GB2391039A

GB2391039A - Electromagnetic frame lock

Info

Publication number: GB2391039A
Application number: GB0217019A
Authority: GB
Inventors: Robin Clive Vernon Humphries
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-23
Filing date: 2002-07-23
Publication date: 2004-01-28
Anticipated expiration: 2022-07-23
Also published as: GB2391039B; GB0217019D0

Abstract

A fastening mechanism 3 for a closure having an opening wing 1 movable towards and away from a closed position relative to a fixed frame 2. The fastening mechanism 3 comprises an electromagnetic shear lock unit 4 having an armature 4b on the wing 1 and an electromagnet 4a on the fixed frame 2. The armature 4b is adjustably mounted in a housing 7 attached to a side edge face 1a of the wing 1 such that the position of the armature 4b relative to the electromagnet 4a can be adjusted in mutually perpendicular directions to align the armature 4b with the electromagnet 4a and set the spacing therebetween in the closed position of the wing 1.

Description

2391 039

IMPROVEMENTS IN OR RELATING TO CLOSURES

This invention concerns improvements in or relating to closures of the type having an opening wing movable towards and away from a closed 5 position relative to a fixed frame, for example doors or windows.

The invention has particular, but not exclusive, application to electromagnetic fastening mechanisms for securing the opening wing in the closed position and more especially electromagnetic shear locks.

The invention also has application to arrangements for strengthening closures to resist forced entry and to use of such arrangements with a fastening mechanism for the closure, especially an electromagnetic fastening mechanism.

Electromagnetic shear locks are known in which a magnetic attraction force is created between two members mounted on the opening wing and fixed frame respectively to secure the opening wing in the closed position when an electromagnetic is energised.

Unauthorised opening of the wing may be resisted by the magnetic attraction force alone. Alternatively, one of the members may have at least one projection that engages an aligned opening in the other member to provide a mechanical interlock in addition to the magnetic attraction 25 force to resist opening movement of the wing.

The magnetic attraction force and, where provided any mechanical interlock is released when the electromagnet is de-energised to allow the wing to be opened.

Typically, the electromagnet is energised automatically when the wing is in the closed position to secure the wing relative to the frame and the electromagnet is de-energised by user operable means when it is desired to open the wing.

This type of fastening mechanism requires the alignment and spacing of the members in the closed position to be set accurately to ensure the magnetic attraction force is adequate to hold the wing in the closed position. Traditionally, the members are mounted in recesses in opposed side edges of the wing and frame. As a result, considerable care is required during installation to obtain the correct alignment and spacing in the closed position to obtain the required magnetic attraction force to secure the 15 wing in the closed position.

Problems can result if, in use, the initial alignment and spacing is lost.

For example the relative positions of the wing and frame may change due to wear, settlement, mix-use, vandalism or break-ins requiring re 20 positioning of the fastening mechanism to correct misalignment and/or spacing of the members.

Such re-positioning is time consuming and in some cases may require complete re-fitting of the fastening mechanism.

The present invention has been made from a consideration of the foregoing problems.

i Accordingly, the present invention seeks to provide a fastening mechanism, especially an electromagnetic fastening mechanism which can be installed simply.

5 The present invention further aims to provide an arrangement that allows adjustments to be made to the installed position for correcting misalignment and/or incorrect spacing between co-operating members of the fastening mechanism for securing an opening wing of the closure in a closed position.

The present invention also aims to provide an arrangement that reinforces the closure and can be used in combination with a fastening mechanism for securing an opening wing the closure in a closed position to assist in preventing forced entry.

It is a preferred object of the present invention to provide an electromagnetic fastening mechanism in which adjustment to the installed position can be made without completely disassembling the fastening mechanism. It is another preferred object of the present invention to provide such adjustment to the installed position in a shear type electromagnetic fastening mechanism.

25 According to a first aspect of the invention there is provided a fastening mechanism for a closure having an opening wing movable towards and away from a closed position relative to a fixed frame, the fastening mechanism comprising an electromagnetic lock unit having a first member for attaching to the wing, a second member for attaching to the frame, the 30 lock unit being operable to hold the wing in the closed position, wherein

l the lock unit includes means for adjusting the alignment and/or spacing between the members in the closed position of the wing.

