Annular groove machining method and annular groove machining system

Abstract

The invention provides an annular groove machining method and an annular groove machining system. The annular groove machining method comprises the steps that a workpiece to be machined is provided, and an annular groove is machined in the workpiece; a rotary cutter is provided, the rotary cutter is provided with an annular grinding part, and the width of the grinding part in the radial direction of the rotary cutter is smaller than the radial width of the annular groove; the rotating axis of spinning of the rotating cutter is configured to be parallel to the central axis of the annular groove and deviate by a certain distance; the rotating cutter rotates around the rotating axis, meanwhile, the rotating cutter and the workpiece move relatively, so that the rotating axis does circular motion relative to the central axis, and the motion trail of the grinding part covers the whole radial width range of the annular groove; and the rotary cutter is fed relative to the workpiece in the direction of the rotation axis so that the annular groove can be machined in the workpiece. Therefore, the tool abrasion can be reduced, the machining time is shortened, and the tool consumption is reduced.

Description

Technical Field

[0001] This disclosure relates to the field of machining technology, and more specifically, to a method and system for machining annular grooves. Background Technology

[0002] In fields such as semiconductor manufacturing, it is often necessary to machine annular grooves on the end faces of rotating parts made of hard and brittle materials such as silicon carbide (SiC) and ceramics.

[0003] In related technologies, annular groove machining typically employs a cutting tool (e.g., an electroplated diamond grinding wheel) with a width matching that of the annular groove to be machined. During machining, the center of rotation of the cutting tool needs to coincide with the center of the annular groove, and the cutting tool directly cuts into the workpiece along the axial direction.

[0004] However, this processing method tends to cause significant tool wear, resulting in longer processing times and a larger number of tools consumed. Summary of the Invention

[0005] This section provides a general overview of this disclosure, rather than a full disclosure of the entire scope or all features of this disclosure.

[0006] In a first aspect, this disclosure provides a method for machining an annular groove. The method includes providing a workpiece to be machined, on which an annular groove is to be machined; A rotary cutting tool is provided, the rotary cutting tool having an annular grinding section, the width of the grinding section in the radial direction of the rotary cutting tool being smaller than the radial width of the annular groove; The axis of rotation of the rotating tool is configured to be parallel to the central axis of the annular groove, but offset by a certain distance; The rotary tool is made to spin about its axis of rotation, while simultaneously moving relative to the workpiece, so that the axis of rotation moves in a circular motion relative to the central axis, thereby ensuring that the motion trajectory of the grinding section covers the entire radial width of the annular groove; and The rotary tool is fed relative to the workpiece along the direction of the rotation axis to machine an annular groove on the workpiece.

[0007] Secondly, this disclosure provides an annular groove machining system, including a support device, a drive device, and a controller. The support device is used to support the workpiece to be machined, on which an annular groove is to be machined. The drive device is used to mount and drive a rotary tool to rotate. The rotary tool has an annular grinding section, the width of which in the radial direction is smaller than the radial width of the annular groove. The controller is configured to control the drive device and the support device such that the rotation axis of the rotary tool is parallel to and offset by a certain distance from the central axis of the annular groove. The rotary tool rotates around the rotation axis, and simultaneously the rotary tool and the workpiece move relative to each other in the circumferential direction of the annular groove, so that the rotation axis moves in a circle relative to the central axis. This allows the movement trajectory of the grinding section to cover the entire radial width range of the annular groove, and the rotary tool feeds relative to the workpiece in the direction of the rotation axis to machine the annular groove on the workpiece. Attached Figure Description

[0008] The features and advantages of embodiments of the present disclosure will become more readily understood from the following description with reference to the accompanying drawings. The drawings are not drawn to scale and some features may be enlarged or reduced to show details of specific components. In the drawings: Figure 1 This is an exploded view of an annular groove machining system according to an embodiment of the present disclosure.

[0009] Figure 2 for Figure 1 The front view of the annular groove machining system shown.

[0010] Figure 3 This is a flowchart of a method for machining an annular groove according to an embodiment of the present disclosure.

