Protective device for shipping container corner castings

Abstract

A protective device for installation on a corner casting of a shipping container, the corner casting having a lower wall and an aperture. The protective device includes (a) a base, with an upper surface configured for engagement with the lower wall and a lower surface configured for engagement with a ground surface to provide a barrier between the corner casting and the ground surface, (b) an inner component sized and configured for insertion through the aperture, and (c) connection means for connecting the base to the lower wall of the corner casting. The connection means preferably comprise the inner component being rotatable between first and second configurations; in a first configuration, the inner component is rotated into an aligned orientation aligned with the aperture to allow insertion of the inner component into the corner casting interior; in a second configuration, the inner component is rotated into a misaligned orientation disallowing passage of the inner component back out through the aperture, such that the inner component engages the lower wall from within the corner casting while the base is retained against the outside of the lower wall to provide the barrier.

Description

FIELD OF THE INVENTION

[0001] The present invention relates to shipping containers, and specifically a load-distributing protective device or “shoe” designed for use with corner castings.BACKGROUND OF THE INVENTION

[0002] Shipping containers are commonly handled with heavy machinery and moved across diverse surfaces such as concrete, asphalt, metal, gravel, crushed stone, dirt, and other natural or artificial materials. The steel corner castings of shipping containers, which are integral to their structural strength and lifting capability, serve as the primary contact points during loading and unloading operations during which the corner castings engage the ground surface. This contact with abrasive surfaces frequently results in wear on both the containers and the unloading surfaces, often leading to significant damage over time. Addressing such damage can incur substantial costs, with infrastructure repairs related to the movement and handling of containers amounting to millions of dollars annually.

[0003] Existing solutions in the prior art have predominantly focused on protecting handling equipment, such as tow trucks, from damage caused by containers. However, these approaches often overlook the wear and degradation sustained by ground surfaces and infrastructure due to contact with the corner castings of shipping containers. Temporary measures, including rubber mats, wooden blocks, and steel plates, are susceptible to misplacement and typically fail to distribute the container's weight effectively. As a consequence, concentrated pressure points at the corner castings of a shipping container can exacerbate surface damage, limiting the practicality of these methods for long-term use.SUMMARY OF THE INVENTION

[0004] The present invention is a novel corner casting protective device or “shoe”, which is specifically designed for attachment to the corner castings of shipping containers. Shoes according to the present invention may enhance the handling, stability, and durability of shipping containers. This invention may mitigate damage inflicted on unloading surfaces, reduce surface abrasion, and distribute the load more effectively than traditional container handling methods. By affixing the present invention directly to the container's corner castings, the present invention may serve as a low-friction, durable interface between the container and the unloading surface, safeguarding against the costly surface wear and tear commonly associated with container handling.

[0005] The present invention may also enhance the versatility and ease of container modifications. Exemplary embodiments of the present invention are preferably constructed from a durable material characterized by exceptional strength, abrasion resistance, and low-friction properties. The selected material is preferably chosen to have a high load-bearing capacity and includes features that enhance its wear resistance. However, the chosen material may be sacrificial to some extent in certain embodiments.

[0006] In exemplary embodiments, the material may include, but is not limited to, ultra-high-molecular-weight polyethylene (UHMWPE), other polymer-based materials, or composite materials with similar properties. These materials are intended to enable embodiments of the present invention to withstand significant mechanical stress while facilitating smooth movement over various surfaces, thereby minimizing potential damage to unloading areas such as concrete, asphalt, and paving stones.

[0007] The materials are preferably chosen to maintain low friction even under substantial pressure, enabling the container to slide more smoothly during loading, unloading, or movement across surfaces, thus reducing friction and preventing damage to both the container and the contact surface.

[0008] In some exemplary embodiments, an expanded footprint is provided that exceeds the surface area of standard ISO corner castings, helping to ensure that the container's weight is distributed over a larger footprint and decreasing the psi (pounds per square inch) exerted on unloading surfaces. This feature may be particularly beneficial for delicate or high-cost surfaces, including concrete, decorative concrete, paving stones, asphalt, and other specialized materials, which are vulnerable to damage from abrasion or concentrated loads.

