SYSTEM Technical Field

The present disclosure generally relates to arrangements for controlling movements of an access member. In particular, an arrangement comprising a magnet for controlling movements of an access member relative to a frame, an access member for moving relative to a frame, a frame for an access member, and an access member system, are provided.

Background

Some conventional door closers comprise a spring and a hydraulic cylinder containing oil. The spring may be increasingly compressed (or otherwise deformed) during opening of the door leaf. The hydraulic cylinder may provide a damping force proportional to the speed of the door leaf. Such conventional door closers often have unsatisfactory reliability, for example due to temperature changes and wear. Furthermore, such conventional door closers often have a mechanically complex design, for example including complex cam profiles to control a closing force. US 4973894 A discloses a door closer comprising a force transmission shaft turning in accordance with the movement of a door, a spring element operationally connected with the force transmission shaft so that opening of the door takes place against the force of the spring element, and a dynamic machine comprising rotor means arranged in force transmission connection with the force transmission shaft and stator means operationally connected with the rotor means. Summary

In some conventional door closers for controlling a door leaf rotatable relative to a frame, the force in the spring is lower the closer the door leaf is to the frame. However, the last closing movement, e.g. the last five degrees thereof, may require the highest closing force in order to latch the door leaf. A user also provides the strongest opening force to a rotatable door leaf in the initial opening movement, e.g. the first five degrees thereof. When the door leaf is opened more, the force from the user on the door leaf may become lower. One object of the present disclosure is to provide an arrangement for controlling movements of an access member relative to a frame, which arrangement has a less complicated design and/or operation.

A further object of the present disclosure is to provide an arrangement for controlling movements of an access member relative to a frame, which arrangement enables an effective latching of an access member to a frame.

A still further object of the present disclosure is to provide an arrangement for controlling movements of an access member relative to a frame, which arrangement has a cost effective design and/or operation.

A still further object of the present disclosure is to provide an arrangement for controlling movements of an access member relative to a frame, which arrangement has a reliable design and/or operation.

A still further object of the present disclosure is to provide an arrangement for controlling movements of an access member relative to a frame, which arrangement solves several or all of the foregoing objects in combination. A still further object of the present disclosure is to provide an access member for moving relative to a frame, which access member solves one, several or all of the foregoing objects. A still further object of the present disclosure is to provide a frame for an access member, which frame solves one, several or all of the foregoing objects.

A still further object of the present disclosure is to provide an access member system comprising a frame and an access member movable relative to the frame, which access member system solves one, several or all of the foregoing objects.

A still further object of the present disclosure is to provide a method of controlling movements of an access member relative to a frame, which method solves one, several or all of the foregoing objects.

According to one aspect, there is provided an arrangement for controlling movements of an access member relative to a frame, the arrangement comprising a base section for connection to either the access member or the frame; a fixation part for connection to the other of the access member and the frame; a connection device arranged between the base section and the fixation part, and connected to the base section and the fixation part; a closing force device configured to exert a force on the connection device to thereby force the base section and the fixation part to move towards each other in a relative closing movement; and a magnet arranged to force the base section and the fixation part towards each other by means of magnetic force.

By means of the magnet, the base section and the fixation part can be forced towards each other to latch an access member to a frame. Since the arrangement relies on a magnetic force by the magnet, the arrangement provides reliable latching also in the event of a fire.

The base section and the fixation part are arranged to move away from each other in a relative opening movement, opposite to the closing movement, for example when a user opens a door, against the force from the closing force device and against the force from the magnet. The magnet maybe a permanent magnet. The magnet maybe provided in the base section.

The closing force device may comprise a spring. Examples of such spring are a coil spring and a torsion spring. The base section may comprise a housing, a plate or other rigid support structure. The fixation part may for example be a rigid piece to which the connection device is secured. Alternatively, the fixation part may be constituted by an end of the connection device.

Throughout the present disclosure, the arrangement may for example be a door closer or a door operator. The arrangement according to the present disclosure can be installed in an access member system without needing any external power supply (e.g. outside of the base section). This enables installation at low cost and enables a cost effective arrangement.

As used herein, the base section and the fixation part are said to move towards each other in the relative closing movement also when only the base section moves towards the fixation part or when only the fixation part moves towards the base section. Correspondingly, the base section and the fixation part are said to move away from each other in the relative opening movement also when only the base section moves away from the fixation part or when only the fixation part moves away from the base section.

