DE1454210A1 - Enamelled cookware, roasting or baking utensils and processes for their manufacture - Google Patents

Description

WM F-SILITWERK GmbH. ΪΪ i e d 1 i η £ e η / 'W ü rtt.

Enamelled cookware, roasting or baking dishes and method of making it

The invention relates to a. Cooking, roasting or baking dishes. ' made of sheet steel of The surface is provided with a coating of one or more enamel layers. Furthermore betx-ΊίΤt üie invention a method for producing " position of such harnesses and a; to carry out this procedure suitable

2O98H / O1i51

-z-

In general, the enamel dishes for use on gas and coal stoves with βτπ <"1 are related Crockery base made to protect the floor area from the highly corrosive effects of the open Flame, especially to protect the gas flame. For enamel dishes for use on electrical appliances if, on the other hand, the outer surface of the floor is not enamelled, turned or sanded down, it will be used good heat transfer from the electric heating plate to the bottom of the crockery is guaranteed.

There are also so-called all-purpose enamel harnesses known, which can be used on electrical, gas and Coal stoves should be usable. In contrast to the special electric harnesses, these harnesses have no reinforced floor. The outer surface of this floor is not enamelled either, but mostly ground flat. This training has the following disadvantages:

The corrosive effect of burning Sulfur compounds produced by luminous gas lead to strong compounds after a relatively short period of use Corrugations on the unprotected outer surface of the bottom of the crockery, especially in the area of the gas flame ring, which can lead to a complete destruction of the bottom of the crockery.

2098U / Ö1S1

Perner is due to the thin sheet metal of the insulation floor; The heat distribution over the entire surface the bottom of the crockery poor. In the area of the overheated areas of the electric heating plate or Because of the gas flame, zones with a greatly increased temperature are formed on the inside of the bottom of the dishes from, .lie can cause the food to burn. Permanent deformations can also result or warping of the bottom of the dishes.

It has already been suggested to go through the bottom of the crockery after enamelling the crockery To remove the enamel coating from sandblasting and apply liquid metal to the metallically pure floor surface spray on - in order to obtain a top layer with favorable thermal conductivity. This procedure is however relatively expensive and results in a porous surface in which contaminants can easily settle can.

The aim of the invention is to produce an enamelled To create all-purpose utensils, which not only the Defects of the previously known enamel dishes eliminated, but also great technical and economic Has advantages.

209614/0151

The invention is essentially characterized in that the outer surface of the bottom of the crockery, possibly also a more or less large further portion of the crockery surface, bears a coating layer consisting of a mixture, compound, fusion or similar combination of an enamel mass with at least one metal powder is a ^{particularly:....} suitable example has this aluminum powder proved the enamel layer, the metal-containing powder can be arranged on a Grundcmailschicht of the utensil base, but it can also be located directly on the steel sheet surface of the pot bottom in the latter · case, the metal powder is suitably If necessary, a metal powder in a suitable suspension can also be applied to an already-baked base or top enamel layer and connected to the same by baking or at least partially mixed Enamel slip containing metal powder or> -. ^; The Mutallpulversuspens.ion eg sprayed cold with an enamel spray gun common in enamelling technology. The burned-in coating can be treated, for example, by means of a rotating steel wire brush, which gives a shiny metallic surface, especially when using aluminum powder.

2O98U / 01S1

-s-

With the invention, an effective and permanent corrosion protection of the bottom of the crockery is first of all in a very simple and inexpensive manner. This increases the service life of the enamel dishes considerably. Furthermore, the presence of the Metal powder, which should have the highest possible thermal conductivity, a much better one Heat distribution over the entire surface of the crockery base achieved so that local overheating on the inside of the bottom of the dishes largely avoided will. As a result, you can use relatively small sheet metal thicknesses for the dishes without having to fear that the cooked or roasted food so easily burns locally as with the previously known all-purpose dishes. It also increases the risk of a Reduced warping of dishes bathing. It is particularly beneficial for the even distribution of heat the application of a top layer containing metal powder to a base enamel layer, because the latter then also acts as an insulating layer and brings about an even better heat distribution.

