GB2183290A - Device for controlling the movement of a door - Google Patents

Abstract

The device, particularly for controlling the closing movement of a door (11, Fig. 6), comprises a linkage mechanism (45, 46, 47, 51) connected between the frame (10) and a door closer device (15) mounted on a backplate (13). Backplate-mounted means to retain the door open has a spring-biased arm (34, Fig. 2) movable downwards against spring (42) bias until a linkage part (51) on a catchplate (47) passes over, whereupon the arm rises so that a surface (38, Figs. 2 and 6) of the arm holds the linkage and door open. In manually shutting the door, the arm (34) is thrust down by the linkage part (51) so that the closer operates. To automatically shut the door, where fire is detected, an electromagnet is released to allow an arm (19) to pivot under spring bias and thus allow the spring-biased arm (34) to move axially and release the door. If the catch plate (47, Fig. 6) is free of the main arm (45) the door is free-swinging once it is moved to an open position. Accordingly simple fixing means (49, 50) are used so that conversion from a free-swinging door to a held open door or vice versa can easily be carried out. In the event of a fire however, the door is automatically closed by the released catchplate, regardless of whether it is in a free-swinging or held open state. <IMAGE>

Description

SPECIFICATION Device for Controlling the Movement of a Door This invention relates to a device for controlling the movement of a door, hingedly connected to a frame in the conventional manner, and is particularly, though not exclusively, concerned with the automatic closing in the event of a fire, of a door which is normally either held open or is freeswinging over at least part of its opening or closing movement.

In hospitals, old people's homes and similar establishments it is often desirable for doors to be free-swinging or, if fitted with a door closer, normally to be held open, so that aged or inform people in such estabiishments are relieved of the effort required to open the door against the force of a door closer. However it is naturally desirable that any open door should automatically close should a fire occur in order to try to prevent it spreading.

The object of the invention is to provide a device for controlling the movement of a door in a simple and effective manner.

According to the present invention there is provided a device for controlling the movement of a door hingedly connected to a frame, comprising a member biassed to rotate in one direction, and retaining means operable to hold said member against the bias acting thereon, but which means can be released or overcome for the member to pivot, by virtue of the bias, in said one direction, the arrangement being such that, in use, the retaining means and said member are mounted at one of the door and the frame, and the member is normally held at rest by the retaining means, release of said retaining means of the overcoming thereof, freeing said member so that it directly or indirectly moves the door to a closed or open position, wherein the retaining means include a catch element which is movable by said member from a first to a second position upon movement of said member past it against said bias, the catch element thereafter returning to said first position and retaining the member against rotation in said one direction, and a retaining element engaging the catch element in said first and second positions and preventing it moving in a direction to release said retained member, the catch element, on release of or on the overcoming of the retaining element, moving in said direction to release the member.

According to another aspect of the invention there is provided a linkage mechanism for use in a device for controlling the movement of a door hingedly connected to a frame, comprising a spindle, a catch member connected to or integral with the spindle for rotation therewith, an arm carried by the spindle and freely rotatable thereon, the catch member and the arm having respective openings therein at least part of each of which can be aligned, and fixing means for passing through said aligned parts ofthe openings to secure the arm to the catch member, or for passing through said opening in the catch member only, at one side of the arm, so that the arm can move angularly away from the fixing means in one direction and engages the fixing means upon angular movement in the opposite direction.

According to a further aspect of the invention there is provided a device for controlling the movement of a door hingedly connected to a frame, comprising a linkage mechanism as described in the previous paragraph, wherein the spindle is biassed to rotate in one direction together with said catch member, and retaining means are provided which are operable to hold the catch member, and thus the spindle, against said bias, but which can be released or overcome for said catch member to move angularly, by virtue of the bias, in said one direction, the arrangement being such that, in use, the retaining means and the spindle are mounted at one of the door and the frame, and the catch member is normally held at rest by the retaining means, release of said retaining means or the overcoming thereof, freeing said catch member so that, by way of said arm, it moves the door to an open or closed position.