The closing force device may be a mechanical closing force device. That is, the closing force device may be entirely mechanical and not comprise any electric components.

The magnet maybe arranged to force the base section and the fixation part towards each other only during an end phase of the relative closing movement. For example, in case the arrangement is installed in an access member system comprising a frame and an access member rotatable relative to the frame, the magnet may force the access member towards the frame only during the last io degrees, such as only during the last 5 degrees, of the closing movement.

The force from the closing force device may increase and the magnetic force from the magnet may decrease when the base section and the fixation part move away from each other.

The arrangement may further comprise a magnetic target section, and the magnet may be arranged to magnetically force the magnetic target section to thereby force the base section and the fixation part towards each other. The magnetic target section may be of any type for being influenced by a magnetic field of the magnet. The magnetic target section may for example comprise a permanent magnet or a ferromagnetic material. The magnet may magnetically force the magnetic target section by either an attractive or a repulsive magnetic force.

The magnetic target section may have a substantially constantly, or constantly, decreasing cross-sectional area in a direction towards the magnet.

One of the magnet and the magnetic target section may be fixed with respect to the base section. The other of the magnet and the magnetic target section maybe fixed with respect to the fixation part.

The magnet maybe provided in the base section, or fixed with respect to the base section, and the magnetic target section may be provided in the fixation part, or fixed with respect to the fixation part. An attractive magnetic force maybe generated when the magnet and the magnetic target section are brought into proximity of each other. In this way, the base section and the fixation part can be forced towards each other. As an alternative, the magnet may be provided on the fixation part, or fixed with respect to the fixation part, and the magnetic target section may be provided in the base section, or fixed with respect to the base section.

The connection device may comprise a flexible elongated element configured to be tensioned to thereby force the base section and the fixation part to move towards each other in the relative closing movement. That is, the closing force device maybe configured to tension the elongated element to thereby force the base section and the fixation part to move towards each other in the relative closing movement. The elongated element may optionally comprise an elastic part such that the elastic part extends when the base section and the fixation part move away from each other to tension the elongated element to thereby force the base section and the fixation part to move towards each other in the relative closing movement. In this case, the elastic part may constitute the closing force device. The elastic part may be partly or entirely provided in the base section.

The arrangement may further comprise a braking device arranged to brake a speed of the relative closing movement. The braking device maybe a control element, such as a switch or a potentiometer, for changing an electric load on a generator. Alternatively, or in addition, the braking device may comprise a friction brake. Examples of such friction brake include a band brake and a centrifugal clutch.

The arrangement may further comprise a carrier. In this case, the elongated element may be arranged to move the carrier against a force from the closing force device. The magnetic target section may be fixed to the carrier and the magnet may be fixed to the base section. Alternatively, the magnetic target section maybe fixed to the base section and the magnet maybe fixed to the carrier. The carrier maybe arranged to move linearly with respect to the base section. The magnet may be arranged to force the carrier in a direction that tensions the elongated element by means of magnetic force.

As an alternative to the elongated element, the connection device may be an arm or a linkage. According to a further aspect, there is provided an access member for moving relative to a frame, the access member comprising an arrangement according to the present disclosure, wherein either the base section or the fixation part is connected to the access member. Throughout the present disclosure, the access member may for example be a door leaf or a window sash.

According to a further aspect, there is provided a frame for an access member, the frame comprising an arrangement according to the present disclosure, wherein either the base section or the fixation part is connected to the frame. According to a further aspect, there is provided an access member system comprising a frame, an access member movable relative to the frame, and an arrangement according to the present disclosure, wherein the base section is connected to either the access member or the frame, and wherein the fixation part is connected to the other of the access member and the frame. Thus, when the fixation part is connected to the access member, the base section is connected to the frame. When the fixation part is connected to the frame, the base section is connected to the access member.

