The patented, Positive Force Gate Closing System (PFGCS) is the creation of locksmith David Mowery. For years customers wanted a closer that would keep pool area gates closed and latched without slamming or having to be replaced after a few years. The problem is most pool gates and fencing is five feet tall or less and standard door closers would be in the way of access or egress as this limited height has no overhead clearance. For most pool gates, the only closing options are coil style springs or spring hinges.
Coil springs and spring hinges are designed to become longer under a load. When coil springs are in the unloaded condition, the coils are normally touching. These springs have two significant problems when it comes to closing a gate. The first problem is how much force is exerted to stretch a spring is about the same amount of force exerted by the spring to retract. The greatest amount of energy is at the maximum point of expansion, not at the end of the retraction, which is where a door requires the greatest force in order to operate the lock mechanism’s latch.
In addition, gate springs and hinge springs are not available with controllable retraction. Roughly put, the bigger the spring, the shorter the expansion and the faster the retraction. The speed and force of retraction are increased or decreased simultaneously, not separately.
Over time and under the influence of stress, springs slowly deform (technical term creep). They permanently begin losing their storable mechanical energy. The loss is at the end of the retraction.
This will result in the gate not have sufficient force to close and latch, leaving an unlatched gate. In today’s world, a non-closing pool gate is a significant liability to a homeowner, private and public facilities and homeowner associations.
To solve the pool area gate problem, David developed a way to incorporate a door closer as the closing mechanism. When properly operating, a door closer does not slam the door shut. Instead, the closing force is adjusted to safely close and latch the door at the prescribed speeds.
For form and function, the Positive Force Gate Closing System is based on an overhead concealed door closer whose arm can travel in both directions. Locksmiths have installed these hydraulic closers for over 40 years.
The concealed overhead closer style was chosen because of its compact size and capability of double acting. Unlike a surface-mount door closer, the concealed closer is designed to operate in both directions for center-hung door applications. Surface mounted door closers are handed, operating in one direction only.
With this capability, the Positive Force Gate Closing System can be installed in left or right hand single acting door applications and also double acting applications. Instead of using hinges to secure the gate to the fence, this system incorporates a bottom center hung pivot to ensure smooth opening and closing operation with minimal force.
The Positive Force Gate Closing System is designed for gates that are no more than four feet wide and weigh less than 200 pounds. The closers are spring and speed adjustable to make certain that the different size and weight gates properly close and latch.
There are three Positive Force Gate Closing System Kits. The kit that will be installed for the purpose of this article is the bolt-on kit designed for square tube gates and fencing. The bolt-on kit contains all of the components necessary to install the unit onto a two-inch square fence post and one-inch square gate channel.
The kit includes the closer with K-arm, closer housing, end cap, center hung bottom pivot assembly, modified K-arm housing and Tek screws. The closer housing is mounted onto the hinge post and the modified K-arm housing is mounted onto the top channel (horizontal) adjacent to the hinge post. Unlike standard door applications, the closer body is mounted with the spindle and the short end of the body over the gate.
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