WO2019004889A1

WO2019004889A1 - Locking device for cargo containers and method

Info

Publication number: WO2019004889A1
Application number: PCT/SE2018/000015
Authority: WO
Inventors: Torbjörn KARLSSON
Original assignee: TAN, Guofang
Priority date: 2017-06-26
Filing date: 2018-06-26
Publication date: 2019-01-03
Also published as: SE1730165A1

Abstract

A locking device (10) for interlocking a pair of opposing doors (2, 3) on a cargo container (1). It comprises a rotatably mounted latch hook (30) moved in and out of a holding position by a handle mechanism (40) via a toggle mechanism (50) and locked by a lock actuator (70) via a pawl arm (60). A handle bar (42), toggle base (51) and pawl holder (62) are parts with a common rotational centerline (91) accommodated in a track form (37). The toggle mechanism or pawl arm is accommodated in a recess shape (38). A method for assembling a locking device (10) for interlocking a pair of opposing doors (2, 3) on a cargo container (1) by: assembling a latch hook (30), a toggle mechanism (50) and a pawl arm (60) into a coherent unit (90) and assembling said coherent unit for movability in and out of the different positions.

Description

LOCKING DEVICE FOR CARGO CONTAINERS AND METHOD

Technical field

The present innovation relates to a locking device for

interlocking a pair of opposing doors on a cargo container. It also relates to a method for assembling a locking device for interlocking a pair of opposing doors on a cargo container. The locking device comprises a rotatably mounted latch hook. The latch hook is moved in and out of a holding position by a handle mechanism via a toggle mechanism. A pawl arm is moved in and out of a locking position, where it engages with the latch hook, by a lock actuator.

Background art

Cargo containers are used for protecting goods and other content during transport and storage. They can be found on trucks and trailers, on trains, ships and in transfer or storage areas. They can be fixed on a designated carrier or movable between one or several types of carriers. They are often mass produced at low cost.

Cargo containers are usually shaped as rectangular boxes and equipped with a pair of doors on one of the short end sides. The right to open the doors of both loaded and empty containers need to be restricted and controlled in order to avoid theft,

smuggling, terrorism, espionage and so on.

New built containers are however normally not equipped with locking devices. One of the main reasons for this, is the difficulty to handle the physical keys when changing transport mode, operator, driver, or when sending the containers through customs and overseas. Another reason is that it could be costly, in relation to the overall low container price, to install the locks properly integrated inside the doors. A third reason is that the heavy duty doors need to be secured closed in a strong way. This is often done by vertical locking bars having several holding points located on the outside of the container. Traditional locking devices are therefore not needed for the purpose of keeping the container doors in place.

Instead of integrated locking devices, indicative seals are normally attached to the vertical bars during international transports. These are disposable cut-away numbered items and range from being plastic strips to more sturdy metal rivet bolts.

When the containers are used domestically, a wide range of other lock types are often applied. Loose padlocks or lock-hooks are simple to use and quick to attach. Retrofitting the container with fixed mounted lock boxes or door hasps is popular if it's going to be used for storage. Still, the above mentioned locks are located on the vulnerable outside of the container and can not really be compared to normal integrated door locks, used in many other applications, in terms of security.

With today' s improvements in information technology and better and cheaper electronic components, it should possible to start using more proper and better locking devices. The key handling problem can be avoided with electromechanical locks having virtual instead of physical keys. In a more intelligent lock, benefits additional to just keeping the doors secured can be created by collecting event data from the locking and unlocking and by automating the registration work.

There are some prior art considered to be relevant to the present invention.

US 2016/0024820 discloses an Electrically controlled locking arrangement. It has a hook-formed latch, which is manually moved in and out of its holding position and it has a pawl arm securing it in a locked position.

W09716614 discloses a Security system for cargo loading doors. it also has a hook-formed latch, but it's moved and clamped in its extended position in a single step by an actuator acting via a toggle mechanism.

One of the challenges with locking devices on cargo containers, being out of reach for long periods of time, is to conserve electric energy to get an acceptable battery lifetime. It is therefore beneficial to first move the locking latch manually, overcoming weight, friction and jamming against the doors, and then secure this latch inside the lock with smaller components and movements. With such a two-step function, it's also possible choose whether the locking function part should be enabled or not .

