GB2351320A - Emergency exit device - Google Patents

Abstract

A method of assembling an emergency exit device for a door the device comprising a body (10), having an inner face and an inner side wall therearound, first and second latch bolt actuating members (12,13) for movement in opposite directions in the body between extended and retracted positions, operating means (21) for exterior mounting on the body, an element (58) for angular movement in the body at the side of the actuating members remote from said body inner face, to transmit its angular movement to at least one of the actuating members, and resilient means (48) acting between the first and second actuating members. The method comprising assembling said actuating members (12,13), operating means (21) and said element (58), and thereafter inserting said resilient means (48) through an opening (46) defined in the actuating member (12), so as to be disposed between the inner face of the body and the actuating members, and to act to bias the actuating members apart.

Description

2351320 EMERGENCY EXIT DEVICE This invention relates to an emergency exit

device, intended to be fitted at a door, in which actuation of an operating member effects retraction of upper and lower vertical rods from their respective associated sockets at the top and bottom of the door. The rods extend into a casing at which the operating member is pivotally mounted. A horizontal bar normally extends across the centre of the door, one end of the horizontal bar being attached to the operating member, and the other end being pivotally attached to a further casing attached to the door.

With such an emergency exit device, often referred to as a panic bolt, the casings, rods and horizontal bar are attached to the inside of the door, in use, whilst at the outside there can be attached to the door an operating member with associated locking means, so as to allow opening of the door from the outside by a keyholder, i.e. an authorised person only. Connection between the outside operating member and the casing at which the inside operating member is mounted is by means of a spindle or equivalent extending through the door into the casing at the inside of the door, where it is arranged to cause retraction of the vertical bars when the outside operating member is actuated.

An object of the invention is to provide an emergency exit device in an ved manner.

According to the invention, there is provided a method of assembling an emergency exit device for a door, the device having a body for attachment to one side of a door, the body having an inner face and an inner side wall therearound, first and second latch bolt actuating members movable in opposite directions in the body between extended and retracted positions, operating means mounted exteriorly on the body, an element mounted for angular movement in the body at the side of the actuating members remote from said body inner face, to transmit its angular movement to at least one of the actuating members, and resilient means acting between the first and second actuating members, the method comprising assembling said actuating members, operating means and said element and thereafter inserting said resilient means through an opening defined either in at least one actuating member, or between at least one actuating member and said inner side wall, so as to be disposed between the inner face and the actuating members, and to act between said actuating members to bias them apart.

Preferably the resilient means is a coiled compression spring, and conveniently it is inserted through an opening at an edge of one of the actuating members adjacent said inner wall. Desirably the spring is seated at its ends on respective lugs of the actuating members directed towards said inner face of the body.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure I is a schematic rear view of the inside of an emergency exit device assembled by the method of the invention; Figure 2 is a schematic side sectional view of a body of the device of Figure 1, with an operating handle shown pivotally attached thereto; Figure 3 is a front view of the operating handle; Figures 4 and 5 are opposite side views respectively of the operating handle; Figures 6 and 7 are a rear plan view and a side view respectively of an upper latch bolt actuating plate of the device of Figure 1; Figures 8 and 9 are a rear plan view and a side view respectively of a lower latch bolt actuating plate of the device of Figure 1; Figures 10 to 12 are a rear plan view, a front plan view and a side view respectively of a follower of the device of Figure 1; and Figures 13 and 14 are respectively a plan view and a side view of a follower cam of the Figure 1 device.

The emergency exit device. shown assembled in Figure 1 is, in several respects, of a form conventional with panic bolts. The device comprises a body case 10 which is substantially rectangular in plan and is open at its rear, as viewed in Figure 1, normally being closed, by a rear cover (not shown). The interior of the case 10 is open, and is provided with bosses for the reception of fixing screws from the front of the case into one side of the door at which the device is intended to be fitted. The case 10 is intended to be fitted, in use, at the inside surface of the door, with optionally an associated operating means being intended to be fitted at the opposite side of the door, as will be described, so as to allow for actuation of the device from the outside.

