WO2008110030A1

WO2008110030A1 - Method and apparatus for separating engagement devices

Info

Publication number: WO2008110030A1
Application number: PCT/CN2007/000774
Authority: WO
Inventors: Robert Arthur Mills; Qifan Bao; Ghee Hua Ng; Zhan Min Tong
Original assignee: Nsl Engineering Pte Ltd
Priority date: 2007-03-12
Filing date: 2007-03-12
Publication date: 2008-09-18

Abstract

An engagement assembly (25) for mounting to a first head block (35A) so as to engage a second head block (35B), said assembly comprising at least one mounting bracket (45A, B) for mounting the assembly to the first head block; a plurality of telescopically extendable members (57A, B) each connected at a first end to the at least one mounting bracket, a second opposed end of each telescopically extendable member being extendable away from said first head block; a plurality of engagement portions (50A, B) in communication with the second ends such that extension of the second ends consequently extends the engagement portions, said engagement portions adapted to engage the engagement brackets mounted to the second head block; wherein on engagement, relative movement of the head blocks (35A, B) in the horizontal plane is subject to extension of the telescopically extendable members (57A, B) and relative vertical movement is independent of the telescopically extendable members.

Description

N2007/000774

Method and Apparatus for Separating Engagement Devices

Field of the Invention

The invention relates to the movement of shipping containers and other intermodal devices used for the transport of freight. More specifically the invention relates to engagement devices, such as head blocks mounted to spreaders, said head blocks typically being detachable from said spreaders. Further still the invention relates to those engagement devices, such as spreaders and head blocks, used for the movement of multiple containers at one time.

Background

The economics of processing shipping containers is directly proportional to the volume of containers through a shipping yard. To enhance the flow of containers, certain devices have been developed whereby two containers may be moved at one time and so at least at this stage doubling the rate of movement of the containers.

For instance, where access to the containers is limited, it is particularly advantageous to use apparatus that will fit within a confined space, such as limited to a single head block and spreader, with apparatus that includes two head blocks and spreaders. To this end it would be further advantageous if two head blocks could be used for two spreaders engaging two containers and further that the spreaders or head blocks could be separated so as to deal with the two containers as individuals rather than collectively.

A system has been proposed to achieve this involving arms projecting from one head block having ball shaped ends and mounted to a second head block is a mechanical device for engagement that comes together to grip the balls in a pincer-type action, creating a ball joint between the two devices. Thus by activating the arms to move to position and further to have the pincers to move into position also, the head blocks can be engaged and disengaged accordingly.

However, in order to engage the two head blocks, the tolerance for the pincers to engage the balls of the projecting arms is of the order of 50mm. One can imagine two head blocks having spreaders attached thereto in an outdoor environment where wind can affect the motion of the spreaders. To engage the head blocks within a tolerance of 50mm would be an extremely difficult activity and certainly time consuming detracting from the benefits offered by the dual head blocks.

Other more complex systems are known such as those having projecting arms formed from parallelogram linkages. Whilst useful said systems are more complex to manufacture and require a greater number of moving parts which could lead to further maintenance. It would therefore be advantageous to have a head block that could be engaged and disengaged more easily than the above mentioned system.

Statement of Invention

Therefore, in a first aspect the invention provides an engagement assembly for mounting to a first head block so as to engage a second head block, said assembly comprising: at least one mounting bracket for mounting the assembly to the first head block; a plurality of telescopically extendable members each connected at a first end to the at least one mounting bracket, a second opposed end of each telescopically extendable member being extendable away from said first head block; a plurality of engagement portions in communication with the second ends such that extension of the second ends consequently extends the engagement portions, said engagement portions adapted to engage engagement brackets mounted to the second head block, wherein; on engagement, relative movement of the head blocks in the horizontal plane is subject to extension of the telescopically extendable members and relative vertical movement is independent of the telescopically extendable members.

In a second aspect, the invention provides a method of engaging a first head block and a second head block, comprising the steps of: extending a plurality of telescopically extendable arms mounted at first ends to the first head block towards the second head block, said telescopically extendable anus having second ends in communication with a plurality of engagement portions such that extension of the second ends consequently extends the engagement portions; said engagement portions engaging engagement brackets mounted to the second head block; permitting selective relative movement of the head blocks in the horizontal plane and free relative vertical movement.

