GB2439408A

GB2439408A - Alarm call point having a break pane comprising two separate regions linked by a frangible region

Info

Publication number: GB2439408A
Application number: GB0706925A
Authority: GB
Inventors: Wilhelm Weissgerber; Thomas Hanses; Sonja Tiedemann
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2006-04-10
Filing date: 2007-04-10
Publication date: 2007-12-27
Anticipated expiration: 2027-04-10
Also published as: CN101118686A; DE102006016803B4; GB2439408B; CN101118686B; DE102006016803A1; GB0706925D0

Abstract

A break pane 3 of plastics material for an alarm call point device 1 with at least two sub-regions 6, 7 and with at least one predetermined separating point 8, 9, 10 is disclosed. The predetermined separating point 8, 9, 10 extends at least in portions between the at least two sub-regions 6, 7. The predetermined separating point 6, 7 is formed so that the at least two sub-regions 6, 7 are separated from one another upon application of a predetermined force, such that the predetermined separating point 8, 9, 10 is formed so as to be only irreversibly separable. Also disclosed is an alarm call point housing comprising a break pane in which the break pane can be inserted into the closed call point housing from the outside and a method of forming a break pane comprising two different regions, each of a different material, wherein the two different regions are joined in a common injection mould.

Description

Description Title

Break pane of plastics material for an alarm call point device, alarm call point device with break pane and method for producing the break pane

Prior art

The invention relates to a break pane of plastics material for an alarm call point device, an alarm call point device and a method for producing the break pane.

Alarm call point devices are known from a great many fields of application. Thus devices of this kind are usually used as decentralised emergency call points, for example for the police, the fire brigade or the emergency doctor. Alarm call point devices with a housing which has a clear front pane are generally known. According to EN (European Standard) 54-11, the alarm call point devices are classified according to the type of alarm triggering. A first type relates to the direct triggering of the alarm, in which case the alarm is triggered by destroying or displacing the front pane or parts thereof. Where another type is concerned, a trigger element, for example a push button, has to be additionally actuated in order to trigger the alarm.

In the case of the latter construction glass panes are at present usually used as front panes. These glass panes are broken or pushed in by the person who wants to trigger an alarm in order to actuate the trigger element disposed behind. In spite of safety measures on the part of the manufacturer, the risk of injury through fragments. of the glass panes cannot be entirely ruled out.

In order to further reduce the risk of injury, the publication GB 2313614A discloses a breakable cover for an emergency monitoring device. This cover essentially consists of a reinforced special glass which has a linear section with a reduced material thickness. The cover also comprises a breaking device which is formed to introduce local force into the section with the reduced material thickness. When the cover is broken a break is induced in the region of the section by means of the breaking device and the reinforced special glass is as a result crumbled into small, harmless parts.

The publication NZ 330406, which constitutes the closest prior art, discloses a cover for an alarm call point device in the form of a two-part window. This window has a frame region, which is fastened to or in the alarm call point device, and an inner window part, which can be pushed out or knocked out by the action of force. The frame region and the window part are connected together by way of a positive connection which is constructed such that after use -i.e. after actuating the alarm call point device -the window part can be re-inserted in the frame region.

Disclosure of the invention

The invention relates to a break pane of plastics material having the features of Claim 1, an alarm call point device having the features of Claim 10 and a method for producing the break pane having the features of Claim 13. Preferred and/or advantageous embodiments of the invention are presented by the subclaims and the following description and/or the figures.

The break pane according to the invention is formed and/or adapted for an alarm call point device, in particular a manual fire alarm call point (preferably according to EN 54-11), a signal generator and/or a push button fire alarm call point. It consists completely and/or substantially completely of plastics material which is preferably clear and/or diaphanous or translucent and/or transparent. In less preferred embodiments the plastics material is opaque.

At least two sub-regions, i.e. surface sub-regions, are provided, these being separated from one another by at least one predetermined separating point. The at least two sub-regions are preferably completely separated from one another by the predetermined separating point, although a separation which only extends in portions between the at least two sub-regions is preferably also included in the scope of this invention. The predetermined separating point optionally divides the break pane into a plurality of segments or sub-regions. The predetermined separating point is preferably formed such that the at least two sub-regions are separated from one another as from a predetermined action of force, in particular when the break pane is subjected to a limit force and/or to a limit impulse which separates at least two sub-regions from one another. It is preferable to completely separate the at least two sub-regions, while an alternative structural implementation of the break pane lies in the at least two sub-regions preferably being largely separated along the predetermined separating point and in particular only being joined by remaining portions.