As shown in Figure 1, the device includes upper and lower latch bolt actuating members 12, 13 respectively. Each actuating member is in the general form of a plate, the members having respective elongated integral strip parts 14, 15 at their ends, these strip parts extending out of opposite ends of the body case 10 at respective openings 16, 17 through the respective upper and lower parts of the inner side wall 18 which surrounds an inner wall 19 of the body case. As shown in Figure 2, the body case is extended forwardly and outwardly approximately at its centre to provide a pivot 20 for pivotally mounting an operating handle 21, for actuation exteriorly of the body case 10, at the front of the device. As also shown in Figure 2, the inner wall 19 is provided with a central spigot 22 just below the position at which the operating handle 21 is mounted.

As will be more fully described, this spigot rotationally mounts a follower 23 which itself carries, for limited angular movement relative thereto, a follower cam 24.

A part of the operating handle 21 extends through a common opening defined in overlapping parts of the members 12, 13, and, as will be described, this generally engages the member 13, in use, to cause it to retract into the body case 10. Respective opposite ends of the follower 23 have downturned pegs, as will be described, these being received in respective slots in the actuating members. As a result, the inwards retraction of the actuating member 13 causes angular movement of the follower 23, which in turn causes retraction of the actuating member 12 into the body case, and in this way actuation of the operating handle in a downwards direction effects retraction of the latch bolts which are, in use, connected to the actuating members 12, 13 in any conventional form.

In order to prevent unauthorised entry through the door from the outside, it is necessary that in the extended position of the latch bolts any force which may be applied to cause the bolts to retract must be resisted, and with panic bolts in general there is normally some form of deadlocking to prevent retraction of the bars by lifting them out of their respective upper and lower sockets at the top and bottom of the door. The device is thus provided with this deadlocking. The invention described herein is, however, concerned with a convenient means of assembling the device, in particular in relation to biasing means which act between the two actuating members, so as automatically to return these members to their extended positions once operating means at either side of the door have been released.

Having described the mechanism generally, details of the various components will now be described with reference to the Figures.

The operating handle 21, shown in detail in Figures 3 to 5, has a main body part 25 in the general form of a rectangular pad having a flat front surface 26. At the lower free end of the body part 25 there is through opening 27 extending parallel to the shorter sides of the part 25, the opening being of generally rectangular form but with arcuate ends to receive, in use, one end of a conventional panic bolt operating bar which extends across the centre of the inside of the door, in use, and is pivotally connected at its opposite end to a further casing attached to the inner door surface. Accordingly in use it is possible to actuate the emergency exit device from the inner side of the door by applying force to the operating bar which thereby pivots and forces the main body part 25 downwardly and inwardly towards the inner door surface.

As previously mentioned, the operating handle 21 is Pivotally mounted at a forwardly extended front part of the body case 10, shown in Figure 2, and this pivot 20 is provided by a pivot pin passing through a circular opening 28 in a junction part 29 of the operating handle 21 at the end of the main body part 25 remote from the opening 27.

As shown best in Figures 4 and 5 this junction part is formed as part of a cylinder with its part-cylindrical surface 30 mating with a corresponding surface of the body case to allow the downwards and inwards actuating movement referred to above about said aforementioned pivot pin.

Extending radially outwardly from the junction part 29, and at an angle of, for example, approximately 123 from a central plane of the body part 25 is an arm 31 of the operating handle, this, like the junction part 29, being of much reduced width as compared to the width of the body part 25, but also lying centrally thereof, as shown in Figure 3. The arm 31 has a flat upper surface and parallel opposite side surfaces normal to said top surface. Ile width of the arm is reduced along its length, terminating in a head 32 at its ftee end. The upper surface of the head is formed by part of an upwardly angled flat surface 33 extending from the main part of the arm, this surface 33 terminating at an arcuate surface 34 around the upper front end of the head. 'ne surface 34 leads to a slightly convexly curved front surface 35 which extends to the bottom of the body where a flat undersurface 36 is joined to a flat rear surface 37 which extends to the underside of the main part of the arm.

As shown best in Figures 1 and 5, part of this head is cut away at one side for just over half of its width, the cutting away producing an undersurface 38 substantially parallel to but raised above the undersurface 36, and a front surface 38 which is similar form to, but cut back from the front surfaces 34 and 35. This cutting away forms the uncut part of the head as a downwards projection which, as will be described, engages with the follower 23 to effect deadlocking of the emergency exit device, in use.

