EP3641894A1

EP3641894A1 - Thermal triggering element

Info

Publication number: EP3641894A1
Application number: EP18733561.7A
Authority: EP
Inventors: R diger KLUG; J rgen TESCHNER; Bodo M LLER
Original assignee: Job Lizenz GmbH and Co KG
Current assignee: JOB LIZENZ GmbH
Priority date: 2017-06-21
Filing date: 2018-06-19
Publication date: 2020-04-29
Also published as: DE202017103682U1; RU2733250C1; US20200129798A1; WO2018234327A1

Abstract

A thermal triggering element (1) having a vessel body (1), which has an outer wall (7) formed from a rupturing material, and having a cavity (2), which is enclosed by the outer wall (7) and which is situated in the interior of the vessel body (1) and in which a triggering liquid is enclosed, wherein the vessel body (1) is formed so as to extend along an axial direction, with a tubular central section (8) extending in the axial direction, and with two end sections (3, 4) which are situated at the respective axial ends and in which the cavity (2) is closed off in the manner of a cap, is disclosed. In order for such a thermal triggering element to be protected against damage by shocks reliably and not only during an installation process but also in a usage situation, in which said thermal triggering element is installed in a valve component or the like, it is proposed that the triggering element (1) has a permanently acting reinforcement (9) which reinforces the rupturing material with respect to shock loads acting transversely with respect to the longitudinal direction.

Description

Thermal release element

The invention relates to a thermal tripping element having the features of the preamble of claim 1.

Thermal tripping elements have long been known and used. They are used in particular and in large numbers in sprinkler and fire extinguishing systems, where they connected to a pressurized extinguishing agent (usually water) filled pipes connected outlet nozzles or sprinkler exits, holding them in their closed position, in the axial direction between an abutment and a closure element, the closure element holding in a closed position, are arranged. If the external temperature exceeds the triggering temperature to be set by appropriate and known technological measures, the bursting material of the outer wall is destroyed by the pressure rising with increasing temperature, breaks the triggering element and clears the way to open the closure element, so that the extinguishing agent exit the sprinkler nozzles or sprinkler exits and can be discharged.

In addition to an application in such sprinkler or fire extinguishing systems, applications are also known and described in which such trigger elements close pressure relief openings to release them at a triggering temperature exceeding a critical temperature, for. B. to empty compressed gas tank in case of fire in time before they can explode for example. Also Applications of such tripping elements in connection with the interruption of electrical current flow are known. Other applications are conceivable; such triggering elements can always be used when temperature-sensitive mechanical switching positions to change or electrical lines are to be interrupted.

The typical known thermal tripping elements of the type mentioned, which have been known for many years and one of which is e.g. is shown and described in DE 36 01 203 A1, are often made of glass. In this case, glass is the bursting material.

Thermal tripping elements of the type mentioned are technologically very well controlled today. One can achieve very adjustable triggering temperatures with a low tolerance threshold. The reaction times can be set very low; It can be made of very low thermal inertia thermal tripping elements of this type.

One problem with this, however, is that the thermal tripping elements, especially in a position already installed in a closure element (eg a sprinkler head or a valve closure for pressure relief openings), are sensitive to impact, in particular to impacts transversely to their longitudinal direction. Thus, it can happen that when handling such a thermal tripping element or with an assembly in which it is already integrated in a closed position (eg a sprinkler head of a sprinkler system), such a shock is inadvertently exerted on the outer wall of the thermal tripping element, that this takes damage. This can be exhausted in a cracking or even lead to a breakage of the triggering element. In both cases, however, then the function of the trigger element is no longer given, the assembly is no longer used. Experienced the outer wall of the thermal release element while only a crack or other comparable damage, this is particularly fatal, since it may go unnoticed, a later proper operation of the trigger element is not guaranteed. For example, over time could be due to such a crack Trigger liquid escape from the interior of the trigger element, so that this completely loses its function.