According to the invention, the predetermined separating point and/or sub-regions thereof are/is formed so as to be only and/or exclusively irreversibly and/or irreparably separable. Following separation of the predetermined separating point, the at least two sub-regions can in particular no longer be assembled such that the assembled break pane again corresponds identically with the original break pane and/or such that it can be confused with the latter. It is basically sufficient for this if one, a plurality of or all the sub-region(s) sustain in particular slight damage, so that reassembly of the break pane can be detected. The break pane is alternatively formed such that damage resulting upon separation is so serious that reassembly of the break pane is completely ruled out. As a further alternative, the predetermined separating point is formed in structural terms such that reassembly is impossible even when sub-regions are intact.

In this respect the invention is based on the consideration that the use of plastics material as base material for break panes is basically of advantage, as, in contrast to a glass material, the plastics material gives rise to a lower risk of injury, as required, for example, by EN 54-li. On the other hand, the glass material has the advantage that use of the alarm call point device cannot remain unnoticed, as a break pane of glass is irrevocably destroyed. However break panes of plastics material, as are known from the closest prior art, can be reassembled following use, so that the use can be concealed. According to the invention, in order to combine the advantages of break panes of plastics material and break panes of glass, it is proposed that break panes of plastics material be provided with predetermined separating points which are formed so as to be only and/or exclusively irreversibly separable.

In one preferred embodiment the predetermined separating point is formed as a region, in particular a line region, of the break pane with a reduced material thickness. A predetermined breaking point and/or a predetermined breaking line are/is in this way formed on account of a weakening of the cross section of the break pane. The weakening of the material thickness may be achieved, for example, through a V-shaped and/or U-shaped groove. However a weakening groove of this, kind can basically be of any desired shape.

As an alternative or in addition to this, the material thickness of the break pane varies along the path of the predetermined separating point. For example, the predetermined separating point may be in the form of a perforation line, in which case regions of thicker and thinner material thickness alternate with voids such as, e.g. perforation holes or regions, which are continuous through the break pane.

In a further structural alternative the at least two sub-regions interlock positively, in which case the positive engagement is preferably formed such that, as a result of separating the two sub-regions, the positive engagement regions are at least partly destroyed and/or the separated sub-regions can no longer be assembled to form the original break pane.

In a further preferred development of the invention the at least two sub-regions consist of different materials and are joined in a common injection mould. This production variant creates a break pane in the case of which the at least two sub-regions are connected together integrally and/or positively and so as only to be separable in a destructive manner. In this embodiment the at least two sub-regions are preferably made of a material mix, in which case the materials are selected such that they do not permanently join together when injection moulding in a common mould and can be separated from one another when the break pane is used by the predetermined action of force.

To summarise, the predetermined separating point can therefore be formed as a positive and/or non-positive and/or integral connection which can only be separated in a destructive manner and/or cannot be reassembled without damage following separation.

In one advantageous embodiment the predetermined separating point is formed as a line. The line may in this case be formed as an open line with two free ends or as a closed line and/or as a combination of open and closed lines.

Examples of closed lines are circles, ovals, polygons, rectangles, etc. The break pane preferably has a plurality of lines as the predetermined separating point, in which case the individual lines or line portions can also be formed differently with regard to the integral, non-positive and/or positive connection.

In a particularly advantageous embodiment the predetermined separating point comprises at least one open line, in which case the free ends of this line end at least at one side edge, in particular at a common side edge, of the break pane. The sub-region which is defined by the open line preferably. forms an edge piece in the break pane. The line path is U-shaped and/or V-shaped. This embodiment includes the advantageous possibility of easily removing the sub-region of the break pane which is defined by the open line following the action of force resulting in separation of the predetermined separating point, as the sub-region which is separated out is not retained by the remaining sub- region or sub-regions of the break pane. The legs of the U-or V-shaped line path are preferably formed so as to diverge towards the side edge, in particular such that removal slopes are formed by the line path on one side or both sides.

In an advantageous development of the invention the break pane has moulded-on fastening devices which are formed for fastening the break pane in the alarm call point device.

The break pane and the moulded-on fastening devices are in particular formed in one piece. The fastening devices are preferably designed in structural terms such that, after the break pane has been fastened in the alarm call point device, they can in particular only and/or exclusively be detached irreversibly and/or irreparably from outside. This also reflects the inventive concept of configuring the break pane such that undesirable manipulations of the break pane are ruled out and/or can be detected. The fastening devices are preferably formed as flexible and/or resilient moulded-on parts and may, for example, be in the form of snap hooks.

