Most people who rarely encounter linear drives in life call them different things like "pusher" or "electric piston", which are quite unwary terms.
A linear actuator is a mechanism that performs a function directly related to its name, namely, it performs the linear movement. That is, the actuator moves the rod, carriage, or turntable.
But when it comes to choosing the right device, you should get the gist of the technology and understand how the types and features of actuators differ. Let’s figure this out in more detail.
Linear actuators are great to use as they are:
- simple in mechanism construction;
- fit for continuous, non-stop use;
- sturdy and waterproof;
- reinforced in external protection (certain models).
It is not surprising that the popularity of these devices keeps them in demand. After all, their range of application constantly increases with more and more specialized areas.
The essential requirements for actuators are travel speed, force, and stroke. Of course, there are other characteristics that are also important when choosing a linear drive, but they often depend on the operating conditions one has in mind.
This can include a temperature range, maximum speed, frequency of use, supply voltage, and others. To get a fitting, high-quality device, it is also necessary to pay attention to a working cycle property.
What is an Actuator Working Cycle?
The actuator working cycle is a fraction of the time during which the drive can perform work without stopping. Quite often you can hear the term “actuator load factor”, this is the same indicator of the ratio of continuous operation of the drive.
If it is indicated that the working cycle is 10%, then the actuator operates continuously for one minute out of ten, regardless of what kind of reciprocating movement it performs.
A working cycle of 100% is almost never reached, as this can lead to the device’s rapid wear and mechanical problems. An example of a full-on working cycle is a bicycle. The mechanism requires constant, continuous work for the implementation of the movement. But when it comes to robotics and automation processes, a 100% working cycle remains a rare case.
hat is the peculiarity of the working cycle and why is this aspect so important? In fact, the quality of the entire mechanism depends on it. The non-stop operation of the actuator can pose a serious risk to the device. Thus, the drive can undermine the manufacture by violating the limits of the operation.
There is a universal working cycle calculation formula:
Working cycle (%) = (drive turn-on time) / (turn-on time + turn-off time)
For instance, if the actuator performs movement for 15 seconds and then rests for 45 seconds in 1 minute, then the working cycle will be:
Working cycle = (15) / (15 + 45) = 15/60 = 0.25 = 25%, respectively
This is how the working cycle of any linear drive is calculated. Now, when searching for the necessary mechanism, pay attention to this indicator. Surely, your choice will depend on the purpose of use (industrial equipment, domestic use, robotics), and certain requirements. But the indicator of the working cycle remains the most important characteristic when selecting an actuator which you expect to serve long and true.
You can find cases when the manufacturer indicates a 100% working cycle on a product more often in the market nowadays. Most often this happens with devices for domestic, home use, when there is no need for extensive movements. As for agricultural machinery, medical equipment, and the like, actuators with a working cycle of about 10-20% are more common.
Selecting a Noiseless Linear Actuator
Another fundamental characteristic when selecting an actuator is noiselessness. We are used to the fact that it is always noisy at large manufactures because a lot of equipment works at the same time. But in today's realities, people have become more worried about health, and engineers are puzzling over the optimization of daily environmental impacts.
That’s why silent linear drives are no novelty and pretty commonplace. Especially, considering the fact that actuators have taken root not only in industrial equipment - we often use them in everyday life.
How to define the level of noise?
The decibel table is used for this. As you may know, decibels measure the intensity of sound. This value was named after the famous inventor Alexander Graham Bell, who invented the phone among other things. And although we often hear the term “decibel” (dB), most people are poorly versed in what it is and where it can be used.
Man is gifted with a truly stunning hearing. We perfectly hear the light crack of firewood in the fireplace, the bursting thunder during a thunderstorm, and can enjoy live music at a concert. But we don’t always distinguish between noise levels.
Therefore, when choosing the right actuator, it is worth considering the future location and the corresponding level of sound produced in it. After all, if you install a mechanism with a noise level of 100 dB in the living room or bedroom, no peace and tranquility can be expected once it is turned on.
Figuring Out Noise Indicators
A decibel system is used to determine the noise level. The indicators start from zero, which means maximum noiselessness, then the indicator is multiplied by five or ten. This forms a stepped table.
Common noise level definition table:
That is, if you see a mark <45 (A) when selecting a linear actuator, this means that the sound of the mechanism will be a little quieter than a regular talking person yet a little louder than a whisper.
It is also important to keep in mind that the “A” mark may refer to the measurement of sound level in one kilohertz. That is, if you notice that the selected actuator operates at one kilohertz, then the noise level will correspond to an indicator of 45 dB. Simple arithmetic.
Silent Linear Actuators
In fact, electric linear actuators are very quiet mechanisms. Perhaps, one of the quietest, because there is no longer a need for air canisters and the noise of compressed air during movement, has long been a thing of the past.
But today, the topic of noise has become more relevant than ever. More and more manufacturers, even representatives of large industrial enterprises, are trying to reduce the production-related stress by lowering noise.
What to say about household needs. Everyone appreciates peace and quiet in everyday life, so the low noise level when using home appliances is especially appreciated by the consumer.
Progressive Automations offers a wide range of motion control equipment. Perfect for both home and commercial use. Most of our items have a noise level of 45 dB or even less, which means most of our products won’t spoil your comfortable home environment or interfere with the active working environment in the office.
If you are interested in high-quality automation, we have a whole line of products with excellent characteristics, an appropriate working cycle, and a low noise level.
And if you find it difficult to select the right device, feel free to contact us for help. We will help you make a choice or develop an individual design. The Progressive Automations team is always ready for new challenges to provide the customer with a quality product.