EP3125954A2

EP3125954A2 - Indicator body for objects made of wood, in particular a transport pallet

Info

Publication number: EP3125954A2
Application number: EP15722433.8A
Authority: EP
Inventors: Matthias Lins
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-03-31
Filing date: 2015-03-19
Publication date: 2017-02-08
Also published as: DE112015001550A5; WO2015149751A2; DE102014104528A1; WO2015149751A3

Abstract

The invention relates to an indicator body (1, 21) for a transport pallet, for at least partially arranging in a cavity (51, 52) of a structural element (50) of the transport pallet. According to the invention, in order to enable better monitoring of the thermal sterilization of a transport pallet, the indicator body (1, 21) comprises a triggering segment (2, 22) for arranging in the interior of the structural element (50) and an indicating segment (3, 23) for arranging on an outer face of the structural element (50), wherein an indicating process having a visible change in the region of the indicating segment (3, 23) can be triggered by the exceedance of a specified sterilization temperature in the region of the triggering segment (2, 22), which change is irreversible with respect to a subsequent fall below the sterilization temperature.

Description

Indicator body for articles of wood, in particular a

pallet

The invention relates to an indicator body for articles made of wood, in particular a transport pallet. The invention relates to

Further, a transport pallet and a manufacturing method for this.

The object of the present invention is to provide an indicator body capable of displaying, for all wood materials, whether the wood has been subjected to a suitable heat treatment which has killed the pests present in the wood. Thus, the indicator body is unrestricted for all articles Wood can be used and used. Without expressly limiting the general public, in the present application and the use for transport pallets as one of the most essential applications of the inventive concept is described in detail.

Transport pallets are used for loading and transporting various goods. This can be within a warehouse, but also for road and rail transportation within a country or even in global trade. The goods to be transported are stacked on the pallet and optionally additionally secured by wrapping or shrink-wrapping in foil. The pallet has lateral recesses into which the lifting devices of forklifts or the like can be inserted. can intervene. For the construction of transport pallets, wood and wood-based materials have proven to be useful, as they are inexpensive and have the required stability. One example of this is the Europool range, in which a wooden lath support rests on a series of blocks that are joined together again by boards. A problem with international and, in particular, global trade, is that the wood-made elements of a pallet can trap wood pests and other organisms that, if necessary, can be introduced to other countries and even continents with the pallet. For wood-based materials, this problem usually does not exist as the manufacturing process kills any pests. Even wood which has been subjected to drying at a sufficiently high temperature for long enough no longer contains harmful organisms. For this reason, for example, the "International Standards for Phytosanitary Measures" (ISPM 15) require additional heat treatment for wood packaging material such as transport pallets. In this case, the material must be heated continuously, ie also in the core, for at least 30 minutes to above 56 ° C. A corresponding sterilization is indicated by an identification of the pallet (inscription or imprint). However, this system is easily circumvented by affixing the label without first performing the time and energy consuming sterilization. This can not be reconstructed without detailed examination of the pallets later.

Against this background, it is the object of the present invention to propose measures that allow better control of the thermal sterilization of a transport pallet.

The object is achieved by an indicator body with the features of claim 1, a transport pallet with the features of claim 18 and by a method having the features of claim 19. It should be expressly clarified that the indicator body according to the invention can be used for all wood products which have to meet the requirements outlined in the task. In addition to the transport pallets serving as explanatory examples below, these also include crates, crates, which are used to designate containers made of saver formwork, but also container lumber for transport purposes and packaging.

According to the invention, an indicator body is provided for a transport pallet. The indicator body is provided for at least partial disposition in a recess of a structural element of the transport pallet. The corresponding construction element may in this case be, in particular, a block of wood or wood-based material. The indicator body includes a trigger section for placement within the structural member and a display section for placement on an exterior of the structural member. "On an outside" means here that the display section is located in the area of the outside and is readily visible from the outside. The display portion may protrude at least partially outwardly, but it may also terminate immediately with the side surface of the structural element or even (slightly) offset from this inwardly. Preferably, the trigger section can be arranged in the center of the structural element to be exposed to the core temperature. If the construction element for which the indicator body is provided, for example, a block of a Europoolpalette with a length and width of 145 mm, the dimension of the display section should correspond to the release section in about half, so about 72 mm. The indicator body may have a collar or the like. that prevents the display section from being inserted too far into the recess. According to the invention, by exceeding a predetermined sterilization temperature in the region of the triggering section, a display process with a visible change in the region of the display section can be triggered, which change is irreversible in relation to a subsequent undershooting of the sterilization temperature. The sterilization temperature here is a temperature that is considered safe to kill harmful organisms. This can be z. B. 56 ° C, but it can also be selected for safety an overlying temperature. Thus, according to the "Plant Protection Convention" (IPPC), a short-term warming to 80 ° C is considered sufficient, as it is assumed that a total of a sufficiently long heat treatment was done with lethal temperatures for harmful organisms. As a rule, the sterilization temperature will be between 55 ° C and 90 ° C. Higher temperatures can adversely affect the wood of the pallet and are usually unnecessary for killing harmful organisms.