Another task is for the lock to ensure that both of the two doors are secured. The doors are normally opposing each other with hinges on the outer sides and meeting in the middle. A retainer plate is usually provided on one of the doors, intended for controlling the sequence in which the doors are opened and closed, one after the other. The retainer plate is often thin and easy to bend, cut or override. It is therefore beneficial for the locking device to be interlocking the two doors instead of only locking one door against the surrounding casing. A locking device having a hook latch, as opposed to a straight latch, is more suitable for preventing the two doors in such arrangement from separating if they are opened simultaneously when being

interconnected .

It would therefore be advantageous to install a two-step function locking device inside one of the doors, so that it can interlock both doors with a hook latch. Integrated in the door, it can get strength support while being protected both from the inside as well as from the outside of the container.

The prior art have toggle- and or pawl arm mechanisms extending away outside their latch hook. This makes them bulky and

difficult to fit inside the narrow hollow rectangular beam normally forming the outer edge of the door. The strength reducing openings or cut aways required for installing them also becomes large.

The prior art have several installation points, pivots for their functional mechanisms, which need to be connected either directly to the container or to an intermediate lock housing. This makes them more complex in an environment where low cost and simple reliable equipment is important.

it is thus desirable to provide a locking device which can be easily mounted and integrated in the container's door. It should be of a compact size in relation to its working range and its strength capabilities. It should be simple and cost effective, with its different parts and mechanisms having few installation points against the container or lock housing.

Summary of the invention

An object of the present invention is to provide a locking device for cargo containers which is suitable to mount and integrate in the container's door.

The above object and other objects that will be evident from the following description are achieved by a locking device according to the appended claims.

According to one aspect of the invention, a locking device for interlocking a pair of opposing doors on a cargo container comprises a latch hook being rotatably mounted in a first door and equipped with a grip surface adapted for securing a second door when being in a holding position, a handle mechanism being rotatably mounted in said first door and equipped with a handle bar arranged for transferring an applied torque to a toggle mechanism, said toggle mechanism being rotatably mounted in said first door around a toggle base and being rotatably coupled to said latch hook with a toggle mover for moving said latch hook in and out of said holding position, a pawl arm being rotatably mounted in said first door around a pawl holder and equipped with a stop surface adapted for engaging with a ratchet surface on said latch hook when being in a locking position, and a lock actuator being mounted in said first door and coupled to said pawl arm with a lock mover for moving said pawl arm in and out of said locking position. Said handle bar, toggle base and pawl holder guides and retains each other to be parts with a common rotational centerline. Said latch hook comprises a track form for accommodating said parts with a common rotational centerline in said latch hook. Said latch hook comprises a recess shape for accommodating at least one of said toggle mechanism and pawl arm. The primary function of having a common centerline is that the parts in it can hold and support each other, instead of each part having to be supported one by one in the door, for example by several individual holes for holding them. In addition to simplifying, this also makes the handle bar, toggle base and pawl holder take up less space, since they share the same place. They can thereby be fitted in a smaller unified track form in the latch hook, without destroying the strength and wanted shape of the latch hook. The handle mechanism, latch hook, toggle

mechanism and pawl arm can work overlapping each other by also utilizing a recess shape in the latch hook. They don't need to extend away outside the contour of the latch hook in any major way .

Advantages of the inventive concept is that a locking device can be provided, which is both simple and takes up little space. It can be cost effective, easily mounted and integrated in the door of a cargo container, without making too many or too large openings for the installation.

In a preferred embodiment, the locking device comprises a housing being mounted fixed in said first door and a receptacle being mounted fixed in said second door. The housing acts as an intermediate between said first door and one or more of said latch hook, handle mechanism, toggle mechanism, pawl arm and lock actuator mounted in said first door. The receptacle acts as a an intermediate between said second door and said grip surface.

Having a housing and a receptacle simplifies the installation compared to installing the various parts of the locking device directly into the doors, one by one. The housing and receptacle can also fill other functions, such as covering installation openings in the doors, fastening the locking device in different alternative ways, taking up forces or supporting the lock parts strength wise. The housing and receptacle serves as intermediates and the choice to install parts in them, or in the doors or in both places, may depend on the layout of the installation work, among many things.

In a preferred embodiment, the latch hook is rotatably mounted with a latch bolt and said track form is shaped as a radial slot having the same center as said latch bolt. The toggle mechanism and pawl arm are mainly accommodated inside an outer contour of said latch hook.

Latch hooks are sometimes mounted to have a rotating but not only radial movement, they can follow a path as they turn.

