Pressing method for producing coins
The coining method efficiently produces high relief and high quality coins by preforming reliefs on a coin blank and restriking with coining dies, achieving enhanced relief and quality with simplified production.
Patent Information
- Application Number
- JP2025109293
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-07-02
- Filing Date
- 2025-06-27
- Publication Date
- 2026-01-19
AI Technical Summary
Existing methods struggle to produce coins with high relief and high quality efficiently.
A coining method involving preforming reliefs on a coin blank using milling and restriking with coining dies, allowing for high relief and high quality coins to be produced with minimal material movement during the process.
The method enables the production of coins with extremely high raised relief on both sides, enhancing counterfeit resistance and quality, while simplifying the production process.
Smart Images
Figure 2026008992000001_ABST
Abstract
Description
[Technical Field]
[0001] This invention relates to coining methods for producing coins. Summary of the Invention [Problem to be solved by the invention]
[0002] The object of the present invention is to produce coins of extremely high relief and high quality. [Means for solving the problem]
[0003] The above technical problem is solved by the subject matter of the independent claims. Technically preferred embodiments are the subject matter of the dependent claims, the description and the accompanying drawings.
[0004] According to a first aspect, the aforementioned technical problem is solved by a coining method for producing coins, comprising the steps of preforming a coin's relief and restriking said relief using a coining die. The method achieves the technical advantage of being able to produce coins with a high degree of relief and with extremely high quality. Because the relief motif is already present in the coin blank, no significant material movement occurs during the subsequent coining process.
[0005] According to a technically preferred embodiment of this coining method, the relief is preformed by a milling method, which achieves the technical advantage, for example, that the relief can be preformed very efficiently.
[0006] According to another technically advantageous embodiment of this coining method, a first relief is preformed on one side and a second relief on the opposite side, thereby achieving the technical advantage that, for example, coins with extremely high raised relief on both sides can be produced.
[0007] According to another technically preferred embodiment of this coining method, a first relief is restriked on one side using a first coining die and / or a second relief is restriked on the opposite side by a second coining die, thereby achieving the technical advantage that, for example, coins with extremely high raised relief on both sides can be efficiently produced.
[0008] According to another technically preferred embodiment of this coining method, the relief has a height of at least 100% of the thickness of the coin blank, preferably at least 150% or at least 200% of the thickness of the coin blank, thereby achieving technical advantages such as the production of highly counterfeit-resistant coins.
[0009] According to another technically advantageous embodiment of the coining method, the reliefs are pre-formed in a sheet material, which can be sized so that a coin can be pre-formed from a plurality of reliefs arranged side by side in the sheet material, thereby achieving the technical advantages of, for example, simplifying the creation of the reliefs and enabling multiple coin blanks to be produced in a fast and simple manner by a single cutting operation of the sheet material.
[0010] According to another technically preferred embodiment of the coining method, the first and / or second side of the sheet material is face milled, which achieves technical advantages, for example, in that irregularities or inconsistencies in the sheet material can be eliminated, thereby improving the coining quality.
[0011] According to another technically advantageous embodiment of this coining method, the coin blanks are cut out from sheet material, thereby achieving technical advantages such as simplified production of the coin blanks.
[0012] According to another technically preferred embodiment of this coining method, the preformed relief is heated prior to restriking. Heating the blank increases the malleability of the coin blank, thereby achieving technical advantages, such as the ability to create higher raised profiles by hot forming and further improving the quality of the coin.
[0013] According to another technically preferred embodiment of this coining method, the relief, coin blank or plate is made from gold, silver, copper, platinum, non-ferrous metals or alloys, thereby achieving the technical advantage that, for example, highly suitable materials are used for the production of coins.
[0014] Embodiments of the present invention are illustrated by the accompanying drawings and the detailed description set forth below. [Brief explanation of the drawings]
[0015] [Figure 1] FIG. 1 is a schematic diagram of a coining process. [Figure 2] FIG. 1 is a schematic diagram of a method for producing a coin blank with a preformed relief. [Figure 3] FIG. 1 is a schematic diagram of a method for producing a coin blank using face milling. [Figure 4] FIG. 1 is a block diagram of a coining process for producing coins. DETAILED DESCRIPTION OF THE INVENTION
[0016] An overview of the coining process is shown in Figure 1. First, reliefs 105-1 and / or 105-2 are preformed on one or both sides of a coin blank 103. The reliefs 105-1 or 105-2 protrude from the coin blank 103. The reliefs 105-1 or 105-2 are three-dimensional molded representations of a motif. The coin blank 103 is, for example, a circular disk. The reliefs 105-1 and 105-2 can be preformed into the required three-dimensional shape by a cutting process, for example, milling.
[0017] The coin blank 103 with the reliefs is then restrike-formed using a coining method. To this end, the coin blank 103 with pre-formed reliefs 105-1, 105-2 is placed between both coining dies 107-1 and 107-2. The pre-formed reliefs 105-1, 105-2 are restrike-formed by the coining dies 107-1 and 107-2, and the coin 100 acquires its final shape. To this end, the coining dies 107-1 and 107-2 have recesses for post-processing and shape adjustment of the reliefs 105-1, 105-2.
[0018] 2 shows an outline of a method for producing a coin blank 103 having preformed reliefs 105-1 and / or 105-2. First, a sheet of material 111 is used as a basis for producing the coin blank 103. The sheet of material 111 has a thickness of, for example, 3 mm and is formed from gold, silver, copper, platinum, a non-ferrous metal, or an alloy. The sheet of material 111 may be large enough to produce multiple coin blanks 103 from it. In this case, multiple reliefs 105-1 are milled side-by-side on the sheet of material 111.