The decisive factor here is that in the trigger section, which is located inside the structural element, the corresponding temperature is reached. However, since the trigger section is normally not visible from the outside, a display operation is provided in the external display section. This display process, which can also be called an "indicator reaction", is triggered by the triggering section. There are various possibilities for this, as will be explained below. In any case, a change is visible in the display section, which thus indicates the exceeding of the sterilization temperature in the triggering section. The display process may be delayed compared to the triggering exceeding the sterilization temperature, which possibly also desired to demonstrate a sufficiently long thermal treatment.

The indicator body according to the invention allows a reliable control whether the corresponding construction element (and thus the entire transport pallet) has been subjected to thermal sterilization. The indicator body is pre-determined e.g. introduced into the recess as part of the manufacturing process of the pallet. This can be done by insertion or light impact, but it is also a screwing the indicator body conceivable or if the construction element is made of wood material, this could even be "urgeformt" around the indicator body around. In addition, it is also conceivable that the recess is at least partially made by the indicator body itself, for example by hammering the same in the manner of a nail or by screwing, wherein the indicator body cuts into the recess. In each of the two cases, however, a recess will normally already be predetermined, which may possibly only be enlarged by the introduction of the indicator body. The pallet is subjected to the heat treatment together with the indicator body, whereby the display operation is triggered in the display section. After completion of the heat treatment, the temperature in the trigger section drops below the sterilization temperature. However, the change in the display section underlying the display process is irreversible to this temperature change, i. the change is retained. Thus, the thermal treatment can sustainably be understood by an optical observation of the display section of the indicator body.

The indicator body usually comprises a housing that encloses the internal, functional components. The housing may be formed of metal, although other materials, such as, for example, ceramics, plastics or even wood or wood-based materials come into question. It should be noted that the indicator body is at least partially received protected within the construction element and thus is not exposed to major mechanical stress. In addition, the temperatures used for thermal sterilization are typically well below the melting points of common plastics. When metal housings are used, the cross section thereof should be minimized to minimize heat conduction between the outer display portion and the inner trigger portion. Of course, a single section of the housing could be made of a poor thermal conductivity material, which thus represents a kind of thermal barrier.

One of the solutions which are particularly interesting according to the invention consists in introducing into the triggering section and possibly also into the display section a protein which has the property of denaturing upon reaching the sterilization temperature. This is also visually recognizable. As a special case from the large area of proteins, we name the protein as an example. In principle, the temperature at which the proteins denature can vary depending on the structure and chemical structure of the protein.

By appropriate adjustment of the chemical and structural structure of the protein, a turnover of the protein at the sterilization temperature can be achieved. From a chemical point of view, denaturation does not disrupt the covalent bonds, thus preserving the chain structure and sequence of the building blocks, and thus the primary structure. On the other hand, there is a fundamental change in the secondary and tertiary structure of the protein and thus possibly also the quaternary structure. The process of denaturation is irreversible in almost all proteins, especially proteins. Thus, the protein used has exactly the required properties, namely that it undergoes an irreversible change when the sterilization temperature is reached, which is generally well detectable via the display section. From the protein, as a special protein, these properties are well known and in particular can also be recognized optically by the entering at the sterilization temperature denaturation. Thus, the protein, which is at least partially proteinaceous, since it is still liquid in the raw state, is often referred to as egg white, which separates the spatial structure between the proteins in order to subsequently network and knot together in novel ways. The protein then becomes opaque and increasingly becomes a solid mass. The egg white is known to denature at 60 ° C, whereas the egg yolk at a higher temperature of 68 ° C.

