EP1080807A1 - Method for manufacturing an object from at least two connected components - Google Patents

Abstract

The production process involves making one part (14) as a semi-finished product (30) of plastically deformable material, with a recess (32) into which the anchor (22) of the other part (12) projects. The semi-finished product is then placed in a mold and is hot or cold-deformed so that it is positively and/or non-positively connected to the anchor.

Description

The invention relates to a method for producing one from at least two Parts of composite object, at least part of one plastically deformable material made of precious metal or a precious metal alloy and the part to be connected to it consists of base metal.

In a known manufacturing process for silverware the individual cutlery parts such as spoons, forks, serving cutlery and. a. by Stamping and forging or stamping made of sheet metal and are therefore all solid. In contrast, the knives consist of one Stainless steel manufactured blade that is integrally molded Shaft or tang connected with a silver handle. The booklet consists of two half-shells soldered together to form a cavity. The The blade and the handle are soldered together using an in filled in the tacky cavity of the hardenable putty in which the shaft of the Blade is positioned. After the putty has hardened, the shaft is the Blade permanently anchored in the handle.

The manufacture of the table knife with silver handle described above is extremely labor intensive and leads due to a large share of wage costs high production costs. By forging and / or embossing from silver sheet molded-out half-shells are on the inside along the edges of the shells coated with soldering flux and silver solder powder, put together, positioned with wires or clamps and with each other at elevated temperature soldered. As the solder seam is clear compared to the adjacent silver plate visible, the booklet has to go into a further operation after trimming are still galvanically silvered.

The invention is therefore based on the object of a method of the beginning to create the type mentioned, which is the connection of at least two parts enables in a simple manner. In particular, the method should allow Knives, letter openers, containers such as bowls and cups with feet, candlesticks and the like two-part or multi-part objects made of different Materials, especially objects with a precious metal part, in to manufacture simple manufacturing steps.

To achieve the object according to the invention, that of the plastic deformable material existing part as a blank with a recess is present and from the part to be connected to the blank into the Insertable anchoring part protrudes, the anchoring part inserted into the recess, the blank inserted into a mold by Cold and / or hot massive forming pressed into the mold and with the Anchoring part is non-positively and / or positively connected.

The method according to the invention enables part of the shape to be shaped object to be manufactured and its connection with another Part in a single operation. The cost of making a knife with silver booklet can be compared to the cost of one according to the state of The technology of the manufactured knife even without a solid booklet Consideration of the increase in value of the knife due to the increased precious metal content be kept much lower.

Especially with tableware, care should be taken that at the same time cutlery held in one hand, e.g. Fork and knife, about are equally difficult. Special care should also be taken with a knife be there in supporting the booklet in the area of the transition to the blade is approximately balanced, so that the knife when resting on The edge of the plate does not tip over and generally lies well in the hand.

Depending on the thickness of the booklet, the weight of the booklet may be necessary to reduce. This reduction in weight can preferably be achieved that the shaft of the blade, i.e. the knife, in relation to the total depth the recess is kept relatively short. Generally speaking the recess comprises a first recess part for receiving the anchoring part protruding from the part to be connected to the blank and one adjoining the first recess part second recess part. The second recess part contains a medium whose density is less than the density of the noble metal or the noble metal alloy.

The density of the medium in the second recess part is preferably less than about 5 g / cm ³ . The medium can be gaseous, liquid or solid.

For most applications, it should be sufficient if the medium of Ambient air in the manufacturing process corresponds. If a solid medium is selected, this can be made from an insert made of plastic or from a Light metal or a light metal alloy, in particular made of aluminum, Magnesium, lithium, titanium or one based on one of these metals manufactured alloy exist.

The advantages of the method according to the invention are evident in the production of objects in which the one from the plastically deformable Material existing part or the blank and the part to be connected to it Part consist of different metals. The term "different Metals "also includes alloys on the same or a different one Base as well as identical metals or alloys in different Heat treatment conditions.

The method for producing articles is particularly preferred made of silver, gold or platinum in combination with stainless steel.