The invention will now be described, byway of example, with reference to the accompanying drawings, in which: Figure lisa side view of part of a device for controlling the movement of a door constructed in accordance with the present invention, Figure 2 is a plan view of the device shown in Figure 1, with some parts thereof omitted for clarity, Figure 3 is a sectional view on the line A-A of Figure 2, but including the parts shown in Figure 1 and omitted in Figure 2, with a door closer and a cover also being shown, Figures 4 and 5 are a part-sectional side view and a top plan view respectively, of part of an arm mechanism of the device of the invention, Figure 6 is a diagrammatic plan view of the operation of the device, in use, when secured to a door and frame, with the door being shown closed and also shown opened to a position where it is held open by the device of the invention, Figure 7 is a diagrammatic front view of the arrangement of Figure 6, Figure 8 is a fragmentary exploded view showing how part of the arm mechanism of a first embodiment of the device of the invention can be converted so that the device operates according to a second embodiment of the invention, Figure 9 is a fragmentary cross-sectional view of part of the converted arm mechanism, Figure 10 is a plan view of the converted arm mechanism, for the opposite hand to Figure 8, and Figure 11 is a view similar to Figure 6, showing sequential operation of the device of said second embodiment, in use, with the door being shown closed, then opened to 900 and then closed to 45 .

In the embodiment of the invention shown in Figures 1 to 7, a conventional door frame 10 has a door 11 connected to it by hinges 12. Along the top of the door 11 is secured a rectangular steel backplate 13. The backplate carries a pair of longitudinally spaced aluminium spacer blocks 14, and supported by and secured to these blocks is a door closer 15 of any convenient form, having a conventional spindle 16, the rotation of which moves a piston in a hydraulically filled chamber of the closer in the usual manner. The closer has an associated arm mechanism shown in Figures 4 to 7, which will be described later, and a cover 15a.

Spaced from one end of the door closer, there is secured to the backplate 13 a pair of spaced apart supports 17, each providing a flange 18 extending normally from the backplate, with the flanges 18 lying parallel to the longer sides of the backplate.

The space between the supports is open towards the door closer. Pivotally mounted between the parallel flanges 18 is a generally U-shaped lever 19.

Parallel sides 20 of the lever lie adjacent the flanges 18 of the supports 17, with a base 21 of the lever being towards the door closer and being extended away from the sides 20 to form an extension 21 a. A lever pivot pin 22 extends through the sides 20 of the lever 19 and also the flanges 18 of the supports 17, at a position spaced somewhat from the surface of the backplate to which the supports 17 is secured.

The pin 22 has, in this example, securing clips 23 at its ends and spacer washers between the flanges 18 and sides 20. Between one flange 18 and an adjacent securing clip 23, a coiled torsion spring 24 is received on the pin 22 to bias the lever 19 to the position shown.

Atthe open end of the lever 19, there is provided a lever roller pin 25 secured between the sides 20, the pin 25 carrying a lever roller 26. With the base 21 of the lever disposed normal to the surface of the backplate, as shown in Figure 2, the axis of the pin 25 is in a plane parallel to the backplate surface, this plane also containing the axis of the pivot pin 22.

The diameter of the roller 26 is such that it is spaced above the surface of the backplate when the base 21 is normal thereto. The ends of the pin 25 project through slots 27 in the flanges 18 so as to allow pivotal movement of the lever 19 relative to the supports 17, and the free ends of the spring 24 engage an end of the pin 25 and a base 28 of one of the supports 17 respectively.

The extension 21a of the lever has secured to its side facing the bracket 17, a keeper disc buffer 29 and a steel keeper disc 30. Secured between the flanges 18 of the supports 17 is an electromagnet 31.

As mentioned, the lever is biassed to a position where its base 21 is normal to the backplate, and in this position the keeper disc contacts a front face of the electromagnet.

