Container with lid
BACKGROUND OF THE INVENTION 
     This invention relates to a lid locking and unlocking mechanism for containers, principally household containers for liquids, as, for example, an electric water heating appliance for making tea or instant coffee. In the case of a household device for heating liquids, or for holding hot liquids, it is generally advisable to provide a lid which can be secured in place to minimize the risk of inadvertent spills. Most conventional containers utilize a screw top, a snap top, or a friction fit top. It is also advisable to construct the container so that when the lid is unsecured on the container that fact is obvious at even a casual glance. Most conventional containers do not provide any such visual indicia of unsecured status. In the case of screw-top containers, for example, the secured and unsecured positions of the lid may differ only in rotational position on the container. Snap top and friction fit tops tend to be even more ambiguous as to status. What has been needed, but not provided by the prior art, is a container having a lid which can be selectively rotated to a secured position and to a visually distinct unsecured position. 
     SUMMARY OF THE INVENTION 
     In the container of this invention, the lid can be rotated to a first position in which it is tightly secured to the container body, to a second position in which it is loosely secured to the container body, and to a third unsecured position in which the lid is raised to a visually distinct position above the container body. The container is provided with an upper wall defining a generally circular opening for introducing liquids into the container. Around the perimeter of the opening are two notches. The lid has a shoulder adapted to engage the upper wall when the lid is in a secured position on the container body, and a skirt adapted to be received by the opening. Around the perimeter of the skirt are two upper tabs. Adjacent to each upper tab is a lower tab, at a greater distance from the shoulder than the upper tabs. The upper and lower tabs are adapted to be received by the notches. In the secured position, the lid substantially covers the opening and engages the upper wall. The upper tabs engage or closely underlie the upper wall, to prevent substantial movement of the lid away from the container body. The lid can be rotated to a second position, in which the upper tabs are aligned with the notches. In the second position, the lower tabs underlie, and are spaced from, the upper wall. In the second position, the lid is loosely secured in place, its movement away from the container body limited by the interaction of the lower tabs and the upper wall. The lid can be raised and rotated to a third position, in which the upper tabs engage the upper wall. The upper tabs can be adapted to support the lid so that the shoulder is raised above and generally parallel to the upper wall. Alternatively, the upper tabs can be adapted to support the lid in an offset position in which a portion of the lid engages the container body. In the offset position, the shoulder is in a non-parallel relationship to the upper wall and is substantially out of contact with the upper wall. In either case, the third position is sufficiently distinct from the first and second positions that it is evident even upon casual observation that the lid is unsecured. 
     The lid can also be supported in an elevated position in a fourth rotational position, in which the lower tabs engage the upper wall. In the fourth position, the lid is supported by the lower tabs and by a portion of the lid in contact with the container body. 
     To facilitate operation of the lid and container assembly, an arm and slot can be provided. The arm projects from the skirt and is received by a slot in the upper wall. The arm functions to further secure the lid in the second rotational position and to support the lid in a fifth position. The arm underlies the upper wall when the lid is in the first and second rotational positions. In the third rotational position, the arm is aligned with the slot. In the fourth rotational position, the arm underlies the upper wall. In the fifth rotational position, the upper tabs and the arm engage the upper wall to raise the lid and to support the shoulder out of contact with the upper wall. In the preferred embodiment, the arm comprises a first projection substantially similar to the lower tabs, at approximately the same distance from the shoulder. The arm also comprises a second projection between the first projection and the bottom of the skirt. 
     In the preferred embodiment, the notches and the slot are equally sized cut-outs in the perimeter of the upper wall, spaced equally about the perimeter. All three cut-outs will accept the lower tabs, the upper tabs, and the arm. In this manner, the lid can be secured in place in any one of three orientations. 
     From the above summary, and the following description of preferred embodiments, it is seen that this invention provides a lid and container combination in which in all unsecured positions the lid orientation provides clear notice of its unsecured status. 
    
    
     DRAWINGS 
     FIG. 1 shows, in side perspective, an example of a container of the type to which this invention is adapted. 
     FIG. 2 shows a bottom plan view of the underside of the lid of the container in FIG. 1, and also a top plan view of the container body shown in FIG. 1, with the lid removed. 
     FIG. 3 shows a side elevational view of the lid of the container of FIG. 1. 
     FIG. 4 shows an elevational view of the lid of FIG. 3, taken on line 4--4. 
