GB2366451A

GB2366451A - A membrane-type manual tripping device

Info

Publication number: GB2366451A
Application number: GB0121508A
Authority: GB
Inventors: Didier Lair; Manuel Francisco; Philippe Geneste
Original assignee: Legrand SNC
Current assignee: Legrand SNC
Priority date: 2000-09-05
Filing date: 2001-09-05
Publication date: 2002-03-06
Anticipated expiration: 2021-09-05
Also published as: GB0121508D0; DE10143254B4; FR2813705B1; GB2366451A8; FR2813705A1; GB2366451B8; DE10143254A1; GB2366451B

Abstract

A membrane-type manual tripping device includes a case in which are disposed an actuator member and a plate 30 elastically deformable between two stable positions, disposed above said actuator member and preventing unintentional actuation of said actuator member. The plate has at least two arms 34 extending in two substantially opposite directions and each arm 34 has a base 38 fastened to the plate and a free end 40. In an armed position the plate is plane and the arms 34 extend in a plane inclined to the plane of the plate, the arms 34 being on the same side of the plate. The free ends 40 of the arms are each disposed in a corresponding housing provided in the case.

Description

2366451 A membrane-type manual tripping device The present invention

relates to a membrane-type manual tripping device asused in safety applications, 5 for example, in particular in fire safety applications.

Providing manual tripping devices at various locations in premises, in particular in offices or places intended to receive the general public, is known in the art. When actuated, this kind of device trips an audible 10 alarm, for example, to warn of a hazard (fire etc.).

some tripping devices include a case containing a push-button. A glass window forms a front face of the case and prevents access to the pushbutton. The glass window must therefore be broken to obtain access to the push-button.

The document FR-2 495 374 cites the drawbacks of this kind of device and proposes a tripping device in which a plate is disposed over a pushbutton. The plate has, at least locally, an outwardly curved shape in the 20 armed position (before actuation) and an inwardly curved shape in the tripped position (after actuation).

The plate of this kind of device is in fact a rectangular plate having a crease in the middle. A transverse groove in line with the crease is provided on 25 the exterior face of the plate. The plate is retained in a case by its edges parallel to the groove, and therefore has two stable positions, one corresponding to the outwardly curved armed position and the other -to the inwardly depressed tripped position. The plate therefore 30 has a broken appearance, even in the armed position.

An object of the present invention is to provide a membrane-type tripping device whose membrane (plate) has, at least locally, a plane shape substantially parallel to the front face of the case in which it is mounted in its 35 armed position, and a broken appearance in its tripped positiori-. The device advantageously has no groove in the plate visible from the outside.

To this end, the present invention proposes a membrane-type manual tripping device including a case in 5 which are disposed an actuator member and a plate disposed above the actuator member that is elastically deformable between two stable positions and prevents unintentional actuation of the actuator member.

In accordance with the invention the plate has at 10 least two arms extending in two substantially opposite directions, each arm having a base fastened to the plate and a free end; in an armed position the plate is plane, the arms extend in a plane inclined to the plane of the plate, the arms are on the same side of the plate, and 15 the free ends of the arms are each disposed in a corresponding housing provided in the case.

In this way, the tripping device does not have a broken appearance for the user before it is used. Thanks to the inclined arms associated with the plate, which are 20 retained in the case at their free ends, when the plane part of the plate is deformed, the arms pass through a bracing position corresponding to a maximum force applied to the plate. Accordingly, the broken appearance is retained when the plate is in its tripped position.

25 In a preferred embodiment, corresponding from the shape point of view to the appearance of existing manual tripping devices, the plate is a rectangular plate intended to bend along its transverse median axis and the arms each extend substantially longitudinally on 30 respective opposite sides of the bend. The rectangular shape is particularly suitable here because the arms can therefore be disposed along the plate. Also, this arrangement limits the overall size of the device. In this embodiment, the base of each arm is preferably 35 beside the bend in the plate.

In- the case of a rectangular plate, to improve the distribution of forces and to improve the guidance of the plate when it moves from one position to another, the plate preferably has four arms, two on each of its 5 longitudinal sides.

To facilitate its deformation, the plate advantageously has a groove defining a bending axis, this groove being on the side that is inside the case when the plate is mounted therein, and likewise the arms.

10 To facilitate re-arming the tripping device, in other words moving the plate from its tripped position to its armed (rest) position, the device advantageously includes a re-arming lever mounted to pivot in the case.

one end of the re-arming lever is advantageously between 15 the plate and the actuator member and the other end of the re-arming lever is accessible via an opening in a front face of the case, corresponding to the face on which the plate can be seen. Providing access to the rearming lever via the front face of the case guarantees 20 easy access to the re-arming lever at all times.

