DE102010036663A1 - Component e.g. side lattice and food carrier, for indicating temperature of e.g. extension guide in furnace chamber, has reversible indicators and irreversible indicator for controlling temperature - Google Patents

Abstract

The component e.g. running rail (4), stopper (10) and guard diaphragm, has reversible indicators and an irreversible indicator for controlling temperature. The reversible indicators comprise a cover in the temperature range of about 40 to 90 degree C, where the cover is formed with a change in temperature less than 15 degree C. The irreversible indicator displays changes in temperature above 250 degree C. The reversible and irreversible indicators exhibit different color changes at different temperatures. An independent claim is also included for a method for manufacturing a securing component.

Description

The invention relates to a component for a fitting and / or a household appliance according to the preamble of claim 1 and a method for producing a component according to the preamble of claim 15 and a household appliance and a kiln.

Pull-out guides for high-temperature applications are already known. These are u. a. used in ovens with pyrolysis cleaning function. Since pull-out guides with a non-stick coating in pyrolysis operation of the oven (at over 500 ° C) may be damaged, the drawer slides are removed from the oven before pyrolysis and cleaned separately. When removing the pull-out guides shortly after using the oven and before cleaning the pyrolysis, the end user pays attention to the still hot heating coils in the upper part of the oven, but often fools at the temperature of the pull-out guides because of the already less hot oven interior.

On the basis of measurements on the temperature distribution by means of thermo cameras after switching off the oven, a particularly high temperature in the area of the drawer runners could be determined.

This is u. a. on the heat storage capacity of solid components of the pullout guides. So cool other furnace segments in the furnace interior, such. B. furnace walls and baking trays faster due to the low material thickness with a large surface area than the pullout guides.

It is therefore an object of the present invention to provide a component for a fitting and / or a household appliance, in particular for an oven or a pull-out guide for high-temperature applications, which enables safe handling and visual control.

It is a further object of the invention to provide an optimized method for producing a component.

The invention solves this problem by a component having the features of claim 1 and a method for producing a component having the features of claim 15.

According to the invention, a component for a fitting and / or a domestic appliance, in particular for an oven or for a pull-out guide for high-temperature applications, has a reversible and / or irreversible indicator for temperature control.

By using reversible temperature control indicators, the end user is warned of the still hot surface of the component. Reversible indicators are indicators which, under the influence of temperature, undergo a chemical or physical state change, for example a phase transformation, and return to an initial state when a starting temperature is reinstated.

Irreversible indicators in the area of the pull-out guides provide proof of improper use. For example, it is known that the majority of non-stick coatings are not compatible with pyrolysis or lose their non-stick properties at temperatures above 350 ° C. Therefore, the end customer is advised to disassemble the corresponding drawer runners prior to pyrolysis. If this is not done, this improper use can be proven by irreversible indicators. In this case, irreversible indicators permanently change their chemical or physical state when a minimum temperature is exceeded.

The component is preferably designed as a running rail, a plug and / or a protective cover of a pullout guide, to protect the pullout guide from contamination. This is advantageous because these components of the drawer slide can be easily perceived by a viewing window of a oven door or when opening the oven door. In this case, the reversible indicator can be applied particularly advantageously on the surface of the removable protective cover and warn the end user of the overheated pull-out guide. For the visibility of the indicator in case of contamination of the surface, it is sufficient to clean the protective cover instead of the entire drawer guide.

It is advantageous if the reversible indicator has an envelope, for example as a color change, in the temperature range of 40-90 ° C, preferably 50-70 ° C and the envelope at a temperature change of less than 40 ° C, preferably less than 15 ° C takes place. This allows the pullout guide to be removed by hand from an oven. In addition, waiting times during cooling are reduced by a relatively sharp transfer point.

It is furthermore advantageous if the irreversible indicator indicates temperature changes above 250 ° C., preferably above 300 ° C., since at these temperatures an oven is in pyrolysis operation. If pull-out guides are still in the oven at these temperatures, the indicator will indicate this improper use.

For displaying a plurality of temperature ranges, preferably between 40-80 ° C, it is advantageous if the indicator is a mixture of several indicator substances. The indicator fabrics have various envelopes, for example color changes. This color change can be caused inter alia by changing the bond distances, for example metal-oxygen distances or central atom-ligand distances, in the crystal lattice.

