Andy Jackson began Builders Brass Works in the early 1950’s making high end, high quality door pulls, dome stops, kick plates, hinges, flush bolts and various other types of door hardware for the construction industry. He knew that quality would be a key ingredient of his success. To ensure this...
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Cross holes at the forward end of the closer case connect to one or more valves that adjust the amount of flow into a port hole, which ends at the reservoir. Over the years these closers have evolved. Originally, one valve controlled both sweep and latch. Now there are two – one controlling each function – and. depending upon the configuration of the closer, a third valve that controls a hydraulic back check.
The length of movement of the springs’ compression, determines the swing of the door. Jackson overhead concealed closers are available with a swing of 90 degrees, 105 degrees or 120 degrees opening. The size of the fixed springs determines the opening force and affects the maximum flow of hydraulic fluid. The fixed spring sizes are Extra Light Duty (XLD), Light Duty (LD), Regular Duty (RD), and Heavy Duty (HD).
Jackson 20-330 Series Overhead Concealed Closers are manufactured under ISO 9001 guidelines. The 20-330 is non-handed, single- or double-acting, and can accommodate center hung or offset applications. There are three different types of overhead concealed closers. Jackson uses color coding to identify them: brown, blue and black. All three of the closers are the same shape and size.
The standard (brown) overhead concealed closers come in four different fixed spring sizes and are available having a 90-degree or 105-degree opening. These standard closers are available with hold open or non hold open.
The adjustable spring power (blue) overhead concealed closers come with springs that can be adjusted from 4.5 lb to about 15 lbs. Jackson springs are both compressed at the same rate making the unit more consistent and increasing durability. Adjustability is particularly important when trying to accommodate the balance between stack pressure within a building and Americans with Disabilities Act (ADA) codes. Closers leave the factory set at size Light Duty for a 7’0” by 3’0” door. To change force one size takes approximately four turns. To decrease pressure, turn counterclockwise. To increase pressure, turn clockwise. This closer is also available as a 90-degree or 105-degree hold open or non hold open.
Jackson has introduced a unique variation of the overhead Concealed adjustable closer called the “Easy OpenTM,” essentially an adjustable overhead concealed closer equipped with an 110VAC motorized mechanism that changes the spring pressure. The “Easy Open” is normally operated by pressing a momentary switch.
At rest, the “Easy Open” is normally set to between 8 and 10 pounds opening force. Pressing the momentary switch activates the “Easy Open.” The motor adjust the closer opening force down to approximately five pounds, making opening the door ADA compliant and meeting state codes that require minimum opening force. Once the door has been opened for a pre-set time, the motor begins to readjust the closer to the approximate eight- to ten-pound opening force. This does not affect the closing operation of the reduced force opening. However, once the door has been closed, the door will return to the preset opening force helping to offset any stack pressure within the building.
The Grade One (black) overhead concealed closers have been tested to ANSI Grade 1 standards (2 million cycles). These Grade One closers are available with hydraulic backcheck. They are available as 90-degree, 105 degree or 120 degree opening and with hold open or non hold open.
The overhead concealed door closer also acts as the top pivot for the operation of the door. The door is connected to the closer with an arm that is either offset or center hung. Center hung doors are mounted to the closer spindle using either an End-Load Arm or a Side-Load Arm. The way the door is attached is determined by the cut-out at the top of the door - end load arms are installed on the butt edge of the door and side load arms on the side or face of the door.
There are three different styles offset arms for single acting doors. One arm has no pre-load. A second arm has 1-1/2 degree pre-load, and the third arm has 2-1/2 degree pre-load. “Preload” means the closer (arm) continues to place pressure against the door even when the door is closed helping it to stay shut.
Unlike the gear-driven piston type closer, Norton says its cam action closer is significantly more efficient, providing up to four pounds closing force for a five pound opening force.