This is an attempt to create the image that Lazur URH was referencing to, however I have no idea if this comes close. Not a curve definition, just an image.
螺旋線圈
black、gray scale、GrayScale、GreyScale、grey scale、Lazur URH、line art、lines、monochrome、request 203115、request completed、requestfilled、spiral
黑色、灰度、灰階、灰階、灰度、Lazur URH、線條藝術、線、單色、要求203115、請求已完成、requestfilled、螺旋
資料來源：openclipart ( https://openclipart.org/ )