Milling system for irregularly shaped parts with branch nozzles

Abstract

This application provides a milling machine machining system for irregularly shaped parts with branch nozzles, belonging to the field of forging technology. Addressing the problems of low machining accuracy and efficiency in milling irregularly shaped parts with branch nozzles, this application provides a milling machine machining system for such parts, including a machine tool drive module; an arm assembly connected to the machine tool drive module, the arm assembly including a first arm and a second arm drivenly connected to the end of the first arm; an edge-finding module, including an edge finder detachably connected to the second arm, a coordinate system establishment unit, and a path generation unit; and a machining module, including a radial tool holder detachably connected to the second arm and a cutting tool detachably connected to the radial tool holder. This application establishes a machining coordinate system for the branch nozzle through the edge-finding module, enabling one-time machining along the axial direction of the branch nozzle, improving the accuracy and quality of the finished product. Furthermore, the radial tool holder achieves both machine tool flexibility and improved machining efficiency.

Description

Technical Field

[0001] This application relates to the field of forging technology, and in particular to a milling machine system for machining irregularly shaped parts with branch nozzles. Background Technology

[0002] With the rapid development of the national equipment manufacturing industry, the demand for various types of irregular forgings is constantly increasing, and is gradually developing towards irregular shapes and large sizes.

[0003] like Figure 1 The aforementioned irregularly shaped part with branch nozzles is a key component in nuclear power plant evaporators. It is hemispherical in shape, with two branch nozzles and two circular ramps on its outer contour, and four square protrusions evenly distributed around its 90° perimeter.

[0004] Typically, when machining with a CNC milling machine, milling is performed layer by layer starting from the top of the part. The machining area can cover most of the part's outer contour, and the remaining area is contoured from the side. However, this machining method has two drawbacks. First, it divides the circular contour of the branch nozzle into at least two areas for machining. The reference points for the two machining operations are different. Due to the difference in the accuracy of the reference transfer, there will be a certain degree of tool transition step between the two machining operations, which affects the dimensional accuracy and machining quality of the branch nozzle, and thus the accuracy and quality of the part. Second, it requires high machine tool mobility, resulting in low machining efficiency. Summary of the Invention

[0005] The purpose of this application is to address the problems of low machining accuracy and low efficiency in the existing milling technology for irregularly shaped parts with branch nozzles. Therefore, this application provides a milling machining system for irregularly shaped parts with branch nozzles. By establishing a machining coordinate system for the branch nozzle through an edge-finding module, it enables one-time machining along the axial direction of the branch nozzle, improving the accuracy and quality of the finished product. Furthermore, by using a radial tool post, it achieves both machine tool flexibility and improved machining efficiency.

[0006] This application provides a milling system for machining irregularly shaped parts with branch nozzles. The part is hemispherical and has two branch nozzles and two circular ramps on its outer contour. Four square bosses are evenly distributed around its perimeter at 90° angles. Each square boss has a top surface, two parallel side surfaces, and a front surface. The top surface is parallel to the bottom plane of the part, and the two side surfaces and the front surface are perpendicular to the bottom plane of the part. The system includes:

[0007] Machine tool drive module;

[0008] An arm assembly connected to the machine tool drive module, the arm assembly including a first arm and a second arm that is drivenly connected to the end of the first arm, the first arm being capable of horizontal and vertical movement, and the second arm being capable of rotation and rotation about a direction perpendicular to the axis of the first arm;

[0009] The edge finding module includes an edge finder for detachable connection with the second arm, a coordinate system establishment unit, and a path generation unit;

[0010] The machining module includes a radial tool holder for detachable connection to the second arm and a cutting tool for detachable connection to the radial tool holder; wherein,

[0011] The coordinate system establishment unit is used to establish a processing coordinate system in cooperation with the arm assembly through the edge finder, and the processing coordinate system realizes the one-time processing and forming of the branch nozzle along the axial direction of the branch nozzle;

[0012] The path generation unit is used to perform an edge finding operation based on the machining coordinate system and in cooperation with the arm assembly through the edge finder, to obtain edge finding data, and to generate a tool path for the corresponding machining process based on the edge finding data.