In particular in a continuation of the concept of easily removing from a or the alarm call point device a sub-region of the break pane which is separated by the action of force, in order, for example, to reach unobstructed a call button lying behind the break pane., a side edge of the break pane is optionally bevelled and/or rounded. In this respect the modification of the side edge is formed in structural terms so as to facilitate the removal of the break pane from the alarm call point device. A bevel angle relative to the top side and/or underside of the break pane of between 400 and 80 and/or between 100 and 150 is preferably used. In modified embodiments it is sufficient for just a sub-portion of a side edge to be bevelled, in particular a sub-portion which extends over a sub-region of the break pane.

A further subject matter of the invention relates to an alarm call point device with a break pane according to the preamble of Claim 1 and/or according to any one of Claims 1 to 9 and/or the preceding description, wherein the break pane can be inserted in the closed call point device from outside.

This further or supplementary inventive concept is based on the consideration that it is normally necessary, in order to replace destroyed break panes, to open the alarm call point device with a special key and insert a new break pane. This process is time-consuming and, moreover, the maintenance staff always have to carry the special key with them. As opposed to this, a proposal lies in the possibility of inserting the break pane from outside, i.e. with the alarm call point device closed, in which case the break pane is inserted in the housing in the alarm call point device from the outside. It is preferable to provide the possibility of also removing the remainder of a break pane which has been broken or pushed in without opening the alarm call point device. As already mentioned above, fastening preferably takes place by means of fastening devices, in particular snap hooks.

In order in particular to prevent manipulation by levering out the break pane by means of a screwdriver or similar, it is proposed that the break pane be configured and/or mounted flush with the alarm call point device or set back in the direction of the alarm call point device. A flush or set-back mounting system makes it impossible or more difficult for an unauthorised user to remove the break panel without irreversibly damaging this.

It is preferable to provide for separated sub-regions in the alarm call point device a removal aid which is formed as a bevel, for example, so that a separated sub-region of the break panel can easily be removed from the alarm call point device and/or automatically falls out and/or slides out of the alarm call point device. This removal device is preferably formed as a bevel which corresponds to the bevelled side edge and/or to the bevelled sub-portion and has in particular a corresponding bevel angle.

A further subject matter of the invention is a method having the features of Claim 13, wherein the at least two sub-regions are preferably injection moulded in the common injection mould or a second sub-region is injection moulded onto a first sub-region in the common injection mould.

Brief description of the drawings

Further features, advantages and the effect of the invention will emerge from the following description an.d the drawings of preferred embodiments. In the drawings: Fig. 1 shows a first embodiment of an alarm call point device according to the invention in a schematic 3D view from the front in an exploded representation; Fig. 2 shows the alarm call point device in Fig. 1 with inserted break panel; Figs. 3a to e show five different embodiments for a break pane for inserting in the alarm call point device in Fig. 1 or 2.

The same or corresponding parts are given the same reference characters in each case in the figures.

Embodiment(s) of the invention Figure 1 shows a manual fire alarm call point 1 as a first embodiment of an alarm call point device according to the invention in a schematic 3D representation. The manual fire alarm call point 1 is formed, for example, as type A or type B according to EN 54-11. The manual fire alarm call point 1 comprises a housing 2, in the front of which a break pane 3 can be inserted. The housing 2 and the break pane 3 are represented separate from one another in an exploded manner in the representation in Figure 1. In order to install the break pane 3, the housing 2 comprises a fastening frame 4, which has in the centre region a rectangular or square opening for installing the break pane 3.

The break pane 3 has at its side edges a total of six snap hooks 5 which are formed. for. fastening the break pane 3 in the fastening frame 4. The snap hooks 5 are moulded onto the break pane 3 and integrally connected to the latter.

Each snap hook 5 has a leg which projects perpendicularly to the rear from the underside of the break pane 3 and at the free end of which a second leg is disposed, this projecting therefrom in the shape of a V. The first and the second leg of the snap hooks 5 are in each case disposed such that, when the break pane is inserted in the fastening frame 4, these are resiliently pushed together and -after the break pane 3 has reached its end position in the fastening frame 4 -relax again, with the respective second leg being supported on the back or inside of the fastening frame 4.

The inner contour of the fastening frame 4 for installing the break pane 3 has webs on which the break pane 3 lies in the fitted state and which are discontinuous in the regions corresponding to the snap hooks 5. In order to fasten the break pane in the fastening frame 4, the break pane 3 is inserted in the housing 2 from outside, so that the break pane 3 is supported by the webs of the fastening frame 4 on one side and retained by the snapped-in snap hooks 5 on the other.

