Joint arrangement of crane

Abstract

A joint arrangement between a frame (1) and a bogie corner (2) of a crane configured to run on fixed rails or floating rails, comprising a pin (3) protruding from a sill beam (10) of the frame (1) and connected to an aperture of the bogie corner (2) and configured to allow rotational movement in relation to the bogie corner (2), and a sliding element (30).

Description

[0001] Joint arrangement of crane

[0002] Background

[0003] The invention relates to a joint arrangement, and especially a joint arrangement in a crane between the frame and bogie corner.

[0004] For example, a typical automated stacking crane ( SCj has four bogie corners, which is a component of the crane’s undercarriage. Cranes that utilise bogies are often designed for heavy lifting and transportation tasks, such as those found in ports, shipyards, construction sites and industrial facilities.

[0005] The bogie is a subassembly that supports and connects the crane's wheels or tracks to its main structure, such as the frame. The bogie comprises axles, wheels, suspension systems, and sometimes motors or drive systems. Bogies play a crucial role in the mobility and stability of cranes, especially those designed for traversing rough terrain or operating on uneven surfaces. They distribute the crane's weight evenly across multiple wheels or tracks, enhancing traction and maneuverability. They ensure the safe and efficient operation of cranes in various industrial and construction settings.

[0006] The frame of the crane is secured to the bogie via a sill beam which is a horizontal beam and forms part of the crane’s frame. The sill beam serves as a primary support structure for the crane's gantry or trolley. Its robust construction and strategic placement help ensure that the crane can handle heavy loads safely and efficiently. It typically spans the width of the crane and provides a stable foundation for mounting various components, including the hoisting mechanism, trolley, etc. The sill beam provides attachment points for the bogies. The bogies then travel along rails or tracks parallel the sill beam, allowing the crane to move horizontally along the designated path.

[0007] The sill beam is designed with specific mounting points or brackets that are positioned to align with corresponding attachment points on the bogie. Once the bogie is positioned beneath the sill beam, fastening mechanisms such as bolts, pins, or welding are used to secure the connection between the two components. Bolts or pins may be inserted through pre-drilled holes in the mounting brackets of the sill beam and corresponding holes or brackets on the bogie.

[0008] The challenge of this alignment is that it is time consuming and expertise knowledge is needed. Engineering tolerances and alignment features must be carefully considered during the design and fabrication of both the sill beam and bogie to ensure proper fit and alignment when they are connected. In addition, even if the bogie and the sill beam are correctly aligned, there is no guarantee that there is no wheel or / and guide roller wear. The yard comprising rails are not typically in perfect conditions, and there are lots of deviation in rail straightness. The ground may also sink over the time which causes unevenness.

[0009] Brief disclosure

[0010] An object of the invention is thus to provide an arrangement that solves or at least alleviates the aforementioned problems. The invention is based on a joint arrangement that makes the crane adaptable to rail conditions.

[0011] Another object of the invention is to provide an arrangement which can be easily retrofitted to the existing cranes.

[0012] Brief description of the drawings

[0013] The invention will now be described in more detail in connection with preferred embodiments and with reference to the accompanying drawings, in which:

[0014] Figure 1 illustrates an isometric view of a joint arrangement between a bogie corner and a sill beam according to an embodiment;

[0015] Figure 2 illustrates a closer side view of the joint arrangement of Figure 1;

[0016] Figure 3 illustrates a front view of the joint arrangement of Figure 1;

[0017] Figure 4 illustrates a cross-sectional view of the joint arrangement of Figure 1;

[0018] Figure 5 illustrates an embodiment of the joint arrangement with a counter plate and a locking plate;

[0019] Figure 6 illustrates an isometric view of the joint arrangement with a protective cover;

[0020] Figure 7 illustrates an isometric view of a joint arrangement between a bogie corner and a sill beam according to another embodiment;

[0021] Figure 8 illustrates a side view of the joint arrangement of Figure 7;

[0022] Figure 9 illustrates a front view of the joint arrangement of Figure 7.

[0023] Detailed description of embodiments

[0024] The present invention pertains to a joint arrangement in a crane between the frame 1 and the bogie corner 2. The crane in this context may refer to any type of crane which is configured to run or travel on fixed rails or floating rails, such as an automated stacking crane (ASC), rail mounted gantry (RMG) crane, ship- to-shore (STS) crane, or shipyard crane for example. Fixed rails are anchored, for example by welding, to a structure of the building or support columns, and provide a stable and rigid path for the crane to move along. Fixed rails provide a predetermined path for the crane and does not usually need to be altered. The floating rails are not permanently fixed to the structure but are installed on movable supports or platforms, for example by using clamps. They can be adjusted to accommodate changes in the area’s layout so they are more versatile and allow customization of the crane’s path.

