A kind of concretion abrasive ultrasonic machining device and method
Technical field
The invention belongs to Ultrasonic machining technology field, especially relate to a kind of concretion abrasive ultrasonic machining device and method.
Background technology
The hard brittle materials such as optical glass, pottery and carborundum possess superior physics, chemistry and mechanical performance, in boat
The industrial circles such as sky, electronics, automobile, metallurgy, biological engineering and national defence have obtained increasingly being widely applied.Electro-chemical machining and
Spark machined is difficult to non electrically conductive material, and Laser Processing can cause resistant to elevated temperatures hard brittle material to crack, and surpasses
Sound processing has proved to be the effective ways of hard brittle material forming.Ultrasonic machining is along certain side on instrument or workpiece
A kind of process of part forming is realized, by selecting different tool ends end to the ultrasonic activation applied higher than 20kHz
Face shape and abrasive material (being generally divided into free abrasive and two kinds of forms of concretion abrasive), it is possible to achieve the irregularly-shaped hole of hard brittle material adds
Work, flat surface grinding are processed.
Free abrasive Ultrasonic machining is that abrasive suspension is input to instrument and surface of the work, and abrasive particle is under the vibration of instrument
High-speed impact surface of the work.The shortcoming of this processing is: instrument itself can produce abrasion;During deep hole machining, abrasive suspension
Liquid is difficult to enter into machining area, and working (machining) efficiency is relatively low;The flowing of abrasive suspension makes machining accuracy also can reduce.
Concretion abrasive Ultrasonic machining is that abrasive material is sintered to tool surfaces, this processing method gram by soldering or electroplating technology
Take free abrasive suspension and between instrument and workpiece, circulate smooth and abrasive material to problems such as the abrasions of machining tool.In recent years
Coming, concretion abrasive Ultrasonic machining gradually replaces traditional free abrasive Ultrasonic machining.
At present, domestic existing operating force invariant control system controls Ultrasonic machining state, and this feed system uses dynamometry
Instrument or electronic balance indirect detection operating force thus control tool feeding speed.But, the machine tool structure of detection operating force is more
Complexity, the response speed of dynamometry instrument is the slowest, and during large-scale workpiece and fine Ultrasonic machining, operating force is much smaller than work
Part is conducted oneself with dignity, it is difficult to ensure the accuracy of detection of operating force.
Summary of the invention
It is an object of the invention to provide a kind of concretion abrasive ultrasonic machining device, it has simple in construction, response speed
The feature that fast and machining accuracy is high, to solve in prior art the problems referred to above present in concretion abrasive Ultrasonic machining.
Another object of the present invention is to provide a kind of concretion abrasive supersonic making method, the method is capable of large-scale work
Part or the SERVO CONTROL of fine Ultrasonic machining, have fast response time and the high feature of machining accuracy, to solve in prior art
The problems referred to above present in concretion abrasive Ultrasonic machining.
For reaching this purpose, the present invention by the following technical solutions:
A kind of concretion abrasive ultrasonic machining device, it includes XY axle feed arrangement, work nest, main shaft column, concretion abrasive
Instrument, Z axis servo feeding apparatus and ultrasound wave generation system, wherein, described work nest is arranged on described XY axle feed arrangement,
Place in described work nest workpiece to be processed and its in fill working solution, described ultrasound wave generation system include ultrasonic amplitude transformer,
Ultrasonic transducer and supersonic generator, described concretion abrasive instrument is connected to the bottom of described ultrasonic amplitude transformer, and described Z axis is watched
Taking feed arrangement to be arranged on main shaft column, described ultrasonic transducer is arranged on described Z axis servo feeding apparatus and with described
Ultrasonic amplitude transformer connects, and described supersonic generator electrically connects with described ultrasonic transducer, and described supersonic generator includes
For the collecting unit of the electric current and voltage that gather ultrasonic transducer two ends with for calculating the equiva lent impedance of Ultrasonic machining system
Processing unit, described processing unit the equiva lent impedance of calculating and impedance settings are compared after to concretion abrasive instrument
The output electric current of feed speed and/or supersonic generator is adjusted.
Especially, described concretion abrasive ultrasonic machining device also includes for keeping stable cold of concretion abrasive tool temperature
But system.
Especially, described cooling system use recirculated water cooling mode, it include circulating water chennel, circulating pump, circulation line and
Cooling spray, described circulating water chennel is connected in described work nest by circulation line, and described circulating pump passes through circulation line
Being connected with described cooling spray, described cooling spray is arranged at the side of described concretion abrasive instrument, and described circulating pump is by work
Make the feeding cooling spray of the working solution in groove carries out water-cooled to concretion abrasive instrument.
Especially, described cooling system uses air cooling way, and it includes air-cooled shower nozzle and blowing plant, described air-cooled
Shower nozzle is arranged at the side of described concretion abrasive instrument, and described blowing plant provides high-pressure blast cold air source pair to air-cooled shower nozzle
Concretion abrasive instrument carries out air-cooled.
