As the name suggests this actuator creates motion on a straight line. It doesn’t take the shape or the route of the conventional circular motion as is the case with many circular motors.
Many technological gadgets and tools that use electricity tend to need actuators of whatever shape. Although the circular motion is prevalent, recent electrical equipment tends to require other forms of actuators thus the need for linear actuators.
It is now possible to see many heavy types of machinery such as those in industries use linear actuators. Other areas where there is an increasing need for linear actuators are gadgets like printers, disk drives, dampers, valves, computer peripherals among other things.
You can expect to find many machines using linear actuators, which in the end produce the required power. Pneumatic and hydraulic cylinders evidently produce linear motion. Because many of these machines in the market are either hydraulic or pneumatic, there is a need to understand how linear actuators work.
As it were, an actuator needs a few important things to remain operational. First, it needs a strong and reliable source of energy. Coming in number, two is a control signal. Without the two fundamental things, the actuator whether linear or circular will not work.
The beauty is that the control signal doesn’t require a lot of energy. In fact, it requires low energy. Therefore, you shouldn’t really worry about power consumption. The source of power is also not a big issue here, as long as it is electrical or hydraulic (pressure-created), there is no worry. By the way, even human power can sustain the actuator.
Designers of the linear actuator ensure that once the control signal receives the power from any of the three sources, the actuator responds promptly. The result is to convert the signal’s energy into something else, mechanical motion.
Now that you have information on what a linear actuator is, a control signal, the sources of power the actuator needs and how the control signal uses the power to create mechanical motion, let’s delve into how this tool works.
How a Linear Actuator Works
If you are new to actuators, it may be a bit hard when we talk about them here. However, the aim here is that we want to make it very simple for you. In the end, you will perfectly understand not only how actuators work but also precisely, how a linear actuator works.
First, it is important to note that many people use different terminologies when they refer to actuators. In fact, some go as far as using terms such as electric pistons, activators, and others still call them rams. Whatever the case, they usually refer to linear actuators.
Therefore, no matter the name you use, chances are you are referring to the same thing, linear actuators. It is also important to know that actuators do according to their name, they actuate. This means they move up and down or on a straight motion to create energy.
To start with, it is worth knowing that actuators come in different strokes. To get the stroke you desire, you need to adjust or look for the right size of the screw and shaft that you need. It can be longer or shorter.
The other thing you need to put in mind is that strokes come in different forces and speeds. You can achieve the right force or speed by simply changing the gears that are between the screw and the Direct Current (DC) motor.
Essentially, if the screw turns faster, you are going to achieve a low force. This is possible because when it comes to force and speed, the two interchange. When one is on the higher side the other is definitely, low.
If you see that you do not need the shaft to stop, there is something you need to do. Actuators come with inbuilt switches. Many people refer to them as micro or limit switches.
The nut that is inside the microswitch triggers the switch. Remember that the limit switches are inside the shaft, which is at the center of the main actuator. When the nut slides the screw up and down, the microswitch stops moving.
Actually, a linear actuator has two shafts. One of them is at the top extended position while the other is on the lower re3tracted position.
As the actuator hits its limit, the nut that is inside the shaft triggers the limit switch. The result is that power to the DC input is cut thus the actuator stops working.
- If you reverse the power polarity, the actuator can move to the opposite direction. Whichever the case, the actuator will only work if there is power. If there isn’t a source of power, the linear actuator cannot work.
The Right Actuator
After learning a lot about what a linear actuator is, how much power it uses, the kind of power that can run a linear actuator, and how it works, it is important to ask yourself another question. With many actuators in the market and a lot of people realizing their use, it is easy to confuse. Most people, especially those that are new to actuators find themselves in a difficult situation when choosing the right actuator. To that end, it is important to ask, which is the right actuator for me?
However, before you get to answer that question, it is imperative to contemplate about the following questions:
- What are you going to use the actuator for?
- What amount of force do you need?
- How much travel or stroke do you really need?
- Do you need it to be slow, medium or faster?
- How regularly do you intend the actuator to do all these?
Unless you determine the exact answers to the above questions, getting the right type of actuator will be a daunting challenge. Many people may need an actuator that works at a faster pace but the one that will be in use once in a fortnight. This will not be ideal.