According to a preferred embodiment, the triggering section contains a solid triggering substance, wherein melting of the triggering material and at least partial outflow into the display section can be achieved by exceeding the sterilization temperature. Here as well as below, "exceeding" means that the temperature reaches a value above the sterilization temperature. This may possibly also be the case somewhat above the intended sterilization temperature. However, it is disadvantageous if, for example, in the above case, the triggering material only melts significantly above the sterilization temperature (eg 20 ° C. above), since this makes the detection of sterilization according to the invention more difficult. This means that said solid has a melting temperature in the range or possibly slightly above the sterilization temperature. Is the temperature below it, the triggering substance, which may be in the form of a block, granules, powder or otherwise, is held in the triggering section due to its solid structure. If the triggering material melts, its mobility increases and it can flow, for example through a predetermined channel, at least partially into the display section. The display section can here, as in the embodiments described below, have a reservoir with a viewing window, through which the triggering material is visible. The visibility of the initially liquid triggering material in the region of the display section is particularly pronounced and is therefore recommended if the triggering substance is a dye or a mixture of which at least one component represents a dye. The use of a distinctive color makes the reliable reading of the display section much easier.

Said embodiment can be improved in that the indicator body comprises a spring-loaded piston, which is blocked by the solid release material and is adapted to press this after melting of the triggering material in the display section. In this case, the triggering substance in a solid state effectively forms a plug within a cylinder or the like, in which the piston is arranged. As a result of the melting of the triggering material, the plug loses its consistency, and the piston can move, pushing the at least partially liquefied triggering material in the direction of the display section.

A further preferred embodiment of an indicator body with a spring-loaded piston is that the spring is blocked in the compressed state by the solid triggering substance. Upon reaching the melting point of the triggering material, the spring is released and is thus capable of the piston under the action of Press spring force into the display section. The difference from the above-described embodiment is that the triggering material does not now block the movement of the piston, but fixes the spring in the compressed state, and that until the melting point is reached.

While in principle by the use of the indicator body according to the invention, the manipulation possibilities are reduced insofar as at least one corresponding indicator body procured and heated to the sterilization temperature, additional precautions can be taken to ensure that the indicator body has actually been in the recess during the heating and was not subsequently used there. This can be achieved, for example, by the triggering section containing a solid bonding substance, wherein melting of the bonding substance and at least partial outflow into the recess can be achieved by exceeding the sterilization temperature. The compound may in this case possibly be made of the same material as the above triggering material. It is conceivable in particular that the two substances are stored in separate chambers. While the release material requires a kind of connection channel to the display section, an outwardly leading opening or channel is provided for the connection material, which allows the liquefied compound to flow out into the recess. Alternatively, however, it is also conceivable for one and the same substance to serve as a triggering substance and as a connecting substance, wherein the indicator section may, for example, comprise a reservoir, which is connected to the outside of the indicator body via at least one connecting channel. In this case, the triggering material can first get into the reservoir, where he z. B. is observable via a viewing window, and then via the connecting channel into the recess. The bonding substance may have binder-like properties, so that after the outflow and re-solidification in the recess, a connection between the construction element and the indicator body is reinforced. In any case, however, it will be demonstrated by the presence of compound in the recess that the indicator body has been within the structural element during the heating.

According to a further embodiment of the invention, the triggering section contains a fluid triggering substance, through the expansion of which the display process can be triggered when the sterilization temperature is exceeded. "Fluid" may mean liquid or gaseous. In particular, gases are known to increase in temperature, a strong increase in volume or pressure. It is also conceivable here that a liquid triggering material at least partially evaporates by exceeding the sterilization temperature. The said expansion can be done freely, so without obstacles, the triggering material, for example, simply flows into the display section. Through the profile of a channel or through a valve assembly, backflow can be prevented. However, the expansion work of the triggering material can also be used to influence another element. For example, the indicator body can have a blocking element which limits the expansion of the fluid release substance and which can be destroyed by an increase in pressure of the fluid release substance when the sterilization temperature is exceeded. Destruction here includes any deformation that cancels the blocking function. A typical example of such a blocking element is a membrane which bursts under the pressure of the triggering material. The blocking element can eg in Display section be visible. However, it can also lie further inwards, wherein the triggering material which has passed through the blocking element is possibly visible in the display section. The variant of the invention described here can also be used in conjunction with a start-up solid triggering material, which is first liquefied by increasing the temperature.