; Compared to the flame spray applied Metal plating requires the method according to

the invention a significantly lower cost

Work operations, technical facilities and resources. - ■. ".

20 * 814/0161. 'cad OBiöiNAL _

■ -6- ■ .._.- ■ ■ - ',, ■ -

In the drawing, the invention is illustrated schematically in various exemplary embodiments. . ,

Pig. 1 shows an enamelled steel crockery according to the invention in vertical section, while ₍

Fig. 2 to 6 enlarged cross-sections

Crockery base with different arrangements of base enamel and enamel metal powder show layers.

That shown in Fig. 1 as an embodiment Crockery consists of a pot-shaped body made of sheet steel with a crockery tray 1 and a side wall 2, The dishes can also have a pouring rim 3 have. Furthermore, on egg side wall 2 in the usual Way handles 4 be attached.

The crockery body is inside and outside with a Base enamel layer 5 and a top enamel layer 6 provided »Furthermore, the outer surface of the crockery base carries a top layer 7 or 7 * * which consists of one with Metal powder mixed or bonded enamel. According to Fi ^. 1 and 2 is the one from one email flow "

and a coating layer 7 consisting of a metal powder mixed in with it, applied to the base oil layer 5 of the dish oven 1. Referring to FIG. J5 constituting the coating layer 7 ^f of a base enamel and contained therein a metal powder which is applied directly to the bare metal surface of the pot bottom is "1.

According to FIGS. 4 and 5, the inner surface of the dishes, especially of a gas cooker used for frying, can be covered with a coating 7 bzif. 7 * made from a mixture of enamel or base enamel with metal powder. In this way, the favorable conditions for heat distribution can be improved even further. Accordingly, especially in large kitchen utensils, the entire outer surface of the utensil, ie also the outer side wall surface, can be provided with a coating layer J or 7 ^1.

It is also possible according to FIG. 6, a suspension of metal powder and Einern ScliViebemittel such as clay or the like. to be applied in a liquid to a burned-in base enamel layer 5 and burned in. A transition layer 7 ¹ of base enamel and metal powder is then obtained, which, with increasing distance from base enamel layer 5, merges into a cover layer 7 ″ that is more and more enriched with metal powder. The cover layer 7 ″ can consist almost entirely of molten metal on the surface. = _ ■ *

'209814/0161'

Surprisingly, it has been shown that the metal powder in all of the embodiments mentioned with the enamel mass during the baking process an intimate, firmly adhering connection or fusion enters into.

The metal powder is expediently made of a metal with high thermal conductivity and good durability against the corrosive effect of the hot gas flame manufactured. A metal has been found to be particularly suitable. powder made of aluminum or an aluminum alloy. But there is also the option of others Metal powder with appropriate properties such as-. Use copper or brass powder. Pener can Mixtures of two or more different types of metal powders to be used.

The metal powder used for mixing or embedding in the enamel should expediently be relatively fine-grained. For aluminum powder ₌ a grain size of 0.1 to 0.25 mm has proven to be favorable.

The enamel mass is expediently made from an enamel frit Manufactured with a high proportion of flux when the enamel-metal powder mixture is applied to a base enamel will. Such an enamel flow has the following composition, for example:

- .. 209814/0151 ■ - .-. OADORisJ & i ~

20 parts of feldspar 20 parts by weight of quartz flour 20 parts soda

ho parts by weight of borax dehydrated

This Eraailflufi is made with the following additions finely ground, which are only mentioned as an exemplary embodiment;

100 parts by weight of enamel flux (e.g. as stated above) 10 parts by weight of clay

0.6 parts by weight borax dev. 46 parts by weight of water

For example,> 00 weight parts of aluminum powder are then mixed into this enamel slurry, with ^ e ^ if necessary, a further amount of water was added in order to obtain an injectable mass.

The addition of aluminum powder or other suitable metal powder or metal powder mixtures can also be chosen smaller or larger depending on uen desired effects. For example, the mentioned Only about 200 parts by weight of metal powder can be mixed in with the enamel thickener, but you can add the additive also increase considerably, e.g. to 500, 750 or even 1000 weight parts. Possibly the lower and upper limits of the Metallpulverzusat ^ ea can also be moved further down or up.

