The present invention relates in one aspect to a key box for safe-keeping small items, such as mechanical and/or electronic key items, access cards, credit cards, or the like. According to a particular aspect, the key box comprises a first member and a second member, the first member and the second member together defining a secure space, wherein the second member is moveable with respect to the first member between a CLOSED position preventing access to the secure space and an OPEN position allowing access to the secure space; wherein the key box further comprises a lock mechanism adapted for locking the first and second members in the CLOSED position.

According to a further aspect, the key box may be dimensioned as a mobile strong- box for the safe-keeping of small valuables, such as for use in a private household or a hotel room. Such a mobile strong box may be e.g. dimensioned so has to hold mobile electronic devices, wallets, passports, or the like.

According to a yet further aspect the key box is adapted for wall mounting, such as for mounting into a wall or for fixation onto a support structure like a wall. BACKGROUND OF THE INVENTION

Key boxes for safe keeping of access items, such as keys or access cards, are known. Such key boxes are used e.g. by workmen, service businesses in the care or the cleaning sector, or rescue workers in emergencies, or real estate agents to obtain access to keys/access cards for flats or properties merely by use of one common code or key. Examples of such key boxes are e.g. known from US patents US 5768921 , US 8375752, US 5794465, or from the published US patent applica- tion US 2016/0180621. However, very often such boxes suffer from a lack of strength of the locking mechanism making it rather insecure to keep access items or similarly sized important valuables in such small, mobile strongboxes. Furthermore, very often such small boxes also suffer from an insecure authentication system, such as having to type in a code on a key pad on the front side, which may be diffi cult to do in a discrete manner. Yet furthermore, such visible authentication interfac- es on the outside of the box are often susceptible to vandalism. One improved key box addressing at least some of these issues is known from the published interna- tional patent application WO 2015/107006.

Nevertheless, there is still a need for key boxes providing good protection against intrusion, which have a compact and space saving locking mechanism, and/or which may be operated in a remote controlled manner in a power saving and reliable man- ner.

One object of the present of the present invention is therefore to provide a key box that overcomes at least some of the drawbacks set forth above or provides an alter- native to existing key boxes. More particularly, one object of the invention is to pro- vide a strong locking system for a key box, which is safeguarded against unauthor- ized access by mechanical means, by electronic means, or by mechanical and elec- tronic means.

SUMMARY OF THE INVENTION

According to one aspect, the invention provides a key box as defined by claim 1 , with advantageous embodiments as defined by the dependent claims and disclosed herein.

According to some embodiments, a key box comprises a first member and a second member, the first member and the second member together defining a secure space, wherein the second member is moveable with respect to the first member between a CLOSED position preventing access to the secure space and an OPEN position allowing access to the secure space; wherein the second member compris- es peripheral side walls; wherein the key box further comprises a lock mechanism fixed to the first member; wherein the lock mechanism comprises a locking plate, the lock mechanism being adapted to rotate the locking plate about a rotation axis be- tween a LOCK position and an UNLOCK position; wherein the locking plate corn- prises a plurality of cams, each cam projecting in a different radial direction away from the rotation axis and being arranged to engage the second member at a corre- sponding engagement point on the side walls when the second member is in the CLOSED position and the locking plate is in the LOCK position. The term‘inwardly’ as used herein is defined as pointing in a direction towards the inside of the secure space, such as in a direction towards the rotation axis of the locking plate. The term‘outwardly’ as used herein is defined as pointing in a direc- tion towards the outside of the secure space, such as in a direction away from the rotation axis of the locking plate. The term‘axial’ as used herein refers to directions essentially parallel to the rotation axis of the locking plate. The term‘radial’ as used herein refers to directions essentially perpendicular to the rotation axis of the locking plate, the term‘lateral’ as used herein refers to directions parallel to radial directions. A lateral plane is therefore a plane essentially perpendicular to the rotation axis of the locking plate.

The LOCK and UNLOCK positions are two different angular positions of the locking plate. When the key box is closed, and the locking plate is in the LOCK position the key box is locked, i.e. opening of the key box and access to the secure space is prevented. When the locking plate is then rotated by means of the locking mecha- nism into the UNLOCK position the key box is unlocked, thus allowing to move the first and second members apart so as to yield access to the secure space. Most preferably, the locking mechanism is arranged inside the secure space.

