How to choose a five-axis machine tool?

Among the many parameters of themachine tool, one data attracts particular attention, and that is the number of axes. Especially when some new machine tool products are released, companies will always emphasize the number of axes to highlight the good performance of the machine tool. Recently, the editor also discovered in communicating with some netizens that many people like to "judge the quality based on the axis", especially some non-industry netizens who always feel that multi-axis is really powerful. So is it really true that the more axes a machine tool has, the better? What parameters should you look at when selecting a five-axis machine tool?

About the number of machine axes

The machine tool axes mentioned here refer to the degrees of freedom of the machine tool. Several axes represent several degrees of freedom. For example, the usual three-axis refers to the plane movement of the workbench plus the up-and-down movement of the tool, and the four-axis refers to the previous three axes plus the rotation of the workpiece or the rotation of the workbench, etc. Theoretically, the greater the number of axes, the higher the freedom of machine tool processing and the stronger the functionality of the machine tool. However, this does not mean that more axes is better. The reasons are as follows.

1. In addition to looking at the number of axes, we also need to look at the linkage

Whenever we talk about multi-axis machine tools, there is also a multi-axis linkage. As mentioned earlier, the axis of the machine tool refers to the degree of freedom of the machine tool processing, and the linkage of the machine tool means that the servo axes (excluding the spindle) can interpolate at the same time. For example, five-axis five-linkage means that five motion axes can move simultaneously and coordinately when processing the workpiece. If one or two of the five axes cannot move at the same time as the other axes, then the machine tool is called "five-axis four-linkage" or "five-axis three-linkage". Theoretically, the number of axes can reach more than a dozen axes, dozens of axes or even hundreds of axes, but the linkage may not necessarily reach such a high level. This is why five-axis and five-linkage machine tools are regarded as important national equipment resources. Therefore, whenever a multi-axis machine tool comes out, some netizens always want to emphasize linkage, because linkage can better demonstrate the performance of the machine tool in a three-dimensional way.

2. In addition to the degree of freedom, accuracy and rigidity are also important.

Machine tools refer to machines that manufacture machines. They have many types and a wide range and play an important role in the modernization of the national economy. For different processing, the requirements for machine tool type and performance are also different. Therefore, although multi-axis can bring a higher degree of processing freedom and functionality, in many cases, the workpiece to be processed is not that complicated, but it affects the accuracy and performance of the machine tool. Rigidity requirements are higher. At present, multi-axis machine tools have obvious advantages in processing complex workpieces and efficiency, but they do not have an absolute advantage in accuracy. On the contrary, the rigidity of the machine tools is slightly weaker due to the complex body design. In short, the best one is suitable for processing. Faced with different workpieces to be processed, the more machine tool axes are not the better.

About the selection of five-axis linkage machine tools

Although not all processing requires the use of five-axis linkage machine tools, five-axis linkage machine tools do represent the high-end level of machine tools and are an effective means to solve complex processing of impellers, blades, marine propellers, heavy-duty generator rotors, etc. With the development of the manufacturing industry, the processing requirements for machine tools are getting higher and higher, and the consumer market for five-axis machine tools is also expanding. So what parameters can you refer to when selecting a five-axis machine tool? The editor will briefly introduce it below.

Restricted by the diversity of parts to be processed and factors such as machine tool speed, accuracy, and stiffness, the five-axis linkage machining machine tool is still a special-purpose machine tool. Therefore, the design and selection of five-axis machine tools must first start with the parts being processed and typical machining trajectories, that is, considering the relative motion trajectory characteristics of the tool and the part, the tool movement accuracy/speed/space, and the classification and accuracy inspection of the motion axes of the five-axis machine tools. wait.

In addition, in the design and selection of high-speed five-axis machine tools, the following basic principles must be observed. 1. Do the motion characteristics of the machine tool structure conform to the motion trajectory characteristics of the tool relative to the surface of the part? 2. Does the "composite motion accuracy" of the machine tool meet the requirements for tool motion trajectory accuracy and motion speed? 3. Does the size of the machine tool meet the space required for the tool motion trajectory? If there are no problems with the above, it can basically be determined that the selected five-axis machine tool meets the processing needs.