Fixture for magnetic mirror milling based on electromagnetic semi-active local support

Abstract

The present invention discloses a fixture for magnetic mirror milling based on electromagnetic semi-active local support, comprising an active side integrated plate and a follower side integrated plate. The follower side integrated plate is provided with an electromagnetic semi-active local support device, the electromagnetic semi-active local support device comprising a fixed component and a movable component inserted into the fixed component; the movable component comprises a wave mechanical spring and an annular magnet, and an annular coil structure is sheathed on the annular magnet; the electromagnetic semi-active local support device is rigidly connected to the follower side integrated plate by two screws; three strong magnetic switches and three ball bearings are evenly arranged circumferentially between the follower side integrated plate and the active side integrated plate; the active side integrated plate is mounted on the spindle of a milling robot. The fixture of the present invention provides out-of-plane support for local milling points of thin-walled workpieces from the perspective of electromagnetic structure design and practical application. The device has the advantages of simple structure, fast response, linear modulation, and a large adjustable range.

Description

Technical Field

[0001] The present invention relates to a chatter suppression technology for thin-wall workpiece milling, which can be applied to magnetic follow-up mirror milling technology, and in particular to an electromagnetic semi-active adjustable integrated follow-up support milling device. Background Art

[0002] Thin-walled structures, such as aircraft skins, are crucial components of large-scale equipment in aerospace and other fields. These structures, such as aircraft skins, withstand and transmit aerodynamic loads with their lightweight and high structural strength. Equipment upgrades are essential for improving the performance of key components. The growing demand for thin-walled workpieces requires innovation and advancement in manufacturing technologies to achieve high-quality, reliable, efficient, and environmentally friendly machining. These structures are characterized by their thinness, large size, and high material removal rates during machining. The low out-of-plane stiffness resulting from their thin walls frequently leads to chatter during machining, severely impacting workpiece quality and efficiency, and even accelerating the damage of machining equipment. Furthermore, machining involves numerous complex dynamic issues, such as the variation of milling system parameters with machining position and time. Targeting these weakly rigid workpieces, the magnetic follow-up mirror milling technology utilizes magnetic force to attach a fixture to both sides of the workpiece, providing real-time rigid support for the workpiece as it follows the milling cutter during machining. Providing adjustable support force at the milling point to accommodate different machining positions, further supplement the workpiece's local stiffness, and mitigate the effects of time-varying characteristics is crucial for improving the machining quality of thin-walled workpieces. Summary of the Invention

[0003] In response to the above-mentioned existing technologies, the present invention provides a fixture for magnetic mirror milling based on electromagnetic semi-active local support. By focusing on the design and practical application of electromagnetic structures, this device provides local out-of-plane support at the milling point of thin-walled workpieces. This device offers advantages such as simple structure, fast response, linear modulation, and a wide adjustable range.

[0004] In order to solve the above technical problems, the present invention proposes a fixture for magnetic mirror milling based on electromagnetic semi-active local support, which includes an active side integrated plate and a follower side integrated plate. The follower side integrated plate is provided with an electromagnetic semi-active local support device, and the electromagnetic semi-active local support device includes a fixed component and a movable component inserted into the fixed component; the fixed component includes a shell, the bottom plate of the shell is provided with a lower groove, the bottom of the lower groove is provided with a shell center hole, the top of the shell is embedded with a top cover, and the top of the top cover is provided with a protrusion , the bottom of the top cover is provided with an upper groove, and the top cover is provided with a top cover center hole coaxial with the center hole of the shell; a lower lubricating sleeve is installed in the center hole of the shell, and a gap gasket is provided in the lower groove; an upper lubricating sleeve is installed in the center hole of the top cover; the movable component includes a central shaft, the central shaft is a stepped shaft with a large diameter shaft section at the bottom, the upper part of the central shaft is a screw, the top of the screw is provided with a central threaded hole, the central threaded hole is connected to a push rod, the top of the push rod is connected to a push rod head gasket, and the upper surface of the push rod head gasket is evenly distributed with a plurality of protrusions;

