Container or can bottom
United States Patent Knize Apr. 22, 1975 CONTAINER OR CAN BOTTOM [57] ABSTRACT [75] inventor: Elmer Knize Chicago A can or container having a bottom formed with a [73] Assignee: Lippy Can Co., Ltd., Chicago. lll. central convexo-concave portion which continues I downwardly at its peripheral edge to form a bend and [22] Filed then extends upwardly in a substantial vertical plane [21] Appl. No.: 316,824 to substantially the height of the top horizontal plane of the convexo-concave central portion and then continues outwardly and downwardly and is secured to &#39;1 8 the body of the container. This shape of the bottom is [58] 770/67 C I F maintained until the container is occupied with conle 0 d tents and when the lid is applied to the top of the container the air will be trapped in the container and the compressed air together with the contents will cause [56] References cued the annular convexo-concave portion to bulge down- UNITED STATES PATENTS wardly and form a concave or concavo-convex dish 1.672.839 6/1928 Ruttan 1 220/97 R shaped annular central portion, and when the con- 2.2 5.685 6/194 Con er 206/508 tainer receives a shock, such as when striking against s&#39; ls f v v 2556; a surface, the central concavo-convex bottom will 21 man 1 1,288,342 ll/1966 Tinker 220/97 R bulge further outwardly extend below the bottom Primary E.\&#39;an1inerWilliam 1. Price Assistant E.\&#39;aminerAllan N. Shoap Attorney. Agent, or FirmMax R. Kraus horizontal plane of the bottom of the container. The said structure also permits the can to be stacked on other cans in an interlocking relationship.  
 7 Claims, 5 Drawing Figures 1 CONTAINER OR CAN BOTTOM BRIEF SUMMARY OF THE INVENTION An object of this invention is to provide a preformed bottom for a container or can wherein the bottom has a convexo-concave central portion spaced from the body of the container, with the portion intermediate between the body and the central portion so constructed as to form a generally U-shaped confirguration. When the container is filled with contents and air is trapped in the container when the lid is applied thereto, the central convexo-concave portion will bulge downwardly to form a concavo-convex dishshaped configuration. The last mentioned configuration will be further deformed when the container is subjected to shock, such as when falling against a surface. and in that instance the central concavoconvex bottom will bulge further outwardly.  
  Another object of this invention is to provide a bottom for a container or can which is shaped so that it can be stacked on the top of an adjacent container and will be locked in stacked position.  
 BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:  
  FIG. 1 is an elevational view of the bottom of the can forming this invention and showing in dotted lines another can on which it is stacked.  
  FIG. 2 is an enlarged cross-sectional view taken on line 2-2 of FIG. 1, showing the bottom of the can in the position when the can is empty.  
  FIG. 3 is a sectional view, similar to FIG. 2, but showing the position of the bottom of the can when the can is filled with contents such as paint or the like and the cover or lid has been applied on the can.  
  FIG. 4 is a view similar to FIG. 3 when the can is filled, but showing the bottom in the position when the can absorbs a shock, such as when the can is dropped or when the side of the can strikes against an object; and  
  FIG. 5 is a sectional view taken on line 5-5 of FIG. 1, showing the stacking of two cans.  
 FIGS. 1 THROUGH 4 Referring first to FIGS. 1 to 4 inclusive, the can or container, generally indicated at 10, is formed preferably of metal and includes a circular body 12 and a bottom generally indicated at 14 which is likewise formed of metal and which is secured to the body 12 as at 16. The structure and configuration of the bottom in relation to the body forms the subject matter of this application. The top of the can is closed by a lid, to be subsequently described.  