The blocking element can also be used to separate the components during reaction mixtures of two (or more) components until, when the sterilization temperature has been reached, the blocking element z. B. is removed by melting and thus the two (or more) components can react. Similar to the polyurethane foam known in the construction industry, foaming and expansion and consequently inflow into the display section are obtained. These processes are usually irreversible. In view of the fact that during production, the two components and the blocking element located therebetween are to be introduced into the triggering section of the indicator body, correspondingly careful work in the production is required and the production costs are classified as not insignificant.

Preferably, the display process can be triggered by flowing the fluid release substance into the display section. In this embodiment, the triggering material flows into the display section and is there either directly visible or can be made indirectly visible, for example. By experiencing a chemical reaction with a detection substance located there. Thus, the analyte could undergo a color change when it comes in contact with the triggering agent. Of course, it is also advantageous in this embodiment, when the display section comprises a kind of viewing window. In particular, in the described embodiment, but also in other cases, it is advantageous if an absorber for receiving fluid trigger material is arranged in the display section. This absorber can z. B. be a kind of sponge or granules, which absorbs a liquid. In this way, it can be prevented, for example, in the case of a display process based on thermal expansion, that the liquid flows back into the triggering section when the temperature drops. Again, it is conceivable that the absorber additionally reacts with the triggering material to produce, for example, a color change.

It is particularly preferred to produce the absorber from a hygroscopic foam material. The term "hygroscopic" in the context of the usual terminology of physics describes the property of being able to absorb liquid from the environment, with particular attention being paid to the fact that the release material is absorbed by the foam in a liquid state to clarify that the term "hygroscopy" is used in accordance with the strict terminology of the natural sciences and, in particular, is not to be confused with hydroscopy, which refers only to the absorption capacity of water. Rather, the absorption capacity of liquids is generally meant, the hygroscopy is crucial in terms of the liquid triggering material and is in the foreground. The hygroscopic properties of the foam ensure that the release substances present in the region of the triggering section are transported in the liquid state even in the presence of small amounts up to the display section. The presence of the liquid triggering agent in small amounts thus leads to the desired indicator effect. Another suggestion Zug can be seen in that the preparation of this indicator body can be done by simply filling the foam material, which adapts automatically to the shape of the display section.

Furthermore, in order to promote liquid transport from the trigger section to the display section, a fluid trigger capillary may be disposed between the trigger section and the display section. Such a capillary can consist of one or more capillaries, can be passed through the liquid, for example. In the manner of a thermometer. A reservoir for the liquid triggering substance located in the triggering section can in this case be in direct contact with the capillary ladder. The display process can be carried out by outflow of triggering material from the Kapillarleiter in the display section. In addition, however, it is also conceivable, for example, for a small piston element located in the capillary conductor to be driven by the expanding triggering material in the direction of the display section and finally ejected into the latter.

In order to achieve an improved display in cases where the triggering material is less noticeable in color, it is preferable for the indicator body to contain an indicator substance which is arranged such that it can be transported by the fluid triggering substance into the display section. The indicator substance may in this case be in the form of granules, powder or the like, it may even be suspended in an initially liquid triggering substance. It is also conceivable that an initially solid triggering material melts first and then flushes the indicator substance with it when flowing into the display section. The indicator substance may be located in the triggering section, near the triggering material, but it is also conceivable that it is located between the triggering section and the indicator section, so to speak, on the intended flow path of the triggering substance. Control over how long the sterilization temperature has been exceeded is possible by, for example, controlling the amount of triggering material that has entered the display section. For this purpose, it is preferable that the display section includes a reservoir having a viewing window and a content mark. Through the viewing window, the contents of the reservoir - eg the flowed in triggering material - are observed. The essence mark may consist of a single stroke indicative of a target fill that is achieved only with a sufficiently long sterilization time.

According to a further embodiment of the invention, a bimetallic element can be arranged in the triggering section, by the deformation of which, when the sterilization temperature is exceeded, the indicator operation can be triggered. Here, the bimetallic element could be part of a simple mechanical display device, for example. In the way that a kind of pointer is attached to the bimetallic element. A return of the pointer to its starting position at the end of the thermal treatment can be prevented that this is held by a simple locking device.

Preferably, the bimetal element is part of a valve, via which an inflow path for a fluid in the display section can be released. In other words, said valve initially blocks the fluid inflow path, for example, a fluid release material, and opens after the sterilization temperature has been exceeded. This variant can be combined with the fact that the fluid expands under heating. In cases where the sterilization temperature is chosen well above the necessary minimum temperature of 56 ° C, ie, for example. 80 ° C further control of the duration of the heating is not necessary, as already described above. In other cases, it is advantageous if the display process is delayed.