[0005] The central shaft passes through the lower lubricating sleeve to the upper lubricating sleeve, the large-diameter shaft section at the lower end of the central shaft is covered with a wave mechanical spring, the small-diameter shaft section of the central shaft is covered with a three-layer annular magnet, the upper end of the wave mechanical spring contacts the bottom surface of the three-layer annular magnet, the lower end of the wave mechanical spring contacts the bottom surface of the lower groove of the shell bottom plate, the three-layer annular magnet is covered with an annular coil structure fixed to the shell, the screw on the upper part of the central shaft is connected to a hexagonal nut, the hexagonal nut fixes the three-layer annular magnet on the central shaft, and there is no gap between adjacent layers of annular magnets. Under the action of the wave mechanical spring, the top of the three-layer annular magnet is higher than the top of the annular coil structure;

[0006] The annular coil structure is composed of three annular coils of the same specifications. The three annular coils are arranged in sequence from top to bottom and are sequentially recorded as the first annular coil, the second annular coil, and the third annular coil. When the coils are energized, the magnetic poles remain opposite to the magnetic poles of the annular magnet. The inner leads of the three annular coils are in the same direction. The inner leads of the first annular coil and the inner leads of the third annular coil are connected to the two poles of the DC power supply. The outer lead of the first annular coil is connected to the inner lead of the second annular coil, and the outer lead of the second annular coil is connected to the outer lead of the third annular coil.

[0007] Two screw counterbores are provided at the edge of the bottom surface of the top cover, screws are preset in the screw counterbores, and the screw shafts of the screws pass through the screw counterbores and are exposed above the top cover; threaded holes are provided on the follower side integrated plate at positions corresponding to the two screws, and the electromagnetic semi-active local support device is rigidly connected to the follower side integrated plate through the two screws;

[0008] The outer shell is provided with N radial through holes evenly distributed in the circumferential direction at the position where the outer shell is embedded and in contact with the top cover. The top cover is provided with a threaded hole coaxial with each radial through hole, and the top cover and the outer shell are rigidly connected by threaded connection.

[0009] The active side integrated board is installed on the spindle of the milling robot, and the follower side integrated board and the active side integrated board are provided with three strong magnetic switches with corresponding positions and flush heights at the peripheral outer edges of the relative surfaces of the two; the follower side integrated board and the active side integrated board are both provided with three balls with corresponding positions and flush heights on the relative surfaces of the two, and the height of the balls on the same side integrated board protrudes beyond the height of the strong magnetic switches.

[0010] Furthermore, the fixture for magnetic mirror milling of the present invention, wherein:

[0011] The lower lubricating sleeve and the center hole of the shell are in interference fit, and the bottom ends of the two are flush; the upper lubricating sleeve and the center hole of the top cover are in interference fit.

[0012] Four rectangular holes are evenly distributed along the circumference on the side wall of the shell to reduce the structural mass and facilitate heat dissipation of the coil.

[0013] The upper end of the wave mechanical spring is higher than the shoulder position of the large-diameter shaft section of the central shaft.

[0014] The original length of the wave mechanical spring is L1, the depth of the lower groove of the shell is L2, the depth of the upper groove of the top cover is L3, the height of each layer of annular magnets is H1, and the height of the hexagonal nut is H2; L1-L2=H1, L3>H1, L3>H2; the thickness of the gap gasket is adjustable, the movable component is raised by the wave mechanical spring, the hexagonal nut is located in the upper groove of the top cover, and the distance between the top of the first layer of annular magnets on the top and the top surface of the top cover is equal to d2; after the active side integrated board and the follower side integrated board are adsorbed, the wave mechanical spring is compressed, and the compression amount is equal to the height of the gap gasket.

[0015] The ejector head gasket is coaxial with the milling cutter and is located on both sides of the workpiece.

[0016] The heights of the balls on the integrated boards on the same side are consistent, and the heights of the strong magnetic switches on the integrated boards on the same side are consistent.

[0017] The connection between the push rod head gasket and the push rod is glue bonding.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention utilizes Ampere's law to achieve adjustable and rapid response of the supporting force without involving complex feedback circuits; the magnitude of the supporting force can be linearly modulated in real time by adjusting the magnitude and direction of the current in the coil;

[0020] The present invention adopts a multi-layer coil series connection method, which simplifies the connection and arrangement of the coils. It only needs to adjust the connection sequence between the coils to generate magnetic fields in different directions, and only one input end and one output end are required.

[0021] The present invention adopts a multi-layer electromagnetic structure instead of a simple single-layer arrangement, rationally sets the magnetic pole direction and relative height of the multi-layer magnet and coil structure, and produces a large adjustable range while maintaining a compact structure.