However, a good way to mount a latch hook of a locking device to get a rotating motion in this case, is to simply attach it to a latch bolt. This type of fastening is easy to get strong, considering that the latch hook is the main locking part between the doors. Using a latch bolt gives a simple radial motion easy to match with the shape of a track form. With the track form shaped as a slot through hole, it is easy to retain the said parts with a common centerline in it and couple them on opposite sides of the latch hook. This design of the latch hook enables overlapping it with the toggle mechanism and pawl arm, for them to take up a limited space which is not significantly larger than the outer contour of the latch hook itself.

In a preferred embodiment, the toggle mechanism comprises at least one toggle pivot rotatably coupled with two toggle arms. The toggle base, toggle mover and toggle pivot are in a close to straight line when said toggle mechanism being in said holding position .

A toggle mechanism arranged with two coupled arms is a suitable way to transfer the torque and movement from the handle mechanism to the latch hook. When the three pivots are aligned in a closed to straight line, the latch hook will be clamped and it will not be movable by other means than turning the handle mechanism.

Furthermore, the force from the toggle mechanism and thereby the torque in the latch hook will be relatively larger in the beginning and end of its movement, close to the end positions, where it is more needed to overcome jamming and to secure a correct position. A third benefit with the toggle mechanism is to separate the rotation center of the latch hook, which usually is suitable to place close to the side of the door beam, from the rotation center of the handle mechanism, which usually is suitable to place in the center of the door beam. In a preferred embodiment, the lock actuator is an

electromechanical device comprising a actuator piston arranged to move linearly relative an actuator housing. The actuator piston is rotatably coupled in said lock mover and the actuator housing is mounted in said first door with a actuator installation bolt.

It is advantageous to use simple and reliable components in the harsh environments in which cargo containers can be found and a linear moving actuator as described is a proven mechanism, for example often used in car door locks. An electromechanical actuator can be controlled from the outside of the container by signals transmitted to an internal electric control unit and be powered by internal batteries. With the pawl arm being rotatable and the lock actuator being linear moving, it is suitable to mount the lock mover to the actuator piston using a rotatable coupling, wherein said connection can follow the intended movement without jamming.

In a preferred embodiment, the handle mechanism comprises a turn handle being located on the outside of the container and adapted for receiving a torque. The latch hook, toggle mechanism, pawl arm and lock actuator are located inside a door beam of said first door.

The purpose of the turn handle is to be moved manually by a person from the outside of the container, thereby saving electric energy from the battery. The applied torque is transferred from the outside to the inner protected lock parts. The locking device is integrated in the first door.

In a preferred embodiment, the common rotational centerline is formed and guided by:

- said handle bar comprising a centered outer torque transfer shape connecting to a corresponding inside shape of said toggle base,

- said toggle base comprising an outer round shape rotatably coupling to a corresponding inside shape of said pawl holder,

- said toggle base comprising an outer round shape rotatably guiding to said track form of said latch hook, - said toggle base comprising an outer round shape rotatably coupling to a corresponding hole in said first door, and by

- said handle bar comprising an centered outer shape rotatably coupling to a corresponding hole in said first door.

By just having outer and inner surfaces corresponding to each other, like holes and bars with common centerlines, a simple arrangement is created where the parts will guide and retain each other. When the surrounding hole part turns, the inner bar part can be still and act as a guiding bearing or the other way around. One hole in the first door will hold three parts, the handle mechanism, the toggle mechanism and the pawl arm. One track form in the latch hook will hold the same three parts before the assembly in the first door.

According to another aspect of the invention, a method is provided for assembling a locking device for interlocking a pair of opposing doors on a cargo container. Said method comprising the steps of:

- Assembling a latch hook, a toggle mechanism and a pawl arm into a coherent unit by:

- placing at least one of said toggle mechanism and pawl arm in a recessed shape in said latch hook,

- coupling a rotatable toggle mover of said toggle mechanism to said latch hook, and

- mounting a toggle base of said toggle mechanism and a pawl holder of said pawl arm into a common rotational centerline and in a track form of said latch hook.

- Assembling said coherent unit for movability in and out of a holding position and in and out of a locking position by:

- rotatably mounting said latch hook to a first door with a latch bolt,

- mounting a handle bar of a handle mechanism in said common rotational centerline with said toggle base and said pawl holder, and

- mounting a lock actuator to a lock mover of said pawl arm. One purpose of first assembling the latch hook, toggle

mechanism and pawl arm into a coherent unit, is to facilitate an easy and simple second step of the assembly into the door of the container. When the toggle base and pawl holder are together inside the track form, instead of being loose and uncontrolled outside it, it is significantly easier to align them on the inside with the handle bar being mounted from the outside of the container. Other advantages in handling the three parts as a coherent unit is a simplified logistic of the parts, a

possibility to test and perform quality control of the unit independently and an easier replacement of spare parts.

