A spiral milling method for blisk annular cutter based on blade center cutter axis control line

Abstract

The invention discloses a method for spiral milling of an integral blade disk with an annular cutter based on a blade center tool axis control line. The method comprises the following steps: constructing a first offset curved surface according to a machining curved surface of a blade to be machined, and constructing a second offset curved surface according to a check curved surface; generating a plurality of swinging cutter planes according to the first offset curved surface, and generating a corresponding non-interference cutter axis swing curve according to each swinging cutter plane; fitting a plurality of non-interference cutter axis swing curves to obtain a non-interference blade center point tool axis control surface; generating a non-interference blade center point tool axis control line on the tool axis control surface along a cutting direction; and calculating a tool center point tool axis control line according to the non-interference blade center point tool axis control line. The invention can avoid the defect that the tool center point of the annular cutter corresponds to a plurality of different positions and the problem that the tool center point changes due to a change in a tool axis vector by directly searching for the interference blade center point tool axis control line based on the law that the blade center point of the annular cutter is unchanged, thereby reducing the problem that it is difficult to generate the tool axis control line of the annular cutter.

Description

Technical Field

[0001] The invention belongs to the technical field of numerical control machining, and in particular relates to a spiral milling method of an annular cutter for an integral blade disk based on a blade center cutter axis control line. Background Art

[0002] In the design of new aircraft engine fans, compressors and turbines, in order to further improve engine performance, the integral blade disk structure is widely used. The integral blade disk designs the blades and the wheel disk into an integral structure, achieving the purpose of weight reduction, grade reduction and efficiency improvement, eliminating the tenons, mortise and tenon grooves and locking devices used for traditional connections, reducing the structural weight and the number of parts, avoiding the tenon airflow loss, and greatly simplifying the engine structure; at the same time, the integral blade disk adopts new wide chord, swept blades and narrow flow channels in the aerodynamic layout, further improving the aerodynamic efficiency. The materials of the integral blade disk are mostly difficult to cut materials such as titanium alloys and high-temperature alloys, and have process characteristics such as thin walls, easy deformation, poor rigidity, and large cutting margins. Only by using advanced CNC precision cutting processing technology can the strict requirements of high-performance aircraft engines on part forming accuracy and quality be met.

[0003] The integral blade disk is a complex spatial rotating body structure. The blades on the blade disk require multi-coordinate CNC machining technology, which involves complex tool axis interference processing and tool axis control methods. Especially when spiral milling is used, the thickness of the leading and trailing edges of the blade is extremely small, and the tool axis is prone to sudden changes.

[0004] The control of the tool axis has always been one of the core issues in CNC machining of complex structural parts. For multi-axis CNC machining, ball-end tools are widely used because of their simple structure, curvature adaptability of the ball head part, and the fact that the tool center point remains unchanged when the tool axis changes. Compared with ball-end tools, annular tools have better cutting performance, relatively longer tool life, and higher machining efficiency. However, annular tools also have some disadvantages. The tool center point of annular tools moves with the change of tool axis. Therefore, the programming algorithm of annular tools is more complicated, and the difficulty of tool axis control increases, which limits the application of annular tools in complex parts. Summary of the invention

[0005] The purpose of the present invention is to provide a method for spiral milling of an integral blade disk annular cutter based on a blade center tool axis control line. The blade center point tool axis of the annular cutter is taken as the control object, the blade center point tool axis control line of the annular cutter is constructed, and then the blade center point tool axis control line is used to generate a tool axis vector, thereby reducing the problem of difficulty in generating the annular cutter tool axis control line.

[0006] The present invention adopts the following technical solution: a method for spiral milling of an annular blade of an integral blade disk based on a blade center cutter axis control line, comprising the following steps:

[0007] A first offset curved surface is constructed according to the machining curved surface of the blade to be machined, and a second offset curved surface is constructed according to the inspection curved surface; the inspection curved surface and the machining curved surface are located on both sides of the same machining channel;

[0008] Generating a plurality of tool swinging planes according to the first offset curved surface, and generating a corresponding non-interference tool axis swinging curve according to each tool swinging plane;

[0009] Fitting several non-interference tool axis swing curves to obtain the non-interference tool axis control surface at the blade center point;

[0010] Generate a tool axis control line without interference of blade center point on the tool axis control surface along the cutting direction;

[0011] The tool center point tool axis control line is calculated based on the tool center point tool axis control line without interference.