[0011] Figure 4 This is a diagram showing the positional relationship between the grinding section and the workpiece at a certain moment in the annular groove machining method according to an embodiment of the present disclosure.

[0012] Figure 5 To pass Figure 3 A schematic diagram of an annular groove produced by the annular groove machining method described in the figure.

[0013] Figure 6 This is a schematic diagram of the structure of a rotary cutting tool according to an embodiment of the present disclosure.

[0014] Figure 7 This is a schematic diagram of the structure of a rotary cutter according to another embodiment of the present disclosure.

[0015] Figure 8 To pass Figure 7 A schematic diagram of the annular groove machined by a rotary cutting tool.

[0016] In the accompanying drawings, the same or corresponding technical features or components are represented by the same or corresponding reference numerals. Detailed Implementation

[0017] The technical solutions in this disclosure will now be clearly and completely described with reference to the accompanying drawings.

[0018] It should be noted that, for clarity, not all features of a particular embodiment are described or shown in the specification and drawings. Furthermore, to avoid unnecessary details obscuring the technical solutions of interest in this disclosure, only the device structure closely related to the technical solutions of this disclosure is described and shown in the specification and drawings, while other details that are not closely related to the technical content of this disclosure and are known to those skilled in the art are omitted.

[0019] First, before detailing the specific structure of this application, the technical problem to be solved by this application will be elaborated in depth.

[0020] As mentioned above, in the related technology, when machining an annular groove on the end face of a workpiece made of hard and brittle material (such as SiC), the rotation center of the tool coincides with the center of the annular groove. That is, the tool rotates around the center to machine, thereby forming the annular groove.

[0021] In this method, the width of the cutting tool is the same as the width of the annular groove to be machined. This means the chip removal channel is narrow or even closed, making it difficult for grinding chips to be discharged. The accumulation of chips affects the coolant's reach to the cutting position of the tool, further leading to severe heat buildup and resulting in severe tool wear, thus affecting tool life. To avoid overheating, the tool speed needs to be reduced, which increases machining time and reduces machining efficiency. Moreover, once the worn tool can no longer meet the process requirements, it needs to be replaced, further increasing the number of tools consumed.

[0022] Furthermore, since the cutting tool and the annular groove have the same width, the contact area between them is relatively large, resulting in greater cutting resistance for the tool. This also exacerbates tool wear; moreover, because hard and brittle materials are extremely sensitive to tensile stress, excessive cutting resistance can easily lead to micro-cracks, breakage, or even large-scale chipping on the groove wall and edges, affecting machining accuracy.

[0023] In view of this, according to the embodiments of the present disclosure, a method and system for machining annular grooves are provided.

[0024] To facilitate understanding of the technical solution disclosed herein, the following will first refer to... Figure 1 and Figure 2 The annular groove machining system 100 that performs the annular groove machining method is described in detail.

[0025] The annular groove machining system 100 includes a support device 120, a drive device 140, and a controller 180.

[0026] For example, the annular groove machining system 100 can be constructed using a computer numerical control (CNC) machine tool.

[0027] The support device 120 is used to support the workpiece 200 to be processed, and the workpiece 200 is to be processed to have an annular groove 200a.

[0028] For example, the support device 120 may only serve to support the workpiece 200. Alternatively, the support device 120 may also include a turntable 122, the rotatable portion 122a of which is rotatable about its central axis to support the workpiece 200 and drive the workpiece 200 to rotate synchronously. It is conceivable that the support device 120 may be the worktable of a CNC machine tool.

[0029] In addition, the support device 120 may also include a tooling 124, wherein the workpiece 200 is fixed on the tooling 124, and the tooling 124 is fixed on a rotatable part 122a of, for example, a turntable 122.

[0030] Workpiece 200 can be fixed to fixture 124, for example, by using wax. For workpiece 200 made of hard and brittle materials, clamping with a mechanical vise or clamping plate can easily generate clamping stress, making workpiece 200 prone to deformation or even breakage after processing. Fixing with wax can provide uniform adhesion and avoid local stress concentration.