[0019] At multiple locations within the plate 111, three-dimensional reliefs 105-1 are preformed into a desired shape, for example by CNC machining, which shape approximately corresponds to the shape of the reliefs 105-1 after the subsequent coining process. The reliefs 105-1 and 105-2 can be preformed on one or both sides of the plate 111. The resulting three-dimensional coin blank 103 represents the subsequent model. The reliefs 105-1 arranged side by side are spaced apart from one another within the plate 111.
[0020] Once the reliefs 105-1 and 105-2 have been pre-formed in the sheet material 111, the individual coin blanks 103 are cut out from the sheet material 111. This can be done by cutting out the intermediate region 113 using a groove cutter. The coin blanks 103 are, for example, circular and have a diameter of 11 mm to 120 mm. The coin blanks 103 are then ready for restriking.
[0021] FIG. 3 shows an outline of a method for producing a coin blank 103 by face milling. A sheet of material 111 is used as a base for producing the coin blank 103. First, one or both sides of the sheet of material 111 are face milled to a depth of, for example, about 0.1 mm so that the sheet of material 111 has a uniform thickness. To prevent burrs, the face milling is performed in a spiral pattern. Ensuring the sheet of material 111 has a uniform thickness can improve the quality of the coining process.
[0022] After that, a plurality of reliefs 105-1 are milled out side by side from the face-milled plate 111. The plate 111 is cut in an area 115 opposite the relief 105-2 of the plate 111. In this case, the area 115 opposite the relief 105-2 is cut evenly by a milling tool, thereby forming a circular recess having a surface corresponding to the surface of the opposite relief 105-2.
[0023] Once the relief 105-2 has been pre-formed in the sheet material 111, the individual coin blanks 103 are cut out from the sheet material 111. This can be done by using a groove cutter to cut out the intermediate region 113. The coin blanks 103 are then, for example, circular and have a diameter of 11 mm to 120 mm.
[0024] A block diagram of the coining process for producing coins is shown in Figure 4. The coining process comprises step S101 of preforming the reliefs 105-1, 105-2 for the coin 100. The coin blank 103 can be structurally adjusted to achieve perfect coining (angle, shape, shadow).
[0025] Then, in step S102, the reliefs 105-1 and 105-2 are restriked by coining dies 107-1 and 107-2. This coining method allows the production of coins with extremely high, raised reliefs 105-1 and 105-2. The height of the reliefs 105-1 and 105-2 is, for example, 200% of the thickness of the coin blank 103.
[0026] The three-dimensional coin blank 103 is coined using, for example, PP (polished plate) quality coining dies 107-1, 107-2. Up to 200% relief per side allows for maximum detail and mirror-quality coining. The shape can have 200% of the thickness of the coin blank 103 on one or both sides.
[0027] The thickness of the coin blank 103 is calculated using the following formula: X=Rg*4 / (Sg*π*D*D) where X is the thickness of the coin blank, Rg is the nominal weight of the coin blank, Sg is the specific gravity of the material, and D is the diameter of the coining die 107.
[0028] Nominal weight: 31.1g, specific gravity: 0.0105g / mm 3, the diameter is 38.35 mm, the thickness X of the coin blank 103 is 2.565 mm. Therefore, a relief of 200% of the thickness of the coin blank 103 has a height of 5.13 mm. A relief of 400% of the thickness of the coin blank 103 has a height of 10.26 mm.
[0029] All of the features described and illustrated in relation to individual embodiments of the invention can also be the subject of the invention in various combinations, whereby simultaneous advantageous results are achieved.
[0030] All method steps may be performed using apparatus suitable for performing each method step. All functions performed by the feature of interest may be method steps in this method.
[0031] The scope of protection of the present invention is defined by the appended claims and is not limited by the features described or shown in the description. [Explanation of symbols]
[0032] 100 coins 103 Coin Blank 105 Relief 107 Coining type 109 sides 111 Board material 113 Intermediate area 115 areas
Claims
1. A step (S101) of preforming reliefs (105-1, 105-2) of a coin (100); Step (S102) of restriking the reliefs (105-1, 105-2) using coining dies (107-1, 107-2).
1. A coining process for producing a coin (100) comprising:
2. 2. Coining method according to claim 1, wherein the reliefs (105-1, 105-2) are preformed by a milling method.
3. 3. Coining method according to claim 1 or 2, wherein a first relief (105-1) is preformed on one side (109-1) and a second relief (105-2) is preformed on the opposite side (109-2).
4. 4. A coining method according to any one of claims 1 to 3, wherein a first relief (105-1) is restriked on one side (109-1) using a first coining die (107-1) and / or a second relief (105-2) is restriked on the opposite side (109-2) by a second coining die (107-2).
5. 5. A coining method according to any one of claims 1 to 4, wherein the reliefs (105-1, 105-2) have a height of at least 200% of the thickness of the coin blank (103).
6. A coining method according to any one of claims 1 to 5, wherein the reliefs (105-1, 105-2) are preformed in the sheet material (111).
7. 7. A coining method according to any one of claims 1 to 6, wherein the first surface (109-1) and / or the second surface (109-2) of the sheet material (111) is face milled.
8. 8. A coining method according to claim 6 or 7, wherein the coin blank (103) is cut from a sheet of material (111).
9. A coining method according to any one of claims 1 to 8, wherein the preformed reliefs (105-1, 105-2) are heated before restriking.
10. 10. The coining method according to any one of claims 7 to 9, wherein the relief (105-1, 105-2), the coin blank (103), or the plate (111) is made of gold, silver, copper, platinum, a non-ferrous metal, or an alloy.