[0022] The present invention utilizes the pre-compression of a mechanical spring to apply a certain supporting force to the thin-walled workpiece through a movable component, and can still maintain a certain supporting effect when the adjustable electromagnetic structure fails;

[0023] The present invention has two adjustment modes: the pre-compression force of the wave mechanical spring is used to adjust the center value of the target support force range, and the electromagnetic force applied by the energized coil to the magnet is further adjusted based on the pre-compression force, which can produce a large adjustment range and is suitable for various processing conditions;

[0024] The present invention takes into account the friction between the ejector head gasket and the workpiece, and adopts convex point contact instead of surface contact, thereby reducing friction, providing support force and protecting the workpiece at the same time;

[0025] The present invention adopts an integrated installation method. When it is used, there is no need to change the original device. It is only necessary to connect the structure to the threaded hole reserved on the follower integrated board through bolts.

[0026] The present invention has the advantages of convenient and quick structural assembly, low cost, small size, light weight, and significant effect of suppressing the chatter of thin-walled workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the structure of the electromagnetic semi-active adjustable support device in the fixture for magnetic mirror milling of the present invention;

[0028] Figure 2 for Figure 1 A cross-sectional view of the electromagnetic semi-active adjustable support device in the adsorption state;

[0029] Figure 3 for Figure 2 A cross-sectional schematic diagram of the fixing assembly 1 is shown in FIG;

[0030] Figure 4 for Figure 2 Schematic diagram of movable component 2 shown in;

[0031] Figure 5 for Figure 2 The arrangement diagram of the annular coil structure and the annular magnet shown in;

[0032] Figure 6 A schematic diagram of a magnetic follower device and a milling cutter used in conjunction with the device of the present invention;

[0033] Figure 7 Schematic diagram of the decomposition of the active and follower integrated plates in the fixture of the present invention;

[0034] Figure 8-1 Schematic diagram of the structure of the follower side of the clamp of the present invention;

[0035] Figure 8-2 for Figure 8-1 A structural diagram of another perspective of the follower side is shown;

[0036] Figure 9 A comparison of the electromagnetic forces generated by the annular coil structure and annular magnet arrangement in the present invention and other arrangements under the same current;

[0037] Figure 10 This is a graph showing how the supporting force provided by the fixture of the present invention to the workpiece changes with current under different pre-compression amounts.

[0038] In the picture:

[0039] 1-Fixed component 11-Hollow top cover 12-Outer shell

[0040] 13-upper lubrication sleeve 14-lower lubrication sleeve 15-annular coil structure

[0041] 151 - first toroidal coil 152 - second toroidal coil 153 - third toroidal coil

[0042] 16-Gap spacer 2-Movable component 21-Magnet

[0043] 22-Center shaft 23-Push rod 24-Push rod head gasket

[0044] 25-Hexagonal nut 26-Wave mechanical spring 31-Strong magnetic switch

[0045] 32-ball 331-active side integrated plate 332-following side integrated plate

[0046] 34- milling cutter 35- workpiece DETAILED DESCRIPTION

[0047] In the description of this patent, it should be understood that the terms "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the invention and should not be construed as limiting this patent. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish between multiple identical structures and should not be construed as indicating or implying relative importance or implicitly specifying the number of the indicated technical features.

[0048] In the description of the patent of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be internal communication between two components.

[0049] The present invention proposes a fixture for magnetic mirror milling based on electromagnetic semi-active local support. Its design concept is to provide active and follower integrated boards on both sides of a workpiece 35. The active integrated board is mounted on the spindle of a milling robot, and the follower integrated board is provided with an electromagnetic semi-active local support device consisting of a fixed component and a movable component inserted into the fixed component. The magnitude of the supporting force can be linearly modulated in real time by adjusting the magnitude and direction of the current in the coil. The movable component applies a certain supporting force to the thin-walled workpiece through the pre-compression of a mechanical spring, and can still maintain a certain supporting effect when the adjustable electromagnetic structure fails. The contact with the workpiece uses convex point contact instead of surface contact, thereby reducing friction, providing support force, and protecting the workpiece. The fixture of the present invention provides out-of-plane support for the local milling point of thin-walled workpieces from the perspective of electromagnetic structure design and practical application. The device has the advantages of simple structure, fast response, linear modulation, and a wide adjustable range.

[0050] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the following embodiments are by no means intended to limit the present invention in any way.

[0051] like Figure 6 As shown, the present invention proposes a fixture for magnetic mirror milling based on electromagnetic semi-active local support, including an active side integrated plate 321 and a follower side integrated plate 332, on which an electromagnetic semi-active local support device is provided, such as Figure 1 、 Figure 8-1 and Figure 8-2 shown.

