Adaptive flexible machining method and device thereof

Abstract

The present application relates to the technical field of precision machining, and provides a flexible machining method and device with self-adaptive surface shape, wherein the machining method drives the movement of abrasive particles arranged in a magnetic field space and / or the movement of a workpiece to be machined, so that the abrasive particles arranged in the magnetic field space and the workpiece to be machined are in contact and move relatively, thereby machining the workpiece to be machined into a target shape, wherein the causes of the movement of the abrasive particles include the movement of the magnetic field space and / or the vibration of the abrasive particles caused by the magnetic field. The magnetic abrasive particles in the present application have the characteristics of flexible self-adaptive surface shape, and the requirements for the rotation accuracy of the main shaft and the vibration accuracy of the table are greatly reduced during the precision machining process. Meanwhile, the front-end precision matching grinding tool is no longer needed, and the machining method in the present application belongs to weak contact machining, and no temperature rise deformation occurs during the grinding process, so that the whole machining device has a simple structure and the machining cost is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of precision machining technology, and more specifically, to a flexible machining method and apparatus for adaptive surface profiles. Background Technology

[0002] Traditional grinding machines, used for precision grinding of external diameters or internal holes, place extremely high demands on the spindle rotation accuracy, table amplitude, and the precision of the front-end abrasive tool. Furthermore, different sized abrasive tools are required for workpieces with varying outer or inner diameters, making precision machining conditions even more demanding. In addition, this rigid-contact grinding process generates a significant amount of heat, necessitating the use of grinding fluid and coolant for cooling, resulting in a complex and costly overall machining equipment structure. Summary of the Invention

[0003] In view of the deficiencies in the prior art, the purpose of this invention is to provide a flexible processing method and apparatus for adaptive surface shapes.

[0004] According to the present invention, a flexible machining method for adaptive surface profiles is provided, in which abrasive grains arranged in a magnetic field space are driven to move and / or a workpiece is driven to move, so that the abrasive grains arranged in the magnetic field space and the workpiece come into contact and move relative to each other, thereby machining the workpiece into a target shape. The causes of the abrasive grain movement include the movement of the magnetic field space and / or the movement of the abrasive grains due to the magnetic field.

[0005] Preferably, the magnetic field in the magnetic field space includes a superimposed magnetic field formed by any one or more of the following magnetic fields:

[0006] Alternating electromagnetic field;

[0007] The magnetic field generated by a permanent magnet;

[0008] DC electromagnetic field.

[0009] Preferably, the abrasive grains include a variety of abrasive grains with different particle sizes. By adjusting the frequency of the alternating current of the alternating electromagnetic field, one particle size among the various abrasive grains can be driven as the main moving abrasive grain in relative motion to achieve the grinding target.

[0010] Preferably, the timing and intensity of grinding abrasive particles of different sizes can be changed by adjusting the alternating current frequency of the alternating electromagnetic field.

[0011] Preferably, the natural frequency of the main moving abrasive grains is the same as or a harmonic of the frequency of the alternating current of the alternating electromagnetic field.

[0012] Preferably, the abrasive grains are arranged along the magnetic field lines in the magnetic field space. By increasing the intervention magnetic field, the shape of the magnetic field lines can be changed, thereby enabling the processing of a point, line, or surface on the workpiece.

[0013] According to the present invention, an adaptive surface flexible processing apparatus is used to process the workpiece using the adaptive surface flexible processing method, comprising:

[0014] Support structure, used to bear loads;

[0015] A magnetic field body is mounted on the support body, has a magnetic field space, and arranges the abrasive grains in the magnetic field space along the direction of the magnetic field lines; grinding and / or finishing are achieved by driving the abrasive grains to move and / or driving the workpiece to move, so that the workpiece and the abrasive grains move relative to each other.

[0016] Preferably, the device further includes a clamping fixture capable of clamping the workpiece and driving the workpiece to rotate about an axis and / or move along an axial direction, wherein the movement of the workpiece includes six or fewer dimensional directions.