As a broad concept the invention provides for a mechanical device mounted to a first head block which extends to grip a fixed portion of an adjacent second head block, and following engagement permits free relative vertical movement between the head blocks. Moreover by providing telescopically projecting arms the number of moving parts is reduced as is the complexity of the mechanism, possibly leading to reduced costs and reduced maintenance.

Brief Description of Drawings

It will be convenient to further describe the present invention with respect to the accompanying drawings that illustrate possible arrangements of the invention. Other arrangements of the invention are possible and consequently the particularity of the accompanying drawings is not to be understood as superseding the generality of the preceding description of the invention.

Figure 1 is an isometric view of the engagement assembly according to one embodiment of the present invention;

Figure 2 is an isometric view of the engagement assembly of Figure 1 mounted to a pair of head blocks; Figures 3 A to 3 C are plan views of the engagement assembly of Figure 1;

Figures 4A and 4B are isometric views of the engagement assembly of Figure 1 separating two engaged head blocks;

Figures 5A and 5B are elevation views of a chain and sprocket arrangement according to an embodiment of the present invention;

Figures 6A and 6B are plan views of the engagement assembly of Figure 1 offsetting to two adjacent head blocks;

Figure 7 is a plan view of the engagement assembly of Figure 1 skewing two adjacent head blocks; Figures 8 A to 8D are elevation views of the engagement assembly of Figure 1 showing relative vertical movement of adjacent head blocks;

Figures 9A and 9B are schematic views of the hydraulic circuit used to operate the engagement assembly according to one embodiment of the present invention.

Description of Preferred Embodiment

Figure 1 shows an overall view of a container engagement assembly 5 comprising a pair of head blocks 10 mounted to two spreaders 2OA, B. In this embodiment the spreaders 2OA, B are twin container spreaders and thus each spreader 2OA, B is mounted to a pair of containers 15A to D and thus the entire container engagement assembly 5 is mounted to four containers 15A to D and thus carrying the full capacity of this particular arrangement. Figure 2 shows the head blocks 35 A, B of the container engagement assembly 5 whereby the head blocks 35 A, B are engaged through an engagement assembly 25 according to one embodiment of the present invention. In this case the engagement assembly 25 comprises two extendable members 3OA, B which are mounted to one head block 35 A and extending outwards towards a second head block 35B. At extreme ends of the extendable members 3OA, B is a lateral engagement member 65 for engaging the second head block 35B so as to both connect the head blocks 35 A, B as well as control the relative position of the head blocks 35A, B as will be discussed.

Figure 3 A shows a detailed view of a portion of the engagement assembly 25.

The assembly 25 comprises parallel extension members 57A, B which are extendable from the first head block 35 A to which the assembly 25 is mounted. The extension is achieved by respective hydraulic rams 55 A, B mounted to a portion of the extension members 57 A, B. At the extreme ends of the extension members 57 A, B is an engagement member 65 which is positioned in a normal orientation at right angles to the extension member 57A, B. The engagement member 65, however, is mounted to the extension member 57 A₅B with rotational joints such that the engagement member may be rotated within the horizontal plane subject to the relative extension of the two extension members 57A,B. The engagement member 65 further includes a bi- directional hydraulic ram 66 which is arranged to extend and retract engagement lugs 50A,B which are positioned at extreme ends of the engagement assembly 65. It should be noted that the engagement lugs 50A,B are offset from the longitudinal axis of the engagement assembly 65, said offset being on a side of the engagement assembly 65 opposed to that of the first head block 35A. In this embodiment, the actual lugs 50A₅B are directed along an axis parallel to, but not co-linear with, the longitudinal axis of the engagement assembly 65 with the direction of said lugs arranged so as to be facing each other and thus directed inwards rather than directed outwards. In light of this arrangement, an embodiment having the lugs co-linear with the engagement assembly 65 is also possible, as is an arrangement whereby the lugs are directed outwards.

The engagement assembly 25 further includes engagement brackets 45A,B which are mounted to a second head block 35B. Each of said brackets 45A,B are hooked shaped, in cross section, with the concave portion directed outwards so as to receive the engagement lugs 50A,B both in position and shape. Said engagement brackets 45A,B further are shaped such that the concave portion of the hooked shape forms a channel along which the engagement lugs 50A,B may slide without hindering said movement. It follows that in order to prevent hindrance of the sliding action said channel is directed along a vertical axis such that when said lugs 5 OA₅B are engaged with said brackets 45A₅B that, so long as the relative position of the lugs is maintained, said head blocks may freely move relative to each other along a vertical axis through sliding of said lugs along said channel.