Figure 2 shows the manual fire alarm call point 1 in Figure 1 in the same representation, although in the assembled state and operable state. A trigger element, in particular a push button, for triggering a fire alarm is optionally disposed behind the break pane 3. The break pane 3 is formed from plastics material and so as to be clear, or at least light-transmitting, so that trigger elements, characters or optical warning devices positioned behind the break pane 3 can be seen from outside, even when the housing is closed. The fastening frame 4 can basically also be formed from plastics material, although in alternative, in particular highly stable embodiments the fastening frame is formed from metal. The housing 2 of the manual fire alarm call point 1 can optionally be opened by a special key in order to enable maintenance and/or inspection work to be carried out.

The outer top side of the break pane 3 is preferably flush with the outside of the fastening frame 4, in particular such that no application point for levering out the pane by means of a screwdriver, for example, is provided. In alternative embodiments the break pane 3 may also be offset inwards with respect to the outside of the fastening frame 4.

As can be seen from the representations of Figure 1 and Figure 2, the break pane 3 can be inserted in the manual fire alarm call point 1 without opening the housing 2.

After actuating or using the manual fire alarm call point 1, i.e. after breaking the break pane 3, this can likewise be pulled out or broken out to the front without opening the housing 2. It is therefore unnecessary to open the housing 2 when inserting the break pane 3 and/or when removing the actuated break panes 3.

Figure 3a shows a first embodiment of a break pane 3 wherein the snap hooks 5 have not been included in the representation for reasons of clarity, as in the case of the following Figures 3b to e.

The break pane 3 comprises an outer sub-region 6 and an inner sub-region 7 which are separated from one another by a predetermined separating line 8. The outer sub-region is formed as a rectangular or square plastics window which bears the inner sub-region 7 in the centre, separated by the predetermined separating line 8. In the plan view in Figure 3a the inner sub-region 7 is formed as an oval or a circular inner sub-region 7. The break pane 3 is inserted in the housing 2 of the manual fire alarm call point 1 for use.

In the event of an alarm, a user pushes or strikes the inner sub-region 7, resulting in the destruction of the connection between the inner sub-region 7 and the outer sub-region 6 via the predetermined separating point 8 and in the inner sub-region 7 falling out. In this respect the use of the plastics material as the material for the break pane 3 ensures that no splinters which can constitute a risk of injury are produced. Moreover, the use of a predetermined separating line 8 ensures that there is no possibility of carrying out manipulations enabling the inner sub-region 7 to be re-inserted in the outer sub-region 6 without these manipulations being immediately detectable on account of the damaged predetermined separating line 8.

There are various possibilities for the technical implementation of the predetermined separating line 8.

Firstly, this predetermined separating line 8 can be formed as a predetermined breaking line by introducing a weakening of the pane cross section into the break pane 8 during the manufacturing process. This weakening may be achieved, for example, through a V-or U-shaped groove.

Secondly, the outer sub-region 6 and the inner sub-region 7 can be connected together by way of a positive connection which is in particular constructed such that the mechanical interfaces of the positive connection are destroyed at least in portions when the break pane 3 is broken or pushed in.

A further possibility lies in producing the outer sub-region 6 and the inner sub-region 7 from different materials which do not permanently join together when injection moulding in a common mould, in which case this connection region then represents the predetermined separating line 8 or predetermined breaking line.

Figure 3b shows once again the break pane 3 in Figure 3a, with the predetermined separating line 8 being formed as a circular, V-shaped groove.

Figure 3c shows a further development of the break pane in Figure 3, with additional predetermined separating lines 9 and 10 being provided. The predetermined separating line 9 has a rectangular path with four side portions disposed at a right angle to one another, the four side portions being disposed parallel to the side edges of the break pane 3 and surrounding the predetermined separating line 8 at a spacing like a frame. Starting from the corner regions of the rectangular predetermined separating line 9, four predetermined separating lines 10 extend radially into the centre of the break pane 3 and connect the corner regions of the rectangular predetermined separating line 9 to the predetermined separating line 8. Upon actuating this break pane 3, a total of five individual parts are separated or broken out of the outer sub-region 6. The predetermined separating lines 8, 9 and 10 may in this case be formed according to one of the previously described alternatives.

A mixture of these alternatives also represents a possible embodiment.

