Dampers
Dampers or “shocks” are devices that can restrict motion through viscous friction, usually paired with an external spring or moving masses such as doors and panels. Dampers generate an opposing force to motion which is directly proportional to velocity.
Dampers are specified by their stroke (distance traveled) and their constant of proportionality (c) between the forces generated the velocity travelled, expressed as Force/ velocity (N/m/s or Lbs/in/s). For example, to control the closing time of a door of mass “M” at the damper pivot point, using a damper stroke “S” at time “T”, a damper with c = M/S/T should be specified.
Figure 3- Schematic of a linear damper
The constant of proportionality for a damper is controlled by its size (defining the fluid flow rate through the piston), the piston orifice size and oil viscosity, both defining the resistance levels to oil flow. For example, a damper with a small orifice will provide more resistance to oil flow through the piston, dissipating or absorbing kinetic energy of the system attached to it. Similarly, using more viscous (thicker) oil will have the same result.
IGS dampers utilize valved pistons that enable different damping settings for extension and compression strokes.
For customers unfamiliar with the use of dampers, our technical sales team can provide support in specifying the appropriate damper as well as optimum mounting points to address their needs.
Damped Gas Springs
Damped Gas Springs are compact devices integrating a gas spring and a damper in one unit, commonly used in moving masses at a specific velocity such as gates and door panels. As with dampers, the mass “M”, stroke “S” and time, ”T” are required to specify a damped gas spring. However, unlike dampers which generate a resisting force, damped gas springs output a controlled drive force capable of displacing the mass at the required velocity.
IGS damped gas springs are mainly categorized as fully damped and partially damped gas springs:
Fully damped gas springs can be described as damper units filled with nitrogen gas at high pressure (Figure 4). These units provide an even control through their stroke and can be used at any orientation.
Figure 4- Schematic of a fully damped gas spring
Figure 5- Schematic of a partially damped gas spring
Partially damped gas springs can be described as compression gas springs filled with high volumes of oil. These springs create a two-stage damping effect as the piston is passing through the gas (considerably less viscous than oil) and oil regions.
These units must be used only at the rod-down orientation.
IGS damped gas springs can be tailored to our customers’ specific applications. Please contact our technical sales team for assistance.