By this invention, the operation of the lock unit to hold the wing in the 5 closed position can be optimised by adjusting the alignment and/or spacing between the members of the lock unit in the closed position.

In this way, installation is facilitated by permitting adjustments to be made to the installed position to achieve the required alignment and 10 spacing of the members.

Moreover, adjustments can be made to correct any misalignment or change in spacing that occurs in use. Accordingly, the fastening mechanism can be maintained to work satisfactorily at all times, The adjustment means may permit the position of one of the members to be adjusted relative to the other. In this arrangement, the position of the other member may be fixed. Alternatively, the adjustment means may permit the positions of both members to be adjusted relative to each 20 other. In this arrangement, one member may be adjustable to align the members and the other member adjustable to set the clearance gap between the members. Alternatively both members may be adjustable to align the members and set the clearance between the members.

25 In a preferred arrangement, the adjustment means permits the position of the first member on the wing to be adjusted and the position of the second member on the frame is fixed.

Advantageously, the adjustments means includes an elongate housing 30 arranged to extend lengthwise of an edge of the wing and having a

longitudinal channel in which the first member is received. In this way, the first member can be adjusted along the channel to align the first and second members in the closed position of the wing.

5 Preferably, the elongate housing is of approximately H-section having first and second longitudinal channels separated by a web with the first channel arranged to receive the first member and the second channel arranged to receive the edge of the wing.

10 Advantageously, the first member is located between opposed side walls of the first channel and has at least one projection received in a slot in the web to permit axial adjustment of the first member between the ends of the slot.

15 Preferably, the first channel is narrower than the second channel and side walls of the first channel are of different thickness such that the first channel is offset towards one side of the wing.

Advantageously, the first member comprises two parts, a base part and a 20 top part and the adjustment means includes an adjuster arranged to connect the parts for movement of the top part towards and way from the base part in a direction normal to the length of the channel.

In this way, the first member can be adjusted into or out of the channel to 25 set the spacing between the first and second members in the closed position of the wing.

The adjuster preferably comprises a bolt that is axially located relative to the top part and threadably engages the base part. In this way, the top

part is movable towards and away from the base part in response to rotation of the bolt in opposite directions.

In a preferred arrangement, two bolts are provided and each bolt projects 5 from the underside of the base part and locates in a slot in the web. In this way, the bolts can be adjusted independently to accommodate any variation in the size of the gap between the wing and frame, for example if the door and frame are out of square.

10 Preferably, the first member is fixed in the axially aligned position by the provision of in-fill blocks either side of the first member within the channel. The in-fill blocks may be made of wood or any other suitable material such as plastics to close the channel and provide an aesthetically pleasing finish The base part may be secured to the in-fill blocks, for example by screws.

With this arrangement, the top part may be adjusted towards and away from the base part to adjust the spacing between the members with the first member secured in situ within the channel.

The fastening mechanism may comprise a plurality of electromagnetic lock units arranged on one or more edges of the wing and frame. A plurality of lock units may be located at spaced apart positions along opposed edges of the wing and frame with the first members received in a 25 common housing.

Preferably, the electromagnetic lock unit is of the shear type in which the closure is held in the closed position by a magnetic attraction force between the first and second members.

In one arrangement, the second member is an electromagnet that is energised when the wing is closed such that the first member is attracted by the energised electromagnet to hold the wing in the closed position.

5 Preferably, the electromagnet is energised in response to detection of the wing in the closed position. For example a contact sensor actuated when the door is closed to cause the electromagnet to be energised.

The first member may be made of a magnetisable material such as a 10 ferromagnet or magnetised material such as a permanent magnet that is attracted to the electromagnet when the electromagnet is energised.

The electromagnet may be de-energised by any suitable means when it is desired to release the magnetic attraction force and allow the wing to be 15 opened. For example, actuation of a switch by a push button, key, swipe card, keypad, handle or other suitable user operable device.