[0013] The radial tool holder includes a base, a sliding mechanism, and a mounting rod for mounting the tool. The base is detachably connected to the end of the second arm. The sliding mechanism is disposed on the base and can drive the mounting rod to move in a direction perpendicular to the axial direction of the second arm.

[0014] The machine tool drive module is used to control the vertical movement of the first arm, the rotation of the second arm, and the sliding mechanism to move the mounting rod to the machining position according to the tool path.

[0015] By employing the above technical solution, the branch nozzle is precision machined using a milling machine, and a precise machining coordinate system for the branch nozzle is established using a coordinate system establishment unit. This enables machining along the axial direction of the branch nozzle, ensuring that the branch nozzle is machined in one pass and avoiding tool-jointing steps on the branch nozzle, thus improving the accuracy and quality of the finished product. Furthermore, the radial tool post converts the circumferential movement of the tool around the branch nozzle axis during machining from the horizontal movement of the first arm to the rotation of the second arm, thereby reducing the range of motion of the first arm (i.e., the machine tool). The first arm only needs to move vertically, while the second arm only rotates, achieving both overall flexibility of the arm assembly (i.e., the machine tool) and improved machining efficiency. At the same time, the machining position is adjusted through a sliding mechanism to ensure machining accuracy. Moreover, the radial tool post eliminates the need to change multiple different tools; only a single-specification turning tool is required to machine the branch nozzle, effectively reducing machining costs. The elimination of tool changes further improves machining efficiency and reduces tool maintenance difficulty.

[0016] In some embodiments, the coordinate system establishment unit performs the following steps:

[0017] S10. Obtain a blank, the blank having a bottom plane, an outer circular surface, four square bosses and a branch nozzle blank. Use a vertical lathe to finish the bottom plane and outer circular surface of the blank, and use a milling machine to finish the upper end face, two side end faces and front end face of the square bosses, as well as the end face of the branch nozzle blank.

[0018] S20. The second arm is equipped with an edge finder, which, together with the center of the ball of the blank and the end face of the square boss, determines the initial coordinate system.

[0019] S30. The blank is rotated to an angle corresponding to the branch nozzle blank by the milling machine turntable, and the initial coordinate system is rotated so that its Z-axis coincides with the center line of the branch nozzle blank to form a second coordinate system;

[0020] S40. Place the end face of the edge finder against the end face of the branch pipe blank to obtain the Z value of the end face of the branch pipe blank in the second coordinate system; replace the second arm with the processing module, and make the end face of the tool of the processing module against the end face of the oblique pipe nozzle, and reset the Z-axis 0 position of the second coordinate system according to the Z value to obtain the final processing coordinate system.

[0021] In some embodiments, S20, the second arm is equipped with an edge finder, which, in conjunction with the center of the blank and the end face of the square boss, determines an initial coordinate system, including:

[0022] S21. Rotate the blank to position B0 on ​​the B axis, install the edge finder on the second arm, and place the edge finder against the two side end faces of the square boss. Take the middle position of the two positions of the edge finder as position X0 on the X axis.

[0023] S22. The side of the edge finder is placed against the upper end face of the square boss, and the angle between the edge finder and the upper end face is equal to the angle between the branch nozzle of the part and the central axis of the part. The edge finder moves down a distance Z to the Z-axis position, Z = H0 + D / 2 × SIN(α).

[0024] S23. The edge finder keeps its angle unchanged, and its side is attached to the front end face of the square boss. The edge finder moves a distance Y towards the center axis of the blank, which is the Y-axis 0 position, Y = L0 + D / 2 × COS(α).

[0025] S24. Establish the initial coordinate system based on the X-axis 0 position, Y-axis 0 position, and Z-axis 0 position;

[0026] Wherein, D is the diameter of the edge finder, H0 is the distance between the upper end face of the square boss and the center of the blank ball, α is the angle between the branch nozzle of the part and the central axis of the part, and L0 is the distance between the front end face of the square boss and the center of the blank ball.

