The characteristics and selection of five-axis simultaneous machining centers.

Whether it's a five-face machine tool or a five-axis simultaneous machine tool, they are all derived by adding at least two rotary axes to the three linear motion axes (X, Y, Z) on the basis of the three rotary axes (A, B, C), thereby resulting in various layout schemes for five-axis machine tools. The appropriate machine tool structure layout is determined based on the shape, size, weight, required precision, mechanical properties of the material, and cutting load of the workpiece.

Based on the layouts of three-axis vertical and horizontal machining centers, ten common layout modes and their applications are obtained by configuring different rotary motion patterns. In the table, there are two types of rotary axes: the separated type, where the tool and the workpiece each have one rotary axis, and the integrated type, where both rotary axes are assigned to the tool or the workpiece, commonly referred to as a double rotary axis. This can be in the form of a swiveling milling head or a double swiveling rotary table.

There are two types of double rotary tables: A/C and B/C. Although they work on the same principle, the A/C table has greater rigidity. However, when the table is oriented backwards, due to the limited space, the swivel angle of the B/C table is generally smaller to prevent interference. On the other hand, the B/C table with a single-arm support typically has less rigidity but a larger swivel angle range, which is convenient for observation and suitable for processing small parts.

Obviously, the structure of the rotary axes plays a crucial role in the function and performance of five-axis machine tools. In recent years, the development of its structure has mainly included the following four aspects:

(1) Adopting torque motor drive to reduce mechanical transmission and improve dynamic performance, such as the Cymill milling head from Saite Company.

(2) Three-axis swiveling milling heads, which offer excellent performance. The angle changes more flexibly and quickly, such as the M3A/B/C three-axis swiveling milling head from Zimmermann Company in Germany.

(3) The development of compact A/B double-swiveling milling heads, such as the DTH A/B double-swiveling milling head from Rambaud1 Company in Italy. The swivel angle has been increased to 45 degrees. Additionally, the parallel rod mechanism milling head developed by China's Qier Machine Tool Company for horizontal axis A/B swiveling angles is novel, but the swivel range is small.

(4) The vertical cross-axis structure is converted from a 45-degree inclined plane rotation, commonly referred to as the B-axis. Due to the larger rotating joint surface, it can improve rigidity and braking torque. However, when the inclined plane rotates 180 degrees, the swivel angle of the axis is only 90 degrees, so the swivel range is small, making it more suitable for five-face machining applications.