WO2019210988A1

WO2019210988A1 - Coupling arrangement for selectively engaging and disengaging a first and a second shaft

Info

Publication number: WO2019210988A1
Application number: PCT/EP2018/084587
Authority: WO
Inventors: Per Micael Beronius
Original assignee: Axema Access Control Ab
Priority date: 2018-05-03
Filing date: 2018-12-12
Publication date: 2019-11-07
Also published as: EP3788220A1; EP3788220C0; SE1800084A1; EP3788220B1; SE542521C2

Abstract

The present inventive concept relates to a coupling arrangement for selectively engaging and disengaging a first and a second shaft extending coaxially along an axis A. The coupling arrangement comprises: a first coupling member, and a second coupling member comprising a sleeve shaped, wherein the first coupling member is configured to be rotatably housed within the sleeve shaped element; a selecting element; and at least one locking element; wherein the coupling arrangement is configured to assume an engaged configuration, and a disengaged configuration.

Description

COUPLING ARRANGEMENT FOR SELECTIVELY ENGAGING AND

DISENGAGING A FIRST AND A SECOND SHAFT

Technical field

The inventive concept described herein generally relates to coupling arrangements, and in particular to a coupling arrangement for selectively engaging and disengaging a first and a second shaft.

Background

Coupling mechanisms for selectively coupling shafts are known in the art. Such coupling mechanisms may be used to provide access to closed and/or secured areas or rooms via e.g. locks in doors, windows, containers, or the like. Some coupling mechanisms physically prevent e.g. a handle of a door to be turned while in the locked state. These are often possible to force open simply by applying enough force to break the mechanism preventing rotation.

When designing a coupling mechanism, care must be taken to achieve a compact mechanism possible to be integrated into the handle or lock cylinder of e.g. a door. The mechanism must also be able to transmit large torques reliably, while utilizing a small amount of energy to operate the coupling mechanism considering power is supplied mostly by batteries.

There is therefore a need for improved coupling mechanisms. Summary of the invention

It is an object of the present inventive concept to mitigate, alleviate or eliminate one or more of the above-identified deficiencies in the art and

disadvantages singly or in combination.

According to a first aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a coupling arrangement for selectively engaging and disengaging a first and a second shaft extending coaxially along an axis A, wherein the coupling arrangement comprises: a first coupling member configured to be secured to the first shaft, wherein the first coupling member has a circular cross-sectional shape transverse to the axis A and an outer surface comprising at least one groove; a second coupling member configured to be secured to the second shaft, wherein the second coupling member comprises a sleeve shaped element coaxial with axis A and at least one through hole arranged in the sleeve shaped element radially to the axis A, wherein the first coupling member is configured to be rotatably housed within the sleeve shaped element; a selecting element; and at least one locking element; wherein the coupling arrangement is configured to assume an engaged configuration, in which the selecting element is arranged in an engaged position such that the at least one locking element is held in place by the selecting element in the at least one through-hole and is in contact with an inner surface of the at least one through-hole and the at least one groove;

wherein the coupling arrangement is configured to assume a disengaged

configuration, in which the selecting element is arranged in a disengaged position such that the at least one locking element is allowed to move out of the at least one groove.

The coupling arrangement according to the inventive concept provides for that the first and second shaft may be disengaged such that no force is transmitted from the first axis to the second axis. Further, the disengaged configuration allows the first shaft and the first coupling member to rotate freely with respect to the second coupling member and the second shaft. Hence, the coupling arrangement is less susceptible to break through attempts or failure by merely applying high torque via the first shaft.

An outer radius of the first coupling member may correspond to an inner radius of the sleeve shaped element, thus allowing the first coupling member to be rotatably housed within the sleeve shaped element.