The one of the spacer blocks 14 adjacent the supports 17 has a slot 32 in its underside and a steel holding claw 33 extends along the surface of the backplate from the bases of the supports 17, through the slot 32, to a position behind the door closer beyond the line of the spindle 16. The claw 33 is symmetrical about a longitudinal centre line and has an elongated rectangular shank portion 34 extending from the supports 17. At the end of the shank portion 34 adjacent the supports 17, there is secured a domed pressure button 35. With the lever 19 positioned as in Figures 1 and 3, with its associated keeper disc in contact with the electromagnet, the roller 26 is held down on the button 35, and this prevents any longitudinal movement of the claw 33.

The end of the claw behind the door closer is formed as an enlarged lateral extension, riveted to the shank portion 34, and having a maximum width slightly greater than that of the backplate 13. The extension is formed as a neck 36 extending from the shank portion 34 with divergent straight sides, and leading to an end part 37 which is of increasing width from its free end to its junction with the neck, where there are formed a pair of engagement or catch surfaces 38 at respective opposite sides of the part 37. Each surface 38 is at an angle of slightly less than 90" to the longitudinal centre line of the claw.

In the centre of the part 37 is a symmetrical, generally triangular aperture 39 having a substantially straight rear surface 40 normal to the claw longitudinal centre line and two surfaces 40a of equal length extending from the ends of the surface 40 and meeting on the claw centre line. Fixed to the backplate 13 and extending through the aperture 39 is a headed bolt 41. Freely rotatably carried on the bolt is a flanged guide roller 41a, the flange lying slightly beyond the surface of the claw containing the aperture 39 and slightly behind the head of the bond 41.The backplate has a pair of spring anchor pins 42 symmetrically disposed on opposite sides of a longitudinal centre line thereof and in the embodiment shown in Figures 1 to 7 the upper pin 42 anchors one end of a coiled tension spring 42a, the other end of which is similarly anchored by means of a fixing washer 43 and a spring anchor pin 44 on the shank portion of the claw. The claw is thus biassed by the spring 42 to the position shown in full lines in Figure 2, where the upper surface 38 and adjacent portion of the part 37 project upwardly beyond the top edge surface of the backplate 13. In this position, the roller 41a engages or substantially engages the rear surface 40 of the aperture 39, as also shown in full lines, in Figure 2.

Secured to the spindle 16 for rotation therewith is a main arm 45 of an arm mechanism of the door closer. At its end remote from the spindle 16 the main arm is pivotally connected to one end of a secondary arm 46, the other end of which is pivotally connected by a strip 46b to a bracket 46a for connection to a door or frame as will be described. As shown in Figure 5, the secondary arm 46 may be provided with apertures to allow the strip 46b to be received within it by varying amounts, so that the length of the secondary arm can be varied.

The main arm 45 lies in a plane spaced above the maximum upward projection of the claw shown in Figure 2. However the spindle 16 also carries a catch plate 47 disposed underneath the main arm at the level of the normal claw projection, the catch plate being secured against rotation on the spindle by a pin 16a. The catch plate is generally sector shaped and has an arcuate slot 48 therein. The underside of the slot 48 is grooved as shown at 48a and the slot is divided into three equal sections by constrictions 48b. The catch plate has a rectangular extension 51 at its end remote from the spindle 16, the extension extending centrally relative to the extent of the slot 48. The extension has a leading surface 52 and a parallel trailing surface 53 which extend sufficiently from the spindle 16 so as to contact the projecting part of the claw as will be described.The main arm has a through aperture 45a to receive the shank of a bolt 49 which also passes upwardly through one of the slot sections in the catch plate, with a head of the bolt being received in the grooved part 48a. This prevents rotation of the bolt and disposes the head clear of the top of the door closer. A nut 50 is tightened down onto a washer disposed on the upper surface of the main arm 45, thereby clamping the main arm to the catch plate. Awasher is also provided between the two clamped parts.