The locking effect is achieved by a plurality of cams projecting in different radially outward directions from the periphery of the locking plate, wherein the cams are engagement elements adapted to engage the second member at respective en- gagement points. The locking plate is thus adapted to simultaneously engage the second member at multiple points, thereby bringing about a strong interlocking ef- fect keeping the first and second members together in the CLOSED position. Typi- cally the engagement points are flange portions on the side walls, such as inwardly projecting flange portions.

Each cam points in a different respective direction: i.e. at least a first cam and a second cam are provided, the first cam projecting radially outward in a first direction away from the rotation axis, and the second cam projecting radially outward in a second direction away from the rotation axis, wherein the second direction is differ- ent from the first direction. Preferably, the locking plate is arranged to block movements of the second member with respect to the first member in an axial direction essentially parallel to the rota- tion axis. The locking plate is configured for exerting blocking forces against forces for movements in an axial direction. Typically, such a blocking force is directed per- pendicular to the locking plate, or at least has a vector component in the axial direc- tion. Furthermore, such a vector component is typically a major component of the blocking force.

Each of the cams is arranged to release engagement of the second member when the locking plate is brought in the UNLOCK position. The movement of the second member with respect to the first member is thus un-blocked allowing the second member to be freely moved between the CLOSED position and the OPEN position, thus providing access to the secure space, e.g. for placing items for safe-keeping therein or for retrieving items from safe-keeping.

The locking plate with multiple cams projecting in different directions thus brings about a multipoint locking effect for the movement of the first and second members with respect to each other that can be locked and released by a short angular movement of a single element. Thereby a particularly strong, yet compact locking mechanism is provided that can be driven in a particularly power saving manner with a simple rotational actuation.

The key box is for safe-keeping small items, such as mechanical and/or electronic keys, access tokens, access cards, credit cards, or similarly sized small items. The locking mechanism is particularly well-suited for small box dimensions, with a secure space adapted to the dimensions of holding a few of such small items, such as up to about 5, or up to about 10, or up to about 20, or up to about 30 credit card sized access cards; and/or up to about 10, or up to about 15, or up to about 20 mechani- cal keys as typically used for apartment or entrance doors, or other house doors; and/or up to about 5, or up to about 10, or up to about 20 car keys. Typically, such small key boxes have a total outer volume of a few litres, such as about 3I or below, or about 2I or below, or about 11 or below. Thereby a particular strong locking mech- anism is provided that makes the key box more difficult to pry open. According to some embodiments, the key box may also be dimensioned as a small/mobile “strongbox”, such as a strongbox adapted for wall mounting or a strongbox as commonly used in hotel rooms.

Further according to some embodiments of the key box the second member is at- tached to the first member by a hinge. This allows for an articulated movement of the second member with respect to the first member around a pivot axis defined by the hinge. This allows operating the key box in a simple and intuitive manner.

Further according to some embodiments of the key box, a pivot axis of the hinge is arranged along one of the side walls of the second member, and essentially parallel thereto, e.g. parallel to one of the edges of a polygon/rectangle defined by the side walls as seen in a lateral plane.

Further according to some embodiments of the key box, the plurality of cams corn- prises at least two cams, wherein a first one of the plurality of cams is arranged to engage the second member at a first engagement point on a first side wall, and wherein a second one of the plurality of cams is arranged to engage the second member at a second engagement point on a second side wall different from the first side wall. By placing the engagement points on different side walls, a further in- creased strength of the locking action is achieved, thereby further increasing the resistance of the key box against forced entry as compared to known key boxes.

Further according to some embodiments of the key box, the locking plate comprises at least three cams, wherein a third one of the plurality of cams is arranged to en- gage the second member at a third engagement point on a third side wall different from the first and second side walls. Thereby a yet further increased security and enhanced resistance against forced entry is achieved. This embodiment is particu- larly useful for a hinged embodiment with four side walls where the hinge is ar- ranged at a fourth side wall different from the first, second, and third side walls, since all side walls are thereby secured.

Advantageously according to some embodiments of the key box, at least one of the engagement points is arranged on a side wall opposite to the hinge. Further advan- tageously one or more further engagement points are arranged on adjoining side walls next to the side wall opposite to the hinge. Thereby a particularly sturdy lock- ing mechanism is achieved, since multiple points of engagement of the locking mechanism work together with the hinge so as to secure the first and second mem- bers together in the CLOSED position.

Advantageously according to some embodiments of the key box, the peripheral con- tour of the second member is shaped as a polygon, wherein edges of the polygon are defined by the side walls of the second member as seen in a lateral plane per- pendicular to the rotation axis of the locking plate. The polygon has n edges, such as at least three, four, five, six, seven, eight or even more edges.