The at least one groove may extend parallel to the axis A. In particular, the at least one groove may be configured to be in contact with two or more locking elements. Several different arrangements of the at least one groove are envisioned: for example, the first coupling member may comprise one groove corresponding to each locking element comprised in the coupling arrangement, and/or the at least one groove may be extended such that one or more locking elements fit in the at least one groove side by side along the axis A. Further, the at least one groove may be open ended, preferably at an end proximal to the second shaft. Hereby, disassembly of the coupling arrangement may be facilitated, e.g. the first coupling member may be moved in a direction parallel to the axis A even if the selecting element is in the engaged position, i.e. even if the locking elements are in contact with the at least one groove.

The selecting element may comprise at least one magnetic element arranged on the selecting element. The coupling arrangement may further comprise a magnetic sensor arrangement configured to determine a position of the selecting element relative the second coupling member based on the at least one magnetic element. The magnetic sensor arrangement may be arranged on a circuit board positioned in proximity of the coupling arrangement. The advantages of determining the position of the selecting element relative the second coupling member will be discussed further below in the present disclosure.

The at least one groove may be arranged to align with the at least one through hole when the coupling arrangement is in the engaged configuration.

Hereby, the at least one locking element may be in contact with the inner surface of the at least one through-hole and with the at least one groove. The at least one locking element may be spherically shaped. Hereby, the at least one locking element may withstand high loads e.g. when the coupling arrangement is in the engaged configuration and torque is applied to the first shaft. A spherically shaped element may also provide for that forces are evenly distributed over the at least one locking element. Further, a spherically shaped locking element may be easily moved into and out of the at least one groove.

The at least one groove may comprise inclined side walls configured to bias the at least one locking element to move out of the at least one groove. Hereby, the at least one locking element may easily move out of the at least one groove, assisted by gravity, when the selecting element is in the disengaged position. Further, the inclined side walls may create a better force transmission from the first shaft to the second shaft via the first and second coupling member. The inclined side walls may be inclined with respect to a radial direction. The inclined side walls may be inclined by at least 10 degrees, such as by at least 20 degrees, with respect to the radial direction. The inclined side walls may be inclined with respect to a bottom surface of the at least one groove. In particular, the inclined side walls may be inclined by more than 90 degrees, such as between 100 and 110 degrees with respect to the bottom surface of the at least one groove.

The coupling arrangement may further comprise a driving unit configured to move the selecting element between the engaged position and the disengaged position. The driving unit may be e.g. a step motor, and/or a mechanical

arrangement operated by a user.

The selecting element may be configured to rotatably encase an outer surface of the second coupling member about the axis A, wherein the selecting element comprises at least one recess defining a cavity between the selecting element and the outer surface of the second coupling member, wherein the cavity is arranged to at least partly receive the at least one locking element when the selecting element is in the disengaged position. In other words, the at least one locking element may be at least partly arranged within said cavity when the selecting element is in the disengaged position. Hereby, the at least one locking element may be held at least partly within the at least one through-hole, while not being in contact with the at least one groove, thus allowing the first coupling member to rotate freely about the axis A with respect to the second coupling member.

The first coupling member, second coupling member, and selecting element may be configured such that when the coupling arrangement is in the engaged configuration, the first and second coupling member may rotate freely with respect to the selecting element. In particular, the selecting element may be configured to be held in place, e.g. by the driving unit, when the first and/or second coupling member is rotated. However, the range of motion about the axis A may be defined by an extension of the cavity around a circumference of the first coupling member. This will be further discussed in the detailed description of the present disclosure.

The at least one cavity may extend within a sector of the circular

cross-sectional shape of the first coupling member. The sector may have an angle being equal to or less than 50 degrees, such as equal to or less than 45 degrees. Hereby, the first and second coupling member may be rotated a maximum of e.g. 50 or 45 degrees with respect to the selecting member. Hereby, the coupling

arrangement may allow e.g. a handle being connected to either of the first and second shaft to be rotated a maximum of e.g. 50 or 45 degrees.

The selecting element may comprise gear teeth configured to engage with a force feed element of the driving unit.