  The bottom 14 of the can is initially formed to the shape and configuration shown in FIG. 2 and when secured to the body the bottom, when the can is empty, will be shaped as shown in FIG. 2. The bottom 14 is of circular shape and comprises a main central annular convexo-concave or inverted dish-shaped portion 17 which continues at its peripheral edge 18 with a short annular downwardly outwardly inclined wall 19 which continues to form a curved bend 20 which is defined as the lower bend and which then continues upwardly to form a spaced short vertical wall 22 which then curves as at 23 and is defined as the upper bend, and then continues downwardly as at 24 at an inclined plane and then continues vertically downward as at 26 and then curves around as at 27 and continues upwardly as at 28 and then curves around inwardlly as at 29 and continues vertically downward as at 30 and curves around and extends upwardly as at 32 so that the bottom of the body 12 of the can which has its bottom edge turned upwardly as at 34 and then downwardly and inwardly as at 36 is interlocked with the bottom 14 of the can. Thus, the bottom of the can is permanently secured to the body 12. The central annular portion 17b of the main central dish-shaped portion 17 is further upwardly recessed, as best shown in FIG. 2, and the recessed portion is upwardly of the dish-shaped portion 17.  
  The bottom 14 of the can therefore comprises a generally convexo-concave central annular portion 17 with the peripheral portion of a generally U-shaped annular configuration, generally designated by the numeral 25, formed by the walls 19, 22 and bend 20, with the top of the wall 22 bending outwardly and continuing to form an annular downwardly sloping surface 24 between the body of the can and the central convexconcavo portion 17 of the bottom 14. As can be seen, the upper and lower bends 23 and 20 are on different horizontal planes.  
  When the can is filled with paint or other material and the lid is placed over the top of the can to cover the can opening, a certain amount of air will be trapped at the top and compressed and this added to the weight of the material in the can will cause the bottom of the can, particularly the central convexo-concave portion 17 to bulge downwardly and assume the position shown in FIG. 3, wherein the convexo-concave portion 17 as sumes a concave-convex shape, indicated at 17&#39;, as shown in FIG. 3. The central annular recessed portion 17b still remains generally recessed, as shown in FIG. 3. The reshaping or deformation of the central portion 17 of the can thus equalizes the pressure inside the can. In effect, the reshaping and the deformation of the central portion serves in the nature of a spring or resilient member against which pressure is applied. It should be noted that when the central concavo-convex portion 17&#39; of the can assumes the shape shown in FIG. 3, the lowermost portion thereof is still within the horizontal plane of the bottom of the can and the recessed portion 17b is inwardly and upwardly of the bottom horizontal plane. Thus, when the filled cans are stacked, the recessed portion 17b would not contact the lid of the can positioned therebelow.  
  The peripheral annular U-shaped portion surrounding the central concave-convex portion 17 of the bottom serves to perform a necessary function, particularly when the can is subjected to shock, as when the body of the can strikes another object or falls on either its side or bottom when being handled. Under such a condition the bottom of the can is further deformed and assumes the shape shown in FIG. 4, in which the annular peripheral U-shaped portion 25 tends to straighten out so that the bend 20 and the wall 19 form a downwardly inclined wall 38 which merges with the central annular concave portion and the bottom portion of the thus reshaped bottom will extend below the horizontal plane of the bottom of the can body. After the shock has been absorbed by the can the bottom of the can will return to the shape shown in FIG. 3. It is only when the can is subjected to a shock that the configuration of the bottom assumes the shape shown in FIG. 4.  
  The bottom of the can also has the additional advantage in that the can can be stacked in a locked position with respect to other cans having a top and a lid, as shown in FIG. 5. The lower can generally indicated at 40 has a rim generally indicated at 42 and a lid or cover generally indicated at 44 applied thereto and same forms the subject matter of a copending application which matured into US. Pat. No. 3,799,388 issued Mar. 26, 1974 and will be briefly described.  
  The rim 42 is of circular shape and is formed to comprise an inner vertical wall 46 which terminates at its lower end in an inner rolled bead 47. The upper portion of the vertical wall 46 of the rim is curved or arcuateshaped to form a rolled top surface 48 which continues downwardly, with the outer spaced vertical wall 49 angled or inclined outwardly at the bottom as at 50 and which continues laterally with a horizontal bottom section 52 which continues vertically upwardly to form a spaced vertical wall 53 which then continues outwardly to form a rolled top surface 54 to receive therewithin the rolled upper edge 56 of the body 58 of the con tainer 40.  