In another arrangement, both the first and second members are electromagnets that are energised when the wing is closed to produce the 20 magnetic attraction force to hold the wing closed and that are de-

energised to allow the wing to be opened.

According to a second aspect of the invention, there is provided a closure comprising an opening wing movable towards and away from a closed 25 position relative to a fixed frame and a fastening mechanism according to the first aspect of the invention for securing the wing in the closed position. The closure may comprise a door or window.

According to a third aspect of the invention, there is provided a method of fitting a fastening mechanism to a closure having an opening wing movable towards and away from a closed position relative to a fixed frame comprising providing an electromagnetic lock unit having a first 5 member and a second member, positioning the first member on a side edge of the frame, positioning an elongate housing having a longitudinal channel on a side edge of the wing opposite the side edge of the frame, locating the second member in the channel and adjusting the position of the second member along the channel to align with the first member, 10 securing the second member in the aligned position to at least one in-fill block received in the channel, and adjusting the position of the second member transverse to the length of the channel to set the clearance between the first and second members in the closed position of the wing.

15 The closure may be a door or window.

According to a fourth aspect of the invention, there is provided a security fitting for a closure having an opening wing movable towards and away from a closed position relative to a fixed frame, the security fitting 20 comprising an elongate member having spaced sidewalls connected by a transverse web, a first longitudinal channel between the sidewalls on one side of the web for receiving an edge of the closure and a second longitudinal channel between the sidewalls on the other side of the web.

25 By this invention, the security fitting conceals the edge of the closure and provides reinforcement to strengthen locally the edge of the closure.

Preferably, the security fitting is provided along the edge of the closure that is secured to the frame in the closed position. In this arrangement,

the second channel may house or receive part of the fastening mechanism such that the security fitting provides protection against forced entry.

The second channel may include in-fill material to close-off the channel 5 and provide a neat finish. For example, the in-fill material may comprise wood or plastic to replicate the material of the closure.

In a preferred embodiment, the security fitting is provided in combination with the fastening mechanism according to the first aspect of the 10 invention. It will be understood, however, that the security fitting may be provided solely as a reinforcement for the edge of a closure or in combination with any type of fastening mechanism traditionally employed for securing the closure in the closed position.

15 An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a transverse section through a door and fixed frame incorporating a fastening mechanism embodying the invention, the 20 door being shown in the closed position; Figure 2 is a perspective view showing part of the door and fastening mechanism shown in Figure 1; 25 Figure 3 is a perspective view showing a detail of the fastening mechanism shown in Figure 2; Figure 4 is a side view, partly in section of the door and fastening mechanism shown in Figures 1 and 2;

Figure 5 is a perspective view of the mounting sleeve shown in Figures 1 and 2; Figure 6 is a transverse section of the mounting sleeve shown in l 5 Figure 5; and Figure 7 is a view of mounting sleeve in the direction of arrow X in Figure 6.

10 With reference to Figures 1 to 4 of the drawings, a door 1 is shown secured in a closed position (Figure 1) relative to a fixed frame 2 by an electromagnetic shear type fastening mechanism 3 according to the invention. 15 In this embodiment, the door 1 and frame 2 are made of timber but it will be understood that other materials may be employed for the door 1 and/or frame 2.

The door 1 is mounted for pivotal movement towards and away from the 20 closed position by a pair of hinges (not shown) defining a vertical hinge axis at one side of the door 1.

The fastening mechanism 3 is arranged at the other side of the door 3 and comprises vertically spaced upper and lower electromagnetic shear lock 25 units 4 and 5 (Figure 4) operable to provide a magnetic attraction force between opposed side edge faces la,2a of the door 1 and frame 2 to hold the door 1 closed.

It will be understood that the number and arrangement of the 30 electromagnetic lock units may be varied. For example, the fastening

mechanism 3 may comprise one or more electromagnetic lock units positioned on opposed faces of the door 1 and frame 2 at the side and/or top and/or bottom of the door.

