EP3680194B1 - Coupling piece for connecting two stacked containers on board ships - Google Patents

Description

The invention relates to a coupling piece for connecting two stacked containers on board ships with: a first coupling projection which can be inserted into a lower corner fitting of the upper container and can be pre-locked there; a second coupling projection which is designed to engage in an upper corner fitting of the lower container in a coupled state; a support surface on a locking head of the first coupling projection, which is designed to rest in the coupled state on an inner edge on the lower corner fitting of the upper container; and a spacer of the first coupling projection such that the coupling piece can only be inserted into the lower corner fitting of the upper container in a certain orientation.

Such a coupling piece is from the EP 1 784 348 B1 known to the applicant.

Coupling pieces of this type are used on deck (on the hatch cover) of a ship to connect containers transported as a container stack with one another. The containers in the lowest layer and, with the help of lashing bridges, sometimes also containers in higher layers, are additionally secured with lashing bars. Often, however, the coupling pieces are the only means of securing the containers in higher elevations against loss during sea transport.

When stowing (loading) the containers, the stevedore first inserts a coupling piece with its first (upper) coupling projection into the four lower corner fittings of a container to be loaded and locks them there. The container is now hoisted onto the deck of the ship by a crane (container bridge) and placed there on an already stowed container. The second (lower) Coupling projections in the four upper corner fittings of the already stowed container. When the container is now stacked, the second coupling projections engage in the upper corner fittings of the already stowed, now lower container and in this way secure the new stowed, now upper container against being lost during sea transport. This state is referred to as the coupled state in the context of the present disclosure.

The above mentioned EP 1 784 348 B1 relates to a so-called fully automatic twistlock (FAT). With this type of coupling piece in particular, it is important that the coupling pieces are always inserted and pre-locked in a certain orientation by the stevedore in the lower corner fitting of the upper container, as otherwise the containers may no longer separate from each other when unloading (unloading) permit. To this end, the EP 1 784 348 B1 a spacer is provided, which prevents the coupling pieces from being inserted and pre-locked in a wrong orientation.

In the coupled state, the coupling piece engages around the edges of the corner fittings in a C-shape. Tensile forces on the coupling piece due to lifting forces on the container, which are induced by the sea, therefore lead to the coupling piece bending open elastically. Furthermore, the corner fittings of the container are also elastically deformed. With particularly high forces, the sum of these two elastic deformations can lead to the coupling piece disengaging from the corner fitting (so-called opening effect) and, as the worst consequence, the container is lost or even seafarers are harmed. The so-called classes therefore limit the maximum permissible tensile force, known in specialist circles as the pull-out force, for a specific coupling piece.

From the DE 10 2011 087 042 B3 , the DE 10 2016 004055 B3 , the DE 10 2009 035 201 A1 and the DE 20 2012 101 261 U1 are each coupling pieces with a pull-out force comparable to that of the coupling piece according to the EP 1 784 348 B1 known.

Proceeding from this, the invention is based on the problem of developing a coupling piece of the type mentioned at the beginning in such a way that the opening effect is reduced and consequently the pull-out force can be increased.

To solve this problem, the coupling piece according to the invention is characterized in that the spacer has a bearing surface which is aligned with the bearing surface of the first coupling projection and is also designed to rest on the inner edge of the lower corner fitting of the upper container in the coupled state, so that the bearing surface of the first coupling projection and the bearing surface of the spacer form a uniform bearing surface for the locking head and the total length of the locking head is greater than the length of the straight side edge of an elongated hole in the corner fitting.

