THERMAL TRIGGERING ELEMENT

Abstract

A thermal triggering element having a vessel body with an outer wall formed from a rupturing material, and having a cavity enclosed by the outer wall and situated in the interior of the vessel body, and in which a triggering liquid is enclosed. The vessel body is formed so as to extend along an axial direction, with a tubular central section extending in the axial direction, and with two end sections located at the respective axial ends and in which the cavity is closed off in the manner of a cap. In order for the thermal triggering element to be protected against damage by shocks, the triggering element has a permanently acting reinforcement which reinforces the rupturing material with respect to shock loads acting transversely with respect to the longitudinal direction.

Claims

1. A thermal triggering element comprising: a vessel body having an outer wall formed from a rupturing material; a cavity enclosed by the outer wall and which is situated in an interior of the vessel body; a triggering liquid enclosed in the cavity; wherein the vessel body is formed so as to extend along an axial direction, with a tubular central section of the vessel body extending in the axial direction, and with two end sections which are situated at respective axial ends of the tubular central section; and in which the cavity is closed off in the manner of a cap; wherein the triggering element has a permanently acting reinforcement which reinforces the rupturing material with respect to shock loads acting transversely with respect to the axial direction.

2. The thermal triggering element according to claim 1, wherein the reinforcement contains auxetic material, wherein the auxetic material is oriented in a manner such that it exhibits a reinforcing effect on the outer wall upon an external application of force directed transversely with respect to the axial direction.

3. The thermal triggering element according to claim 1, wherein the reinforcement has one or more dilatant liquids or a material produced therefrom.

4. The thermal triggering element according to claim 1, wherein the reinforcement has a material which is solid and stiff in a temperature range below an intended triggering temperature of the triggering element, and wherein the material is flexible at the triggering temperature.

5. The thermal triggering element according to claim 1, wherein the reinforcement has a textile structure which is produced, impregnated, or coated with an auxetic material, one or more dilatant liquids, or a material produced from one or more dilatant liquids, and/or from a material which is solid and stiff in a temperature range below an intended triggering temperature of the triggering element and which is flexible at the triggering temperature.

6. The thermal triggering element according to claim 1, wherein the reinforcement comprises a coating applied to an outer side of the outer wall, or a collar placed on the outer side of the outer wall, or a protective curtain arranged on the outer side of the outer wall.

7. The thermal triggering element according to claim 1, wherein the reinforcement is provided essentially along the entire tubular central section.

8. The thermal triggering element according to claim 1, wherein the reinforcement is a water-soluble material or a water-soluble carrier material.

9. The thermal triggering element claim 1, wherein the rupturing material is glass.

10. The thermal triggering element according to claim 3, wherein the one or more dilatant liquids or the material produced therefrom is a foam.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0020] Further advantages and features of the inventions result from the following description of exemplary embodiments by means of the enclosed figures. The following is shown:

[0021] FIG. 1 a schematic representation of a thermal triggering element according to the invention in a longitudinal section;

[0022] FIG. 2 a cross-sectional representation, comparable to FIG. 1, of a thermal triggering element with an alternative reinforcement;

[0023] FIG. 3 a representation, comparable to FIG. 1, of a thermal triggering element with a further alternative reinforcement, wherein the triggering element in this case is not sectionally shown;

[0024] FIG. 4 a representation, comparable to FIG. 3, of a thermal triggering element with a further alternative reinforcement; and

[0025] FIG. 5 a representation, comparable to FIG. 3, of a thermal triggering element with a further alternative reinforcement.

DETAILED DESCRIPTION

[0026] The figures show purely schematic representations, which are intended to explain the invention, and are in no way true to scale or accurate in detail.

[0027] The figures each show a thermal triggering element, which is a glass vessel here, as is basically known from the prior art. Thus, the glass vessel shown here corresponds in design substantially with the form and characteristics described in DE 36 01 203.

[0028] A vessel body 1 of the glass vessel completely encloses a cavity 2 with an outer wall 7 and is divided into a central section 8, which is tubular and extends longitudinally in an axial direction, as well as two end sections 3, 4, which are formed at the respective axial ends of the central section 8, within said end sections the cavity 2 is closed off in the manner of a cap. In the exemplary embodiment shown, the end sections 3, 4 as such are shown with material thicknesses (of a diameter expansion as compared to the central section 8). However, these thickenings are not necessary. The end sections 3, 4 may just as well be formed with a diameter that is unchanged as compared to the central section 8 that is formed without the thickenings shown here.

[0029] A triggering liquid is arranged within the cavity 2, not shown here, as well as a gas bubble. The outer wall 7 of the vessel body 1 is produced from a rupturing material, particularly glass in this case. The glass vessel with its vessel body has a total length of about 12 to 50 mm in this exemplary embodiment.

[0030] In its use as a triggering element, with the end sections 3 and 4 opposite one another at bearing elements 5 and 6, the glass vessel is clamped between them. These bearing elements 5, 6 are not a component of the thermal triggering element but are parts of an assembly, in which the triggering element is used, e.g. of a sprinkler head or of a pressure-relief valve of a gas container. In particular, one of the bearing elements 5, 6, e.g. bearing element 5, may be a valve disk of a sprinkler, while the other bearing element, e.g. bearing element 6, may be a bearing bracket opposite said bearing element, as is to be encountered frequently in sprinkler systems. In a similar manner, the glass vessel, however, may also be integrated, as a thermal triggering element, into an emergency release valve of a gas container or in similar devices. Such components are known to one skilled in the art such that the specific design and function thereof does not have to be further discussed at this juncture.