[0009] According to a first broad aspect of the present invention, there is provided a protective device for installation on a corner casting of a shipping container, the corner casting comprising walls defining an inner cavity, the walls comprising a lower wall, the lower wall having an upper face and a lower face and including an elongate aperture therethrough, the protective device comprising:

[0010] a base having upper and lower surfaces, the upper surface configured for engagement with the lower face of the lower wall of the corner casting, and the lower surface configured for engagement with a ground surface to provide a barrier between the corner casting and the ground surface;

[0011] an inner component sized and configured for insertion through the elongate aperture; and

[0012] connection means for connecting the base to the lower face of the lower wall of the corner casting.

[0013] In some exemplary embodiments, the connection means comprise the inner component being rotatable between first and second configurations:

[0014] wherein in the first configuration the inner component is rotated into an aligned orientation aligned with the elongate aperture to allow insertion of the inner component therethrough into the inner cavity; and

[0015] wherein in the second configuration the inner component is rotated into a misaligned orientation disallowing passage of the inner component out of the inner cavity through the elongate aperture, such that the inner component engages the upper face of the lower wall and the base is retained against the lower face of the lower wall to provide the barrier.

[0016] In some exemplary embodiments, the corner casting further comprises a side wall comprising an access aperture, the access aperture allowing access to the inner component in the inner cavity for rotation of the inner component between the aligned and misaligned orientations.

[0017] The inner component preferably comprises at least one laterally extending end and is shaped so as to pass freely through the elongate aperture when in the aligned orientation, wherein in the misaligned orientation the at least one laterally extending end engages the upper face of the lower wall to prevent passage of the inner component back through the elongate aperture.

[0018] In some exemplary embodiments the inner component is rotatable relative to the base, allowing rotation of the inner component within the inner cavity while the base is aligned with the lower face of the lower wall.

[0019] Some exemplary embodiments may further comprise a vertical extension extending upwardly from the upper surface of the base, the vertical extension for connecting the base to the inner component, the vertical extension sized and configured for insertion through the elongate aperture of the lower wall of the corner casting, and the inner component configured for rotation relative to the vertical extension. In some such embodiments, the vertical extension and the inner component may comprise corresponding engagement means for securing them together and preventing rotation of the inner component relative to the vertical extension.

[0020] In some embodiments with the corresponding engagement means, such means may comprise at least one downwardly facing channel in the inner component and at least one upwardly facing engagement member on the vertical extension, the at least one upwardly facing engagement member sized and configured for receipt in the at least one downwardly facing channel. In a first configuration, the vertical extension and the inner component may be aligned such that they can each pass through the elongate aperture with the inner component in the inner cavity, and wherein in a second configuration, the inner component may then be rotated resulting in the vertical extension and the inner component being misaligned such that the inner component engages the upper face of the lower wall and cannot pass back through the elongate aperture, and the corresponding engagement means being engaged thereby securing the protective device to the corner casting.

[0021] In some exemplary embodiments the base and the inner component are separate, further comprising a connector for connecting the base and the inner component and allowing rotation of the inner component relative to the base. In some such embodiments, the connector comprises a bolt, wherein tightening of the bolt after insertion of the inner component into the inner cavity causes the inner component to firmly engage the upper face of the lower wall and causes the base to firmly engage the lower face of the lower wall.

[0022] In some exemplary embodiments, the base comprises at least one peripheral lip sized and configured to overlap at least one edge of the lower wall of the corner casting.

[0023] The base may be co-extensive with the lower wall of the corner casting, narrower than the lower wall of the corner casting, or may extend beyond at least one edge of the lower wall of the corner casting.

[0024] In some embodiments comprising a bolt as the connector, the inner component comprises two spaced-apart channels and the vertical extension comprises two corresponding spaced-apart engagement members, with a passage for the bolt provided therebetween.

[0025] Where a vertical extension is used to connect the base and the inner component, the vertical extension may be integral with the base or it may be separate from the base.

[0026] In some embodiments with the vertical extension, the vertical extension extends upwardly from the upper surface of the base from a point off-centre.

[0027] In some exemplary embodiments, the inner component comprises two laterally extending ends such that the contour of the inner component matches that of the elongate aperture, allowing passage of the inner component therethrough.