The recess may comprise inclined side walls configured to facilitate movement of the at least one locking element into contact with the at least one groove upon rotating the selecting element about the axis A to the engaged position. The first coupling member may comprise at least two grooves arranged radially symmetrically about the axis A, wherein the second coupling member comprises at least two through-holes arranged radially symmetrically about the axis A, and wherein the coupling arrangement further comprises at least two locking elements. Hereby, forces may be distributed over several locking elements, grooves, and through-holes. Further, forces may be more symmetrically applied about the axis A.

Either of the first and second shaft may be connected to a handle and the other to a locking case. Hereby, a simple coupling arrangement for managing access via a door may be provided.

According to a second aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by use of the coupling arrangement according to the first aspect to connect a handle to a locking case.

A feature described in relation to one aspect may also be incorporated in other aspects, and the advantage of the feature is applicable to all aspects in which it is incorporated.

Other objectives, features and advantages of the present inventive concept will appear from the following detailed disclosure, from the attached claims as well as from the drawings.

Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. Further, the use of terms "first", "second", and "third", and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. All references to "a/an/the [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of said element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

Brief description of the drawings

The above, as well as additional objects, features and advantages of the present inventive concept, will be better understood through the following illustrative and non-limiting detailed description of different embodiments of the present inventive concept, with reference to the appended drawings, wherein: FIG. 1 illustrates, in an exploded view, a coupling arrangement;

FIG. 2 illustrates a coupling arrangement;

FIG. 3 illustrates a coupling arrangement in a cross-sectional side view;

FIG. 4a - 4c illustrates a coupling arrangement in different configurations in a transverse cross-sectional view;

FIG. 5a - 5b illustrates a coupling arrangement, magnetic elements and a magnetic sensor arrangement in a transverse cross-sectional view;

FIG. 6a - 6e illustrates a coupling arrangement, magnetic elements and a magnetic sensor arrangement in a transverse cross-sectional view. The figures are not necessarily to scale, and generally only show parts that are necessary in order to elucidate the inventive concept, wherein other parts may be omitted or merely suggested.

Detailed description

FIG. 1 illustrates, in an exploded view, a coupling arrangement 100 for selectively engaging and disengaging a first and a second shaft 102, 104 extending coaxially along an axis A. The coupling arrangement 100 comprises a first coupling member 106 configured to be secured to the first shaft 102, wherein the first coupling member 106 has a circular cross-sectional shape transverse to the axis A and an outer surface 108 comprising at least one groove. The outer surface 108 here comprises a first groove 109 and a second groove 1 10 being radially symmetrically arranged. The two grooves 109, 1 10 here extend in a direction parallel to the axis A, and are open ended. The coupling member 106 also comprises a shaft cavity 11 1 configured to receive the first shaft 102 such that the first coupling member 106 may be secured to the first shaft 102. The coupling arrangement 100 further comprises a second coupling member

112 configured to be secured to the second shaft 104, wherein the second coupling member 112 comprises a sleeve shaped element 114 coaxial with axis A and four through holes arranged in the sleeve shaped element 114 radially to the axis A. It may be noted that only a first and a second through-hole 116, 1 17 is visible; a third and a fourth through-hole is arranged opposite the first and second through-hole 1 16, 1 17 in the sleeve shaped element 1 14. The first coupling member 106 is configured to be rotatably housed within the sleeve shaped element 114. The coupling arrangement 100 further comprises a selecting element 118, and four locking elements corresponding to the four through-holes. It may be noted that only a first and a second locking element 120, 122 is visible; a third and a fourth locking element may be incorporated into the coupling arrangement 100. The selecting element 1 18 is here annular, and comprises gear teeth 124. The selecting element 118 may be configured to rotatably encase an outer surface 126 of the second coupling member 1 12 about the axis A. The selecting element 1 18 comprises a first recess 128 defining a first cavity 130 between the selecting element 118 and the outer surface 126 of the second coupling member 1 12, and a second recess (not shown) defining a second cavity (not shown) between the selecting element 118 and the outer surface 126 of the second coupling member 112.