  The lid 44 is of circular shape and comprises a main central concave or dish-shaped portion 60 which continues upwardly to an annular peripheral edge 62 and then continues with an annular downwardly sloping short peripheral wall portion 63, the bottom of which is rounded as at 64, and then continues upwardly to form a vertical wall 66 which is rounded and slopes upwardly and outwardly at the top as at 67 and then continues in a downward outer vertical wall 68 and terminates in a curled edge 69. The walls 66, 68 and top 67 form an inverted U-shaped configuration on the lid which seats on and engages the inverted U-shaped portion of the rim and secures the lid to the rim of the container in a positive manner, all as more specifically described in my copending application.  
  The bottom 14 of the upper can, which forms this invention, is adapted to be stacked on that type of rim and lid, as more clearly shown in FIG. 5. In this stacking position the curved portion 23 of the bottom of the can is positioned to rest on the rolled over portion 67 of the lid and the short vertical wall 22 of the bottom is positioned adjacent the vertical wall 66 of the lid. The downwarly sloping annular portion 24 of the bottom extends into and across the spaced opening between the vertical wall 68 of the lid and the vertical wall 53 of the rim. The central concavo-convex portion 17&#39; of the bottom extends over the concavo-convex portion 60 of the lid 44 and would be positioned in a spaced relation from the top of the lid, as best seen in FIG. 5.  
 What is claimed is:  
  1. A container and a bottom for said container, said bottom having a central annular convexo-concave central portion having an annular peripheral edge, said central portion continuing from its peripheral edge with a generally U-shaped annular portion comprising a downwardly extending inner wall at the peripheral edge of said central portion, a first bend formed between said peripheral edge and said inner wall, a curved bend an upwardly extending outer wall spaced from the inner wall, with the upwardly extending outer wall continuing outwardly in a curved bend and sloping downwardly to form a downwardly inclined annular wall and with the outer edge of said bottom being secured to the body of the container and spacing said U- shaped annular portion inwardly of the body of the container, said last mentioned curved bend forming a second bend between said upwardly extending outer wall and said downwardly inclined annular wall, said second bend being on a horizontal plane above said first bend.  
  2. A structure as set forth in claim 1 in which when the container is filled with contents and the lid is placed thereon for sealing said container, the pressure inside the can is equalized and the convexo-concave central portion assumes a concave configuration.  
  3. A structure as set forth in claim 2 in which when the can strikes an object the shock will be absorbed by the bottom of the can so that the annular inner wall of the U-shaped annular portion is caused to incline downwardly from the outer wall and form with said central concave bottom a continuing downwardly inclined wall.  
  4. A structure as set forth in claim 1 in which the second bend of the bottom seats on a raised portion of the lid of a lower positioned container so that the containers are vertically alined and interlocked in a stacked relationship.  
  5. A structure as set forth in claim 1 in which the inner wall of the U-shaped portion is shorter than the height of the outer wall of said U-shaped portion, and in which said inner wall is at an inclined outwardly sloping angle with said outer wall being substantially vertical.  
  6. A structure as set forth in claim 1 in which the top of the outer wall of the U-shaped portion is on substantially the same horizontal plane as the center of said convexo-concave central portion.  
  7. A structure as set forth in claim 1 in which the convexo-concave bottom has a central annular recessed portion which is recessed upwardly and is on substantially the same horizontal plane as the top of the outer wall of the U-shaped portion.  
  UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENTNQ: 3,878,963 DATED April 22, 1975 INVENTOR(S) I ELMER J. KNIZE It is oertrfied that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below- Claim 1, line 9, after &#34;bend&#34; insert --and--.  
 Signed and sealed this 1st day of July U375.  
  C. MARSHALL DANN RUTH C. Iii-130R Commissioner of Patents Attesting Officer and Trademarks