The upper latch bolt actuating member 12 shown in Figure 6, is, as previously mentioned, of flat plate-like form having a main body part from one end of which the strip part 14 extends centrally longitudinally. Within the member 12 is a central longitudinal opening 40 which is arranged symmetrically about the longitudinal centre line of the member having an upper part of rectangular form with parallel sides 41, 42 respectively, and a lower part of slightly greater width with parallel sides 43, 44, and a rounded closed end which terminates just short of the end of the plate remote from the strip part 14. At a longitudinal position approximately half way along the lower part of the opening defined by the sides 43, 44, is a tr-amerse slot 45 which extends normally inwards from the right hand edge of the plate as viewed in Figure 6. Similarly a verse slot 46 extends inwardly from the opposite edge of the plate at a position adjacent the end of the upper part of the opening 40. In each case the slot has parallel sides normal to the longitudinal extent of the plate. Moreover, the edge of the plate in which the slot 46 is produced, is cut away from a position just slightly below said slot 46, to the lower end of said edge. As will be explained, this is to allow passage of a peg on the follower 23 when the follower is angularly moved by the actuating member 13. At the upper end of the body part of the plate disposed just above the slot 46, part of the plate is turned through 90 to provide a lug 47 normal to the plane of the plate and extending in a direction which, in use, is inwardly of the body case 10 towards the inner wall 19 thereof. As will be explained, the lug 47 acts in use as an abutment for one end of a coiled compression spring 48, shown in Figure 1, which is inserted on assembly through the slot 46 and serves to bias the two latch bolt actuating members apart.

The lower latch bolt actuating member 13 is, like the member 12, of flat plate-like form. Moreover it has a longitudinally disposed central opening 49 therein, the upper part of which is rectangular with parallel sides 50, 51 respectively, and the lower part of which is of substantially the same form as the lower part of the opening 40, having parallel sides 52, 53 respectively and a rounded closed end. The upper part of the slot is, however, somewhat narrower than the lower part, in the same way as with slot 40 of the plate 12.

In use, when disposed in the body case 10, the lower part of the member 12 and the upper part of the member 13 lie in respective adjacent planes and overlap, with the lower member 13 outermost in the casing, so that the lower parts of the two openings 40, 49 respectively form a common opening through the composite arrangement of the two actuating members as they slide in opposite directions in the body case.

9- In the left hand edge of the member 13, as viewed in Figure 8, a transverse slot 54 extends inwardly normal to the longitudinal centre of the member, slot 54 substantially corresponding in form to the slot 45 in the plate 12, but being in the opposite edge thereto when the plates are disposed together in the body case. The opposite edge of the actuating member 13 has a slot 55 of considerable extent formed therein, this corresponding to the cutting away described with the actuating member 12 in order to allow for angular movement of the follower, and the slot 55 is provided for the same purpose in relation to a second peg of the follower. At the upper end of the opening 49, a tag is bent out of the plane of the plate to form a lug 56, normal to said plane and extending outwardly away from the inner wall 19 of the case 10, in use, when the actuating member 13 is received in said case. A further lug 57 is formed out of the plane of the plate by being bent through W in the opposite direction to the lug 56, this being at the said edge of the plate at which the transverse slot 54 is formed. The lug 57 is disposed below slot 54 and provides a lower abutment for the spring 48 referred to above. At the bottom of the main body part of the member 13 is the strip portion 15 disposed centrally of the plate and extending longitudinally therefrom.

T'he follower 23 shown in Figures 10 to 12 has a generally cylindrical body part 58 from one side of which extends a central boss 59 which has a cylindrical external surface. The diameter of this boss 59 is such that it can be fitted into the spigot 22 in a rotational manner. At each side of a central longitudinal plane normally through the part 58, the periphery of the part is formed with two sloping flat surfaces 60, 61 respectively which join at an actuate surface 62 struck around the axis of the boss 59. In this way the follower is formed with a pair of generally radial arms 63, 64. At the same side of the body part 58 as the boss 59, and at the respective ends of the arms are formed respective pegs 65, 66 extending normally from said side of the part 5 8. The surface of each peg is configurated, as shown in Figure 11, to provide an appropriate force transmitting face for engagement with one of the actuating members, and conveniently, as shown in Figure 11, the surface can include several actuate surface portions. As shown in Figure 12, the peg 66 is shorter than the peg 65.