Preferably, the step of assembling said coherent unit for movability in and out of a holding position and in and out of a locking position, comprises mounting said handle mechanism and said lock actuator in said first door.

This is advantageous since the fastening of the locking device against the first door is then combined with the mounting of the handle mechanism and the lock actuator in relation to the locking device. The two parts initiating movements, gets a permanent position from where they can act.

Preferably, the step of assembling said coherent unit for movability in and out of a holding position and in and out of a locking position, comprises mounting one or more of said latch hook, handle mechanism, toggle mechanism, pawl arm and lock actuator to a housing acting as an intermediate to the first door .

Using a housing simplifies the installation because inserting individual parts into and securing them inside the door beam of the first door can be difficult and ought to be avoided.

Brief description of drawings

Preferred embodiments will in the following be described in more detail with reference to the accompanying drawings, in which

Figure 1 shows a perspective view of a cargo container with a coupling device according to the invention.

Figure 2 shows a perspective view of the coupling device in a cut out part of the door beams . Figure 3 shows a front view of the coupling device with the door beams in cross section.

Figure 4 shows a perspective view of the coupling device.

Figure 5 shows an exploded view of the coupling device in perspective.

Figure 6, 7 and 8 shows in three front views a sequence of the coupling device without housing and receptacle. In figure 6 the latch hook is in an inner position, out of its holding position, and the pawl arm is in a non-engaging position, out of its locking position. In figure 7 the latch hook is in a holding position and the pawl arm is still in a non-engaging position. In figure 8 the latch hook is in a holding position and the pawl arm is in a locking position.

Figure 9 shows an exploded view of the coherent unit in perspective.

Figure 10 shows a perspective view of the coherent unit.

Figure 11 shows a front view of the coherent unit with the outer contour of the latch hook in thicker lines. Detailed description of preferred embodiments

The invention will now for the purpose of exemplification be described in more detail with reference to the accompanying drawings. An embodiment of a locking device 10 for interlocking a pair of opposing doors 2, 3 on a cargo container 1 according to the invention, as shown in the different drawings, usually comprises the main elements of a rotatable latch hook 30, a handle mechanism 40, a toggle mechanism 50, a pawl arm 60 and a lock actuator 70.

Figure 1 shows a suitable installation location for a locking device 10 for interlocking a first right door 2 with a second left door 3 on a cargo container 1. The illustrated container has a commonly available design with double doors at the short end side. The doors are opposing each other with hinges 4 on opposite outer peripheral edges. Vertical locking bars 6 are attached to the doors and hold them in place when closed, in this case against eight holding points on the surrounding container casing. A retainer plate 5 is attached to the outside of the first door 2 and overlaps the second left door 3. Since the retainer plate is accessible and can be bent from the outside, it is advantageous that the locking device secures both of the two doors. And since both doors can be opened simultaneously together, in an outward swing motion risking to release a straight latch design, it is advantageous when the locking device is equipped with a

hook-shaped latch holding the two doors together.

The two doors 2, 3 here comprises an inner area of corrugated sheet metal surrounded by a frame of four beams, in accordance with many commonly used containers. This design may vary because materials and details are not specified in the ISO standards for shipping containers, because smoother thicker wall materials are preferred for trailer containers, or because insulation panels are used in thermal containers, among several reasons. The central area around the locking device can be seen in figure 2. A first door beam 7 of the first door 2 and a second door beam 8 of the second door 3 are cut out in the shown view and their hollow rectangular section shapes are visible. A rubber gasket often covers the gap between the two doors, but to improve visibility, it is not shown in this or in any other illustration. The gap between the doors can be large compared to doors occurring in other non-mobile applications. Due to the significant forces the container often is exposed to, the doors can shift significantly relative each other, both vertically and in the container's transverse direction. This in conclusion requires the lock to cover a large tolerance area for locking, but provides a limited space within the door beam 7 when it's in a retracted position.

A front view projection of the locking device 10 location in the first door beam 7 and how its latch hook 30 extends into the second door beam 8 when in a holding position can be seen in figure 3. The following figures 4 and 5 shows the locking device in the same state but without having the door beams visible.