The bearing surface of the first coupling projection is accordingly enlarged by the bearing surface of the spacer. The two bearing surfaces form a common bearing surface for the first coupling projection on the inner edge of the corner fitting. This reduces the pressure on the edge of the lower corner fitting of the upper container with the same tensile force. Furthermore, this pressure also has an effect closer to an inner wall of the corner fitting, as a result of which the lever arm is reduced. The edge of the corner fitting is therefore less deformed. In this way, the opening effect can be reduced and thus the pull-out force increased. With a given payload, this increases the safety reserve of the coupling piece. Conversely, the payload could be increased with the same safety reserve. Furthermore, due to the lower deformation, the vertical play of the coupling piece in the container corners is also reduced, which also has a positive effect. At the same time, a prototype has surprisingly shown that it can still be easily inserted into the corner fitting and pre-locked there.

Further constructive configurations of the coupling piece according to the invention, which facilitate the threading of the upper coupling projection into the lower corner fitting of the upper container or further improve the carrying behavior, are the subject of the dependent claims.

Fig. 1

ein Kuppelstück mit den Erfindungsmerkmalen in Seitenansicht vorverriegelt in einem unteren Eckbeschlag eines oberen Containers,

Fig. 2

den Eckbeschlag gemäß Fig. 1 in Vorderansicht,

Fig. 3

den Eckbeschlag gemäß Fig. 1 in Draufsicht,

Fig. 4

eine schematische Darstellung einer Krafteinleitung in das Kuppelstück gemäß Fig. 1,

Fig. 5

eine schematische Darstellung der Krafteinleitung in das Kuppelstück gemäß Fig. 1 unter der Last.

The invention is explained below with reference to an embodiment shown in the drawing. In the drawing show:

Fig. 1

a coupling piece with the features of the invention in a side view pre-locked in a lower corner fitting of an upper container,

Fig. 2

the corner fitting according to Fig. 1 in front view,

Fig. 3

the corner fitting according to Fig. 1 in plan view,

Fig. 4

a schematic representation of a force introduction into the coupling piece according to Fig. 1 ,

Fig. 5

a schematic representation of the introduction of force into the coupling piece according to Fig. 1 under the load.

The figures show a coupling piece 10, specifically a so-called fully automatic twist lock (FAT) for connecting two containers stacked on top of one another on board ships at their corner fittings.

The coupling piece 10 has a first, upper coupling projection 11, which is inserted by the stevedore on the quay in a lower corner fitting 12 of an upper container, not shown in detail. For this purpose, the container is lifted by a crane. The stevedore then inserts the upper coupling projection 11 of a coupling piece 10 into each of the four corner fittings 12. The container is now hoisted on board the ship by the crane and set down on an already stowed container (lower container). A second, lower coupling projection 13 threads into an upper corner fitting of the lower container and comes into engagement with this corner fitting fully automatically. When the container is cleared, the lower coupling projection 13 automatically disengages from the upper corner fitting of the lower container when the upper container is lifted by a crane is raised. Nevertheless, the coupling pieces 10 reliably secure the container against being lifted off and lost during sea transport. This is for example in the EP 1 534 612 B1 , the one mentioned at the beginning EP 1 784 348 B1 or the EP 2 892 828 B1 described in more detail. The latter EP 2 892 828 B1 shows a lower coupling projection which corresponds to the lower coupling projection 13 of the present coupling piece 10.

In the present case, a stop plate 14 is provided between the upper coupling projection 11 and the lower coupling projection 13, which, as an alternative to the shape shown, can only have the shape of a bead that engages in a groove that is created by chamfers on the elongated holes of the corner fittings 12 if these lie directly on top of one another.

Starting from the stop plate 14, the upper coupling projection 11 has a shaft 15 with which the upper coupling projection 11 extends through an elongated hole 16 on the corner fitting 12. The length D of the shaft 15, measured from the top of the stop plate 14, is adapted to the thickness C of a lower plate 17 in which the elongated hole 16 is arranged. As a rule, the length D of the shaft 15 is the same or slightly longer than the thickness C of the plate 17 ( Fig. 2 ). The length D should not be too great compared to the thickness C, since this would also increase the vertical play of the coupling piece 10. Ideally, D = C, at least within the usual manufacturing tolerances. In this case, the vertical play of the upper coupling projection 11 in the corner fitting 12 is equal to "zero" (D - C = 0).