[0052] The electromagnetic semi-active local support device includes a fixed component 1 and a movable component 2 inserted into the fixed component 1. Figure 1 shown.

[0053] The fixing assembly 1 includes a shell 12, the bottom plate of the shell 12 is provided with a lower groove, the bottom of the lower groove is provided with a shell center hole, and the side wall of the shell 12 is evenly distributed along the circumference to reduce the structural mass and facilitate heat dissipation of the coil. A top cover 11 is embedded in the top of the shell 12, the top of the top cover 11 is provided with a protrusion, the bottom of the top cover 11 is provided with an upper groove, and the top cover 11 is provided with a top cover center hole coaxial with the shell center hole; a lower lubricating sleeve 14 is installed in the shell center hole, and the lower lubricating sleeve 14 and the shell center hole are interference fit, and the bottom ends of the two are flush; a gap gasket 16 is provided in the lower groove, and an upper lubricating sleeve 13 is installed in the top cover center hole, and the upper lubricating sleeve 13 and the top cover center hole are interference fit, as shown in FIG. Figure 1 、 Figure 2 and Figure 3 shown.

[0054] like Figure 1 、 Figure 2 and Figure 4 As shown, the movable component 2 includes a central shaft 22, which is a stepped shaft with a large diameter shaft section at the bottom. The upper part of the central shaft is a screw, and the top of the screw is provided with a central threaded hole. The central threaded hole is connected to a push rod 23, and the top of the push rod 23 is connected to a push rod head gasket 24. The connection between the push rod head gasket 24 and the push rod 23 is glue-bonded. In order to reduce the weight of the structure, a hollow cylindrical structure is adopted at the bottom end of the central shaft 22. The upper surface of the push rod head gasket 24 is evenly distributed with a plurality of protrusions, which replace surface contact with point contact, thereby providing support for the workpiece while reducing friction on the workpiece, thereby protecting the integrity and smoothness of the workpiece surface. The push rod head gasket 24 and the milling cutter 34 are coaxial and located on both sides of the workpiece 35, as shown Figure 6 shown.

[0055] The central shaft 22 passes through the lower lubricating sleeve 14 to the upper lubricating sleeve 13, and a wave mechanical spring 26 is mounted on the large diameter shaft section at the lower end of the central shaft 22, and the upper end of the wave mechanical spring 26 is higher than the shoulder position of the large diameter shaft section of the central shaft 22; the small diameter shaft section of the central shaft 22 is mounted with a three-layer annular magnet 21, and the upper end of the wave mechanical spring 26 contacts the bottom surface of the three-layer annular magnet 21, and the lower end of the wave mechanical spring 26 contacts the bottom surface of the lower groove of the bottom plate of the outer shell 12, and the three-layer annular magnet 21 is sheathed with an annular coil structure 15 fixed to the outer shell 12.

[0056] The screw on the upper part of the central shaft 22 is connected to a hexagonal nut 25, and the three-layer annular magnet 21 adopts an SN-SN-NS pole (or NS-NS-SN pole) arrangement. Figure 5As shown, the annular coil structure 15 is composed of three annular coils of the same specifications. The three annular coils are arranged in sequence from top to bottom and are recorded as the first annular coil 151, the second annular coil 152 and the third annular coil 153. The magnetic poles of the coils after power is applied are opposite to the magnetic poles of the annular magnet 21. The inner leads of the three annular coils are in the same direction. The inner leads of the first annular coil 151 and the inner leads of the third annular coil 153 are connected to the two poles of the DC power supply. The outer leads of the first annular coil 151 are connected to the inner leads of the second annular coil 152, and the outer leads of the second annular coil 152 are connected to the outer leads of the third annular coil 153. The inner leads of the three annular coils are in the same direction. The three-layer annular coils are connected in series end to end, and the magnetic field generated after power is applied is kept consistent. The magnetic field is in the opposite direction to that of the three-layer annular magnet in the movable assembly. The hexagonal nut 25 secures the three-layer annular magnet 21 to the central shaft 22, with no gap between adjacent layers of annular magnets 21. Under the action of the wave mechanical spring 26, the tops of the three-layer annular magnet 21 are elevated above the top of the annular coil structure 15. The upper and lower lubricating bushings are used to connect the central shaft 22 of the movable assembly, ensuring smooth and unstuck movement of the movable assembly. The gap gasket 16 is used to adjust the compression of the wave mechanical spring 26 in the movable assembly. As the ejector head is subjected to force, the movable assembly 2 can move up and down within the center of the fixed assembly 1, supported by the wave mechanical spring 26 and electromagnetic force. The ejector head gasket 24 is designed to directly contact the thin-walled workpiece 35. Under the action of the wave mechanical spring 26, the ejector head gasket 24 maintains close contact with the workpiece 35, thereby compressing the wave mechanical spring 26. The compressive force of the wave mechanical spring 26 and the electromagnetic force generated by the energized coil on the magnet act on the workpiece, providing out-of-plane support and stiffness for the thin-walled workpiece. In order to provide sufficient support for the workpiece, in the present invention, a gap gasket 16 is placed under the wave mechanical spring 26. Under the action of the gap gasket 16, the height of the annular magnet above the annular coil is adjusted to the sum of the height of the gap gasket 16 and the height of the single-layer annular magnet. Figure 9 A comparison of the electromagnetic forces generated by the annular coil structure and annular magnet arrangement of the present invention and other arrangements under the same current is shown; Figure 10 The figure shows the change of the supporting force provided by the clamp of the present invention for the workpiece under different pre-compression amounts as the current changes.