[0012] Further, generating a plurality of swinging knife planes according to the first offset curved surface includes:

[0013] Based on each blade center point on the first offset surface, a surface normal vector n of the first offset surface is generated;

[0014] Calculate the vector b perpendicular to the feed direction and the surface normal vector;

[0015] The swinging knife plane corresponding to the blade center point is generated based on the surface normal vector and vector b.

[0016] Furthermore, generating a corresponding non-interference tool axis swing curve according to each tool swing plane includes:

[0017] Selecting a blade center point in the swinging knife plane, determining a first critical knife axis vector and a second critical knife axis vector according to the blade center point, and generating a fan-shaped area according to the first critical knife axis vector and the second critical knife axis vector;

[0018] The radius of the rotating cylindrical surface is calculated according to the processing channel depth and the maximum rotation radius of the blisk, and the rotating cylindrical surface is generated with the rotation center of the blisk as the central axis and the radius of the rotating cylindrical surface as the radius;

[0019] Calculate the intersection arc of the sector area and the rotating cylindrical surface as the non-interference tool axis swing arc corresponding to the blade center point;

[0020] The intersection of the non-interference tool axis swing arcs corresponding to all blade center points in the tool swing plane is calculated as the non-interference tool axis swing curve.

[0021] Further, generating a tool axis control line without interference of the blade center point on the tool axis control surface along the cutting direction includes:

[0022] For the blade center point on the first offset surface, find the corresponding non-interference tool axis swing curve on the non-interference blade center point tool axis control surface;

[0023] Based on the blade center point and the two endpoints of the non-interference tool axis swing curve, two critical vectors are generated; and the rotation angle of the machine tool rotation axis is calculated according to the two critical vectors, and the rotation angle set [Φ i ,Ψ i ]; where Φ i is the first rotation angle corresponding to the i-th blade center point, Ψ i is the second rotation angle corresponding to the i-th blade center point;

[0024] Determine the tool axis control line of the non-interference blade center point based on all rotation angle sets.

[0025] Further, determining the tool axis control line of the non-interference blade center point according to all rotation angle sets includes:

[0026] Select the maximum value of all first rotation angles Φ max and the minimum value of all second rotation angles Ψ min ;

[0027] According to Φ max and min Determine the tool axis control line without interference from the blade center point.

[0028] Furthermore, according to Φ max and min Determine the tool axis control line without interference blade center point including:

[0029] When Φ max ≤Ψ min When selecting the tool axis control line with no interference from the blade center point, select the tool axis control line with no interference from the blade center point in the common range of the swing range of the machine tool rotary axis;

[0030] When Φ max >Ψ min When the rotation angle set corresponding to all blade center points is taken as a known quantity, the linear interpolation method is used to select the tool axis control line of the blade center point without interference.

[0031] Furthermore, the tool center point tool axis control line calculated based on the non-interference blade center point tool axis control line includes:

[0032] For the blade center point P on the tool axis control line without interference e , generate the tool axis vector T of the blade center point;

[0033] The vector V is obtained by cross-producting the tool axis vector T at the blade center and the surface normal vector n. a ;

[0034] Calculate the perpendicular to the vector V a The vector V of the tool axis vector T at the blade center point b ;

[0035] In vector V bFind the distance from the blade center point P in the direction e The point (Rr) is taken as the center point of the ring knife.

[0036] Further, constructing the first offset curved surface according to the machining curved surface of the blade to be machined includes:

[0037] The machining surface is offset toward the center of the machining channel, and the offset distance is the radius r of the annular cutter bottom edge.

[0038] Further, constructing the second offset curved surface according to the inspection curved surface includes:

[0039] The inspection surface is offset toward the center of the machining channel by a distance of (2×Rr), where R is the radius of the annular cutter.

[0040] Another technical solution of the present invention: an integral blade disk annular cutter spiral milling device based on a blade center cutter axis control line, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned integral blade disk annular cutter spiral milling method based on a blade center cutter axis control line when executing the computer program.