     FIG. 5 shows a partial elevational view, in partial cutaway, of the container of FIG. 1 with the lid in a first unsecured position. 
     FIG. 6 shows a section view of the container of FIG. 5, taken on line 6--6. 
     FIG. 7 shows a partial elevational view, in partial cutaway, of the container of FIG. 1 with the lid in a second unsecured position. 
     FIG. 8 shows a partial elevational view, in partial cutaway, of the container of FIG. 1 with the lid in a loosely secured position. 
     FIG. 9 shows a section view of the container of FIG. 8, taken on line 9--9. 
     FIG. 10 shows a partial elevational view, in partial cutaway, of the container of FIG. 1 with the lid in a tightly secured position. 
     FIG. 11 shows a section view of the container of FIG. 10, taken on line 11--11. 
     FIG. 12 shows a partial elevational view, in partial cutaway, of the container of FIG. 1 with the lid in a third unsecured position. 
     FIG. 13 shows a partial elevational view, in partial cutaway, of the container of FIG. 1 with the lid in a fourth unsecured position. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     The container of this invention is exemplified by the container 1 shown in FIG. 1. Container 1 comprises body 2 and lid 3. Body 2 and lid 3 may be made of any conventional materials. It is preferred that body 2 and lid 3 be made substantially completely of thermoplastic. Body 2 comprises base 4, upstanding sides 5, pour spout 6, and handle 7. Referring to FIGS. 2-13, body 2 is provided with upper wall 8 defining generally circular opening 9 for introducing liquids into the container. Upper wall 8 has generally planar annular upper face 10, a generally parallel lower face 11, and a lateral face 12 generally perpendicular to upper face 10, defining a first notch 13 and a second notch 14 in upper wall 8. It is preferred that notches 13,14 comprise indentations in lateral face 12 forming lateral cut-outs in upper wall 8. Notches 13,14 can also comprise indentations or slots in upper face 10. Lid 3 comprises flange 20 having generally planar shoulder 21 adapted to engage upper face 10 when lid 3 is secured to body 2, to substantially cover opening 9. It is preferred that shoulder 21 and upper face 10 mate to form a generally liquid tight seal. 
     Lid 3 also comprises generally cylindrical skirt 22 extending generally perpendicularly to shoulder 21, adapted to be received by opening 9. It is preferred that skirt 22 have a diameter of about 90% to about 98% the diameter of opening 9 so that skirt 22 is received closely by opening 9 without binding. Skirt 22 has a height sufficient to extend into opening 9 in substantially all positions of lid 3 on body 2 over opening 9. Skirt 22 serves to help locate lid 3 on body 2, and to reduce heat transfer between the contents of container 1 and the atmosphere. Lid 3 also carries first upper tab 23 and second upper tab 24 which are adapted to be received by first and second notches 13,14. It is preferred that upper tabs 23,24 comprise elongated projections carried by skirt 22 generally perpendicular thereto, and generally parallel to shoulder 21, and that their dimensions be such that they substantially fully occupy notches 13,14 when received thereby. In that manner, upper tabs 23,24 may be easily introduced into notches 13,14 and, when resident in notches 13,14, the interference of upper tabs 23,24 with notches 13,14 prevents substantial rotation of lid 3. Upper tabs 23,24 have top bearing surfaces 25,26, respectively, spaced from shoulder 21 a distance slightly greater than the thickness of upper wall 8 measured as the distance between upper face 10 and lower face 11. 
     Lid 3 also carries first lower tab 28 and second lower tab 29 which are adapted to be received by first and second notches 13,14. It is preferred that lower tabs 28,29 comprise elongated projections similar to upper tabs 23,24, carried by skirt 22 and generally perpendicular thereto, adjacent to upper tabs 23,24, and generally parallel to shoulder 21. It is also preferred that the dimensions of lower tabs 28,29 be such that they substantially fully occupy notches 13,14 when received thereby. In that manner, lower tabs 28,29 may be easily introduced into notches 13,14 and, when resident in notches 13,14, the interference of lower tabs 28,29 with notches 13,14 prevents substantial rotation of lid 3. 