The coupling arrangement 100 is configured to assume an engaged configuration, in which the selecting element 118 is arranged in an engaged position such that the first and second locking element 120, 122 are held in place by the selecting element 118 in the first and second through-holes 116,117 respectively, and are in contact with an inner surface 132, 134 of the first and second through- holes 116, 1 17 respectively and first groove 109.

The coupling arrangement 100 is also configured to assume a disengaged configuration, in which the selecting element 118 is arranged in a disengaged position such that the first and second locking element 120, 122 are allowed to move out of the first groove 109. The engaged configuration and the disengaged configuration will be further discussed in conjunction with FIGS. 4a - 4c.

As is readily understood by the person skilled in the art, the general function described below may apply to any number of cavities and corresponding locking elements. The second cavity is arranged to at least partly receive the first locking element 120 and the second locking element 122 when the selecting element 118 is in the disengaged position. In other words, the first locking element 120 and the second locking element 122 may be at least partly arranged within said cavity when the selecting element 1 18 is in the disengaged position.

Still referring to FIG. 1 , magnetic elements 1 19 arranged on the selecting element 118 are visible. The number of magnetic elements and their locations will be discussed further in conjunction with FIGS. 5a - 5b and 6a - 6e.

Referring now to FIG. 2, an assembled coupling arrangement 100 is illustrated, being connected to a first and a second shaft 102, 104. Here, the first coupling member is rotatably housed within the sleeve shaped element 1 14 of the second coupling member 112, and the first coupling member is therefore concealed in the illustrated figure.

Referring now to FIG. 3, a cross-sectional side view of a coupling

arrangement 100 is illustrated. Here, it can more clearly be seen that the second coupling member 112 comprises four through-holes arranged in the sleeve shaped element 114; the first, second, third and fourth through-holes 1 16, 117, 136, 137 are arranged pairwise, the first and second through-hole 1 16, 1 17 on one side of the sleeve shaped element 114, and the third and fourth through-hole 136, 137 on an opposite side of the sleeve shaped element. Further, four locking elements are also clearly illustrated; the first and second locking element 120, 122 being in contact with the first groove 109, and the third and fourth locking element 140, 142 being in contact with the second groove 1 10.

The coupling arrangement 100 is here in an engaged configuration; the locking elements 120, 122, 140, 142 are in contact with the first and second grooves 109, 1 10, and the locking elements 120, 122, 140, 142 are held in place by the selecting element 1 18 in the respective through-holes 1 16, 1 17, 136, 137. In other words, the locking elements 120, 122, 140, 142 are forced into the first and second grooves 109, 1 10. The first and second shaft 102, 104 can also be seen in the illustrated figure.

Referring now to FIGS. 4a - 4c, a coupling arrangement 100 is illustrated in different configurations in a transverse cross-sectional view.

In FIG. 4a, the coupling arrangement 100 is in a disengaged configuration, in which the selecting element 118 is arranged in a disengaged position. In particular, the selecting element 118 may be arranged in a disengaged position with respect to the second coupling member 112. The first and third locking element 120, 140 are here partly arranged within the second and first cavities 138, 130 respectively, and the first and third locking elements 120, 140 are not in contact with the first and second grooves 109, 110 respectively. In the disengaged configuration, the first coupling member 106 is allowed to rotate freely with respect to the second coupling member 112, and thus the first and second shaft (not shown) are not engaged.

Referring now to FIG. 4b, the selecting element 118 has been rotated counter-clockwise as seen from this view with respect to FIG. 4a, and an inclined side wall 146, 144 of the respective second and first cavity 138, 130 is abutting respective locking elements 120, 140. The inclined side walls 146, 144 may facilitate movement of the locking elements 120, 140 into the contact with the first and second grooves 109, 1 10 respectively.

Referring now to FIG. 4c, the selecting element 118 has been further rotated counter-clockwise as seen from this view with respect to FIGS. 4a and 4b. The selecting element 1 18 is now in an engaged position, and the coupling arrangement 100 is in an engaged configuration. The first locking element 120 is held in place in the through-hole 1 16 by an inner surface 148 of the selecting element, and is in contact with an inner surface (not shown) of the through hole 1 16 and the first groove 109. Similarly, the second locking element 140 is held in place in the through- hole 136 by an inner surface 150 of the selecting element, and is in contact with an inner surface 152 of the through hole (not shown) and the second groove 110.

