Over the last few months many individuals may have found themselves doing more yardwork than normal. With this shift into lawn care, people have rekindled an interest in maintaining and improving their property, and having tools that are durable, efficient, and reasonably priced is extremely important. The decision on which actuator to install in lawn care machinery is vital to provide the most optimal experience for consumer satisfaction and goes a long way in appraising the company’s image. Now, whether you should select an electric over hydraulic linear actuator is something we will discuss in detail below.
Hydraulic Actuator: How It Works
The first question to be addressed is: “What is a hydraulic actuator?” In short, the hydraulic actuator working principle is the compression of fluid in a hydraulic cylinder and forcing that pressure in a controlled direction. When the hydraulic pressure is forced in this direction, a motion is applied to a ram usually, driving whatever the ram is attached to. Hydraulic actuators have a large operating range, usually from 1,000 to 4,000 pounds per square inch (PSI), but higher PSI ranges are obtainable depending on the application. They require a throttle component such as a valve or slide to manage the hydraulic fluid in one direction or the other (extending or retracting the ram). General applications of this actuator in the industry consist of heavy-duty machinery, damper doors, clamping, and presses.
Pros of Hydraulic Actuators
When it comes to hydraulic actuators, there are numerous factors that provide certain benefits that other actuators do not possess. Firstly, they provide the highest force to weight ratio, due to the compression of high viscosity and high-density oil. Additionally, it is much safer to use hydraulic actuators in comparison to others, given the fact that they are generally simple in design and have gone through decades of design innovations. Furthermore, they have impressive resistance to vibrations and the ability to absorb heavy loads. Overall, hydraulic actuators are excellent for heavy-duty applications and are reliable, with a long-life cycle.
Cons of Hydraulic Actuators
Where there are advantages, there are also disadvantages with hydraulics, however. They can be quite costly given their initial installation costs, usually, the owners do not reap the return for an extended period of time. Consistent maintenance is necessary, and there are numerous factors that need to be considered and upheld constantly: the seals need to be in good shape so the fluid cannot leak, the throttle device must be cared for, hydraulic fluid will need replacing when a leak occurs, and broken attachment components can be common due to the force load they apply onto them. On the occasion of a leak, not only does it damage the machinery itself, but it may even lead to environmental contamination as oil is not exactly known to be eco-friendly. It certainly is not healthy for your garden. Another issue is that they are comparatively less responsive and have a certain lag compared to their counterparts. This may lead to issues pertaining to effective usage given that lawn work is generally not heavy-duty and would require an expensive high-speed hydraulic actuator.
What is an Electric Actuator?
Electric actuators maintain a simple build and add quite a few advantages. The actuator is energized with an electrical power source feeding a motor. The motor begins turning, converting the original electrical energy source into physical torque. The motor turns a lead screw and gearing that drives the actuator in one direction or another. Modern technological innovations have paved the way for electric actuators with higher mechanical efficiency, speed operation, and the ability to bear more load, making it quite the competitor of hydraulic and pneumatic actuators. In fact, there is a hot debate on hydraulic motor vs. electric motor among product designers. It is most commonly used in various applications such as robotics, agricultural machinery, valve operations, and other such operations.
Pros of Electric Actuators
Due to the design and power source, electric actuators are fast, precise, and clean. Hydraulic fluid can have a lag in its control when initially starting or changing direction, whereas the electric energy source utilized in an electric actuator can alter directions almost instantly. Precision driving capabilities with the electric actuator are available due to a tight control tolerance with extraordinarily little backlash or slack in the conceptual design, compared to the gate-way control of a hydraulic valve. Additionally, they are less prone to temperature variations. They are also highly cost-effective unlike their hydraulic brethren, which have higher running costs and require expensive auxiliary equipment. There is little to no chance of environmental contamination due to the lack of usage of fluids. Furthermore, an aspect that is slightly overlooked by most people is the safety that these actuators provide, as the screw jacks and actuators are generally self-locking and have minimal backlash, resulting in unprecedented precision. The level of maintenance required is not as demanding as well, nor does it require constant handling, unlike an electric hydraulic actuator. Finally, electric actuators can take advantage of electronics in general. A prime example of this is the inclusion of limit switches, which restrict the ram’s motion beyond its extreme points.