Advantageously according to some embodiments of the key box, the movement is a pivoting movement around a pivot axis defined by a hinge connecting the first and second members to each other; wherein the pivot axis is arranged in a lateral plane, parallel to an edge defined by one of the side walls. Further advantageously for a second member with a polygonal shaped peripheral contour with n edges, the lock- ing plate has (n-1 ) cams, each of the (n-1 ) cams being configured for engaging the second member at a different side wall which is also different from the hinged side wall. Further advantageously, a connecting line between an engagement point on a side wall and the rotation axis is essentially perpendicular to said side wall as seen in projection onto a lateral plane. Thereby a distance of the rotation axis to the point of cam engagement is minimized while placing the engagement points at the pe- riphery of the second member. Thereby the strength of the locking engagement is promoted yet achieving a compact locking mechanism.

Advantageously according to some embodiments of the key box, the movement is a sliding movement along a direction parallel to the rotation axis. Further advanta- geously for a second member with a polygonal shaped peripheral contour with n edges, the locking plate has n cams, each of the n cams being configured for en- gaging the second member at a different side wall. Thereby a strong locking effect is achieved, since all side walls are engaged by the locking plate. Further advanta- geously, a connecting line between an engagement point on a side wall and the rotation axis is essentially perpendicular to said side wall as seen in projection onto a lateral plane. Thereby a distance of the rotation axis to the point of cam engage- ment is minimized while placing the engagement points at the periphery of the sec- ond member. Thereby the strength of the locking engagement is promoted yet achieving a compact locking mechanism.

Advantageously according to some embodiments of the key box the cams of the locking plate in the UNLOCK position point away from (directions) perpendicular to the side walls, such as/preferably towards corners of the polygon/rectangle. Thereby a simple construction allowing for the release of the second member is achieved.

Further according to some embodiments of the key box, a cam engagement radius of a cam is defined by a distance of the corresponding engagement point to the rota- tion axis of the locking plate, wherein the cam engagement radius is the same for all cams. More particularly, the cam engagement radius corresponds to the distance between the rotation axis and the point on the cam where the cam engages the second member when the second member is in the CLOSED position and the lock- ing plate is in the LOCK position. The rotation axis is thus located at equal distances from the engagement points. Thereby an advantageous even distribution of the blocking forces is achieved.

Alternatively according to some embodiments of the key box, a locking plate with different cam engagement radii for different cams may be conceived, e.g. in order to adapt the locking mechanism to certain box geometries.

Advantageously according to some embodiments the key box is dimensioned for the safe keeping of small items only as mentioned above. Advantageously according to such embodiments for the safe-keeping of only small access items like keys, access cards and the likes, a cam engagement radius is less than or about 10cm, less than or about 8 cm, less than or about 6 cm, or less than or about 4 cm, wherein smaller cam engagement radii allow for providing a sturdy locking mechanism, which makes it particularly difficult to pry open the key box, in particular as the engagement points are arranged at the side walls of the second member. A good locking strength is thus achieved. Further according to some embodiments of the key box the first member is a base plate, preferably adapted for wall mounting. Further advantageously, the first mem- ber is a base plate adapted for carrying the locking mechanism thereon on the side facing towards the inside of the key box, i.e. the locking mechanism is preferably arranged inside the secure space.

Further according to some embodiments of the key box the side walls of the second member enclose the first member as seen in radial directions, when the second member is in the CLOSED position. The side walls of the second member thus en- close the first member as seen in a lateral plane perpendicular to the rotation axis of the locking plate when the second member is in the CLOSED position. This configu- ration makes it particularly difficult to apply any prying tools between the first and second members. This is particularly the case where the first member is configured for wall mounting, since any gap between the first and second members is thus fac- ing towards the wall and is thus hidden or at least not easily accessible to an attack- er usually coming from the front side of the key box.

Further according to some embodiments of the key box, a peripheral contour of the second member as seen in a lateral plane perpendicular to the rotation axis is de- fined by four side walls. Preferably, the peripheral contour of the second member is rectangular shaped.