In this embodiment of the invention, the locking device comprises a housing 20 and a receptacle 21. The purpose of them is to act as intermediates between the other parts of the locking device and the door beams 7, 8 of the doors 2, 3, providing easier installation, stronger securing and more reliable

functions. Their installation features are best seen in figure 5. They can be fastened to the doors using the mount screws 23 and the attached mount threads 22. They have face plates 24 for covering the openings made in the door beams for the installation and they are equipped with side plates 25 for support and strengthening. The housing 20 have hollow rivets 26, acting as spacers and assisting in securing its two side plates 25 in relation to each other. By attaching installation bolts 27 from the inside of the door, through the rivets 26 located in the door beam, to the back of a cover housing 45 on the outside of the container being part of the handle mechanism 40, the mentioned parts can be secured in the door 2 and relative each other.

Neither the installation bolts 27 nor the mount screws 23, will be accessible from the outside of the container when the doors are closed. Furthermore, the side plates 25 of the housing 20 have holes for rotatably mounting the latch hook 30 with a latch bolt 32, the toggle mechanism 50 with its toggle base 51, as well as the lock actuator 70 with an actuator installation bolt 74.

The advantages of using the housing 20 and receptacle 21 are that the handling and assembling of several loose parts can be avoided during the installation, that the strength can be optimized through increased opportunities to adjust the design of the installation and pivot points, and that holes and connections can be made in a more controlled fashion, in a factory instead of outside in the field. The openings through the face plates 24 can be adapted to the movement of the latch hook 30 and the outside shape of the face plates 24 can be adapted for matching

appropriate installation openings in the doors 2, 3. Without the housing 20 and receptacle 21, a non optimal compromise would be required between these shapes and functions in a simple cut out opening in the door beam 7, 8.

On the other hand, the housing 20 and receptacle 21 are not entirely necessary to achieve the basic function of locking the doors. It can be envisaged that they are omitted to save money. The latch hook 30 can simply enter an opening in the second door 3 and hook against its inside. The latch bolt 32, toggle base 51 and actuator installation bolt 74 can be installed directly in the first door 2. The handle mechanism 40 can be mounted in the first door 2 and secured with the same installation bolts 27 in the cover housing 45. For clarity, both visually and

conceptually, the housing 20 and receptacle 21 are not depicted in the figures 6 through 11.

In the preferred embodiment, a turn handle 44 is mounted in the first door 2 and accessible from the outside of the cargo container, as shown in fig 2. It has a shape suitable for being rotated manually and it is the only part of the locking device 10 intended to be operated by hand. The turn handle 44 is fixed connected in the same centerline to a handle bar 42, as shown in fig 5, which transfers the movement from the outside to the inside of the first door beam 7. The previously mentioned cover housing 45 is essentially located between the turn handle 44 and the handle bar 42, allowing them to rotate in it. The handle bar 42 is fastened on the inside of the container with a washer 46 and a spring clevis 47, or a similar arrangement allowing the handle bar to rotate but not to be pulled out. It has a square section shape suitable for transferring its torque to a toggle base 51 of a toggle mechanism 50.

The toggle mechanism 50 acts as an intermediate coupling between the handle mechanism 40 and the latch hook 30. Rotating the turn handle 44 will move the latch hook 30. In the shown embodiment, they are arranged to work in the same direction - with a clockwise rotation of the turn handle 44 giving a

clockwise rotation of the latch hook 30.

The movements in the locking device 10 are best seen in figure

6, 7 and 8, with figure 6 to 7 showing how the toggle mechanism 50 changes the position of the latch hook 30.

The toggle base 51 has a square hole, where the square section of the handle bar 42 is fitted. The toggle base 51 is fixed attached to a first toggle arm 52. The first toggle arm 52 is rotatably coupled to a second toggle arm 53 by a toggle pivot 54. The second toggle arm 53 is rotatably coupled to the latch hook 30 with a toggle mover 55.

In figure 6, the toggle base 51 has been turned to its

counter-clockwise end position. Further rotation in this

direction is stopped by the first toggle arm 52 being against an inside surface of the latch hook. Further counterclockwise rotation can also be stopped by the latch hook 30 here halting against the door or housing, for example against the first door beam 7 inner surface indicated by the dotted line. The toggle mechanism 50 is in an extended state, with the toggle mover 55 pushed out away from the toggle base 51. Thereby the toggle mover 55 has moved the latch hook 30 counter-clockwise around the latch bolt 32. The latch hook 30 is retracted into the first door 2, away from its holding position and not engaging with the second door 3.