[0041] The beneficial effects of the present invention are: the present invention, through the law that the center point of the annular blade remains unchanged, can avoid the defect that the center point of the annular knife corresponds to multiple different positions and the problem that the center point changes due to the change of the knife axis vector by directly finding the interference blade center point and knife axis control line, thereby reducing the problem of the difficulty in generating the annular knife knife axis control line. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A diagram of a ring knife model in an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of a swinging knife plane is created in an embodiment of the present invention;

[0044] Figure 3 Schematic diagram of critical tool axis vector analysis in an embodiment of the present invention;

[0045] Figure 4 It is a schematic diagram of solving the swing curve of the blade center point of the annular knife without interference in the embodiment of the present invention;

[0046] Figure 5 Schematic diagram of the knife axis control surface of the annular knife without interference of the blade center point in the embodiment of the present invention;

[0047] Figure 6 (a) is a schematic diagram of a solution model in which the rotation angle of the machine tool rotation axis has a common interval in an embodiment of the present invention, Figure 6 (b) is a schematic diagram of a solution model for a rotation angle of a machine tool rotation axis without a common interval in an embodiment of the present invention;

[0048] Figure 7 Schematic diagram of a ring knife position solution model in an embodiment of the present invention;

[0049] Figure 8 The control line diagram of the annular knife in the embodiment of the present invention; DETAILED DESCRIPTION

[0050] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] The present invention takes the blade profile of an integral blade disk as an example and gives specific implementation steps. The present invention discloses an integral blade disk annular cutter spiral milling method based on a blade center tool axis control line, comprising the following steps: constructing a first offset surface according to the machining surface of the blade to be machined, and constructing a second offset surface according to the inspection surface; the inspection surface and the machining surface are located on both sides of the same machining channel; generating a number of swinging cutter planes according to the first offset surface, and generating a corresponding non-interference tool axis swing curve according to each swinging cutter plane; fitting a number of non-interference tool axis swing curves to obtain a non-interference blade center point tool axis control surface; generating a non-interference blade center point tool axis control line on the tool axis control surface along the cutting direction; and calculating the tool center point tool axis control line according to the non-interference blade center point tool axis control line.

[0052] The present invention uses the law that the center point of the annular blade remains unchanged and directly searches for the tool axis control line of the interference blade center point, thereby avoiding the defect that the center point of the annular knife corresponds to multiple different positions and the problem that the center point changes due to the change of the tool axis vector, thereby reducing the difficulty in generating the tool axis control line of the annular knife.

[0053] In the embodiment of the present invention, the model of the annular knife is as follows: Figure 1 As shown, R is the tool radius of the annular knife, r is the bottom edge radius of the annular knife, and the blade center point P e is the distance from the tangent point P on the tangent point normal vector n c The point is r, the blade center point is the tool axis T e The point P passing through the center of the circular blade e The tool axis vector line.

[0054] The annular cutter touches the machined surface at point P. c There are many different tool cutting postures. When the tool is in different positions, the center point of the ring tool and the tool axis are in different positions. Directly controlling the tool axis at the center point of the ring tool will cause the center point to change due to the change of the tool axis vector. e Therefore, controlling the tool axis at the blade center point can avoid this problem.

[0055] In an embodiment of the present invention, in order to obtain discrete blade center points and perform tool axis interference inspection, it is necessary to offset the machining surface to the inner side of the channel by the annular tool bottom edge radius r, and make a pipe surface with a radius of r at the blade tip line, taking a quarter of it to prevent interference between the tool and the blade tip; that is, constructing the first offset surface according to the machining surface of the blade to be machined includes: offsetting the machining surface to the center direction of the machining channel, and the offset distance is the annular tool bottom edge radius r. Similarly, the inspection surface on the other side of the machining channel is offset to the inner side of the channel (2×Rr), and making a pipe surface with a radius of (2×Rr) at the blade tip line, taking a quarter of it, to obtain an offset surface of the inspection surface; that is, constructing the second offset surface according to the inspection surface includes: offsetting the inspection surface to the center direction of the machining channel, and the offset distance is (2×Rr), where R is the annular tool radius.

[0056] After the offset surface is constructed, it is necessary to create a swinging tool plane. In the embodiment of the present invention, the method for creating the swinging tool plane for five-axis machining is as follows: Figure 2 As shown, generating a plurality of swinging tool planes according to the first offset surface includes: generating a surface normal vector n of the first offset surface based on each blade center point on the first offset surface; calculating a vector b perpendicular to the feed direction and the surface normal vector; and generating a swinging tool plane corresponding to the blade center point based on the surface normal vector and the vector b.