[0031] If there is an increased temperature in the environment of the outer wall 7, with the temperature enabling the triggering fluid to generate sufficient high-pressure in the interior of the cavity 2 to rupture the existing outer wall 7 from the rupturing material, the vessel body 1 of the glass vessel ruptures in a known manner. Thus, the destructed glass vessel exposes, for example, a distance between the bearing elements 5, 6 between which it is arranged. In the case of a sprinkler system, the closing element of the sprinkler nozzle may deflect the applied pressure of the sprinkler liquid, which opens the nozzle. In the case of an emergency release valve for a gas container, for example, under pressure, this valve opens and gas can flow out of the container in a controlled manner.

[0032] A reinforcement 9 of the vessel body 1 is then essential to the invention. This reinforcement is permanently formed in the manner previously described. The reinforcement 9 in the exemplary embodiments shown is implemented in different forms. Thus, the reinforcement is implemented in the form of a coating on the outer wall 7 in the central section 8 in the example according to FIG. 1. This may be from, for example, an auxetic polymer. The coating can be applied through immersion, brushing, printing, or even through spraying.

[0033] FIG. 2 shows an example in which the reinforcement 9 is formed from a protective material containing a textile carrier structure. For example, the textile carrier structure may be soaked, impregnated, or coated with an auxetic material or a dilatant liquid. This textile carrier structure, e.g. a textile fabric, may be applied to the glass vessel 1 as a type of coating, optionally with prior application of an adhesive primer, to which the carrier structure then adheres and thus is secured on the glass vessel 1. The textile carrier structure treated in the previous manner may be prepared such that a shock protection results, which is effective in three dimensions (e.g. by means of an auxetic material arranged such that it is effective in three dimensions).

[0034] FIG. 3 shows a design in which the reinforcement 9 has the form of a collar of material webs extending diagonally crosswise in this case. This material webs may then, in turn, be formed from an auxetic-acting material, a material formed with a dilatant liquid (e.g. a foam formed therefrom), or from a material which hardens and becomes rigid and is arranged well below the triggering temperature of the glass vessel 1, and which softens and becomes tearable or dissolves (e.g. evaporates) at the triggering temperature. Basically, a simple foam and/or a foamed polymer may be used in this case, which absorbs shocks, which may occur transversely with respect to the longitudinal direction of the glass vessel 1, due to its buffer properties.

[0035] FIG. 4 shows an implementation of the reinforcement in which a material coated or impregnated with an auxetic material, or a material impregnated with a dilatant liquid, or a material obtained from a dilatant liquid, or a material which is hard and rigid and arranged far below the triggering temperature of the glass vessel 1, or thread which softens and tears at the triggering temperature or is formed from self-dissolving material, said thread being wound around at least one section of the glass vessel, in order to form the reinforcement.

[0036] FIG. 5 shows an implementation of the reinforcement in which a protective curtain is formed, said curtain being made of, for example, textile threads, which are coated or impregnated with an auxetic material or impregnated with a dilatant liquid or which are formed from a material obtained from a dilatant liquid. The threads extend in a longitudinal direction of the glass vessel and are each connected to a circumferential retaining ring at longitudinal ends opposite one another. The retaining rings are established, e.g. bonded, on the thickened end sections 3 and 4 on the glass vessel 1 In the central section 8, the threads hang loose in the manner of a curtain but are tightened such that they extend at a distance from the outer wall 7 in the central section 8 and cannot be pressed against the outer wall 7 there. Instead of individual thread elements, the protective curtain may also be formed contiguously and in the manner of a sleeve, e.g. from a fabric having the previously described properties due to the described measures. This solution has the advantage that the protective curtain does not adhere to the central section 7 if the glass vessel 1 is triggered, that is when the glass vessel 1 ruptures due to achievement of the triggering temperature, and thereby does not change the triggering properties of the glass vessel 1.

[0037] However, the reinforcement (not shown here) may just as well be integrated into the rupturing material forming the outer wall.

[0038] In all the cases shown and also in other exemplary embodiments not shown here, the reinforcement 9 is always designed such that it results in a reinforcement of the vessel body 1 against shocks and comparable mechanical effects, which it may experience in a direction transverse with respect to its axial extension (that is transverse to the vertical in the figures). A triggering of the thermal triggering element (of the glass vessel) at the triggering temperature is thereby not impeded. Instead, if the triggering and/or response behavior of the glass vessel is approximately unchanged, particularly continued brief triggering and/or response times are ensured with the defined triggering temperatures. In particular, the reinforcement does not impede the transport of heat in the direction of the cavity and the triggering fluid arranged therein; it influences them at most in such a minimal manner that the triggering characteristics of the thermal triggering element are not changed.

[0039] This protection against shocks and comparable mechanical effects according to the invention is implemented externally in that the reinforcement contains an auxetic material and/or one or more dilatant liquids (or a material produced therefrom, e.g. a foam) and/or has a material, which is solid and rigid in a temperature range below a specified triggering temperature of the triggering element, said material being flexible at the triggering temperature.

[0040] If an auxetic material is used, it is oriented in the reinforcement in such a manner that it exhibits a reinforcing effect on the outer wall upon the application of external force directed transversely to the axial direction.

[0041] This design according to the invention obtains the advantage that a thermal triggering element thus formed is protected against undesired damage due to external mechanical influence, particularly shocks, not only during handling during assembly but also later in use; however, said triggering element simultaneously furthermore reliably triggers and does so with the necessary quick response time regarding the set triggering temperature.

LIST OF REFERENCE NUMERALS

[0042] 1 Vessel body [0043] 2 Cavity [0044] 3 End section [0045] 4 End section [0046] 5 Bearing element [0047] 6 Bearing element [0048] 7 Outer wall [0049] 8 Central section [0050] 9 Reinforcement