     Opening 9 has an opening axis 15 generally perpendicular to upper face 10. Lid 3 has a lid axis 16 common to opening axis 15 when shoulder 21 is fully engaged with upper face 10, and is adapted to rotated about common opening axis 15 and lid axis 16 between a first rotational position and a second rotational position. In the first rotational position of lid 3 on body 2, illustrated in FIGS. 10 and 11, shoulder 21 engages upper face 10, substantially closing opening 9. In that position, upper tabs 23,24 underlie upper wall 8. It is preferred that top bearing surfaces 25,26 slidingly engage lower face 11. Top bearing surfaces 25,26 can alternatively be closely spaced from lower face 11, without engagement. In a third alternative, upper tabs 23,24 can be slightly non-parallel with shoulder 21, so that a greater distance exists between shoulder 21 and proximate ends 46 of upper tabs 23,24 than between shoulder 21 and distal ends 32 of upper tabs 23,24. If the distance between shoulder 21 and distal ends 32 is the same or less than the thickness of upper wall 8, an interference fit can be accomplished when lid 3 is fully rotated into its first rotational position. 
     In the first rotational position, the interference of upper tabs 23,24 and upper wall 8 limits the movement of lid 3 away from body 2 along axis 15. It is also preferred that a first stop tab 30 be provided to limit the rotational movement of lid 3 on body 2. It is further preferred that first stop tab 30 comprises a projection on skirt 22 generally perpendicular thereto, proximate one of the distal ends 32 of one of upper tabs 23,24. It is most preferred that two first stop tabs 30 be provided, each extending between shoulder 21 and top bearing surfaces 25,26 adjacent distal ends 32 of each of upper tabs 23,24. When lid 3 is completely turned into its first rotational position, upper tabs 23,24 substantially completely underlie upper wall 8 and first stop tabs 30 engage front surfaces 33 of first and second notches 13,14. 
     Lid 3 can be rotated about opening axis 15 and lid axis 16 to a second rotational position in which upper tabs 23,24 are aligned with first and second notches 13,14, illustrated in FIGS. 8 and 9, and shoulder 21 engages upper face 10. In the second rotational position, lower tabs 28,29 underlie upper wall 8, to prevent removal of lid 3 along axis 15. Lower tabs 28,29 are spaced at a greater distance from shoulder 21 than upper tabs 23,24, to allow some movement of lid 3 along axis 15. It is preferred that lower tabs 28,29 be located at a distance from shoulder 21 no greater than necessary to allow lid 3 to be moved axially in its second rotational position sufficiently to elevate bottom bearing surface 26 above upper face 10, to allow lid 3 to be rotated into its third rotational position. It is also preferred that lower tabs 28,29 be adjacent to upper tabs 23,24, at generally corresponding circumferential positions on skirt 22. In the preferred embodiment, lid 3 cannot be removed from body 2 along axis 15 while lid 3 is in its second rotational position. When lid 3 is completely turned into its second rotational position, lower tabs 28,29 substantially completely underlie upper wall 8 and first stop tabs 30 engage back surfaces 34 of first and second notches 13,14. 
     When lid 3 is raised sufficiently that bottom bearing surfaces 26 of upper tabs 23,24 are above upper face 10, lid 3 can be rotated from its second rotational position to its unsecured third rotational position. FIGS. 5 and 6 illustrate the preferred third rotational position. In that position, shoulder 21 is not parallel with upper face 10 and lid axis 16 is at an angle to opening axis 15. In that position, upper tabs 23,24 are supported by upper wall 8 by the engagement of bottom bearing surfaces 26 with upper face 10. Upper tabs 23,24 are located such that when lid 5 is supported by upper tabs 23,24, lid 5 is unbalanced and consequently tends to tilt in one direction. In the preferred embodiment of this invention, the lid is generally circular and symmetrical in top and bottom plan, and upper tabs 23,24 are both located on the same side of a centerline. Lid 5 is also supported by the engagement of flange 20 with upper wall 8. Because of the non-parallel relationship of shoulder 21 and upper face 10, and because lid axis 16 is offset from opening axis 15, the unsecured third rotational position of lid 3 is visually distinct from the secured first and second rotational positions. 
     FIG. 7 shows an alternative third rotational position. In that position, upper tabs 23,24 support lid 3 such that shoulder 21 is generally parallel to upper face 10 and opening axis 15 and lid axis 16 are co-axial. 
