Industrial robots are increasingly assisting human labor in tedious and repetitive tasks. Most often, their implementation in production lines is determined by factors such as increasing productivity, reducing costs or improving quality. However, there are types of operations where automation plans may be influenced not only by economic issues, but also by safety considerations and attention to cleanliness. Let’s take a look at the industrial robots YAMAHA offers for specific types of applications..
In manufacturing and service environments where, by the nature of the business, the presence of significant amounts of dust, dirt or condensed water in the air is unavoidable, it is impossible to safely use conventional types of industrial robots. Unwanted particles, getting under their housing, will almost certainly cause the failure of a precision device.
However, the use of industrial robots in conventional configurations is also sometimes excluded in environments with a high degree of cleanliness. This time, on the opposite principle – it is the particles escaping from under the housing of the device that come from, for example, adhesives, seals or consumables that can contaminate the room and destroy the results of the work carried out there. The basic prerequisite for the use of machines in clean rooms is to equip them with the appropriate IP (International Protection Rating), while the parameter that most often defines the scope of protection of equipment is then considered in the opposite direction than usual, informing about the degree of tightness of the equipment itself.
In order to solve the above problems, special series of industrial robots have been developed for use in the so-called harsh conditions and in cleanrooms. Generally speaking, these are devices whose mechanisms and, in particular, housings have been additionally sealed – so as to protect their interior or working environment from the penetration of harmful agents. In the case of designs intended for clean zones, it is also used to generate a vacuum inside the robot to reduce the risk of emitting particles in case the connections of moving parts are not fully sealed. In addition to being highly airtight, the housings are also designed so that there are no kinks or nooks where dust particles could collect. Their surfaces are additionally painted with special paints that do not emit any particles into the environment. Alternatively, they are made of materials such as stainless steel or polished aluminum to allow easy cleaning with chemicals used in clean rooms.
In what follows, we will take a look at YAMAHA’s range of industrial robots, in terms of available harsh environment and cleanroom series.
Working in harsh conditions
YAMAHA supplies SCARA-type robots for use in dusty environments or where water is dispersed. The YK-XGP series uses seals and design that allow the robots to function indoors corresponding to an IP 65 rating – which means protection against solids at level 6 (dust resistance), and against water intrusion at level 5 (resistance to water from any direction at pressures up to 30 kPa, at up to 12.5 l/min, for up to 3 min).
The series is based on the beltless technology characteristic of most YAMAHA robots. This design was achieved by using direct coupling of the ZR axis. This drastically reduces lossy motion, maintaining high accuracy and eliminating the risk of machine failure or loss of precision due to belt stretching or deterioration over time. This reduces the frequency of servicing the device, which is of considerable importance for many types of production – including those carried out in harsh conditions. The YAMAHA SCARA YK-XGP series of robots includes as many as twelve models with different specifications: with arm lengths from 250 to 1000 mm and maximum payloads from 5 to 18 kg.
Work in cleanrooms
YAMAHA also supplies SCARA-type robots and single-axis robots designed for cleanroom use. Depending on the level of cleanliness required, two series are available: the YK-XC, which maintains ISO Class 4, and the YK-XGC, which maintains a very high ISO Class 3. Cleanrooms are isolated spaces in which, through the use of appropriate filtration and ventilation systems and procedures for the use of these areas, specific parameters of air cleanliness are maintained. Air purity is commonly expressed on a nine-grade scale derived from ISO 14644-1, which defines the size and maximum allowable number of particles-pollutants per cubic meter of air. This is a descending scale, where ISO grade 9 remains the least restrictive standard and ISO grade 1 the most restrictive and, consequently, the most difficult to achieve. In practice, Class 8 and Class 7 cleanrooms are the most commonly used.
The robots of the two aforementioned series have been designed to reduce the escape of particulate matter from their interiors and surfaces. Here, mechanical components have been fully encapsulated with covers made of reduced-dust plastics, and moving parts have been carefully sealed. The Z-axis has been protected by a bellows cover. A vacuum is generated inside the robot to prevent the escape of particles that could be produced by mating moving parts and degrading wear parts, seals or lubricants. The YK-XGC and YK-XC series includes as many as twelve models with different specifications: with arm lengths from 180 to 1000 mm and maximum load capacities of up to 20 kg. With the exception of two models, all of these robots use the beltless design discussed earlier. An additional advantage of this technology is that it eliminates the risk of particulates from a wearing belt entering the atmosphere.
In addition to the SCARA series of robots, YAMAHA’s cleanroom offerings include a wide range of single-axis and Cartesian robots. An excellent example is the FLIP-XC series of single-axis devices, with stroke lengths from 50 to 2050 mm. Thanks to the vacuum generated and the protection of the stainless steel sliding surface, they are able to operate even in rooms maintaining ISO Class 3 cleanliness. Their maximum lifting capacity is 120 kg, making them suitable as a base for other robots – such as the SCARA type, extending their reach.
Where are the so-called cleanroom robots used?
Increasing levels of automation have been rapidly encroaching on more and more manufacturing areas. It is therefore natural that there is also a growing demand for production automation that takes place in cleanrooms. All integrated circuits used in , i.e., consumer electronics are cut from delicate silicon wafers, a process that undoubtedly needs to be carried out under conditions of increased cleanliness. The growing popularity of smartphones, smartwatches and so-called wearables is raising all the time the requirements for the quantity of components produced. At the same time, as a result of the prevailing pandemic and other factors, more and more medical devices are being developed, the production and assembly of which also require such standards. Huge volumes of tests, increased research into vaccines and new diagnostic methods are all the time raising demands on robot manufacturers to deliver ever faster, more precise and cheaper machines ready to work in rooms with the highest standards of cleanliness
What are the requirements for robots for use in clean areas?
The basic prerequisite for the use of machines in cleanrooms is an adequate degree of IP protection – the well-known parameter of equipment protection is considered in the opposite direction in this case. In simple terms, the idea is that nothing should escape from the inside of the equipment. Robots are full of wires, gears, and therefore lubricants, belts and many other elements that, during operation, emit particulates/dust, lubricant droplets and vapors into the atmosphere, from which cleanrooms must remain free. One of the hallmarks is also the provision of vacuum to the robot housings so as to increase confidence that the machine will not emit anything from its interior in the event of not fully sealed connections of moving parts. The robot housings are designed so that there are no nooks and crannies where dust can collect. Surfaces are painted with special paints that do not emit any particles into the atmosphere, or made of stainless steel/polished aluminum so that they can be easily cleaned with chemicals used in cleanrooms.
Summary
Thanks to advances in technology, heavy-duty manufacturing automation, until recently difficult to achieve, is now becoming a viable prospect for many businesses. Developed to work in environments with high levels of dust, condensed water or high-cleanliness, modern robots provide a cost-effective solution that is capable of supporting human hands in activities that threaten health or require high precision.
The distributor of YAMAHA ROBOTICS equipment is the RENEX Group. The available range, as well as other products from the RENEX catalog, can be seen and checked in operation in test conditions of production lines (also on the company’s own components and subassemblies) at the RENEX TECHNOLOGY AND TRAINING CENTER. RENEX Group also provides comprehensive consulting and advisory services in the field of production process automation and production of cleanroom equipment and maintenance. The center also provides training in programming and operation of both SMT equipment and industrial robots.
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