Figures 3 A to 3 C show sequential steps for the engagement assembly to engage the brackets 45 A₅B and so connect the two adjacent head blocks 35A₅B. Accordingly Figure 3A shows the engagement assembly only partially extended and thus said head blocks are yet to be engaged. It should be noted that, in this view, the bi-directional ram 66 of the engagement member is such that the engagement lugs 50A₅B are fully extended. Figure 3B shows a further sequential step in the engagement process whereby the engagement members 57A,B have fully extended so as to bring the engagement member 65 into proximity with the second head block 35B. It will be noted that the lugs 50A,B are proximate with the engagement brackets 45A,B but are yet to be retracted by the bi-directional ram so as to fully engage said brackets. As with Figure 3 A, whilst the engagement member 65 is proximate to the second head block 35B, because the lugs 50A,B have not engaged the brackets 45A₅B, the two head blocks are yet to be in connection.

Figure 3 C shows the actual engagement of the first head block 35 A to the second head block 35B. Here the engagement member 65 is still proximate to the second head block 35B and, further, the bi-directional ram 66 has retracted the lugs so as to be in engagement with the brackets 45A₅B- In this engagement position the head blocks 35A₅B are in fixed relation within the horizontal plane through the engagement of the lugs and the brackets, but as mentioned previously are free to move in the vertical axis through sliding of said lugs within the chamiel formed by said brackets.

Once engaged, the engagement assembly 25 is capable of performing a number of actions leading to the change of relative positions of the two head blocks 35A₅B. Whilst the engagement assembly 25 cannot control the change in relative position along a vertical axis it can, however, adjust the position within certain limits within the horizontal plane. This includes lateral adjustments such as separating the head blocks or drawing the head blocks together so as to bring the containers in close proximity or even into contact. Further, the engagement assembly can form an offset, that is, shift the relative position of the head block 35A,B along parallel axes. Further still, the engagement assembly can cause a skew, that is, a relative rotation of the head blocks 35 A₅B within the horizontal plane.

Figures 4A and 4Bshow progressive views of the separation function of the engagement assembly 25. As shown in Figure 4A, the head blocks are proximate to each other, though not in contact, and thus the engagement assembly is only partially extended. As shown in Figure 4B, as the extension members 57A,B further extend, the head blocks 35A,B are further separated so as to reach a maximum stroke.

In order to reach the full extension there is a limitation of the extension arms 57A,B as to the maximum extension they can provide. It follows that in a simple construction, the stroke of the ram 55 will limit the length for which the extension arm can extend. Figures 5 A and 5B show a second embodiment whereby the hydraulic ram 55 is mounted to a first sub-member 75 of the extension member. A second sub- element 70 forms part of the extension member, with a chain and sprocket arrangement 80, 85 A, B, 86, 90 separating the two sub-members 70, 75. The arrangement comprises a fixed arm 74 to which the chain 86 is mounted 90. The first sub-member includes sprockets 85A, B at opposed ends about which the chain travels. The chain 86 is further mounted 80 to the second sub-member 75. In this embodiment as the hydraulic ram 55 extends 95, there is a consequent extension 100 of the sub-member 75. Driving the first sub-member 75 a distance X rotates the chain 86. As the chain travels about the sub- member 75, this causes a subsequent compound movement 2X of the second sub- member 70. As shown in Figure 5B, the compound effect is further demonstrated whereby the first sub-member 75 undergoes movement 4X which is leads to the movement 8X of the second sub-member 70.

Figures 6 A and 6B show the offset function of the engagement assembly 25, achieved by the bi-directional ram 66 within the engagement member 65. As stated previously, engagement of the lugs with the engagement brackets is achieved by mutually retracting the lugs so as to engage the brackets. After engagement, and as shown in Figure 6, if a first lug 50A is further retracted by the bi-directional ram 66 but a second lug 50B is extended, this has the effect of moving the lugs 50A,B in the same direction. Whilst in engagement with the engagement brackets 45A,B, this applies a force so as to shift 110, the second head block 35B in the same direction. As shown in Figure 6B, to offset the head blocks in the other direction, the direction of the lugs is reversed so that the second lug 50B is retracted above the first lug 5OA extended. Thus by controlling the bi-directional rams 66, this has the effect of offsetting the position of the head blocks 35 A, B relative to each other along parallel axes.

