Container weighing with two bending support points and one load cell

For scales with less stringent demands on precision (e.g. fill level weighing applications), only one load cell and two bending support points can be used for a three-point bearing instead of three load cells.

With a four-point bearing, two load cells and two bending support points can be used for fill level weighing.

The layout with bending support points is a particularly economical solution in which horizontal forces can be absorbed at the bearing level. This means that additional fixing is not necessary. If large horizontal forces occur outside the bearing plane (e.g. wind forces), additional precautions must be taken.

Under the following conditions, a set of scales that is equipped with bending support points can achieve an accuracy of between 1 % and 2 %:

• The container must be of symmetrical design
• Equal load distribution must be ensured even with a full container
• No variations in the center of gravity are permitted (e.g. caused by heaped objects)
• The distance between the load cell and bending support point must be as great as possible
• The bending support points must be mounted so that a tilting line results. For example, two bending support points must lie with their arms on a common line or the surfaces of their arms must lie on a common surface.

If there is are differences in temperature between the container and the foundation, the resulting differences in distance between the support points must be compensated by one fixed bearing and one moveable bearing. The fixed bearing and the moveable bearing have the same dimensions. The fixed bearing is bolted to both the foundation and the load carrier. The moveable bearing is only secured to the foundation or only to the load carrier. The contact surface which is not secured serves as a sliding surface. The direction of sliding is determined by two side guides that are mounted on the load carrier or foundation.