5 In addition to the electromagnetic lock units 4, 5, the door may be provided with additional locking means providing added security in the closed position, for example a key operated lock such as a mortice lock.

Each electromagnetic lock unit 4,5 is similar and comprises an 10 electromagnet 4a,5a mounted on the fixed frame 2 and an armature 4b,5b mounted on the door 1.

For convenience, the construction, installation and operation of the upper lock unit 4 will now be described in more detail, it being understood that 15 the description applies to the lower lock unit 5.

The electromagnet 4a is mounted in a recess 6 cut into side edge face 2a of the frame 2 so that the outer face of the electromagnet 4a is flush with the side edge face 2a of the frame 2. In this way, the position of the 20 electromagnet 4a is fixed.

The electromagnet 4a is connectable to an electrical power supply via a control device (not shown) for energising/de-energising the electromagnet 4a as described later.

The armature 4b is mounted on the opposed side edge face la of the door 1 in a housing 7 attached to the side edge face la to permit adjustment of the position of the armature 4b relative to the electromagnet 4a in mutually perpendicular directions relative to side edge face la of the door 30 1 to align the armature 4b with the electromagnet 4a and to set the

spacing between the armature 4b and electromagnet 4a in the closed position of the door 1.

With reference now to Figures 5 to 7, the housing 7 is of approximately 5 H-shape in transverse cross-section having two longitudinally extending channels 8,9 separated by a web 10. The housing 7 extends the length of the side edge of the door 1 and in this embodiment is cut to length from an extrusion of aluminium, It will be understood, however, that the housing 7 can be made of other materials and may be formed by extrusion 10 or other suitable methods.

The channel 8 has opposed parallel side walls 11,12 of equal thickness extending from one side of the web 10. The channel 8 is dimensioned to receive the side edge of the door 1 and the housing 7 is secured to the 15 door 1 by fasteners (not shown) such as screws having tamper-proof heads. In this way, the housing 7 reinforces the side edge of the door 1.

The channel 9 has opposed parallel side walls 13,14 of unequal thickness extending from the other side of the web 10. The channel 9 is 20 dimensioned to receive the armature 4b and in-fill blocks 15 of wood to close-off the channel 9. It will be understood that the in-fill blocks 15 may be made of other suitable material, for example plastics.

The channel 9 is narrower than the channel 8 and is offset to one side of 25 the housing 7. This is shown by the dotted lines 16 and 17 in Figure 7.

Dotted line 16 shows the centre of channel 8 and dotted line 17 shows the centre of channel 9. In this way, the electromagnetic lock units 4,5 are offset towards the closed face of the door 1 in the closed position (Figure 1).

The armature 4b comprises a base part 18 and a top part 19 secured together by a pair of bolts 20,21 having hexagonal heads 20a,21a recessed in the outer surface of top part 19 and threaded shanks 20b,21b that project from the underside of base part 18. The top part 19 is made of a 5 magnetizable material such as iron, eg a ferromagnet.

The armature 4b is a close fit between the side walls 13,14 of the channel 9 to prevent sideways movement of the armature 4b within the channel 9.

The free ends of the threaded shanks 20b,21b are received in a pair of 10 axial slots 22,23 formed in the web 10.

The slots 22,23 are positioned on the centre line 17 of the channel 9 and permit limited axial sliding movement of the armature 4b lengthwise of the channel 9 between end positions defined by engagement of the shanks 15 20b,21b with the ends of the slots 22,23.

The length of the slots 22,23 may be varied to permit any desired range of adjustment and the slots 22,23 may be combined in a single slot. In this way, the axial position of the armature 4b along the channel 9 can be 20 adjusted to align accurately the armature 4b with the fixed electromagnet 4a on the frame.

The threaded shanks 20b,21b project slightly through the web 10 and the side edge face la of the door 1 is cut away behind the slots to allow free 25 movement of the shanks 20b,21b along the slots 22,23.

The armature 4b is located in the aligned position by the in-fill blocks 15 that are cut to the required length when the axial position of the armature 4b in the channel 9 has been determined.