This means that a certain amount of time elapses between the actual triggering, starting from the triggering section, and the actual display process, which is ideally at least 30 minutes. One way to achieve this is to arrange a delay element between the trigger section and the display section, by means of which the movement of a fluid towards the display section can be slowed down. The said fluid may in this case be an above-described triggering substance which is already present in fluid form from the beginning or is first solid and then melts. For example, the retarding element may be a material through which the fluid diffuses only slowly. Also, a finely porous material can be used, that is penetrated only gradually by the fluid. It may also be a kind of closure of a channel, wherein the closure is provided with one or more small openings that allow only a small volume flow of fluid to pass.

According to a further advantageous embodiment, the indicator body comprises a spring-loaded display mechanism with a securing element, wherein melting of the securing element can be achieved by exceeding the sterilization temperature. This means that the securing element consists of a material which melts in the region of the sterilization temperature. The fuse element blocks the display mechanism in a solid state. When it melts, the display mechanism is released and changes its position due to the spring loading. typical Schieß the spring action will exist from the beginning, ie there will be a bias of the spring. However, it is also possible here to realize this with a bimetal spring, which in turn builds up a voltage only when heated above the sterilization temperature.

In order to make the use of the indicator body even safer and to further prevent manipulation, it is preferred that the indicator body has an individual marking in the display section. This can typically be a kind of serial number, by which the individual indicator body is individually marked. In this way it is possible to determine the origin of the indicator body and, for example, to associate it with a thermal sterilization procedure whose protocol can be viewed.

As already mentioned, the indicator body may have different shapes, wherein at least for the parts that are to be inserted into the recess of the structural element, a shape with approximately constant cross section is advantageous. The part comprising the display section, on the other hand, may have a larger cross section. It therefore corresponds to an advantageous embodiment that the indicator body comprises a head comprising the display section and a shank which tapers the trigger section and is tapered relative to the head. Thus, in the basic structure, an indicator body is obtained, which tapers from the display section with a larger diameter towards the release section, so that the basic shape of a cone is obtained. The term "basic shape" means that the radial cross section of the cone or truncated cone does not necessarily have to be circular and can deviate explicitly from it. The intended recess can also widen to the edge, so that the head can be completely or partially sunk. The head can in principle have any cross-section, for example round or polygonal. The same applies in principle for the shaft, in which case a round cross section is preferred, since this corresponds to an easily produced recess with a round cross section. As already mentioned, the shaft can also carry, at least in parts, a thread by means of which the indicator body is screwed into the recess.

The manufacture and handling of the installation of the indicator body are particularly simple if both the triggering section and the indicator section are accommodated inside a sleeve of preferably cylindrical shape, ie the shape of a hollow cylinder. Thus, the indicator body can be completely prepared outside the transport pallet and bring in the manner of a plug into the recess. Thus, the indicator body during handling d. H. completely protected during transport but also during insertion into the recess.

In the case of the presence of a connecting material in the above-described sense, it is necessary that the sleeve is provided with at least one outwardly guided connecting channel, so that the connecting substance has the opportunity to pass from the interior of the sleeve to the outside in the recess. Only then will the desired safeguard against manipulation become effective.

Furthermore, according to the invention, a transport pallet is made available. This comprises at least one structural element made of wood or wood-based material, as well as a few at least partially inserted into a recess of the structural element indicator body comprising a arranged inside the structural element trigger portion and arranged on an outer side of the construction element display section, wherein a display operation with a visible change in the region of the display section can be triggered by exceeding a predetermined sterilization temperature in the trigger section is which change is irreversible to a subsequent below the sterilization temperature.

The inner dimensions of the recess may be at least partially greater than the outer dimensions of the indicator body, so that there are gaps or cavities, in the z. B. can incorporate an above-mentioned compound.

The transport pallet may also comprise a plurality of construction elements each having a recess or a construction element having a plurality of recesses, wherein an indicator body is arranged in each of the recesses.

Preferred embodiments of the transport pallet according to the invention correspond to the above-described embodiments of the Indian body.

Finally, the present invention provides a production method for a transport pallet. In the method, an indicator body is provided, comprising a trigger section and a display section, wherein a display operation with a visible change in the region of the display section can be triggered by exceeding a predetermined sterilization temperature in the region of the trigger section, which change is irreversible to a subsequent below the sterilization temperature. Furthermore, a design element of the transport pallet made of wood or wood material is provided, which construction element has a recess for at least partially receiving the indicator body.