At the surface of the body part 58 opposite to that from which the boss 59 extends, a section is cut away, this being shown by hatching in Figure 10. In particular to one side of the central boss 59, the arcuate peripheral surfhee of the body part 58 is cut away to provide a notch 67 sized to receive therein the projection formed at the end of the head 32, in the manner shown in Figure 1, to produce the deadlocldng previously mentioned in respect of the follower 23 and operating handle 21. With the projecting part of the head received in the notch 67 the adjacent part of the head formed by the cutting away mentioned is clear of the outer periphery of the follower. As can be seen from Figure 10, the recess formed in the one side of the body part 58 includes an initial arcuate part adjacent the notch 67, and then a straight part of the periphery of the follower 23.

An opening 68 extends axially through the boss 59 and the remainder of the follower, this opening 68 having the cross section shown in Figures 10 and 11, namely in the form of a square with convex sides. This form is obtained by drawing two squares on top of each other with one square offset to the other by an angle of approximately 30', with the squares still having a common centre.

The follower cam 24 shown in Figures 13 and 14 is in the form of a plate which has a central body part 69 of generally circular shape, as shown in Figure 13. Extending from the circumference of the circle is a generally radial, rectangular tail 70, and extending generally in the opposite diametrical direction from the circumference of the circular part is an ear 71 formed with a flat radial surface 72 which is joined to the circular periphery of part 69 by a pair of arcuate surfaces 73, 74 respectively, the surface 73 being an arc struck about the centre of the circular part 69. Extending centrally through the part 69 is a square opening 75 which corresponds to one of the squares referred to in determining the shape of the opening 68.

The shape of the follower cam 24 is such that it can be received in the recess in the follower 23 formed by the cutting away indicated by the hatched area in Figure 10, with the respective central axes of the follower 23 and follower cam 24 coincident. This allows relative lost motion between the two components to be taken up by restricted angular rotational movement of the follower cam in its recess, the surface 72 moving from engagement with a radial surface 76 at the edge of the recess in follower cam 24 towards the notch 67. The actual extent of the angular movement is governed by opposite sides of the tail 70 engaging spaced abutment surfaces extending inwards from the periphery of the follower cam 24 at the opposite peripheral side thereof from tha - t containing the notch 67. The abutment surfaces are spaced apart angularly by a greater extent that the width of the tail, said tail moving angularly upon angular movement of the follower cam.

a With the components having now been described, assembly of these to form the emergency exit device of the invention will now be described, making use, in particular, of Figures I and 2.

Firstly with the body case empty and open to its rear, the upper latch bolt actuating member 12 is inserted into the case and aligned to the top of the case with its strip part 14 extending upwardly through the end opening 16. The lower latch bolt actuating member 16 is then similarly inserted and aligned to the bottom of the case, with its strip part 15 extending downwardly through the end opening 17. With the actuating members so disposed, in an overlapping relationship, there is a common opening therethrough as previously described, by way of the overlapping of the central openings 40 and 49 in said members. The operating handle 21 is then brought up to the outer front part of the body case 10 and its arm is inserted through an opening in the front of the case, so that the handle is pivotally connected thereat as previously described. This engagement causes the arm to extend into the interior of the body case 10 so that its head protrudes beyond the lower actuating member 13.

The follower 23 is then engaged in place by passing its boss 59 through the common opening defined by the two actuating members so that the boss is received in the spigot 22 for rotation in the body case. The engagement of the follower is such that the two pegs 65 and 66 extend downwards into the slots 45 and 54 respectively in the upper and lower actuating members 12, 13, the peg 65 being longer so as to extend to the member 12 which is further inwards than the member 13. The engagement of the pegs in said slots is as shown substantially in Figure 1, when the actuating members are in their fully extended positions at the top and bottom of the body case respectively. In other words the peg 65 is in engagement with the upper and lower surfaces of the slot 45, whereas although the upper surface of peg 66 engages the upper surface of slot 54, the lower surface of the peg 66 is spaced upwardly from the lower surface of the slot 54 so as to define a degree of lost motion between the actuating member 13 and the follower 23, for a purpose to be described. With the follower in this disposition, it can be seen from Figure 1 that the notch 67 is disposed substantially vertically upright in alignment with the left-hand side of the common opening defined by the members 12 and 13. In fact as described, the arrangement is such that the projection formed as part of the head 32 is disposed so as to project into said notch 67, substantially as shown in Figure 1, with the cut away part of the head 23 at its side being clear of the follower, as previously mentioned.