According to some embodiments of a key box with a particularly strong locking ef- fect, the second member may have four side walls: wherein a first side wall corn- prises a hinge connecting the first and second members to each other for an articu- lated movement around a pivot axis; a second side wall opposite to the hinge; a third side wall: connecting first ends of the first and second side walls to each other; and a fourth side wall: connecting second ends of the first and second side walls to each other so as to close a rectangle formed by the first, second, third, and fourth side walls; and wherein an engagement point is located on each one of the second, third and fourth side walls, respectively. Further advantageously according to some embodiments, a hinge axle of the hinge connecting the first and second members is recessed with respect to the surface of the second member, in particular when the second member encloses the first member. The void between the recessed end of the hinge axle and the surface of the second member may be filled by an overlay welding, such as made of a hardfacing welding material. The weld may further ad- vantageously be made level with respect to the surface of the second member and further concealed, e.g. by means of a surface coating, thereby preventing an attack- er from easily finding and attacking the key box from the hinge axle.

Further according to some embodiments of the key box, the engagement points are formed by a flange arranged on the side walls, on the inwardly facing side thereof, i.e. on the side facing towards the secure space. This achieves a particularly strong solution that is difficult to pry open. As in combination with any of the embodiments disclosed herein, a location of the engagement points on a flange on the side walls maximizes the leverage of the locking mechanism, thereby promoting the strength of the locking effect when keeping the first and second members together in a locked engagement.

Further according to some embodiments of the key box, the flange is an inwardly projecting nose extending circumferentially along the side walls of the second mem- ber. Thereby, the flange adds a strengthening structure to the second member where the locking forces are exerted.

Further according to some embodiments of the key box one or more of the engage- ment points are formed as a recess in the side wall. Such an engagement point is easy to produce, e.g. by milling or otherwise machining the recess into the side wall at the required location only. For example, a blank for a second member may be cast as a half shell with a top wall and peripheral side walls projecting from the top wall, and subsequently the required one or more recesses for the one or more en- gagement points may be formed by milling or otherwise machining away material as necessary.

Further according to some embodiments, the key box further comprises a motor adapted to actuate the locking mechanism, an electronic control unit and a wireless communication device coupled thereto, whereby the locking mechanism is adapted to be controlled by the electronic control unit in response to user input received via the wireless communication device. The wireless communication device is adapted to communicate with an authentication device by wireless communication, prefera- bly for short range interaction, such as Bluetooth or the like.

Preferably, the wireless communication is NOT of the line-of-sight type, like IR or otherwise optical communication, as this typically requires a feed-through opening in the key box for a receiver/sensor or the optical signal, which has to be arranged on the outside of the key box, thus compromising the security of the shell formed by the first and second members of the key box. Furthermore, such a sensor/receiver lo- cated on the outside, while conceivable, makes the key box susceptible to vandal- ism.

Further according to some embodiments of the key box, the motor, the control unit, and the wireless communication device are arranged inside the secure space, in addition to the locking mechanism, which is also arranged inside.

Further according to some embodiments of the key box, the locking system further comprises a power supply arranged in the secure space. Typically, the power supply comprises a power source such as batteries, or rechargeable batteries. The power supply is for powering the locking system, including the communication device, the control unit, and the motor adapted for driving the electric locking mechanism and thus driving the locking plate into and out of engagement.

Advantageously according to some embodiments, the power supply further corn- prises an emergency jumper connector arranged to be accessible from the outside of the key box, said emergency jumper connector is useful for connecting an exter- nal power supply to power the electric locking system in case an internally located power source, such as batteries or rechargeable batteries are empty.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail by way of an advantageous em- bodiment in connection with the appended drawings, which show in

Fig. 1 a front perspective view of a key box according to one embodiment, in a CLOSED position; Fig. 2 a rear perspective view of a key box according to one embodiment, in a CLOSED position; Fig. 3 a front perspective view of a key box according to one embodiment, in an OPEN position;

Fig. 4 a further front perspective view of a key box according to one embodiment, in a CLOSED position;

Fig. 5 a cross-sectional detail of a key box according to one embodiment, showing the locking plate in the LOCK position;

Fig. 6 a cross-sectional detail of a key box according to one embodiment, showing the locking plate in the UNLOCK position;

Fig. 7 a perspective view of an electric locking mechanism according to one em- bodiment; and in

Fig. 8 a perspective view of a first member according to one embodiment.