In use the backplate 13 and the bracket 46a are in this example secured to a door and associated frame respectively at the "pull face" thereof. As shown in Figures 6 and 7 the bracket 46a is secured to the transverse uppermost part of the frame and the backplate 13 is secured to the top of the door. In this arrangement the secondary arm 46 is normal to the door and the main arm 45 at an angle thereto.

The catch plate 47 is clamped to the main arm so that it will engage the claw at a particular angle of the door opening. With the electromagnet 31 energised, the keeper disc 30 is attracted to it and the lever 19 is thus in its Figure 1 position preventing longitudinal movement of the claw 33.

The nut and bolt clamping is intended to be arranged at the end sections of the slot respectively for the opposite hands of the device, so that, in this example, the claw 33 is engaged by the extension 51 at 103--110" of door opening, the actual angle depending on the position of the nut and bolt in the slot end section. If the clamping is at the centre section of the slot, however, the engagement takes place, in this example, at 90+5 of door opening, the actual angle again depending on the position of the clamping along the centre section of the slot.

Operation of the device will hereinafter be described with clamping in the centre section of the slot.

If the door is opened, the main arm and catch plate rotate the spindle 16 clockwise as viewed in Figure 6, and the opening is thus opposed by the force of the door closer 15 in the usual manner. As the opening movement of the door continues, a position is reached where the leading surface 52 of the catch plate engages the projecting surface of the part 37 of the claw. The shape of the surface 37 enables the catch plate extension 51 to depress the claw against the tension spring 42a from the position shown in full in Figure 2, to the position shown in the dashed line. This movement is permitted despite the roller 26 pressing down on the button 35, since it does not effectively involve longitudinal movement of the claw, only a slight downwards pivotal movement. This movement of the claw causes the rear surface 40 of the aperture 39 to move down against the roller 41 a.

As the opening of the door continues to the 90" open position of Figure 6, the extension 51 of the catch plate 47 passes over the depressed partofthe claw, which thus springs back into its normally biassed position, with the projecting portion of the claw now disposed behind the trailing surface 53 of the catch plate. Thus if the door opening force is now removed, the door closer force will try to close the door by rotating the spindle 16. However the spindle cannot rotate anti-clockwise beyond the position of 90" opening where the surface 53 engages the claw surface 38 (Figure 6). The door is thus held open.The actual degree of opening at which the hold open operation occurs can be altered by altering the relative angular relationship between the catch plate and main arm, by means of adjustment in the slot 48 of the bolt 49 with the nut 50.

Release of the door can be carried out in two ways, namely automatically and manually. As far as automatic release is concerned, this is required, for example, in the case of fire where it is important to close all doors to prevent the fire spreading.

Accordingly the fire alarm system would be arranged to de-energise the electromagnet 31 in the event of the system detecting a fire. This deenergisation would mean that the keeper disc 30 would no longer be held captive and similarly that the engagement of the roller 26 on the button 35 could now be overcome. Thus the force of the door closer acts through the spindle 16 to the catch plate 47 to force the claw longitudinally, and as a result of the action of the lower surface 40a being guided by the roller 41 a, downwardly, to the position shown in Figure 1 in dash-dot lines, against the force of the spring 42a. Once the extension 51 has cleared the projecting part of the claw, the spring 42a returns the claw to its normal position. Thus the door then closes under the action of the door closer in the normal manner.

If however it is wished to initiate closing of the door manually, this can be carried out merely by applying a pulling force to the door handle which is sufficiently large to overcome the force which prevents the claw moving longitudinally. The application of such a force will cause the catch plate 47 to push the projecting part of the claw 33 longitudinally and then downwardly to the position shown in dash-dot lines, so that it can move over it, the spring 42a returning the claw to its normal projecting position thereafter, and the door closing under the action of the door closer 15. The force applied to move the claw thus breaks the contact between the keeper disc 30 and electromagnet 31, but this can be restored once the catch plate 47 is clear of the claw, so that the next opening of the door beyond the predetermined amount required will cause the door again to be held open.