[0025] There are typically four bogie corners 2 supporting one crane having two sill beams 10. One sill beam 10 is thus supported by two bogie corners 2 on its opposite ends. Each bogie corner 2 may comprise one or two bogies 21. Each bogie 21 may comprise two wheels 22. In case of two bogies 22 in one bogie corner 21, the two bogies 21 are aligned on a same longitudinal axis and a bogie balancer 23 is arranged and balanced on top of the two bogies 21.

[0026] Figures 1-4 illustrate a joint arrangement between a bogie corner 2 and a sill beam 10 according to an embodiment. The sill beam 10 may have a box-type beam with side walls 9 and a bottom wall 8. The bogie corner 2 and the frame 1 are connected to each other via a pin 3, which can be vertically positioned, so that the bogie corner 2 can be kept in its position when crane is jacked up. The sill beam 10 may comprise a bottom plate 11, also may be known as sill beam flange, arranged at a bottom of opposite ends of the sill beam 10, wherein the bottom plate 11 may have a width which is wider than the width of the bottom wall 8 to form at least one flange. The bottom plate 11 may be welded to the bottom wall 8 of the boxtype beam. The pin 3 may be welded to the centre of the bottom plate 11 so that the pin 3 protrudes downward from the sill beam 10. The pin 3 is the rotation axel but also takes forces at the rail direction, such as acceleration, braking and crane to crane collision, etc. Around the pin 3 there may be sliding bushing and pin locking plates.

[0027] Correspondingly, the bogie corner 2 may comprise a top plate 24, also may be known as bogie corner flange, having an aperture for receiving the pin 3. The top plate 24 may have a same width or smaller than the bottom plate 11 of the frame 1.

[0028] The pin 3 may be rigidly secured to the top plate 24 using fasteners, for example, so that the pin 3, having a circular cross-section, is configured to allow rotational movement in relation to the top plate 24 of the bogie corner 2. The pin 3 also has enough strength to take forces to withstand crane-to-crane or crane-to- yard collision. Due to keeping the balances, the aperture for the pin 3 is typically located longitudinally in the middle section of the bogie corner 2.

[0029] The joint arrangement according to the invention comprises a sliding element 30 arranged between the sill beam 10 and the bogie corner 2. The sliding element 30 in this context refers to a material which has low friction coefficient, such as less than 0,32, or less than 0,22 or 0,05 to 0,2, and preferably good wear resistance and mechanical properties for surface pressure, for example. The sliding element 30 may be made of maintenance free material, such as dry lubricants or solid lubricants, for example. Despite being in the solid phase, they are able to reduce friction between two surfaces sliding against each other without the need for a liquid oil medium. In some embodiments, the sliding element’s 30 material may be engineering plastic, such as polyoxymethylene thermoplastic, such as acetal copolymer (POM-Cj. In some embodiments, the sliding element’s 30 material may be metallic, such as bronze sheet with polytetrafluoroethylene [PTFE] coating, or stainless steel with zinc coating, for example.

[0030] The sliding element 30 may be connected to the sill beam 10 and may be in a form of a sheet with even thickness. It can be connected to the sill beam 10 or the bottom plate 11 of the sill beam 10 by fasteners 31, such as bolts, or welded directly between the sliding element 30 and the sill beam 10, and / or between the sliding element 30 and the bottom plate 11. In the accompanying Figures, the top plate 24 of the bogie corner 2 has a smaller length, along the longitudinal axis of the sill beam 10, than the bottom plate 11 of the sill beam 10, and also the length of the sliding element 30, so the top plate 24 does not obscure the fasteners 31 of the sliding element 30. However, the width, perpendicular to the longitudinal axis of the sill beam 10, of the top plate 24 and the bottom plate 11 may be equal or almost equal.

[0031] The pin 3 is arranged to receive the forces when the crane is travelling and / or the container is moved. The pin 3 has a circular cross-section with a diameter which may be equal or larger than the thickness of thinner plate of either one, the bottom plate 11 or the top plate 24. The pin 3 has a circular cross-section with a diameter which may be equal or larger than the combined thickness of the bottom plate 11 and the top plate 24. This allows the sliding element 30 to withhold the stress both during the travel operation and movement of the container in the direction of the main girder, which proves more efficiency in the operation when the operator does not need to wait until the crane is stopped to start moving the container.

