TOP FRAME WITH LOCKING FEATURES

Abstract

A top frame with locking features is provided. The top frame includes four legs having a top surface and a bottom surface. The top frame includes a first interlocking feature in the form of a plurality of protrusions and a second interlocking feature in the form of indented receptacles on the top surface. The plurality of protrusions can be provided proximate a corner of the top frame and the plurality of indented receptacles can also proximate the corner but spaced from the plurality of protrusions. Each corner of the top frame can include a plurality of protrusions and a plurality of indented receptacles. Each occurrence of the plurality of protrusions and the plurality of indented receptacles can alternate about the top surface of the top frame. The bottom surface can also include the same pattern of locking features.

Description

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

N/A

FIELD OF THE INVENTION

The present invention is generally directed to a top frame with interlocking features to prevent slippage when shipped in stacks upon other like top frames, and more particularly, to a top frame having a plurality of projections and a plurality of indented receptacles that align with indented receptacles and projections, respectively, of a like top frame.

DESCRIPTION OF THE PRIOR ART

Top frames are used, along with other components—such as pallets, in the transportation industry to transport goods from one location to another. For example, top frames are part of a primary packaging product used in the beverage industry to distribute cans (e.g., drawn and ironed aluminum beverage cans) and bottles—typically loaded in stacks separated by slip sheets on a pallet. The top frame is placed on top of the stack and provides a rigid structure for engaging metal straps or bands, or other similar materials or structures, for securing the entire system together.

The top frames are typically used in a returnable loop system where they are returned to the manufacturer (after use) stacked together and shipped back in bulk pallet loads. One issue with this system is that when shipped in stacks, the frames tend to slide easily on one another making for a very unstable stack that is difficult to manage.

One solution proposed by Precision Thermoplastics Components, Inc. in U.S. Publication No. 2012/0285851 utilizes a cylindrical pocket that mates with a ramp that protrudes from the surface of the top frame. However, this system is difficult to align and requires the protrusion to extend a significant amount from the surface of the top frame.

Another solution, proposed by Rehrig Pacific Company, involves performing a secondary scuffing operation (i.e., after formation or molding of the top frame) to apply a texture to the surface and manipulate the surface friction of the frame (such as that shown for pallets in U.S. Pat. No. 7,216,415). However, this secondary scuffing operation can be messy and costly. Moreover, the scuffing is less effective over time.

The present invention provides a lasting locking mechanism to prevent slippage of stacked top frames without requiring strict alignment of the frames, or involve a messy and costly scuffing operation.

SUMMARY OF THE INVENTION

The present invention is directed to a top frame with locking features to prevent slippage when stacked on other like top frames. The locking feature uses several low profile protruding features that match up with a corresponding mirrored pattern of indented receptacles that locks top frames together, preventing them from sliding off one another. The locking features do not have to be perfectly aligned in order to function properly. The number of receptacles can be made larger than the number of protruding features such that two top frames can be shifted slightly with respect to each other in the stack and still be locked together. That is, the teeth (i.e., protruding features) can still engage the receptacles when the top frames are slightly misaligned and shifted off each other for easier stacking. The protruding features and indented receptacles are oriented on each corner (on both sides of each top frame) so the top frames can be stacked in any configuration. There is no specific top or bottom surface or end to the frames that require orientation for frames to lock.

In accordance with one aspect of the present invention, a top frame is provided with interlocking features. The top frame comprises a first leg, a second leg, a third leg, and a fourth leg to form a generally rectangular structure or shape with a generally rectangular central opening. The top frame includes an upper surface and an opposing lower surface. The top frame also includes a first locking feature in the form of a first plurality of repeating protruding structures positioned at a first location on the upper surface of the top frame. The top frame further includes a second locking feature in the form of a first plurality of repeating indented receptacles at a first location on the lower surface of the top frame. The first locking features of one top frame are designed to mate with or engage the second locking features of a second like top frame, and so on in a stack of top frames.

The first location of the first plurality of repeating protruding structures can be proximate a first corner of the top frame. Similarly, the first location of the first plurality of indented receptacles can be proximate the first corner of the top frame and aligned with the first plurality of repeating protruding structures.