In a particularly preferred variant of the method according to the invention massive forming takes place - in contrast to "sudden" forming - under a time-changing pressure.

The blank can be formed using the generally known solid forming processes such as forging or pressing in dies in warm and / or cold state. However, the blank is preferably extruded, especially formed by cold extrusion or by wobble pressing.

For the production of luxury items with a precious metal part with a fine design The surface is particularly the tumble cold forming suitable procedure.

Tumble cold forming or tumbling presses means shaping of a cold metal blank between two die halves, the upper one Die is moved with a wobbling thrust pin and - in contrast to conventional cold extrusion - the forming force only on a partial surface of the workpiece acts. The material is "rolled in" into the die. The friction and the power requirement are low, which makes it amazing high degrees of deformation can be achieved, resulting in high strength Strain hardening leads. Another feature of wobble pressing is the good one Formation of complex parts, which means the production of finely designed surfaces enables. Compared to the conventional methods, the use of noble metals be reduced very significantly.

Fig. 1

die Seitenansicht eines Tafelmessers;

Fig. 2

die Rückenansicht des Tafelmessers von Fig. 1;

Fig. 3

die Seitenansicht der Klinge des Tafelmessers von Fig. 1;

Fig. 4

die Rückenansicht der Klinge von Fig. 3;

Fig. 5

die Seitenansicht des Heftes des Tafelmessers von Fig. 1;

Fig. 6

die Rückenansicht des Heftes von Fig. 5;

Fig. 7

den Längsschnitt durch eine Halbschale zur Herstellung des Heftes von Fig. 5 nach deren Linie I-I nach dem Stand der Technik;

Fig. 8

einen Rohling zur Herstellung des Heftes von Fig. 5;

Fig. 9

die Seitenansicht des Heftes entsprechend Fig. 5 mit angedeutetem Umriss des Rohlings von Fig. 8;

Fig. 10

die Rückenansicht des Heftes entsprechend Fig. 6 mit angedeutetem Umriss des Rohlings von Fig. 8.

Fig. 11

die Seitenansicht eines anderen Heftes entsprechend Fig. 9.

Further advantages, features and details of the invention result from the following description of preferred exemplary embodiments and from the drawing; this shows schematically in

Fig. 1

the side view of a table knife;

Fig. 2

the rear view of the table knife of Fig. 1;

Fig. 3

the side view of the blade of the table knife of Fig. 1;

Fig. 4

the rear view of the blade of Fig. 3;

Fig. 5

the side view of the booklet of the table knife of Fig. 1;

Fig. 6

the back view of the booklet of Fig. 5;

Fig. 7

the longitudinal section through a half-shell for producing the booklet of Figure 5 along the line II of the prior art.

Fig. 8

a blank for producing the booklet of Fig. 5;

Fig. 9

the side view of the booklet corresponding to Figure 5 with an outlined outline of the blank of Fig. 8.

Fig. 10

6 with the outlined outline of the blank of FIG. 8.

Fig. 11

the side view of another booklet corresponding to FIG. 9.

A table knife 10 shown in FIGS. 1 and 2 comprises a blade 12 and a booklet 14. The back 18 opposite a cutting edge 16 the blade 12 and the surface of the booklet 14 are with decorative elements 20 in the form of linear elevations and / or depressions.

The blade 12 of the table knife 10 is made, for example, of stainless steel Steel, booklet 14 made of silver or other precious metal. The structure of two different materials inevitably require an at least two-part Structure of the table knife 10 with a corresponding connection of Blade 12 and booklet 14 serves as an anchoring part for the blade 12 in booklet 14 3 and 4 a molded onto the blade 12 shaft 22, which in the Knife longitudinal axis x has different cross-sectional dimensions, so that the blade 12 does not move even if the connection is loosened can be easily detached from booklet 14.

According to the prior art, the booklet 14 shown in FIGS. 5 and 6 from two half shells 24 shown in FIG. 7, formed from sheet metal, by soldering the shell edges 26 made as a hollow body. Anchoring the The shaft 22 of the blade 12 in the booklet 14 is made by inserting the shaft 22 into the cavity of the booklet 14 filled with a hardenable putty 28 previously known type of connection is indicated in Fig.5.