[0057] In addition, in order to generate a swinging knife plane that is not heavily dependent on the surface normal vector and changes smoothly, the surface normal vector can be used to create the swinging knife plane at some key positions, while the vector obtained by quaternion interpolation is used to replace the surface normal vector at other positions. The vector b in the above method is replaced by a vector pointing to the centroid of the blade from a point on the blade rotation axis that is at the same height as the centroid of the blade.

[0058] Specifically, given two specified initial vectors q 1 (x 1 ,y 1 ,z 1 ) and q n (x n ,y n ,z n ), interpolate between these two vectors to get q i The calculation formula is:

[0059]

[0060] Where θ = arccos(q 1 ·q n ), t is the spherical linear interpolation parameter.

[0061] The intermediate vectors obtained by quaternion interpolation change continuously and evenly, and because they fall on the arc surface, the vector modulus lengths obtained are all unit lengths.

[0062] The distance between each plane is determined by the machining accuracy. A series of intersection lines can be obtained by intersecting the swing cutter plane with the created blade offset surface. These intersection lines are discretized into points of a certain distance to obtain the blade center point in the swing cutter plane.

[0063] In practical applications, we first analyze the geometric characteristics of the blade, and select the surface normal vectors at several representative contact points as key vectors. These contact points are generally located in the transition area between the leading and trailing edges of the blade and the blade body, and in areas with a small feasible domain of the tool axis. Then, the interpolation vectors of the intermediate contact points are calculated based on the normal vectors at these points.

[0064] Next, generating a corresponding non-interference tool axis swing curve according to each swinging tool plane includes: selecting a blade center point in the swinging tool plane, determining a first critical tool axis vector and a second critical tool axis vector according to the blade center point, and generating a fan-shaped area according to the first critical tool axis vector and the second critical tool axis vector; calculating the radius of the rotating cylindrical surface according to the processing channel depth and the maximum rotation radius of the integral blade disk, and generating a rotating cylindrical surface with the rotation center of the integral blade disk as the center axis and the radius of the rotating cylindrical surface as the radius; calculating the intersection arc of the fan-shaped area and the rotating cylindrical surface as the non-interference tool axis swing arc corresponding to the blade center point; calculating the intersection of the non-interference tool axis swing arcs corresponding to all the blade center points in the swinging tool plane as the non-interference tool axis swing curve.

[0065] According to the control line-based machining principle and the characteristics of the open integral blade disk structure, there are two critical tool axis vectors at each blade center point, that is, the non-interference blade center point tool axis swing interval of each blade center point is a fan-shaped area. Specifically, the annular blade center point tool axis is confined within the swinging plane, and there are two critical tool axis vectors. The blade center point tool axis swing interval is a fan-shaped area with these two critical tool axis vector lines as the boundary. For the two critical tool axis vectors within the swinging plane, as Figure 3 As shown, one of them is the self-interference critical tool axis vector T c1 , obtained by the interference check of the processed blade; the other critical tool axis vector is the interference critical tool axis vector T c2 , obtained from adjacent blades or other interference conditions. In most areas of the blade body, the interference inspection surface is mainly the adjacent curved surface of the machined blade, while in the leading and trailing edge areas of the blade and a small part of the blade body, there is no interference between the tool and the adjacent blade.

[0066] The critical tool axis vector is obtained by searching for critical points on critical constraints. Figure 3 As shown in the figure, when the critical constraint is the processed surface, the search target of the critical point is:

[0067]

[0068] Among them, C 0 is the intersection equation of the offset surface of the machined surface and the swing cutter plane, C 0 (t 0 ) is the intersection line C 0 The position vector of any point on the p It is the unit projection vector of the normal vector of the tangent contact point on the swinging knife plane.

[0069] Similarly, when the critical constraint is an adjacent surface, the search target of the critical point is:

[0070]

[0071] Among them, C 1 is the intersection equation of the adjacent curved surface offset surface and the swing cutter plane, C 1 (t 0 ) is the intersection line C 1 The position vector of any point on the

[0072] A fan-shaped area with these two critical tool axis vector lines as boundaries is obtained, and then a rotating cylindrical surface is constructed with the rotation center of the blade disk as the central axis and the sum of the maximum rotation radius of the blade disk and half of the channel depth as the radius. The intersection of the non-interference blade center point tool axis swing fan-shaped area of ​​any blade center point with the rotating cylindrical surface can obtain a circular arc line, which is the non-interference tool axis swing arc at this blade center point.

