Tool holder with built-in cavities

A tool holder for chucking a tool shaft by frictional engagement, comprising:

• a main body for coupling the tool holder to a spindle of a machine tool;
• a clamping surface joined to the main body, or a tube part joined to the main body, for fixation of a tool shaft by frictional engagement;
• and
• at least one portion of the clamping surface or tube part is shaped in one piece by primary shaping, in which an outer connecting channel extends into an interior of the portion and there, on a side of the clamping surface or tube part facing away from a mouth of the tool holder, widens, forming a plurality of interconnected cavities with a first cavity connected directly to the outer connecting channel and connected to at least one second cavity positioned in a direction toward an opening of the mouth of the tool holder, wherein the first cavity and each of the at least one second cavities are connected to one another via a connecting channel having a smaller inside cross-section than an inside cross-section of the first cavity and each of the at least one second cavities, and wherein the plurality of cavities are located entirely in the interior of the portion shaped in one piece by primary shaping,
• wherein the plurality of cavities are tight on their own even at extremely high internal pressures since the plurality of cavities are embodied entirely inside the one-piece portion, wherein the clamping surface or the tube part is composed of individual metal layers that are successively applied to each other until the damping surface or the tube part has a predetermined shape, and
• wherein the plurality of cavities are filled with a fluid, and a pressure producer, actuated from outside, is built into the at least one outer connecting channel, and the fluid can be subjected to pressure by the producer, and wherein the fluid flows through the outer connecting channel into the first cavity without flowing in a countercurrent direction relative to the fluid flow through the first cavity.