Patent Application
20140263885
1. Field of the Invention
The present invention concern containers used for holding materials which are supported above the ground by support feet. More particularly, it is concerned with an interlocking support foot adapted for mounting to the bottom of such containers whereby loosening of the support foot is resisted by an interlocking feature, as well as a corresponding method of supporting such a container on support feet.
2. Description of the Prior Art
Containers are often employed to hold materials such as liquids or particulate matter until they are ready to be dispensed for use. Oftentimes it is desirable to elevate the main portion of the container above a floor or other supporting surface for ease of cleaning, for permitting lifting mechanisms such as fork lifts to place their tines beneath for lifting, and for ease of dispensing the contents of the container. In such circumstances, support feet may be coupled to the container.
An example of the use of support feet with a container, in particular a fluid tank, is shown in U.S. Pat. No. 6,484,899, the entire contents of which are incorporated herein by reference. There, a rotationally molded tank includes support columns which include threaded recesses for mounting support feet thereto. The support feet are threaded into the recesses and serve to elevate the container above a supporting surface. The support feet which can be threadably attached is a structural feature which takes the place of a rotationally molded base.
The present invention provides a significant advance over the assembly shown in the U.S. Pat. No. 6,484,899 in that it provides support feet which resist loosening or, in the extreme, detachment from the container. Loosening of the support feet connection with the container may result in uneven support of the container, which places greater stress on some areas of the container when it is filled. The present invention overcomes this problem by providing structure in the form of one or a plurality of teeth on the support feet which engages a corresponding support area on the tank when the support foot is fully mounted. This engagement prevents loosening of the foot and thus provides a stable support connection between the container and the support foot.
In greater detail, the support foot of the present invention may include a body having an upper surface, a connector which extends upwardly from the upper surface and having a helical thread, and at least one tooth spaced radially outwardly from the connector and projecting upwardly from the upper surface. The connector, the at least one tooth, or preferably both are unitary with the body, and the support foot may be molded of synthetic resin. The helical thread may be an external helical thread, and the body may be circular when viewed in horizontal cross section. The tooth may be provided with an upright end wall and a sloped wall. The sloped wall may be longer than the upright wall, and may extend upwardly from the upper surface to a peak where it intersects with the upright wall. The sloped wall is preferably oriented to extend generally perpendicular to a radial line extending outwardly from the center of the connector, and to incline upwardly from the upper surface to the peak whereby the tooth has progressively greater engagement with the container as the support foot is threaded onto a corresponding support area of the container. In this way, the upright wall of the tooth may engage the container to resist reverse rotation of the support foot which would tend to otherwise loosen it from the container. More preferably, a plurality of such teeth are positioned in a circular array along the upper surface. The array may include a plurality of such teeth, with their slopes in a common circular orientation, and placed end to end. A relatively flat, annular supporting surface may be located between the connector and the array.
The support foot may beneficially be used in combination with a container having one or a plurality of complementally configured support areas. The support areas may be provided with a threaded receiver, for example an internally threaded receiver, complementally configured to threadably receive the helical thread of the connector. The support areas may be unitary with the container, and molded of synthetic resin. The support areas may be provided with at least one notch which extends downwardly from the surrounding portion of the support area. The notch may have an upright surface and a sloped surface oriented so that the sloped wall of the foot support slides over the sloped surface during installation and tightening of the support foot. There may be a plurality of such notches provided in spaced circular arrangement as a locking ring, so that one or more of the teeth may engage one or more of the notches. An annular flat bottom surface may be provided between the array and the threaded receiver and positioned opposite the annular flat support surface of the support foot.
The invention hereof may further include a method of supporting a container on one or more of such support feet. The connector of the support feet may be inserted into a respective one of the threaded receivers, and rotated. This will result in threading of the support foot onto the container, bringing the tooth into engagement with the support area. As a result of the orientation of the sloped wall of the support foot, the support foot will then progressively bring the tooth into further engagement with the support area, and the peak of the tooth will then resist loosening of the support foot on the container's support surface. Preferably, the provision of one or more notches, which have a sloped surface and a downwardly extending upright wall which are opposite the orientation of the corresponding sloped wall and upright wall of the teeth, will result in the upright wall of the teeth being blocked from reverse rotation by the upright surface of the notches. Thus, by tightening the support foot on the support area of the container, the support foot will retain this tightened position. Most preferably, this will also result in the flat annular support surface being in engagement with the opposite flat, annular bottom surface of the container for improved support of the container by the support foot.
Referring now to the drawing, a container assembly 10 broadly includes a container 12 for holding materials such as liquids or particulate matter and a plurality of support feet 14. As set forth in U.S. Pat. No. 6,484,899, the entire disclosure of which is incorporated herein by reference, the container 12 may be rotationally molded of a synthetic resin material such as high density polyethylene and may have a central tank section and support columns 16 at its corners. The container 12 may be unitary and be provided with a bottom section 18 having support areas 20, the support areas 20 in the preferred embodiment being located at the bottom of the support columns 16.
The support feet 14 are complementally configured to be coupled with the container 12 as shown in
In greater detail, the body 22 may have an outer wall 28, the exterior of which is circular when viewed in plan and be provided with a plurality of interior, radially inwardly oriented intersecting ribs 30. Other wall configurations may be utilized and thus it may be appreciated that the body 22 could be polygonal (e.g., square) or of other configurations when viewed in plan. The ribs 30 provide a web-like interior structure reinforcement and support and lessen the quantity of material required for the support feet 14. The ribs 30 preferably extend upwardly through the body 22 and extend into the interior of the connector 24 as shown in
The connector 24 extends upwardly from the upper surface 32. Preferably, the connector 24 is generally cylindrical in shape and provided with an external helical thread 34. The thread 34 is most preferably a fine thread with a small pitch, such that an increased number of thread surfaces engage the support area 20 of the container 12. As illustrated in
At least one, and preferably a plurality of teeth 26 are spaced radially outwardly of the connector 24 on the upper surface 32 of the support foot 14. The teeth 26 extend upwardly from the upper surface. Most preferably, the teeth 26 are provided in an array 35 extending in a circular pattern surrounding the connector 24 as shown in
The support surface 20 of the container 12 is preferably complementally configured to receive and mount a support foot 14 thereon. The support surface 20, as best seen in
In use, a plurality of support feet 14 corresponding to the number of support areas 20 of the container 12 are provided. The connector 24 of each support foot 14 is inserted into the corresponding threaded receiver 48 such that the helical thread 34 mates with and engages the helical flight of the threaded receiver 48 and the support foot 14 is then rotated until the teeth 26 come into engagement with the support area 20. Because the sloped surface 56 is complemental and opposite the sloped wall 46, and because the notches 52 and teeth 26 are preferably of synthetic resin and thus slightly yield, the support foot 14 may be further rotated and tightened. Here, the peak 44 of the teeth 26 should engage the support area 20 of the container 12 and thus “dig in” to the synthetic resin to resist reverse rotation. Moreover, where the connector has a right hand helical thread 34, further clockwise rotation of the support foot 14 should result in a locking condition as shown in
Although preferred forms of the invention have been described above, it is to be recognized that such disclosure is by way of illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention.
The inventor hereby states his intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of his invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims.