[0073] Taking the intersection of the non-interference tool axis swing arcs of all blade center points in a swinging tool plane as the non-interference tool axis swing interval of the swinging tool plane, a non-interference tool axis swing curve C can be obtained. com ,like Figure 4 The vector lines connecting any blade center point in the swinging knife plane and any point on the curve are all non-interference blade center point knife axis vector lines.

[0074] According to the above steps, the non-interference blade center point tool axis swing curves in all the swinging knife planes are obtained, and these curves are called the non-interference blade center point tool axis swing curve group C. set .like Figure 5 As shown in the figure, the surface generated by fitting these curves is the tool axis control surface S without interference of the blade center point k , any point on the control surface can be used as the tool axis control point.

[0075] In an embodiment of the present invention, generating a tool axis control line without interference of blade center point on the tool axis control surface along the cutting direction includes:

[0076] For the blade center point on the first offset surface, the corresponding non-interference tool axis swing curve is found on the non-interference blade center point tool axis control surface; two critical vectors are generated based on the blade center point and the two endpoints of the non-interference tool axis swing curve; and the rotation angle of the machine tool rotation axis is calculated based on the two critical vectors, and combined into a rotation angle set [Φ i ,Ψ i ]; where Φ i is the first rotation angle corresponding to the i-th blade center point, Ψ i is the second rotation angle corresponding to the i-th blade center point; the tool axis control line of the non-interference blade center point is determined according to all rotation angle sets.

[0077] Specifically, determining the non-interference blade center point tool axis control line according to all rotation angle sets includes: selecting the maximum value of all first rotation angles Φ max and the minimum value of all second rotation angles Ψ min According to Φ max and min Determine the tool axis control line without interference from the blade center point.

[0078] More specifically, according to Φ max and min Determine the tool axis control line without interference blade center point including:

[0079] When Φ max ≤Ψ min When Φ, select the tool axis control line without interference of blade center point in the common range of the machine tool rotary axis swing range; when Φ max >Ψ min When the rotation angle set corresponding to all blade center points is taken as a known quantity, the linear interpolation method is used to select the tool axis control line of the blade center point without interference.

[0080] That is, in the embodiment of the present invention, the control line is generated according to the following criteria:

[0081] 1) The control line should ensure that the tool axis vector changes smoothly;

[0082] 2) The tool axis vector generated based on the control line should try to ensure that the machine tool table rotation axis does not reverse or reverses as little as possible.

[0083] A curve is generated on the tool axis control surface of the non-interference blade center point along the cutting direction as the tool axis control line. In the embodiment of the present invention, a machine tool rotation axis can be randomly selected for optimization, and after optimization, other rotation axes must correspond to the law of the rotation axis.

[0084] In this embodiment, the rotation axis A is taken as an example for explanation, the tool axis and the tool swing plane are nearly parallel, a mathematical model of fixed value and linear interpolation is established for the rotation axis A, and the rotation axis B can be obtained after the rotation axis A is determined. The present invention directly optimizes the machine tool rotation angle in the machining coordinate system, and generates a tool axis control line on the tool axis control surface without interference of the blade center point.

[0085] 1) The two critical tool axis vectors are converted into angles A and B of machine tool rotation to obtain the feasible domain of the tool axis in the machine tool coordinate system.

[0086] 2) Establish a two-dimensional rectangular coordinate system with the rotation angle A of the machine tool rotation axis and the cumulative arc length S of the cutting contact point as the coordinate axis. The feasible domain A angle range of the tool axis corresponding to all the cutting contact points in the blade back area is [Φ i ,Ψ i ]. Let the sequence {Φ 1 ,Φ 2 ,…,Φ w The maximum value among them is Φ=Φ max , the series {Ψ 1 ,Ψ 2 ,…,Ψ w The minimum value of Ψ=Ψ min .

[0087] 3) If Φ≤Ψ, it means that the swing range of the rotation axis A of this cutting line has a common interval, and the A-axis can be fixed for processing. The angle values ​​of all the edge center points on the middle edge center line are (Φ+Ψ) / 2, such as Figure 6 (a) shown.