Figure 3d shows a further embodiment for a break pane 3 according to the invention which consists of two sub-regions, namely a portal region 11 and a door region 12. A predetermined separating line 13 turned over in the shape of a U is disposed between the portal region 11 and the door region 12, the legs of the U being formed so as to diverge towards their free ends. The predetermined separating line 13 is formed in a manner similar to that of the predetermined separating lines 8, 9 or 10, with the difference that the ends of the predetermined separating line 13 are disposed at the bottom side edge of the break pane 3 and/or pass through. This design enables the door region 12 in the representation of Figure 3d to fall downwards out of the portal region 11 when the break pane 3 is actuated and the predetermined separating line 13 therefore separated. Particularly when the door region 12 is not to fall out perpendicularly downwards, but should instead fall out of the housing 2 when the break pane 3 is in the fitted state, a bevel 14 is optionally disposed at the bottom side edge of the break pane 3, in particular at the free side edge of the door region 12, which bevel, through its inclination, makes it easier for the door region 12 to slide out.

Figure 3e shows a further development of the break pane 3 in Figure 3d, with the portal region 11 being separated by two predetermined separating lines 15a and 15b. The predetermined separating lines 15a,. b in each case extend from an outer corner of the portal region 11 to the predetermined separating line 13, which they meet in the curved top region of the predetermined separating line 13.

The predetermined separating lines 15a and 15b are axially symmetrical relative to one another. Firstly, in this construction the door region 12 in the representation 3e can fall out downwards. Secondly, the remaining portal region 11 disintegrates into three further sub-regions which can be removed from the housing 2 of the fire alarm call point 1 independently of one another, so that it becomes easier to remove the used break pane from the alarm call point device when the housing is closed.

Claims

Claims: 1. Break pane (.3) of plastics material for an alarm call point

device (1) with at least two sub-regions (6, 7, 11, 12) and with at least one predetermined separating point (8, 9, 10, 13) wherein the predetermined separating point (8, 9, 10, 13) extends at least in portions between the at least two sub-regions (6, 7, 11, 12) and wherein the predetermined separating point (6, 7, 11, 12) is formed so that the at least two sub-regions (6, 7, 11, 12) are separated from one another as from a predetermined action of force, characterised in that the predetermined separating point (8, 9, 10, 13) is formed so as to be only irreversibly separable.

2. Break pane (3) according to Claim 1, characterised in that the predetermined separating point (8, 9, 10, 13) is formed as a region of the break pane (3) with a reduced material thickness.

3. Break pane (3) according to either of the preceding Claims 1 arid 2, characterised in that the material thickness of the break pane (3) varies along the path of the predetermined separating point (8, 9, 10, 13).

4. Break pane (3) according to any one of the preceding Claims, characterised in that the at least two sub-.

regions (6, 7, 11, 12) interlock positively.

5. Break pane (3) according to any one of the preceding Claims, characterised in that the at least two sub-regions (6, 7, 11, 12) consist of different material and are joined in a common injection mould.

6. Break pane (3) according to any one of the preceding Claims, characterised in that the predetermined separating point (8, 9, 10, 13) is formed as at least one open line and/or as at least one closed line and/or as a combination of open and closed lines.

7. Break pane (3) according to Claim 6, characterised in that the or one of the open line(s) ends with one or both end(s) at a side edge of the break pane and/or at a further line.

8. Break pane (3) according to any one of the preceding Claims, characterised by moulded-on fastening devices (5) which are formed for fastening the break pane in an alarm call point device.

9. Break pane (3) according to any one of the preceding Claims, characterised in that at least one side edge of the break pane (6) or a sub-portion of a side edge which extends over a sub-region (12) of the break pane is bevelled.

10. Alarm call point device (1) with a housing (2) which is to be opened, characterised by a break pane (3) according to the preamble of Claim 1 and/or according to any one of the preceding Claims, wherein the break pane (3) can he inserted in the closed housing (2) from outside.

11. Alarm call point device (1) according to Claim 10, characterised in that the break pane (3) can be mounted and/or is mounted flush with the housing (2) of the alarm call point device or in particular set back in the direction of the housing.

12. Alarm call point device according to either of Claims and 11, characterised in that the alarm call point device has a bevel which corresponds to the bevelled side edge or to the bevelled sub-portion, so that a removal aid for a sub-region of the break pane which is separated by the action of force is formed.

13. Method for producing the break pane according to any one of Claims 1 to 10, wherein the at least two sub-regions consist of different materials, wherein the at least two sub-regions are joined in a common injection mould.

14. Break pane substantially as hereinbefore described with reference to the accompanying drawings.

15. Alarm call point device substantially as hereinbefore described with reference to the accompanying drawings.

16. Method for producing a break pane, substantially as hereinbefore described with reference to the accompanying drawings.