[0031] The tooling 124 can be placed on the rotatable portion 122a in a manner coaxial with the rotatable portion 122a of the turntable 122. For example, as Figure 1 As shown, multiple holes can be opened on the end face of the rotatable part 122a to fix the tooling 124 by vacuum adsorption; or, the tooling 124 can also be fixed on the rotatable part 122a by clamping, for example, a three-jaw chuck.

[0032] The drive unit 140 is used to mount and drive the rotary cutter 160 to rotate, the rotary cutter 160 having an annular grinding section 162.

[0033] For example, the drive unit 140 may be the spindle unit of a CNC machine tool for mounting and driving a tool to rotate, and may feed along the Z-axis and adjust its position in the XY plane.

[0034] The controller 180 can be electrically connected to the carrier 120 and the drive 140 and configured to control the coordinated operation of the carrier 120 and the drive 140 to achieve a specific machining trajectory.

[0035] Below, in conjunction with reference Figures 2 to 5Based on the above-described annular groove machining system 100, an annular groove machining method according to an embodiment of the present disclosure will be described.

[0036] The method for machining the annular groove includes the following steps: Step S310: Provide a workpiece 200 to be processed, the workpiece 200 to be machined with an annular groove 200a (see... Figure 5 ).

[0037] In this step, the workpiece 200 is securely mounted on the support device 120. The workpiece 200 can be made of hard and brittle materials such as silicon carbide or ceramics.

[0038] Step S320: Provide a rotary tool 160, which has an annular grinding section 162. It should be noted that the width (i.e., grinding wall thickness) W1 of the grinding section 162 in the radial direction of the rotary tool 160 is designed to be smaller than the radial width W2 of the annular groove 200a to be machined.

[0039] Step S330: Configure the rotation axis C1 of the rotating tool 160 to be parallel to the central axis C2 of the annular groove 200a, and offset by a certain distance D.

[0040] In this step, the controller 180 can control the drive device 140 or the carrier device 120 to move in the horizontal plane, so that the rotation center of the rotating tool 160 does not coincide with the geometric center of the annular groove 200a to be processed, but is offset by a precisely calculated eccentricity D.

[0041] Step S340: The rotary tool 160 is made to spin around the rotation axis C1, and the rotary tool 160 is made to move relative to the workpiece 200, so that the rotation axis C1 moves in a circle relative to the central axis C2, thereby making the movement trajectory of the grinding part 162 cover the entire radial width range of the annular groove 200a, and the rotary tool 160 is fed relative to the workpiece 200 along the direction of the rotation axis C1, so as to machine the annular groove 200a on the workpiece 200.

[0042] It is understandable that the relative movement of the rotary tool 160 and the workpiece 200, so that the rotation axis C1 moves in a circle relative to the central axis C2, can be achieved by the rotary tool 160 spinning in a fixed position and the workpiece 200 moving, so that the rotation axis C1 moves in a circle relative to the central axis C2; or by the workpiece 200 being fixed and the rotary tool 160 moving, so that the rotation axis C1 moves in a circle relative to the central axis C2.

[0043] In this step, the rotary tool 160 generates a cutting speed by rotating at high speed, and the relative motion between the rotary tool 160 and the workpiece 200 allows the offset rotary tool 160 to "sweep" across the entire radial width of the annular groove 200a. At the same time, the axial feed motion causes the material of the workpiece 200 to be removed layer by layer in the depth direction until the preset groove depth is reached.

[0044] The machining method of this embodiment allows the use of a rotary tool 160 with a width W1 smaller than the groove width W2, combined with an eccentric distance D, to machine the annular groove 200a. Because the rotary tool 160 is eccentrically positioned and has a thinner wall, a spacious gap is formed between the non-cutting side of the tool and the groove wall during machining. This gap becomes an efficient chip removal channel and coolant channel, allowing chips to be smoothly discharged and coolant to directly reach the cutting point to remove heat, thus avoiding heat accumulation, slowing tool wear, and consequently reducing the number of tools consumed. Good cooling and chip removal conditions allow for higher cutting parameters, thereby shortening machining time and improving machining efficiency. Simultaneously, eccentric machining transforms the original full-width surface contact into local line contact or small-area arc surface contact, thereby reducing cutting resistance, which not only slows tool wear and extends tool life but also reduces the risk of workpiece edge chipping due to excessive cutting force, improving machining quality and accuracy.