[0017] Preferably, the magnetic field body is an electromagnet and / or a permanent magnet.

[0018] Preferably, the movement of the magnetic field space is achieved by driving the magnetic field body.

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

[0020] 1. The magnetic abrasive grains in this invention possess flexible, adaptive surface characteristics, significantly reducing the precision requirements for spindle rotation and table vibration during precision machining. Furthermore, it eliminates the need for a precision-matched abrasive tool at the front end. Moreover, the machining method in this invention is a weak-contact process, preventing temperature rise and deformation during grinding, thus simplifying the entire machining device structure and greatly reducing processing costs.

[0021] 2. This invention uses abrasive grains of various sizes, each with a different mass and therefore a different resonant frequency. Thus, the magnetic field loading frequency can be targeted according to each resonant frequency, and abrasive grains of different sizes can be controlled as the main moving abrasive grains for finishing. This is beneficial for ultra-precision grinding of the workpiece surface and improves the processing quality. Attached Figure Description

[0022] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0023] Figure 1 This is a schematic diagram of the structure of a two-dimensional magnetic field body in this invention;

[0024] Figure 2 This is a schematic diagram of the structure of a three-dimensional magnetic field body in this invention;

[0025] Figure 3 This is a schematic diagram of the structure when the abrasive particles are arranged in a straight line along the magnetic field lines.

[0026] Figure 4 This is a schematic diagram of the structure when abrasive particles are arranged in a zigzag curve on magnetic field lines;

[0027] Figure 5 This is a schematic diagram showing the abrasive particles arranged in a fan shape along the magnetic field lines.

[0028] Figure 6 Schematic diagrams of the structures of three different abrasive grains;

[0029] Figure 7 This is a schematic diagram of the structure of a one-dimensional Helmholtz coil in this invention;

[0030] Figure 8 This is a schematic diagram of the structure of the two-dimensional Helmholtz coil in this invention;

[0031] Figure 9 This is a schematic diagram of the structure of the three-dimensional Helmholtz coil in this invention;

[0032] Figure 10 This is a schematic diagram of another three-dimensional magnetic field body in this invention;

[0033] Figure 11 A schematic diagram for matching magnetic field lines to a bend in a pipe;

[0034] Figure 12 A schematic diagram of the structure when an interfering magnetic field is applied to a bent pipe to change the magnetic field lines and create a point of convergence of magnetic field lines;

[0035] Figure 13 A schematic diagram of the structure used in machining hole-type parts when a magnetic field rotates and vibrates.

[0036] Figure 14 For hole-type workpieces Figure 13 A schematic diagram of the magnetic field lines during the processing of the device in the diagram;

[0037] Figure 15 A schematic diagram of the structure for machining shaft parts when a magnetic field causes rotation and vibration.

[0038] Figure 16 For shaft-type workpieces Figure 15 A schematic diagram of the magnetic field lines during the processing of the device in the diagram;

[0039] Figure 17 This is a schematic diagram of the structure of a shaft-type part being machined when the workpiece rotates and vibrates under the clamping of a clamping fixture.

[0040] Figure 18 Magnetic field lines and Figure 18The magnetic field lines are in the opposite direction, and the rest of the structure is the same as... Figure 17 The same in;

[0041] Figure 19 This is a schematic diagram of the time-domain signal of an electromagnetic field.

[0042] Figure 20 This is a schematic diagram showing three different masses of abrasive grains subjected to alternating electromagnetic fields of different frequencies.

[0043] Figure 21 This is a schematic diagram of a small magnetic workpiece processing device.

[0044] Figure 22 for Figure 21 A schematic diagram of the workpiece and abrasive grains under the application of alternating electromagnetic fields of different frequencies.