Next the follower cam 24 is inserted into the recess formed in the outer surface of the follower, so that the arcuate surface 74 bears against the projection formed at the head 32.

Finally the spring 48, is. inserted thrungh the slot 46 in the upper latch boltactuating member 12. This spring engages at its upper and lower ends with the lugs 47 and 57 respectively, so that as a result the two plates are sprung in opposing directions, thereby keeping the vertical latch bolts fully extended in the locking position when the mechanism is at rest.

This method of assembly of the invention is particularly advantageous in that the mechanism can be assembled easily without any of the components being under tension, the spring being inserted as the last major assembly operation through the specially provided slot 46, even though the spring, after assembly, is at a much lower level in the case, when considered from the rear as shown in Figure 1.

The device is also considered to be particularly convenient in utilising a minimum number of components. As described, the total mechanism for the device at one side of the door comprises merely the body case, the operating handle, the upper and lower actuating members, the follower, the follower cam and the spring. The only additional components, which are incidental, would be the rear case cover, screws, the upper and lower latch bolts and bar guides. Thus both from the manufacturing and assembly standpoints, the device is particularly cost effective.

As described in the introduction, panic bolts of this general kind require a deadlocking device to prevent retraction of the latch bolts until either the horizontal crossbar or a through-door spindle at the opposite side of the door is operated. In known panic bolts, various methods are employed to achieve this deadlocking arrangement, these normally requiring a number of coupling components and often additional springs. The present invention, in at least one aspect thereof, achieves this deadlocking action particularly conveniently by utilising direct engagement between die operating handle and the follower. As far as the outer side of the door is concerned, the only additional component employed is the cam follower. Accordingly the device has a simple mechanism which is thus lower in cost to manufacture.

t. 1.

-is- Considering firstly operation of the device at the inside of a door, ag referring to the schematic assembly view of Figure 1, the first action would be the application of pressure in a generally forwards direction to the operating handle 21 by actuation of the horizontal crossbar normally attached thereto, as previously described. Actuation of the horizontal crossbar causes pivoting of the operating handle 21 which thus moves inwardly and downwardly towards the front face of the body case 10. This pivoting causes an upwards angular movement of the head 32, and in particular begins to lift the projecting part of the head out of the notch 67. In one arrangement of the invention, the upper curved surface 34 of the head can engage directly upon the lug 56 of the lower actuating member 13. With this arrangement the very first movement of the head will be transmitted through the lug 56 to the remainder of the lower actuating member 13 which is thus driven upwards in the body case. However in an alternative arrangement there could be a free space between the surface 34 of the head and the closed end of the opening 49 in the lower actuating member 13, so that initially as the operating member is actuated the upper surface 34 of the head moves angularly for a certain distance before it engages the lower actuating member 13 and drives it upwards.

However in either event the projecting par t of the head has moved clear of the notch 67 by the time that the lower surface of the slot 54 engages the lower surface of the peg 66 upon the member 13 being driven upwardly by the handle 21. Accordingly by the time the lower member 13 engages the follower, the follower itself is free to move angularly about its mounting spigot 22 in the body. It will be appreciated that it would be possible to allow for all of the lost motion required to be taken up by the movement of the head relative to the lower actuating member 13 so that the head did not contact this member and begin to drive it until the projecting part of the head was clear of the notch 67. In this case the peg 66 could always be in engagement with the lower surface of the slot 54. Alternatively the surface 34 of head 32 could be in engagement with the end of the slot 49 in the position shown in Figure 1, so that upwards driving of the lower plate would begin as soon as the operating member is actuated. In this case all the lost motion would be required between the lower surface of the slot 54 and the peg 66, this being provided by a suitably increased spacing. Finally of course, the lost motion required could be a combination of the two possibilities referred to.

