CN1190288C - Method and equipment for drilling micro-holes with variable parameter vibration drill - Google Patents

Abstract

The invention discloses a device for vibrating microholes with variable parameters. The device is composed of a controller, a power supply, a stepping motor, a precision collet, and an outer sleeve. The outer sleeve is provided with a connecting shaft coupling, The screw support of the ball screw, the output shaft of the stepper motor is connected to the coupling, the other end of the coupling is connected to the ball screw, the ball screw and the DC high-speed motor are sleeved in the support of the spindle motor, and the support of the spindle motor passes through The pressure plate is integrated with the copper sleeve. The DC high-speed motor is fixed on the pressure plate and connected to the power supply. The copper sleeve at the lower end of the pressure plate is equipped with piezoelectric ceramics and springs. The output shaft of the DC high-speed motor is connected to the main shaft. The precision spring chuck fixes the drill bit on the High-speed precision spindle. This method uses different processing parameters according to the different drilling stages in each drilling process. The drilling stage can be divided into three stages: the drilling stage, the drilling stage, and the drilling stage. The processing parameters are set as follows: Drill bit vibration frequency, drill bit vibration amplitude, drill bit rotation speed, drill bit feed speed four parameters.

Description

Equipment for Vibration Drilling Microholes with Variable Parameters

Technical field

The invention relates to a device for processing microholes, in particular to a device for vibrating microholes with variable parameters.

Background technique

In aviation, aerospace, automobile and other industrial fields, a large number of parts have micro-hole processing technology requirements with large aspect ratio. The processing quality of micro-holes, such as surface roughness, shape accuracy, and export burrs, are directly related to product quality. At present, the main methods of processing micro holes (diameter less than 1mm) at home and abroad are: ordinary drilling, high-speed drilling, EDM, EDM composite ultrasonic vibration processing and laser processing. There are some problems in these processing methods, such as the micro-hole surface of EDM and laser processing has a work-hardened layer, and the shape accuracy is not high. In addition, process equipment for vibrating micro-hole machining has also appeared at home and abroad, but its existing problems are poor flexibility and low degree of automation. When machining micro-holes, it is impossible to select appropriate processing parameters according to different processing stages, such as speed and vibration amplitude. , vibration product rate and feed rate, etc., in order to further improve the processing quality of micro-holes and reduce the process route, the inventors proposed a method and equipment for variable-parameter vibration drilling micro-holes, which can effectively improve the flexibility of processing technology , select the appropriate processing parameters for different micro-holes and parts materials, at the same time, the equipment has a compact structure design, convenient and flexible installation, and can be applied to many occasions.

Contents of Invention

The purpose of the present invention is to provide a special processing method different from the traditional drilling process, which is to make the drilling tool produce an axial vibration on the basis of the traditional drilling process, thereby effectively improving the processing conditions, improving the quality of micro-hole processing and Efficiency, especially for the micro-hole drilling of difficult-to-machine materials, can effectively solve processing technology problems and improve automation level and flexibility.

A device for vibrating microholes with variable parameters of the present invention is composed of a controller, a power supply, a stepping motor, a collet, and an outer sleeve, and the outer sleeve is provided with a shaft coupling and a ball screw. Screw support, the output shaft of the stepper motor is connected to the coupling, the other end of the coupling is connected to the ball screw, the ball screw and the DC high-speed motor are set in the main shaft motor support, and the main shaft motor support is connected to the copper sleeve through the pressure plate Connected as a whole, the DC high-speed motor is fixed on the pressure plate and connected to the power supply. The copper sleeve at the lower end of the pressure plate is equipped with piezoelectric ceramics and springs. The output shaft of the DC high-speed motor is connected to the high-speed precision spindle, and the spring chuck fixes the drill bit on the high-speed precision spindle. superior.

In the device for vibrating micro-holes with variable parameters, the output shaft of the stepping motor drives the ball screw to rotate through the coupling, and the ball screw converts the rotary motion into a linear motion in the axial direction supported by the main shaft motor. Together with the spring, a certain pre-tightening force is applied to the piezoelectric ceramics, which drives the high-speed precision spindle to generate axial feed, and provides axial feed for drill cutting.

The vibration-drilling equipment for micro-holes with variable parameters is provided by piezoelectric ceramics to generate 1-1000 Hz low-frequency vibration as the excitation source.

The device for drilling microholes with variable parameter vibration is characterized in that the low-frequency vibration generated by piezoelectric ceramics directly excites the high-speed precision spindle to generate a response with an amplitude of 1-10 μm.

In the device for vibrating micro-holes with variable parameters, the spring clip adopts a precision spring collet, which ensures the good rotation accuracy of the drill bit when installing the drill bit.

The above-mentioned equipment for vibrating micro-holes with variable parameters uses a coaxial spindle feed method, and a stepping motor directly drives a ball screw to drive a high-speed precision spindle, piezoelectric ceramics, and a DC high-speed motor to feed together.

