A kind of single excitation ultrasonic elliptical vibratory burnishing device
Technical field
The invention belongs to surface of the work Finishing field, especially relate to a kind of burnishing device utilizing single excitation ultrasonic elliptical vibratory and mechanical reciprocation to combine.
Background technology
The surface quality of develop rapidly to workpiece of modern industry science and technology is had higher requirement, workpiece surface quality affects presentation quality and the function life-span of workpiece, and grinding and polishing is mould, engineering machinery, Medical Devices, the important means of some vital part Surface Machining in aerospace industry, in order to improve efficiency and the quality of grinding and polishing, publication number is the Ginding process that the patent of invention document of CN101362303A discloses a kind of mechanical reciprocating and ultrasonic vibration compound, it adopts mechanical reciprocating vibration and One-Dimensional Ultrasonic to vibrate the superimposed method driving surface of bistrique to workpiece and grinds, and then reach the object improving working (machining) efficiency and crudy, but due to the method employing is One-Dimensional Ultrasonic vibration, and mechanical reciprocating and ultrasonic vibration are in the same direction, its tool heads can only carry out polishing point-blank, therefore in use, still there is polishing efficiency on the low side, the uniform not problem of workpiece surface finish of grinding and polishing.
Ultrasonic elliptical vibratory has in fields such as UVC, ultra-sonic welded, ultrasonic grinding, ultrasonic polishing, linear ultrasonic motor and rotary ultrasonic motors to be applied more widely.Current researcher adopts extensional vibration mostly, twisting vibration, two kinds of vibration modes in flexural vibrations and radial vibration carry out compound to produce ultrasonic elliptical vibratory, the piezoelectric ceramic piece adopting two groups or more is needed to excite the two or more mode of oscillations producing and have certain phase difference, also be necessary for often group piezoelectric ceramic piece and be equipped with a road ultrasound-driven power supply signal, and need to control the phase difference between the ultrasound-driven power supply signal of each road, ultrasonic vibration system and Control system architecture complexity, manufacture difficulty is large, control difficulty is high, production cost is high, not easily realize microminiaturization, service behaviour is stable not, these problems constrain the application in the industrial production of ultrasonic elliptical vibratory transducer and popularization.
How to overcome the deficiency existed in above-mentioned ultrasonic vibration polishing technology and ultrasonic elliptical vibratory technology, and utilize novel single excitation ultrasonic elliptical vibratory technology, a kind of composite polishing device making tool heads realize reciprocating machine motion and the ultrasonic elliptic vibrations of single excitation is provided, the uniformity of further raising polishing efficiency and workpiece surface finish is main research of the present invention.
Summary of the invention
The invention provides a kind of novel list excitation ultrasonic elliptical vibratory burnishing device, object is to overcome the deficiency existed in existing ultrasonic vibration finishing method, the uniformity improving polishing efficiency and workpiece surface finish.
A kind of single excitation ultrasonic elliptical vibratory burnishing device, comprises overcoat, linear bearing, reciprocating drive mechanism, housing unit, the single-excitation ultrasonic oval vibration energy converter be placed in housing unit, elliptical vibration modal transducer and is arranged on the tool heads of elliptical vibration modal transducer front end.Described linear bearing is supported between housing unit and overcoat, and linear bearing is sliding straight bearing or rolling linear bearing.Described housing unit comprises front apron, inner sleeve and backboard; Described reciprocating drive mechanism one end is fixed on the backboard of housing unit, and the other end is fixing on the coat, and reciprocating drive mechanism is slider-crank mechanism, eccentric mechanism, screw-nut body, cylinder or hydraulic cylinder reciprocating drive mechanism.
Described single-excitation ultrasonic oval vibration energy converter entirety is in cylinder, it comprises bolt and is set in back shroud, piezoelectric ceramic piece, electrode slice and the front shroud on bolt successively, front shroud is provided with the ring flange connected with housing unit, back shroud, piezoelectric ceramic piece, electrode slice and front shroud are connected compression by bolt by back shroud and front shroud, constitute the energy conversion part of single-excitation ultrasonic oval vibration energy converter, the ultrasonic electric signal that ultrasonic-frequency power supply exports can be converted to the longitudinal ultrasonic vibration of single-excitation ultrasonic oval vibration energy converter.