[0045] The diagram shows:

[0046] Workpiece 1

[0047] Magnetic field body 2

[0048] yoke 21

[0049] Coil 22

[0050] Magnetic field space 23

[0051] Clamping fixture 3

[0052] Processing Warehouse 4

[0053] Abrasive 5

[0054] Support 6 Detailed Implementation

[0055] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0056] This invention provides a flexible machining method for adaptive surface profiles. By driving the abrasive particles 5 within the magnetic field space 23 to move and / or driving the workpiece 1 to move, the abrasive particles 5 and the workpiece 1 arranged within the magnetic field space 23 come into contact and undergo relative motion, thereby exhibiting grinding, scraping, and engraving effects. This allows part or all of the workpiece 1 to be machined into the target shape. The movement of the abrasive particles 5 within the magnetic field space 23 includes the movement of the abrasive particles 5 due to the overall movement of the magnetic field body 2 that generates the magnetic field, as well as the vibration of the abrasive particles 5 due to the magnetic field body 2 being an alternating electromagnetic field. The movement of the workpiece 1 includes its own rotation and vibration. The magnetic field in the magnetic field space 23 of this invention can be applied in various ways, such as using any one or more of the following: an alternating electromagnetic field, a magnetic field generated by a permanent magnet, or a DC electromagnetic field, superimposed to form a magnetic field.

[0057] The abrasive grain 5 is preferably a magnetic abrasive grain, and the abrasive grain 5 includes a variety of abrasive grains 5 with different particle sizes, for example, such as Figure 6 As shown, three different abrasive grains have different masses and natural frequencies. Therefore, by adjusting the alternating current frequency of the alternating electromagnetic field, abrasive grains 5 of a certain grain size can achieve the same frequency or a harmonic frequency. After applying the alternating electromagnetic field, abrasive grains 5 with the same or harmonic frequency as the alternating current will resonate with the magnetic field in the magnetic field space 23. This method allows for vibration control of abrasive grains 5 of corresponding grain sizes, enabling targeted selection of abrasive grains 5 to vibrate and grind the workpiece 1, achieving coarse or fine grinding. Therefore, this invention can control the grinding process of abrasive grains 5 of corresponding grain sizes by adjusting the alternating current frequency of the alternating electromagnetic field, thereby meeting the grinding needs of different scenarios. For example, first controlling large-diameter abrasive grains 5 for coarse grinding, and then controlling small-diameter abrasive grains 5 for fine grinding. This invention can change the timing and intensity of grinding of the workpiece 1 by abrasive grains 5 of different grain sizes by changing the alternating current frequency of the alternating electromagnetic field.

[0058] In the specific grinding process, an alternating electromagnetic field can control abrasive grains 5 of one size as the main moving abrasive grain 5, or use a composite alternating electromagnetic field to induce abrasive grains 5 of several sizes as the main moving abrasive grains 5 with relative motion to obtain different grinding targets. In the processing, a mixture of abrasive grains 5 of multiple sizes can be used. By using a composite magnetic field to excite the frequency, abrasive grains 5 of different sizes can also generate harmonic response vibrations in the direction of magnetic field lines, thereby increasing the composite effect of processing multiple particles together.

[0059] In practical applications, each tiny abrasive grain 5 is equivalent to a tiny multi-edged cutting tool. Each abrasive grain 5 scrapes and grinds the surface of the workpiece 1, achieving extremely small amount of material removal. Thousands upon thousands of abrasive grains 5 act on the surface of the workpiece 1, and the grinding effect is the result of the combined action of multiple abrasive grains 5. Magnetic abrasive grains 5 are controlled by a magnetic field, moving along the direction of the magnetic field or arranging themselves according to magnetic field lines, such as... Figure 3 , Figure 4 , Figure 5 As shown, in locations with strong spatial magnetic fields and dense magnetic field lines, abrasive particles 5 converge more, resulting in high grinding pressure, high material removal rate, and strong grinding ability.

