Development of the most popular CNC machine tool f

Development of high-speed deep hole machining CNC machine tool

(3) select new deep hole drilling tools, and process them in place at one time in the machining center, but its equipment investment is too large. The equipment investment of the above methods is too large, and the later operation cost is high. High speed special type or adding support in the pipe wall is difficult, but it is very effective. Deep hole drilling machine can not only effectively improve production efficiency, but also reduce equipment investment

1. Overview of the machine tool

1.1 main components and layout of the machine tool

the machine tool adopts horizontal double-sided double station layout, with a hydraulic shift slide in the middle, and a fixture is placed on the shift slide. The left and right sides of the slide base are respectively connected with a non-standard side base, and a numerical control feed slide and a hydraulic feed slide are placed on each side base. The non-standard drilling head is placed on the slide table. The spindle of the drilling head is a machining center spindle with internal cooling holes (with rotary joints and cutting cylinders), and is equipped with a drilling head transmission device. The conveying device is connected to the fixture body and moves with the fixture. The machine tool automatically conveys the workpiece, hydraulically clamps it, and uses the automatic lubrication system to lubricate the guide rail. The spindle of the machine tool is equipped with internal cooling. The coolant is discharged into the cooling box from the slide base, and the magnetic chip removal device in the cooling box discharges the iron chips. The machine tool is equipped with an outer package. The structural drawing and sectional view of the machine tool are shown in Figure 1 and Figure 2 respectively

1.2 machine tool action cycle

the workpiece is manually pushed onto the slide of the conveyor along the outer raceway of the machine tool, and the conveyor automatically transports it to the fixture along the slide, which is clamped with wedges and locked with hydraulic pins. The left and right hydraulic slides are fast forward and work in. After the processing is completed, the left and right hydraulic slides are fast forward and work in. The shift slides are moved to the second station. The left and right CNC Feed slides are fast forward and work in. After the work in reaches a certain position, one slide returns to its original position, and one slide continues to drill through. After the processing is completed, the slide returns to its original position, the clamping cylinder is loosened, the pin is pulled out, and the conveying device sends the workpiece out of the fixture and onto the docking support plate, The shift slide moves from the second station (feeding position) to the first station (feeding position) and enters the next cycle

2. The main technical parameters of the machine tool are shown in Table 1

Figure 1 machine tool structure diagram

Figure 2 machine tool sectional view

Table 1 main technical parameters of machine tool

3. Main innovations of machine tool

the main innovations of machine tool are as follows:

(1) this machine tool adopts special machine tool to complete deep hole processing, and the total investment is greatly reduced compared with the traditional method

(2) the processing efficiency is high. Taking the processing of four cylinder diesel engine cylinder block as an example, the length diameter ratio of processing deep holes can reach 20-30 (this machine tool reaches 20), and the beat can be stably controlled within 3 minutes

(3) drilling head mining 4. Main parameters: use the spindle structure of the high rigidity machining center, which makes the machining process easier when the machine is idle, and is conducive to improving the rigidity of the whole machine tool during high-speed cutting. The spindle center is reduced to the minimum to minimize the tipping torque generated during cutting

several experimental machines are introduced below for reference: (4) deep hole machining tools adopt advanced cemented carbide, which can realize high-speed and large feed processing, and greatly shorten the processing time. Compared with the traditional fried dough twist drill, although the initial investment is large, the durability of the tool is high and the machining accuracy is very stable. Once the cutting tools are worn, they are sharpened by professional manufacturers, and the overall accounting is lower than that of general fried dough twist drills. The axial force is very large during high-speed feeding, and the hydraulic tool handle is used to clamp the tool to ensure the stability during cutting

(5) both the spindle and the tool are equipped with internal cooling holes, and the high-pressure coolant is sprayed from the center of the tool, and enters the deep hole together with the tool. During the deep hole processing, the cooling is carried out at the same time, and the iron filings that are not easy to be discharged from the deep hole are flashed out of the hole, which solves the problem that the iron filings are difficult to be discharged in the deep hole processing and are easy to produce chip nodules

(6) adopt the process of pre drilling in the first station and deep drilling in the second station. As the guide hole of deep hole, pre drilling can be guided without drilling template, which realizes rigid drilling, greatly simplifies the structure of fixture, makes alignment and adjustment more convenient, and saves the work of manufacturing and replacing drill sleeve in the process of use

(7) the machine tool is equipped with a perfect cooling chip removal device. The coolant and iron chips are discharged into the cooling chip removal device from the chip removal port of the slide base. Most of the iron chips are taken away through the chip removal device, and then the fine iron chips are discharged through a high-precision filter. The filtering accuracy can reach 5 μ m. Ensure that the coolant is clean and prevent the spindle center from blocking. At the same time, a pressure sensor is connected in series on the control circuit. When the pressure exceeds the set value, it indicates that there is blockage in the coolant circuit, and then the pressure sensor transmits the signal to the system to make the system alarm, the machine tool stops acting, and the machine tool is safer to use

4. Conclusion

the machine tool has made a lot of improvements and innovations in structure, and the technical level and actual accuracy indicators have been significantly improved. It has passed the user's acceptance, and the machining accuracy of the machine tool meets the user's requirements