[0027] In some embodiments, the base extends in a direction perpendicular to the axial direction of the second arm and is detachably connected to the end of the second arm with the axis of the second arm as the center line;

[0028] The sliding mechanism includes a drive component and a lead screw drive assembly that are arranged and connected in a transmission along the extension direction of the base. A slider is provided on the lead screw drive assembly, and the mounting rod is provided on the side of the slider opposite to the base.

[0029] By adopting the above technical solution, the mounting rod on the base is positioned at a certain distance from the second arm through the base extending in a direction perpendicular to the axial direction of the second arm. This allows the rotation of the second arm to be converted into the circumferential movement of the mounting rod and the tool on it, which replaces the horizontal movement of the first arm. Furthermore, the sliding mechanism uses a lead screw drive to move the mounting rod, which improves the positioning accuracy and stability of the mounting rod movement, and has a strong load capacity, thus improving the stability of the tool.

[0030] In some embodiments, the base is connected to the second arm via a connecting handle, and a conductive slip ring is provided between the connecting handle and the base, and the machine tool drive module is connected to the drive component via the conductive slip ring.

[0031] In some embodiments, the connecting handle is a tapered handle, with the small end of the connecting handle connected to the second arm and the large end connected to the base.

[0032] In some embodiments, a dust cover is provided on one side of the base corresponding to the sliding mechanism, and the dust cover is provided with a clearance groove corresponding to the sliding path of the sliding mechanism, so as to allow the mounting rod to move.

[0033] In some embodiments, the cutting tool is a lathe tool.

[0034] In some embodiments, a monitoring module is further included, which is used to monitor the distance b between the cutting edge of the tool and the mounting rod;

[0035] The machine tool drive module determines the machining position based on the spacing b and the tool path, wherein the machining position is the spacing a between the mounting rod and the axis of the second arm;

[0036] The monitoring module or the machine tool drive module is also used to issue a tool change warning signal in response to the distance b being less than a first threshold.

[0037] In some embodiments, a monitoring module is further included, which is used to monitor the blade temperature of the cutting tool;

[0038] The machine tool drive module controls the rotation speed of the second arm based on the temperature.

[0039] Other features and corresponding beneficial effects of this application will be described in the latter part of the specification, and it should be understood that at least some of the beneficial effects will become obvious from the description in this application. Attached Figure Description

[0040] Figure 1 This is a structural schematic diagram of an irregularly shaped part with a branch nozzle provided in an embodiment of this application;

[0041] Figure 2 This is a schematic diagram of the conventional processing state of the parts in the embodiments of this application;

[0042] Figures 3(a)-(b) are schematic diagrams of the initial coordinate system established in the embodiments of this application, which coincide with the design datum. Figure 3(a) is the XZ axis view and Figure 3(b) is the XY axis view.

[0043] Figure 4 In this embodiment of the application, the edge finder is attached to the side end face of the square boss to center the X-axis 0 position;

[0044] Figure 5 In this embodiment of the application, the edge finder is attached to the upper surface of the square boss to set the Z-axis position to 0.

[0045] Figure 6 In this embodiment of the application, the edge finder is attached to the front end face of the square boss to set the Y-axis position to 0.

[0046] Figure 7 This is a schematic diagram of the X and Y axis 0-position conversion in the embodiments of this application;

[0047] Figures 8(a)-(b) are schematic diagrams of the second coordinate system established in the embodiments of this application, wherein Figure 8(a) is the XZ axis view and Figure 8(b) is the XY axis view;

[0048] Figure 9 This is a schematic diagram of a machine tool equipped with a radial tool holder machining the conical surface of a part's branch nozzle in an embodiment of this application;

[0049] Figure 10 This is a schematic diagram of the radial tool holder in an embodiment of this application;

[0050] Figure 11 This is a schematic diagram of the radial tool holder equipped with a dust cover in an embodiment of this application.