The device is easily adapted for use with either hand of the door. All that is required is the change of the anchoring of the one end of the spring 42a from the anchor pin 42 shown used in Figure 1, to the other anchor pin 42, so that the claw projects from the opposite, longer backplate edge. The backplate can then be secured to the oppositely handed door merely by making said opposite longer backplate edge uppermost.

Figures 8 to 11 show a second embodiment of the invention, where the door can be placed in a freeswinging mode, whilst still being automatically closed in the event of fire.

This device is the same as that of Figures 1 to 7 and differs only in the arrangement of the catch plate in relation to the main arm. Namely to use the device so that the door is free-swinging, it is merely necessary to rearrange and reposition the nut 50 and bolt 49, in conjunction with a spacer sleeve 54, so that in contrast to the first embodiment, the device of the second embodiment does not have its catch plate clamped to the main arm.

Accordingly to convert the linkage mechanism, the nut 50 is undone, releasing the bolt 49. The bolt is then removed from the hole 45a in the main arm and arranged in the slot section furthest away from the door hinge and at one side of the main arm 45. A cylindrical spacer sleeve 54 is then placed on the bolt stem as a close fit and the nut is placed on the end of the stem and screwed tightly down onto the sleeve, to the position best shown in Figure 9. The angle of free-swing of the door depends upon the position of the bolt in the slot section.For the position shown in Figure 10 the free-swing angle is approximately 85". Movement of the bolt to the closed end of the same slot section would increase the angle to approximately 95". Figure 8 shows the conversion for one hand and Figure 10 shows the conversion for an oppositely handed device.

Thus, in use, with the relative orientation between the main arm 45 and catch plate 47 as shown in Figures 10 and 11 for a door hinged on the right at the pull face the spacer 54 normally engages the side of the main arm 45. The door can then be opened against the force of the door closer until (at 85" opening in the example illustrated) the leading side surface 52 of the catch plate 47 engages the surface 37 of the claw, depresses the claw and passes over it, so as thereafter to be retained behind the surface 38, as with the device of the first embodiment.

As soon as the catch plate 47 is held by the claw 33, a manual closing movement of the door will cause the main arm 45 to disengage from the catch plate and thus freely pivot on the spindle 16. The door is then free-swinging. The door can be opened by 85" before the main arm 45 itself swings over the projecting part of the claw and again engages the sleeve 54 of the catch plate. Any further opening of the door is thus against the force of the door closer as the main arm rotates the catch plate away from the claw. On release, the closer will drive the catch plate, main arm and door back to the 85" open position, at which point the claw again retains the catch plate and the door is free-swinging.

The arrangement and operation described assumes that the electromagnet 31 is energised to hold the keeper disc 30 and thus prevent longitudinal movement of the claw. As long as this condition is maintained the door remains freeswinging from its fully closed position to its 85" open position, by virtue of the catch plate being held by the claw and being unable to rotate the spindle 16 to close the door. Thus the arrangement is particularly desirable for the elderly and infirm who can thus open the door without having to overcome the usual force of the door closer.

However in the event of fire, the door is nevertheless still automatically closed, whatever its degree of opening. As with the first embodiment, it is assumed that the power supply to the electromagnet would be cut off in the event of a fire being detected, so that the force of the door closer would cause the catch plate to move the claw longitudinally and depress it, thereby releasing itself from behind the surface 38. The catch plate would then rotate under the door closer force and engage, by way its sleeve 54, the main arm, automatically to close the door. Figure 11 shows a possible power supply arrangement from a connecting box 55 via an armoured cable 56 to the electromagnet.

Alternativeiy conducting hinges could be used.

Once the door is automatically closed in the event of fire, the next opening of the door to 85" followed by a closing movement will once again place the door in the free-swinging mode provided the electromagnet has been re-energised to prevent longitudinal movement of the claw, and the door will remain free-swinging until the catch plate again passes back over the claw.