[0057] The annular coil structure 15 is composed of three annular coils of the same specifications. The three annular coils are arranged in sequence from top to bottom and are respectively recorded as the first annular coil 151, the second annular coil 152 and the third annular coil 153. The magnetic poles of the coils after power is applied are opposite to the magnetic poles of the annular magnet 21; the inner leads of the three annular coils are in the same direction, the inner leads of the first annular coil 151 and the inner leads of the third annular coil 153 are connected to the two poles of the DC power supply, the outer lead of the first annular coil 151 is connected to the inner lead of the second annular coil 152, and the outer lead of the second annular coil 152 is connected to the outer lead of the third annular coil 153.

[0058] Two screw countersunk holes are provided at the edge of the bottom surface of the top cover 11, and screws are preset in the screw countersunk holes. The screw rods of the screws pass through the screw countersunk holes and are exposed above the top cover 11 for connection with the magnetic follower clamp; threaded holes are provided on the follower side integrated plate 332 at positions corresponding to the two screws, and the electromagnetic semi-active local support device is rigidly connected to the follower side integrated plate 332 through the two screws.

[0059] The outer shell 12 is provided with six radial through holes evenly distributed in the circumferential direction at the position where it is embedded and in contact with the top cover 11. The top cover 11 is provided with a threaded hole coaxial with each radial through hole. The top cover 11 and the outer shell 12 are rigidly connected by threaded connection; and the annular coil structure 15 is fixed therein.

[0060] The active side integrated board 331 is installed on the main shaft of the milling robot. The follower side integrated board 332 and the active side integrated board 331 are provided with three strong magnetic switches 31 at the peripheral edges of the relative surfaces of the two. The follower side integrated board 332 and the active side integrated board 331 are provided with three balls 32 at multiple positions corresponding to each other and at the same height on their relative surfaces. The heights of the balls 32 on the same side integrated board are consistent. The heights of the strong magnetic switches 31 on the same side integrated board are consistent. The heights of the balls 32 on the same side integrated board are higher than the heights of the strong magnetic switches 31. Figure 7 、 Figure 8-1 and Figure 8-2 As shown,

[0061] In the present invention, the original length of the wave mechanical spring 26 is L1, the depth of the lower groove of the housing 12 is L2, the depth of the upper groove of the top cover 11 is L3, the height of each layer of annular magnets 21 is H1, and the height of the hexagonal nut 25 is H2; L1-L2=H1, L3>H1, L3>H2; the thickness of the gap gasket 16 is adjustable, the movable component 2 is raised by the wave mechanical spring 26, the hexagonal nut 25 is located in the upper groove of the top cover 11, and the distance between the top of the first layer of annular magnets on the top and the top surface of the top cover 11 is equal to d2; after the active side integrated plate 331 and the follower side integrated plate 332 are adsorbed, the wave mechanical spring 26 is compressed, and the compression amount is equal to the height of the gap gasket 16, as shown in FIG. Figure 2 shown.

