Ultrasonic processing equipment for high-hardness and brittle materials

Abstract

The present invention relates to the technical field of manufacturing equipment, and specifically to an ultrasonic processing device for high-hardness and brittle materials, comprising an ultrasonic electric spindle, the ultrasonic electric spindle comprising a rotating shaft, the rotating shaft comprising an amplitude-changing section and an adjustment section; the amplitude-changing section comprising a transition cylinder; the transition cylinder comprising a first transition cylinder and a second transition cylinder, which, when mounted by connecting bolts, form an annular groove between the two, in which an annular piezoelectric plate is mounted; the upper surface of the second transition cylinder comprises a load-bearing bolt for mounting an ultrasonic component; the lower surface of the adjustment section comprises an adjustment groove, in which a counterweight ball and an electro-hydraulic adjustment member are located. The ultrasonic electric spindle further comprises a control unit and a power supply unit, the control unit analyzing the axial force exerted on the tool and controlling the electrical conduction of the electro-hydraulic adjustment member. The present invention can dynamically adjust the resonance parameters of the ultrasonic spindle based on the real-time force data of the tool during actual machining, thereby improving machining efficiency and quality.

Description

Technical Field

[0001] The invention belongs to the technical field of manufacturing equipment and relates to ultrasonic processing equipment for high-hardness and brittle materials. Background Art

[0002] Ultrasonic vibration-assisted machining is a precision machining method that has great advantages in machining hard and brittle materials that are difficult to machine. It has outstanding advantages such as low machining stress, low machining temperature and small deformation of the workpiece, which can effectively improve machining accuracy and reduce the surface roughness of the workpiece, and can effectively process difficult-to-machine high-hardness and brittle materials. During the machining process, the energy output by the ultrasonic generator drives the tool to generate high-frequency mechanical vibration through the transducer and the amplitude rod, thereby producing a cutting effect on the workpiece. As an important component of ultrasonic machining equipment, the ultrasonic spindle has an important influence on the quality of ultrasonic machining. For example, patent document CN205362704U discloses an ultrasonic spindle. Although it can effectively machine hard and brittle materials, its vibration parameters are often constant and can only be limited to machining several or even one material. It is suitable for several or even one tool material and diameter, and has poor versatility, or cannot be adjusted in real time according to the changes in the axial force during the actual machining process. The machining quality and efficiency need to be improved. Summary of the Invention

[0003] In order to solve the problems in the prior art, the present invention provides an ultrasonic processing device for high-hardness and brittle materials.

[0004] The technical solution adopted in the present invention is:

[0005] An ultrasonic processing device for highly hard and brittle materials, comprising an ultrasonic electric spindle;

[0006] The ultrasonic electric spindle comprises a housing and a rotating shaft; the rotating shaft comprises, from bottom to top, an amplitude-changing section, an adjustment section, and a shaft core; a stator assembly is fixed on the inner wall of the housing; a rotor assembly is fixed on the shaft core at a position corresponding to the stator assembly, and the stator assembly and the rotor assembly are mounted together;

[0007] The amplitude changing section is composed of a tool head, an amplitude changing cone, and a transition cylinder from bottom to top, and the central axes of the three are located on the same straight line; the tool head is used to install the tool;

[0008] The transition cylinder includes a first transition cylinder and a second transition cylinder;

[0009] The first transition cylinder and the amplitude-changing cone are integrally formed; a connecting bolt is fixed to the upper surface of the first transition cylinder away from the amplitude-changing cone, and an annular protrusion is provided at the bottom of the connecting bolt along the vertical axis direction;

[0010] The lower surface of the second transition cylinder is provided with a bolt hole matching the connecting bolt. When the first transition cylinder and the second transition cylinder are installed by the connecting bolt, an annular groove is formed between the first transition cylinder and the second transition cylinder; an annular piezoelectric piece matching the shape of the annular groove is installed in the annular groove;

[0011] A bearing bolt is fixed on the upper surface of the second transition cylinder, and an ultrasonic component is sleeved on the bearing bolt. The ultrasonic component includes a plurality of piezoelectric ceramics and a plurality of electrode sheets stacked alternately;

[0012] The amplitude-changing section is coaxially fixed to the adjustment section by means of load-bearing bolts;

[0013] The lower surface of the adjustment section is provided with a plurality of adjustment grooves, which are radially and centrally symmetrically arranged on the lower surface of the adjustment section. Each adjustment groove contains an electro-adjustable member and at least one weighted ball. When the electro-adjustable member is not energized, the weighted ball is brought close to the outer end of the adjustment groove due to centrifugal force when the ultrasonic electric spindle rotates.