Alternatively, an influencing of these binding distances by matrix substances can take place. Such a matrix material may for example be a polysiloxane, which is embedded in Pb ₃ O _4. By embedding Pb ₃ O ₄ in different matrix substances and which are applied in several layers in sections on the component, the temperature range of the color change of the indicator can be varied.

In order to ensure a material-saving use of the indicator material, the indicator is preferably applied in sections or at points on the component.

Most preferably, the indicator is an indicator which indicates changes in temperature by a color change, so that the temperature of the component is visually detectable prior to contact or to prove improper use.

For a quick and easy installation of the pullout guide, it is advantageous if the indicator is a character or symbol for the mounting side of the pullout guide in the oven. This may be indicated, for example, by the design of a color indicator as a large "R" or "L" in the front half of the track of the pullout guide.

In an advantageous embodiment variant, the component has at least one first layer with the indicator and, above this first layer, a wear layer which protects the component and the layer with the indicator against scratches.

The irreversible indicator advantageously has at least two colored layers which are color-different from one another. At least one of the two layers, preferably a polymer layer with colored pigments, has a melting point of 250-600 ° C., preferably 300-450 ° C. When this melting point is exceeded, the color pigments diffuse into the second layer and thus irreversibly change the color of both layers.

The indicator is advantageously a lead oxide, preferably Pb ₃ O ₄ . Pb ₃ O ₄ , but also PbO, are known for their reversible phase transitions between two modifications. When using Pb ₃ O ₄ at temperatures above 550 ° C for conversion to PbO. Thus, the mixed-valent Pb ₃ O _{4 is} both a reversible indicator in the temperature range below 500 ° C and can also be used as an irreversible indicator.

It is also advantageous if a comparison segment or a layer of color pigments for matching the color of the indicator at room temperature is arranged on the component in a section in which there is no coating with indicator. Thus, Pb ₃ O ₄ , which is light orange in the cooled state, be arranged next to a comparison segment which also has light orange color pigments.

The indicator is arranged in a variant embodiment as a sticker on the component. As a result, already finished components that are already in use can be subsequently provided with an indicator.

• A Formgebung des Bauteils durch Biegen und/oder Stanzen;
• B Aufbringen eines Farbindikators auf das Bauteil und Beschichten des Bauteils mit einer Nutzschicht; und
• C Sintern unter Zuhilfenahme der Färbung des Farbindikators als Prozessgröße im Sinterprozess.

According to the invention, a method for producing a component for a fitting, in particular for a pull-out guide for high-temperature applications, comprises the following steps:

• A shaping of the component by bending and / or punching;
• B applying a color indicator to the component and coating the component with a wear layer; and
• C sintering with the aid of the coloring of the color indicator as a process variable in the sintering process.

On the basis of the coloring of the color indicator as a process variable, a control of the sintering temperature and / or the sintering time can take place.

This is particularly advantageous in the sintering process of inorganic-organic hybrid polymers, preferably with formation of an SiO ₂ useful layer. Here, the optimized effect of heat promotes the reaction of the hybrid polymers to form a scratch-resistant wear layer.

The component is used according to the invention in a household appliance, in particular an oven.

Unlike indicators for pans or hotplates, where the end user should be informed about the optimal cooking or cooking temperature, when using the component in the oven, the indicator is used to determine the temperature at which the component has reached approximately room temperature, or at a safe contact of the component is possible.

In an alternative embodiment, a SiO ₂ coated drawer slide with indicator for temperature control in a kiln can be used. In this case, a Seger cone is used in addition to the temperature determination. This standard DIN cone is slowly heated in the kiln. As soon as the cone tip of the 5 cm test cone is completely overturned, the cone temperature is reached. This temperature can be preset to 1500 ° C, 1600 ° C, 1700 ° C, 1800 ° C or 1900 ° C depending on the material and geometry of the cone.

A component according to this document for a fitting and / or a household appliance, for example, a component for a hinge, a drawer slide, a handle, an oven, a heat drawer, a grill, a microwave, etc. be. A component for a household appliance, for example, may be a side rail or a food support.

The invention will be explained below by means of an embodiment with reference to the accompanying drawings. They show:

1 - 3 several views of an embodiment of a component according to the invention, which is designed as a fitting in the form of a pullout guide.