209> U / 01S1 - - - _ ₁₀ .

With an enamel slip-metal powder mixture composed as above, for example as follows procedure

A basic enamel is first applied in the usual way to the bare metal surface of the steel dishes applied, dried and baked. Any known basic email can be used for this will.

The baked base enamel layer is then applied to the areas not to be treated according to the invention Place a cover enamel, e.g. of the usual type, on the inside and outside of the crockery. The rest Place, 'especially on the outside mustard pool of the At the bottom of the crockery, the enamel slip metal powder compound is applied, preferably sprayed, to the base enamel layer. Finally the Deekemail and the enamel slip-metal powder mixture dried and baked in one step.

_v If the enamel slip-metal powder mixture is to be applied directly to the metal surface, do you proceed as follows, for example?

'"' ■■■ ι- - ι

#Ur the production of the enamel slip is

in this case a basic email is used, welehö $

BAO OF

may have a commercial composition. The corresponding basic enamel granules are, for example, with the following additives and proportions pure ground:

100 parts by weight of base enamel 10 parts by weight of clay 7 parts by weight of quartzinehl h parts by weight of quartz sand 0.2 parts by weight of soda 0.4 part by weight of borax 0.15 part by weight of sodium nitrite 50 parts by weight of water

This basic enamel sealer is now again, for example, 300 parts by weight of aluminum powder or other suitable metal powder or metal powder mixtures mixed in, if necessary with the addition of more pus Liquid until an injectable mass is achieved. Here, too, can be added to metal powder smaller or larger analogous to the information above to get voted.

This Gruridemail metal powder mixture is at the desired places on the dishes, that is, preferably?, n the outer surface of the bottom of the dishes r. on the bare metal surface.

2098U / 0161

-12-

.bracht, preferably sprayed on, after a basic enamel of the usual type has previously been applied to the rest of the files on the inside and outside of the dishes. The base enamel and the base enamel mixed with metal powder / are then dried and baked in one operation. If necessary, xxs. on the layer of the usual. Basic enamel is followed by a standard deicemail layer, then dried and baked. At the same time, εαιοΐι could be applied again to the burnt-in base metal powder layer. Enamel metal powder can be applied, dried and baked.

Finally, there is also the possibility of first apply a basic enamel to the bare metal surface the usual way to apply, dry .and

will

bake, and then do the desired locations, in particular at the bottom of the cookware Aussenflache'des the baked base enamel is a mixture, suspension or the like. of "metal powder with one or more suspending agents such as clay is applied, preferably sprayed on, dried and baked. The following composition can be selected as the suspension, for example:

209814/0151

H54210

100 parts by weight of aluminum powder 15 parts by weight of clay
70 parts by weight of water

After the enamel-aluminum powder compound has been fired in the surface of the tableware is colored gray in the relevant areas. Duron easy sanding using a rotating steel wire brush or the like. can however a shiny metallic aluminum surface can easily be achieved.

The invention relates generally to the enamelled dishes and the method of manufacture same, but is not related to the preceding AusfUliruri [jsexamplei. · Limited ,, but includes all ■ Variants within the scope of the essential inventive concept, especially with regard to the AiB »mhl der / different mass components and their composition.

Expectations

-14-

2098U / 0151

Claims (1)

