Spring axis

The helical curve used for sweeping the circle profile is centered about the spring axis. The axis is defined by two 3D points: the start point and the end point. 3D points can be defined by 3D nodes, as well as by any 3D object suitable for defining a point in the space. The vector defining the spring axis will be directed from the first point to the second one (those also defines the start and the end of the spring, respectively). The shape of the curve is defined by the spring parameters. The swept profile will be normal to the original curve.

Spring main parameters

The shape of the body resulting from this operation is defined by the following parameters:

•The radius of the spring wire – defines the radius of the circular profile, whose sweeping forms the body.

•Spring radii/diameters at the ends – the radii/diameters of the helical curve at the start and end of the spring (mean start and end radii are equal in the case of a cylindrical spring). You can select which Mode to use: Mean radius, mean diameter, inner diameter, outer diameter.

•Spring coiling direction: Clockwise (right) or counterclockwise (left).

•The step (pitch), the number of coils and the free length of the spring.
The spring can be defined using any two of the three parameters: Pitch, Coils, Length. When two parameters are already enabled, one of them will be automatically disabled upon enabling a third one. By default, the free length of the spring is defined as the distance between the 3D points defining its axis. In this way, it is sufficient to define just the pitch or just the number of coils – the other parameter will be calculated by the system automatically. In cases when both the pitch and the number of the spring coils are defined, the spring length will be defined solely by those parameters.

   

Initial position of spring profile

Initial position of the spring profile is set arbitrarily by the system. It can be modified by defining the desired position with the help of an additional 3D point – profile starting location (profile start point) – or by specifying the numerical value of the start angle (profile rotation angle) in relation to the original position.

Once the start point of the profile is specified, it will snap to the plane passing through the selected point and the spring axis.

   

When both the start point and the numerical value of the rotation angle are specified, the latter is measured from the profile position defined by the start point.

 

Compression and grinding of spring ends

If necessary, the end coils of the spring can be compressed (closed/squared) and ground. The diagram below shows a spring with one coil compressed at the start, and one coil compressed and ground by 3/4 wire diameter at the end.

Spring position with respect to start and end points

If the spring length is defined by the pitch and the number of coils, you can force the spring alignment by the start or the end point.

Aligning by start point

Aligning by end point