[0028] The base is preferably but not necessarily composed of a material selected from the group consisting of ultra-high-molecular-weight polyethylene, polymer-based materials, and composite materials.

[0029] Some exemplary embodiments may include a permanent attachment mechanism tailored to secure the device to ISO corner castings. This attachment mechanism can be implemented through friction-fit designs, high-strength adhesive bonding, bolt(s), or other mechanical fasteners to ensure stability during use, helping to ensure long-lasting durability and stability. This attachment design is intended to prevent detachment or misplacement during transit and may reduce the possibility of the device being lost or damaged. Furthermore, the device's low-friction surface may enhance the efficiency of loading and unloading operations by minimizing resistance, resulting in smoother movement and less strain on handling equipment. This feature may also reduce the likelihood of sudden jerks or stops, which could otherwise lead to equipment strain or movement / damage to loose or affixed contents inside the container.

[0030] One exemplary embodiment of the protective device is designed with a durable system that incorporates sacrificial wear properties allowing the base surface to wear down over time rather than causing damage to the underlying surfaces or the ISO corner castings. The system may be specifically engineered to provide a low coefficient of friction, significantly lower than traditional steel, enabling smoother contact with surfaces such as concrete or metal. This friction-reducing quality may be beneficial for controlled sliding, enhancing both the safety and efficiency of container handling operations. The system may be designed in a way that it can absorb and distribute heavy loads effectively, allowing the protective device to endure the high forces exerted by loaded containers. This makes it suitable for environments with high-frequency handling.

[0031] In another exemplary embodiment, a dual-attachment system may be employed that combines high-strength adhesive with mechanical fasteners such as bolts. The adhesive layer fills any voids between the shoe and the corner casting, helping to ensure a secure bond and enhancing stability. While the adhesive may slightly cushion the device during movement, its primary function is to provide a consistent and durable attachment. The bolts may provide a secure mechanical connection. This combination helps ensure that the shoe remains affixed to the corner casting under various stress conditions, including heavy lifting, high-speed transport, or rapid unloading. Although the device is not intended for intermodal use in ports or rail yards—where ISO castings must remain unobstructed for securing containers to chassis or ships—it is believed to be highly effective for storage and static applications.

[0032] In another exemplary embodiment, the load distribution may be enhanced by increasing the load-bearing coverage area of the corner casting. In this embodiment, the device is designed to cover an area significantly larger than the corner casting. This larger load-bearing surface can be extended on any of the four sides of the corner casting, depending on specific requirements. By reducing the concentration of weight at single points, this embodiment may effectively protect sensitive or high-cost surfaces from cracking, erosion, or wear. The expanded footprint reduces the risk of containers sinking into soft or unstable surfaces, such as asphalt, aggregate, or frost-heaved ground. This embodiment may also help prevent damage from heat-induced sinking and instability during rain or freeze-thaw cycles. The extensive coverage may also enhance the container's stability in high wind regions thereby reducing the risk of ground-level containers overturning during severe weather.

[0033] In some exemplary embodiments, the outer component or base of the device is removable. This modular embodiment of the device features a removable base, allowing for easy replacement when it becomes worn. The removable base may be attached via a snap-lock, threaded, or other suitable attachment mechanism, enabling maintenance teams to replace only the outer section of the device rather than the entire assembly. This approach helps reduce replacement costs, minimizes downtime, and makes it suitable for a wide range of applications, including but not limited to operations with high wear and tear.

[0034] In some exemplary embodiments, the invention incorporates an offset or off-centre device intended to improve container stability by allowing the load-bearing area to be positioned offset from the corner casting. This offset configuration may enhance performance by redistributing weight and reducing the risk of tipping in scenarios such as high-wind regions or uneven terrain.

[0035] The offset design accommodates a variety of applications, offering flexibility in positioning while maintaining stability. These embodiments demonstrate how the offset container shoe addresses specific challenges, such as improving stability under adverse conditions, while remaining adaptable to a broad range of container configurations and uses.

