Automation is what drives the industry of tomorrow and the case for automated marking machines is no different. The marking industry size was approximately $5966.9M in 2019, and is to grow at a CAGR of 4.1% during the forecast period 2020-2025. As companies increase production and reduce costs, automatic marking machines play an important role now more than ever. It is critical to their survival in the cut-throat world of business.
Conventional marking methods are not necessarily unreliable. Hand stamping tools are available in multiple modes. From hand-held metal punches to simple ink stamps, a vast array of tools is available to cater to user needs. However, there are several limitations to their usage. First and foremost is the limited volume they can cater to. A user will only be able to stamp a few items and human limitations reduce output capacity. The second factor is that of reliable repeatability. Conventional methods involve human input. Reliably repeating a process is not consistent with human nature. To err is human after all. Concerns of quality and accuracy are extensions of the points above.
To address these concerns and more, the marking industry responded by automating the process and building an array of tools for customers to choose from. For automation of manufacturing, quality control, and material handling processes, automatic marking systems play a pivotal role. Machines and systems receive individual production information from machine-readable data that customers mark on their products. This data is in use throughout the production line and supply chain. Identification data in the form of data matrix codes, QR codes, and bar code labels are in use to automatically control downstream manufacturing processes. Such is the world of ‘smart factories’.
Why We Need Automatic Marking Solutions
Marking usage varies from industry to industry. For some businesses, it is purely about branding and embellishment. Others have to do so to comply with the regulatory requirements. For instance, a leather goods manufacturer may wish to engrave its logo on one of the faces of its products. This is entirely an activity revolving around the brand and how it aims to market itself. An airbag manufacturer, on the other hand, needs to take its marking requirements much more seriously because of the consequences. Not only does the regulation bind them, but for the sake of the safety of their users, they need quick and reliable identification when a batch of their product malfunctions.
For high-volume manufacturers, executing their marking requirements manually will never allow them to meet the demand. Furthermore, automation allows for operational efficiencies. The same applies to the marking industry. Reducing human intervention is not always necessarily about reducing costs. Machines allow for improvement in production efficiency. From the industrial revolution the world saw during the era of railroads to Henry Ford’s mass vehicle manufacturing line, it is important to realize that we stand today at the cusp of another such event. Automated laser marking solutions provide engravings as fine as a few tenths of a millimeter. Automated impact based equipment provides deeper engraving marks and of a better resolution than was previously possible.
However, there are instances when manual is the only method to move forward.
Large objects that require marking can often need marking solutions that are portable. This allows for in-situ marking. But designing an automatic system does not constitute a feasible solution in most cases, an example in the illustration above. Hence, the marking devices try to minimize a user’s workload, but human intervention is important to execute the task.
Humans are building manufacturing lines and have product development processes today with automation built in. From conveyor belts to robotic arms, the manufacturing industry is looking for new avenues to optimize operations.
Production lines of today have designs that are versatile and adaptable. What this means is that the designers understand that building new infrastructure to add new technologies to a setup every time around will result in high cost and inefficiency. Similarly, marking equipment manufacturers also understand how manufacturing plants are built and design their products for easy installation in a production setup. A combination of both these aspects gives the perfect recipe for automating marking.
The design of marking automation can be divided into two sections. One is the production line. The second is the marking equipment. The production line end shall need to ensure that the component is in proper position and remains there while marking is done. Once the part is in position, it shall inform the marking equipment which in turn shall begin marking. Once marking is complete, the marking machine tells the production line to allow the marked piece to move forward and position a new work-piece. This is a high-level design that is repetitively taking place.
A design with more detail will take many factors in consideration. Foremost will be the electronics that shall carry the signals between the production line and the marking equipment. Similarly, the mechanical design for holding and positioning parts to accurately mark will need working on. Equally important are safety features. To prevent any high intensity laser reflection off a surface or human entering between a work piece and a dot-peen machine, planners may enclose the entire marking work area.
Marking Equipment Design
To embed their tools in an automatic production setup, marking equipment manufacturers have taken intensive steps. Marking machines now come with programmable software. Users can modify parameters such as speed, strength of marking, material types, marking patterns, etc. Furthermore, the electronic design ensures that signal protocols commonly in use in industries are available for easy integration of marking tools. User interfaces are extremely simple requiring no major training for operators and an overall plug-and-play methodology is in action.
Automatic Marking: Technologies at Work
Automatic marking methods use various technologies to accomplish the task. Let us start with the simplest of methods, that is inkjet printing. The term simplest is used in the loosest of ways. Some machines that are used in highly technical operations are quite complex in design. But automatic printing is most easily understood due to the widespread usage of printers.
There are various ways in which inkjet printing is implemented. One method is Continuous Ink Jet printing. A print-head nozzle expels ink droplets that are electrically charged. Due to the high speed of the ejection of droplets, direct contact with the surface requiring marking is not a requirement.
