Laser System Solutions for the Minting Industry
Laser Systems in the Minting Industry
The laser is a universal tool in many respects in the coin-producing and medal-producing industry:
- Laser digitizing
- 3D laser engraving
- Micro laser engraving
- Frosting and surface texturing
- Circumference stamping
Areas of Application in the Minting Industry
“Fortuna Redux” – the world’s first coin in a cylinder design.
3D laser engraving demonstrated in this highly complex application. “Fortuna Redux” is a joint project between ACSYS and the Polish Mint in Warsaw. All of the die tools have been produced using the PIRANHA by ACSYS.
The video shows the journey of this project from the initial idea to the completion of the arguably most extraordinary coin that has ever been produced. This coin was born out of a passion for unique design – the design of a 3-sided coin.
More precise, better, more economical – nothing less will do. Machine solutions by ACSYS are characterized by maximum exactness, precision and repeatability. Laser digitizing is based on the technology of conoscopic holography and allows the creation of extremely precise digital 3D data of a wide range of very different surfaces, plaster models, dies or actual coins and medals.
The resulting 3D file can be used for production and reproduction and can easily be processed in the CAD software. The advantages of this contact-free method are high speed and small measuring grid distances. Perfect accuracy of 2 µm can be achieved with the replaceable lens system. Conoscopic holography is a patented process and offers the greatest precision and repeatable accuracy over a wide range of applications.
The image on the right shows the design of the ACSYS laser scanner. The laser beam is used for creating a light dot on the object that is to be measured. Part of the light, which is reflected from this light dot, is captured by the sensor’s lens and falls on the conoscopic crystal. There the incoming light rays are initially separated into partial rays, before being reunited into the original rays after their exit from the crystal. This creates an interference pattern, which is captured using a CCD sensor and then electronically evaluated.
The image on the right shows the basic principle of 3D laser engraving.With 2.5D and 3D laser engraving, the surface of the workpiece is removed to a certain depth in a software-controlled process. The material is evaporated layer by layer so that the desired structure gradually appears.
High-precision depth removal in three dimensions is made possible with the AC LASER Software and laser machining centers by ACSYS.
2.5D and 3D engraving differs from deep engraving in the extent of software-controlled depth removal. This way, predefined edge angles for dies can be realized as easily as complex three-dimensional surface textures / structures on coin minting stamps.
3D laser engraving and excellent processing times
3D laser engraving allows the creation of a three-dimensional surface structure on a wide range of very different materials. Especially in the minting industry, ACSYS machining centers are combined with the AC-LASER Software in order to ensure maximum efficiency. All process steps – from the creation of the file to the output at the laser – are perfectly coordinated and provide the user with an intuitive workflow.
Frosting and surface texturing
Another application is effective selective “frosting” of polished molded tools, for example stamping dies for coins or medals. Unlike the process, in which paint or a similar protective coating is first applied to the die and then manually removed from certain areas that are to be frosted under the microscope using a scalpel before irradiation, frosting with a laser machining system requires considerably less effort. The entire process time is significantly reduced and the result no longer depends on an employee’s steady hand.
The energy of the laser can be precisely adjusted, thereby allowing the creation of a uniform and soft surface structure. The areas that are to be frosted can comfortably be defined on screen with the mouse using a high magnification. Also, lasers open up entirely new possibilities in terms of design, since – in addition to traditional frosting with the aim of producing a matt surface – an unlimited number of other textures with interesting visual effects can be applied.
Selective frosting of dies for coins or medals is much more efficient using a laser machining system as compared to the conventional process. The entire process time is significantly reduced and consistent quality is guaranteed.
A process that has been developed by ACSYS for the exact replication of the “sandblasting” effect when laser frosting.
Manufacturing of stamping dies for authenticity certification
ACSYS laser systems with μ-functionality are able to engrave minute contours and 3D structures on a die. The LAS – Live Adjust System HD dual-camera preview offers the unique option of creating the punching template directly on the die blank on the screen. The following image shows the superb quality and high resolution of the LAS optics and the entire system. The hallmarks are conventionally “punched” using steel dies. The dies are manufactured in different sizes for objects from small pieces of jewelry to large silver plates.
The excellent combination of high-precision preview and μ-precision laser machining allows shorter production times and manufacturing cycles of high-quality punching stamps. The laser can also be used for processing entirely new materials. Machining centers by ACSYS in combination with the AC-LASER Software offer maximum efficiency. All process steps – from the creation of the file to the output at the laser – are perfectly coordinated and provide the user with an intuitive workflow.
Direct punching on coins and jewelry (direct hallmarking)
The ACSYS in-house hallmark for test purposes. Direct punching is a way of authenticity certification directly on the respective object using a laser. The laser allows a highly forgery-proof direct punching process on coins and jewelry using specific parametrization. The specifically set steel profiles can be individually adjusted at any time, thereby ensuring the item’s authenticity. This method is particularly suited for sensitive objects and hollow items, which otherwise would get damaged or distorted by a conventional punching process.Subsequent “finishing” of workpieces is unnecessary because of the direct laser marking, laser engraving and 3D laser engraving processes. Unfortunately, for confidentiality reasons, we are unable to show you “real” lasered hallmarks. These marks have specific parameter settings of the laser, which means that they are clearly identifiable.
OPR – Optical Part Recognition
The optical part recognition enables the fully automated processing of non-palletized loose parts. The software recognizes the position and rotational angle of the workpieces and marks or engraves in the previously trained location. In this example, 180 components were automatically marked on a surface of 580 x 485 mm² in a single working step.
ODC – Online Depth Control
For depth engraving and 3D engraving,the material is removed down to μm-level, ensuring high-precision results. The ODC module measures the actual engraving depth contact-freeand controls the exact target depth of the laser.
Free-form surfaces can also be sampled and digitized with the ODC module, making them easy to process.
Ultra-High-Resolution Cameras and Dual-Camera Preview
The LAS – Live Adjust System camera set-up module by ACSYS makes working with the laser very efficient.
2D and 3D graphics as well as text can be edited directly on the workpiece using camera-based editing. A dual-camera solution provides an additional ultra-high-resolution preview of the workpiece straight through the laser beam.
The ACSYS Laser Software Suite enables highly efficient data handling. When processing 3D data, in particular, any weaknesses in the underlying programming of a software will most certainly show. The AC-LASER has been specifically developed and optimized for the area of 3D processing.
You will achieve outstanding results with the powerful modules of the AC-LASER Software. The graphical user interface allows users to implement each request within the shortest possible time period, without having to compromise with regard to design or quality. Intelligent image processing functions reduce setup times to a minimum.