In figure 7, the toggle base 51 has been turned 180 degrees relative to figure 6, to its clockwise end position. Further rotation in this direction is stopped by the toggle base 51 being against the second toggle arm 53. Further clockwise rotation can also be stopped by the latch hook 30 here halting against the door or housing, for example against the first door beam 7 inner surface indicated by the dotted line. The toggle mechanism 50 is in a retracted state, with the toggle mover 55 pulled close the toggle base 51. Thereby the toggle mover 55 has moved the latch hook 30 clockwise around the latch bolt 32. The latch hook 30 is extended to its holding position, with its grip surface 34 securing the second door 3 as shown in figure of figure 3, 4 and 5.

In the clockwise and counterclockwise end positions, the toggle mechanism 50 will clamp the latch hook 30. The toggle mover 55, the toggle pivot 54 and the toggle base 51 are in an essentially straight line and a force from the latch hook 30 will therefore not result in a torque around the toggle base 51 or a movement of the toggle mechanism 50. In practice, balancing on a straight line is difficult and designing a slight over-rotation towards the previously described stopped end positions is done to accomplish the clamping effect.

After the latch hook 30 has been moved to its holding position, as shown in figure 7, it should be locked in place as shown in figure 8. This action is suitably initiated by a radio signal coming from the outside of the container, being processed in an electrical control and battery unit 11, to start a movement of an lock actuator 70. The lock actuator 70 can be an

electromechanical device commonly used in car door locks, as illustrated in the drawings, having an actuator piston 72 moving linear in and out in relation to a actuator housing 71.

Alternatives to this arrangement can for example be a passive radio identification or infrared signal for the communication, or an actuator motor or solenoid carrying out an rotational instead of a linear movement. A linear lock actuator 70 as depicted is best suited to be rotatably mounted in order to get the pawl arm 60 to perform a rotational movement. The lock actuator 70 is therefore rotatably mounted in the first door 2 using an actuator installation bolt 74 and moves the pawl arm 60 by being rotatable coupled in a lock mover 66. The two installation points 74 and 66 have rotational properties to make the movements match, but they could alternatively just as well be designed to slide, for example as pins moving in elongated holes. The actuator housing 71 could even be fixed installed in several points in the door 2 if the flexibility of the lock actuator 70 is sufficient or if the allowed movement in the lock mover 66 is enough.

When the pawl arm 60 is being moved at the lock mover 66, it turns around the pawl holder 62, being in the same rotational centerline 91 as the handle bar 42 and the toggle base 51, and moves a stop surface 64 to a locking position. In the locking position, the stop surface 64 engages with a ratchet surface 36 on the latch hook 30 and stops the the latch hook 30 from rotating. The contact between the ratchet surface 36 and the stop surface 64 is adapted to the relation between the rotation points 62 and 32 so that the grip doesn't loosen. With a

counterclockwise torque in the latch hook 30, trying to open it, the contact between the surfaces 36, 64 will strive to move the pawl arm 60 counterclockwise, further into its locking position. The retention in the achieved ratchet locking mechanism results in a pulling force between the stop surface 64 and the pawl holder 62 locking the latch hook 30.

In order to save space, reduce the number of installation points and simplify the assembly, the latch hook 30, the toggle mechanism 50 and the pawl arm 60 are assembled into a coherent unit 90, as shown in figure 9, 10 and 11.

The latch hook 30 is the primary interlocking part between the first 2 and second door 3. It needs a thickness capable of withstanding the many different forces it is exposed to in a variety of situations and also a precise shape for handling its functional features. A suitable way of making such a latch hook 30 is by dividing it into a plurality of plate segments 33, as best seen in figure 9. By using plate segments 33, it is also easy to form cavities with complicated shapes such as the recess shape 38 and track form 37 in the latch hook 30.

Comparing figure 9 and 10, shows the concept of how the coherent unit 90 is assembled. The toggle base 51 with a fixed attached toggle arm 52, is first rotatably coupled to the second toggle arm 53 with a toggle pivot 54. The two arms 52, 53 are suitably placed one on top of the other. The toggle pivot 54 is suitably a rivet being pressed to form retaining heads on its opposite sides, stopping separation of the two arms but allowing them to rotate in relation to each other. The two joined arms 52, 53 of the toggle mechanism 50 are then placed in the recessed shape 38 and between the outer of the plate segments 33. The toggle base 51 is placed to extend through the track form 37 on the outer of the plate segments 33. Then the plate segments 33 are moved together and the second toggle arm 53 is coupled to the latch hook 30 with the toggle mover 55. The toggle mover 55 is suitably a rivet being pressed to form retaining heads on its opposite sides, stopping separation of the plate segments 33 but allowing the second toggle arm 53 to rotate in relation to the latch hook 30. Other rivets, similar to the toggle mover 55 in that they stop separation of the plate segments 33, can be placed in other places on the latch hook 30 if needed.