Brief Description of the Drawings

Further details, advantages and aspects of the present disclosure will become apparent from the following description taken in conjunction with the drawings, wherein:

Fig. 1: schematically represents a front view of an access member system comprising an arrangement, a frame and an access member; Fig. 2: schematically represents a perspective view of the access member system in Fig. 1 when the access member is in an open position;

Fig. 3: schematically represents a perspective view of the access member system comprising an alternative configuration of the arrangement;

Fig. 4: schematically represents a perspective view of the access member system comprising an alternative configuration of the arrangement;

Fig. 5: schematically represents a perspective view of the access member system comprising an alternative configuration of the arrangement;

Fig. 6: schematically represents a top view of the access member system in Fig. 3 when the access member is in a closed position;

Fig. 7: schematically represents a top view of the access member system in Fig. 6 during opening of the access member;

Fig. 8: schematically represents a top view of the access member system in Figs. 6 and 7 when the access member is in an open position;

Fig. 9: schematically represents a top view of the access member system in Figs. 6-8 during closing of the access member;

Fig. 10: schematically represents a top view of the access member system in Figs. 6-9 when the access member has returned to the closed position;

Fig. 11: schematically represents a hinge comprising an opening force device;

Fig. 12: schematically represents a further example of a hinge comprising a further example of an opening force device;

Fig. 13: schematically represents a side view of a magnet and a magnetic target section;

Fig. 14: schematically represents a further side view of the magnet and the magnetic target section in Fig. 13;

Fig. 15: schematically represents a top view of an access member system comprising a further alternative of an arrangement when the access member is in an open position; and

Fig. 16: schematically represents a top view of the access member system in Fig. 15 when the access member is in a closed position.

Detailed Description In the following, an arrangement comprising a magnet for controlling movements of an access member relative to a frame, an access member for moving relative to a frame, a frame for an access member, and an access member system, will be described. The same or similar reference numerals will be used to denote the same or similar structural features.

Fig. l schematically represents a front view of a door system 10 comprising a door leaf 12 rotatable relative to a frame 14. The door system 10 and the door leaf 12 are examples of an access member system and an access member, respectively, according to the present disclosure.

The door system 10 comprises an arrangement 16. The arrangement 16 is configured to control movements of the door leaf 12 relative to the frame 14. The arrangement 16 comprises a base section 18, a fixation part 20 and a flexible wire 22 between the base section 18 and the fixation part 20. The wire 22 is one example of a flexible elongated element according to the present disclosure. The elongated element in turn is one example of a connection device according to the present disclosure. In the example in Fig. 1, the base section 18 is connected to the door leaf 12 and the fixation part 20 is connected to the frame 14. The fixation part 20 of this example is a rigid piece secured to the frame 14, e.g. by means of screws (not shown).

The door system 10 further comprises two hinges 24. By means of the hinges 24, the door leaf 12 is rotatable relative to the frame 14. In Fig. 1, the door leaf 12 is in a closed position 26. The arrangement 16 further comprises an opening spring 28. The opening spring 28 is one example of a mechanical opening force device according to the present disclosure. The opening spring 28 is configured to force the base section 18 and the fixation part 20 away from each other. The opening spring 28 is in this example integrated in the upper hinge 24. The opening spring 28 and the wire 22 are thereby arranged in parallel between the frame 14 and the door leaf 12.

Fig. 2 schematically represents a perspective view of the door system 10 in Fig. 1. In Fig. 2, the door leaf 12 is in an open position 30. As shown in Fig. 2, the base section 18 is connected to a side of the door leaf 12 facing the frame 14 when the door leaf 12 is in the open position 30. The wire 22 extends in a straight line between the base section 18 and the fixation part 20.

Fig. 3 schematically represents a perspective view of the door system 10 comprising an alternative configuration of the arrangement 16. The arrangement 16 in Fig. 3 differs from Figs. 1 and 2 in that the base section 18 is integrated into the door leaf 12.

Fig. 4 schematically represents a perspective view of the door system 10 comprising an alternative configuration of the arrangement 16. The arrangement 16 in Fig. 4 differs from Figs. 1-3 in that the base section 18 is connected to the frame 14 and the fixation part 20 is connected to the door leaf 12.

Fig. 5 schematically represents a perspective view of the door system 10 comprising an alternative configuration of the arrangement 16. The arrangement 16 in Fig. 5 differs from Fig. 4 in that the base section 18 is integrated into the frame 14.

Fig. 6 schematically represents a top view of the door system 10 in Fig. 3 when the door leaf 12 is in a closed position 26. The arrangement 16 of this example further comprises an electromagnetic generator 32, a transmission 34 and a winding pulley 36. In this example, the generator 32, the transmission 34 and the winding pulley 36 are concentrically arranged. The winding pulley 36 of this example is rotatable relative to the base section 18 about a rotation axis that constitutes the only degree of freedom between the winding pulley 36 and the base section 18.