[0051] Explanation of reference numerals in the attached figures:

[0052] 1. Irregularly shaped part with a branch nozzle; 2. Branch nozzle; 3. Square boss; 31. Side end face; 32. Top end face; 33. Front end face;

[0053] 100. Arm assembly; 110. First arm; 120. Second arm; 200. Edge finder; 300. Cutting tool;

[0054] 400. Radial tool holder; 410. Base; 420. Sliding mechanism; 421. Drive component; 422. Lead screw; 423. Bearing housing; 424. Slider; 430. Mounting rod; 440. Connecting handle; 450. Conductive slip ring; 460. Dust cover. Detailed Implementation

[0055] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Although the description of this application is presented in conjunction with preferred embodiments, this does not mean that the features of this application are limited to this embodiment. On the contrary, the purpose of describing the application in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of this application. To provide a thorough understanding of this application, many specific details will be included in the following description. This application may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this application, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0056] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0057] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this application and for simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more. Unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or a connection within two elements. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0058] Please see Figure 1 , Figure 1 This is a structural schematic diagram of an irregularly shaped part 1 with a branch nozzle provided in an embodiment of this application.

[0059] The embodiments of this application are mainly for processing a non-circular part 1 with a branch nozzle and similar shaped parts. The part 1 is hemispherical and has two branch nozzles 2 and two circular ramps on its outer contour. Four square bosses 3 are evenly distributed around its perimeter at 90°. The square bosses 3 have an upper end face 32, two parallel side end faces 31 and a front end face 33. The upper end face 32 is parallel to the bottom plane of the part 1, and the two side end faces 31 and the front end face 33 are perpendicular to the bottom plane of the part 1.

[0060] Please see Figure 2 , Figure 2 This is a schematic diagram of the conventional processing state of part 1 in the embodiments of this application.

[0061] Typically, the finishing of the branch nozzle 2 of part 1 requires processing in at least two areas, with different datum points for the two processing steps. Figure 2 (This is a schematic diagram of one of the processing states). During processing, due to the difference in accuracy of the reference transfer, there will be a certain degree of tool connection step between the two processing steps, which will affect the dimensional accuracy and processing quality of the branch nozzle 2, and thus affect the accuracy and quality of part 1.

[0062] Meanwhile, when using the original machine tool for processing, the first arm 110 of the milling arm assembly 100 needs to move horizontally and vertically in real time to enable the milling cutter to process and shape the branch nozzle 2. The machine tool has a large range of motion and requires high flexibility, which results in low movement efficiency of the first arm 110, and thus low processing efficiency.

[0063] Furthermore, during the milling process, different cutting tools 300 need to be replaced depending on the working position. Specifically, for different positions of the branch nozzle 2, the cutting tools 300 are replaced with milling cutter discs, square shoulder milling cutters, first bullnose milling cutters (for forward machining of the workpiece), and second bullnose milling cutters (for inverted machining of the workpiece). This further reduces the machining efficiency, and the use and maintenance of multiple different cutting tools 300 will also increase costs.

[0064] Therefore, this application provides a milling system for irregularly shaped parts 1 with branch nozzles, including a machine tool drive module, an arm assembly 100, an edge finding module, and a processing module.

[0065] Specifically, the machine tool drive module and the arm assembly 100 can adopt the original machine tool drive module and rocker arm. That is, the machine tool drive module usually includes a power supply and a controller. The power supply provides power for the movement of the machine tool, and the controller controls the movement of the machine tool, such as the movement of the arm assembly 100.

[0066] Typically, the arm assembly 100 is connected to the machine tool drive module. Furthermore, the arm assembly 100 includes a first arm 110 and a second arm 120 that is drivenly connected to the end of the first arm 110. The first arm 110 can move horizontally and vertically (meaning it can move along the X, Y, and Z axes of the machining coordinate system), and the second arm 120 can rotate and spin about a direction perpendicular to the axis of the first arm 110, thereby enabling the tool 300 to move in all directions.

[0067] The edge finding module includes an edge finder 200 for detachable connection with the second arm 120, a coordinate system establishment unit, and a path generation unit. The edge finder 200, also known as a centering bar or center rod, is an important auxiliary tool in machine tool operation, primarily used for workpiece positioning.