This danger is sometimes counteracted today by installing mounting fuses for mounting the thermal tripping elements, e.g. in the form of clipped-on protective sleeves, which then have to be removed after the handling has been completed, in order to preserve the functionality of the triggering elements. However, this approach involves the risk that a removal of these mounting fuses forgotten and so the function of the trigger element is overridden. Moreover, this measure also does not work in the case of and in the environment of in e.g. a sprinkler system already installed thermal tripping elements, as e.g. as part of maintenance work or simply as an "accident".

Here is to be remedied with the invention to the effect that the thermal tripping element against insults as described above shocks and impairments, at least less sensitive, to be made, without the need for attaching a temporary mounting fuse about it.

This object is achieved by a thermal tripping element having the features of claim 1. Advantageous developments of such a trigger element according to the invention are given in the dependent claims 2 to 9.

According to the invention, therefore, the thermal triggering element on a vessel body which comprises an outer wall formed from a bursting material. Surrounded by the outer wall is located in the interior of the vessel body, a cavity in which a triggering liquid is enclosed. This may advantageously contain a gas, in particular an air bubble. The vessel body is expanded along an axial direction and has a tubular central portion extending in the axial direction. At the respective axial ends in each case an end portion, so are a total of two end portions, located in which the cavity is closed like a cap. In that regard, the right one Inventive design of the thermal tripping element with the known from the prior art variants match.

The peculiarity of the tripping element according to the invention consists in the fact that the tripping element has a reinforcement which reinforces the bursting material against shock loads acting transversely to the longitudinal direction. This reinforcement is permanently applied to the trigger element, z.b. directly applied to the bursting material, or integrated into the bursting material and differs in this respect from a temporarily applied mounting fuse. Permanently means in the sense of this invention that the gain remains active and effective at least as long as the thermal tripping element has not yet reached its trip temperature or even triggered. Thermal tripping elements are often installed over several years, even decades, for example in sprinkler systems and remain in use there. During such a typical usage period, the gain should remain effective, at least as long as the thermal tripping element is not guided in the range of a trip temperature or even triggered.

The reinforcement provided according to the invention thus effects targeted protection of the thermal triggering element from damage or destruction by - usually inadvertent - impact action acting from outside transversely to the axial direction of the triggering element. However, the gain is chosen in such a way that it does not hinder the intended triggering operation at high temperatures in the way, and this although the gain is not just temporary, but beyond a period of assembly going out in the thermal tripping element is provided. In particular, the reinforcement provided according to the invention is designed in such a way that at the predetermined triggering temperature the pressure generated in the interior of the cavity by the heated triggering liquid reliably continues to destroy the bursting material and thus trigger the thermal triggering element. This can be achieved, for example, by generally not impeding impulse or force application in one direction out of the cavity outwardly by the reinforcement, or else in that the gain at higher temperatures, in particular in the range of the triggering temperature, overall loses its effect, or the gain that does not completely surround the thermal tripping element.

One way of forming a reinforcement according to the invention is by containing auxetic material, this material being oriented in such a way that it exerts a reinforcing effect on external force acting transversely to the axial direction. An auxetic material is characterized by a behavior that is abnormal in comparison to conventional materials, in that this - usually only in certain preferred directions - does not become thinner in the material layer during stretching of the material, but instead forms a thicker material layer there. Corresponding materials are already known, they exist at the macroscopic level, but are already described in the molecular field, in particular in the form of so-called prismanes. Auxetic materials are described by various suppliers and offered on the market. An alternative or additional way of obtaining the reinforcement is to form it using one or more dilatant fluid (s) or a material made therefrom, for example a foam. Dilatant liquids are liquids that change their flexibility and deformability under the influence of force. In particular, such liquids may become solid and rigid with sudden forces and have energy absorbing qualities. The functional principle is based on atomic bonds in the molecular structure, which form under pressure and after completion of the

Release force again. Using such liquids, for example, foams or comparable materials can be produced which, if the liquids themselves can not already be used as reinforcement, can be used to form the reinforcement according to the invention.