The arrangement 16 of this example further comprises a carrier 38. The carrier 38 of this example is linearly movable in the base section 18. In this example, the linear movement of the carrier 38 relative to the base section 18 is the only degree of freedom between the carrier 38 and the base section 18.

The arrangement 16 of this example further comprises a carrier pulley 40. The carrier pulley 40 is connected to the carrier 38 and is rotatable relative to the carrier 38 about a rotation axis that constitutes the only degree of freedom between the carrier pulley 40 and the carrier 38.

The arrangement 16 of this example further comprises a base pulley 42. The base pulley 42 of this example is rotatable relative to the base section 18 about a rotation axis that constitutes the only degree of freedom between the base pulley 42 and the base section 18. The winding pulley 36 is arranged between the base pulley 42 and the carrier 38.

The arrangement 16 of this example further comprises a closing spring 44. The closing spring 44 is one example of a mechanical closing force device according to the present disclosure. The closing spring 44 is here exemplified as a coil spring. One end of the closing spring 44 is connected to the base section 18 and the other end of the closing spring 44 is connected to the carrier 38. The carrier 38 is arranged between the winding pulley 36 and the closing spring 44. The arrangement 16 of this example further comprises a guide pulley 46. The guide pulley 46 serves to guide the wire 22 during opening and closing of the door leaf 12.

The arrangement 16 of this example further comprises a fixing member 48. The fixing member 48 serves to fix the wire 22 to the base section 18. The wire 22 is wound around the winding pulley 36. The wire 22 then extends to the base pulley 42 and is wound half a turn around the base pulley 42. The wire 22 then extends to the carrier pulley 40 and is wound half a turn around the carrier pulley 40. The wire 22 then again extends to the base pulley 42 and is wound half a turn around the base pulley 42. The wire 22 then again extends to the carrier pulley 40 and is wound half a turn around the carrier pulley 40. The wire 22 then extends to the fixing member 48 by means of which an end of the wire 22 is fixed to the base section 18. The generator 32 and the winding pulley 36 are thus arranged between the fixation part 20 and the carrier pulley 40 along a path of the wire 22. In the state of the arrangement 16 in Fig. 6, the closing spring 44 pulls the carrier 38. The wire 22 is thereby tensioned.

The arrangement 16 of this example further comprises a magnet 50 and a magnetic target section 52. The magnet 50 is fixed to the base section 18. The magnetic target section 52 is fixed to the carrier 38. The magnet 50 is here exemplified as a permanent magnet. The magnetic target section 52 is here exemplified as a section comprising a ferromagnetic material. In the position of the arrangement 16 in Fig. 6, the magnet 50 attracts the magnetic target section 52 by means of a magnetic force. The magnet 50 thereby forces the carrier 38 in a direction that tensions the wire 22.

The generator 32 comprises a stator and a rotor rotatable relative to the stator. In this example, the winding pulley 36 is coupled to the rotor by means of the transmission 34 such that the rotor always rotates when the winding pulley 36 rotates. In this way, the wire 22, wound around the winding pulley 36, is arranged to drive the rotor relative to the stator by relative movement between the base section 18 and the fixation part 20.

When the winding pulley 36 rotates, the rotor rotates relative to the stator and the generator 32 generates electric energy. The electric energy maybe stored in a capacitor or a battery. Due to the transmission 34, the rotor rotates at a higher rotational speed than the rotational speed of the winding pulley 36.

The arrangement 16 further comprises a control system 54. The control system 54 is electrically powered by the generator 32. Thus, electric energy harvested by rotation of the winding pulley 36 is used to electrically power the control system 54. The generator 32 and the control system 54 are connected by means of electric conductors (not shown), for example electric cables.

The control system 54 of the specific example in Fig. 6 comprises a data processing device and a memory. A computer program is stored in the memory. The computer program comprises program code which, when executed by the data processing device causes the data processing device to perform, or command performance of, various steps as described herein.

By selectively controlling an electric load of the generator 32, the winding pulley 36 can be braked. To this end, the arrangement 16 may comprise one or more control elements, such as a switch or a potentiometer, for changing the electric load of the generator 32. Each such control element is therefore an example of a braking device 56 according to the present disclosure. The braking device 56 may alternatively be a friction brake. Such friction brake maybe entirely mechanical, e.g. a centrifugal clutch, or maybe electrically controlled by the control system 54.

