Patent ID: 7978815

Claim:
Compact density measuring instrument for measuring density of fluids in a volume in a container, especially in a fluid flow in a pipe, the instrument comprising a radiation source in the gamma range positioned on one side of the fluid and a detector positioned on the opposite side of the fluid for receiving said radiation, and the fluid being contained in the container, wherein the source is positioned in a source housing, said source housing being at least partially fitted into a corresponding recess in the container wall, said source housing comprises a source holder containing the gamma source positioned in the holder axis and comprising a coaxial opening from the source through one end of the holder, said one end adapted to be aimed toward the fluid, wherein the outer part of said one end of the source holder has an essentially conical shape with decreasing radius toward the fluid and being adapted to fitted into a corresponding cavity in the container wall and wherein the recess and cavity together have a depth less than the thickness of the container wall, thus leaving a part of the container wall between the tip of the cone and the fluid.