The recess may in this case either already be formed during the production process of an element consisting of wood-based material or it may be subsequently produced by drilling, milling or the like. Furthermore, the indicator body is at least partially inserted into the recess, wherein the triggering section is arranged in the interior of the construction element and the display section is arranged on an outer side of the construction element.

It should be understood that the manufacturing process may include other steps that substantially correspond to the assembly of a transport pallet known in the art. This refers to the manufacture and assembly of other construction elements, such as boards and blocks.

Preferred embodiments of the production method correspond to the embodiments of the indicator body according to the invention shown above.

Details of the invention are explained below with reference to an embodiment with reference to the figures. Hereby shows:

FIG. 1 shows a perspective view of a first embodiment of an indicator body according to the invention; Figure 2 is a sectional view of the indicator body of Figure 1 in a pad of a transport pallet;

3a shows a sectional view of a second embodiment of an indicator body according to the invention in one

Log of a transport pallet before a heat treatment; a sectional view of the indicator body of Figure 3a after a heat treatment.

FIG. 1 shows in schematic form a perspective view of a first embodiment of an Indian body 1 according to the invention. The indicator body 1 is of essentially rotationally symmetrical design and has a head 5 and a shank 4, which adjoins the latter and is adjacent thereto. On the front side of the head 5, a viewing window 6 is arranged, via which a reservoir 7 located in the head 7 can be observed. The head 5 essentially forms a display section 3, while the end facing away from the head 5 of the shaft 4 forms a trigger section 2. The outer wall of the head 5 and the shaft 4 are made in the present example of thin sheet metal.

Figure 2 shows in a sectional view the indicator body 1 in a recess 51 of a pad 50, which is part of a transport pallet. The illustration corresponds to the state before a heat treatment of the pallet. The inner dimensions of the recess 51 correspond essentially to the outer dimensions of the indicator body 1, although a rear area of the recess 51 the length of the shaft 4 exceeds, so that there is a cavity 52 behind the shaft 4. Outwardly, the recess 51 expands to accommodate the head 5, which is thus completely submerged. Inside the shaft 4, two separate chambers 8, 10 are arranged. A substantially conical first chamber 8 is opened to the cavity 52 and filled with a first granules 9, which was pressed into the first chamber 8. The first chamber 8 is concentrically surrounded by a second chamber 10, which contains a second granule 1 1. The two granules 9, 1 1 may optionally consist of the same material. Each of the mentioned granules 9, 11 may be admixed with a pulverulent dye for better coloring. The second chamber 10 is open to the reservoir 7 located in the display section, wherein in a frontal closure 12 only small connecting channels 13 are provided to the reservoir 7. The granules 1 1 can not pass through the connecting channels 13 in its solid form. The melting temperature of the two granules 9, 1 1 is in the range of a designated sterilization temperature of 56 ° C. When the pallet is subjected to thermal sterilization, a temperature gradient forms inside the block 50, the edge regions heating up earlier than the inner regions. Here, the indicator body 1 forms only a negligible thermal bridge, since it is on the one hand small dimensions (eg 50 mm long, 20 mm head diameter, shaft diameter 10 mm), on the other hand, the air located within the reservoir 7 and the granules 9, 1 1st Only poorly heat conduct the metal sheet, from which head 5 and shaft 4 are made, has a very small cross-section. Thus, the triggering section 2 reaches the sterilization temperature almost simultaneously with the immediately adjacent material of the pad 50. The parts of the graph nearest to the reservoir 7 Nulats 1 1 may start to melt earlier as they reach a similar temperature earlier. Molten granules, following the profile of the chamber 10, flow to and through the communication channels 13. Due to the very small cross section of the connecting channels 13, the flow through is very slow. At the viewing window 6 a (not shown) mark is attached, which corresponds to that level of liquefied granules 1 1 in the reservoir 7, which is achieved when a time scheduled for the sterilization period (eg. 30 minutes) has expired.

By exceeding the sterilization temperature and the first granules 9 is liquefied, which, also following the profile of the first chamber 8, flows into the cavity 52. In this case, on the one hand, a certain binding effect between the indicator body 1 1 and the recess 51 can develop, but in particular it is possible to determine, at least by removing the indicator body 1 1, whether liquefied (and subsequently again solidified) granulate 9 is located in the cavity 52. This represents a proof that in fact the entire pallet with the indicator body 1 located therein (and not only the indicator body 1 separately) has been heated. It is also possible to provide a barrier with small connecting channels in the area of the opening of the first chamber 8 to the cavity 52, as a result of which the outflow of the liquefied granulate 9 can also be slowed down. This may allow additional control of the duration of the thermal treatment.