[0062] In the present invention, the active side is mounted on the milling spindle and moves synchronously with the milling cutter 34; three strong magnetic switches 31 are arranged on the main and follower devices respectively. Under the action of strong magnetic force, the follower side can be adsorbed on the other side of the workpiece 35 and maintain continuous follow-up under the action of the ball 32, such as Figure 6 As shown. The top cover 11 in the fixing component 1 is provided with two threaded holes and two screws are installed upside down for connection to the integrated board 33 on the follower side of the magnetic follower device, so that the fixing component and the follower side of the magnetic follower device are rigidly connected; by utilizing the strong magnetic force generated by the magnetic switch and the rigid connection between the follower side and the fixing component, the movable component can provide supporting force in a large range and keep the overall structure of the follower side from falling off; in the initial position, there is no gap gasket 16, and under the support of the wave mechanical spring 26, the three-layer annular magnet structure is higher than the height of one layer of the three-layer annular coil structure. At this position, the annular magnet structure is subjected to the maximum electromagnetic force and the minimum electromagnetic stiffness, and the head of the ejector pin just keeps in contact with the workpiece but does not The state of being under stress; adjusting the height of the gap gasket 16 further adjusts the relative distance between the movable component and the fixed component in the height direction, that is, the annular magnet is higher than the height of the coil; installing the device on the workpiece, the push rod head gasket 24 contacts the workpiece, the gap gasket 16 raises the movable component 2 so that the wave compression spring 26 is compressed, and the compression amount is the height of the gap gasket 16. At the same time, the annular magnet and the coil restore the relative distance of the initial position, and the movable component 2 is subjected to the compression force of the spring and the electromagnetic force generated by the energized coil. The sum of the two is transmitted to the workpiece through the central axis 22, the push rod 23 and the push rod head gasket 24; the movable component 2 is an axisymmetric geometric shape, and its axis is collinear with the milling cutter on the opposite side.

[0063] The working process of the device of the present invention is as follows:

[0064] When the milling cutter 34 is fed along the preset path, under the adsorption of the strong magnetic switch, the fixed component 1 and the follower side device form a whole, and move synchronously with the milling cutter spindle on the other side of the workpiece 35; the movable component 2 contacts the workpiece through the push rod head gasket 24, so that the wave mechanical spring 26 is compressed, and the compression amount is the height of the gap gasket; the restoring force generated by the compression of the wave mechanical spring acts on the workpiece through the movable component, providing support force for the workpiece on the opposite side of the milling cutter 34, so as to increase the local stiffness at the milling point of the thin-walled workpiece and weaken the vibration problem caused by the weak stiffness of the workpiece; if the support force needs to be adjusted over a large range, the height of the gap gasket can be adjusted; further, the support force increases linearly by increasing the current; the current source is reversed, the current increases, and the support force decreases linearly.

[0065] Example

[0066] A TriMule-600 hybrid robot was used for end milling testing. The cutter had a diameter of 12 mm, a length of 50 mm, three teeth, and a helix angle of 45°. The workpiece was 300 mm long and wide, with a thickness of 3 mm. The workpiece was clamped symmetrically in a vise using cantilevered boundary conditions, with the lower boundary symmetrically clamped in a fixed area 200 mm long and 25 mm wide. The master and slave sides of the magnetic follower support device primarily consisted of an integrated board, connectors, and a magnetic switch. The switch was MagJig-95.

[0067] The dimensions of the device of the present invention are set as follows: the outer diameter of the main body is 60mm, the outer diameter of the upper boss is 22mm, the height is 10mm, the outer diameter of the lower groove is 32mm, the protrusion height is 7mm, and the overall height of the component is 42.5mm.