The first plurality of repeating indented receptacles can be a mirrored pattern of the first plurality of repeating protruding structures. That is, the receptacles can have a conforming shape to that of the protrusions. In some preferred instances, the number or amount of the first plurality of repeating indented receptacles is greater than a total number or amount of the first plurality of repeating protruding structures. In these instances, the top frames can be offset with respect to each other and still be able to accommodate all of the protrusions to lock the frames and prevent slippage.

The top frame can also comprise a second plurality of repeating protruding structures positioned proximate a second corner of the top frame on the lower surface of the top frame and a second plurality of repeating indented receptacles positioned proximate the second corner of the top frame on the upper surface of the top frame and aligned with the second plurality of repeating protruding structures. In fact, each of the top surface and the lower surface can have alternating sets of a plurality of protrusions and a plurality of receptacles at each corner.

The first plurality of repeating protruding structures can have a saw-tooth cross-sectional shape. Similarly, the first plurality of indented receptacles can have a saw-tooth cross-sectional shape.

The top frame can be formed from a molded plastic in two pieces. Each piece includes a flat outer surface and a plurality of ribs extending from the outer surface. The two pieces are welded together so that the ribs extend between each of the flat outer surfaces.

In accordance with another aspect of the invention, a top frame with interlocking features comprises a first leg having a first end and a second end, a second leg connected at a first end to the second end of the first leg, a third leg connected at a first end to a second end of the second leg and a fourth leg connected at a first end to a second end of the third leg and connected at a second end to the first end of the first leg. The first leg, second leg, third leg and fourth leg have an upper surface and a plurality of ribs extending downward from the upper surface. The top frame includes a first plurality of ridges extending upward from the upper surface at a first location and a first plurality of receptacles extending downward from the upper surface at a second location. The first location can be proximate a first corner of the top frame formed by the first leg and the second leg, and the second location can be proximate the first corner and spaced from the first location.

Additionally, the top frame can include a second plurality of ridges extending upward from the upper surface proximate a second corner formed by the second leg and the third leg and a second plurality of receptacles extending down from the surface proximate the second corner and spaced from the second plurality of ridges. The first plurality of ridges can have a saw-tooth cross-sectional shape and the first plurality of receptacles can also have a saw-tooth cross-sectional shape.

The top frame can include a second component having a fifth leg having a first end and a second end, a sixth leg connected at a first end to the second end of the fifth leg, a seventh leg connected at a first end to a second end of the sixth leg and an eighth leg connected at a first end to a second end of the seventh leg and connected at a second end to the first end of the fifth leg. Like the first component described above, the fifth leg, sixth leg, seventh leg and eighth leg have a lower surface and a plurality of ribs extending from the lower surface. The ribs from the lower surface are welded to the plurality of ribs extending downward from the upper surface. The lower surface can include a first plurality of ridges extending downward from the lower surface at a first location and a first plurality of receptacles extending upward from the lower surface at a second location.

Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

To understand the present invention, it will now be described by way of example, with reference to the accompanying drawings in which:

FIG. 1 is an upper perspective view of two stacked top frames having interlocking features in accordance with the present invention;

FIG. 2 is an enlarged perspective view of a corner portion of the stacked top frames of FIG. 1;

FIG. 3 is an enlarged perspective view of a plurality of protrusions in accordance with an aspect of the present invention;

FIG. 4 is an enlarged perspective view of a plurality of indented receptacles in accordance with an aspect of the present invention;

FIG. 5 is a cross-sectional view of the locking features of a first top frame and a second frame in a first configuration;

FIG. 6 is a cross-sectional view of the locking features of a first top frame and a second frame in a second configuration; and,

FIG. 7 is a perspective view of a lower portion of half of a top frame.

DETAILED DESCRIPTION

While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.