[0045] Regarding the relative motion mentioned in step S340, refer to... Figure 2 and Figure 4 Different motion strategies can be adopted according to the actual equipment conditions.

[0046] One implementation method is to make the workpiece 200 spin around the central axis C2 while keeping the position of the rotation axis C1 fixed.

[0047] In this mode, the rotary tool 160 is always tangent to the inner diameter of the annular groove 200a at one end in the radial direction, and always tangent to the outer diameter of the annular groove 200a at the other end. As the workpiece 200 rotates, the rotation axis C1 of the rotary tool 160 rotates in a circular motion relative to the central axis C2 of the workpiece 200. The rotary tool 160 forms countless motion trajectories in the annular groove 200a, covering the entire radial width range of the annular groove 200a, and finally machining the annular groove 200a.

[0048] For example, the controller 180 can control the turntable 122 of the support device 120 to rotate around the central axis C2, thereby driving the workpiece 200 to rotate around the central axis C2. At the same time, the drive device 140 drives the rotating tool 160 to spin around the rotation axis C1, so as to realize the relative movement between the rotating tool 160 and the workpiece 200.

[0049] This method can make full use of the rotational accuracy of the turntable, which is beneficial to improving the roundness of the machined annular groove 200a. At the same time, the centrifugal force generated by the rotation helps with chip removal and cooling, thereby allowing for higher cutting parameters and thus improving machining efficiency.

[0050] Another implementation method is to keep the workpiece 200 fixed while making the rotation axis C1 revolve around the central axis C2.

[0051] In this mode, the rotary tool 160 is always externally tangent to the inner diameter of the annular groove 200a at one end along the radial direction, and is always internally tangent to the outer diameter of the annular groove 200a at the other end. The rotation axis C1 of the rotary tool 160 moves in a circular motion around the central axis C2, thereby forming countless tracks covering the entire radial width range of the annular groove 200a, and finally machining the annular groove 200a.

[0052] For example, the controller 180 can control the drive device 140 to drive the rotary cutter 160 to rotate on its own axis and revolve around the central axis C2, so that the rotation axis C1 of the rotary cutter 160 makes circular motion around the central axis C2.

[0053] This method requires a high degree of machine tool flexibility, but does not require the workpiece to rotate 200 degrees, making it particularly suitable for machining workpieces with irregular shapes, excessively large dimensions, or those that are difficult to dynamically balance.

[0054] In some embodiments, the machining method further includes adjusting the distance D according to the radial width of the annular groove 200a to be machined, so as to machine annular grooves 200a with different radial widths using the same rotary tool 160.

[0055] In traditional processes, machining grooves of different widths requires changing to different specifications of cutting tools. In this embodiment, the eccentric distance D is an adjustable parameter. Therefore, during the machining process, it is not necessary to change the cutting tools; only the distance D needs to be adjusted to machine annular grooves 200a of different widths, thus improving the machining efficiency of annular grooves 200a.

[0056] It is understandable that the larger the distance D, the larger the width of the annular groove 200a. The distance D can be achieved by the controller 180 controlling the drive device 140 to drive the rotary cutter 160 to generate displacement in the radial direction of the annular groove 200a. For example, the drive device 140 can drive the rotary cutter 160 to move radially along the annular groove 200a; or, the drive device 140 can drive the rotary cutter 160 to move in a direction that forms a certain angle with the radial direction of the annular groove 200a, etc.

[0057] In some implementations, such as Figure 4 As shown, the distance D is half the sum of the radial width W1 of the grinding section 162 and the radial width W2 of the annular groove 200a.