Like the device of the first embodiment, the handing of the device of Figures 8 to 11 is easily changed merely by changing over the spring 42a from the upper one of the pins 42 to the other of the pins 42 and inverting the device. Similarly the device of Figures 8 to 11 can also be fixed to the door frame and the bracket 46a to the door, instead of the arrangement described and illustrated.

The provision of the constrictions 48b to form three discrete slot sections is advantageous in that it prevents the bolt slipping any more than a short distance along the slot if it is not tightly secured. If such slipping occurred along the whole slot length, a loss of latching or tension could occur. However a slot without constrictions or other dividing means could of course be used, as could a number of separate slots.

The linkage mechanism of the invention can thus be easy adapted to change a door movement controlling device from one for use with a freeswitching to one for use with a held open door and vice versa. No special tools are required since only tightening and release of the nut is required.

Moreover the only extra component is required is the sleeve 58.

In both embodiments the power forces are effectively utilised to prove an efficient and convenient device.

One advantage of the device of the invention is that the design of the toggle lever 19 permits the use of a less powerful electromagnet with appropriate lower power consumption. A further advantage is that door closers of any strength can be used, thereby widening the range of application to larger sizes of door. Previous free-swing designs using a single arm has been found to be limited to the lowest power and thus to smaller doors. This is due to the weak or "lazy" arm geometrical action of a single arm. The use of an extra arm is thus preferable and advantageous. Another advantage with the claw mechanism is that its "settle back" time after passage of the catch plate is very small (effectively nil) compared to that for a gravity flap arrangement, for example. Finally, the device of the invention can be mounted on the door face as well as on the head. This overcomes problems with previous devices which could only be head mounted, where sufficient substance or space was not always available.

Claims (36)

1. A device for controlling the movement of a door hingedly connected to a frame, comprising a member biassed to rotate in one direction, and retaining means operable to hold said member against the bias acting thereon, but which means can be released or overcome for the member to pivot, by virtue of the bias, in said one direction, the arrangement being such that, in use, the retaining means and said member are mounted at one of the door and the frame, and the member is normally held at rest by the retaining means, release of said retaining means or the overcoming thereof, freeing said member so that it directly or indirectly moves the door to a closed or open position, wherein the retaining means include a catch element which is movable by said member from a first to a second position upon movement of said member past it against said bias, the catch element thereafter returning to said first position and retaining the member against rotation in said one direction, and a retaining element engaging the catch element in said first and second positions and preventing it moving in a direction to release said retained member, the catch element, on release of or on the overcoming of the retaining element, moving in said direction to release the member.

2. A device as claimed in claim 1, wherein the movement of the catch element in the direction to release said member is guided by way of a guide surface of said catch element engaging a guide member.

3. A device as claimed in claim 2, wherein the retaining means include an electromagnet engageable by a keeper attached to a pivotally movable lever, part of which forms said retaining element, which engages the catch element when the electromagnet is energised to attract the keeper and which releases the catch element upon deenergisation or on said overcoming of said retaining element.

4. A device as claimed in claim 3, wherein the part of the lever forming said retaining element is a roller which engages a pressure button of the catch element when the electromagnet is energised.

5. A device as claimed in claim 4, wherein the catch elemerit is an elongate member having a shank and an enlarged head, the end of the shank remote from the head having said pressure button, and the head having an external surface against which the member engages when held by the catch element, and a slot therein defining said guide surface engageable by said guide member.

6. A device as claimed in claim 5, wherein the catch element is disposed on a baseplate having a straight longitudinally extending edge, the part of the catch element having said external surface projecting beyond said edge in said first position of the catch element and being movable substantially at right angles thereto towards said edge to said second position where the member moves past said catch element part from one side of said external surface to the other, the catch element being held against longitudinal movement relative to the backplate in the first and second positions but being movable longitudinally by said member when the roller is released, such longitudinal movement causing a guide member fixed relative to the baseplate to engage said guide surface and to move said part of the catch element towards said longitudinal edge in addition to its longitudinal movement produced by the member, thereby to release the member.