[0060] This invention also provides an adaptive surface flexible processing device, which uses an adaptive surface flexible processing method to process a workpiece 1. The device includes a support body 6 and a magnetic field body 2. The support body 6 is used for support, and the magnetic field body 2 is mounted on the support body 6. The magnetic field body 2 has a magnetic field space 23, which allows abrasive grains 5 to be arranged along the direction of magnetic lines of force within the magnetic field space 23. The magnetic field body 2 drives the abrasive grains 5 to move and / or drives the workpiece 1 to move, causing relative movement between the abrasive grains 5 and the workpiece 1, achieving grinding, scraping, and engraving effects. The magnetic field body 2 is an electromagnet and / or a permanent magnet. The electromagnet can be a magnetic field body 2 constructed using a DC electromagnetic coil or an alternating current electromagnetic coil. When an alternating current electromagnetic coil is used to construct the magnetic field body 2, the frequency of the alternating current can be controlled to cause the abrasive grains 5 to vibrate, thereby achieving the grinding operation on the workpiece 1.

[0061] Specifically, various structures can be designed in the construction of the magnetic field to meet the processing needs of different workpieces, such as... Figure 1 , Figure 2 Two-dimensional and three-dimensional magnetic fields were constructed respectively. In practical applications, Helmholtz coils can also be used to construct spatial magnetic fields to meet processing requirements. Figure 1 As shown, the magnetic field body 1 constructs a two-dimensional magnetic field, including a yoke 21, a coil 22 arranged inside the yoke 21, and a magnetic field space 23 formed by the yoke 21 and the coil 22. During the processing, all or part of the abrasive grains 5 and the workpiece 1 are arranged in the magnetic field space 23. By controlling the movement of the abrasive grains 5 and / or the movement of the workpiece 1, the grinding and finishing processing of the workpiece 1 is achieved.

[0062] Specifically, the different loading intensities of the three Helmholtz coils in different directions allow control over the convergence point of the magnetic link path vectors in those three directions, thereby controlling the position of the convergence point, i.e., the concentration point or surface of the magnetic abrasive particles 5. This enables directional and point-controlled machining, such as one-dimensional, two-dimensional, and three-dimensional Helmholtz coils. Figure 7 , Figure 8 , Figure 9As shown, the design can also be tailored to the specific location, precision, and efficiency requirements of the workpiece 1 to be ground. The magnetic field body 2 enables composite control of the spatial magnetic flux vector and intensity, allowing the magnetic lines of force, i.e., the magnetic particle chains with abrasive grains 5, to converge controllably in space. This achieves precise adaptive non-rigid contact machining of the ends of contact points, lines, surfaces, or bodies at program-controlled specified points, lines, or surfaces, or at specified cavities, irregular surfaces, or contour structures.

[0063] like Figure 11 As shown, the magnetic field body 2 constructs a magnetic field that matches the bent tube, with the magnetic field lines in the same direction as the bending direction of the tube. Abrasive particles 5 are arranged along the magnetic field lines. By controlling the relative movement of the abrasive particles 5 and the bent tube, the inner wall of the bent tube is smoothed. The shape of the magnetic field lines can also be changed by increasing the intervention magnetic field, thereby achieving the processing of a specific point, line, or surface on the workpiece 1, such as... Figure 12 As shown, by applying an intervention magnetic field, the magnetic lines of force are changed to create a magnetic convergence point, which in turn allows the abrasive particles 5 to converge at this point. When the bent tube and the abrasive particles 5 move relative to each other, the inner wall of the bent tube at the magnetic convergence point will be ground.

[0064] For workpiece 1 of hole-type parts, the adaptive surface grinding and finishing using magnetic abrasive grains 5 mainly includes the following two basic forms: one is that magnetic abrasive grains 5 are attached to the spindle of an electromagnetic or permanent magnet magnetic field body 2. The rotational vibration of the electromagnetic or permanent magnet drives the magnetic grains to rotate, thereby achieving grinding and finishing of the inner hole. Figure 13 , Figure 14 As shown. Another type uses an external magnetic field 2 to create a rotating and vibrating magnetic field on the inner wall of the hole. The magnetic field drives the magnetic abrasive grains 5 to perform grinding and finishing. The grinding trajectory is diverse and changes with the magnetic field, and the grinding trajectory can be controlled. Shaft parts also include the above two forms, such as... Figure 15 , Figure 16 As shown.