[0088] 4) If Φ>Ψ, it means that the rotation angle A has no common range, and the A-axis cannot be fixed for processing. The A-axis linear interpolation method is used for processing, such as Figure 6 As shown in (b), in this embodiment, the line with the largest absolute value of slope in the line set is taken as the final linear interpolation equation, and the rotation angle value of each blade center point can be obtained by interpolation using this linear equation. After conversion, the optimal non-interference blade center point tool axis control line can be obtained.

[0089] In one embodiment, the tool center point tool axis control line is calculated based on the non-interference tool center point tool axis control line, including: for the tool center point P on the non-interference tool center point tool axis control line e , generate the tool axis vector T at the blade center point; obtain the vector V by cross-producting the tool axis vector T at the blade center point and the surface normal vector n a ; Calculate the perpendicular to the vector V a The vector V of the tool axis vector T at the blade center point b ; In vector V b Find the distance from the blade center point P in the direction e The point (Rr) is taken as the center point of the ring knife.

[0090] More specifically, Figure 7 As shown, take any blade center point P on the offset surface of the machined surface e is the research object, the normal vector of this point on the surface is n, and the solution process of the tool position point is as follows:

[0091] 1) Use the cross product of the tool axis vector T and the normal vector n to get the vector V a At the same time, the blade center point P e is the origin, vector V a As the normal vector, we can get plane S a (and V a Since the axis of the circular cutter is parallel to the axis of the blade center, and the axis must intersect the normal vector n, the axis of the cutter is on this plane S. a Inside.

[0092] 2) Make a perpendicular line to vector V a and the vector V of T b , V b =V a ×T. According to the annular knife model, the line connecting the blade center point and the knife center point is perpendicular to the knife axis, so the vector V b That is, the blade center point points in the direction of the knife center point.

[0093] 3) Distance from blade center point P e In vector V b The point with Rr in the direction is the center point of the circular knife. After obtaining the center point, the knife axis line is naturally obtained.

[0094] In summary, the knife center point P o for:

[0095]

[0096] According to the geometric relationship of the end of the annular knife, it can be known that the knife tip point P t for:

[0097]

[0098] Using the method used in the present invention, the knife axis control line finally generated is as follows: Figure 8 As shown in the figure (the white line in the figure is the tool center point tool axis control line), this method is weakly dependent on the geometric properties of the machined surface. The tool axis vector mainly depends on the tool axis control line. If the tool axis control line is smooth, the generated tool axis vector is generally smooth. Therefore, the tool axis vector changes smoothly and is not prone to sudden changes, and it can avoid interference between tools during the cutting process. The present invention can effectively reduce the difficulty of controlling the tool axis of the annular tool, and can ensure that there is no obvious sudden change in the rotating axis of the machine tool during processing, effectively improving the stability of the processing process, and thus improving the surface processing quality of the blade.

[0099] The present invention also discloses an integral blade disk annular cutter spiral milling device based on a blade center cutter axis control line, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned integral blade disk annular cutter spiral milling method based on a blade center cutter axis control line is implemented.

[0100] The above-mentioned device can be a computing device such as a desktop computer, a notebook, a PDA, and a cloud server. The device may include but is not limited to a processor and a memory. Those skilled in the art will appreciate that the device may include more or fewer components, or a combination of certain components, or different components, for example, it may also include input and output devices, network access devices, etc.

[0101] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0102] In some embodiments, the memory may be an internal storage unit of the device, such as a hard disk or memory of the device. In other embodiments, the memory may also be an external storage device of the device, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the device. Further, the memory may also include both an internal storage unit of the device and an external storage device. The memory is used to store an operating system, an application program, a boot loader (BootLoader), data, and other programs, such as the program code of the computer program, etc. The memory may also be used to temporarily store data that has been output or is to be output.

[0103] It should be noted that the specific content of the above-mentioned device is based on the same concept as the embodiment of the method of the present invention. Its specific functions and technical effects can be found in the method embodiment part, and will not be repeated here.