[0036] The protective device can be manufactured to be compatible with standard ISO corner castings, making it suitable for use on a wide range of containers without requiring any modifications to the container itself. It can be adaptable for both new and retrofitted containers, making it a practical solution for rental fleets, asset fleets, and storage containers. By enhancing the stability or portability of shipping containers, it expands their utility for non-intermodal purposes. The installation process is relatively simple and efficient, enabling rapid deployment across large numbers of containers without interrupting the flow of operations.

[0037] The device can provide a durable, abrasion-resistant solution to persistent challenges in container handling. Its design can incorporate materials with high durability and abrasion resistance, a larger load distribution footprint, and a robust attachment system, all of which can contribute to operational efficiency and protection for both infrastructure and containers. While the invention is described using specific embodiments, these examples are intended to be illustrative and not limiting. The scope of the invention includes variations and modifications within the claims set forth herein.

[0038] A detailed description of exemplary embodiments of the present invention is given in the following. It is to be understood, however, that the invention is not to be construed as being limited to these embodiments. The exemplary embodiments are directed to particular applications of the present invention, while it will be clear to those skilled in the art that the present invention has applicability beyond the exemplary embodiments set forth herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In the accompanying drawings, which illustrate exemplary embodiments of the present invention:

[0040] FIG. 1 is an enlarged perspective view of a first exemplary embodiment of the present invention installed on a shipping container.

[0041] FIGS. 2A, 2B, and 2C illustrate perspective views of the first exemplary embodiment of FIG. 1.

[0042] FIG. 3 is an exploded perspective view of the first exemplary embodiment of FIG. 1-2C.

[0043] FIG. 4 is a perspective view of the first exemplary embodiment of FIG. 1-3, assembled.

[0044] FIGS. 5A and 5B illustrate sectional views of the first exemplary embodiment of FIG. 1-4 showing the assembled inner and outer components without and with the corner casting context.

[0045] FIG. 6 illustrates top plan, front elevation, and side elevation views of the base according to the first exemplary embodiment of FIG. 1-5B.

[0046] FIG. 7 illustrates top plan, front elevation, and side elevation views of the inner component according to the exemplary embodiment of FIG. 1-5B.

[0047] FIGS. 8A, 8B, and 8C show perspective views of the first exemplary embodiment of FIG. 1-7 installed on a shipping container.

[0048] FIG. 9 illustrates a front perspective view of a second exemplary embodiment of the present invention, showing an enlarged load-bearing area.

[0049] FIG. 10 illustrates a perspective view of the exemplary embodiment of FIG. 9 installed on a shipping container, with the enlarged load-bearing area and its alignment with the corner casting.

[0050] FIG. 11 is a perspective view of a third exemplary embodiment of the present invention, the components modular and assembled including a removable base.

[0051] FIG. 12 is an exploded view of the exemplary embodiment of FIG. 11, showing the removable base detached from the vertical extension.

[0052] FIG. 13 is a perspective view of a shipping container with the exemplary embodiment of FIG. 11-12 installed.

[0053] FIG. 14 is an enlarged perspective view of a fourth exemplary embodiment of the present invention, including an offset shoe design, installed on a corner casting.

[0054] FIG. 15 is a perspective view of the uninstalled exemplary embodiment of FIG. 14.

[0055] FIG. 16 is a perspective view of a shipping container with the embodiment of FIG. 15 installed thereon.

[0056] FIG. 17A-17G illustrates the installation stages for the first embodiment of FIG. 1-8C.

[0057] Exemplary embodiments will now be described with reference to the accompanying drawings.DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0058] Throughout the following description, specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. The following description of examples of the invention is not intended to be exhaustive or to limit the invention to the precise form of any exemplary embodiment. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense. The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements.

[0059] Turning now to the drawings, exemplary embodiments of the present invention are illustrated. FIG. 1 provides an enlarged view of a corner casting 16 of a shipping container 18. A protective device or container shoe 12 is secured to the corner casting, covering its bottom surface. The container shoe 12 extends beyond the dimensions of the corner casting 16 to enhance load distribution and provide additional protection. Constructed from abrasion-resistant materials, the container shoe 12 reduces wear during handling and incorporates a low-friction interface to minimize impact pressure during unloading. By preventing direct contact between the corner casting 16 and the ground, the container shoe 12 improves the durability of the shipping container 18 and protects the surfaces it interacts with.