In Fig. 6, the closing spring 44 is deformed and forces the carrier 38 (to the left in Fig. 6). The carrier 38 thereby tensions the wire 22. The magnet 50 attracts the magnetic target section 52 such that these two parts are brought into contact. In order to open the door leaf 12, the user therefore initially needs to overcome both the force from the magnet 50 and from the closing spring 44.

In Fig. 6, the opening spring 28 is deformed and thereby exerts a force on the door leaf 12 to open the same. However, the forces from the magnet 50 and the closing spring 44 overcome the force from the opening spring 28 in Fig. 6. Fig. 7 schematically represents a top view of the door system 10 in Fig. 6 during opening of the door leaf 12. In Fig. 7, the door leaf 12 moves away from the frame 14 in a relative opening movement 58. When the door leaf 12 moves away from the frame 14, the wire 22 is unwound from the winding pulley 36 and the winding pulley 36 is driven by the wire 22 to rotate (in the clockwise direction in Fig. 7). The rotation of the winding pulley 36 may be used by the generator 32 to harvest electric energy.

The unwinding of the wire 22 from the winding pulley 36 causes the carrier 38 to be pulled towards the winding pulley 36 by means of the wire 22. As shown in Fig. 7, this movement of the carrier 38 stretches the closing spring 44 and thereby further tensions the wire 22. Moreover, this movement of the carrier 38 has now caused the magnetic target section 52 to be distanced from the magnet 50. The magnetic force from the magnet 50 acting on the magnetic target section 52 is now very low or negligible. The opening force from the opening spring 28 reduces as the door leaf 12 moves away from the frame 14.

Fig. 8 schematically represents a top view of the door system 10 in Figs. 6 and 7 when the door leaf 12 is in an open position 30. The user now releases the door leaf 12. In the open position 30, the closing spring 44 exerts a relatively high force on the carrier 38. The carrier 38 thereby tensions the wire 22 with a relatively high force. In the open position 30, the closing force on the door leaf 12 generated by the closing spring 44 is higher than the opening force on the door leaf 12 generated by the opening spring 28.

Fig. 9 schematically represents a top view of the door system 10 in Figs. 6-8 during closing of the door leaf 12. When the user has released the door leaf 12, the closing spring 44 pulls the carrier 38. This movement of the carrier 38 causes the wire 22 to be pulled to wind around the winding pulley 36 and the door leaf 12 to move in a relative closing movement 60 towards the frame 14. The closing spring 44 thereby acts to close the door leaf 12. Also this rotation of the winding pulley 36 may be used by the generator 32 to harvest electric energy. Also the base section 18 moves towards the fixation part 20 in the closing movement 60. The opening spring 28 limits the speed of the closing movement 60.

A closing speed of the door leaf 12 can be determined based on a rotational speed of the winding pulley 36 and/or the rotor. If the closing speed becomes too high, any of the braking devices 56 may be activated to brake the winding pulley 36. In this example, the electric load on the generator 32 is controlled to provide a braking force on the winding pulley 36. When the winding pulley 36 is braked, movement of the wire 22 relative to the base section 18 is braked and the tension in the wire 22 between the winding pulley 36 and the fixation part 20 is reduced. The opening effect from the opening spring 28 will counteract the closing movement 60 to a larger extent the more this tension in the wire 22 is reduced. Also friction in the hinges 24 will counteract the closing movement 60. If for example the door leaf 12 is exposed to a sudden wind acting to close the door leaf 12, the opening spring 28 reduces the effect of such wind. Thus, when the braking device 56 is applied, a speed of the closing movement 60 of the door leaf 12 will be reduced.

In the last part of the closing movement 60, for example the last five degrees thereof, the magnetic target section 52 comes sufficiently close to the magnet 50 to be attracted by the magnet 50. In addition to the force from the closing spring 44, which decreases during the closing movement 60, the magnetic force from the magnet 50 on the magnetic target section 52 additionally pulls the carrier 38. This causes an additional pull in the wire 22 such that an additional latching force is provided to reliably close the door leaf 12. Optionally, the generator 32 can be driven as a motor during the last phase of the closing movement 60 to further increase the latching force.