Another possibility for realizing the reinforcement according to the invention is that it comprises a material which is fixed in a temperature range below an intended triggering temperature of the triggering element is stiff, so is able to absorb shocks and thus protect the trigger element, however, at the release temperature is yielding. Such materials may be, for example, plastics with a correspondingly low softening or melting point, which form a solid protective layer or reinforcement at a typical ambient temperature, in particular room temperature, but which soften at higher temperatures and are so soft and flexible at the release temperature at the latest they no longer stand in the way of a bursting of the bursting material from which the triggering element is formed.

For an embodiment of the reinforcement, provision may in particular be made for it to have an impregnated or coated textile structure produced with one or more of the materials described above. A textile structure may be a thread, which may be e.g. is wrapped around the trigger member or a portion thereof to form the reinforcement. Also, a textile sleeve, which is placed over the trigger element or overstretched, can be used.

The reinforcement provided according to the invention may in particular be a coating applied to the outer wall or a sleeve placed on the outside of the outer wall or a protective curtain arranged on the outer side of the outer wall. Alternatively, the reinforcement can of course also be integrated in the bursting material, however, the application of a coating or the laying on of a collar or protective curtain according to the current state is much easier to implement and correspondingly less expensive to implement. Corresponding coatings can be applied, for example by way of a dip bath, to otherwise finished thermal release elements. Also, spraying with a coating material or foaming a coating material is possible. In principle, all conceivable coating mechanisms can be selected here. Optionally, an adhesive layer may be applied prior to applying the actual coating. The reinforcement may, but need not, be applied over the entire surface of the thermal tripping element. It can just as well be provided only in sections, preferably in those sections which are particularly at risk for impacts transverse to the axial direction. In that regard, it is preferable that the reinforcement is provided along substantially the entire middle portion.

In order to ensure, when using the thermal tripping element according to the invention in a sprinkler head, that when triggering the thermal tripping element and activating the sprinkler, the material of the reinforcement does not, e.g. can hang on a distributor or spray plate of the sprinkler and the distribution of the escaping extinguishing water obstructed or impaired, it can be provided that the reinforcement consists of a water-soluble material or contains a water-soluble carrier material. Advantageously, the water-dissolving properties are then determined so that the material does not weaken or dissolve due to slight moistening, e.g. can be obtained by condensation or the like. This ensures that the protective effect of the reinforcement is maintained, that the material only dissolves when it comes into contact with the considerable amounts of water that occur when the sprinkler is triggered.

Preferably, glass will be provided as the bursting material. However, it is also possible to use another material which has corresponding bursting properties.

Further advantages and features of the invention will become apparent from the following description of embodiments with reference to the accompanying figures. Showing:

Fig. 1 is a schematic representation of a thermal tripping element according to the invention in a longitudinal section;

Fig. 2 a Fig. 1 comparable cross-sectional representation of a thermal

Trigger element with an alternative reinforcement; Fig. 3 a Fig. 1 comparable representation of a thermal tripping element with a further alternative reinforcement, wherein the tripping element is not shown here cut;

Fig. 4 a Fig. 3 comparable illustrations of a thermal tripping element with a further alternative reinforcement; and

Fig. 5 a Fig. 3 comparable illustrations of a thermal tripping element with a further alternative reinforcement;

In the figures, purely schematic representations are shown which serve to explain the invention, and by no means are true to scale or detail.

In the figures, in each case a thermal tripping element is shown, which here is a so-called glass keg, as it is known in principle from the prior art. Thus, the glass keg shown here essentially corresponds in its design to the shape and design described in DE 36 01 203.

A vessel body 1 of the glass cask completely encloses a cavity 2 with an outer wall 7, and is divided into a middle portion 8 which is tubular and elongated in an axial direction, and two end portions 3 formed at the respective axial ends of the middle portion 8, 4, in which the cavity 2 is closed like a cap. In the exemplary embodiment shown, the end sections 3, 4 are shown as having material thickenings (an enlargement of the diameter relative to the middle section 8). These thickenings are not required. The end sections 3, 4 can just as well be formed with a diameter which is unchanged relative to the middle section 8, that is to say without the thickenings shown here.