4 View of the pullout guide of the 1 - 3 in an oven, and

5 View of a pullout guide with a protective cover

6 schematic representation of a layer structure of an irreversible temperature indicator layer

In the following, an exemplary structure of a drawer slide according to the invention is described in more detail.

A pullout guide 1 includes a guide rail 2 , which can be fixed to a side rail in an oven, a side wall of a baking oven or a furniture body. At the guide rail 2 is a middle rail 3 over rolling elements 6 movably mounted. The middle rail 3 serves for the storage of a running rail 4 , For storage of the rails 2 . 3 and 4 are on the guide rail 2 and the running track 4 in each case at least two, in the exemplary embodiment, three raceways 9 for rolling elements 6 educated. The rolling elements 6 are on a Wälzkörperkäfig 7 kept as a unit. Furthermore, at the middle rail 3 a total of at least four careers, in the embodiment six tracks raceways 8th for rolling elements 6 formed, each having at least two raceways 8th the guide rail 2 and at least two careers 8th the track 4 assigned.

For fastening the pullout guide 1 on a side rail of a oven are two brackets 5 on the guide rail 2 established. Other fastening means or attachment points can on the guide rail 2 be provided.

The guide rail 2 , the middle rail 3 and the track 4 are provided with a scratch-resistant and lubricious surface coating. The surface coating is at least partially provided with a reversible indicator for temperature control. The indicator is preferably arranged as a first layer on the component and consists of lead oxide (Pb ₃ O ₄ ) embedded in a silicone resin. The discoloration under the influence of temperature varies from light orange to dark red. Over this first layer, a wear layer may preferably be disposed of PEEK, PFA, PTFE, SiO ₂ or an inorganic-organic hybrid polymer.

Alternatively or additionally, on or on one of the running rail 4 fixed stopper 10 an indicator for temperature control glued or coated. The middle rail 3 , is completely inside the drawer slide 1 arranged when the running rail 4 in the retracted position.

The indicators are preferably applied to visible areas of the drawer slide.

In the 1 to 3 is an overhang with three rails 2 . 3 , and 4 shown. A version with at least three rails as a full extension is also conceivable. It is also possible, the pullout guide as a partial extension with only two rails (without the middle rail 3 ) or with more than three rails.

The term component in the special area of the drawer guides are preferably the running rail 4 and the stopper 10 captured, which are visible in the oven.

4 shows the attachment of the pullout guide 1 in the interior of a baking oven 17 , Here are on the plug 10 with dark red Pb ₃ O ₄ marking "R" and "L", 14A and 14B applied, which point to the mounting side of the pullout guides in the furnace chamber.

Alternatively or additionally, for indicators with several color changes, especially for mixtures of several indicator substances or in an indicator substance in multiple matrix substances multi-colored lettering are made possible.

So a lettering "Hot" z. B. with an indicator substance in a first matrix substance having a color change at 70-80 V and a lettering "Cold" with the indicator substance in a second matrix substance having a color change at 40-50 V.

Additionally or alternatively, preferably on the side facing the furnace interior of the pullout guide in the front half of the track 4 a mark 15 arranged.

For visual comparison, in a particularly preferred embodiment, a comparison segment or comparison section 16A . 16B of orange-red color pigments in the vicinity of the portion or marks with the indicator layer 14A . 14B . 15 arranged, which is unchanged orangered orange even at higher temperatures.

This allows the end user to visually adjust, with color difference that the pullout guide is still hot or color difference between comparison segment 16A . 16B and markings 14A . 14B . 15 in that the drawer slide has already cooled down.

In a further preferred embodiment, as in 5 shown, a protective cover 12 over two fasteners 13 on the pullout guide 1 appropriate. In this case, the protective cover at least partially on the reversible indicator. The protective cover 12 Can be applied to existing pullout guides, so that an easy installation of the protective cover 12 by the end user is possible.

The protective cover 12 is preferably formed strip-shaped and covers the space between the running rail 4 and the guide rail 2 in which without the protective cover 12 During the cooking process in the oven fat spills or other food contaminants could reach, which reduce the running characteristics of the drawer slide.

In a particularly preferred embodiment, the guide rail 4 and / or the plug 10 the pullout guide 1 provided with an irreversible indicator which irreversibly discolored at temperatures above 300 V, while on the protective screen 12 a reversible indicator is applied.

