Norton 7500 Series
Door Closers
• Non-handed
• Rack-and-pinion design
• Cast aluminum body
• 2-1/8" projection
• 1-1/2" diameter piston
• 5/8" diameter pinion journals
• Standard, separate and independent, latch, sweep and backcheck intensity valves
• Backcheck positioning valve
• Molded plastic cover
• All standard arm applications allow doors to swing 180 degrees, conditions permitting
Closer bodies are constructed of a special aluminum alloy, carefully selected to accommodate interactive steel components and operating conditions.
Rack & pinion operation provides a smooth constant control of the door through its full opening and closing cycle. 180° door swing can be achieved when door, frame, hardware and arm function do not interfere.
Adjustable Delayed Action Closing (Optional)
An optional hydraulic feature, available in lieu of backcheck, adds a third speed range to the closing cycle. This feature becomes effective when the door is opened and released at any point beyond 70°. The amount of time delay depends upon the combination of the angle of door release and valve adjustment. The valve can be adjusted with a 1/8" (3mm) hex key from no delay time up to maximum delay times of:
Door Opened
and Released at
|
Approximate Time
of Delay Cycle
|
180°
|
4-5 minutes
|
120°
|
2-3 minutes
|
90°
|
25-30 seconds
|
|