[0058] When the eccentricity D is at this value, during the circular motion, the outer cutting edge trajectory of the rotary tool 160 coincides exactly with the outer diameter of the annular groove 200a, and simultaneously, the inner cutting edge trajectory of the rotary tool 160 coincides exactly with the inner diameter of the annular groove 200a. Therefore, during one revolution of the rotary tool 160 around the center of the annular groove 200a, it can simultaneously complete the grinding and shaping of both the inner and outer walls of the groove, thus achieving material removal with the shortest path and improving processing efficiency.

[0059] In some implementations, such as Figure 6 As shown, the rotary tool 160 is a hollow tubular structure, and the grinding part 162 is located at the end of the hollow tubular structure.

[0060] The rotary cutter 160 is designed with a hollow tubular structure, which can utilize the edge with a high linear velocity for cutting. Therefore, it has good cutting consistency, low axial resistance, and good machining stability, making it more suitable for removing hard and brittle materials.

[0061] It is conceivable that, for example Figure 6 As shown, the annular grinding section 162 of the rotary tool 160 may include multiple cutting edges, which are arranged in annularly to form a multi-edge synchronous cutting structure.

[0062] This multi-blade synchronous cutting structure allows for the formation of the 200a annular groove in a single feed, eliminating the need for multiple passes. Simultaneously, the tool's chip removal groove design is adapted to the chip removal path of annular cutting, ensuring smooth chip discharge along the circumference. This reduces tool wear and machining interruptions caused by poor chip removal, improving machining efficiency. Furthermore, the uniform cutting force distribution reduces the probability of tool chipping and wear, extending tool life, reducing the frequency of tool changes and sharpening, and lowering overall machining costs.

[0063] In some embodiments, the grinding section 162 is made of diamond particles and a sintering binder by a sintering process.

[0064] Traditional cutting tools are typically electroplated, with only a layer of abrasive grains attached to the surface, which becomes ineffective once worn. In contrast, the sintering process used in this embodiment mixes diamond abrasive grains with a sintering binder (such as copper-based or iron-based metal binders), resulting in abrasive grains distributed throughout the entire depth direction of the grinding section 162. This structure gives the tool excellent "self-sharpening" properties; as the binder wears down, new, sharp abrasive grains are continuously exposed to participate in cutting, thus maintaining a consistently high cutting capability. This wear-resistant characteristic allows the tool to withstand prolonged, high-intensity grinding loads, effectively extending tool life and reducing the rate of tool wear in the machining of hard and brittle materials.

[0065] In some implementations, such as Figure 7 As shown, the rotary tool 160 has a plurality of concentrically arranged annular grinding portions 162, and the plurality of grinding portions 162 are spaced apart in the radial direction for simultaneously machining a plurality of corresponding concentric annular grooves 200a.

[0066] By setting multiple concentric annular grinding sections 162, and arranging these sections radially at intervals, multiple annular grooves 200a can be simultaneously completed with a single rotational feed, eliminating the need for multiple tool changes and feeds. Figure 8 The grinding process (as shown) improves machining efficiency. Furthermore, the multiple grinding sections 162 are coaxially designed with the tool rotation center, ensuring that the rotational reference of all annular grooves 200a is completely consistent during machining. This fundamentally avoids concentricity errors caused by clamping deviations and tool runout during multi-stage machining. This improves the concentricity and positional accuracy of the multiple grooves.

[0067] In some implementations, such as Figure 7 As shown, the cutting edges of adjacent grinding sections 162 are arranged in the same radial direction.

[0068] The cutting edges of adjacent grinding sections 162 are arranged in the same radial direction, allowing the generated chips to be discharged in the same direction. A smooth chip removal channel is formed by the pre-set chip removal grooves on the tool, preventing interference and blockage of chips from different radial cutting edges in the groove gaps. This prevents debris from remaining in the grooves and being further scraped by the grinding edges, reducing the probability of scratches and chipping on the groove walls. The radially aligned distribution of the cutting edges also ensures uniform load distribution across the grinding sections 162 during tool rotation, reducing excessive stress and rapid dulling of cutting edges at any particular radial position. Improved wear uniformity also extends the effective machining time of the tool, reduces premature tool changes due to localized wear, and lowers machining costs.