Thus, the consumer is warned even with improper use of the drawer slide in pyrolysis at 500 V by the reversible indicator from the risk of burns, at the same time receives the manufacturer in possible complaints information about the improper use of the drawer guide by the irreversible indicator.

It is particularly advantageous if the indicator points or sections in the front half of the drawer guide preferably on the running rail 4 or the protective cover 12 is applied so that the end user can estimate the temperature of the pullout guide on the basis of the coloring without much effort.

The production of a drawer guide according to the invention is described by way of example below.

Individual components of the pullout guide are formed by punching and bending.

Subsequently, the individual components can be at least partially coated and mounted or preferably mounted before coating to a finished drawer guide and at least partially coated after final assembly.

The coating is for example a PFA, PTFE or PEEK coating. Alternatively, an inorganic-organic hybrid polymer coating, as described in the patent application DE 10 2009 044 340.1 discloses is applied to the pullout guide or the component of the pullout guide.

The coating is preferably carried out by applying a suspension of the coating material in a solvent and then heating, so that the solvent evaporates and only the coating material remains on the surface.

A scratch-resistant and lubricious surface is formed by the subsequent sintering process.

When heating and during the sintering process, a temperature monitoring is necessary, since in the sintering furnace possibly local temperature centers are formed, which can locally lead to damage to the coating. For this purpose, reversible or irrelevant indicators can be used, which enable visual monitoring, in particular of the sintering process. Alternatively, the process monitoring can also be detected and evaluated by a measuring sensor.

At the same time, the optimum sintering temperature can be set, so that a particularly good thermal compression of the coating on the surface of the component of the drawer slide is achieved.

In the following, possible reversible and irreversible indicators for temperature control are described in more detail, which are preferably used in components, in particular for pull-out guides.

Reversible indicators include VaO ₂ , WO ₃ , ZnO, Ag ₂ [Hgl ₄ ], Hgl ₂ and especially Pb ₃ O ₄ . The color change of the mixed-valent lead oxide takes place by phase transformation with changes in the lead-oxygen bond distances.

Pb ₃ O ₄ can also be used as an irreversible indicator in furnaces with pyrolysis technology. Above 550 ° C, the transformation into red PbO, which differs from the orange-red Pb ₃ O _{4 takes place} .

Irreversible indicators are u. a. Substances which undergo changes in color due to melting processes.

A layer sequence for an indicator is, for example, in 6 shown The indicator in 6 comprises a multilayer structure of two differently colored layers 22 . 24 an irreversible indicator 20 and a wear layer 21 ,

The wear layer 21 ensures the preferred surface properties, preferably scratch resistance and non-stick properties against grease and dirt deposits.

In the underlying first layer 22 a polymer layer is arranged, which colored agents or color pigments 23 For example, TiO ₂ pigments are added. Due to the white color of these TiO ₂ pigments, this segment of the coating appears white to the end user. The polymer layer 22 may for example be formed from an optionally modified polyester or polyamide having a melting point above 300 ° C.

The second layer below 24 is for example a polymer layer which other colored agents or color pigments 25 as the first layer. For example, the second layer has soot particles which form the second layer 24 color black.

This second layer 24 and their color is initially not perceived by the end user. However, the outside temperature exceeds the melting point of the polymer of the first and / or second layer 22 and 24 , so there is a diffusion of both layers and the color pigments contained therein 23 and 25 so that the color of the coating changes for the viewer or the end user.

Thus, in the present embodiment, when the temperature exceeds 300 ° C., an irreversible color change from white to gray-black takes place.

The layer or layers 22 and 24 with the indicator preferably have a layer thickness of 0.5-2 .mu.m. The color pigments within the layers have a preferred average particle size of between 10-500 nm. Color pigments have this 23 and 25 irreversible indicators of particularly advantageous diffusion over a preferred average particle size of 10-50 nm.

In addition to the preferred indicators which indicate temperature changes by color change, electrical devices can also be used, in particular in the case of irreversible indicators. For example, a wire can be attached to a component pull-out guide. This wire burns at too high temperatures through (Efensicherung) and are in the connection a signal, for example to the oven as a warning of the risk of possible damage to the pullout guide on, whereupon this shuts off the pyrolysis. In the same way, an electrolytic capacitor can generate a signal which, for example, by polarity reversal suffers a defect at temperatures above 400 ° C, which is detectable.