Figure 7 shows a further function of the engagement assembly whereby the extension members 57 A₅B have differential extension, whereby the first extension member 57 A has more fully extended than the second extension member 57B. This has the effect of rotating 130 the two head blocks relative to each other and so skewing said head blocks by a desired amount. As mentioned previously the engagement assembly 25 has no control over the relative vertical position of the head blocks 35 A, B. This is achieved by lifting or lowering the head blocks separately so as to achieve the results. Figures 8 A to 8D show various relative positions in the vertical axis of the two head blocks starting at Figure 8A whereby the engagement assembly 25 is located at the upper portion of the bracket 45. As the second head block 35B is raised 135, the engagement lug slide within the bracket 45 and is shown at a mid point in Figures 8B and at a lower point 140in Figure 8C as the lifting of the second head block 35B progresses. As a safety measure, or merely as a more convenient way of disengaging the head blocks 35 A and 35B, further lifting of the second head block 35B disengages the head blocks by permitting the engagement lug to slide out of contact with the bracket 45. Thus, if a rapid disengagement is required, all that is required is to lift, or alternatively, lower the first head block 35A to cause disengagement, thus providing a safety feature.

Figure 9 A shows a schematic view of the bi-directional actuator 65 in one embodiment of the present invention. Here a first ram 144 in communication with the first engagement portion 5OA is directly influenced by hydraulic oil entering a first chamber 143 and an intermediate chamber 142. The oil entering the first chamber 143 enters through Inlet A 150 with oil entering the intermediate chamber 142 through Inlet B 155. A second ram 147 in communication with the second engagement portion 50B is influenced by a second chamber 145 and the intermediate chamber 142 whereby hydraulic oil entering the second chamber 145 enters through Inlet C 160. Possible permutations of oil entering or exiting the inlets and so entering the first, second and intermediate chambers 143, 142, 145 are shown in Figure 9B. In the lookup table of Figure 9B, "1" indicates oil entering the chamber, "-1" indicates oil leaving the chamber and "0" indicates the chamber being closed and therefore incompressible.

The first permutation 170 has hydraulic oil entering the first chamber 143 through the Inlet A 150, oil exiting the intermediate chamber 142 and oil entering the second chamber 145 and so indicating a "1" for Inlet A, "-1" for Inlet B, "1" for Inlet C. As indicated in the schematic drawing relating to the first permutation 170, this will cause the rams 144 and 147 to be directed inwards and thus retract the first and second engagement portions 50A, B. This action is required for the lateral engagement member 65 engaging the engagement brackets 45A, B.

The second permutation 175 indicates for Inlets A, B and C a "1", "0" and "-1". The consequence of this arrangement leads to the rams 144 and 147 to be directed to the right which if the head blocks 35 A, B were in engagement would lead to an offset similar to that shown in Figure 6B, but in the opposite direction.

The third permutation 180 indicates the inlets being "-1", "1", "-1" and so the first and second chambers 143, 145 having oil exiting the chamber with oil entering the intermediate chamber 142. This would lead to the rams extending outwards and so extending the engagement portions 5OA, B which would lead to a selective disengagement of the head blocks 35A, B. The fourth permutation 185 has for Inlets A, B and C "1", "-1", "0" which would have the second chamber 145 fixed in volume, oil exiting the intermediate chamber 142 but oil entering the first chamber 143. Thus the first ram 144 would move to the right whilst the second ram 147 would stay in a fixed position. This might be, for instance, part of an automatic sequence whereby the second engagement portion 5OB may already be in engagement with the engagement bracket 45B and so bringing the first engagement portion into contact with the engagement bracket 45A.

The fifth permutation 190 shows the reverse of the fourth permutation 185 and so may be an adjustment in order to re-engage the second head block.

Claims

Claims :

1. An engagement assembly for mounting to a first head block so as to engage a second head block, said assembly comprising: at least one mounting bracket for mounting the assembly to the first head block; a plurality of telescopically extendable members each connected at a first end to the at least one mounting bracket, a second opposed end of each telescopically extendable member being extendable away from said first head block; a plurality of engagement portions in communication with the second ends such that extension of the second ends consequently extends the engagement portions, said engagement portions adapted to engage engagement brackets mounted to the second head block, wherein; on engagement, relative movement of the head blocks in the horizontal plane is subject to extension of the telescopically extendable members and relative vertical movement is independent of the telescopically extendable members.