FIGS. 3 a and 3 b show a further embodiment of an indicator body 21 according to the invention. The outer shape thereof corresponds substantially to the first embodiment 1 illustrated in FIGS. 1 and 2. Thus, this also has a head 25 and a shaft 24 which substantially the outer shape of the corresponding elements 4, 5 of Fig. 1 have. In this case, the head 25 once again forms a display section 3, which also here comprises a reservoir 27 which is closed to the outside by a viewing window 26. However, a number of connecting channels 32 are provided which extend radially from the reservoir 27 to the outside of the head 25. A recess 51 of the pad 50, in which the indicator body 1 is located, has an inner diameter in the region of the head 25 which is slightly larger than the outer diameter of the head 25. The shank 24 is essentially formed by a sleeve element 33 as well as a closure part 34 closing it to a side facing away from the head 25. In the region of the closure part 34, a prestressed spiral spring 28 is arranged, which acts on a piston 29. Within the sleeve member 33, a chamber 30 is provided, which acts as a cylinder for the piston 29. In the state shown in Fig. 3a before a heat treatment, the chamber 30 is filled with a solid wax 31, which effectively forms a closure of the chamber 30 and thus prevents expansion of the piston 29. The melting temperature of the wax 31 corresponds to an intended sterilization temperature of 80 ° C.

If a thermal sterilization of the transport pallet is carried out, the wax 31 melts from the outside inwards until finally the part located in the triggering section 22 adjacent to the piston 29 melts as well. As a result, the piston 29 is released and pushes the liquefied wax 31 through the chamber 30 in front of him. In this case, the wax 31 first enters the reservoir 27, wherein it can be seen through the viewing window 26. In the course of the wax 31 is pressed by the pressure of the piston 29 through the connecting channels 32 until it enters the space between the head 25 and recess 51. This state is shown in Fig. 3b. Consequently is here also at least detectable by removing the indicator body 21 that the thermal treatment has taken place while the indicator body 21 has been located within the place 50. Possibly. For example, even small portions of the wax 31 may emerge at the front between the head 25 and the adjacent wall of the pad 50 and thus be immediately visible.

In the illustrated embodiments, the shaft 4, 24 of the respective indicator body 1, 21 is constructed purely cylindrical and smooth. It can be introduced by inserting or, if necessary, by light impact with a rubber hammer in the intended recess 51. Of course, it is also conceivable to provide a threaded shaft or a shaft which has no round but angular shape.

List of reference numerals, 21 indicator body

, 22 Trigger section

, 23 Display section

, 24 shank

, 25 head

, 26 viewing windows

, 27 Reservoir

first chamber

first granules

0 second chamber

1 second granules

2 closure

3, 32 connecting channel

8 spiral spring

9 pistons

0 chamber

1 wax

3 sleeve element

4 closure part

0 logs

1 recess

2 cavity

Claims

claims

Indicator body (1, 21) for objects made of wood, in particular a transport pallet, for at least partial arrangement in a recess (51, 52) of a construction element (50) of the transport pallet

a trigger section (2, 22) for placement inside the structural element (50) and

a display section (3, 23) for placement on an outer side of the structural member (50),

wherein a display operation with a visible change in the region of the display section (3, 23) can be triggered by exceeding a predetermined sterilization temperature in the region of the trigger section (2, 22), which change is irreversible in relation to a subsequent undershooting of the sterilization temperature.

Indicator body according to claim 1, characterized in that in the triggering section (2, 22) and optionally in the display section (3, 23) an initially liquid protein, in particular protein, which denatures when the sterilization temperature is exceeded, introduced.

Indicator body according to claim 1, characterized in that the triggering section (2, 22) contains a solid triggering substance (1 1, 31), wherein melting the triggering substance (1 1, 31) and at least partially flowing out into the display section (1) by exceeding the sterilization temperature ( 3, 23) can be reached. Indicator body according to claim 3, characterized in that the triggering material is a dye, at least in the molten state of at least one component.

Indicator body according to claim 3, characterized by a spring-loaded piston (29) which is blocked by the fixed triggering material (31) and is adapted to move after

Melting of the triggering substance (31) to press this in the display section (3, 23).

