CN209936704U

CN209936704U - Ultrasonic cavitation auxiliary jet polishing system

Info

Publication number: CN209936704U
Application number: CN201920618902.XU
Authority: CN
Inventors: 曹中臣; 姜向敏; 张晓峰; 林彬; 张钱
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2020-01-14
Anticipated expiration: 2029-04-30

Abstract

The utility model discloses an ultrasonic cavitation auxiliary jet polishing system, which comprises an ultrasonic transducer and a shell; a cavity with an opening at the upper end is arranged in the shell; the ultrasonic transducer is sealed and covered on an opening at the upper end of the cavity; a polishing solution supply port is formed in the side face of the shell; a jet nozzle is arranged on the lower side of the shell; the polishing solution supply port and the jet nozzle are communicated with the cavity. The utility model discloses the mountable is at the headstock of digit control machine tool or install on industrial robot arm, utilizes ultrasonic transducer to make the polishing solution produce high-frequency oscillation and produce cavitation bubble to focus on the polishing solution after the cavitation in jet nozzle department, utilize the efflux to bump the surface that the mouth spouts high-pressure, fast-speed polishing solution to the work piece needs polishing, along with cavitation bubble's rapid rupture can increase the speed that granule striking work surface in the polishing solution, thereby improve the material removal efficiency of abrasive water jet.

Description

Ultrasonic cavitation auxiliary jet polishing system

Technical Field

The utility model relates to a fluid burnishing device, in particular to supplementary jet polishing system of ultrasonic cavitation.

Background

At present, with the development of modern optical technology, the demand of high-performance and high-quality optical parts is more and more urgent, and the requirements on processing equipment and processes of the high-quality optical parts are also higher and higher. Various machining methods have been studied to obtain a high-precision surface, and typical methods are plastic grinding, chemical polishing, float polishing, elastic emission machining, particle beam polishing, jet polishing, and the like. However, these typical machining methods either damage the machined surface of the component, or the machining efficiency is too low, or the controllability is too poor, and each of them has some defects, so that new machining methods are gradually proposed.

Abrasive water jet polishing is an ultra-precision machining technology which integrates current collector mechanics, nano material removal and surface technology and is developed on the basis of a water jet machining technology. The basic working principle is that a premixed polishing solution is sprayed onto the surface of a workpiece at a proper pressure and speed (the pressure is generally in a range of 4bar-20bar) by using an angle-adjustable nozzle, and the interaction between particles in suspension and the workpiece is utilized to carry out nano-removal of materials, so that the aims of correcting and flattening the surface shape of the polished workpiece surface are finally fulfilled. Compared with the traditional processing technology, the abrasive water jet polishing has the advantages of no tool abrasion, no thermal reaction, small reaction force, high processing flexibility and the like. Although abrasive particle water jet polishing technology can be used for ultra-precision machining of aspheric surface, free surface, microstructure surface and high-gradient and large-length-diameter ratio inner cavity surface devices, the removal efficiency of polishing materials is low (generally lower than 1 mm) due to unstable jet beam of the abrasive particle water jet polishing technology³Min) and the like, making it impossibleMeet the requirement of high-efficiency polishing of superhard materials such as polycrystalline diamond, silicon carbide and the like

Fluid Vibration Polishing (PVL) is different from a Polishing grinding disc adopted by the traditional ultra-smooth surface fluid Polishing technology, a workpiece is directly soaked in Polishing Liquid, high-frequency ultrasonic waves are radiated to the Liquid by an ultrasonic transducer, and particles in the Polishing Liquid are driven to wash the surface of the workpiece by a pressure field and a flow field generated by ultrasonic Vibration. When the sound pressure exceeds the cavitation threshold, a strong cavitation effect is generated, local energy concentration is generated near the surface of the workpiece, extreme phenomena such as high temperature, high pressure, shock waves and high-speed jet flows are caused, and the micro jet flows are matched with the high-frequency motion of abrasive particles to effectively remove the material. At present, for the fluid vibration polishing process, a plurality of ultrasonic transducers are mainly installed on the top or side of a polishing tank to form an ultrasonic transducer array, and a workpiece to be processed performs planetary motion in a polishing solution to maintain a certain uniformity. However, such fluid polishing devices also suffer from several disadvantages: the processed workpiece is completely immersed in the polishing tank, so that the excited abrasive and the excited jet flow can remove materials on all the surfaces of the whole workpiece, and the removal amount of all the parts is difficult to control, so that the current fluid vibration polishing device cannot perform high-quality correction on the surface of the workpiece.