[0060] FIGS. 2A, 2B, and 2C illustrate various perspective views of the container shoe 12 in relation to the corner casting 16.

[0061] FIG. 2A shows the external configuration, showcasing the expanded footprint of the base 14 (with a lip 40 extending beyond the edge of the casting 16) and its role in distributing weight and enhancing stability.

[0062] FIG. 2B shows the internal configuration, illustrating how the inner component 26 interacts with the corner casting 16 to establish a secure connection, with the base 14 providing additional support. It is clear from FIG. 2B that the there are front and back lips 40, covering the front and rear bottom edges 42, 44 of the corner casting 16. Also, a bolt 46 can be seen in FIG. 2B, which is used to connect the base 14, the vertical extension 28, and the inner component 26, as described below.

[0063] FIG. 2C focuses on the interaction between the inner component 26 and the base 14, with the vertical extension 28 enhancing the secure interface and contributing to the overall functionality and resilience of the container shoe 12.

[0064] FIG. 2A-2C also illustrate an access aperture 62, which allows the user to access the inner cavity of the corner casting 16 to rotate the inner component 26 once the inner component 26 has passed through the elongate aperture 62 (which aperture 62 can be seen in FIG. 5B).

[0065] FIG. 3 depicts an exploded view of the container shoe 12 and its primary components. The inner component 26 is positioned inside the corner casting 16 to establish a secure connection. The base 14 remains outside the corner casting 16, providing external support and distributing weight. The vertical extension 28, which is integral with the base 14 in this embodiment, extends into the corner casting 16 and interfaces with the inner component 26. This configuration enhances the connection between the components, contributing to improved stability and weight distribution while maintaining a secure and functional interface during container handling operations.

[0066] FIG. 3 also illustrates the means by which the inner component 26 engages with the vertical extension 28 to secure the device 12 to the corner casting 16. The inner component 26 comprises two downwardly facing channels 48, which are sized and configured to receive corresponding upwardly facing engagement members 50 on the vertical extension 28. When the inner component 26 is rotated to the position shown relative to the vertical extension 28, the engagement members 50 can be inserted into the channels 48, thereby locking the inner component 26 and the vertical extension 28 together and preventing further rotation.

[0067] FIG. 4 illustrates an assembled view of the container shoe 12, showing how its components are configured in relation to the corner casting 16. The container shoe 12 is first assembled, with the inner component 26 positioned inside the corner casting 16 and securely interfaced with the vertical extension 28 of the base 14 using the corresponding engagement members 50 and the channels 48. This arrangement allows the shoe 12 to be separated and reassembled during installation by placing the inner component 22 inside the corner casting 16. This arrangement ensures a secure attachment to the corner casting, enhancing stability and protecting the unloading surface while accommodating a range of operational requirements.

[0068] FIGS. 5A and 5B illustrate a cross-sectional view of the container shoe 12 as shown in FIG. 4 connected with the corner casting 16 on the container 18. As can be seen, the engagement members 50 of the vertical extension 28 interface with the channels 48 in the inner component 26, with the bolt 46 used to tighten the components together such that the base 14 firmly engages the lower face 52 of the lower wall 54 of the corner casting 16 while the inner component 26 firmly engages the upper face 56 of the lower wall 54 of the corner casting 16. The inner component 26 is designed to engage securely with the corner casting 16, ensuring proper alignment and stability. The base 14 extends outward to cover the corner casting 16, improving weight distribution and protecting the underlying surface. The bolt 46 head is recessed within the material and runs through the vertical extension 28 and the inner component 26, ensuring that the base 14 fully wears out before the bolt 46 can come into contact with or damage the surface beneath. Also, it can be seen in FIGS. 5A and 5B that the vertical extension 28 is provided with lips 58, which engage the lower wall 54 when the vertical extension 28 passes through the elongate aperture 60.

[0069] FIG. 6 provides top plan, front elevation, and side elevation views of the base 14 of the container shoe 12. The design incorporates features that enhance load distribution and reduce surface pressure, ensuring optimal performance during container handling. It supports secure attachment through multiple mechanisms, such as a friction-fit interface, and facilitates the use of an adhesive to strengthen the connection. These design elements collectively contribute to improved functionality and durability during use.