Claims 1. Enamelled cooking, roasting or baking utensils made of sheet steel, characterized in that at least vie outer surface of the crockery base (1), optionally also a more or less large further portion aor üusscren and / or inner Gesohirriioberi'läohe, a cover rail ( J, 7 ¹ ), which consists of a mixture, connection, fusion or similar combination of an enamel mass with at least one metal powder. 2. Tableware according to claim 1, characterized in that the metal powder consists of a metal with high thermal conductivity and good resistance to the corrosive effects of the hot gas flame. 3 crockery according to claim 1 and 2, characterized in that that the metal powder is made of aluminum or an aluminum alloy * 4. Crockery according to claim 1 to 3, characterized in that the metal powder consists of a mixture of aluminum powder and another metal powder such as copper or brass powder ¹ . 5. Crockery according to one or more of claims 1 to 4, characterized in that the enamel mass _s "~" * ~ 2098U / 0151 " -15- ^r . \ xs an enamel frit with a high flux coating is made. ■ 5. Crockery according to one or more of Claims 1 to H, characterized in that the enamel coating consists of a commercially available basic enamel. 7 · Gesehirr naeli a Odei ¹ more of claims 1 to 6, üiK.uroh jekennzeichnet, c! Ate the metal surface concerned of the pot bottom (1) and the harness (1, 2) has a base enamel layer (5) and above it a cover layer (7 ) r-.us of the Em el lines mixed with metal powder se ti ^v eq; t. ü. Dish NRCH one or more of claims 1 to 6, characterized jekemizciehnet that the metal surface concerned of Gesjhirrbodcns (1) and the harness (1, 2) immediately brought to lie bare Met aiii laugh :: uT coating layer (7 ¹⁾ from a base enamel mass mixed with metal powder 'j. Crockery, in particular roasting or baking dishes, according to one or more of claims 1 to 8, characterized in that the inner surface of the crockery (1, 2) or at least the bottom of the crockery (1) with a base enamel layer (5). arranged 2098U / 0161 . -16- ■ Cover layer (7) made of enamel mixed with metal powder or with a coating layer (7 ¹ ) made of a base enamel mixed with metal powder and applied directly to the bare metal surface. mass is provided. 10. A method for producing a harness according to one or more = of claims 1 to S $, characterized in that a base enamel is first applied to the bare metal surface , dried and baked, that then on the baked base enamel layer at the desired points on the inside and outside of the dishes - a cover enamel of the usual type on the outer surface and the enamel mass mixed with metal powder at the other points, in particular on the outer surface of the crockery base, and that · finally the cover enamel and the enamel-metal powder mixture are dried and baked. 11. A method for making a harness according to a or several eggs claims 1 to 9s characterized that directly on the bare metal surface in the desired places a basic enamel of the usual type and at the other points, especially on the outer surface of the outer surface of the crockery base cine base enamel mixed with metal powder on ^ ebrc.eht, geti-ueknet and " 9814/0151 BAD ORiO! I ^; : .- V ■ __,:. 145421Q is burned in. 12. The method according to claim 11, characterized in that that on the layer of the usual base enamel and possibly also on aie base enamel metal powder layer a top layer of enamel is applied, dried and baked. 1p. Method for producing a harness according to one or more of Claims 1 to 12, characterized in that that first a base enamel is applied to the bare metal surface, dried and baked whereupon the burned-in at the desired points, in particular on the outer surface of the crockery base Basic enamel a mixture, suspension or the like. of metal powder with suspending agent in water or the like. is applied, dried and baked. 14. The method according to any one of claims 10 to 1j5, characterized characterized in that the enamel or base enamel metal powder coating mass is sprayed on. Yj>. Coating compound for enamelled crockery according to one or more of Claims 1 to 9 *, characterized in that the compound consists of a mixture of Sraailschlioker and one or more metal powders consists. .__ _t 'ORIGINAL 209814/0151 -18- 16. Coating composition naoii claim 15, characterized in that that the mass of an enamel slip and a powder made of aluminum or an aluminum alloy. 17 · Coating compound according to claim 15 or 16, characterized in that that the metal powder or the aluminum powder has a grain size of 0.1 to 0.25 mm. 18. Coating mass according to one of claims 15 to 17 *, characterized in that the mass to 100 parts by weight of enamel flux or base enamel 100 to 1000, preferably approx. 250 to 750 parts by weight of aluminum powder or other suitable metal powder and optionally Additives such as clay, quartz powder, qualt sand, borax, soda, Sodium nitrate or the like. contains. WMP-SILITWERK GmbH, represented by: (Edmund F.EÖtner) Patent attorney 2098U / Q-1 & 1