[0065] In one possible embodiment, the adaptive surface flexible machining device further includes a clamping fixture 3, which can clamp the workpiece 1 and drive the workpiece 1 to rotate about its axis and / or move along its axial direction. This includes movement in six or fewer dimensions of the workpiece 1. In practical applications, when the workpiece 1 is a shaft or similar part, it undergoes high-speed rotation and high-frequency vibration under the clamping of the clamping fixture 3. The magnetic abrasive particles 5 vibrate with the alternating magnetic field under the control of the alternating magnetic field. Figure 17 , Figure 18As shown, the magnetic field control includes alternating frequency and magnetic field strength control. The workpiece 1 is submerged in magnetic abrasive grains 5, which grind, scrape, and carve the surface of the workpiece 1 to complete the finishing process. This case involves a combined loading of the mechanical energy of the workpiece 1's rotational vibration and the magnetic energy of the magnetic field. The mechanical energy and magnetic energy can be transformed in various forms and combined in multiple ways according to the actual processing requirements. To maximize energy, the alternating frequency of the magnetic field is selected to be the same as the natural frequency or resonant frequency of the abrasive grains 5. In this case, the change in the magnetic field will excite the resonance of the abrasive grains 5, significantly increasing the amplitude of the abrasive grains 5, further enhancing the energy, and further improving the grinding and finishing efficiency.

[0066] During processing, it is preferable to simultaneously place abrasive grains 5 of various sizes. Each type of abrasive grain 5 has a different mass and a different resonant frequency. Therefore, the magnetic field loading frequency can be targeted according to each resonant frequency. For example, f1 is the resonant frequency of the large abrasive grain 5, f2 is the resonant frequency of the medium abrasive grain 5, and f3 is the resonant frequency of the small abrasive grain 5. In terms of the magnetic field loading method, we can load them sequentially. First, the electromagnetic field harmonic of frequency f1 is loaded, and the intensity is set according to the actual situation. At this time, the large abrasive grain 5 is excited to resonate. The large abrasive grain 5 has a large amplitude and high grinding pressure, and plays a major role in the grinding process, performing coarse grinding on the surface of the workpiece 1. Then, the electromagnetic field harmonic of frequency f2 is loaded. At this time, the medium abrasive grain 5 plays a major role in the grinding process, performing fine grinding on the surface of the workpiece 1. Finally, the electromagnetic field harmonic of frequency f3 is loaded. At this time, the small abrasive grain 5 plays a major role in the grinding process, performing ultra-fine grinding on the surface of the workpiece 1.

[0067] Furthermore, electromagnetic field loading can also simultaneously contain the above three frequency components, and its time-domain spectrum is as follows: Figure 19 Electromagnetic field spectrum curve Figure 20 As shown, under the excitation of this signal, the large, medium and small abrasive particles 5 vibrate at their own resonant frequencies, and complete the rough, fine and ultra-fine grinding and finishing processes together.

[0068] For magnetic workpiece 1 or magnetically conductive workpiece 1, the following can be used: Figure 21 The processing apparatus shown performs grinding and finishing. The processing chamber 4 contains a suitable amount of magnetic abrasive grains 5. The workpiece 1 is also placed inside the processing chamber 4, submerged in the magnetic abrasive grains 5. The workpiece 1 and the magnetic abrasive grains 5 have different resonant frequencies. The electromagnetic field signal applied by the magnetic field body 2 simultaneously contains the resonant frequency of both the workpiece 1 and the magnetic abrasive grains 5. Under the excitation of the external magnetic field, the workpiece 1 and the magnetic abrasive grains 5 will vibrate violently at their respective resonant frequencies. Because their vibration frequencies and amplitudes are different, such as... Figure 22 As shown, there will be intense relative motion between the workpiece 1 and the magnetic abrasive grains 5. The magnetic abrasive grains 5 will collide, scrape and engrave the surface of the workpiece, and complete the grinding and finishing process of the workpiece.