[0070] FIG. 7 illustrates top plan, front elevation, and side elevation views of the inner component 26 of the container shoe 12. This component is designed to be positioned within the corner casting 16, facilitating a secure and stable connection. Its configuration ensures reliable functionality and structural integrity during container handling operations.

[0071] FIGS. 8A, 8B, and 8C illustrate perspective views of a container 18 equipped with container shoes 12 installed on the corner castings 16. These views show the container 18 from different positions, highlighting how the container shoes 12 are securely attached to the corner castings 16. The design ensures stable placement on the ground, effectively distributing weight and maintaining level positioning. Additionally, the container shoes facilitate smooth movement across surfaces, minimizing the risk of scratches or damage to unloading areas.

[0072] FIG. 9 illustrates an assembled perspective view of an alternative embodiment of the present invention, a container shoe 10, with an enlarged base 20 providing an increased load-bearing area. This design efficiently distributes weight over a larger surface, reducing localized pressure and enhancing stability, making it ideal for applications requiring durable and reliable support.

[0073] FIG. 10 illustrates a container 18 equipped with the container shoe 20 of FIG. 9 featuring the enlarged load-bearing area. The container shoe 20 is designed to align with the corner casting 16. This configuration enhances weight distribution, minimizes surface pressure, and improves the container's stability in high-wind regions, reducing the risk of ground-level containers overturning during severe weather.

[0074] FIG. 11-13 illustrate a third exemplary embodiment of a shoe 32 according to the present invention. As can be seen in FIG. 11, a vertical extension 22 is separate from a base 24 (unlike the unitary construction illustrated in FIG. 1, for example). These views highlight the modular nature of the embodiment, designed for increased performance, including wear resistance and ease of detachment. The base 24 is securely attached to the vertical extension 22 and an inner component 30 of the shoe 32. The base 24 is shown as flush with the vertical extension 22, emphasizing its alignment and design for durability and ease of replacement.

[0075] FIG. 12 presents an exploded perspective view of the protective device 32, focusing on the modular design featuring the removable base 24. This view clearly shows the individual parts of the device 32, including:

[0076] The removable base 24, designed for enhanced performance, including wear resistance and ease of detachment.

[0077] The vertical extension 22 and the inner component 30, which may employ snap-lock, threaded, or other suitable interfaces to enable secure and efficient assembly. FIG. 12 illustrates the simplicity and practicality of replacing only the outer component when it becomes worn.

[0078] FIG. 13 depicts the device 32 installed on a shipping container 18, showing the removable base 24 in its operational configuration. This perspective emphasizes the practical application of the design, demonstrating how the shoe 32 interfaces with the corner casting 16 and the proper alignment. This figure underscores the utility of the removable base 24 design in real-world applications, illustrating its versatility and ease of use across a broad range of operational needs.

[0079] FIG. 14-16 illustrate a further exemplary embodiment of the present invention, in which the base 34 is provided with an offset interface for the vertical extension 36. FIG. 14 provides an enlarged perspective view of a shoe 38 installed on the container 18, showcasing the offset design. The illustration highlights how the container shoe 38 integrates with the container's corner casting 16 while being offset to redistribute weight and enhance stability. The container shoe 38 is positioned with an intentional offset from the corner casting 16, extending the load-bearing area beyond the casting's boundaries. This design minimizes surface pressure and provides greater stability, particularly in high-wind conditions. The enlarged load-bearing surface is visible, demonstrating how it reduces pressure on the supporting ground and prevents tipping risks.

[0080] FIG. 15 provides an assembled perspective view of the device 38, showcasing its offset design. This view provides a comprehensive view of the system in its final assembled form, demonstrating the functionality and alignment of the components.

[0081] FIG. 16 presents a perspective view of the shoes 38 installed on a shipping container 18, showcasing the offset design. The illustration demonstrates the practical application of the system, showing how it is mounted and integrated with the corner casting 16. Specific attention is given to the offset configuration, which ensures proper alignment and improved stability in high-wind regions.