2. The engagement assembly according to claim 1 wherein the telescopically extendable members comprise a plurality of nested sub-members in sliding engagement with adjacent sub-members.

3. The assembly according to claim 1 or 2 wherein each of the telescopically extendable members are biased by a linear actuator, said actuator being any one or a combination of: pneumatic, hydraulic or electric actuators.

4. The assembly according to claim 1 wherein the telescopically extendable members include a plurality of sub members such that adjacent sub- members are engaged through a sprocket and chain arrangement.

5. The assembly according to claim 4 wherein said adjacent sub-members extend along axes parallel to an axis of extension of said telescopically extendable members.

6. The assembly according to claim 4 wherein the chain for said sprocket and chain arrangement is driven such that adjacent sub-members are capable of relative linear movement and said chain is driven as a result of movement of the actuator.

7. The assembly according to any one of claims 2 to 6 wherein each telescopically extendable member has a total stroke equivalent to a multiple of the stroke of the actuator, said multiple being equivalent to the number of sub-members within said telescopically extendable member.

8. The assembly according to any one of the preceding claims, further including a lateral engagement member connected to each of the second ends such that extension of the second ends consequently extends the lateral engagement member, said engagement portions mounted to the lateral engagement member.

9. The assembly according to claim 8, wherein said lateral engagement member adapted to extend the engagement portions in opposed directions along an axis parallel to a longitudinal axis of the second head block, and further adapted to retract the engagement portions along the same axis in order to engage engagement brackets of said second head block.

10. The assembly according to any one of the preceding claims, wherein the at least one mounting bracket includes a single base from which each extendable arm extends.

11. The assembly according to any one of claims 1 to 9, wherein each arm having an individual base, said bases collectively forming the mounting means.

12. The assembly according to any one of the preceding claims, wherein the engagement brackets include brackets mounted to the second head block, said brackets including vertically arranged channels.

13. The assembly according to any one of claims 2 to 12, wherein the lateral engagement means includes an actuation means directed in two opposed directions.

14. The assembly according to claim 13, wherein said actuation means include two actuators each acting on a respective engagement portions.

15. The assembly according to claim 13, wherein said actuation means includes a single bi-directional actuator, opposed ends of said bi-directional actuator acting on respective engagement portions.

16. The assembly according to any one of the preceding claims, further including a control system adapted to automatically activate the extendable arms.

17. The assembly according to claim 16, wherein said control system adapted to automatically activate the lateral engagement means.

18. The assembly according to any one of the preceding claims, wherein the engagement portions are located adjacent opposed ends of the lateral engagement member.

19. The assembly according to claim 12, wherein the engagement portions include lugs adapted to fit and slide within said channels.

20. The assembly according to any one of the preceding claims, wherein engagement is maintained subject to the free relative vertical movement being in the range of ± 2 m from a central engagement position.

21. The assembly according to claim 20, wherein engagement is maintained subject to the free relative vertical movement being in the range of ± 0.5 m from a central engagement position.

22. A method of engaging a first head block and a second head block, comprising the steps of: extending a plurality of telescopically extendable arms mounted at first ends to the first head block towards the second head block, said telescopically extendable arms having second ends in communication with a plurality of engagement portions such that extension of the second ends consequently extends the engagement portions; said engagement portions engaging engagement brackets mounted to the second head block; permitting selective relative movement of the head blocks in the horizontal plane and free relative vertical movement.

23. The method according to claim 22, wherein the engaging step comprises the step of retracting the engagement portions in convergent directions along an axis parallel to a longitudinal axis of the first head block in order to engage the engagement brackets.

24. The method according to claim 22, further comprising the steps of extending the telescopically extendable arms, and selectively separating the head blocks, after the engaging step.

25. The method according to claim 22 further comprising the steps of extending at least one telescopically extendable arm whilst maintaining the position of at least one other telescopically extendable arm so as to place the head blocks in a skew relative position, after the engaging step.

26. The method according to claim 23 further comprising the steps of retracting one engagement portion and extending another engagement portion, such that movement of the engagement portions are in the same direction along the axis parallel to a longitudinal axis of the first head block, so as to place the head blocks in an offset relative position, after the engaging step.