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Specific Maintenance Procedures and Requirements
Published in Ryan Cruzan, Manager’s Guide to Preventive Building Maintenance, 2020
Most manufacturers’ door closers are adjusted with two or three screws located on the body of the door closer. The screw marked ‘B’ adjusts the speed of the backswing or door opening speed. The screw marked “S” adjusts the swing speed of the door as it is closing. If an “L” screw is available, this adjusts the latch speed which is the last few inches of the door’s swing just before the door latches.
Potential for harvesting electrical energy from swing and revolving door use
Published in Cogent Engineering, 2018
J.S. Partridge, R.W.G. Bucknall
A simple swing door was modelled to act as the reference to which a generation system could be added. The door closer was considered to consist of a torsional spring, which was compressed as the door opens, with the energy then released to close the door. A viscous damper controls the velocity of the door during closing until the door reaches the latching angle. At this point the viscous damper stops acting on the door to allow the door to close properly. As such it was considered that there were four phases to be considered for a door opening event.The door is initially closed and at rest, with an opening force applied until the door angle reaches 60° open. This was modelled as a forced-mass-spring system, with a constant force applied.The door is then brought to rest as a result of the kinetic energy of the door being converted to potential energy in the spring. Modelled as a mass-spring system with initial conditions determined from the conditions at the end of phase 1.The door closes due to the energy stored in the spring acting on the door. The speed is regulated by a viscous damper, which offers critical damping. This is modelled as a mass-spring-damper system, with the initial conditions set by the end conditions from phase 2.Once the opening angle of the door reaches the latching angle, 7° (0.12 rad), the viscous damper no longer acts on the door, with the spring acting to fully close the door. A mass-spring system with initial conditions determined from the end of phase 3.