[0014] The ultrasonic electric spindle further comprises a control unit and a power supply unit for providing energy to the ultrasonic component and the electro-regulator;

[0015] The longitudinal ultrasonic wave generated by the ultrasonic component passes through the transition cylinder and the amplitude variation cone in turn and is transmitted to the tool head and the tool. When the tool is working, the piezoelectric piece is also affected by the axial force. The control unit collects the electrical signal of the piezoelectric piece and then analyzes the axial force exerted on the tool.

[0016] The control unit is configured to: when analysis shows that the axial force exerted on the tool exceeds a predetermined range, control the electro-adjustable component to be electrically conductive, thereby changing the position of the counterweight ball in the adjustment groove to change the mass distribution of the ultrasonic electric spindle, thereby changing the resonance parameters, reducing the ultrasonic resonance amplitude, and ensuring processing accuracy and quality.

[0017] Furthermore, the electro-adjustable component includes a conductive layer, a dielectric layer, and a conductive layer in sequence. The two conductive layers are electrically connected to the power supply part respectively. The dielectric layer expands after being energized, thereby causing the electro-adjustable component to expand and stretch, thereby supporting the counterweight ball to move a certain distance in the adjustment groove.

[0018] Furthermore, the load-bearing bolt and the ultrasonic component are separated by an insulating sleeve.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention uses the amplitude variation section, the adjustment section, and the control section to measure the axial force exerted on the tool in real time during the tool processing process, and dynamically adjusts the resonance parameters of the ultrasonic spindle based on the measurement results, thereby further improving the processing efficiency and processing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1-Figure 2 is a schematic diagram of the ultrasonic electric spindle of the present invention;

[0022] Figure 3 is a schematic diagram of the amplitude variation section of the present invention;

[0023] Figure 4-Figure 5 are schematic diagrams of the first transition cylinder and the second transition cylinder of the present invention respectively;

[0024] Figure 6 is a schematic diagram of the adjustment section of the present invention;

[0025] Figure 7-Figure 8 This is a schematic diagram of the position change of the distribution ball in the adjustment slot before and after the electro-adjusting element is turned on;

[0026] 1- Housing 2- Stator assembly 3- Rotor assembly 4- Amplitude change section 5- Adjustment section 6- Shaft core 7- Tool head 8- Amplitude change cone 9- First transition cylinder 10- Second transition cylinder 11- Connecting bolt 12- Annular protrusion 13- Bolt hole 14- Annular piezoelectric piece 15- Bearing bolt 16- Ultrasonic component 17- Piezoelectric ceramic 18- Electrode piece 19- Adjustment groove 20- Counterweight ball 21- Electro-induced adjustment element 22- Insulating sleeve DETAILED DESCRIPTION

[0027] In order to further understand the features, technical means, specific objectives and functions achieved by the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] like Figures 1-8 As shown, an ultrasonic processing device for high-hardness and brittle materials includes an ultrasonic electric spindle; the ultrasonic electric spindle includes a housing 1 and a rotating shaft; the rotating shaft comprises, from bottom to top, an amplitude variation section 4, an adjustment section 5, and a shaft core 6; a stator assembly 2 is fixed to the inner wall of the housing 1; a rotor assembly 3 is fixed to the shaft core 6 at a position corresponding to the stator assembly 2, and the stator assembly 3 and rotor assembly 2 are mounted together;

[0029] The amplitude changing section 4 is composed of a tool head 7, an amplitude changing cone 8, and a transition cylinder from bottom to top, and the central axes of the three are located on the same straight line; the tool head 7 is used to install the tool;

