|
About Us |
Gallery |
Contact Us |
Links |
Home |
Spiral Spring |
|
 | The photo at the left is of a hood hinge that is used on pickup trucks. This hinge uses a spiral spring as a counter-balance. Below is a close-up of this spring.  |
| When spiral springs are loaded, the coils are forced to one side in a non-concentric position (see the Before picture below). Then as the hinge is opened or closed, the coils rub against each other and create an objectionable noise which is amplified by the hood. In the past, grease was applied to the spring to reduce the noise, but this adds cost, makes painting difficult, and the grease would eventually be washed away or be squeezed out of the coils and the noise would grow louder. Engineers at Third Coast Engineering developed a mounting design which counter-acts the coil bind and holds the spring in a concentric position (see the close-up photo above and the After picture below). |
|
 |  |
| The new mounting design was quite simple and inexpensive to implement. The round pin normally used to capture the end of the spring was replaced with a split pin, similar to the one used at the center of the spring. This split pin imposes a torque to the end of the spring and keeps the coils in the concentric position. |
|
| This design proved very successful in reducing the noise and also increased the effective stiffness of the spring, allowing the manufacture to use a smaller spring and reduce the part cost. This mounting design is now used on numerous applications including hood and trunk hinges and door windows. |
|
| This mounting design was awarded a patent. If you are interested in looking at this patent, please click on the patent number below. You will need Acrobat Reader© from Adobe to view this file. Click the Acrobat logo below to get it. |
|
US05294097 |
|
 |
|
Contact Us |
|