Especially, it is bolted between described ultrasonic transducer and ultrasonic amplitude transformer;Described ultrasonic amplitude transformer is with solid
It is bolted between knot abrasive material tools.
Especially, the series resonance frequency that frequency is ultrasonic vibration system of described ultrasonic constant current source output electric current, work
The adjustable extent making current peak peak value is 280mA~1200mA, and maximum effective output is 75W, typical operating frequency:
20kHz~40kHz.
Especially, described series resonance frequency is 24kHz, and zero-load impedance is 40 Ω, and described concretion abrasive instrument end face shakes
Width adjustable extent is 2.5 μm~22 μm.
A kind of concretion abrasive supersonic making method, in workpiece process to be processed, by gathering ultrasonic transducer
Two ends electric current and voltage, calculate the equiva lent impedance of Ultrasonic machining system accordingly, and compare with impedance settings, and then controls consolidation
The feed speed of abrasive material tools and/or the output electric current of supersonic generator, by controlling the feed speed of concretion abrasive instrument
Control processing gap, control instrument end face amplitude by controlling the output electric current of supersonic generator.
Especially, described concretion abrasive supersonic making method also includes the behaviour cooling down described concretion abrasive instrument
Make, to eliminate the impact on the equiva lent impedance of Ultrasonic machining system of the concretion abrasive tool temperature.
Especially, described workpiece to be processed is nonconducting hard brittle workpiece, described hard brittle workpiece by silicon carbide ceramics,
Aluminium oxide ceramics, any one material of glass are made.
Beneficial effects of the present invention is, the most described concretion abrasive ultrasonic machining device is adapted to not leading
The hard brittle workpiece of electricity carries out irregularly-shaped hole processing and plane grinding, it makes use of equiva lent impedance and the work of Ultrasonic machining system
The relation of tool end face load, it may be assumed that during concretion abrasive Ultrasonic machining, the Ultrasonic machining system being under series resonance state
Equiva lent impedance increases along with the processing reduction in gap, the increase of the output electric current of ultrasonic constant current source.Have in a particular application
Have the advantage that
1) replace traditional operating force invariant control system by method based on equiva lent impedance, the signal of detection from
In ultrasonic transducer two ends, deadweight and shape with workpiece are unrelated, and therefore accuracy of detection is not affected by workpiece, can realize large-scale work
Part or the SERVO CONTROL of fine Ultrasonic machining;
2) traditional operating force invariant control system needs to place dynamometry instrument below workbench and carries out the survey of centripetal force
Amount, the present invention calculates the equiva lent impedance of Ultrasonic machining system by the output electric current of the supersonic generator that detects and voltage,
Need not dynamometry instrument, simplify machine tool structure;
3) by electric current and the equiva lent impedance of voltage calculating Ultrasonic machining system, the measurement ring at detection ultrasonic transducer two ends
Joint detection is the signal of telecommunication, therefore has faster response speed;
4), during rotary ultrasonic grinding plane, can shake by changing the output electric current control instrument end face of supersonic generator
Width so that the equiva lent impedance of Ultrasonic machining system keeps stable, and output signal is the signal of telecommunication, uses the execution of ultrasonic vibration system
The response speed of mechanism is faster;
5) by the detection electric current at ultrasonic transducer two ends and voltage calculate equiva lent impedance regulation instrument feed speed or
Control the output electric current of supersonic generator, thus control to process gap or tool amplitude, make equiva lent impedance maintain setting value,
The stability that improve concretion abrasive Ultrasonic machining process makes equiva lent impedance maintain setting value, improves that concretion abrasive is ultrasonic to be added
The stability of work process.
Accompanying drawing explanation
Fig. 1 is the structural representation of the concretion abrasive ultrasonic machining device that the specific embodiment of the invention 1 provides;
Fig. 2 is the carrying out opposite sex hole machined of the concretion abrasive ultrasonic machining device that the specific embodiment of the invention 1 provides
Process principle figure;
Fig. 3 is that the concretion abrasive ultrasonic machining device that the specific embodiment of the invention 1 provides carries out flat surface grinding processing
Process principle figure.
Detailed description of the invention
Further illustrate technical scheme below in conjunction with the accompanying drawings and by detailed description of the invention.
Referring to shown in Fig. 1, in the present embodiment, a kind of concretion abrasive ultrasonic machining device includes XY axle feed arrangement 1, work
Making groove 2, main shaft column 3, concretion abrasive instrument 4, Z axis servo feeding apparatus 5 and ultrasound wave generation system, described work nest 2 leads to
Cross base 6 to be arranged on described XY axle feed arrangement 1, place in described work nest 2 workpiece to be processed 7 and its in fill work
Liquid, described ultrasound wave generation system includes ultrasonic amplitude transformer 8, ultrasonic transducer 9 and supersonic generator 10, described concretion abrasive
Instrument 4 is bolted to the bottom of described ultrasonic amplitude transformer 8, and described Z axis servo feeding apparatus 5 is arranged at main shaft column 3
On, described ultrasonic transducer 9 is arranged on described Z axis servo feeding apparatus 5 and is connected with described ultrasonic amplitude transformer 8, described super
Sonic generator 10 electrically connects with described ultrasonic transducer 9, and civil power is converted into and ultrasonic transduction by described supersonic generator 10
The high-frequency ac signal of telecommunication that device 9 matches, excitation ultrasonic vibration system work, described ultrasonic transducer 9, ultrasonic amplitude transformer 8 and
Concretion abrasive instrument 4 forms ultrasonic vibration system, and ultrasonic transducer 9 converts electric energy to mechanical energy, will by ultrasonic amplitude transformer 8
Amplitude amplification focused energy, make abrasive particle and working solution with certain energy impact by the vibration of concretion abrasive instrument 4 end face
Workpiece.