[0069] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0070] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A flexible processing method for adaptive surface shapes, characterized in that, By driving the abrasive grains (5) arranged in the magnetic field space (23) to move and / or driving the workpiece (1) to move, the abrasive grains (5) arranged in the magnetic field space (23) and the workpiece (1) to move, the workpiece (1) is processed into a target shape by contacting and relative movement between them, wherein the causes of movement of the abrasive grains (5) include movement of the magnetic field space (23) and / or movement of the abrasive grains (5) due to the magnetic field; By placing abrasive grains (5) of various sizes in the magnetic field space (23), each abrasive grain (5) has a different mass and therefore a different resonant frequency. At the magnetic field loading frequency, the abrasive grains (5) of different sizes can be loaded in a targeted manner according to each resonant frequency, and then the abrasive grains (5) of different sizes can be controlled as the main moving abrasive grains (5) to perform finishing, thereby realizing ultra-precision grinding of the surface of the workpiece (1). The flexible machining method for adaptive surface profiles is a weak contact machining method, and no temperature rise deformation will occur during the grinding process.

2. The flexible fabrication method for adaptive surface profiles according to claim 1, characterized in that, The magnetic field in the magnetic field space (23) includes a superimposed magnetic field formed by any one or more of the following magnetic fields: Alternating electromagnetic field; The magnetic field generated by a permanent magnet; DC electromagnetic field.

3. The flexible fabrication method for adaptive surface profiles according to claim 2, characterized in that, The abrasive grains (5) include a variety of abrasive grains (5) with different particle sizes. By adjusting the frequency of the alternating current of the alternating electromagnetic field, abrasive grains (5) of one particle size among the various particle sizes can be driven as the main moving abrasive grains (5) in relative motion to achieve the grinding target.

4. The flexible fabrication method for adaptive surface profiles according to claim 3, characterized in that, By adjusting the frequency of the alternating current in the alternating electromagnetic field, the timing and intensity of grinding with abrasive particles of different sizes (5) can be changed.

5. The flexible fabrication method for adaptive surface shapes according to claim 3, characterized in that, The natural frequency of the main moving abrasive grain (5) is the same as or a multiple of the frequency of the alternating current of the alternating electromagnetic field.

6. The flexible fabrication method for adaptive surface profiles according to claim 2, characterized in that, The abrasive grains (5) are arranged along the magnetic lines of force in the magnetic field space (23). By increasing the intervention magnetic field, the shape of the magnetic lines of force can be changed, thereby enabling the processing of a point, line or surface on the workpiece (1).

7. A flexible processing device for adaptive surface shape, characterized in that, The workpiece (1) is processed using the adaptive surface flexible processing method according to any one of claims 1 to 6, comprising: Support (6) is used for bearing load; A magnetic field body (2) is mounted on the support body (6) and has a magnetic field space (23) so that the abrasive grains (5) can be arranged in the direction of the magnetic field lines in the magnetic field space (23); grinding and / or finishing are achieved by driving the abrasive grains (5) to move and / or driving the workpiece (1) to move so that the workpiece (1) and the abrasive grains (5) move relative to each other.

8. The flexible processing apparatus for adaptive surface profiles according to claim 7, characterized in that, It also includes a clamping fixture (3), which is capable of clamping the workpiece (1) and driving the workpiece (1) to rotate about the axis and / or move along the axial direction, including the movement of the workpiece (1) in 6 or less dimensional directions.

9. The flexible processing device for adaptive surface shape according to claim 7, characterized in that, The magnetic field body (2) is an electromagnet and / or a permanent magnet.

10. The flexible processing apparatus for adaptive surface profiles according to claim 7, characterized in that, The movement of the magnetic field space (23) is achieved by driving the magnetic field body (2).

Images