LIST OF REFERENCE NUMBERS

1

pull-out guide

2

guide rail

3

middle rail

4

runner

5

clip

6

rolling elements

7

Rolling Element

8th

raceways

9

raceways

10

Plug

11

retaining bolt

12

shield

13

fastener

14A

mark

14B

mark

15

mark

16A

Comparative segment

16B

Comparative segment

17

oven

20

Irreversible indicator

21

wear layer

22

First shift

23

color pigment

24

Second shift

25

color pigment

26

component

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009044340 [0058]

Claims (18)

Component ( 4 . 10 . 12 ) for a fitting and / or a household appliance, in particular for an oven ( 17 ) or for a drawer slide ( 1 ) for high-temperature applications, characterized in that the component ( 4 . 10 . 12 ) a reversible and / or irreversible indicator ( 14A . 14B . 15 . 20 ) for temperature control. Component ( 4 . 10 . 12 ) according to claim 1, characterized in that the component ( 4 . 10 . 12 ) a running track ( 4 ), a stopper ( 10 ) and / or a protective shield ( 12 ) a pullout guide ( 1 ), to protect the pullout guide ( 1 ) from contamination. Component ( 4 . 10 . 12 ) according to claim 1 or 2, characterized in that the reversible indicator ( 14A . 14B . 15 ) has an envelope in the temperature range of 40-90 ° C, preferably from 50-70 ° C. Component ( 4 . 10 . 12 ) according to claim 3, characterized in that the envelope takes place at a temperature change of less than 40 ° C, preferably less than 15 ° C. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the irreversible indicator ( 20 ) Indicates temperature changes above 250 ° C, preferably above 300 ° C. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the indicator ( 14A . 14B . 15 . 20 ) in sections on the component ( 4 . 10 . 12 ) is applied. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the indicator ( 14A . 14B . 15 . 20 ) is a mixture of several indicator substances and / or is an indicator substance in different substrate materials. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the indicator ( 14A . 14B . 15 . 20 ) has different color changes at different temperatures. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the indicator ( 14A . 14B . 15 . 20 ) a character or mark ( 14A . 146 ) for the mounting side of the pullout guide ( 1 ) is formed in a furnace. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the component ( 4 . 10 . 12 ) at least a first layer with the indicator ( 14A . 14B . 15 . 20 ) and over this first layer a wear layer ( 21 ) for the protection of the component ( 4 . 10 . 12 ) and the first layer is protected from scratches and contamination. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the irreversible indicator ( 20 ) at least one first colored layer ( 22 ) and a second colored layer ( 24 ), which are color-different from the first colored layer ( 22 ), wherein at least one of the two layers ( 22 . 24 ) has a melting point of 250-500 ° C, preferably 300-450 ° C. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the indicator ( 14A . 14B . 15 . 20 ) is a lead oxide, preferably Pb ₃ O ₄ . Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that on the component ( 4 . 10 . 12 ) in a indicator-free section a comparison segment ( 16A . 16B ) with color pigments to match the color of the indicator ( 14A . 14B . 15 . 20 ) at room temperature. Component ( 4 . 10 . 12 ) according to one of the preceding claims, characterized in that the indicator ( 14A . 14B . 15 . 20 ) as a sticker on the component ( 4 . 10 . 12 ) is arranged. Method for producing a component ( 4 . 10 . 12 ) for a fitting, in particular for a pull-out guide ( 1 ) for high-temperature applications, characterized by the following steps: A shaping of the component ( 4 . 10 . 12 ) by bending and / or punching; B application of an indicator ( 14A . 146 . 15 . 20 ) on the component ( 4 . 10 . 12 ) and. Coating of the component ( 4 . 10 . 12 ) with a wear layer ( 21 ); where the indicator ( 14A . 14B . 15 . 20 ) has different colors at different temperatures and C sintering with the aid of the coloring of the indicator ( 14A . 14B . 15 . 20 ) as a process variable in the sintering process. Household appliance, in particular oven ( 17 ) characterized in that in or on the household appliance, in particular in the oven space, at least one fitting ( 4 . 10 . 12 ) is arranged according to one of the preceding claims. Kiln, characterized in that in or on the kiln a component ( 4 . 10 . 12 ) is arranged according to one of the preceding claims. Pullout guide ( 1 ), characterized in that the pullout guide a component ( 4 . 10 . 12 ) according to one of the preceding claims.

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