Within the cavity 2, not shown here, a triggering liquid is arranged and is also a gas bubble. The outer wall 7 of the vessel body 1 is made of a bursting material, here in particular glass. The glass keg with its vessel body in this embodiment has a total length of about 1 2 to 50 mm. The glass keg is in its use as a trigger element with the opposite end portions 3 and 4 on bearing elements 5 and 6, is clamped between them. These bearing elements 5, 6 are not part of the thermal tripping element, but parts of an assembly in which the trigger element is used, for example a sprinkler head or a pressure relief valve of a gas container. In particular, one of the bearing elements 5, 6, for example, the bearing element 5 may be a valve plate of a sprinkler, the other position element, for example, the bearing element 6, an opposite bearing bracket, as it is often encountered in sprinkler systems. Equally, however, the glass keg can also be integrated as a thermal triggering element in an emergency discharge valve of a gas container or in similar devices. Those skilled in the art are familiar with such components, so that their specific shape and function need not be discussed further here.

If an elevated temperature prevails in the vicinity of the outer wall 7, which causes the triggering liquid in the interior of the cavity 2 to generate a sufficiently high pressure to burst the outer wall 7 consisting of the bursting material, the vessel body 1 of the glass cask breaks in a known manner. So then the broken glass keg, e.g. a distance between the bearing elements 5, 6, between which it is arranged, free. In the case of a sprinkler system, the closure element of the sprinkler nozzle can then escape the pending pressure of the sprinkler liquid and the nozzle opens. In the case of a pressure relief valve for e.g. a pressurized gas container, opens this valve, gas can flow out of the container controlled.

The essential feature of the invention is now a reinforcement 9 of the vessel body 1. This is permanently formed in a manner as described above. The reinforcement 9 is realized in different embodiments in the embodiments shown. So it is in the example of FIG. 1 realized in the form of a coating on the outer wall 7 in the middle section 8. This may for example consist of an auxetic polymer. The coating can be applied by dipping, brushing, printing or by spraying. FIG. 2 shows an example in which the reinforcement 9 is formed by a protective material contained in a textile carrier structure. For example, the textile support structure may be impregnated, impregnated or coated with an auxetic material or a dilatant fluid. This textile carrier structure, for example a textile fabric, can be applied to the glass keg 1 in the manner of a coating, if necessary with prior application of a primer to which the carrier structure then adheres and is thus fixed to the glass keg 1. The textile support structure treated in the above-described manner can be prepared in such a way that a shock protection acting in three dimensions results (for example, by auxetic material arranged in such a way that it is effective in three dimensions).

Fig. 3 shows an embodiment in which the reinforcement 9 has the shape of a sleeve, here one of diagonal crosswise extending material webs. These material webs may in turn be made of an auxetic material, a material formed with a dilatant fluid (eg a foam formed therefrom) or a hard and rigid in a range far below the firing temperature of the glass vial 1, soft and tearable or dissolvable at the firing temperature be formed (eg evaporating) material. Basically, here also a simple foam or a foamed polymer can be used, which already intercepts shocks due to its buffering properties, which can occur transversely to the longitudinal direction of the glass bottle 1.

4 shows a realization of the reinforcement in which a material coated or impregnated with an auxetic material or impregnated with a dilatate liquid or obtained from a dilatant liquid or from a hard material in a range well below the triggering temperature of the glass bottle 1 rigid, at the release temperature soft and tearable or dissolving material formed thread is wound around at least a portion of the glass cask to form the reinforcement. Fig. 5 shows a realization of the reinforcement in which a protective curtain of, for example, textile threads coated or impregnated with an auxetic material or impregnated with a dilate liquid or formed from a material obtained from a dilatant fluid is formed. The threads extend in a longitudinal direction of the glass bottle and are connected at opposite longitudinal ends, each with a circumferential retaining ring. The retaining rings are fixed to the thickened end portions 3 and 4 on the glass kegs 1, for example glued. In the middle section 8, the threads hanging loose like a curtain, but are so streamlined that they run at a distance from the outer wall 7 in the central portion 8 and can not be pressed against the outer wall 7 there. Instead of individual thread elements, the protective curtain can also be formed continuously and sleeve-like, for example from a fabric having the properties described above by the measures described. This solution has the advantage that the protective curtain does not adhere to the central portion 7 in a triggering case of the glass bottle 1, that is, when the glass bottle 1 bursts due to the reaching of the triggering temperature, and thereby does not change the triggering properties of the glass bottle 1.