[0030] The transition cylinder includes a first transition cylinder 9 and a second transition cylinder 10; the first transition cylinder 9 is integrally formed with the amplitude variation cone 8; a connecting bolt 11 is fixed to the upper surface of the first transition cylinder 9 away from the amplitude variation cone 8, and the bottom of the connecting bolt 11 is provided with an annular protrusion 12 along the vertical axis direction; the lower surface of the second transition cylinder 10 is provided with a bolt hole 13 matching the connecting bolt, and when the first transition cylinder 9 and the second transition cylinder 10 are installed by the connecting bolt 11, an annular groove is formed between the first transition cylinder 9 and the second transition cylinder 10; an annular piezoelectric piece 14 adapted to the shape of the annular groove is installed in the annular groove; the annular piezoelectric piece 14 can be composed of nylon gaskets, piezoelectric materials, and nylon gaskets stacked in sequence; a load-bearing bolt 15 is fixed to the upper surface of the second transition cylinder 10, and an ultrasonic component 16 is mounted on the load-bearing bolt 15, and the ultrasonic component 16 includes a plurality of piezoelectric ceramics 17 and a plurality of electrode sheets 18 stacked alternately.

[0031] The amplitude variation section 4 is coaxially fixed to the adjustment section 5 by a load-bearing bolt 15; a plurality of adjustment grooves 19 are provided on the lower surface of the adjustment section 5, and the adjustment grooves 19 are radially and centrally symmetrically arranged on the lower surface of the adjustment section 5. Each adjustment groove 19 contains an electro-adjustable member 21 and at least one counterweight ball 20. When the electro-adjustable member 21 is not energized, the counterweight ball 20 is close to the outer end of the adjustment groove 19 due to centrifugal force when the ultrasonic electric spindle rotates.

[0032] The ultrasonic electric spindle further includes a control unit (not shown in the figure) and a power supply unit (not shown in the figure) for providing energy to the ultrasonic component 16 and the electro-regulator 21 .

[0033] The longitudinal ultrasonic wave generated by the ultrasonic component 16 passes through the transition cylinder and the amplitude-changing cone 8 in sequence and is transmitted to the tool head 7 and the tool. When the tool is working, the annular piezoelectric piece 14 is subjected to the axial force to generate an electrical signal. The control unit collects the electrical signal of the annular piezoelectric piece 14 and then analyzes the axial force exerted on the tool.

[0034] The control unit is configured to: when it is analyzed that the axial force exerted on the tool exceeds a predetermined range, control the electro-adjustable member 21 to be electrically conductive, thereby changing the position of the counterweight ball 20 in the adjustment groove 19 to change the mass distribution of the ultrasonic electric spindle, thereby changing the resonance parameters, reducing the ultrasonic resonance amplitude, and ensuring processing accuracy and quality.

[0035] Furthermore, the electro-adjustable element 21 includes a conductive layer, a dielectric layer, and a conductive layer in sequence. The two conductive layers are electrically connected to the power supply part respectively. The dielectric layer expands after being energized, thereby causing the electro-adjustable element 21 to expand and stretch, thereby supporting the counterweight ball 20 to move a certain distance in the adjustment groove 19. The conductive layer is made of a hard metal material, and the dielectric layer is PDMS doped with titanium dioxide particles.

[0036] Furthermore, the load-bearing bolt 15 and the ultrasonic component 16 are separated by an insulating sleeve 22 .