The -following description, given with reference to the accompanying drawings, explains further the objects and advantages of the invention. It is clear that the description is given by way of example only and has no

25 limiting character.

Figure 1 is a perspective view of a tripping device in accordance with the invention, Figure 2 is a view corresponding to figure L of the tripping device in accordance with the invention without 30 its cover, Figure 3 is a bottom view of the cover, Figure 4 is a view in section taken along. the line IV-IV in figure 3 in the armed position, Figure 5 corresponds to figure 4 in the tripped 35 position, I Figure 6 is a view of the device from figure 1 in the armed position and in cross section taken along the line VI-VI, and Figure 7 corresponds to figure 6 in the tripped S position.

Generally speaking, a tripping device in accordance with the invention includes a case 2 having a base 4 and a cover 6.

In the embodiment shown in the drawing, the cover 6 10 is removably attached to the base 4. Attachment lugs 8 locate the cover correctly on the base and a screw 10 is provided to retain the cover 6. The base 4 and the cover 6 are substantially square.

The base 4 provides a housing for a push-button 12 15 (figures 6 and 7) associated with an electrical switch and with other components, for example electrical connecting terminals, an electrical circuit and possibly electronic components. Actuating the push-button 12 trips an audible alarm, f or example, to warn of a hazard such 20 as a fire.

The base 4 has a bottom 14 attached to side walls 16 and a cover plate 18. The latter is fixed by screws to the combination of the bottom 14 and the side walls 16, for example. Like the cover 6, the two component parts of 2S the base 4 are injection-moulded from a plastics material, for example. The push-button 12 and the various components are disposed in the base 4 and held in position therein by the cover plate 18. The latter is substantially plane and square.

30 The cover plate 18 includes a plurality of openings providing access to the push-button 12 and to the connecting terminals in particular. The push-button 12 is actuated by means of a cranked lever 20 mounted to pivot about a spindle 22 supported by two bearings. Each 3S bearing is formed at the end of a lug 23 whose end is slit longitudinally to define two elastic branches in each of which a housing is formed to receive the spindle 22. Accordingly, in a manner that is known in itself, the spindle 22 can be clipped onto the lugs 23 and pivot 5 freely in its bearings, which are defined by the housings formed in the elastic branches.

The spindle 22 is substantially in the plane of the cover plate 18. An opening is provided in the plate in line with the lever 20 and its spindle 22. The spindle 22 10 is disposed so that a free end of the lever 20 can come into contact with and actuate the push-button 12. The lever 20 is cranked so that when its first free end is in contact with the push-button 12 the branch including that free end is substantially in the plane of the cover plate 15 18 and the branch including the other free end of the lever 20 projects outwards from the base 4.

The cover 6 has a front face 24 which is surrounded by side walls 26 and in which a rectangular opening 28 is formed. The latter opening is closed by a plate 30 formed 20 by a membrane 32 and four arms 34. The plate 30 is made from a synthetic material for example, such as polypropylene. This material is able to withstand bending, which is necessary in the present application.

In its "rest" position, i.e. before actuation of 25 the tripping device in accordance with the invention, the membrane 32 is plane and rectangular. Its shape substantially corresponds to that of the rectangular opening 28, which it covers entirely. It fits inside the cover 6, i.e. between the side walls 26, and is therefore 30 on the same side thereof as the base 4 when mounted in the device. The membrane 32 has on its inside face, i.e.

on the same side as the base 4, a median transverse groove 36 dividing the membrane 32 into two equal parts and defining a bending axis.

35 The arms 34 extend longitudinally alongside the membrane- 32. Each arm 34 has a base 38 and a free part 40. The base 38 is fastened to the membrane 32, to which it is attached at one longitudinal edge, i.e. one long edge, of the membrane 32, in the vicinity of the groove 5 36. The free part of each arm 34 is always at the end opposite the groove 36. All four free parts 40 of the arms 34 are inclined to the plane of the membrane in its "rest" position and oriented towards the interior of the device.

10 The free ends of the arms 34 are substantially level with a transverse edge of the membrane. Each is housed in a housing formed in the cover 6 and enabling the arms 34 to pivot in their housing. Each housing is defined by abutments that are formed when the cover 6 is is injection moulded, for example.

The plate 30 therefore has two stable positions, shown in figures 4 and 5. In a first position (figure 4), referred to as the rest or armed position, the membrane 32 is plane and the arms 34 are inclined so that their 20 free parts 40 are farther inside the cover 6, and therefore the device, than the bases 38. The membrane 32 is then slightly stressed. In a second position (figure 5), referred to as the actuated or tripped position, the membrane 32 forms a dihedron whose ridge is inside the 25 tripping device; the free edges of the dihedron are in contact with the front face 24. The arms 34 are inclined so that their bases 38 are farther inside the cover 6, and therefore the device, than their free parts 40. The membrane 32 is therefore unstressed. The inclination of 30 the arms relative to the front face 24 is therefore reversed between the first position and the second position. The plate 30 passes through a bracing point corresponding to a maximum force applied by a user to the membrane 32 via the rectangular opening 28.