Fig. 10 schematically represents a top view of the door system 10 in Figs. 6-9 when the door leaf 12 has returned to the closed position 26. The generator 32 can be driven as a motor (e.g. in the clockwise direction in Fig. 10) to open the door leaf 12. That is, when the rotor is driven in the clockwise direction in Fig. 10, the length of wire 22 between the winding pulley 36 and the fixation part 20 is increased and the opening spring 28 forces the door leaf 12 to open correspondingly.

Fig. 11 schematically represents the upper hinge 24 in Figs. 1-5. As mentioned, the opening spring 28 is integrated into the hinge 24. The opening spring 28 is arranged to force the door leaf 12 in an opening direction away from the frame 14. The opening spring 28 is thereby also arranged to force the base section 18 and the fixation part 20 away from each other. The opening spring 28 in Fig. 11 is a torsion spring.

Fig. 12 schematically represents a further example of a hinge 24 comprising a further example of an opening spring 28. The hinge 24 in Fig. 12 comprises an opening spring 28 constituted by a compression coil spring. Also the opening spring 28 in Fig. 12 is arranged to force the door leaf 12 in the opening direction away from the frame 14.

Figs. 13 and 14 schematically represent side views of the magnet 50 and the magnetic target section 52. In Fig. 13, the magnetic target section 52 is sufficiently close to the magnet 50 to be attracted by the magnet 50. This is the case during an initial phase of the opening movement 58 and during a final phase of the closing movement 60.

As shown in Fig. 13, the magnetic target section 52 has a constantly decreasing cross-sectional area in a direction towards the magnet 50. Also a body 62 housing the magnet 50 comprises a decreasing cross-sectional area in a direction towards the magnetic target section 52. In this example, the profiles of the magnet 50 and the magnetic target section 52 are flat surfaces inclined with respect to a separation direction between the magnet 50 and the magnetic target section 52. The profiles of the body 62 and of the magnetic target section 52 provide a well calibrated latching force in the final closing movement 60 of the door leaf 12. In Fig. 14, the magnetic target section 52 is brought into contact with the body 62. As shown in Fig. 14, the profiles of the body 62 and the magnetic target section 52 provide a mating interface.

Fig. 15 schematically represents a top view of an door system 10 comprising an alternative arrangement 16. Mainly differences with respect to Figs. 1-14 will be described. The base section 18 is connected to the frame 14 and the fixation part 20 is connected to the door leaf 12. The arrangement 16 in Fig. 15 comprises a linkage 64. The linkage 64 is a further example of a connection device according to the present disclosure.

The linkage 64 is arranged between the fixation part 20 and the base section 18, and is connected to the fixation part 20 and to the base section 18. The linkage 64 of this specific example comprises a first arm 66 pivotally connected to the fixation part 20 and a second arm 68 pivotally connected to the base section 18. The first arm 66 and the second arm 68 are pivotally connected to each other. The linkage 64 further comprises a third arm 70.

The third arm 70 is fixedly connected to the second arm 68. The arrangement 16 in Fig. 15 does not comprise an opening spring 28. The closing spring 44 acts on the linkage 64 to to pull the door leaf 12 to close. The closing spring 44 thereby exerts a force on the linkage 64 to force the base section 18 and the fixation part 20 towards each other in the relative closing movement 60. The arrangement 16 further comprises a viscous damper 72. The closing spring 44 provides a closing force on the door leaf 12 that increases with a degree of opening of the door leaf 12. The viscous damper 72 provides a damping force on the door leaf 12 in dependence of a speed of the door leaf 12.

In Fig. 15, the magnet 50 is distanced from the fixation part 20. The magnet 50 is provided on an end of the door leaf 12 opposite to the hinge 24. The arrangement 16 further comprises a magnetic target section 74. The magnetic target section 74 is fixed to the frame 14. The magnetic target section 74 of this example is a magnet.

Fig. 16 schematically represents a top view of the door system 10 in Fig. 15 when the door leaf 12 is in the closed position 26. During the last part of the closing movement 60 of the door leaf 12, the magnet 50 and the magnetic target section 74 are brought into proximity to attract each other to thereby reliably latch the door leaf 12 to the closed position 26. The magnet 50 and the magnetic target section 74 also force the base section 18 and the fixation part 20 to move towards each other by means of magnetic force. While the present disclosure has been described with reference to exemplary embodiments, it will be appreciated that the present invention is not limited to what has been described above. For example, it will be appreciated that the dimensions of the parts may be varied as needed. Accordingly, it is intended that the present invention maybe limited only by the scope of the claims appended hereto.