The booklet 14 shown in Figures 9 and 10 is from a shown in Figure 8 Blank 30 produced by massive forming. The blank 30 has one in the later knife longitudinal axis x arranged bore 32, its diameter D essentially about the largest diameter of the shaft 22 of the Blade 12 corresponds and its length L is at least the length of the shaft 22 having.

As mentioned above, the external shaping and surface design takes place of the booklet 14 by means of a massive forming process, the shaft 22 of the Blade 12 is previously inserted into the bore 32 of the tack blank 30. During the solid forming in a die, the mold is filled through Flow of the material under a time-changing pressure. Simultaneously with the design of the outer surface of the booklet 14 on the The mold wall of the die flows around the shank material 22 positive and non-positive, which in turn leads to a significant reduction in the material used of the precious metal.

In the example shown, the longitudinal section of the shaft 22 is permanent Anchoring in issue 14 limited by wavy lines. Other conceivable anchoring elements are, for example, arranged transversely to the longitudinal direction of the shaft circumferential teeth, grooves, indentations or recesses.

The booklet 14 shown in FIG. 11 corresponds to the booklet shown in FIG. 9 with the exception that the shaft 22 of the blade 12 only protrudes into a first part 34 of the bore 32, while the part 36 of FIG Bore 32 is filled with a medium 38, in the present case with ambient air. The first recess part 34 has a length I ₁ which corresponds approximately to the length of the shaft 22. In the present example, this length I ₁ corresponds approximately to half the length I _{2 of} the second recess part 36.

At this point it should also be mentioned that the blank 30 is made, for example a cylindrical section of a solid solid rod produced by deep drawing can be. In this procedure, the recess 32 can without a cutting drilling process can be produced.

The method according to the invention is not based on the exemplary embodiments shown limited, but is suitable for the production of countless others two or more parts of assembled objects.

Claims (11)

Method for producing an object (10) composed of at least two parts (12, 14), wherein at least one part (14) consists of a plastically deformable material made of noble metal or a noble metal alloy and the part (12) to be connected to it consists of base metal ,
characterized in that
the part (14) consisting of the plastically deformable material is in the form of a blank (30) with a recess (32) and an anchoring part (22) which can be inserted into the recess (32) from the part (12) to be connected to the blank (30) protrudes, the anchoring part (22) inserted into the recess (32), the blank (30) inserted into a mold, pressed into the mold by cold and / or warm massive forming and force and with the anchoring part (22) / or is positively connected. A method according to claim 1, characterized in that the recess (32) a first recess part (34) for receiving the with the blank (30) to be connected part (12) of the anchoring part (22) and one adjoining the first recess part (34) comprises second recess part (36), and that the second recess part (36) contains a medium (38) whose density is less than that Density of the precious metal or the precious metal alloy. A method according to claim 2, characterized in that the density of the medium (38) in the second recess part (36) is less than 5 g / cm ³ . A method according to claim 2 or 3, characterized in that the medium (38) is gaseous, liquid or solid. A method according to claim 4, characterized in that the solid medium (38) from a plastic insert or from a light metal or a light metal alloy, in particular made of aluminum, magnesium, Lithium, titanium or from one based on one of these metals Alloy. Method according to one of claims 1 to 5, characterized in that that the precious metal is silver, gold or platinum and the precious metal alloy a minimum of 333/1000 shares of silver, gold or platinum having. Method according to one of claims 1 to 6, characterized in that that the base metal is stainless steel. Method according to one of claims 1 to 7, characterized in that that massive forming under a time-changing pressure he follows. Method according to one of claims 1 to 8, characterized in that that the blank (30) is hot and / or cold in by forging or pressing Dies is formed. A method according to claim 9, characterized in that the blank (30) by extrusion, in particular by cold extrusion, or by Tumble presses are formed. Application of the method according to one of claims 1 to 10 for production of knives, letter openers, containers such as bowls and cups with foot part, candlesticks and the like two-part or multi-part objects.

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