The in-fill blocks 15 are secured in the channel 9 by any suitable means (not shown) and are dimensioned so that the outer surface of the blocks 15 is flush with the outer ends of the side walls 13,14 (Figure 2).

5 The base part 18 of the armature 4b has flanges 24,25 at opposite ends that overlie the adjacent ends of the blocks 15 and are provided with holes (not shown) by means of which the base part 18 is secured to the blocks 15 by screws 26.

10 In this way, the armature 4b can be accurately aligned with the electromagnet 4a during initial installation and fixed in the aligned position by attaching to the in-fill blocks 15. The alignment can also be adjusted in use by removing the in-fill blocks 15 either side of the armature 4b, re-positioning the armature 4b along the channel 9 and re 15 fitting in-fill blocks 15 of the appropriate size.

The bolts 20,21 threadably engage base part 18 of the armature 4b and are located against axial movement relative to the top part 19 of the armature 4b so that rotation of the bolts 20,21 causes the top part 19 to 20 move towards and away from the base part 18.

In this way, the spacing between armature 4b and the electromagnet 4a in the closed position of the door 1 can be accurately set by adjusting the position of the top part 19 to adjust the clearance gap between the outer 25 surface of the top part 19 and the outer surface of the electromagnet 4a in the closed position.

Such adjustment can be carried out both during initial installation and in use to correct any change in the spacing due to wear or settlement or 30 from mis-use or vandalism or any other cause.

In use, when the door 1 is closed (Figure 1), the housing 7 locates against abutment face 27 of frame 2 and armatures 4b,5b of the electromagnetic lock units 4,5 align with the electromagnets 4a,5a. The electromagnets 5 4a,5a are energised via the control system by any suitable means, for example in response to a signal from a sensor (not shown) arranged to detect the door 1 in the closed position.

As a result, the door 1 is held in the closed position by the magnetic 10 attraction force created between the armatures 4b,5b and the aligned electromagnets 4a,5a respectively.

When it is desired to open the door 1, the electromagnets 4a,5a are de-

energised via the control system by any suitable user operable means, for 15 example with a key, swipe card, switch etc. As a result, the magnetic attraction force between the armatures 4b,5b and the electromagnets 4a,5a is dissipated and the door 1 can be opened.

The electromagnets 4a,5a are re-energised when the door 1 is closed. In 20 this way, the door 1 is held in the closed position each time the door 1 is closed. If, during use, the alignment and/or spacing of the armatures 4b,5b relative to the electromagnets 4a,5a is altered for any reason such as 25 general wear and tear or because of damage caused by vandalism or mis-

use, the magnetic attraction force may be insufficient to hold the door 1 satisfactorily in the closed position.

In this case, the position of the armatures 4b,5b can be adjusted relative 30 to the electromagnets 4a,5a by moving the armatures 4b,5b longitudinally

and or transversely with respect to the channel 9 to re-align the armatures 4b,5b with the electromagnets 4a,5a and/or re-set the spacing between the armatures 4b,5b and the electromagnets 4a,5a.

5 As will now be appreciated, the arrangement of the armatures 4b,5b in the channel 9 facilitates accurate alignment of the armatures 4b,5b with the electromagnets 4a, 5a and accurate setting of the gap between the armatures 4b, 5b and the electromagnets 4a, 5a both during initial installation and in use, if adjustments to the alignment and/or spacing is 10 required.

In this way, installation and repair/maintenance is simplified compared to existing arrangements in which the positions of the armatures 4b,5b and the electromagnets 4a,5a are fixed on installation.

It will be understood that the above-described fastening mechanism may be fitted as original equipment to a new door and frame. Alternatively, the fastening mechanism may be retro-fitted fitted to an existing door and frame. When retro-fitting to an existing door and frame, the edge of the 20 door will require trimming to fit the sleeve so that the overall dimensions of the door are unchanged.

Although the invention has been described for application of the fastening mechanism to a door, it will be appreciated that the invention has 25 application to other types of closures including windows.

It will also be understood that the invention is not limited to the embodiment above-described and that various modifications can be made as will be apparent to those skilled in the art.