The invention adopts a coaxial feeding device, which has the advantages of small volume, simple and compact structure, and stable feeding. The equipment can be installed on any rack, and the axis can be oriented to any position, which greatly improves the flexibility and reliability of equipment application. .

Description of drawings

Fig. 1 is a schematic diagram of the equipment structure of the present invention.

Fig. 2 is a schematic diagram of installing the equipment of the present invention on a common drilling operation frame.

Fig. 3 is a comparative diagram of the axial force of the equipment drilling micro-holes of the present invention and common micro-hole drills.

In the figure: 1. Stepping motor 2. Outer sleeve 3. Ball screw 4. Controller 5. Power supply 6. DC high-speed motor 7. Piezoelectric ceramics 8. High-speed precision spindle 9. Spring 10. Copper sleeve 11. Precision Spring chuck 12. Coupling 13. Spindle motor support 14. Press plate 15. Shelf

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

Please refer to Fig. 1, a kind of variable parameter vibration drilling microhole equipment of the present invention is made up of controller 4, power supply 5, stepper motor 1, precision collet 11, outer sleeve 2, and its outer sleeve The barrel 2 is provided with a screw support connecting the coupling 12 and the ball screw 3, the output shaft of the stepping motor 1 is connected to the coupling 12, and the other end of the coupling 12 is connected to the ball screw 3, the ball screw Bar 3, DC high-speed motor 6 is set in the spindle motor support 13, the spindle motor support 13 is integrated with the copper sleeve 10 through the pressure plate 14, the DC high-speed motor 6 is fixed on the pressure plate 14 and connected to the power supply 5, the copper sleeve at the lower end of the pressure plate 14 10 is provided with piezoelectric ceramics 7 and spring 9, the output shaft of DC high-speed motor 6 is connected with high-speed precision main shaft 8, and the precision collet 11 fixes the drill bit on the high-speed precision main shaft 8. By applying an AC voltage of 1 to 1000 Hz to the piezoelectric ceramic 7, the piezoelectric ceramic 7 will expand and contract at the same frequency, and finally directly push the high-speed precision spindle 8 to generate axial vibration as a whole, and adjust the driving frequency and driving voltage of the power supply 5 through the controller 4 , can make the drill bit vibrate with different frequencies and amplitudes in the axial direction. The main shaft structure of the present invention adopts the method of exciting the high-speed precision main shaft 8 on the piezoelectric ceramic 7. Since the high-speed precision main shaft 8 is very light, it is easy to be excited and generate a large amplitude. The maximum speed of the high-speed precision spindle 8 can reach 30,000r/min, and it is equipped with a precision collet 11, which can ensure the rotation accuracy of the drill bit to reach 1 μm. The spindle driving motor of the present invention selects a stepless variable speed DC high-speed motor 6, and the rotational speed of the DC high-speed motor can be adjusted through the controller 4. In order to prevent the drill bit from being damaged due to uneven feeding during processing, the present invention adopts a coaxial feeding method. This feeding method is directly driven by the stepping motor 1. The ball screw 3 drives the copper sleeve 10 to follow the DC high-speed The motor 6, the piezoelectric ceramic 7, the high-speed precision spindle 8, and the spring 9 feed together, and the minimum feed is 1 μm for one control pulse, and there is no crawling phenomenon.

In the present invention, the method of drilling microholes is to select different processing parameters according to the different stages of the drilling process, and the drilling process includes three stages: the drilling stage, the drilling stage, and the drilling stage. In the drilling stage, it is required to ensure that the drill bit has a high center of rotation and enter the drill smoothly; in the drilling stage, it is necessary to ensure smooth chip breaking and chip removal, and the coolant can better cool and lubricate the drill bit and improve the life of the drill bit; in the drilling stage It is required that the exit burr is small, and the drilling force will not suddenly increase and cause the drill bit to break. For this reason, different processing parameters must be selected in these three stages. The processing parameters include: spindle speed, feed speed, drill bit vibration frequency, and drill bit vibration amplitude.

In the present invention, the drilling-in stage is set from the surface of the workpiece to the hole depth of 0.5mm, the middle stage of drilling is set from the hole depth of 0.5mm to the place 0.5mm away from the bottom surface of the workpiece, and the drilling stage is set at the position where the drill bit is 0.5mm away from the bottom surface of the workpiece; According to the divided three drilling stages, combined with the workpiece material and drilling process requirements, set the processing parameters in the following ranges: vibration frequency (1~1000Hz), vibration amplitude (1~10μm), spindle speed (0~27000rpm) , Feed speed (1 ~ 20μm/r).

The variable parameter vibration micro-hole drilling technology adopted in the present invention can enable different processing parameters to be selected at different drilling stages when drilling micro-holes, especially when drilling difficult-to-machine materials and composite materials, and the parameter selection range is very wide , To ensure the processing quality and improve the processing efficiency. Moreover, variable parameter processing can enable the device of the present invention to be widely used, and the flexibility is greatly improved.