A locking head 18, which protrudes to one side, namely to the same side as a locking lug 19 on the lower coupling projection, adjoins the shaft 15 on an (upper) side opposite the stop plate 14. When the containers are stacked on top of one another (in the coupled state), the coupling piece 10 thus encompasses the corner fittings with its locking head 18 and the locking nose 19 in a C-shape. In the Figures 4 and 5 this is indicated by a hatched area. A lower support surface 20 on the locking head 18 rests on the plate 17. The locking head 18 protrudes with respect to the shaft 15 by a width B, which a distance B1 from a longitudinal edge of the elongated hole 16 to an adjacent side wall 21 of the elongated hole 16 is matched. In other words, the width B is matched to a width B1 of an edge of the plate 17 around the elongated hole 16, which lies under the support surface 20. Specifically, B = B1 or slightly smaller. In general, B and B1 should be dimensioned such that a lateral play of the shaft 15 with respect to the elongated hole 16 corresponds approximately to the play between the locking head 18 and the side wall 21. Ideally, both games are the same.

Furthermore, in Fig. 3 an imaginary circle 22 is drawn, the diameter E of which has a center point of the elongated hole 16 (intersection point of the two axes 23 and 24) as the center point. Arcuate end faces 25 of the elongated hole 16 also follow the contour of this circle 22, as in FIG Fig. 3 is easy to see. The diameter E therefore corresponds to the greatest length of the elongated hole 16.

As also in Fig. 3 As can be seen, the locking head 18 projects, starting from the axis 24, by a dimension F which corresponds to half the diameter E. In this case, a lateral edge 26 of the locking head 18 forms a tangent to the imaginary circle 22. Alternatively, F can also be greater than half the diameter E. So F ≥ E / 2 applies.

The coupling piece 10 described so far also has a spacer 27, which prevents the coupling piece 10 from being installed the wrong way round. This is mentioned in the introduction EP 1 784 348 B1 described in more detail. However, the present spacer 27 differs in essential points from this prior art:
The present spacer 27 for its part has a bearing surface 28 which is aligned with the bearing surface 20 of the locking head 18. The support surface 28 of the spacer 27 thus also rests on the plate 17 of the corner fitting 12. In other words, the bearing surfaces 20 and 28 form a uniform bearing surface for the locking head 18 on the plate 17. In other words, the length A of the locking head 18 reduced by the spacer is equal to the total length L of the Locking head extended. The total length L is greater than the length of the straight lateral edges (in this case also A) of the elongated hole 16 and in the present case even greater than E.

In the exemplary embodiment shown, the spacer tapers away from the actual locking head 18 towards its free end in a wedge shape, as in FIG Fig. 3 recognizable. Specifically, an outer side surface 29 of the spacer 27 (pointing towards the side wall 21) is arranged at an angle Z to the side wall 21 (which runs parallel to the longitudinal axis 24 of the elongated hole 16). An inner side surface 30 (pointing away from the side wall 21) runs at an angle Y to the longitudinal axis 24 of the elongated hole 16. As can be seen from the drawing, the outer side surface 29 and the inner side surface 30 converge in a wedge shape. The angles Y and Z can be the same or different from one another. The angles Y and Z are each between 0 ° and 30 °. They are preferably 10 °.

An upper side 31 of the spacer 27 also slopes away from the actual locking head 18 towards the free end like a ramp, namely at an angle W ( Fig. 1 ). This angle W then again be between 0 ° and 30 °, 10 ° being particularly preferred here too.

Finally, a common upper side 32 of the locking head 18 and of the spacer 27 falls off towards the outside (towards the side wall 21) like a ramp, namely at an angle X ( Fig. 2 ). This angle X is between 30 ° and 60 °, 45 ° being particularly preferred.