Described elliptical vibration modal transducer and front shroud are made into the front end that is integrally provided in front shroud, or the welding of elliptical vibration modal transducer is arranged on the front end of front shroud.Elliptical vibration modal transducer comprises the composite construction of straight beam and cant beam formation, straight beam and cant beam are rectangle perpendicular to the cross section of its central axis, the central axis of straight beam and the central axes of single-excitation ultrasonic oval vibration energy converter, one end of straight beam connects with the front shroud of ultrasonic transducer, and the other end overhangs; The side of one end of cant beam and the front shroud displaced central axis line of ultrasonic transducer connects, the middle part of the other end and straight beam connects, the central axis of cant beam becomes 0-90 degree angle with the central axis of straight beam, straight beam and cant beam are arc transition with the connection place of ultrasonic transducer front shroud and connect, and the geometric centre axes of cant beam is parallel with polished surface of the work with the plane that the geometric centre axes of straight beam is formed.
The sub-assembly that elliptical vibration modal transducer is formed after being arranged on single-excitation ultrasonic oval vibration energy converter front end is called single excitation ultrasonic elliptical vibratory transducer, the elliptical vibration modal transducer mode of oscillation that to be the object of straight beam and cant beam composite construction be in order to change single-excitation ultrasonic oval vibration energy converter, make its longitudinal vibration mode frequency and flexural vibration mode frequency close to or equal; Due to the existence of oblique beam structure, the longitudinal ultrasonic vibration that single-excitation ultrasonic oval vibration energy converter produces is after being delivered to cant beam, a part of extensional vibration component and a part of flexural vibrations component is decomposed at cant beam root, the extensional vibration component decomposed when cant beam and after flexural vibrations component is delivered to straight beam, with the extensional vibration phase compound that straight beam is propagated, finally formed at straight beam end and there is the extensional vibration component of certain phase difference and the ultrasonic elliptical vibratory of flexural vibrations component compound.
Tool heads connects the front end being arranged on elliptical vibration modal transducer by welding, joint bolt or press plate mechanism; After ultrasonic vibrational energy is delivered to elliptical vibration modal transducer end from single-excitation ultrasonic oval vibration energy converter, be converted to the vertical curved composite ultrasonic elliptical vibratory of extensional vibration and the flexural vibrations compound with certain phase difference, be namely converted to the vertical curved composite ultrasonic elliptical vibratory of elliptical vibration modal transducer end; And driven tool head does ultrasonic elliptical vibratory together with elliptical vibration modal transducer end.
Single-excitation ultrasonic oval vibration energy converter is placed in housing unit, the ring flange of single-excitation ultrasonic oval vibration energy converter is arranged in the fovea superior seam of inner sleeve, front apron is arranged on the opposite side of ring flange, fixation is risen to whole single-excitation ultrasonic oval vibration energy converter, backboard is arranged on the other end that inner sleeve does not have seam, prevent the foreign material such as dust, iron filings from entering in housing unit, affect single-excitation ultrasonic oval vibration energy converter service behaviour; Compare the ultrasonic vibration polishing system that existing document is introduced, this list excitation ultrasonic elliptical vibratory burnishing device has that power capacity is large, energy conversion efficiency is high, structure is simple, easy to manufacture, cost is low, the rigidity of structure is large, control-driven system is simple and vibropolish stable performance such as to stablize at the advantage.The straight path that this invention becomes common One-Dimensional Ultrasonic vibratory tool head is in addition finished to the polishing of elliptical vibration track, within the unit interval, elliptical vibration track has increased substantially the motion path of tool heads, and significantly broaden the width of single ultrasonic vibration polishing, therefore effectively can improve the uniformity of polishing efficiency and workpiece surface finish.
Further, described single-excitation ultrasonic oval vibration energy converter only has one group of extensional vibration piezoelectric ceramic piece.
Further, described single-excitation ultrasonic oval vibration energy converter only needs a road ultrasonic electric signal excitation.
Further, the operating frequency range of described single-excitation ultrasonic oval vibration energy converter is 18kHz-40kHz.