[0037] The working principle of the present invention is as follows: According to the principle of piezoelectric force measurement, when the stress acting on the piezoelectric material changes, that is, the axial force exerted on the tool changes, due to the positive piezoelectric effect, the piezoelectric material will generate a charge q = dσ, where σ is the stress exerted on the piezoelectric material, and d is the isotropic piezoelectric coefficient. The generated charge q corresponds one-to-one to the axial force. By processing the electrical signal, the axial force exerted on the tool can be obtained. The longitudinal ultrasonic wave generated by the ultrasonic component 16 passes through the transition cylinder and the amplitude-changing cone 8 in turn and is transmitted to the tool head 7 and the tool. When the tool is working, the annular piezoelectric piece 14 is simultaneously affected by the ultrasonic wave and the axial force. The control unit collects the electrical signal of the annular piezoelectric piece 14 and then analyzes the axial force exerted on the tool. The control unit presets the range of the axial force according to the processing accuracy and quality requirements. When the control unit analyzes that the axial force exerted on the tool exceeds the preset range, the electro-magnetic adjustment member 21 is controlled to be electrically conductive. At this time, the electro-magnetic adjustment member 21 expands and stretches after being energized, thereby supporting the counterweight ball 20 to move a certain distance in the adjustment groove 19. After the distance is moved, the mass distribution of the ultrasonic electric spindle is changed, thereby changing the resonance parameters, reducing the ultrasonic resonance amplitude, and controlling the axial force within the preset range to ensure processing accuracy and quality.

[0038] The above embodiments merely represent one or several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An ultrasonic processing device for high-hardness and brittle materials, comprising an ultrasonic electric spindle, the ultrasonic electric spindle comprising a housing and a rotating shaft; characterized in that: The rotating shaft comprises, from bottom to top, an amplitude changing section, an adjusting section and a shaft core; A stator assembly is fixed on the inner wall of the housing, and a rotor assembly is fixed on the shaft core at a position corresponding to the stator assembly, and the stator assembly and the rotor assembly are mounted together; The amplitude variation section comprises, from bottom to top, a tool head, an amplitude variation cone, and a transition cylinder, and the central axes of the three are located on the same straight line; the tool head is used to install a tool; the transition cylinder comprises a first transition cylinder and a second transition cylinder; the first transition cylinder and the amplitude variation cone are integrally formed; a connecting bolt is fixed to the upper surface of the first transition cylinder away from the amplitude variation cone, and the bottom of the bolt is provided with an annular protrusion along the vertical axis direction; a bolt hole matching the connecting bolt is provided on the lower surface of the second transition cylinder, and when the first transition cylinder and the second transition cylinder are installed by the connecting bolt, an annular groove is formed between the first transition cylinder and the second transition cylinder; an annular piezoelectric piece matching the shape of the annular groove is installed in the annular groove; a load-bearing bolt for installing an ultrasonic component is fixed to the upper surface of the second transition cylinder; The adjusting section is coaxially fixed to the amplitude changing section by the load-bearing bolts; a plurality of adjusting grooves are provided on the lower surface of the adjusting section, and each adjusting groove contains an electro-hydraulic adjusting member and at least one counterweight ball; The ultrasonic electric spindle also includes a control unit and a power supply unit for providing energy to the ultrasonic components and the electro-hydraulic adjustment member; the control unit collects the electrical signal generated on the annular piezoelectric piece and analyzes the axial force exerted on the tool; the control unit is configured to: when the analysis shows that the axial force exerted on the tool exceeds a predetermined range, control the electro-hydraulic adjustment member to be electrically conductive, thereby changing the position of the counterweight ball in the adjustment slot.

2. The ultrasonic processing equipment for high-hardness and brittle materials according to claim 1, characterized in that: The ultrasonic component is sleeved on the load-bearing bolt, and the ultrasonic component is a plurality of piezoelectric ceramics and a plurality of electrode sheets stacked alternately.

3. The ultrasonic processing equipment for high-hardness and brittle materials according to claim 1, characterized in that: The electro-adjustable component includes a conductive layer, a dielectric layer, and a conductive layer in sequence. The two conductive layers are electrically connected to the power supply part respectively. The dielectric layer expands after being energized, thereby causing the electro-adjustable component to expand and stretch, thereby supporting the counterweight ball to move a certain distance in the adjustment groove.

4. The ultrasonic processing equipment for high-hardness and brittle materials according to claim 3, characterized in that: The plurality of adjustment grooves are radially arranged and centrally symmetrically arranged on the lower surface of the adjustment section.

5. The ultrasonic processing equipment for high-hardness and brittle materials according to any one of claims 1 to 4, characterized in that: The load-bearing bolts are separated from the ultrasonic component by an insulating sleeve.

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