[0032] The pin 3 may comprise a pin neck 36 and a pin flange 37 at the end of the pin 3. The pin neck 36 has a smaller diameter than the pin flange 37. The pin flange 37 may have an equal or larger diameter than the pin 3 section above the pin neck 36. Larger diameter of the pin flange 37 can provide the needed support against a tilting load, and if the bogie is lifted from below. Rotation of the pin 3 can be limited by using a non-rotationally symmetrical pin flange 36, with cuts and stoppers for example, or the rotation counter surfaces can be made sufficiently far from the axis of rotation to ensure that shearing of the pin and the cuts and stopper is prevented.

[0033] In the accompanying Figures 1-4, the sliding element 30 is illustrated as a cuboid shape so that it has two large opposite rectangular faces functioning as contact areas, wherein the first rectangular face is facing towards the bottom plate 11 and the second rectangular face is facing towards the top plate 24. The second rectangular face may also act as a sliding surface. The sliding surface in this context refers to the surface of the sliding element 30 which is enabled to slide in relation to the bogie corner 2 and in this embodiment also contacts the top plate 24 of the bogie corner 2. However, in some embodiments, the contact area may have a different shape, for example it may have same or narrower shape as the bottom plate 11, or it may have an outline of a square with a hole larger than the aperture.

[0034] The rectangular face may have longitudinal edges, and transverse edges, which are shorter than the longitudinal edges. The longitudinal edges may be parallel to the longitudinal axis of the sill beam 10, whereas the transverse edges are perpendicular to the longitudinal axis of the sill beam 10. The transverse edge may be more than 5% and less than 50% of the width of the bottom plate 11. In some cases, the transverse edge may more than 10% and less than 40% of the width of the bottom plate 11. In some cases, the transverse edge may more than 10% and less than 20% of the width of the bottom plate 11 to obtain a sufficient contact area.

[0035] In the embodiment illustrated in Figures 1-4, the joint arrangement has two sliding elements 30 arranged on opposite sides of the pin 3 and at an equal distance away from the pin 3 so that two sliding elements are longitudinally parallel to each other and also parallel to the longitudinal axis of the sill beam 10. However, the number of the sliding elements 30 may vary depending on the design of the sill beam 10 and the bogie corner 2. For instance, there may be two sliding elements 30 on one side of the pin 3 and two sliding elements 30 on the opposite side of the pin 3. The contact area preferably covers the effective contact area to which the most surface pressure is directed to. In the case of ASC, this surface pressure is caused by the side wall 9 of the sill beam 10 and support column 25 of the bogie corner 2, which are located directly below the top plate 24.

[0036] The sliding element 30 has a thickness, which may be less than 5 mm, especially less than 3 mm or less than 2 mm. The thickness may form a gap 32 between the sill beam 10 and the bogie corner 2, wherein the gap 32 has a height which is same as the thickness of the sliding element 30. The gap 32 prevents the sill beam 10 and the bogie corner 2 from contacting each other so that the only contact area is via the sliding element 30.

[0037] The joint arrangement may further comprise a counter plate 34, as illustrated in Figure 5, arranged between the sliding element 30 and the bogie corner 2. In this embodiment, the sliding surface refers to the surface of the sliding element 30 which contacts the counter plate 34. The counter plate 34 may be rigidly attached to the top plate 24 of the bogie corner 2. The counter plate 34 ensures that the sliding surface is good, and the top plate 24 can have proper surface treatment. The counter plate 34 may also prevent corrosion. The counter plate 34 may be manufactured from metal, such as stainless steel. Counter plate 34 can be bolted and / or welded to the edge or perimeter of the top plate 24. A least one and especially all four of the edges of the counter plate 34 may be bent approximately 90 degrees so that the bolts and / or welding are secured to the top plate 24 through the bent edges. The counter plate 34 may cover the whole top surface of the top plate 24 and has a similar aperture for the pin 3. The top surface of the top plate 24 refers to the surface facing towards the sliding element 30.

[0038] The joint arrangement may further comprise a locking plate 35, as illustrated in Figure 5, arranged between the sliding element 30 and the sill beam 10. The locking plate 35 may be attached to the bottom plate 11 of the sill beam 10 and is configured to help keeping the sliding plate 30 in its position. The locking plate 35 may also prevent corrosion. The locking plate 35 may be manufactured from metal, such as stainless steel. The locking plate 35 may be bolted and / or welded to the bottom surface of the bottom plate 11 so that the sliding element 30 is attached to the bottom plate 11 through the locking plate 35. The locking plate 35 may cover the whole bottom surface of the bottom plate 11 and has a similar aperture for the pin 3. The bottom surface of the bottom plate 11 refers to the surface facing towards the sliding element 30.