Disclosure of Invention

The utility model provides an ultrasonic cavitation auxiliary jet polishing system which only polishes the surface of a workpiece needing polishing to solve the technical problem in the prior art.

The utility model discloses a solve the technical scheme that technical problem that exists among the well-known technique took and be: an ultrasonic cavitation assisted jet polishing system comprises an ultrasonic transducer and a shell; a cavity with an opening at the upper end is arranged in the shell; the ultrasonic transducer is sealed and covered on an opening at the upper end of the cavity; a polishing solution supply port is formed in the side face of the shell; a jet nozzle is arranged on the lower side of the shell; the polishing solution supply port and the jet nozzle are communicated with the cavity.

Further, the ultrasonic transducer comprises an upward-concave spherical piezoelectric ceramic plate; the piezoelectric ceramic piece is positioned above the opening at the upper end of the containing cavity.

Furthermore, the spherical focal length of the piezoelectric ceramic piece is 10-100 mm.

Further, the spherical focus of the piezoelectric ceramic piece is located in the center of the upper end of the jet nozzle.

Furthermore, the accommodating cavity is a conical accommodating cavity with a downward conical top, and a flow guide hole is formed in the conical top of the conical accommodating cavity; the jet flow nozzle is communicated with the diversion hole.

Further, the jet nozzle is detachably connected to the housing.

Furthermore, the jet nozzle is provided with a jet hole, and the diameter of the jet hole is 0.1-3 mm.

Further, the frequency range of the ultrasonic wave emitted by the ultrasonic transducer is 10KHz to 20 MHz.

Further, the shell is installed on a spindle box of the numerical control machine tool.

Further, the housing is mounted on an industrial robot arm.

The utility model has the advantages and positive effects that: the utility model discloses the mountable is at the headstock of digit control machine tool or install on industrial robot arm, utilizes ultrasonic transducer to make the polishing solution produce high-frequency oscillation and produce cavitation bubble to focus on jet nozzle department with the polishing solution after the cavitation, utilize jet nozzle to spout high-pressure, fast-speed polishing solution to the surface that the work piece needs to polish, along with cavitation bubble's rapid rupture can increase the speed that granule striking work piece surface in the polishing solution, thereby improve the material removal efficiency of abrasive water jet. The utility model is not only suitable for the surface finishing of the ultra-smooth surface, but also suitable for the surface processing and manufacturing of the microcosmic special appearance.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

fig. 2 is a schematic structural view of the piezoelectric ceramic plate of the present invention.

In the figure: 1. an ultrasonic power supply; 2. an ultrasonic transducer; 3. a housing; 4. a jet nozzle; 5. a workpiece; 6. a seal ring; 7. a polishing solution supply port; 8. a flow guide hole; 9. polishing solution; r, the spherical radius of the piezoelectric ceramic piece.

Detailed Description

For further understanding of the contents, features and effects of the present invention, the following embodiments are listed and will be described in detail with reference to the accompanying drawings:

referring to fig. 1 to 2, an ultrasonic cavitation assisted jet polishing system includes an ultrasonic transducer 2 and a housing 3; a cavity with an opening at the upper end is arranged in the shell 3; the ultrasonic transducer 2 is hermetically covered on an opening at the upper end of the cavity; a polishing solution supply port 7 is formed in the side surface of the shell 3; a jet nozzle 4 is arranged on the lower side of the shell 3; the polishing solution supply port 7 and the jet nozzle 4 are communicated with the containing cavity. The jet nozzle 4 is detachably connected to the housing 3, and both are screwed. The frequency range of the ultrasonic wave emitted by the ultrasonic transducer 2 can be 10KHz to 20 MHz.