[0082] Turning now to FIG. 17A-17G, the stages of installing the device 12 (of the first embodiment of FIG. 1-8C) are illustrated. FIG. 17A illustrates the step of positioning the inner component 26 for connection to the vertical extension 28 of the base 14. Note that the long axis of the inner component 26 is aligned with the long axis of the vertical extension 28 (which allows them to be inserted together through the elongate aperture 60 in the lower wall 54 of the corner casting 16), such that the channels 48 are misaligned with the engagement members 50. The base 14 comprises forward and rearward lips 40 for engagement with the front and rear bottom edges 42, 44 of the corner casting 16 of the shipping container 18.

[0083] FIG. 17B illustrates the step of connecting the inner component 26 to the vertical extension 28 of the base 14, using the bolt 46. The bolt 46 is threaded upwards through a hole 64 in the base 14 and the vertical extension 28, and then through a corresponding hole 66 (shown in FIG. 17A) in the inner component 26. The bolt 46 should be threaded into the inner component 26, but only to the point that the inner component 26 is still rotatable relative to the vertical extension 28. FIG. 17C shows the stage where the base 14, the vertical extension 28, and the inner component 26 are connected together by the bolt 46, but where the inner component 26 is still rotatable relative to the vertical extension 28 (with the channels 48 misaligned with the engagement members 50).

[0084] FIG. 17D shows the corner casting 16 on the shipping container 18, with the device or shoe 12 positioned for insertion therein. The corner casting 16 is provided with access apertures 62 allowing the user to both view the inner component 26 upon insertion into the inner cavity of the corner casting 16 and rotate the inner component 26, as described below.

[0085] FIG. 17E illustrates the step where the inner component 26 and the vertical extension 28 have passed through the elongate aperture 60 in the lower wall 54 of the corner casting 16. The base 14 is engaged with the lower face 52 of the lower wall 54, with the lips 40 engaging the front and rear bottom edges 42, 44 of the corner casting 16. The inner component 16 is visible and accessible through the access apertures 62 in the corner casting 16. At this stage the long axis of the inner component 26 is still aligned with the long axis of the vertical extension 28, with the channels 48 and the engagement members 50 still misaligned, and the inner component 26 is still rotatable relative to the vertical extension 28.

[0086] FIG. 17F illustrates the step wherein the inner component 26 is accessed through the access apertures 62 in the corner casting 16 and rotated relative to the vertical extension 28. Upon rotation out of alignment with the long axis of the vertical extension 28 (for example 90 degrees), the lateral ends of the inner component 26 are now above the upper face 56 of the lower wall 54 such that the inner component 26 cannot be pulled back through the elongate aperture 60. At this stage the bolt 46 has not been fully tightened, and the engagement members 50 are not mated with the channels 48, but the shoe 12 cannot be disengaged from the corner casting 16 as the inner component 26 has been rotated. The rotation places the engagement members 50 into alignment with the channels 48, but they are not yet engaged.

[0087] FIG. 17G illustrates the final tightening step of the installation of the device 12 in the corner casting 16. In this step, the bolt 46 is fully tightened, which has the effect of moving the base 14 upwardly against the lower face 52 of the lower wall 54 of the casting corner 16, while at the same time moving the inner component 26 downwardly against the upper face 56 of the lower wall 54. By moving the base 14 and the inner component 26 towards each other through tightening of the bolt 46, the now-aligned engagement members 50 of the vertical extension 28 are forced into the channels 48 of the inner component 26, with the lips 58 of the engagement members 50 abutting the upper face 56 of the lower wall 54. The shoe 12 is now firmly installed on the corner casting 16.

[0088] The foregoing is considered as illustrative only of the principles of the present invention. The scope of the claims should not be limited by the exemplary embodiments set forth in the foregoing, but should be given the broadest interpretation consistent with the specification as a whole.

Claims

1. A protective device for installation on a corner casting of a shipping container, the corner casting comprising walls defining an inner cavity, the walls comprising a lower wall, the lower wall having an upper face and a lower face and including an elongate aperture therethrough, the protective device comprising:a base having upper and lower surfaces, the upper surface configured for engagement with the lower face of the lower wall of the corner casting, and the lower surface configured for engagement with a ground surface to provide a barrier between the corner casting and the ground surface;an inner component sized and configured for insertion through the elongate aperture; andconnection means for connecting the base to the lower face of the lower wall of the corner casting.