For example, the electromagnet may be located on the side edge of the door and the armature on the edge of the frame. In this arrangement, the electromagnet may be fixed and the armature adjustable in a channel on the frame to align with the electromagnet and set the clearance 5 therebetween.

Alternatively, the armature may be fixed and the electromagnet adjustable in a channel on the frame or door to align with the armature and set the clearance therebetween. In another arrangement, both the armature and 10 electromagnet may be adjustable to align with each other and set the clearance therebetween In addition to the magnetic attraction force created to hold the door closed, the armature may include one or more locking pins that are 15 attracted to engage aligned holes in the electromagnet when the electromagnet is energised to provide a mechanical interaction for added security. It will also be understood that the invention is not limited to 20 electromagnetic fastening mechanisms of the shear type and may be applied to other types of electromagnetic fastening mechanisms as will be familiar to those skilled in the art.

It will also be appreciated that from another aspect, the invention includes 25 use of the housing as a reinforcement for the edge of a closure either separately or in combination with a fastening mechanism of any type.

Claims

1. A fastening mechanism for a closure having an opening wing movable towards and away from a closed position relative to a fixed 5 frame, the fastening mechanism comprising an electromagnetic lock unit having a first member for attaching to the wing, a second member for attaching to the frame, the lock unit being operable to hold the wing in the closed position, wherein the lock unit includes means for adjusting the alignment and/or spacing between the members in the closed position of 10 the wing.

2. A fastening mechanism according to claim 1 wherein the adjustment means permits the position of one of the members to be adjusted relative to the other.

3. A fastening mechanism according to claim 2 wherein the position of the other member is fixed.

4. A fastening mechanism according to claim 1 wherein the 20 adjustment means permits the positions of both members to be adjusted relative to each other.

5. A fastening mechanism according to claim 4 wherein one member is adjustable to align the members and the other member is to set the 25 clearance gap between the members.

6. A fastening mechanism according to claim 4 wherein both members are adjustable to align the members and set the clearance between the members. .

lo

7. A fastening mechanism according to claim 3 wherein the adjustment means permits the position of the first member on the wing to be adjusted and the position of the second member on the frame is fixed.

5

8. A fastening mechanism according to any one of the preceding claims wherein the adjustment means includes an elongate housing arranged to extend lengthwise of an edge of the wing and having a longitudinal channel in which the first member is received.

10

9. A fastening mechanism according to claim 8 wherein the elongate housing is of approximately H-section having first and second longitudinal channels separated by a web with the first channel arranged to receive the first member and the second channel arranged to receive the edge of the wing.

10. A fastening mechanism according to claim 9 wherein the first member is located between opposed side walls of the first channel and has at least one projection received in a slot in the web to permit axial adjustment of the first member between the ends of the slot.

11. A fastening mechanism according to claim 9 or claim 10 wherein the first channel is narrower than the second channel and side walls of the first channel are of different thickness such that the first channel is offset towards one side of the wing.

12. A fastening mechanism according to any one of claims 8 to 11 wherein the first member comprises two parts, a base part and a top part and the adjustment means includes an adjuster arranged to compact the parts for movement of the top part towards and way from the base part in 30 a direction normal to the length of the channel.

13. A fastening mechanism according to claim 12 wherein the adjuster comprises a bolt that is axially located relative to the top part and threadably engages the base part such that the top part is movable towards 5 and away from the base part in response to rotation of the bolt in opposite directions.

14. A fastening mechanism according to claim 13 wherein two bolts are provided and each bolt projects from the underside of the base part 10 and locates in a slot in the web such that the bolts can be adjusted independently to accommodate any variation in the size of the gap between the wing and frame.

15. A fastening mechanism according to any one of claims 8 to 14 15 wherein the first member is fixed in the axially aligned position by the provision of in-fill blocks either side of the first member within the channel.

