I am trying to come up with a formula to tell me how and how much to preload a spring for a new product. The data that I'm starting with is as follows:
Imagine a spring in a the shape of an uppercase j, minus the flat on top, and instead of an arc on the bottom it has two right angle bends and a horizontal in between. The short leg is what holds the spring in position, and I'm assuming (not what actually happens but I think it will make things easier) that the spring only bends through the lower right bend under load.
Data I have is reaction load and horizontal deflection at two locations. Imagine the j spring as it is written, then position 1 is halfway up the length of the long side and the horizontal deflection is to the right. Position 2 is at the top of the j (end of long leg), and deflection again goes to the right. I've posted results of the raw data in the attached image.
I need to come up with a formula that makes load a function of angular deflection and moment arm (length from bottom to loading position), or a function of linear deflection and moment arm. I've tried beam caculations, but E is not constant but rather behaves inverse proportion to deflection. Once I have an idea of how to relate the things I need to, I can find out how much to over underbend the wireform to give me the required preload once it's installed. The new spring is also pretty simple, with a short leg, and a bend followed by a long leg.
Thanks
Imagine a spring in a the shape of an uppercase j, minus the flat on top, and instead of an arc on the bottom it has two right angle bends and a horizontal in between. The short leg is what holds the spring in position, and I'm assuming (not what actually happens but I think it will make things easier) that the spring only bends through the lower right bend under load.
Data I have is reaction load and horizontal deflection at two locations. Imagine the j spring as it is written, then position 1 is halfway up the length of the long side and the horizontal deflection is to the right. Position 2 is at the top of the j (end of long leg), and deflection again goes to the right. I've posted results of the raw data in the attached image.
I need to come up with a formula that makes load a function of angular deflection and moment arm (length from bottom to loading position), or a function of linear deflection and moment arm. I've tried beam caculations, but E is not constant but rather behaves inverse proportion to deflection. Once I have an idea of how to relate the things I need to, I can find out how much to over underbend the wireform to give me the required preload once it's installed. The new spring is also pretty simple, with a short leg, and a bend followed by a long leg.
Thanks