2. The protective device of claim 1 wherein the connection means comprise the inner component being rotatable between first and second configurations:wherein in the first configuration the inner component is rotated into an aligned orientation aligned with the elongate aperture to allow insertion of the inner component therethrough into the inner cavity; andwherein in the second configuration the inner component is rotated into a misaligned orientation disallowing passage of the inner component out of the inner cavity through the elongate aperture, such that the inner component engages the upper face of the lower wall and the base is retained against the lower face of the lower wall to provide the barrier.

3. The protective device of claim 2 wherein the corner casting further comprises a side wall comprising an access aperture, the access aperture allowing access to the inner component in the inner cavity for rotation of the inner component between the aligned and misaligned orientations.

4. The protective device of claim 2 wherein the inner component comprises at least one laterally extending end and is shaped so as to pass freely through the elongate aperture when in the aligned orientation, wherein in the misaligned orientation the at least one laterally extending end engages the upper face of the lower wall to prevent passage of the inner component back through the elongate aperture.

5. The protective device of claim 2 wherein the inner component is rotatable relative to the base, allowing rotation of the inner component within the inner cavity while the base is aligned with the lower face of the lower wall.

6. The protective device of claim 1 further comprising:a vertical extension extending upwardly from the upper surface of the base, the vertical extension for connecting the base to the inner component, the vertical extension sized and configured for insertion through the elongate aperture of the lower wall of the corner casting; andthe inner component configured for rotation relative to the vertical extension.

7. The protective device of claim 6, wherein the vertical extension and the inner component comprise corresponding engagement means for securing them together and preventing rotation of the inner component relative to the vertical extension.

8. The protective device of claim 7, wherein the corresponding engagement means comprise at least one downwardly facing channel in the inner component and at least one upwardly facing engagement member on the vertical extension, the at least one upwardly facing engagement member sized and configured for receipt in the at least one downwardly facing channel.

9. The protective device of claim 7, wherein in a first configuration, the vertical extension and the inner component are aligned such that they can each pass through the elongate aperture with the inner component in the inner cavity, and wherein in a second configuration, the inner component is rotated resulting in the vertical extension and the inner component being misaligned such that the inner component engages the upper face of the lower wall and cannot pass back through the elongate aperture, and the corresponding engagement means being engaged thereby securing the protective device to the corner casting.

10. The protective device of claim 1 wherein the base and the inner component are separate, further comprising a connector for connecting the base and the inner component and allowing rotation of the inner component relative to the base.

11. The protective device of claim 10 wherein the connector comprises a bolt, wherein tightening of the bolt after insertion of the inner component into the inner cavity causes the inner component to firmly engage the upper face of the lower wall and causes the base to firmly engage the lower face of the lower wall.

12. The protective device of claim 1 wherein the base comprises at least one peripheral lip sized and configured to overlap at least one edge of the lower wall of the corner casting.

13. The protective device of claim 1 wherein the base is co-extensive with the lower wall of the corner casting.

14. The protective device of claim 1 wherein the base is narrower than the lower wall of the corner casting.

15. The protective device of claim 1 wherein the base extends beyond at least one edge of the lower wall of the corner casting.

16. The protective device of claim 11, wherein the inner component comprises two spaced-apart channels and the vertical extension comprises two corresponding spaced-apart engagement members, with a passage for the bolt provided therebetween.

17. The protective device of claim 6 wherein the vertical extension is integral with the base.

18. The protective device of claim 6 wherein the vertical extension is separate from the base.

19. The protective device of claim 6 wherein the vertical extension extends upwardly from the upper surface of the base from a point off-centre.

20. The protective device of claim 4 wherein the inner component comprises two laterally extending ends such that the contour of the inner component matches that of the elongate aperture, allowing passage of the inner component therethrough.

21. The protective device of claim 1 wherein the base is composed of a material selected from the group consisting of ultra-high-molecular-weight polyethylene, polymer-based materials, and composite materials.

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