When the plate segments 33 are joined together, the toggle mechanism 50 is retained to its intended movements in the latch hook 30. The toggle base 51 can only move back and forth and turn inside the track form 37. The two toggle arms 52, 53 can only extend and retract between their end positions inside the recess shape 38. The toggle mover 55 can only turn relative the latch hook .

The pawl holder 62 is then rotatably coupled to the toggle base

51, with them having a common rotational centerline 91. The pawl holder 62 is suitably formed as a hole fitting around an outer cylindrical shape of the toggle base 51. This embodiment enables them to guide and retain each other in a simple way. The pawl arm 60 is suitably formed by one piece on each side of the latch hook 30 being joined together by an intermediate embodiment of the stop surface 64. The stop surface 64 is suitably a rivet being pressed to form retaining heads on its opposite sides, stopping separation of the two arm pieces .

The pawl holder 62 and the toggle base 51 can rotate relative the other, but not escape from each other. The pawl arm 60 can move into its locking position, where the stop surface 64 engages with the ratchet surface 36, when the toggle mechanism 50 is retracted and the toggle base 51 is in the outer end of the track form 37. The latch hook 30, toggle mechanism 50 and pawl arm 60 are overlapping each other and can mainly be accommodated within the outer contour 39 of the latch hook, as shown in figure 11.

As appreciated by a person skilled in the art, the mentioned fastening by rivets being pressed to form retaining heads on opposite sides, may be designed in a different manner. A common way to design such a fastener, is by screwing together an inner threaded bolt with an outer threaded bolt with their heads from opposite outer sides. It is also possible to imagine the toggle mechanism 50 and the pawl arm 60 changing places, so that the pawl arm instead would works inside and the toggle mechanism outside of the latch hook 30. After the coherent unit 90 has been prepared, the next step in the assembly process of the locking device 10, is to assemble said coherent unit 90 in the first door 2. The coherent unit 90 is inserted into the first door beam 7 and secured with a latch bolt 32. The latch hook 30 is thereby rotatable in the first door 2 but without anything controlling its position. The toggle base 51 and lock mover 66 are however not completely unruly since they are being held in the coherent unit. The turn handle 44, cover housing 45 and handle bar 42 of the handle mechanism 30 has also been pre assembled. The handle bar 42 is inserted through a front hole in the door beam 7, into the toggle base 51 and through a rear hole in the door beam 7, and comes out on the inside of the container. This is probably best visualised in figure 5. The handle bar 42 has an outer square shape matching an inner square shape of the toggle base 51. The square shape is suitable for transferring a torque between the parts, but other alternative forms could be used for achieving the same purpose. The handle bar 42, toggle base 51 and pawl holder 62 becomes part of a common rotational centerline 91. The actuator piston 72 of the lock actuator 70 is coupled to a the pawl arm 60 with the lock mover 66. The lock mover 66 is suitably a rivet being pressed to form retaining heads on its opposite sides, allowing rotation and being similar to the rivets earlier discussed. The actuator housing 71 is mounted in the first door 2 to provide a counter to the moving piston 72.

In the described assembled embodiment, turning the turn handle 44 will move the latch hook 30 in and out of holding position and moving the actuator 70 will move the pawl arm 60 in and out of a locking position. The handle mechanism 40, toggle mechanism 50, pawl arm 60 and latch hook 30 work efficiently together,

overlapping each other in mainly the same are space, by utilizing the common rotational centerline 91, the track form 37 and the recess shape 38. The assembly was simplified by utilizing the compact coherent unit 90 consisting of several parts and the common rotational centerline 91 merging several installation points .

Claims

1) A locking device (10) for interlocking a pair of opposing doors (2, 3) on a cargo container (1), said locking device comprising a latch hook (30) being rotatably mounted in a first door (2) and equipped with a grip surface (34) adapted for securing a second door (3) when being in a holding position, a handle mechanism (40) being rotatably mounted in said first door and equipped with a handle bar (42) arranged for transferring an applied torque to a toggle mechanism (50) , said toggle mechanism being rotatably mounted in said first door around a toggle base (51) and being rotatably coupled to said latch hook with a toggle mover (55) for moving said latch hook in and out of said holding position, a pawl arm (60) being rotatably mounted in said first door around a pawl holder (62) and equipped with a stop surface (64) adapted for engaging with a ratchet surface (36) on said latch hook when being in a locking position, and a lock actuator (70) being mounted in said first door and coupled to said pawl arm with a lock mover (66) for moving said pawl arm in and out of said locking position, said locking device

c h a r a c t e r i z e d i n t h a t said handle bar (42) , toggle base (51) and pawl holder (62) comprising a common rotation centerline (91) around which they are guiding and retaining each other, said latch hook (30) comprising a track form (37) for accommodating said parts (42, 51, 62) with a common rotational centerline (91) in said latch hook (30), and said latch hook (30) comprising a recess shape (38) for accommodating at least one of said toggle mechanism (50) and pawl arm (60) .