     When lid 3 is removed from body 2 and thereafter returned, lower tabs 28,29 may or may not be received by first and second notches 13,14, depending on whether lower tabs 28,29 are aligned with first and second notches 13,14 when lid 3 is placed on body 2. If notches 13,14 receive lower tabs 28,29, lid 3 will be supported in its third rotational position described above. Container 1 is adapted to support lid 3 in an unsecured fourth rotational position, illustrated in FIG. 12. In that position, support surfaces 27 of lower tabs 28,29 and flange 20 engage upper wall 8 to support lid 3 is an offset position in which shoulder 21 is in a non-parallel relationship to upper face 10. In the fourth rotational position, as in other rotational positions, skirt 22 extends into opening 9. 
     To facilitate the operation of the container of this invention, it is preferred that lid 3 be provided with an arm 38 and that upper wall 8 be provided with a corresponding slot 39 adapted to received arm 38. One purpose of arm 38 is to ensure that lid 3 cannot be removed from body 2 while lid 3 is in the first and second rotational positions. In the preferred embodiment, arm 38 projects from skirt 22 and comprises a lateral member 40 of generally the same dimensions as lower tabs 28,29, generally parallel to shoulder 21 and spaced from shoulder 21 at approximately the same distance as lower tabs 28,29. Arm 38 also comprises leg 41 between lateral member 40 and lower edge 42 of skirt 22. Also in the preferred embodiment, slot 39 comprises an opening in upper wall 8 substantially identical to first and second notches 13,14. It is preferred that first and second notches 13,14 and slot 39 be spaced at equal distances about the perimeter of upper wall 8, as illustrated in FIG. 2. It is also preferred that lower tabs 28,29 and arm 38 be spaced at equal distances about the perimeter of skirt 22, also as illustrated in FIG. 2. In that manner, each of first and second notches 13,14 and slot 39 can receive lower tabs 28,29 and arm 38, and lid 3 can be introduced onto body 2 in the third rotational position in any one of three orientations of lid 3 about opening axis 15. 
     In the first rotational position, arm 38 and lower tabs 28,29 underlie upper wall 8 at a distance, and upper tabs 23,24 secure lid 3 from substantial movement along opening axis 15. In the second rotational position, each of upper tabs 23,24 aligns with one of first and second notches 13,14 and slot 39, as illustrated in FIG. 10. In that position, arm 38 and lower tabs 28,29 underlie upper wall 8, as illustrated in FIG. 8, and prevent removal of lid 3 from body 2 by interfering with upper wall 8 as lid 3 is moved axially. In the third rotational position, illustrated in FIGS. 5 and 6, upper tabs 23,24 rest on upper wall 8 and each of lower tabs 28,29 and arm 38 underlies one of first and second notches 13,14 and slot 39. In the fourth rotational position, illustrated in FIG. 12, arm 38 underlies upper wall 8 and lower tabs 28,29 and flange 20 rest on upper wall 8. 
     Arm 38 enables lid 3 to assume a fifth rotational position, illustrated in FIG. 13. That position is similar to the fourth rotational position, except that arm 38 overlies upper wall 8 rather than underlies it. In the fifth rotational position, lid 3 is supported by the engagement of lower tabs 28,29 and leg 41 with upper wall 8. Underside 43 of leg 41 is located at a greater distance from shoulder 21 than the support surfaces 27 of lower tabs 28,29. Consequently, in the fifth rotational position shoulder 21 is in a non-parallel relationship to upper face 10. 
     In the preferred embodiment of this invention, second stop tabs 45 connect proximate end 46 of at least one of upper tabs 23,24 and adjacent end 47 of the corresponding lower tab 28 or 29. Second stop tabs 45 serve to facilitate the movement of lid 3 between the second, third and fourth rotational positions. As lid 3 is rotated from its second rotational position to its third rotational position, second stop tabs 45 engage back surfaces 34 to align lower tabs 28,29 with first and second notches 13,14. As lid 3 is further rotated in the same direction toward the fourth rotational position, second stop tabs 45 direct lower tabs 28,29 out of first and second notches 13,14 and onto upper wall 8. In a similar manner, when lid 3 is rotated in a reverse direction from its third rotational position, second stop tabs 45 engage front surfaces 33 to direct upper tabs 23,24 into first and second notches 13,14. 
     From the foregoing it is seen that in all unsecured positions of lid 3 on body 2--ie., in all positions of lid 3 on body 2 in which lower tabs 28,29 do not underlie upper wall 8--lid 3 is supported in an elevated position visually distinct from the positions in which lid 3 is secured to body 2. As is obvious from the foregoing, many alternative embodiments fall within the scope and intent of this invention. The following claims are intended to fully include all such embodiments.