16. A fastening mechanism according to claim 15 wherein the infill 20 blocks are made of wood or plastics.

17. A fastening mechanism according to claim 15 or claim 16 wherein the base part is secured to the in-fill blocks.

25

18. A fastening mechanism according to claim 17 wherein the top part is adjusted towards and away from the base part to adjust the spacing between the members with the first member secured in situ within the channel.

19. A fastening mechanism according to any one of the preceding claims wherein a plurality of electromagnetic lock units are arranged on one or more edges of the wing and frame.

5

20. A fastening mechanism according to claim 19 wherein a plurality of lock units are located at spaced apart positions along opposed edges of the wing and frame with the first members received in a common housing.

2. A fastening mechanism according to any one of the preceding 10 claims wherein the or each electromagnetic lock unit is of the shear type in which the closure is held in the closed position by a magnetic attraction force between the first and second members.

22. A fastening mechanism according to claim 21 wherein the second 15 member is an electromagnet that is energised when the wing is closed such that the first member is attracted by the energised electromagnet to hold the wing in the closed position.

23. A fastening mechanism according to claim 22 wherein the 20 electromagnet is energised in response to detection of the wing in the closed position.

24. A fastening mechanism according to claim 23 wherein a contact sensor is provided that is actuated when the door is closed to cause the 25 electromagnet to be energized.

! 2.., -...

25. A fastening mechanism according to any one of claims Auto 24 wherein the first member is made of a magnetizable material. 7; ! it,, ' 1;', :r. ..

26. A fastening mechanism according to claim 25 wherein the first member is a ferromagnet.

27. A fastening mechanism according to any one of claims 21 to 24 5 wherein the first member is made of magnetised material.

28. A fastening mechanism according to claim 27 wherein the first member is a permanent magnet.

10

29. A fastening mechanism according to any one of claims 21 to 28 wherein the electromagnet is de-energised by any suitable means when it is desired to release the magnetic attraction force and allow the wing to be opened.

15

30. A fastening mechanism according to claim 29 wherein the electromagnet is de-energised by actuation of a switch.

31. A fastening mechanism according to claim 30 wherein the switch is operable by a push button, key, swipe card, keypad, handle.

32. A fastening mechanism according to any one of claims 1 to 21 wherein both the first and second members are electromagnets that are energised when the wing is closed to produce the magnetic attraction force to hold the wing closed and that are de-energised to allow the wing 25 to be opened.

33. A fastening mechanism substantially as hereinbefore described with reference to the accompanying drawings . if,.. 1.....

34. A closure comprising an opening wing movable towards and away from a closed position relative to a fixed frame and a fastening mechanism according to any one of the preceding claims for securing the wing in the closed position.

35. A closure according to claim 34 comprising a door or a window.

36. A method of fitting a fastening mechanism according to any one of claims 1 to 33 to a closure having an opening wing movable towards and 10 away from a closed position relative to a fixed frame, the method comprising providing an electromagnetic lock unit having a first member and a second member, positioning the first member on a side edge of the frame, positioning an elongate housing having a longitudinal channel on a side edge of the wing opposite the side edge of the frame, locating the 15 second member in the channel and adjusting the position of the second member along the channel to align with the first member, securing the second member in the aligned position to at least one in-fill block received in the channel, and adjusting the position of the second member transverse to the length of the channel to set the clearance between the 20 first and second members in the closed position of the wing.

37. A security fitting for a closure having an opening wing movable towards and away from a closed position relative to a fixed frame, the security fitting comprising an elongate member having spaced sidewalls 25 connected by a transverse web, a first longitudinal channel between the sidewalls on one side of the web for receiving an edge of the closure and a second longitudinal channel between the sidewalls on the other side of the web for receiving part of the fastening mechanism according to any one of claims 1 to 33.

38. A security fitting according to claim 37 wherein the elongate member conceals the edge of the closure and provides reinforcement to strengthen locally the edge of the closure.

5

39. A security fitting according to claim 37 or claim 38 wherein, in use, the elongate member is secured along the edge of the closure that is secured to the frame in the closed position.

40. A security fitting according to any one of claims 37 to 39 wherein 10 the second channel includes in-fill material to close-off the channel.