Cons of Electric Actuators
Even though electric actuators seem to be a perfect choice, there are obviously some downsides that one must consider. One of the immediate cons is the force or horsepower they can generate, which does not match up with that of hydraulic actuators. Also, the structural design is much more complex as compared to the simple hydraulic system which means that in case of failure, repair costs will generally be higher due to difficulty in opening the system. However, Progressive Automations can make heavy-duty linear actuators capable of force over 3000lbs in varying stroke lengths, and with proper maintenance, it is possible to live out the life cycle without having to commit to any sort of repair. We also offer an 18-month warranty and have engineers on-hand to assist with any queries you may have, including in instances of failure.
Various Lawn Care Equipment and Electric Actuators
Depending on the size of the yard an individual can have various pieces of equipment to help preserve and develop their landscape. Some of this equipment could be items like a lawn spreader, lawn tractor, and riding mowers. A lawn spreader is used to spread seed, fertilizer, manure, and other items across the lawn. An actuator for a lawn spreader controls the gate which determines the flow of the aforementioned items. If someone wanted precise control to firstly, not waste any seed, or secondly, go from a completely closed to an open gate to spread fertilizer, an accurately driven electric actuator would be the correct tool for this process. Lawnmowers have a cutting deck that is raised or lowered to initiate cutting of grass. Having the deck lowered too far can kill the grass by burning it or gouging the ground and destroying the landscape. Having it raised up too high would result in an inefficient cutting job and require a second attempt at mowing. The lawnmower actuator allows for a precise, controlled deck level to be maintained continuously so that the appropriate cutting height is achieved.
Lawn tractors are used in cutting grass also, but they could also have attachments such as a lifting bucket for dirt, gravel, soil, or other items. Linear actuators drive this bucket in various directions to allow for lifting, lowering, and tilting to properly maneuver the items inside. Again, the correct electric linear actuator can have more than enough power to drive this bucket and handle with any reasonable amount of load. This is concurrent to also maintaining a lower energy consumption, minimal maintenance, and utilizing a clean energy source without the risk of having to clean up leaking hydraulic fluid. Tractors should also look to utilize electric actuators for any window control if necessary, mirror adjustment due to the confined space, and console adjustment for ease of access. Lawn tractors and mowers can also utilize electric steering actuators for lawn tractors for steering their wheels on uneven terrain.
Electric or Hydraulic: A Summary
With respect to the applications of each actuator in lawn care equipment, the following table provides a precise overview on what to consider when installing actuators in this type of machinery.
Lower Cost & Maintenance
High initial investment and maintenance cost
Precise and Fast
Lag due to Fluid Compression
No Chance of leakage and Contamination
Risk of leakage of hydraulic fluid
Less prone to temperature variations
Temperature may affect performance
Complex Structure and Design
Simple and Reliable Design
Low Torque/Force output
Heavy-duty Force output
In the case of lawn care equipment, the usage of electric actuators seems to be the natural inclination. They may not offer high output force in comparison to hydraulic actuators, but for the purpose of trimming some grass in the back lawn, it is more than sufficient. What it does offer is much more than any hydraulic system could ever provide. It is precise in its motion control and offers high-speed ratios, meaning there will be a minimal delay between the user’s command and the machinery’s response. They are better at handling the occasional tugs and impacts the lawn turf subjects to cutting equipment. The lack of fluid in its internal components and resilience to temperature variations guarantees that your customers do not have to worry about maintenance or performance issues while gardening.
Overall, it is best to choose electric over hydraulic cylinders for most lawn care machinery and equipment and should be your go-to for most of your future endeavors.
Progressive Automations can find a solution for whatever the problem is. If you are eager to learn more about these actuators and what they can do for you, please feel free to contact us.