Ekstensjonsfjær

An ekstensjonsfjær, also known as a tension spring or pull spring, is a mechanical device designed to resist tensile force. It is typically made of coiled wire, such as steel, and is characterized by its ability to extend when a pulling force is applied to its ends. The spring stores mechanical energy when stretched and returns to its original shape when the force is removed, a property known as elasticity.

The construction of an ekstensjonsfjær usually involves winding a wire around a mandrel to create a helical coil. The ends of the spring are often formed into loops, hooks, or eyes, which serve as attachment points for connecting to other components. The pitch, or spacing, between the coils can vary, with closely wound springs typically having no initial gap, while those with a gap will exert a small force even in their unextended state.

Ekstensjonsfjær find widespread application across various industries and everyday objects. They are used in garage doors to counterbalance their weight, in trampolines to provide rebound, in vehicle suspension systems, in door closers, and in numerous small mechanical devices like pens and clasps. The specific design and material of an ekstensjonsfjær are chosen based on the required force, extension range, operating environment, and lifespan. Factors such as wire diameter, coil diameter, number of coils, and material properties all influence the spring's performance characteristics.