Physical principle behind constant force spring
When you walk into your office building on your way to work every day, or into your local bank, or any commercial facility, you may open a heavy glass door. When you cross the threshold, the door closes behind you, and you don't think about it. However, the heavy glass door was probably closed by a constant force spring. Constant force springs are widely used in daily applications. From door closers to rope and hose retractors, to sports equipment, toys, motors, etc., constant force springs exert force at an amazing high frequency and consistency. Let's take a closer look at the basic physics behind the constant force spring. In the 17th century, the British physicist Robert Hooke proposed a formula for force and elasticity, which is now called Hooke's law. Hooke's law states that the force (f) required to stretch or compress a spring for a distance (x) varies linearly in proportion to that distance. The formula is f=kx, where k is a...