The ultrasonic power supply 1 supplies electric energy to the ultrasonic transducer 2, the ultrasonic transducer 2 is arranged on the shell 3 through bolts, in order to prevent the polishing solution 9 from leaking, a bonding surface is sealed by a rubber sealing ring 6, and a polishing solution supply port 7 is formed in the side surface of the shell 3 and used for injecting the polishing solution 9 with certain pressure into an inner cavity of the shell 3; the jet nozzle 4 is arranged at the lower side of the shell 3, and the position of the jet nozzle 4 can be used as the focusing focal point position of the ultrasonic transducer 2; during the polishing process, the jet nozzle 4 is kept at a distance from the workpiece 5.

The ultrasonic transducer 2 may comprise an upwardly concave spherical piezoelectric ceramic plate; the ultrasonic transducer 2 is directly focused by using the spherical focusing principle. The piezoelectric ceramic plate can be ground into a spherical crown shape, or a spherical crown shape is formed by gluing dozens or even hundreds of planar piezoelectric ceramic plates. The spherical radius R of the piezoelectric ceramic piece can be set, and then the piezoelectric ceramic piece is processed or assembled according to the set value; the spherical piezoelectric ceramic plate can also be selected from the commercially available finished products.

The piezoelectric ceramic piece can be positioned above the opening at the upper end of the containing cavity. The spherical focal length of the piezoelectric ceramic piece can be 10-100 mm. In order to make the abrasive particles in the polishing solution 9 ejected from the jet nozzle faster and the polishing effect better, the spherical focus of the piezoelectric ceramic plate can be located at the center of the upper end of the jet nozzle 4.

In order to make the abrasive particles in the polishing solution 9 sprayed from the jet nozzle faster and the polishing effect better, the cavity can be a conical cavity with a downward conical top, and a flow guide hole 8 can be arranged at the conical top of the conical cavity; the jet nozzle 4 may communicate with the flow guiding hole 8. The jet nozzle 4 may be provided with jet holes, which may have a diameter of 0.1-3 mm. The upper end opening of the jet nozzle 4 can be a horn mouth; the diameter of the flow guide hole 8 is the same as that of the bell mouth at the upper end of the jet flow nozzle 4.

The shell 3 can be arranged on a main shaft box of a numerical control machine tool, and the jet flow nozzle 4 is always aligned to the surface of a part to be processed of the workpiece 5 through the combined motion of the workbench and the main shaft box. The housing 3 can also be arranged on a mechanical arm of an industrial robot, and the distance between the jet nozzle 4 and the surface of the workpiece 5 and the relative posture between the jet nozzle 4 and the surface of the workpiece 5 are controlled by adjusting the position of the mechanical arm.

The first application embodiment: in this example, the housing 3 of the present invention may be vertically mounted on a headstock above a numerical control machine tool table, the workpiece 5 is fixed on the machine tool table, and the jet nozzle 4 is moved to a suitable position above the surface of the workpiece 5 by the combined motion of the table and the headstock; pressurizing the polishing solution 9 mixed with particles in advance to 0.1-10MPa by using a pressure pump, injecting the pressurized polishing solution 9 into the shell 3 through a polishing solution supply port 7, starting an ultrasonic power supply 1, spraying the polishing solution 9 subjected to ultrasonic cavitation onto the surface of the workpiece 5, and eroding the surface of a processing area of the workpiece 5 by using the particles in the polishing solution 9 to remove the surface material of the workpiece 5. In the machining process, firstly, the residence time and the optimized machining track are calculated according to the initial surface type error of the workpiece 5, a numerical control machining program is generated, the machining program is guided into a machine tool, and the surface of the workpiece 5 is precisely polished.

Application example two:

in this example, can with the utility model provides a casing 3 installs on the industrial robot arm that can adjust the removal in a flexible way, controls the distance on

fluidic nozzle

4 and 5 surfaces of work piece and the relative gesture on

fluidic nozzle

4 and 5 surfaces of work piece through the adjustment arm. Therefore, the polishing device can flexibly meet the requirements of polishing the inner surfaces of different complex free-form surfaces and special-shaped cavities.