Referring now to FIG. 5a, a coupling arrangement 100 is illustrated in a cross- sectional view transverse to the axis A. The location of magnetic elements arranged on the selecting element 118 are shown in the rightmost part of the figure, and the locking elements 120, 140 and position of the selecting element 118 are shown in the leftmost part of the figure. The selecting element 118 is here in a disengaged position, where the locking elements 120, 140 are at least partly arranged within the second and first cavity 138, 130 respectively, and the locking elements 120, 140 are not in contact with the first and second groove 109, 1 10 respectively. It may be noted that the locking elements 120, 140 are not shown in the rightmost part of the figure since this cross-sectional view is taken at a different location along the axis A compared to the leftmost part of the figure.

Here, the selecting element 118 comprises a first magnetic element 152 and a second magnetic element 154, arranged radially symmetrically about the axis A.

Accordingly, the first and second magnetic elements 152, 154 are separated by an angle of 180 degrees. A magnetic sensor arrangement configured to sense the magnetic elements 152, 154 may be arranged and configured to sense magnetic elements at a first location 156 and a second location 158 separated by an angle of 90 degrees. Preferably, the magnetic sensor arrangement is arranged such that the first magnetic element 152 is located at either the first or second location 156, 158 when the selecting element 118 is in the disengaged position. This will provide for that when the selecting element is moved to the engaged position, in this case a rotation clockwise or counter-clockwise of 90 degrees, either the first magnetic element 152 will be located at the other of either the first or second location 156, 158, or the second magnetic element 158 will be located at the other of either the first or second location 156, 158. Hereby, it is possible to determine, via the magnetic elements and the magnetic sensor, whether the selecting element 118 is in the engaged or disengaged position, and thus whether the coupling arrangement 100 is in the engaged or disengaged configuration. FIG. 5b illustrates the coupling arrangement 100 in the engaged configuration, however it should be noted that the magnetic sensor arrangement is not shown in this figure.

Referring now to FIGS. 6a - 6e, a coupling arrangement and magnetic sensors are illustrated in a cross-sectional view transverse to the axis A. The location of magnetic elements on the selecting element 1 18 is shown in the rightmost part of the figures, and the locking elements and position of the selecting element 118 are shown in the leftmost part of the figures. In order to facilitate reference to the cross- sectional view, a coordinate system will be used, wherein an X-axis extends through the through-holes of the second coupling member, and a Y-axis extends

perpendicular to the X-axis. Reference to angles will be made with respect to the X- axis unless stated otherwise.

Referring first to FIG. 6a, a coupling arrangement 100 is illustrated in a disengaged configuration, wherein the selecting element 118 is in a neutral position. The neutral position is a position wherein the through-hole of sleeve shaped element in the second coupling member is centered with respect to the first and second recesses 128, 139, defining the first and second cavities 130, 138 respectively. In other words, in the neutral position the selecting element 1 18 is centered about the X-axis.

In the rightmost part of FIG. 6a, it can be seen that four magnetic elements 160, 162, 164, 166 are arranged symmetrically about the Y-axis. A first magnetic element 160 is arranged at a biased angle, here being 67,5 degrees, and a second magnetic element is arranged at a switching angle, here being 337,5. Accordingly, the third and fourth magnetic elements 164, 166 are mirrored, and are thus arranged at 112,5 degrees and 202,5 degrees respectively.

The selecting element 1 18 here comprises four magnetic sensors 168, 170, 172, 174 arranged at 0 degrees, 90 degrees, 180 degrees and 270 degrees respectively. It should be noted that the magnetic sensors may not be arranged on the selecting element 118, but on an element being separate to the selecting element 118, e.g. a printed circuit board arranged in connection to the coupling arrangement 100, or a printed circuit board comprised in the coupling arrangement 100

The selecting element 118 may be turned counter-clockwise as will be seen in FIGS. 6b and 6c, and thus allow clockwise rotation of the first shaft as seen from this view. Similarly, the selecting element 1 18 may be turned clockwise as will be seen in FIGS. 6d and 6e, and thus allow counter-clockwise rotation of the first shaft as seen from this view.