In any event as the lower actuating member is driven upwardly, the consequent angular movement, in a clockwise direction as viewed in Figure 1, of the follower causes its peg 65 to drive the upper actuating member downwardly, by virtue of the engagement of the peg 65 on the lower surface of the slot 45. Upon fall permitted angular movement of the follower 23, the top and bottom latch bolts are fully retracted, so that the door can then be opened from the inside. Upon release of the force on the horizontal crossbar or on the operating handle 21 directly, the device returns to its rest position shown in Figure 1 by virtue of the force of the spring 48 which acts between the members 12 and 13 to return them to their fully extended positions, the projecting part of the body 32 at the end of the arm 31 again being received in the notch 67, again by virtue of spring bias on the operating handle, for example additionally at the area of the pivot 20, if required. Figure 1 shows a spring 77 for preventing unauthorised operation by lifting the bottom bolt so as to cause the handle to fall under gravity.

As described, this form of panic bolt is often used in conjunction with release operating means at the exterior of the door, so that, for example, an authorised 'keyholder' can gain access from outside. This mechanism attached to the outer side of the door would normally employ some form of lock together with an operating handle which, for example, includes a connecting barlspindle which extends through the door to extend through the follower cam and engage with the follower.

With the arrangement shown in Figure 1, it is intended that the connecting bar is of square cross-section, corresponding to the shape and size of the opening 75 in the follower cam. The follower cam is disposed in the follower so that there is lost motion between the two components by virtue of the square-shaped opening 75 being 'out of alignment' with either of the two squares which, as previously mentioned, are relatively rotated to form the shape of the configurated opening 68. As a result of theoffsetting by 30 of the two square shaped openings through the follower, the connecting bar which engages the follower cam without any relative rotation being possible can rotate through the 301 angle relative to the follower without angularly moving it. 11fis lost motion which allows the follower cam to rotate through a certain angle relative to the follower is necessary in order to release the engagement of the projection of the head of the arm 31 from the notch 67 in order then allow the connecting bar to rotate the follower 23.

The connecting bar passes through the follower cam before entering the follower, with, as described, the follower cam having no provision for lost motion relative to said bar. Consequently when the connecting bar is rotated from the exterior of the door, the follower cam immediately rotates. The surface 74 engages with the undersurface 36 of the head thereby forcing the head upwardly out of engagement with the notch 67 before the connecting bar picks up a bearing surface defined within the configurated opening 68 of the follower itself. Once the connecting bar has orientated itself within the opening 68 so as to move the follower angularly with it, further rotation of the connecting bar consequentially angularly moves the follower resulting in the previously described upwards driving of the lower actuating member 13 and the downwards driving of the upper actuating member 12, thereby resulting in retraction of the upper and lower latch bolts.

Thus in summary it can be seem that deadlocking of the mechanism is achieved by the engagement of the operating handle with the follower, removal of this deadlocking, in the case of panic exit, being allowed for by creating lost motion in the movement of the top and bottom plates. In the case of normal ingress, where a cylinder or handle is rotated on the outer side of the door, removal of the deadlocking is achieved by the design of the follower opening which allows lost motion between the follower and the connecting barlspindle, this lost motion allowing disengagement of the operating harKUe 21 by means of the follower cam.

Instead of the follower driving the upper plate, it could of course be arranged to drive the lower plate.

Claims (5)

1. A method of assembling an emergency exit device for a door, the device having a body for attachment to one side of the door, the body having an inner face and an inner side wall therearound, first and second latch bolt actuating members movable in opposite directions in the body between extended and retracted positions, operating means mounted exteriorly on the body, an element mounted for angular movement in the body at the side of the actuating members remote from said body inner face, to transmit its angular movement to at least one of the actuating members, and resilient means acting between the first and second actuating members, the method comprising assembling said actuating members, operating means and said element and thereafter inserting said resilient means through an opening defined either in at least one actuating member, or between at least one actuating member and said inner side wall, so as to be disposed between the inner face and the actuating members, and to act between said actuating members to bias them aparL
2. 2. A method as claimed in Claim 1, wherein the resilient means is a coiled compression spring.
3. 3. A method as claimed in Claim 2, wherein the spring is inserted through an opening at an edge of one of the actuating members adjacent said inner side wall.
4. 4. A method as claimed in Claim 2 or Claim 3, wherein the spring is seated at its ends on respective lugs at the actuating members directed towards said inner face of the body.
5. 5. A method of assembling an emergency exit device for a door, substantially as hereinbefore described.