Indicator body according to Claim 3, characterized by a spring-loaded piston (29) whose spring is embedded in the solid release substance (31) in the compressed state and which presses the piston (29) into the display section (3, 23) after the release substance has melted.

Indicator body according to one of the preceding claims, characterized in that the triggering section (2, 22) contains a solid connecting substance (9, 31), wherein melting of the connecting substance (9, 31) and at least partial outflow into the recess ( 51, 52) is reachable.

8. Indicator body according to one of the preceding claims, characterized in that the triggering section (2, 22) a fluid Contains triggering material, by the expansion of which, when the sterilization temperature is exceeded, the display process can be triggered.

9. indicator body according to claim 7, characterized by a the

Expansion of the fluid release substance restricting blocking element, which is destructible by a pressure increase of the fluid release material when the sterilization temperature is exceeded.

10. Indicator according to one of the preceding claims, characterized in that the triggering substance consists of two mutually reactive components which are separated by a blocking element, which upon reaching the sterilization temperature, for. B. can be eliminated by melting, wherein by reaction of the two (or more) components, a foaming process takes place.

1 1. Indicator body according to claim 7 or 8, characterized in that the indicating process can be triggered by flowing the fluid release substance into the display section (3, 23).

12. Indicator body according to one of claims 3 to 1 1, characterized in that in the display section (3, 23) an absorber for receiving fluid release material is arranged.

13. Indicator body according to claim 12, characterized in that the absorber consists of hygroscopic material, preferably of foam material.

14. Indicator body according to one of claims 3 to 13, characterized in that between the trigger section (2, 22) and display section (3, 23) a Kapillarleiter for fluid release material is arranged.

15. Indicator body according to one of claims 3 to 1 1, characterized by an indicator substance, which is arranged such that it can be transported by the fluid release material in the display section (3, 23).

16. Indicator body according to one of claims 3 to 12, characterized in that the display section (3, 23) comprises a reservoir (7, 27) with a viewing window (6, 26) and a Inhaltsmarkie tion.

17. Indicator body according to one of the preceding claims, characterized in that in the trigger section (2, 22) a bimetallic element is arranged, by the deformation of which is exceeded when the sterilization temperature of the display operation can be triggered.

18. Indicator body according to claim 14, characterized in that the bimetal element is part of a valve, via which a flow path for a fluid in the display section (3, 23) is releasable.

19. Indicator body according to one of the preceding claims, characterized in that between the trigger section (2, 22) and the display section (3, 23) a delay element (12) is arranged, by which the movement of a fluid to the display section is slowed down.

20. Indicator body according to one of the preceding claims, characterized by a spring-loaded display mechanism with a securing element, wherein a melting of the securing element can be achieved by exceeding the sterilization temperature.

21. Indicator body according to one of the preceding claims, characterized in that the display section (3, 23) has an individual marking.

22. Indicator body according to one of the preceding claims, characterized by a display section (3, 23) comprising the head (5, 25) and a trigger section (2, 22), with respect to the head (5, 25) tapered shank (4, 24).

23. Indicator according to one of the preceding claims, characterized in that the recess for receiving the display section, in particular of the head, widens so far towards the edge, that the display section, in particular the head is partially or completely lowered.

24. Indicator body according to one of the preceding claims, characterized in that the triggering section (2, 22) and display section (3, 23) are housed inside a preferably cylindrical sleeve.

25. Indicator according to claim 24, characterized in that the sleeve is provided on the front side with a connecting channel.

26. Transport pallet, comprising

at least one of wood or wood material existing construction element (50), and

an indicator body (1, 21) at least partly inserted in a recess (51, 52) of the construction element (50), which has a release section (2, 22) arranged inside the construction element (50) and an exterior part of the construction element (50) arranged display section (3, 23),

27. Manufacturing method for a transport pallet, at least with the steps: Providing an indicator body (1, 21), comprising a triggering section (2, 22) and a display section (3, 23), wherein a display operation with a visible change in the region of the triggering section (2, 22) exceeds a predetermined sterilization temperature Display section (3, 23) is triggered, which change is irreversible to a subsequent below the sterilization temperature,

Providing a construction element (50) of the transport pallet consisting of wood or wood material, which construction element (50) has a recess (51, 52) for at least partially accommodating the indicator body (1, 21),

at least partially inserting the indicator body (1, 21) into the recess (51, 52), wherein the trigger section (2, 22) inside the construction element (50) and the display section (3, 23) on an outside of the construction element (50) is arranged.