Referring now to FIG. 6b, the selecting element 1 18 has been set to a pre-set angle of 22,5 degrees. The selecting element 1 18 is thus biased for a

counter-clockwise rotation of the selecting element 1 18. It should be noted that the selecting element 1 18 is still in a disengaged position, and the coupling arrangement 100 is thus in a disengaged configuration. In this first biased position of the selecting element 118, the first magnetic element 160, now being at 90 degrees (67,5 + 22,5), lines up with the second magnetic sensor 170, and the second magnetic element 162, now being at 0 degrees (-22,5 + 22,5), lines up with the first magnetic sensor 168. Thus, the fist biased position of the selecting element 1 18 may be detected by the magnetic sensor arrangement, and in particular the disengaged position of the selecting element 1 18 may be detected by the magnetic sensor arrangement.

The first biased position of the selecting element 1 18 is advantageous in that it decreases the rotational movement required of the selecting element 1 18 in order to move from a disengaged position to an engaged position.

Referring now to FIG. 6c, the selecting element 1 18 has been rotated 45 degrees counter-clockwise as compared to FIG. 6b, for a total rotation of 67,5 degrees as compared to the neutral position of the selecting arrangement 118. The selecting element 118 is in an engaged position, and the coupling arrangement 100 is thus in an engaged configuration. In this engaged position of the selecting element 1 18, the third magnetic element 164, now being at 180 degrees (112,5 + 22,5 + 45), lines up with the third magnetic sensor 172, and the fourth magnetic element 166, now being at 270 degrees (202,5 + 22,5 + 45), lines up with the fourth magnetic sensor 174. Thus, the engaged position of the selecting element 118 may be detected by the magnetic sensor arrangement, and in particular the disengaged position of the selecting element 118 may be detected by the magnetic sensor arrangement. The illustrated engaged position of the selecting element 118 allows for a rotation of the first coupling member or the second coupling member of about 67,5 degrees clockwise as seen from this view, before e.g. the first locking element 120 reaches the first cavity 130 of the selecting element 118 and the coupling

arrangement is again in a disengaged configuration. The person skilled in the art appreciates that the size of the recesses and cavities of the selecting element may be adjusted in order to achieve a given range of motion of the first coupling member or the second coupling member while staying in the engaged configuration.

Referring now to FIG. 6d, the selecting element 118 has been set to a pre-set angle of -22,5 degrees. The selecting element 1 18 is thus biased for a clockwise rotation of the selecting element 1 18. It should be noted that the selecting element 1 18 is still in a disengaged position, and the coupling arrangement 100 is thus in a disengaged configuration. In this second biased position of the selecting element 1 18, the third magnetic element 164, now being at 90 degrees (1 12,5 + (-22,5)), lines up with the second magnetic sensor 170, and the fourth magnetic element 166, now being at 180 degrees (202,5 + (-22,5)), lines up with the third magnetic sensor 172. Thus, the second biased position of the selecting element 118 may be detected by the magnetic sensor arrangement, and in particular the disengaged position of the selecting element 1 18 may be detected by the magnetic sensor arrangement.

The second biased position of the selecting element 1 18 is advantageous in that it decreases the rotational movement required of the selecting element 1 18 in order to move from a disengaged position to an engaged position.