[0068] The overall structure is arranged in sequence from the outside to the inside, the fixed component 1, including the top cover 11 with an outer diameter of 56mm and a thickness of 8.5mm. The top cover reserves two M5 threaded holes symmetrically arranged on both sides of the boss with a distance of 46mm. The top cover evenly arranges six M3 threaded holes in the thickness direction. The bottom of the top cover has a large groove with a diameter of 36mm and a depth of 6.5mm and a small groove with a diameter of 18mm and a depth of 6mm; the shell 12 is 32.5mm high, and six through holes are arranged radially at a height of 5mm from the upper edge for fastening with the top cover. Four rectangular holes with a length of 28mm and a width of 15mm are evenly distributed radially in the shell; the annular coil is a copper coil with an outer diameter of 57mm, an inner diameter of 31mm, and a single-layer height of 5mm; the upper sleeve has an inner diameter of 10.5mm and a height of 6mm; the lower sleeve has an inner diameter of 14mm and a height of 7mm; the gap gasket has an inner diameter of 16mm, an outer diameter of 24.5mm, and a single-layer height of 0.1mm; the movable component 2, including The center shaft has a diameter of 10mm and a total length of 43mm. The center shaft boss has a diameter of 13.5mm and a length of 14mm. There is a 20mm long M10 thread on the top of the center shaft boss, and an M5 threaded hole with a diameter of 4.2mm and a depth of 5mm on the top of the center shaft. The ring magnet is an N35 neodymium iron boron magnet with an outer diameter of 30mm, an inner diameter of 10mm, and a single layer height of 5mm. The hexagonal nut has a single side length of 8.5mm and an M10 thread in the center. The outer diameter of the main body of the push rod is 10mm. m, total length 13mm, with a 5mm long M5 screw extending from the bottom, and a small platform with a diameter of 20mm and a thickness of 1.5mm on the top; the support head gasket has an outer diameter of 25mm and an overall height of 4.5mm, with seven evenly distributed convex points of 1mm in height on the top, and a groove with a diameter of 20.5mm and a depth of 3mm on the bottom; the wave mechanical spring has an inner diameter of 19.59mm, an outer diameter of 24.37mm, a height of 11.1mm, and a stiffness of 1.61×10 4 N / m.

[0069] The resultant force along the axial direction of the structure applied by the energized coil 15 and the compressed spring 26 to the movable component 2 acts on the thin-walled workpiece through the push rod and maintains a coaxial position with the milling cutter; under the action of the magnetic follower device, the device of the present invention moves synchronously with the milling cutter, providing adjustable support force for the milling point in real time.

[0070] After testing: when the device of the present invention is assembled, fasteners are used to rigidly connect the follower side of the magnetic follower device. It is only necessary to turn on the switch of the magnetic follower device and adsorb the overall structure on the workpiece to provide supporting force for the workpiece; when the device of the present invention is working, by adjusting the height of the gap gasket, the size of the supporting force can be preliminarily determined to provide support for the workpiece at the milling point under different mirror milling processing conditions; further, by adjusting the current size and direction, the size of the supporting force can be finely adjusted to provide linear adjustment, fast response and a wide adjustable range of supporting force for the workpiece milling point to adapt to different milling positions; when the device of the present invention is disassembled, it is only necessary to disconnect the coil power supply, turn off the magnetic switch, and remove the fastening screws. The disassembly process is convenient and quick.

[0071] Although the present invention has been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can make many improvements and changes without departing from the purpose of the present invention, which are all protected by the present invention.