35 This is how the device works: The base 4 is f ixed to a wall or the like in premises such as an office. of course, the tripping device is electrically connected to an alarm system, for example a fire alarm. The plate 30 is in the rest position previously described. The 5 rectangular opening 28 providing access to the membrane 32 is on the front face of the device, facing a user. If the user wishes to trip the alarm, it is sufficient to press the membrane 32 in order to depress it into the interior of the case. The membrane 32 bends at the level 10 of the groove 36 and the plate 30 takes up the actuated position shown in figures 5 and 7. The membrane 32 operates on the push-button 12 via a branch of the cranked lever 20, so tripping the alarm. The lever 20 is advantageously disposed parallel to and just below the 15 ridge of the dihedron formed by the membrane 32 in its tripped position. The branch 44 of the lever acting on the push-button 12 is substantially in the plane of the cover plate 18. A projection 42 on this branch ensures that contact between the membrane 32 and the lever 20 20 occurs at the level of the projection 42, and not over the whole of the length of the corresponding branch; this achieves a cleaner contact.

As indicated above, in this tripped position the second branch 46 of the cranked lever 20 causes the cover 25 plate 18 to project towards the cover 6 and the plate 30.

To return the tripping device to its rest position, and therefore to return the membrane 32 to its plane configuration, it is suf f icient to act on the. second branch 46 of the cranked lever, which in turn acts on the 30 membrane 32. An opening 48 is provided for this purpose in the front face 24 of the cover 6, just above the second branch 46. In the embodiment shown in the drawing, the opening 48 is semicircular. This shape is to restrict access to the cranked lever 20 by necessitating the use 35 of a special tool or key. That tool, not shown, is inserted- into the case 2 via the opening 48 until it comes into contact with the second branch 46 of the cranked lever 20 and causes the latter to pivot about the spindle 22. The projection 42 on the first branch 44 of 5 the lever therefore pushes on the membrane 32, at the location of the transverse groove 36, to return it to its plane rest position. This re- arms the tripping device. The fact that the opening 48 providing access to the rearming lever is on the front face 24 of the device, 10 immediately adjacent the opening 28 corresponding to the membrane 32, guarantees easy access to the device for rearming it. Even if the case 2 is in the corner of a room or in contact with some other case, there is no problem of access for re-arming the device because, for safety 15 reasons, its front face is always readily accessible.

The scope of the present invention is not limited to the details of the embodiment considered above by way of non-limiting example, but on the contrary extends to modifications that will be evident to the skilled person 20 and are within the scope of the following claims.

For example, the shape of the membrane could be modified if a circular device were required, rather than a square or rectangular device.

It is equally possible to modify the number of arms 25 associated with the membrane. Two arms may be sufficient. It is also possible to change the orientation of the arms. They do not necessarily extend along the membrane. Without departing from the scope of the invention, the base of the arms, instead of being beside the bend in the 30 membrane, could be far away from it.

I

Claims

CLAIMS -

1. A membrane-type manual tripping device including a case in which are disposed an actuator member and a plate disposed above said actuator member, 5 elastically deformable between two stable positions and preventing unintentional actuation of said actuator member, wherein the plate has at least two arms extending in two substantially opposite directions, each arm having a base fastened to the plate and a free end, in an armed 10 position the plate is plane and the arms extend in a plane inclined to the plane of the plate, the arms being on the same side of the plate, and the free ends of the arms are each disposed in a corresponding housing provided in the case.

15

2. A tripping device according to claim 1, wherein the plate is a rectangular plate adapted to bend along its transverse median axis and the arms each extend substantially longitudinally on either side of the bend.

3. A tripping device according to claim 2, wherein 20 the base of each arm is beside the bend in the plate.

4. A tripping device according to either claim 2 or claim 3, wherein the plate has f our arms, two on each of its longitudinal sides.

5. A tripping device according to any of claims 1 25 to 4, wherein the plate has a groove defining a bending axis, said groove being on the side that is inside the case when the plate is mounted therein, likewise the arms.

6. A tripping device according to any of claims 1 30 to 5, including a re-arming lever pivotably mounted in the case.

7. A tripping device according to claim 6, wherein one end of the re-arming lever is between the plate and the actuator member.

35

8. A tripping device according to either claim 6 or claim 7, wherein one end of the re-arming lever is accessible via an opening provided in a front face of the case corresponding to the face on which the plate can be seen.

5

9. A membrane-type manual tripping device substantially as herein described with reference to the accompanying drawings.