Referring now to FIG. 6e, the selecting element 118 has been rotated 45 degrees clockwise as compared to FIG. 6d, for a total rotation of 67,5 degrees clockwise as compared to the neutral position of the selecting arrangement 118. The selecting element 1 18 is in an engaged position, and the coupling arrangement 100 is thus in an engaged configuration. In this engaged position of the selecting element 1 18, the first magnetic element 160, now being at 0 degrees (67,5 + (-22,5) + (-45)), lines up with the first magnetic sensor 168, and the second magnetic element 162, now being at 270 degrees (337,5 + (-22,5) + (-45)), lines up with the fourth magnetic sensor 174. Thus, the engaged position of the selecting element 1 18 may be detected by the magnetic sensor arrangement, and in particular the disengaged position of the selecting element 118 may be detected by the magnetic sensor arrangement. The illustrated engaged position of the selecting element 118 allows for a rotation of the first coupling member or the second coupling member of about 67,5 degrees counter-clockwise as seen from this view, before e.g. the first locking element 120 reaches the first cavity 130 of the selecting element 1 18 and the coupling arrangement is again in a disengaged configuration. The person skilled in the art appreciates that the size of the recesses and cavities of the selecting element may be adjusted in order to achieve a given range of motion of the first coupling member or the second coupling member while staying in the engaged configuration.

The inventive concept has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended patent claims.

Claims

1. A coupling arrangement for selectively engaging and disengaging a first and a second shaft extending coaxially along an axis A, wherein the coupling arrangement comprises:

a first coupling member configured to be secured to the first shaft, wherein the first coupling member has a circular cross-sectional shape transverse to the axis A and an outer surface comprising at least one groove;

a second coupling member configured to be secured to the second shaft, wherein the second coupling member comprises a sleeve shaped element coaxial with axis A and at least one through hole arranged in the sleeve shaped element radially to the axis A, wherein the first coupling member is configured to be rotatably housed within the sleeve shaped element;

a selecting element; and

at least one locking element;

wherein the coupling arrangement is configured to assume an engaged configuration, in which the selecting element is arranged in an engaged position such that the at least one locking element is held in place by the selecting element in the at least one through-hole and is in contact with an inner surface of the at least one through-hole and the at least one groove; and

wherein the coupling arrangement is configured to assume a disengaged configuration, in which the selecting element is arranged in a disengaged position such that the at least one locking element is allowed to move out of the at least one groove.

2. The coupling arrangement according to claim 1 , wherein the at least one groove extends parallel to the axis A.

3. The coupling arrangement according to any one of the preceding claims, wherein the selecting element comprises at least one magnetic element arranged on the selecting element, and wherein the coupling arrangement further comprises a magnetic sensor arrangement configured to determine a position of the selecting element relative the second coupling member based on the at least one magnetic element.

4. The coupling arrangement according to any one of the preceding claims, wherein the at least one groove is arranged to align with the at least one

through-hole when the coupling arrangement is in the engaged configuration.

5. The coupling arrangement according to any one of the preceding claims, wherein the at least one locking element is spherically shaped.

6. The coupling arrangement according to any one of the preceding claims, wherein the at least one groove comprises inclined side walls configured to bias the at least one locking element to move out of the at least one groove.

7. The coupling arrangement any one of the preceding claims, further comprising a driving unit configured to move the selecting element between the engaged position and the disengaged position.

8. The coupling arrangement according to any one of the preceding claims, wherein the selecting element is configured to rotatably encase an outer surface of the second coupling member about the axis A, wherein the selecting element comprises a recess defining a cavity between the selecting element and the outer surface of the second coupling member, wherein the cavity is arranged to at least partly receive the at least one locking element when the selecting element is in the disengaged position.

9. The coupling arrangement according to claim 8, wherein the recess comprises inclined side walls configured to facilitate movement of the at least one locking element into contact with the at least one groove upon rotating the selecting element about the axis A to the engaged position.

10. The coupling arrangement according to any one of the preceding claims, wherein the first coupling member comprises at least two grooves arranged radially symmetrically about the axis A, wherein the second coupling member comprises at least two through-holes arranged radially symmetrically about the axis A, and wherein the coupling arrangement further comprises at least two locking elements.

1 1. The coupling arrangement according to any one of the preceding claims, wherein either of the first and second shaft is connected to a handle and the other to a locking case.

12. Use of the coupling arrangement according to any one of claims 1 to 11 to connect a handle to a locking case.