The angles Y and Z also contribute to the easier threading of the upper coupling projection 11 into the elongated hole 16. The angles W and Z essentially serve to save weight.

As in Fig. 1 can still be seen, the shaft 15, adjacent to the stop plate, has a shaft shoulder 33, which in particular is longer than the rest of the shaft 15. Seen in plan view, this shaft extension 33 has a contour which the The contour of the elongated hole 16 corresponds and thus reduces the play of the coupling piece 10 with respect to the elongated hole 16, especially in the longitudinal direction (axis 24) of the elongated hole 16, without hindering the insertion of the upper coupling projection 11 into the corner fitting 12.

List of reference symbols:

10

Coupling piece

11th

Coupling projection

12th

Corner fitting

13th

Coupling projection

14th

Stop plate

15th

shaft

16

Long hole

17th

plate

18th

Locking head

19th

Locking tab

20th

Support surface

21

Side wall

22nd

circle

23

axis

24

axles

25th

Front side

26th

Edge

27

Spacer

28

Support surface

29

Side face

30th

Side face

31

Top

32

Top

33

Shaft heel

A.

Edge length of the elongated hole 16

B.

broad

B1

distance

C.

Plate thickness

D.

Shaft length

E.

diameter

F.

Measure

L.

length

W.

angle

X

angle

Y

angle

Z

angle

Claims (7)

1. A coupling piece (10) for connecting two containers stacked on top of each other aboard of ships, comprising:

   a first coupling projection (11), insertable and pre-lockable in a lower corner fitting (12) of the upper container;

   a second coupling projection (13), adapted to engage in an upper corner fitting of the lower container in a coupled state;

   a bearing face (20) at a locking head (18) of the first coupling projection (11), which is adapted to rest on an inner rim at the lower corner fitting (10) of the upper container in the coupled state; and

   a spacer (27) of the first coupling projection (11), such that the coupling piece (10) is insertable in the lower corner fitting (12) of the upper container in a particular orientation only;

   characterized in that the spacer (27) comprises a bearing face (28) which is aligned with the bearing face (20) of the first coupling projection (11) and also adapted to rest on the inner rim of the lower corner fitting (12) of the upper container in the coupled state, such that the bearing face (20) of the first coupling projection (11) and the bearing face (28) of the spacer (27) form a uniform bearing face for the locking head (18) and the overall length (L) of the locking head (18) is larger than the length (A) of the straight edges on the sides of an oblong hole (16) in the corner fitting (12).
2. The coupling piece according to claim 1, characterized in that the spacer (27) comprises an outer lateral face (29) and an inner lateral face (30) which converge in a wedge-shaped manner.
3. The coupling piece according to claim 2, characterized in that the outer lateral face (29) extends at a first angle (Y), in particular of 0° to 30°, preferably 10°, and the inner lateral face (30) extends at a second angle (Z), in particular of 0° to 30°, preferably 10°, to a longitudinal axis (24) of the upper coupling projection (11), wherein the first angle (Y) and the second angle (Z) are equal to or different from each other.
4. The coupling piece according to any of claims 1 to 3, characterized in that the locking head (18) of the upper coupling projection (11) projects laterally by a measure (F) which is larger than or equal to a semi-length (E) of the oblong hole (16) in the corner fitting (12) at the longest position thereof (F ≥ E/2).
5. The coupling piece according to any of claims 1 to 4, characterized in that a breadth (B) of the bearing face (20) is equal to or slightly smaller than a breadth (B1) of a rim of a plate (17) of the corner fitting (12).
6. The coupling piece according to any of claims 1 to 5, characterized by a stop plate (14) which is joined by a shaft (15) of the first coupling projection, wherein a length (D) of the shaft measured from an upper side of the stop plate (14) to the bearing face (20) is adapted to the thickness (C) of a lower plate (17).
7. The coupling piece according to claim 6, characterized in that the length (D) of the shaft (15) is equal to the thickness (C) of the plate (17).

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