[0039] Figure 6 illustrates a joint arrangement according to an embodiment with a protective cover 33. The protective cover 33 is arranged to cover the sliding element 30 and possibly also the bottom plate 11 and the top plate 24. The protective cover 33 is configured to protect the sliding element 30 from UV light, rain and debris so that it remains clean and without affecting to the sliding element’s 30 properties. UV light and dirt may damage certain molecules which causes material degradation. The protective cover 33 may be removable so that the maintenance personnel may inspect the sliding element 30 for maintenance purposes. The protective cover 33 may be bolted or screwed to near the edge of the top surface of the bottom plate 11. The top surface of the bottom plate 11 refers to the surface facing away from the sliding element 30. The protective cover maybe manufactured from bendable sheet or sheets, for instance bent 90 degrees, to form at least partially continuous side which covers the sliding element 30. It may also be welded from several sheets to form the at least partially continuous side.

[0040] The joint arrangement may further comprise a claw arrangement 40 connected to the side wall 9 of the sill beam 10 and configured to prevent rotation of the sill beam 10 about the pin 3 over a predetermined limit. The claw arrangement 40 may be located at the longitudinal vertical side wall 9 of the sill beam 10 and on both side walls 9 so that each end of the sill beam 10 comprises two claw arrangements 40.

[0041] The claw arrangement 40 may comprise a shaft plate 41 and a claw 42. The claw 42 in this context refers to a structure having a J-shaped cross section wherein a tip 43 of the claw 42 extends under the top plate 24 of the bogie corner 2 without touching the top plate 24. There may be a small gap between the tip 43 and the bottom surface of the top plate 24, for example less than 3 mm, and especially less than 1 mm. The bottom surface of the top plate 24 refers to the surface facing away from the sliding element 30. This configuration allows the claw 42 to grip under the top plate 24 in case the sill beam 10 tilts over a predetermined limit, for example due to an accident or earthquake. The claw 42 may be manufactured from a laser cut metal sheet, for example.

[0042] The shaft plate 41 may be rigidly connected to the claw 42 by welding, for example. In the accompanying Figures, the shaft plate 41 is illustrated as a plate with uniform thickness, wherein the claw 42 is horizontally connected to a vertical surface of the shaft plate 41. The claw 42 may be arranged perpendicular to the shaft plate 41. However, the shaft plate 41 may have other shapes than the plate.

[0043] The claw arrangement 40 may further comprise a fin 44 protruding from the side wall 9 of the sill beam 10. The sill beam 10 may be rigidly connected to the fin 44 by welding, for example. The fin 44 may be attached to a counterpart 45, perpendicular to the fin 44. The counterpart 45 and the shaft plate 41 may be parallel to each other and attached to each other by fasteners 46, such as bolts, for example. In the accompanying Figures, six bolts were used, three on each side of the claw 42. However, a different number of the bolts may be used.

[0044] The counterpart 45 may be located completely above the bottom plate 11 of the sill beam 10, while the shaft plate 41 may extend past the bottom plate 11 of the sill beam 10 and the top plate 24 of the bogie corner 2. However, the shaft plate 41 may not touch the top plate 24 in a normal setup. Instead, the shaft plate 41 may prevent the rotation about the pin 3 over the predetermined limit. The shaft plate 41 may comprise at least two prongs 47 at the lower end of the shaft plate 41, wherein a part of the claw 42 may be arranged between the prongs 47 to further improve the rigidity of the claw arrangement 40.

[0045] The claw 42 has at least two functions: 1) to maintain the vertical load holding during accident, strong wind, or earthquake, for example; and 2) to prevent the 360 degree or less rotation at the sliding element 30. The vertical load in the joint arrangement can be distributed between the pin 3 and the claw arrangement’s fin 44, counterpart 45, and shaft plate 41.

[0046] Figure 7 illustrates an isometric view of a joint arrangement between a bogie corner and a sill beam according to another embodiment. Figure 8 illustrates a side view and Figure 9 illustrates a front view of the joint arrangement of Figure 7. The embodiment of Figures 7-9 is very similar to the one explained in connection with Figures 1-6. Therefore, the embodiment of Figures 7-9 is in the following mainly explained by pointing out differences.