DETAILED DESCRIPTION

Referring to Figs.1-3, the main components of an embodiment of a key box are now described. The key box comprises a first member 1 and a second member 2. To- gether the first and second members 1 , 2 define a secure space. The second mem- ber 2 has peripheral side walls projecting in an axial direction from a front wall of the second member 2 towards the first member 1. The second member of the embodi- ment shown here has four side walls arranged to define an essentially rectangular contour as seen in a lateral plane perpendicular to the axial direction. As best seen in Figs.2 and 3, the first member 1 is adapted for mounting to a flat surface of a support structure, such as a wall (not shown). The first member 1 is plate essentially shaped and arranged in a lateral plane perpendicular to the axial direction. The first member 1 has mounting holes 10 for fixation to the support structure. The first and second members 1 , 2 are connected to each other via a hinge 21 arranged along- side one of the side walls parallel and close to the rear surface of the key box. The first and second members 1 , 2 are thus moveable with respect to each other in an articulated movement around the pivot axis defined by the hinge 21 between a CLOSED position as seen in Figs.1 and 2, and an OPEN position as seen in Fig.3. The secure space is accessible when the key box is open, i.e. when the first and second members 1 , 2 are in the OPEN position. Access to the secure space is pre- vented when the key box is closed, i.e. when the first and second members 1 , 2 are in the CLOSED position.

In the embodiment shown, the first member 1 is configured as a base plate. A lock- ing system is fixed to the first member on an inwardly facing surface thereof. The locking system includes a locking mechanism 3, with a locking disk that is operable to engage the second member 2 so as to bring about a locking effect and to disen- gage the second member again for unlocking. The locking mechanism 3 is arranged inside a housing 4, together with any drive, control, and communication electronics as well as a battery power supply. Most preferably, the locking mechanism is oper- ated using a mobile device providing authentication to the control electronics of the locking system through a wireless connection, most preferably a short-range non- line-of-sight wireless connection, such as a Bluetooth connection. Suitable control electronics for use in a key box is e.g. referred to in the international patent applica- tion WO 2015/107006 A1.

The housing 4 carries a compartment 5 for receiving small items, such as keys, ac- cess cards, access tokens, credit cards, or similarly sized valuable items therein. The locking mechanism and the compartment are thus arranged inside the secure space defined by the first and second members 1 ,2, and are therefore both protect- ed from attacks or unauthorized access when the key box is closed and locked. Ad- vantageously, the compartment 5 is detachable to simplify the placing the items therein and/or retrieving the items from the compartment.

The second member 2 has on the inside of the side walls an inwardly projecting nose extending in a lateral plane along at least a major portion of the three side walls not comprising the hinge 21. The inwardly projecting nose forms a flange 19, which provides engagement points for a plurality of projecting cams 18 of the locking mechanism 3 to provide a locking effect when the key box is closed.

In the CLOSED position, a circumferential edge 22 of the second member at the distal end opposite to the top wall is essentially flush with a lateral plane defined by the first member as best seen in Fig.2. The second member thus forms a lid with side walls enclosing the first member as seen in lateral directions, when the key box is in the CLOSED position. Any gap at the contact interface between the first and second members thus faces towards a support surface to which the key box is mounted, which makes it difficult for an attacker to access any such gap for inserting a wedging tool to pry open the key box.

Fig. 4 shows a further front perspective view of an embodiment of a rectangular key box formed by a first member 1 and a second member 2 hinged together at a short edge thereof by means of a hinge 21. The hinge 21 allows for a pivotal movement of the second member 2 with respect to the first member 1 around a hinge axle 20. For the assembly of a hinged key box, the hinge axle 20 is advantageously inserted through a bore along the pivot axis penetrating at least from one side through the outer surface of the second member. Such a visible axle placement hole may be vulnerable to attacks. Advantageously according to some embodiments, the hinge axle 20 is therefore recessed with respect to the surface of the second member as indicated in Fig.4, and a remaining hole is concealed. For example, the axle mount- ing hole is plugged with a weld material, such as a hardfacing weld material, grinded and coated so as to conceal the axle mounting hole.