7. A device as claimed in either of claims 5 and 6, wherein the shank passes through a slot in a spacer block on the backplate to prevent removal of the catch element in a direction substantially normal to its length but to allow limited movement in that direction.

8. A device as claimed in any one of claims 5 to 7, wherein the head has a further external surface next to said member engaging surface which, in use, acts as a lead-in surface over which the member rides whilst moving said catch element from its first to its second position.

9. A device as claimed in any one of claims 5 to 8, wherein the catch element is symmetrical about a longitudinal centre line thereof.

10. A device as claimed in any one of the preceding claims, wherein the catch element is biassed by a biassing member to said first position to which it thus returns the catch element after movement to said second position.

11. A device as claimed in claim 7, wherein a further spacer block is provided on the baseplate and a door closer is carried by said spacer blocks and extends over part of the catch element, the door closer having extending from it a spindle to which said member, in the form of a catch plate, is secured for rotation therewith against said bias which is provided by the door closer.

12. A device as claimed in claim 11, wherein the spindle has a main arm freely rotatably received thereon, and a secondary arm is freely pivotally connected to a free end of the main arm at one of its ends, with its other end being pivotally attached to the other of the door and the frame, the main arm in one arrangement being securable to the catch plate to allow the doorto be held open, in use, upon retention of the catch plate, and in an alternative arrangement being releasable from the catch plate to allow the door to be free-swinging, in use, upon retention of the catch plate.

13. A device as claimed in claim 12, wherein the catch plate has a slot therein and the main arm has an aperture therein so that a bolt can be received through said aperture and said slot at a chosen part of said slot to secure the catch plate to the main arm for said door hold open arrangement, or alternatively the bolt can pass through the slot only and have secured thereon a spacer at one side of the main arm, so that the main arm can swing freely away from the spacer in said door free-swing arrangement.

14. A linkage mechanism for use in a device for controlling the movement of a door hingedly connected to a frame, comprising a spindle, a catch member connected to or integral with the spindle for rotation therewith, an arm carried by the spindle and freely rotatable thereon, the catch member and the arm having respective openings therein at least part of each of which can be aligned, and fixing means for passing through said aligned parts of the openings to secure the arm to the catch member, or for passing through said opening in the catch member only, at one side of the arm, so that the arm can move angularly away from the fixing means in one direction and engages the fixing means upon angular movement in the opposite direction.

15. A mechanism as claimed in claim 14, wherein one of the openings comprises one or more slots so that by rotation of the arm it is possible to align the other of the openings with a selected part of the or a slot, with the fixing means passing through the other of the openings and the or a slot to secure the arm to the catch member in a chosen relative orientation.

16. A mechanism as claimed in claim 14 or claim 15, wherein the underside of the catch member, which is remote from the arm, is grooved to receive a head of a bolt of the fixing means which passes through the catch member.

17. A mechanism as claimed in claim 16, wherein when the bolt passes through both the catch member and the arm, washers are received thereon between the catch member and the arm, and the arm and a nut secured on the end of the bolt, respective, whilst when the bolt passes through the catch member only, a spacer and the nut only are received on the bolt at the ungrooved side of the catch member.

18. A mechanism as claimed in any one of claims 15 to 17, wherein the opening in the arm is a through hole and a single slot is provided in the catch member, the slot being ofarcuateform and coinciding with an arc formed by the hole in the arm upon rotation of the arm over the catch member, so that when the fixing means passes through the catch member only it can be at a chosen position along the slot, at one side of the arm.

19. A mechanism as claimed in claim 18, wherein the slot is divided into three distinct sections by means of constrictions.

20. A mechanism as claimed in claim 19, wherein the catch member has a projecting part extending radially and aligned with the spindle and the centre section of said slot.

21. A mechanism as claimed in any one of claims 14to 20, wherein a secondary arm is freely pivotally connected to the end of said arm which is remote from the spindle.

22. A mechanism as claimed in claim 21, wherein the secondary arm is hollow so as slidably to receive and secure strip means for connection to the door or frame, itthus being possible to vary the length of the strip means received in the secondary arm as required.