Present invention employs mechanical oscillation MODAL TRANSFORMATION OF A mechanism and the extensional vibration of single-excitation ultrasonic oval vibration energy converter conversion is decomposed into the extensional vibration of straight beam, the extensional vibration of cant beam and flexural vibrations component, finally synthesize vertical curved composite ultrasonic elliptical vibratory at straight beam end, simplify the overall structure of single excitation ultrasonic elliptical vibratory polishing system, greatly reduce the complexity of vibrational system, reduce manufacture, assembly difficulty and production cost; This invention only needs a road control circuit and ultrasonic-frequency power supply to encourage in addition, control difficulty is low, avoid the complicated ultrasonic-frequency power supply development cost that two-phase or multiphase ultrasonic vibration is compounded to form elliptical vibration transducer, simplify control circuit and ultrasonic-frequency power supply structure, reduce control circuit and ultrasonic-frequency power supply cost, be easy to realize the integrated of control circuit and ultrasonic-frequency power supply, improve system works reliability, stable work in work, has a extensive future.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention.
Fig. 2 is the top view of structural representation of the present invention.
Fig. 3 is the front view of single excitation ultrasonic elliptical vibratory transducer in the present invention.
Fig. 4 is the top view of single excitation ultrasonic elliptical vibratory transducer in the present invention.
Fig. 5 is application example schematic diagram of the present invention.
Number in the figure illustrates: 1. bolt, 2. back shroud, 3. piezoelectric ceramic piece, 4. electrode slice, 5. front shroud, 6. ring flange, 7. elliptical vibration modal transducer, 8. tool heads, 9. front apron, 10. workpiece, 11. inner sleeves, 12. linear bearings, 13. backboards, 14. reciprocating drive mechanisms, 15. overcoats, 16. ultrasonic-frequency power supplies.
Detailed description of the invention
Shown in composition graphs 1,2,3,4, a kind of single excitation ultrasonic elliptical vibratory burnishing device, comprises overcoat 15, linear bearing 12, reciprocating drive mechanism 14, housing unit, the single-excitation ultrasonic oval vibration energy converter be placed in housing unit, elliptical vibration modal transducer 7 and is arranged on the tool heads 8 of elliptical vibration modal transducer 7 front end.Described linear bearing 12 is supported between housing unit and overcoat 15, and linear bearing 12 is sliding straight bearing.Described reciprocating drive mechanism 14 is slider-crank mechanism, and its one end is fixed on the backboard 13 of housing unit, and the other end is fixed on overcoat 15, and the amplitude of reciprocating drive mechanism 14 is 6mm.
Described housing unit comprises front apron 9, inner sleeve 11 and backboard 13; Described single-excitation ultrasonic oval vibration energy converter entirety is in cylinder, it comprises bolt 1 and is set in back shroud 2, piezoelectric ceramic piece 3, electrode slice 4 and the front shroud 5 on bolt 1 successively, front shroud 5 is provided with the ring flange 6 connected with housing unit, back shroud 2, piezoelectric ceramic piece 3, electrode slice 4 and front shroud 5 are connected compression by bolt 1 by back shroud 2 and front shroud 5, constitute the energy conversion part of single-excitation ultrasonic oval vibration energy converter, the ultrasonic electric signal that ultrasonic-frequency power supply 16 can be exported is converted to the longitudinal ultrasonic vibration of single-excitation ultrasonic oval vibration energy converter.Single-excitation ultrasonic oval vibration energy converter only has one group of extensional vibration piezoelectric ceramic piece 3, piezoelectric ceramic transducer section diameter 30mm, and piezoelectric ceramic piece 3 is PZT-8, is of a size of:
Ф 30 × Ф 15 × 5, the sheet number of piezoelectric ceramic piece 3 is 2.
Elliptical vibration modal transducer 7 and front shroud 5 are made into the front end that an one-piece parts is arranged on front shroud 5, elliptical vibration modal transducer 7 comprises the composite construction of straight beam and cant beam formation, straight beam and cant beam are rectangle perpendicular to the cross section of its central axis, the central axis of straight beam and the central axes of single-excitation ultrasonic oval vibration energy converter, one end of straight beam connects with the front shroud 5 of ultrasonic transducer, the other end overhangs, and the cross section length of side is 12
×12mm, long 72mm; The side of one end of cant beam and the front shroud 5 displaced central axis line of ultrasonic transducer connects, and the central axis distance of the connection place distance front shroud 5 of cant beam central axis and front shroud 5 is 25mm, and the middle part of the other end and straight beam connects, and the cross section length of side is 12
×12mm.The central axis of cant beam becomes 30 angles with the central axis of straight beam, straight beam and cant beam are arc transition with the connection place of ultrasonic transducer front shroud 5 and connect, transition arc radius is 5mm, and the geometric centre axes of cant beam is parallel with polished plane with the plane that the geometric centre axes of straight beam is formed.