As furthermore seen in Fig.4, the key box is advantageously provided with an emer- gency jumper connector 9 for supplying electrical power to the key box drive, con- trol, and communication electronics from an external power source. According to some embodiments, the emergency jumper connector 9 may even provide a secure data interface for wired transmission of authentication data communication to the control electronics, thereby allowing the operation of the locking mechanism 3 through the emergency jumper connector. Turning now to Figs.5 and 6, the multiple point locking action of the key box by means of a simple, short travelled rotational movement of a single element is ex- plained. The single element is a locking plate 8 which is rotatable around a rotation axis R. Figs.5 and 6 show a cross-sectional detail of the key box as seen in a later- ally oriented cut-plane, i.e. a cut-plane that is arranged perpendicular to the rotation axis R. The rotation axis R thus points perpendicular out of the drawing plane. The rotation axis R defines the axial direction. The first member 1 as seen in the lateral cut-plane is enclosed by the side walls of the second member 2. The side wall with the hinge 21 is not shown in Figs.5 and 6, but would be located in a direction to- wards the bottom of the Figs.5 and 6. The side walls of the second member 2 are provided with an inwardly projecting nose forming a flange 19 extending along the side walls in a lateral plane perpendicular to the axial direction. The locking pate 8 has a plurality of (three) cams 18a-c pointing in (three) different directions away from the rotation axis R, and towards the side walls of the second member 2. The locking action is brought about by rotating the locking plate 8 into a position, where the cams 18a, 18b, 18c engage the flange 19 at corresponding engagement points 19a, 19b, 19c, respectively. This is the LOCK position as seen in Fig.5. Rotation of the locking plate 8 is achieved by coupling the locking plate 8 via a drive shaft 13 to a drive mechanism. By rotating the locking plate 8 into the LOCK positions all cams 18a-c simultaneously engage the flange 19 at their corresponding engagement points 19a-c, thereby bringing about a strong locking effect in a simple manner re- quiring only little power for the motorized operation of the locking mechanism. The construction of the embodiment shown in Figs.5 and 6 is particularly sturdy and compact, since the cams 18a-c engage the second member 2 very close to the side walls, and further since for each of the cams 18a, 18b, 18c a connecting line from the rotation axis R to the corresponding engagement points 19a, 19b, 19c is per- pendicular to the corresponding side wall as seen in a projection onto a lateral plane. Furthermore, the construction is particularly sturdy, since the locking forces brought about by the engagement of the cams 18a-c with the flange 19 are evenly distributed amongst the three engagement-points 19a-c, since the cam engagement radii are the same for all of the cams 18a-c. The locking action is lifted by rotating the locking plate 8 into a position, where the cams 18a, 18b, 18c point away from the corresponding engagement points 19a, 19b, 19c, thereby releasing the flange 19 and allowing the second member 2 to move freely with respect to the first mem- ber 1 , about the hinge 21. This is the UNLOCK position as seen in Fig.6. More par- ticularly, the locking plate 8 is rotated such that the cams 18a-c point towards the corners formed between adjoining side walls. A guide cut-out 23 on the locking plate 8 interacts with a stopper 17 fixed to the first member 1 to provide limit stops for the angular travel of the locking disk 8, wherein end stops define the LOCK and UN- LOCK positions seen in Figs.5 and 6, respectively.

Fig.7 shows an electric locking mechanism including a locking plate 8 with cams 18, wherein the locking plate 8 is coupled by means of a drive shaft 13 (best seen in Figs.5 and 6) to the output shaft of a gear box 7, which is driven by an electrical mo- tor coupled to the input of the gear box, preferably via a worm drive.

Fig.8 shows a perspective view of the side of the first member 1 facing towards the secure space, i.e. when the key box is assembled, towards the locking mechanism 3. The locking plate 8 is attached and secured to the first member 1 by means of a sliding bearing with a bearing shaft 14 of the locking plate 8 rotating in a sliding bearing cage 16 on the first member 1. The bearing shaft 14 is concentric with the rotation axis R of the locking plate. Easy assembly is facilitated by using a bayonet- type interlock between the locking plate 8 and the first member 1. The bayonet-type interlock is achieved between lips 15 on a bearing shaft 14 of the locking plate 8 on the one side, and cut-outs and protrusions of the bearing cage 16 on the other side, in cooperation with the stopper 17. The cut-outs are for the insertion of the lips 15 of the bearing shaft 14 into the bearing cage 16 for assembly. The stopper 17 is insert- ed after the bearing shaft 14 of the locking plate 8 has been placed in the bearing cage 16 of the first member 1. Once assembled, the protrusions are for keeping the lips 15 in place in the bearing cage 16 under operation. The cut-outs and protrusions of the bearing cage 16 are therefore oriented such with respect to the lips 15 of the locking plate 8 that in working angular positions as limited by the stopper 17, the protrusions retain the lips 15 of the locking plate 8 in the bearing cage 16. LIST OF REFERENCE NUMBERS

1 - first member

2 - second member

3 - locking mechanism

4 - housing

5 - compartment

6 - motor

7 - gear box

8 - locking plate

9 - emergency jumper connector

10 - mounting hole

13 - drive shaft

14 - bearing shaft

15 - lip

16 - bearing cage

17 - stopper

18 - cam

18a, 18b, 18c - cams

19 - flange

19a, 19b, 19c - engagement points

20 - hinge axle

21 - hinge

22 - edge

23 - guide cut-out

R - rotation axis