to accommodate the different heights of cup sizes that are commonly found, e.g. a lower section for accommodating small cups, a medium section for accommodating medium size cups, and a top section for accommodating larger (taller) cups. The end of the shaft, at the tall section, preferably forms a point sharp enough to puncture commonly found fast food lids. This pointed section should be broken off by the user prior to using the beverage cup. The shaft may also be “broken away” at the desired one of the different sections, so as to fit the height of the selected cup. The top end of the shaft thereafter may then be used as a handle, by being twisted back and forth between the fingers of the user&#39;s hand. 
     Note that the entire assembly including the shaft and the attached infuser compartment may be disposable in this case, such that for every beverage that is made by the coffee or retail shop, a separate stirring mechanism is inserted into each new beverage cup. In a further embodiment, a knob or other retaining portion may be fitted to the top of the shaft, so as to provide a larger handle for the user, as well as prevent the shaft and the infusion compartment from sliding out of the hole. This further handle piece can be designed to snap or pop onto the top end of the shaft. 
     The invention is not limited to the specific embodiments described above. For example, the flap  109  of the stirring element is shown as being integrally formed with the shaft  118  (out of the same piece of material). An alternative there is to manufacture the flap  109  as a separate piece, and provide an attachment mechanism (e.g., one having limiting features similar to bumps  117 ) for attaching the flap  109  to the shaft. Also, the base of the lid has a completely flat and horizontal surface as seen in the figures, and the raised rim has a constant height all around the base. An alternative there is to provide the raised rim with varying height, and/or a lid whose base has an uneven or sloping, i.e. not entirely flat, top surface. In yet another alternative, the manually actuated arm movement described above for the stirring action can be electronically powered by a motor based in the lid, or it can be mechanically powered by a wind-up mechanism that stores mechanical energy and then releases it (to cause the stirring element to move) upon the user pushing a button or lever atop the lid. Accordingly, other embodiments are within the scope of the claims.