Swing gates can be operated by a range of different motors that include:
Ram gate motors
Articulated arm openers
Rams have a compact motor body containing a slender piston arm. One end of the body of the motor is mounted to the fixed gate post, wall or brick pier that the gate is hung on. The other end of the protruding piston is attached to the gate.
The piston is extended out of the motor housing to open the gate and retracted back into the housing to close it. Hydraulic fluid under pressure pushes the piston out of the motor housing and reducing the pressure pulls it back in.
Linear screws look similar to ram gate motors, but they don’t use a moving piston to open and close the gates. Instead, a threaded shaft runs inside the motor casing and is turned by an electric motor. The gate mounting point is internally threaded and screwed onto the threaded shaft. As the motor turns the threaded shaft, the gate mounting point is screwed up and down the shaft to open or close the gate.
Articulated arm motors open and close automatic gates using a jointed metal arm attached to the motor output shaft. The motor housing is mounted to the gate post or wall that the gate is hung on and the end of the arm is attached to the gate. When the motor turns, the articulated arm opens or closes the gate.
Underground gate motors
Underground motors are discrete gate operators that are hidden in pits dug directly below the gate hinges. A short arm is slotted onto the gate motor output shaft at one end and the other is bolted or welded to the bottom of the gate. As the motor turns, the gate opens or closes.
These are incredibly discrete motors, but they need specially made posts to house them. As the motors are installed inside the gate post, nothing is really visible.
The Pros and Cons Of Different Swing Gate Motors
Ram gate motors are strong, and they use the principle of leverage to their advantage. The gate mounting point is a long way from the hinge, so they don’t require a lot of force to open and close gates. During installation, care needs to be taken to ensure that the geometry is correct so that the piston can move freely.
Articulated arms can be installed on thicker pillars further from the plane of the gate. They are also more tolerant of slight installation inaccuracies. Like rams, the attachment to the gate is away from the gate hinge, so they need less force to open and close gates.
Underground gate motors require careful installation as the motor output shaft has to be in line with the top hinge of the gate. Undergrounds also need good drainage because their electric motors cannot be sat in water for any period of time. Finally, underground gate motors need to be strong to apply the higher force required to move the gates from so close to the hinge.
In-post gate motors have the same issues as undergrounds but don’t need drainage. They are mounted above ground inside specially built gate pillars or posts.
Can Automatic Swing Gates Open Outward?
Automated swing gates can open either away from the property or towards the property. Sometimes, this is determined by the available space or other factors at the installation site. So, what governs which way automatic gates move?
Swing Gates That Open Outward
Gates that open away from the house could open onto pavements or even into the road. For obvious safety reasons, this unacceptable. One way round this is to have the gates mounted far enough up a longer drive. In this way, they can open fully within the property boundary. Normally, swing gates open towards the property to avoid any of these issues.
If outward opening gates are being considered, it’s usually because of one of the following reasons:
Swing Gates And Sloping Driveways
The open end of a swing gate draws the arc of a circle as it moves. On a flat drive, the bottom of the gate is the same height from the ground throughout this arc. However, if the ground rises where a driveway has an upwards slope on it, the gate will scrape on the ground as it opens.
One way round this involves the use of special gate hinges that open the gates at an angle. Another solution is to hang the gates on higher hinges, but this leaves a larger gap under the closed gates.
Yet another way of solving this problem is to have the gates open outward as discussed above.
Ultimately, if there’s no room for gates to swing open outward, sliding gates offer an alternative that avoids the problem completely.
Swing Gates And Obstacles
For safety, it’s highly recommended that automatic gates have safety features built into each system. Without safety devices like photocells, safety edges and motors with obstacle detection, swing gates will collide with anything in their path as they move.
Even with safety features built in, moving swing gates will stop if there’s an obstacle in their way. Consequently, the area swing gates move through as they open and close must be clear of parked cars, walls, the house, plants etc to ensure that the gates can work properly.
Bi-Fold Swing Gates
Bi-fold swing gates are effectively normal swing gates cut in half vertically with the two sections hinged together to make a folding gate. When they’re open, they’re completely folded so they take up just a little bit more than half the space of traditional swing gates. When closed, they are unfolded so they cover the full width of the driveway.
On paper, this looks like the perfect way to deal with space limitations but there are a few things to consider.
Bi-fold driveway gates always used to run on a track in the ground or a rail above the gates. This keeps the opening or closing edge of the gates in place. A lot of people don’t like the idea of overhead rails and they obviously prevent taller vehicles from entering. Tracks across the driveway need to be kept clear of leaves and gravel to ensure the gates’ smooth passage.
There are two pairs of hinges used on each leaf of bi-fold gates and they must be installed carefully so that they can move through their full range without binding.
For anyone who wants bi-fold gates but doesn’t want either a track or overhead rail, there is now a kit that does away with both. As before, only careful installation of the gates, hinges and the kit will ensure smooth operation and a close stop is needed for the gates to close onto.
All bi-fold gates can be automated by standard swing gate automation motors but there’s a limit to the size of bi-fold gates for residential properties.
Automatic Swing Gates And Wind
If it can get quite windy where you live, swing gates may not be appropriate. Fully boarded gates have no gaps in them, so they act like a yacht’s sail when wind blows on them. They have to push against the wind blowing against the direction of their movement.
But swing gates are not always moving against the wind. They start at right angles to where they end up. It’s quite possible for a swing gate to start moving with no wind blowing directly onto it and finish with the full force of the wind on it. This can be confusing for the gate controls, and motors with obstacle detection can think that the gate has hit something when the full force of the wind pushes on it. In extreme cases, sliding gates are suggested as the best alternative.