Symmetrical three-axis parallel spindle head capable of multi-directional fixed-point rotation

A symmetrical three-axis parallel spindle head capable of multi-directional fixed-point rotation, the spindle head comprising:

• three branch chains, each of the branch chains having the same structure and being spaced axisymmetrically about an axis with 120° spacing between adjacent ones of the branch chains;
• a moving base connected with a corresponding one end of each of the three branch chains;
• and
• a fixed base connected with a respective main body of each of the three branch chains;
• wherein a machining spindle is fixedly connected to the moving base;
• wherein each of the branch chains comprises:
• a respective servo motor,
• a respective branch chain rod,
• a respective lead screw, and
• a respective guide nut, and
• wherein for each of the branch chains:
• a respective one of the lead screws and a respective linear guide rail are provided in a respective inner cavity of a respective first end of the corresponding branch chain rod;
• a respective first end of the corresponding lead screw is connected with the corresponding servo motor;
• the corresponding lead screw passes through the corresponding guide nut;
• a respective second end of the corresponding lead screw is connected with the corresponding branch chain rod via a respective rotating pair;
• the corresponding servo motor and the corresponding lead screw provide a degree of freedom of movement between the corresponding branch chain rod and the corresponding guide nut;
• the corresponding guide nut is mounted on the corresponding linear guide rail and is rotatably connected with the fixed base via a first support disc,
• a corresponding second end of the corresponding branch chain rod is rotationally connected with the moving base via a second support disc;
• wherein each of the branch chains is connected to the fixed base via a respective fixed base bearing such that each of the first support discs is connected with a respective inner ring of the corresponding fixed base bearing, and such that a respective outer ring of the corresponding fixed base bearing is fixedly connected with the fixed base;
• wherein each of the branch chains is connected to the moving base via a respective moving base bearing such that each of the second support discs is connected with a respective inner ring of the corresponding moving base bearing, and such that a respective outer ring of the corresponding moving base bearing is fixedly connected with the moving base;
• wherein a respective rotation axis of each of the fixed base bearings intersects at a respective one intersection point in space with a respective rotation axis of each of the moving base bearings, such that there is one respective such intersection point for each of the three branch chains, and wherein the three intersection points of the three branch chains determine a plane.