However, the reinforcement can also, not shown here, just as well be integrated into the bursting wall forming the outer wall.

The reinforcement 9 is always designed in all cases and in other embodiments not shown here, so that it results in a solidification of the vessel body 1 against shocks and comparable mechanical effects, this in a direction transverse to its axial extent (in the figures transverse to the vertical) experiences. A triggering of the thermal tripping element (the glass vial) at the release temperature is not hindered by this. Rather, the triggering or reaction behavior of the glass bottle is still good, in particular continue short tripping or reaction times at the predetermined release temperatures guaranteed. In particular, the reinforcement does not hinder the heat transport in the direction of the cavity and the triggering liquid arranged therein, at most impairs it in such a small way that the tripping characteristic of the thermal tripping element is not changed.

This protection according to the invention against impacts and comparable external mechanical effects is realized in that the reinforcement contains an auxetic material and / or one or more dilatant liquid (s) (or a material produced therefrom, eg a foam) and / or comprises a material, which is solid and stiff in a temperature range below an intended trip temperature of the trigger element that is compliant at the trip temperature.

When an auxetic material is used, it is aligned in the reinforcement in such a way as to exert a reinforcing effect on external force directed transversely to the axial direction.

This embodiment of the invention provides the advantage that a thermal release element thus formed not only during handling during assembly, but also later in use against accidental damage by external mechanical influence, in particular shocks, is secured, but at the same time still reliable and with the required fast response time to the set trip temperature triggers.

LIST OF REFERENCE NUMBERS

1 vessel body

2 cavity

3 end section

4 end section

5 bearing element

6 bearing element

7 outer wall

8 middle section

9 reinforcement

Claims

claims

1 . Thermal triggering element (1) having a vessel body (1) comprising an outer wall (7) formed from a bursting material and a cavity (2) enclosed by the outer wall (7) and located inside the vessel body (1), in which a triggering liquid is enclosed wherein the vessel body (1) is formed to be expanded along an axial direction with a tubular central portion (8) extended in the axial direction and two end portions (3, 4) located at the respective axial ends, in which the cavity (2) cap-like manner, characterized in that the triggering element (1) has a the bursting material against acting transversely to the longitudinal direction shock loads reinforcing, permanently acting reinforcement (9).

2. Thermal tripping element (1) according to claim 1, characterized in that the reinforcement (9) contains an auxetic material, wherein the auxetic material is aligned in such a way that it is directed at transversely to the axial direction directed external force on the outer wall ( 7) shows a reinforcing effect.

A thermal tripping element (1) according to any one of the preceding claims, characterized in that the reinforcement (9) comprises one or more dilatant liquid (s) or a material made therefrom, e.g. a foam.

4. Thermal tripping element (1) according to any one of the preceding claims, characterized in that the reinforcement (9) comprises a material which is solid and stiff in a temperature range below an intended release temperature of the triggering element, which is yielding at the triggering temperature.

5. Thermal tripping element (1) according to any one of the preceding claims, characterized in that the reinforcement (9) is one with an auxetic material, one or more dilatant liquid (s) or a a material produced from one or more dilatant fluid (s) and / or a material that is solid and stiff in a temperature range below a designated release temperature of the trigger element that is compliant at the deployment temperature, having impregnated or coated textile structure.

6. Thermal tripping element (1) according to any one of the preceding claims, characterized in that the reinforcement (9) on the outside of the outer wall (7) applied coating or on the outside of the outer wall (7) laid cuff or on the outside the outer wall (7) arranged protective curtain comprises.

7. Thermal tripping element (1) according to any one of the preceding claims, characterized in that the reinforcement (9) along substantially the entire central portion (8) is provided.

8. Thermal tripping element (1) according to one of the preceding claims, characterized in that the reinforcement (9) consists of a water-soluble material or contains a water-soluble carrier material.

9. Thermal tripping element (1) according to one of the preceding claims, characterized by glass as bursting material.