The present invention adopts piezoelectric ceramics 7 to vibrate the high-speed precision spindle 8 to vibrate in the way that the drill bit 11 generates axial vibration. The advantage of this structure is that the vibrating body is light in weight, easy to vibrate, and the vibrating body is small in size, high in power, and The compact structure can reduce the volume of the whole equipment.

The invention adopts the coaxial feeding device, which has the advantages of small volume, simple and compact structure, and stable feeding. The equipment can be installed on any rack, and the axis can be oriented to any position, which greatly improves the flexibility and reliability of equipment application. sex.

As shown in Figure 3, it is a comparison diagram of the axial force between the micro-hole drilling equipment with variable parameter vibration and ordinary micro-hole drilling. It can be seen from the figure that the axial force of variable-parameter vibration micro-hole drilling is greatly It is reduced, and the change is stable, especially in the drilling and drilling stages, there is no stage of sudden increase in axial force, which is conducive to improving the life of the drill bit and reducing the exit burr. It can be seen from specific examples that the present invention can effectively improve the processing quality and the life of the drill bit through variable parameter vibration drilling.

The variable-parameter vibration drilling micro-hole drilling equipment of the present invention can be installed on the shelf 15 of the common bench drill, and can conveniently replace the common bench drill to realize the variable-parameter vibration micro-hole drilling equipment, and the degree of automation is greatly improved.

For example: Drill a hole with a diameter of 0.5 mm on No. 45 steel material, and apply an AC drive voltage with a frequency of 500-1000 Hz and 600 v to the piezoelectric ceramic 7 to make the high-speed precision spindle 8 produce axial vibration with an amplitude of 3-7 μm . The parameters of the drilling stage (vibration frequency 500Hz, amplitude 7μm, rotating speed 23000r, feed speed 1μm/r) and the parameters of the drilling stage (vibration frequency 750Hz, amplitude 5μm, rotating speed 20000r, feed speed) are respectively set by the controller 4. 2μm/r) and the parameters of the drilling stage (vibration frequency 1000Hz, amplitude 3μm, rotation speed 20000r, feed rate 0.5μm/r), and then start drilling micro-holes. The invention can process microholes with a diameter of 0.1 mm to 2 mm, the aspect ratio of the microholes can reach 20:1, the life of the drill bit can be increased by more than 5 to 10, and the cutting force can be reduced by more than half.

The equipment of the invention effectively improves the processing conditions, improves the quality and efficiency of micro-hole processing, and can be effectively solved especially for the micro-hole drilling of difficult-to-machine materials, and improves the automation level and flexibility.

Claims (6)

1. the equipment of a variable parameter vibration drilling micropore, comprise controller, power supply, stepper motor, collet, outer sleeve (2), it is characterized in that: be provided with connection shaft coupling (12) in the outer sleeve (2), the leading screw of ball-screw (3) supports, the output shaft of stepper motor (1) is connected on the shaft coupling (12), the other end of shaft coupling (12) connects ball-screw (3), ball-screw (3), direct current high-speed electric expreess locomotive (6) is enclosed within spindle motor and supports in (13), spindle motor supports (13) and fuses by the same copper sheathing of pressing plate (14) (10), direct current high-speed electric expreess locomotive (6) is fixed on pressing plate (14) and goes up and connect power supply (5), be provided with piezoelectric ceramics (7) and spring (9) in the copper sheathing (10) of pressing plate (14) lower end, the output shaft of direct current high-speed electric expreess locomotive (6) connects high speed and precision main shaft (8), and collet (11) is fixed on drill bit on the high speed and precision main shaft (8).

2. the equipment of variable parameter vibration drilling micropore according to claim 1, it is characterized in that: stepper motor (1) output shaft drives ball-screw (3) by shaft coupling (12) and rotates, ball-screw (3) is converted into the rectilinear motion that spindle motor supports the axis direction of (13) with gyration, acting in conjunction by pressing plate (14) and spring (9), piezoelectric ceramics (7) is applied certain pretightning force, drive high speed and precision main shaft (8) and produce axial feed, for bit cutting provides axial feed.

3. the equipment of variable parameter vibration drilling micropore according to claim 1 is characterized in that: exciting source adopts piezoelectric ceramics (7) to produce 1～1000Hz low-frequency vibration and provides.

4. the equipment of variable parameter vibration drilling micropore according to claim 1 is characterized in that: the low-frequency vibration direct-drive high speed and precision main shaft (8) that piezoelectric ceramics (7) produces produces the response of 1～10 μ m amplitude.

5. the equipment of variable parameter vibration drilling micropore according to claim 1 is characterized in that: collet adopts precision spring chuck (11), has guaranteed to install the good drill bit rotating accuracy of drill bit.

6. drilling device according to claim 5, it is characterized in that: the axis feeding mode of coaxial-type, directly drive the mode of ball-screw (3) by stepper motor (1), drive high speed and precision main shaft (8), piezoelectric ceramics (7), together feeding of direct current high-speed electric expreess locomotive (6).

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