There is a growing use of smaller cobots on assembly lines as they are ideal for:
- automating repetitive operations and making the best use of the operators’ skills
- carrying out most tightening jobs automatically
- being quickly reprogrammed and used for different applications, which makes them the perfect choice even for low-volume runs or for variable workflows with quick operational setup changes.
With their specific features, they also offer:
- flexibility for process automation (they can be programmed to work in reduced mode when a human comes within range of the robot and resume full speed as soon as the person leaves)
- great ease of programming and very fast setup
- increased production capacity, quality of tightening processes and hence of the resulting end products.
However, operator safety aspects when using these devices are very important issues for a well-informed choice because little is said about the safety aspects and underlying regulations because it is a fairly recent production innovation.
Now let us look at what the regulations say:
The regulations state that: “… in the use of collaborative applications, there are two main types of risk to be analysed: contact and access to the work space. The objective to be reached – again according to the regulations – is a minimal transfer of energy from the robotic system to the human, and the systems for minimizing this type of risk consist in reducing speed and force, reducing the moving masses (i.e. the weight of the robot), adopting a rounded or smooth design, and the use of force/torque control systems.”
Analysing the cobots used for automatic tightening, we can see that they are all provided with sensors to detect contact with objects/people.
In Fiam’s case, the automatic tightening device clamped to the cobot’s wrist has a forward bit stroke.
What does forward bit stroke mean?
It is a patented device designed to allow the blade to advance to the screw automatically and, because it requires hardly any thrust for tightening, means this system is perfectly in line with safety requirements.
Moreover, this device fully complies with the regulatory requirements because:
- it is extremely light and very small in size
- the screw is always held inside the screw holding doors and the screw is only shot out once the screwdriver head is positioned by the cobot over the tightening point: this means that the tip of the screw is never exposed during handling and hence cannot hit the operator.
If you also want to implement this type of technology and would like to learn more about how to improve the performance of your production processes, fill in the form at this link: http://bit.ly/2FRBv3x
