@elvinfitzmaurice
Profil
Registered: pred 1 year, 8 months
Linear Actuators: what they're and the way to decide on them
A linear actuator is a self-supporting structural system capable of reworking a circular motion generated by a motor into a linear motion along an axis. Serving to to produce movements such because the pushing, pulling, raising, decreasing or inclination of a load.
The commonest use of actuators includes combining them with multi-axis Cartesian robot systems or utilizing them as integral parts of machines.
The principle sectors:
industrial automation
servos and pick-and-place systems in production processes
assembly
packaging and palletisation
Certainly, just think of applications equivalent to airplane, laser or plasma reducing machines, the loading and unloading of machined items, feeding machining centres in a production line, or moving an industrial anthropomorphic robot alongside an additional exterior axis as a way to increase its range of action.
All of those applications use one or more linear actuators. In line with the type of application and the efficiency that it must guarantee in terms of precision, load capacity and velocity, there are numerous types of actuators to choose from, and it is typically the type of motion transmission that makes the difference.
There are three foremost types of motion transmission:
belt
rack and pinion
screw
How can you ensure that you select the suitable actuator? What variables does an industrial designer tackling a new application have to take into consideration?
As is often the case when talking about linear motion solutions, the necessary thing is to consider the issue from the fitting viewpoint – namely the application and, above all, the results and efficiency you are expecting. As such, it is price starting by considering the dynamics, stroke size and precision required.
Let’s look at these in detail.
High Dynamics
In many areas of business design, corresponding to packaging, for instance, the demands made of the designer very often should do with speed and reducing cycle times.
It's no surprise, then, that high dynamics are commonly the starting level when defining a solution.
Belt drives are often the perfect solution when it comes to high dynamics, considering that:
they permit for accelerations of as much as 50 m/s2 and speeds of as much as 5 m/s on strokes of so long as 10-12m
an X-Y-Z portal with belt-pushed axes is typically capable of handling loads starting from extremely small to approximately 200kg
in accordance with the type of lubrication, these systems can supply particularly long upkeep intervals, thus ensuring continuity of production.
Wherever high dynamics are required on strokes longer than 10-12m, actuators with rack and pinion drives tend to be a superb solution, as they allow for accelerations of up to 10 m/s2 and speeds of up to 3.5 m/s on doubtlessly infinite strokes.
The choice of a special type of actuator wouldn't guarantee the identical results: a screw system, which is undoubtedly much more precise, would definitely be too sluggish and would not be able to handle such long strokes.
Lengthy Strokes
Systems created by assembling actuators within the typical X-Y-Z configurations of Cartesian robotics often, in applications similar to pick-and-place and feeding machining centres alongside production lines, have very lengthy strokes, which may even reach dozens of metres in length.
Plus, in many cases, these lengthy strokes – which normally contain the Y axis – are tasked with dealing with considerably heavy loads, usually hundreds of kilos, as well as quite a few vertical Z axes which operate independently.
In these types of applications, your best option for the Y axis is certainly an actuator with a rack and pinion drive, considering that:
thanks to the rigidity of the rack and pinion system, they're capable of operating along probably unlimited strokes, all whilst maintaining their rigidity, precision and efficiency
actuators with induction-hardened metal racks with inclined teeth which slide along recirculating ball bearing rails or prismatic rails with bearings are capable of handling loads of over 1000kg
the option of putting in a number of carriages, each with its own motor, permits for numerous impartial vertical Z axes.
A belt system is right for strokes of up to 10-12m, whilst ball screw actuators are limited – within the case of lengthy strokes – by their critical speed.
Positioning Repeatability
If, on the other hand, the designer is seeking maximum precision – like in applications such because the meeting of microcomponents or certain types of dealing with within the medical field, for instance – then there is only one clear selection: linear axes with ball screw drives.
Screw-pushed linear actuators provide the very best performance from this viewpoint, with a degree of positioning repeatability as high as ±5 μ. This efficiency cannot be matched by either belt-driven or screw-driven actuators, which both attain a most degree of positioning repeatability of ±0.05 mm.
Website: https://www.firgelliauto.com/collections/linear-actuators
Diskusné Fóra
Počet vytvorených tém: 0
Počet reakcií: 0
Rola: Účastník (Participant)