Claims

1. A fixture for magnetic mirror milling based on electromagnetic semi-active local support, comprising an active side integrated plate (331) and a follower side integrated plate (332), wherein the follower side integrated plate (332) is provided with an electromagnetic semi-active local support device, characterized in that: The electromagnetic semi-active local support device comprises a fixed component (1) and a movable component (2) inserted into the fixed component (1); The fixing assembly (1) includes a shell (12), the bottom plate of the shell (12) is provided with a lower groove, the bottom of the lower groove is provided with a shell center hole, the top of the shell (12) is embedded with a top cover (11), the top of the top cover (11) is provided with a protrusion, the bottom of the top cover (11) is provided with an upper groove, and the top cover (11) is provided with a top cover center hole coaxial with the shell center hole; a lower lubricating sleeve (14) is installed in the shell center hole, a gap gasket (16) is provided in the lower groove; an upper lubricating sleeve (13) is installed in the top cover center hole; The movable component (2) includes a central shaft (22), the central shaft (22) is a stepped shaft with a large diameter shaft section at the bottom, the upper part of the central shaft is a screw, the top end of the screw is provided with a central threaded hole, the central threaded hole is connected to a push rod (23), the top of the push rod (23) is connected to a push rod head gasket (24), and the upper surface of the push rod head gasket (24) is uniformly distributed with a plurality of protrusions; The central shaft (22) passes through the lower lubricating sleeve (14) to the upper lubricating sleeve (13); a wave mechanical spring (26) is mounted on the large diameter shaft section at the lower end of the central shaft (22); a three-layer annular magnet (21) is mounted on the small diameter shaft section of the central shaft (22); the upper end of the wave mechanical spring (26) contacts the bottom surface of the three-layer annular magnet (21); the lower end of the wave mechanical spring (26) contacts the bottom surface of the lower groove of the bottom plate of the housing (12); the three The annular magnets (21) are sheathed with an annular coil structure (15) fixed to the housing (12); a screw on the upper portion of the central shaft (22) is connected to a hexagonal nut (25); the hexagonal nut (25) fixes the three-layer annular magnets (21) on the central shaft (22); and there is no gap between adjacent layers of annular magnets (21); under the action of the wave mechanical spring (26), the tops of the three-layer annular magnets (21) are higher than the top of the annular coil structure (15); The annular coil structure (15) is composed of three annular coils of the same specifications. The three annular coils are arranged in sequence from top to bottom and are sequentially recorded as a first annular coil (151), a second annular coil (152) and a third annular coil (153). The magnetic poles of the coils after being energized are opposite to the magnetic poles of the annular magnet (21). The inner leads of the three annular coils have the same direction. The inner leads of the first annular coil (151) and the inner leads of the third annular coil (153) are connected to the two poles of a DC power supply. The outer leads of the first annular coil (151) are connected to the inner leads of the second annular coil (152), and the outer leads of the second annular coil (152) are connected to the outer leads of the third annular coil (153). Two screw countersunk holes are provided at the edge of the bottom surface of the top cover (11), screws are preset in the screw countersunk holes, and the screw rods of the screws pass through the screw countersunk holes and are exposed on the top cover (11); threaded holes are provided on the follower side integrated plate (332) at positions corresponding to the two screws, and the electromagnetic semi-active local support device is rigidly connected to the follower side integrated plate (332) through the two screws; The outer shell (12) is provided with N radial through holes evenly distributed in the circumferential direction at a position where the outer shell (12) is embedded and in contact with the top cover (11), and the top cover (11) is provided with a threaded hole coaxial with each radial through hole, so that the top cover (11) and the outer shell (12) are rigidly connected by a threaded connection; The active side integrated board (331) is mounted on the main shaft of the milling robot, and the follower side integrated board (332) and the active side integrated board (331) are provided with three strong magnetic switches (31) at the peripheral outer edges of the relative surfaces of the two sides, which are in one-to-one correspondence and are flush with each other in height; the follower side integrated board (332) and the active side integrated board (331) are both provided with three balls (32) at multiple positions in one-to-one correspondence and are flush with each other in height on the relative surfaces of the two sides, and the height of the balls (32) on the same side integrated board protrudes above the height of the strong magnetic switches (31).

2. The fixture for magnetic mirror milling according to claim 1, characterized in that: The lower lubricating sleeve (14) and the center hole of the shell are in interference fit, and the bottom ends of the two are flush; the upper lubricating sleeve (13) and the center hole of the top cover are in interference fit.

3. The fixture for magnetic mirror milling according to claim 1, characterized in that: Four rectangular holes are evenly distributed along the circumference on the side wall of the housing (12) to reduce the structural mass and facilitate heat dissipation of the coil.

4. The fixture for magnetic mirror milling according to claim 1, characterized in that: The upper end of the wave mechanical spring (26) is higher than the shoulder position of the large diameter shaft section of the central shaft (22).

5. The fixture for magnetic mirror milling according to claim 4, characterized in that: The original length of the wave mechanical spring (26) is L1, the depth of the lower groove of the housing (12) is L2, the depth of the upper groove of the top cover (11) is L3, the height of each layer of the annular magnet (21) is H1, and the height of the hexagonal nut (25) is H2; L1-L2=H1, L3>H1, L3>H2; The thickness of the gap gasket (16) is adjustable, the movable component (2) is raised by the wave mechanical spring (26), the hexagonal nut (25) is located in the upper groove of the top cover (11), and the distance between the top of the uppermost first layer of annular magnets and the top surface of the top cover (11) is equal to d2; After the active side integrated plate (331) and the follower side integrated plate (332) are adsorbed, the wave mechanical spring (26) is compressed, and the amount of compression is equal to the height of the gap gasket (16).

6. The fixture for magnetic mirror milling according to claim 1, characterized in that: The ejector head gasket (24) and the milling cutter (34) are coaxial and located on both sides of the workpiece (35).

7. The fixture for magnetic mirror milling according to claim 1, characterized in that: The heights of the balls (32) on the integrated board on the same side are consistent, and the heights of the strong magnetic switches (31) on the integrated board on the same side are consistent.

8. The fixture for magnetic mirror milling according to claim 1, characterized in that: The connection between the push rod head gasket (24) and the push rod (23) is glue bonding.

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