FIG. 1 is a perspective view of an upper top frame 10 stacked on a lower top frame 10′ in accordance with the present invention (only the very edge of the lower top frame 10′ is visible in this Figure). The upper top frame 10 is generally rectangular with slightly rounded corners and includes a first leg 12, a second leg 14, a third leg 16 and a fourth leg 18 (the lower top frame 10′ is identical to the upper top frame 10). The legs 12, 14, 16, 18 are connected at their ends to form four corners and define a generally rectangular central opening 20 (in some embodiments, the top frames can include cross beams and other structures extending between the legs in the opening). The top frame 10 includes a generally planar upper surface 22 and a corresponding lower surface (which, in the configuration of this Figure would be in contact with the upper surface of the lower top frame 10′). The top frame 10 is preferably formed from a molded plastic in two parts that are welded together to form a rigid member for facilitating transportation of goods such as stacks of beverage cans or bottles on a pallet. The frame allows for metal bands or straps to be tensioned around the top frame, pallet and stacks of beverage cans or bottles (or other goods transported supported on the pallet).

Each corner of the top frame 10 includes a first locking feature in the form of a plurality of repeating protrusions 24 extending upward from the top surface 22 of the top frame 10, and a second locking feature in the form of a plurality of repeating indented receptacles 26 extending downward from the planar portion of the upper surface 22. The first locking features and second locking features are arranged so that they alternate around the upper surface 22 of the top frame 10. This means that each leg has one of the plurality of protrusions 24 at one end and one of the plurality of indented receptacles 26 at the other end. While only the top surface 22 is shown in FIG. 1, a bottom surface of the top frame 10 will include essentially the same pattern of alternating first locking features 24 and second locking features 26 proximate the corners of the top frame 10.

The plurality of repeating protrusions 24 and the plurality of repeating indented receptacles 26 are shown in greater detail in FIGS. 3 and 4, respectively. In the example provided in FIG. 3, the plurality of repeating protrusions 24 includes four generally triangular (in cross-section) protrusions 28 in a row slightly spaced from one another by flat segments 30. Similarly, the plurality of repeating indented receptacles 26 includes six receptacles 32 where each receptacle 32 is configured to mate with or receive one of the protrusions 28.

As evident in FIGS. 3 and 4 there is a greater number of receptacles 32 in each plurality of repeating indented receptacles 26 than protrusions 28 in each plurality of repeating protrusions 24. This allows for a slight misalignment of the two structures and still have an interlock between the top frames. For example, as illustrated in the cross-sectional view of FIG. 5, the four protrusions 28 on the lower top frame 10′ are positioned in the middle receptacles 32 of the upper top frame 10 such that there is an empty receptacle 34 on each side of the plurality of protrusions 24. In the cross-sectional view of FIG. 6, the bottom top frame 10′ is in a slightly different position with respect to the upper top frame 10 such that both empty receptacles 34 are at one end of the four protrusions 28. While the number of protrusions and receptacles are shown as being four and six, respectively, each could be more or less as desired for a particular size of the top frame or a particular size of the protrusions/receptacles.

In addition to allowing some misalignment between the top frames in view of the additional receptacles, the size of the protrusions with respect to the receptacles can be chosen to provide for misalignment along their lengths. That is, the length of each protrusion 28—from one end to the other—can be significantly less than the length of each receptacle 32—from one end to the other—providing room for misplacement along the length direction.

As illustrated in FIGS. 5 and 6, the plurality of protrusions 24 and the plurality of indented receptacles 26 each have a saw-tooth (or a slightly spaced saw-tooth) configuration. The cross-sectional design can also be chosen to have other similar repeating configurations.

Each of the top frames 10 in accordance with the present invention are formed from two identical halves that are welded together. FIG. 7 shows the bottom of a half 36 of a top frame 10 (the other surface—not shown here—would be identical to surface 22 as illustrated in FIG. 1). The half 36 includes a plurality of ribs 38 that extend from a planar surface. The ribs 38 are welded to ribs 38 of another half 36 to form a complete top frame 10 having an upper surface and an identical lower surface. In some instances, only a half 36 of the top frame may be needed. In which case two can be stacked on each with the support surfaces facing each other to engage the locking features.

As used herein, directional terms—such as top, bottom, upper, lower, etc.—are used with respect to the top frames, or portions thereof, as shown or positioned in the drawings, and are not meant to limit the scope of the invention or require the top frame to remain in that position. For example, an upper surface would still exist if the top frame was moved upside down.

Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood within the scope of the appended claims the invention may be protected otherwise than as specifically described.

Claims

1. A top frame with interlocking features comprising: a first leg;a second leg;a third leg;a fourth leg, wherein the first leg, second leg, third leg and fourth leg form a generally rectangular shape having an upper surface and an opposing lower surface;a first plurality of repeating protruding structures positioned at a first location on the upper surface of the top frame; and,a first plurality of repeating indented receptacles at a first location on the lower surface of the top frame.

2. The top frame of claim 1 wherein the first location of the first plurality of repeating protruding structures is proximate a first corner of the top frame.

3. The top frame of claim 2 wherein the first location of the first plurality of indented receptacles is proximate the first corner of the top frame and aligned with the first plurality of repeating protruding structures.

4. The top frame of claim 3 wherein the first plurality of repeating indented receptacles is a mirrored pattern of the first plurality of repeating protruding structures.

5. The top frame of claim 3 further comprising: a second plurality of repeating protruding structures positioned proximate a second corner of the top frame on the lower surface of the top frame; and,a second plurality of repeating indented receptacles positioned proximate the second corner of the top frame on the upper surface of the top frame and aligned with the second plurality of repeating protruding structures.

6. The top frame of claim 1 wherein the first plurality of repeating protruding structures has a saw-tooth cross-sectional shape.

7. The top frame of claim 1 wherein a total amount of the first plurality of repeating indented receptacles is greater than a total amount of the first plurality of repeating protruding structures.

8. The top frame of claim 1 wherein the top frame includes a plurality of ribs extending from the upper surface to the lower surface.

9. The top frame of claim 1 wherein the first leg, second leg, third leg and fourth leg define a generally rectangular opening therebetween.

10. The top frame of claim 5 further comprising: a third plurality of repeating protruding structures positioned proximate a third corner of the top frame; and,a first plurality of repeating indented receptacles positioned proximate the third corner of the top frame.

11. The top frame of claim 10 further comprising: a fourth plurality of repeating protruding structures positioned proximate a fourth corner of the top frame; and,a fourth plurality of repeating indented receptacles positioned proximate the fourth corner of the top frame.

12. The top frame of claim 2 further comprising a second plurality of repeating indented receptacles on the upper surface proximate the first corner and proximate the first plurality of repeating protruding features.

13. The top frame of claim 1 formed from a molded plastic.

14. A top frame with interlocking features comprising: a first leg having a first end and a second end;a second leg connected at a first end to the second end of the first leg;a third leg connected at a first end to a second end of the second leg;a fourth leg connected at a first end to a second end of the third leg and connected at a second end to the first end of the first leg; the first leg, second leg, third leg and fourth leg having an upper surface;a first plurality of ridges extending upward from the upper surface at a first location; and,a first plurality of receptacles extending downward from the upper surface at a second location.

15. The top frame of claim 14 further comprising a plurality of ribs extending downward from the top surface.

16. The top frame of claim 14 wherein the first location is proximate a first corner of the top frame formed by the first leg and the second leg, and the second location is proximate the first corner and spaced from the first location.

17. The top frame of claim 16 further comprising: a second plurality of ridges extending upward from the upper surface proximate a second corner formed by the second leg and the third leg; and,a second plurality of receptacles extending down from the surface proximate the second corner and spaced from the second plurality of ridges.

18. The top frame of claim 14 wherein the first plurality of ridges has a saw-tooth cross-sectional shape, and the first plurality of receptacles has a saw-tooth cross-sectional shape.

19. The top frame of claim 15 further comprising: a fifth leg having a first end and a second end;a sixth leg connected at a first end to the second end of the fifth leg;a seventh leg connected at a first end to a second end of the sixth leg;an eighth leg connected at a first end to a second end of the seventh leg and connected at a second end to the first end of the fifth leg; the fifth leg, sixth leg, seventh leg and eighth leg having a lower surface and a plurality of ribs extending upward and welded to the plurality of ribs extending downward from the upper surface;a first plurality of ridges extending downward from the lower surface at a first location; and,a first plurality of receptacles extending upward from the lower surface at a second location.

20. The top frame of claim 14 wherein the top frame is formed from a molded plastic.