Described supersonic generator 10 uses ultrasonic constant current source, the series connection that frequency is ultrasonic vibration system of output electric current
Resonant frequency, the adjustable extent of operating current peak-to-peak value is 280mA~1200mA, and error is within 2%, and maximum effectively exports
Power is 75W, typical operating frequency: 20kHz~40kHz.By ultrasonic transducer 9, ultrasonic amplitude transformer 8 and concretion abrasive instrument 4
The ultrasonic vibration system of composition is arranged on Z axis servo feeding apparatus 5, and the series resonance frequency of vibrational system is about 24kHz, empty
Carrying impedance is 40 Ω, and instrument end face adjustable amplitude adjusting range is 2.5 μm~22 μm.Concretion abrasive instrument 4 processing sections a diameter of
3mm, with No. 45 steel as matrix, is sintered in diamond particles on instrument end face by the way of soldering, abrasive particle 50 mesh of soldering.
Described Z axis servo feeding apparatus 5 includes motor driver, motor, screw mandrel and workbench, and minimum resolution is
1 μm, is provided pulse signal by DSP module for motor driver.
Described concretion abrasive ultrasonic machining device also includes for keeping the cooling system that concretion abrasive tool temperature is stable,
Described cooling system uses recirculated water cooling mode, and it includes circulating water chennel 11, circulating pump 12, circulation line 13 and cooling spray,
Described circulating water chennel 11 is connected in described work nest 2 by circulation line 13, and described circulating pump 12 is by circulation line 13
Being connected with described cooling spray, described cooling spray is arranged at the side of described concretion abrasive instrument 4, and described circulating pump 12 will
Working solution in work nest 2 is sent in cooling spray and concretion abrasive instrument 4 is carried out water-cooled, and meanwhile, the cavitation of water also may be used
With the removal of accelerated material, in time processing product is discharged machining area.
The ultrasonic constant current source of described supersonic generator 10 includes the electric current for gathering ultrasonic transducer 9 two ends and electricity
The collecting unit of pressure and for calculating the processing unit of equiva lent impedance of Ultrasonic machining system, described processing unit by calculate etc.
Imitate feed speed and/or the output of supersonic generator to concretion abrasive instrument 4 after impedance compares with impedance settings
Electric current is adjusted.
Refer to shown in Fig. 2, add man-hour workpiece to be processed 7 is carried out irregularly-shaped hole, constant ultrasonic Constant Electric Current is first set
The output electric current in source, during hole machined, the electric current at ultrasonic constant current source multi collect ultrasonic transducer 9 two ends and voltage, meter
Calculation equiva lent impedance is averaged, and after comparing with impedance settings, transmission pulse signal is to motor driver, thus controls work
The feed speed of tool, with adapt to thick, in, processing that essence is different gauged.Controlled plant when carrying out opposite sex hole machined is instrument
Processing gap between equilbrium position and the workpiece surface to be machined of end face, should control to process gap and shake less than instrument end face zero load
Width.In the course of processing, the energy accumulating of instrument causes temperature to raise, and the zero-load impedance of ultrasonic vibration system also will steeply rise,
For coolant, instrument is persistently rushed liquid with water and can eliminate the tool temperature impact on equiva lent impedance, meanwhile, the cavitation of water
Effect may also speed up the removal of material, and coolant washes away processing product in time and can ensure that processing is smoothed out.
Referring to shown in Fig. 3, add man-hour workpiece to be processed 7 is carried out flat surface grinding, workpiece need to carry out the fortune of X, Y-direction
Dynamic;Controlled plant is the amplitude of instrument end face, can change instrument end face by regulating the output electric current of ultrasonic constant current source
Amplitude, the program is applicable to flat surface grinding processing.Particularly, in the flat surface grinding course of processing, ultrasonic constant current source collection surpasses
The electric current at sonic transducer two ends and voltage, and calculate average impedance, after comparing with impedance settings, regulation output electric current, makes
Obtain Ultrasonic machining system equiva lent impedance and reach stable.The ultrasonic mill of big plane can be carried out by the motion of the X of workpiece, Y-direction
Cut processing.
Above example simply elaborates ultimate principle and the characteristic of the present invention, and the present invention is not limited by above-mentioned example,
Without departing from the spirit and scope, the present invention also has various change and change, and these changes and change both fall within
In scope of the claimed invention.Claimed scope is defined by appending claims and equivalent thereof.