The utility model discloses a theory of operation: the utility model discloses combine abrasive water jet burnishing device and focused ultrasound's principle, produce high frequency vibration at the utilization ultrasonic transducer, and ultrasonic transducer 2 adopts spherical piezoceramics piece to have the characteristics of self-focusing, make polishing solution 9 in the casing 3 vibrate at high frequency under the sound field effect, and produce cavitation bubble, utilize abrasive water jet polishing high pressure, fast-speed characteristic, polishing solution 9 and the polishing particle that will contain cavitation bubble spout to treat 5 surfaces of processing work piece, the formation of cavitation bubble, granule striking surface speed in dynamics such as growth and fracture are 9 with higher speed polishing solution, thereby improve the efficiency of water jet polishing.

The ultrasonic transducer 2 adopts a spherical piezoelectric ceramic piece, the focusing distance of the spherical piezoelectric ceramic piece can be 10-100mm according to application requirements, and the focus position of the ultrasonic transducer 2 is positioned at the jet nozzle 4.

The frequency range of the ultrasonic wave emitted by the ultrasonic transducer 2 is between 10KHz and 20MHz, and due to different materials and concentrations of the polishing solution 9, the ultrasonic frequency for generating cavitation bubbles in the ultrasonic focusing wall body is different, and a proper frequency range can be selected according to application requirements.

Injecting a pre-prepared polishing solution 9 into the housing 3 at a certain pressure, wherein the polishing solution 9 can be cerium oxide, aluminum oxide, silicon oxide or nano-diamond particles, and the supply pressure range of the polishing solution 9 is as follows: 0.1-10Mpa, the range of the injection speed of the polishing solution 9 at the nozzle is as follows: 10-100 m/s.

The jet flow nozzle 4 in the polishing device is made of stainless steel, sapphire glass, ceramic or other pressure-resistant and corrosion-resistant materials, and the diameter range of the micropores of the jet flow nozzle 4 is as follows: 0.1-3 mm.

In the processing process, the material removal amount and the surface processing precision of a processing area can be controlled by controlling the ultrasonic vibration frequency, the distance between the nozzle and the workpiece 5, the spraying angle, the concentration of the polishing solution 9, the supply pressure of the polishing solution 9, the residence time of a processing point and the motion trail, so that the precise polishing process of the surface of the workpiece 5 is realized.

The above-mentioned embodiments are only used for illustrating the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention accordingly, the scope of the present invention should not be limited by the embodiment, that is, all equivalent changes or modifications made by the spirit of the present invention should still fall within the scope of the present invention.

Claims

1. An ultrasonic cavitation auxiliary jet flow polishing system is characterized by comprising an ultrasonic transducer and a shell; a cavity with an opening at the upper end is arranged in the shell; the ultrasonic transducer is sealed and covered on an opening at the upper end of the cavity; a polishing solution supply port is formed in the side face of the shell; a jet nozzle is arranged on the lower side of the shell; the polishing solution supply port and the jet nozzle are communicated with the cavity.

2. The ultrasonic cavitation-assisted jet polishing system of claim 1, wherein the ultrasonic transducer comprises an upwardly concave spherically shaped piezoceramic sheet; the piezoelectric ceramic piece is positioned above the opening at the upper end of the containing cavity.

3. The ultrasonic cavitation-assisted jet polishing system according to claim 2, wherein the spherical focal length of the piezoceramic wafer is 10-100 mm.

4. The ultrasonic cavitation-assisted jet polishing system according to claim 2, wherein the spherical focus of the piezoceramic wafer is centered on the upper end of the jet nozzle.

5. The ultrasonic cavitation auxiliary jet polishing system as claimed in claim 1, wherein the cavity is a conical cavity with a downward conical top, and a flow guide hole is formed at the conical top of the conical cavity; the jet flow nozzle is communicated with the diversion hole.

6. The ultrasonic cavitation-assisted jet polishing system of claim 1 in which the jet nozzle is detachably connected to the housing.

7. The ultrasonic cavitation-assisted jet polishing system as claimed in claim 1, wherein the jet nozzle is provided with an injection hole having a diameter of 0.1-3 mm.

8. The ultrasonic cavitation-assisted jet polishing system according to claim 1, wherein the ultrasonic transducer emits ultrasonic waves in a frequency range of 10KHz to 20 MHz.

9. The ultrasonic cavitation assisted jet polishing system of claim 1 in which the housing is mounted on a headstock of a numerically controlled machine tool.

10. The ultrasonic cavitation assisted jet polishing system of claim 1 in which the housing is mounted on an industrial robot arm.