2) A locking device according to claim 1, further comprising a housing (20) being mounted fixed in said first door (2) and a receptacle (21) being mounted fixed in said second door (3), said housing acting as an intermediate, by providing means for

installation and mounting, between said first door and one or more of said latch hook (30), handle mechanism (40), toggle mechanism (50), pawl arm (60) and lock actuator (70) mounted in said first door, said receptacle acting as a an intermediate, by providing means for installation and strengthening, between said second door and said grip surface (34) .

3) A locking device according to any of the preceding claims, wherein said latch hook (30) being rotatably mounted with a latch bolt (32), said track form (37) being shaped as a radial slot having the same center as said latch bolt, and said toggle mechanism (50) and pawl arm (60) being mainly accommodated inside an outer contour (39) of said latch hook. 4) A locking device according to any of the preceding claims, wherein said toggle mechanism (50) comprising at least one toggle pivot (54) rotatably coupled with two toggle arms (52, 53) , and wherein said toggle base (51) , toggle mover (55) and toggle pivot being in a close to straight line when said toggle mechanism being in said holding position.

5) A locking device according to any of the preceding claims, wherein said lock actuator (70) being an electromechanical device comprising a actuator piston (72) arranged to move linearly relative an actuator housing (71) , said actuator piston being rotatably coupled in said lock mover (66) and said actuator housing being mounted in said first door with a actuator

installation bolt (74) .

6) A locking device according to any of the preceding claims, wherein said handle mechanism (40) comprising a turn handle (44) being located on the outside of the container and adapted for receiving a torque, and wherein said latch hook (30) , toggle mechanism (50) , pawl arm (60) and lock actuator (70) being located inside a first door beam (7) of said first door (2) .

7) A locking device according to any of the preceding claims, wherein said common rotational centerline (91) is formed and guided by said handle bar (42) comprising a centered outer torque transfer shape connecting to a corresponding inside shape of said toggle base (51), by said toggle base (51) comprising an outer round shape rotatably coupling to a corresponding inside shape of said pawl holder (62), by said toggle base (51) comprising an outer round shape rotatably guiding to said track form (37) of said latch hook (30), by said toggle base (51) comprising an outer round shape rotatably coupling to a corresponding hole in said first door (2), and by said handle bar (42) comprising an centered outer shape rotatably coupling to a corresponding hole in said first door.

8) A method for assembling a locking device (10) for interlocking a pair of opposing doors (2, 3) on a cargo container (1), c h a r a c t e r i z e d i n the steps of:

- assembling a latch hook (30) , a toggle mechanism (50) and a pawl arm (60) into a coherent unit (90) by placing at least one of said toggle mechanism (50) and pawl arm (60) in a recessed shape (38) in said latch hook (30), by coupling a rotatable toggle mover (55) of said toggle mechanism (50) to said latch hook (30), and by mounting a toggle base (51) of said toggle mechanism (50) and a pawl holder (62) of said pawl arm (60) into a common rotational centerline (91) and in a track form (37) of said latch hook (30),

- assembling said coherent unit (90) for movability in and out of a holding position and in and out of a locked position by

rotatably mounting said latch hook (30) to a first door (2) with a latch bolt (32), by mounting a handle bar (42) of a handle mechanism (40) in said common rotational centerline (91) with said toggle base (51) and said pawl holder (62), and by mounting a lock actuator (70) to a lock mover (66) of said pawl arm (60).

9) A method for assembling a locking device according to claim 8, wherein the step of assembling said coherent unit for movability in and out of a holding position and in and out of a locked position, comprises mounting said handle mechanism (40) and said lock actuator (70) in said first door (2) . 10) A method for assembling a locking device according to claim 8 or 9, wherein the step of assembling said coherent unit for movability in and out of a holding position and in and out of a locked position, comprises mounting one or more of said latch hook (30), handle mechanism (40), toggle mechanism (50), pawl arm (60) and lock actuator (70) to a housing (20) acting as an

intermediate, by providing means for installation and mounting, to said first door (2) .