[0047] In this embodiment, the bottom plate 11 and the top plate 24 may be further extended in the direction away from the sill beam 10 so that both the bottom plate 11 and the top plate 24 comprises a projection and a through hole for accommodating an additional pin 12. The additional pin 12 can be T-shaped with a wider section on top to connecting the additional pin 12 to the bottom plate 11 and / or preventing the additional pin 12 passing though the through holes. The through hole of the bottom plate 11 can be identical with the through hole of the top plate 24, or they can be different. The through hole can be circular or oval or arch shaped. The arch shaped form is surrounding the pin 3 with a radius, thus allowing rotation around the pin 3. The additional pin 12 can be loosely fit within either the through hole of the bottom plate 11 or the through hole of the top plate 24, or both. The additional pin 12 is preferably attached to either the bottom plate 11 or the top plate 24, and the respective top plate 24 or the bottom plate 11 is loosely fitted around the additional pin 12. The loosely fitted additional pin 12 can allow the slight rotation of the bogie in relation to the sill beam 10, although the rotation is limited between the extreme positions of the through hole.

[0048] Large vertical load changes can occur during the crane’s travelling movement, and the joint arrangement prevents the joint from opening even when the crane moves longitudinally parallel to the ground, e.g. on rails, and at the same time the crane can move the container in the direction of the main girder supported by the trolley, as can be the case with the ASC.

[0049] The solution is useful when driving on a straight rail in the container yard, i.e. the rail installation has been initially straight, to which straightness can be changed by time and the use of the crane. The solution is also useful for curved rails. When ports near large cities are expanded due to urbanization and increased port capacity, curved rail sections may have to be built on the site to connect different parts of the port.

[0050] The present invention allows the crane to have a sliding connection between the sill beam 10 and the bogie corner 2, which stabilises the forces caused by bad rail conditions and allows the crane to become more adaptable to different rail conditions. It also allows driving in the curved rails, which is an important feature especially for RMG and STS cranes. The present invention reduces the maintenance time and cost as components will last longer and there will be less downtime. For example, roller replacement happens very often, which requires service, and it is one of the many situations the present invention will improve.

[0051] Another important aspect of the present invention is to possibility to retrofit the existing ASC with the joint arrangement to improve the situation of the older ASCs which are already in use. Since the joint arrangement is to be connected to the sill beam 10, it is quite a straightforward way to lift the sill beam 10, move the bogie corner 2 from the way, and implement the joint arrangement. No additional structural changes to the crane is needed.

Claims

Claims1. A joint arrangement between a frame and a bogie corner of a crane configured to run on fixed rails or floating rails, comprising a pin protruding from a sill beam of the frame and connected to an aperture of the bogie corner and configured to allow rotational movement in relation to the bogie corner, and a sliding element.

2. The joint arrangement according to claim 1, wherein the sliding element form a gap between the sill beam and the bogie corner, the gap has a height which is same as a thickness of the sliding element.

3. The joint arrangement according to claim 1 or 2, wherein the sliding element is connected to the sill beam, such as by fasteners or welded.

4. The joint arrangement according to any one of claims 1-3, wherein the sliding element is made of maintenance free material.

5. The joint arrangement according to any one of claims 1-4, wherein the sliding element has a cuboid shape with longitudinal edges and transverse edges forming a rectangular face functioning as a sliding surface.

6. The joint arrangement according to any one of claims 1-5, wherein the sill beam comprises a bottom plate, wherein the sliding element has a smaller width as the bottom plate.

7. The joint arrangement according to any one of claims 1-6, wherein the joint arrangement consists of two sliding elements arranged on opposite sides of and at an equal distance away from the pin.

8. The joint arrangement according to any one of claims 1-7, wherein a counter plate is arranged between the sliding element and the bogie corner.

9. The joint arrangement according to any one of claims 1-8, wherein a locking plate is arranged between the sliding element and the sill beam.

10. The joint arrangement according to any one of claim 1-9, wherein the joint arrangement further comprises a protective cover covering the sliding element and configured to protect the sliding element from UV light, rain and debris.

11. The joint arrangement according to any one of claim 1-10, wherein the joint arrangement further comprises a claw arrangement, comprising a claw, connected to a side of the sill beam, wherein the claw arrangement is configured to prevent rotation of the sill beam about the pin over a predetermined limit.

12. The joint arrangement according to claim 11, wherein a tip of the claw extends under a top plate of the bogie corner without touching the top plate.

13. The joint arrangement according to claim 11 or 12, wherein the claw arrangement comprises a shaft plate, wherein the shaft plate is connected to the claw.

14. The joint arrangement according to any one of claims 11-13, wherein the claw arrangement further comprises a fin protruding from a side wall of the sill beam.

15. The joint arrangement according to claim 14, wherein the fin is at- tached to a counterpart, perpendicular to the fin, and the counterpart is parallel to the shaft plate, wherein the shaft plate and the counterpart are connected to each other by fasteners.

16. A crane, such as an automated stacking crane (ASC), a rail mounted gantry (RMG) crane, a ship-to-shore (STS) crane, or a shipyard crane, comprising a joint arrangement according to any one of claims 1-15.

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