23. A device for controlling the movement of a door hingedly connected to a frame, comprising a linkage mechanism as claimed in any one of claims 14 to 22, wherein the spindle is biassed to rotate in one direction together with said catch member, and retaining means are provided which are operable to hold the catch member, and thus the spindle, against said bias, but which can be released or overcome for said catch member to move angularly, by virtue of the bias, in said one direction, the arrangement being such that, in use, the retaining means and the spindle are mounted at one of the door and the frame, and the catch member is normally held at rest by the retaining means, release of said retaining means or the overcoming thereof, freeing said catch member so that, by way of said arm, it moves the door to an open or closed position.

24. A device as claimed in claim 23, wherein the retaining means include a catch element which is movable by said catch member from a first to a second position upon movement of said catch member past it against said bias, the catch element thereafter returning to said first position and retaining the catch member against rotation in said one direction, and a retaining element engaging the catch element in said first and second positions and preventing it moving in a direction to release said retained catch member, release of the catch element, on release of or on the overcoming of the retaining element, moving in said direction to release the catch member.

25. A device as claimed in claim 24, wherein the movement of the catch element in the direction to release said member is guided by way of a guide surface of said catch element engaging a guide member.

26. A device as claimed in claim 25, wherein the retaining means include an electromagnet engageable by a keeper attached to a pivotally movable lever, part of which forms said retaining element, which engages the catch element when the electromagnet is energised to attract the keeper and which releases the catch element upon deenergisation or on said overcoming of said retaining element.

27. A device as claimed in claim 26, wherein the part of the lever forming said retaining element is a roller which engages a pressure button of the catch element when the electromagnet is energised.

28. A device as claimed in claim 27, wherein the catch element is an elongate member having a shank and an enlarged head, the end of the shank remote from the head having said pressure button, and the head having an external surface against which the catch member engages when held by the catch element, and a slot therein defining said guide surface engageable by said guide member.

29. A device as claimed in claim 28, wherein the catch element is disposed on a baseplate having a straight longitudinally extending edge, the part of the catch element having said external surface projecting beyond said edge in said first position of the catch element and being movable substantially at right angles thereto towards said edge to said second position where the catch member moves past said catch element part from one side of said external surface to the other, the catch element being held against longitudinal movement relative to the backplate in the first and second positions but being movable longitudinally by said member when the roller is released, such longitudinal movement causing a guide memberfixed relative to the baseplate to engage said guide surface and to move said part of the catch element towards said longitudinal edge in addition to its longitudinal movement produced by the catch member, thereby to release the catch member.

30. A device as claimed in either of claims 28 and 29, wherein the shank passesthrough a slot in a spacer block on the backplate to prevent removal of the catch element in a direction substantially normal to its length but to allow limited movement in that direction.

31. A device as claimed in any one of claims 28 to 30, wherein the head has a further external surface nextto said catch member engaging surface which, in use, acts as a lead-in surface over which the catch member rides whilst moving said catch element from its first to its second position.

32. A device as claimed in any one of claims 28 to 31, wherein the catch element is symmetrical about a longitudinal centre line thereof.

33. A device as claimed in any one of the preceding claims, wherein the catch element is biassed by a biassing member to said first position to which it thus returns the catch element after movement to said second position.

34. A device as claimed in claim 30, wherein a further spacer block is provided on the baseplate and a door closer is carried by the spacer blocks and extends over part of the catch element, said spindle being connected to said door closer which provides said bias thereon.

35. A device for controlling the movement of a door hingedly connected to a frame, substantially as hereinbefore described with reference to and as shown in Figures 1 to 3 and 6 and 7, or Figure 11 of the accompanying drawings.

36. A linkage mechanism for use in a device for controlling the movement of a door hingedly connected to a frame, substantially as hereinbefore described with reference to and as shown in Figures 4 and 5 and Figures 8 to 10 of the accompanying drawings.