[0069] Of course, it is conceivable that the cutting edges of adjacent grinding sections 162 can be staggered in the same radial direction.

[0070] Although this disclosure has been described with reference to exemplary embodiments, it should be understood that this disclosure is not limited to the specific embodiments described and shown herein. Various changes can be made to the exemplary embodiments by those skilled in the art without departing from the scope defined by the claims of this disclosure.

[0071] The features mentioned and / or shown in the foregoing description of exemplary embodiments of this disclosure may be combined in the same or similar manner with one or more other embodiments, combined with features in other embodiments, or substituted for corresponding features in other embodiments. Such combinations or substitutions should also be considered as including within the scope of protection of this disclosure.

Claims

1. A method for machining an annular groove, characterized in that, include: Provide a workpiece to be processed, the workpiece to be processed to have an annular groove; A rotary cutting tool is provided, the rotary cutting tool having an annular grinding section, the width of the grinding section in the radial direction of the rotary cutting tool being smaller than the radial width of the annular groove; The axis of rotation of the rotating tool is configured to be parallel to the central axis of the annular groove, but offset by a certain distance; The rotating tool is made to spin around the axis of rotation, and the rotating tool is made to move relative to the workpiece, so that the axis of rotation moves in a circle relative to the central axis, thereby making the movement trajectory of the grinding part cover the entire radial width range of the annular groove. as well as The rotary cutter is fed relative to the workpiece along the direction of the rotation axis to machine the annular groove on the workpiece.

2. The method for processing annular grooves according to claim 1, characterized in that, The relative motion includes: causing the workpiece to spin around the central axis while keeping the position of the rotation axis fixed; or keeping the workpiece fixed while causing the rotation axis to revolve around the central axis.

3. The method for processing annular grooves according to claim 1, characterized in that, The annular groove machining method further includes: adjusting the distance according to the radial width of the annular groove to be machined, so as to machine annular grooves with different radial widths using the same rotary tool.

4. The method for processing annular grooves according to claim 3, characterized in that, The distance is half the sum of the radial width of the grinding section and the radial width of the annular groove.

5. The method for processing annular grooves according to claim 1, characterized in that, The rotating cutting tool has a hollow tubular structure, and the grinding section is located at the end of the hollow tubular structure.

6. The method for processing annular grooves according to claim 1, characterized in that, The grinding section is made of diamond particles and a sintering binder through a sintering process.

7. The method for processing annular grooves according to claim 1, characterized in that, The rotary tool has a plurality of concentric annular grinding portions, which are spaced apart in the radial direction to simultaneously process the corresponding plurality of concentric annular grooves.

8. The method for processing annular grooves according to claim 7, characterized in that, The cutting edges of adjacent grinding sections are arranged in the same radial direction.

9. The method for machining annular grooves according to claim 1, characterized in that, The workpiece is made of silicon carbide and is fixed to the tooling by wax adhesion.

10. A system for machining annular grooves, characterized in that, include: A support device for supporting a workpiece to be processed, on which an annular groove is to be machined; A driving device for mounting and driving a rotary cutter to rotate, the rotary cutter having an annular grinding section, the width of the grinding section in the radial direction of the rotary cutter being smaller than the radial width of the annular groove; as well as The controller is configured to control the drive unit and the carrier unit such that: The axis of rotation of the rotating tool is parallel to the central axis of the annular groove, but offset by a certain distance; The rotating tool spins around the rotation axis, while the rotating tool moves relative to the workpiece, so that the rotation axis moves in a circle relative to the central axis, thereby making the motion trajectory of the grinding part cover the entire radial width range of the annular groove; as well as The rotary cutter is fed relative to the workpiece along the direction of the rotation axis to machine the annular groove on the workpiece.

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