Claims

1. A method for spiral milling of an annular blade of an integral blade disk based on a blade center and a cutter axis control line, characterized in that: The following steps are involved: A first offset curved surface is constructed according to the machining curved surface of the blade to be machined, and a second offset curved surface is constructed according to the inspection curved surface; the inspection curved surface and the machining curved surface are located on both sides of the same machining channel; Generating a plurality of tool swinging planes according to the first offset curved surface, and generating a corresponding non-interference tool axis swinging curve according to each of the tool swinging planes; The non-interference tool axis swing curves are fitted to obtain the non-interference tool axis control surface at the blade center point; R is the tool radius of the annular tool, r is the bottom blade radius of the annular tool, and the blade center point P e is the distance from the tangent point P on the tangent point normal vector n c The point is r, the blade center point is the tool axis T e The point P passing through the center of the circular blade e The knife axis vector line; Generating a tool axis control line without interference of blade center point on the tool axis control surface along the cutting direction; The tool center point tool axis control line is calculated according to the non-interference tool center point tool axis control line; Generating a plurality of swinging knife planes according to the first offset curved surface comprises: Based on each blade center point on the first offset curved surface, generating a surface normal vector n of the first offset curved surface; Calculate a vector b perpendicular to the feed direction and the surface normal vector; Generate a swinging knife plane corresponding to the blade center point based on the surface normal vector and vector b; Generating a corresponding non-interference tool axis swing curve according to each of the tool swing planes includes: Selecting a blade center point in the swinging knife plane, determining a first critical knife axis vector and a second critical knife axis vector according to the blade center point, and generating a fan-shaped area according to the first critical knife axis vector and the second critical knife axis vector; Calculate the radius of the cylindrical surface of revolution according to the depth of the machining channel and the maximum rotation radius of the blisk, and generate the cylindrical surface of revolution with the rotation center of the blisk as the central axis and the radius of the cylindrical surface of revolution as the radius; Calculate the intersection arc of the sector area and the rotating cylindrical surface as the non-interference tool axis swing arc corresponding to the blade center point; Calculating the intersection of the non-interference tool axis swing arcs corresponding to all blade center points in the tool swing plane as the non-interference tool axis swing curve; Generating a tool axis control line without interference of blade center point on the tool axis control surface along the cutting direction comprises: For the blade center point on the first offset curved surface, searching for the corresponding non-interference tool axis swing curve on the non-interference blade center point tool axis control surface; Based on the blade center point and the two endpoints of the non-interference tool axis swing curve, two critical vectors are generated; and the rotation angle of the machine tool rotation axis is calculated according to the two critical vectors, and combined into a rotation angle set [Φ i ,Ψ i ]; where Φ i is the first rotation angle corresponding to the i-th blade center point, Ψ i is the second rotation angle corresponding to the i-th blade center point; Determine the tool axis control line of the non-interference blade center point according to all the rotation angle sets; The tool center point tool axis control line calculated according to the non-interference blade center point tool axis control line includes: For the blade center point P on the tool axis control line without interference e , generate the tool axis vector T of the blade center point; The vector V is obtained by cross-producting the tool axis vector T at the blade center point and the surface normal vector n. a ; Calculate the perpendicular to the vector V a The vector V of the tool axis vector T at the blade center point b ; In vector V b Find the distance from the blade center point P in the direction e The point (Rr) is taken as the center point of the ring knife; Constructing a first offset curved surface according to the machining curved surface of the blade to be machined includes: The machining curved surface is offset toward the center direction of the machining channel, and the offset distance is the radius r of the annular cutter bottom edge; The second offset surface constructed according to the inspection surface includes: The inspection surface is offset toward the center direction of the processing channel by a distance of (2×Rr), wherein R is the radius of the annular cutter.

2. The method for spiral milling of an annular blade of an integral blade disk based on the blade center and tool axis control line according to claim 1, wherein determining the non-interference blade center point and tool axis control line according to all the rotation angle sets comprises: Select the maximum value of all first rotation angles Φ max and the minimum value of all second rotation angles Ψ min ; According to Φ max and min Determine the tool axis control line without interference from the blade center point.

3. A method for spiral milling of an annular blade of an integral blade disk based on a blade center and axle control line according to claim 2, characterized in that: According to Φ max and min Determine the tool axis control line without interference blade center point including: When Φ max ≤Ψ min When selecting the tool axis control line with no interference from the blade center point, select the tool axis control line with no interference from the blade center point in the common range of the swing range of the machine tool rotary axis; When Φ max >Ψ min When the rotation angle set corresponding to all blade center points is taken as a known quantity, the linear interpolation method is used to select the tool axis control line of the blade center point without interference.

4. A blisk annular cutter spiral milling device based on blade center cutter axis control line, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for spiral milling of an annular blade of an integral blade disk based on the blade center and tool axis control line as described in any one of claims 1 to 3 is implemented.

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