Tool heads 8 is arranged on the front end of elliptical vibration modal transducer 7 by welding; After ultrasonic vibrational energy is delivered to elliptical vibration modal transducer 7 end from single-excitation ultrasonic oval vibration energy converter, be converted to the vertical curved composite ultrasonic elliptical vibratory of extensional vibration and the flexural vibrations compound with certain phase difference, be namely converted to the vertical curved composite ultrasonic elliptical vibratory of elliptical vibration modal transducer 7 end; And driven tool 8 does ultrasonic elliptical vibratory together with elliptical vibration modal transducer 7 end.
Single-excitation ultrasonic oval vibration energy converter is placed in housing unit, the ring flange 6 of single-excitation ultrasonic oval vibration energy converter is arranged in the fovea superior seam of inner sleeve 11, and front apron 9 is arranged on the opposite side of ring flange 6, plays fixation to whole single-excitation ultrasonic oval vibration energy converter, backboard 13 is arranged on the other end that inner sleeve 11 does not have seam
Intrinsic frequency after single-excitation ultrasonic oval vibration energy converter and elliptical vibration modal transducer 7 connect is 19.84KHz, impedance is 83 ohm, dynamic electric resistor is 19 ohm, ultrasonic-frequency power supply 16 output voltage range is 0-400V, current range is 0-4A, output frequency is 19.84 ± 0.01KHz, and ultrasonic-frequency power supply 16 has automatic frequency tracking function in designated frequency range.
Shown in composition graphs 5, during system cloud gray model, the electrode slice 4 of single-excitation ultrasonic oval vibration energy converter is connected with ultrasonic-frequency power supply 16, after the electrode slice 4 of single-excitation ultrasonic oval vibration energy converter accesses the signal of telecommunication of ultrasonic-frequency power supply 16 output, due to the inverse piezoelectric effect of piezoelectric ceramic piece 3, piezoelectric ceramic piece 3 will produce longitudinal ultrasonic vibration, namely the electric energy that ultrasonic-frequency power supply 16 exports is converted to longitudinal ultrasonic vibration by single-excitation ultrasonic oval vibration energy converter, and drive whole single-excitation ultrasonic oval vibration energy converter system to carry out longitudinal ultrasonic vibration, after ultrasonic vibrational energy is delivered to elliptical vibration modal transducer 7 end from single-excitation ultrasonic oval vibration energy converter, be converted to the vertical curved composite ultrasonic elliptical vibratory of extensional vibration and the flexural vibrations compound with certain phase difference, namely the vertical curved composite ultrasonic elliptical vibratory of elliptical vibration modal transducer 7 end is converted to, and driven tool 8 does ultrasonic elliptical vibratory together with elliptical vibration modal transducer 7 end.
After on-load voltage runs 10 minutes, single excitation ultrasonic elliptical vibratory burnishing device reaches stable vibration state, now the regulated output voltage of ultrasonic-frequency power supply 16 is 220V, electric current is 1.35A, use laser doppler vibrometer to record ultrasonic elliptical vibratory length semiaxis amplitude and be respectively 14.3 microns and 5.2 microns, and by the dual trace oscilloscope with lissajouf figure calculation function, graphic operation is carried out to the signal that laser doppler vibrometer records, the ultrasonic elliptical vibratory track that axial ratio is 2.73 can be obtained, meet the requirement of ultrasonic elliptical vibratory polishing completely.When driven tool 8 carries out compound motion work for reciprocating drive mechanism 14 and the ultrasonic ellipticity vibrational system of single excitation simultaneously, the motion polishing area of tool heads 8 comparatively One-Dimensional Ultrasonic Vltrasonic device improves about 5 times, and the uniformity of surface smoothness also improves 50%.