The Citronix series of continuous inkjet (CIJ) printers are simple, reliable, and able to print permanent lot codes, date codes, logos, barcodes, and text to any type of substrate including metal, glass, wood, plastic, paper, and more.
DOD or drop on demand
Another method is DOD or drop on demand inkjet printing. A print head with a set number of holes allows for drops to flow through them ‘on-demand’. These holes are in a single column pattern and operate independently. As the surface moves across the face of the print-head, the dots leave marks on the face. In a continuous process, this results in the graphic or marking that the user feeds the system. Below is DOD print-head:
TIJ or thermal inkjet
A third method is TIJ or thermal inkjet marking. It uses a cartridge which has an ink reservoir and an array of resistive elements. The resistive element, when activated by an electrical current, heats the ink in contact with it. This results in ink droplet formation and which then ejects out of the faceplate nozzle onto the substrate in a precisely controlled manner.- TIJ technology typically has a lower hardware cost and a smaller production line footprint.
Linx TJ725, in the picture above, ensures a more reliable and easy to use coding solution than any other thermal inkjet (TIJ) printer on the market.
Another option that involves printing, is using automatic labeling machines. Attachment of pre-printed labels using this equipment is in use in multiple product manufacturing lines. From direct marking on products to sticking labels to entire cartons, they make for a quick marking solution. Label making machines allow for quick printing of the labels. They can be inkjet printers or laser label printing machines, in combination with an attachment mechanism to the product of interest. These are the core parts of an automatic labeling machine.
LASER is short for “light amplification by stimulated emission of radiation”. Electromagnetic waves are excited to a level that they emit energy in the form of light. Using optical amplification, these light-emitting waves transform into a high energy light beam. With the right amount of power, these lasers can permanently affect the surface they come in contact with. Laser marking machines use this principle to mark a surface. Flying Laser Marking Machine is mainly in use for continuous manufacturing processes where any standstills of the manufacturing plants will be uneconomical.
Let us look at some of the major technologies for laser label printing machines driving automation today:-
Fiber Laser Machines
Fiber lasers achieve their optical amplification by passing through a fiber optic cable. These cables are quite similar to the ones in use for data transmission. A lens at the end of the fiber assembly straightens and directs the laser onto the surface of interest. The required marking pattern etches or burns along the surface as either the laser head or the bed moves in directions that a computer program tells it to.
Heat Sign is another manufacturer of automatic marking solutions but has a wider range of products. This is so because they provide solutions in inkjet, dot peen, and laser technologies.
This is the HS FL-50 fiber laser marking machine by HeatSign. This 50W machine is mainly used for deep metal laser engraving or a large area content marking. Some customers need their machine to reach the working range 300mm x 300mm on hard structures like steel. HS FL-50’s design allows it to meet such requirements.
UV Laser Machines
As evident from its name, UV lasers use a light source of the ultra-violet range in the light spectrum. The UV laser removes the surface material and in this process, no heat is generated. Instead, the energy gets used in removing the material and hence the method is known as ‘cold processing’. UV laser marking machines are much more diverse than fiber machines when it comes to the type of materials that a user can mark. What they offer in diversity, they lack in intensity. UV lasers are weaker and do not provide deeper marking. However, they are easily controllable and allow for highly accurate markings.
CO2 Laser Machines
A CO2 laser, when built, comprises a mixture of gasses which include helium and nitrogen. However, since the CO2 gas emits light, the entire laser is known by its initials.CO2 laser marking can cater to a wide range of non-metallic materials such as plastics, textiles, glass, acrylic, wood, and stone. These machines easily integrate into the food packaging and pharmaceutical industrial setups. They are also automating the marking process of PVC pipes, building materials, mobile phones, electrical appliances, integrated circuits, and electronic components.
HS-CL20 CO2 Laser Coding and Marking System use high-quality RF CO2 Laser Tube made of tough metal. It also has a Galvanometer System for digital scanning from the core of the system.
Dot Peen or Dot Pin
Pin stamping machines use carbide pins that strike and indent a series of dots onto the surface of a material. They are mounted on a rapidly actuating arm. Fully automatic dot peen marking machines will have software controlling the overall design marking process. It will move the actuating arm assembly on the surface in x and y directions. As the pin traces the surface, it creates a succession of dots that form the required graphics. These graphics can be digits, text, logos, and 2D Data Matrix codes. This method is quick and precise. Furthermore, the markings do not cause the material any major stresses. –
Pryor is a UK based brand that also manufactures marking solutions across different technologies.
With a team of mechanical, electrical and software engineers in-house, Pryor specializes in developing automated marking solutions. Robotic control is integrated directly into Pryor software so that robot moves can be programmed as steps in the marking process.
Automation is critical for businesses to be competitive today. The marking industry is playing its part to ensure the world of manufacturing does not face any limitations in this aspect. A wide array of solutions that employ different technologies are now available to automate the marking process.