What Is a Gas Spring?
A gas spring, also known as a gas damper, gas pressure spring, or gas pressure damper, is a device that utilizes compressed nitrogen gas and oil within a sealed cylinder to exert a force in a specific direction—typically to push the piston rod out of the cylinder.
Due to their low spring constant, gas springs offer smooth operation with minimal force change over large strokes, making them maintenance-free. However, their reaction force may vary with temperature changes and could decrease over time due to the pressure of the enclosed gas.
Uses of Gas Springs
Gas springs find extensive use in automotive hatchbacks for opening and closing mechanisms. They are also employed in various applications such as doors of shelves and windows, supporting and holding the weight of the door in the open position. Their design often facilitates both opening and assisted closing. Beyond automotive use, gas springs are utilized in industrial equipment and office automation equipment.
Structure of Gas Springs
Gas springs are categorized based on their installation orientation: those that can be mounted in any direction and those with a limited installation angle, usually with a ±60° tolerance and the piston rod positioned lower. Despite the structural differences, the operational principle remains consistent across all types.
Principle of Gas Springs
Gas springs function by providing a nearly constant force over long strokes, facilitated by the differential pressure acting on the piston within the sealed cylinder. This pressure difference is achieved through the design of the piston and the specific arrangement of nitrogen gas and oil within the cylinder, allowing for smooth extension and retraction of the rod under controlled conditions.
Types of Gas Springs
Diverse gas spring types are tailored for specific functions and requirements:
1. Standard Type
These are designed for lifting or pushing down heavy objects, commonly found in equipment covers and car hoods.
2. Push-Open Type
Similar to the standard type but incorporates a mechanism allowing the spring to extend automatically when lightly pushed, useful in applications like retractable outlet taps.
3. Type With Lock
Locking gas springs are divided into rigid and elastic types, with the former locking securely at any position and the latter providing cushioning to absorb impacts, suitable for adjustable tables and office chairs respectively.