[0068] The machining module includes a radial tool holder 400 detachably connected to the second arm 120 and a cutting tool 300 detachably connected to the radial tool holder 400. A turning tool is preferably used to perform turning operations, and the cutting tool 300 performs continuous linear cutting on the machined surface during machining, resulting in high dimensional accuracy and excellent surface quality of the machined part.

[0069] The coordinate system establishment unit is used to establish a machining coordinate system in cooperation with the arm assembly 100 through the edge finder 200. The machining coordinate system enables the branch nozzle 2 to be machined in one operation along the axial direction of the branch nozzle 2. That is, the machining coordinate system is transformed into a rotational coordinate system with the same angle as the branch nozzle 2. It can be machined along the axial direction of the branch nozzle 2, ensuring that the branch nozzle 2 is machined in one operation, avoiding the generation of tool-jointing steps on the branch nozzle 2, and improving the accuracy and quality of the finished product.

[0070] The path generation unit is used to perform edge finding operations based on the machining coordinate system, in cooperation with the edge finder 200 and the arm assembly 100, to acquire edge finding data and generate the tool path 300 for the corresponding machining process. Edge finding is an existing technology in machine tool operations. Typically, the edge finder 200 is installed at the end of the second arm 120, and the machine tool drive module controls the arm assembly 100 to move so that the edge finder 200 touches the edge of the workpiece to be machined, generating the corresponding edge finding data. Based on the edge finding data, the path generation unit uses the 3D software UG to adjust the digital model, defines the machining allowance for the corresponding machining process, and automatically generates the program using the software's machining function. In other words, the path generation unit converts the edge finding data into the tool path 300 for the corresponding machining process. The generation of the tool path 300 for the corresponding machining process using the 3D software UG based on the edge finding data is existing technology and will not be elaborated upon here.

[0071] The radial tool holder 400 includes a base 410, a sliding mechanism 420, and a mounting rod 430 for mounting the tool 300. The base 410 is detachably connected to the end of the second arm 120. The sliding mechanism 420 is disposed on the base 410 and can drive the mounting rod 430 to move in a direction perpendicular to the axial direction of the second arm 120.

[0072] The machine tool drive module is used to control the vertical movement of the first arm 110 and the rotation of the second arm 120 according to the path of the tool 300, and the sliding mechanism 420 to drive the mounting rod 430 to the machining position. That is, after the radial tool holder 400 is in the boring start position, it can be understood that the vertical movement of the first arm 110 is the movement along the Z-axis of the machining coordinate system, and the axis of the second arm 120 coincides with the Z-axis. The circumferential movement of the tool 300 around the axis of the branch nozzle 2 during the machining process is converted from the horizontal movement of the first arm 110 to the rotation of the second arm 120, thereby reducing the movement range of the first arm 110 (i.e., the machine tool). That is, the first arm 110 only needs to move vertically and the second arm 120 only needs to rotate, so as to improve the machining efficiency while taking into account the overall flexibility of the arm assembly 100 (i.e., the machine tool).

[0073] Meanwhile, the machining position can be adjusted by the sliding mechanism 420, that is, matched with the surface to be machined on the workpiece, which can ensure machining accuracy. The radial tool holder 400 can convert milling operation into turning operation, so that there is no need to change multiple different tools 300. Only the same specification turning tool can be used to machine the branch nozzle 2, effectively reducing the machining cost. Without the need to change tools, the machining efficiency can be further improved, and the maintenance difficulty of the tool 300 can be reduced.

[0074] Please refer to Figures 3-8. Figures 3(a)-(b) are schematic diagrams of the initial coordinate system established in the embodiments of this application, which coincides with the design datum. Figure 3(a) is the XZ axis view and Figure 3(b) is the XY axis view. Figure 4 In this embodiment of the application, the edge finder 200 is attached to the side end face of the square boss 3 to center the X-axis 0 position; Figure 5 In this embodiment of the application, the edge finder 200 is attached to the upper surface of the square boss 3 to set the Z-axis position to 0. Figure 6 In this embodiment of the application, the edge finder 200 is attached to the front end face of the square boss 3 to set the Y-axis position to 0. Figure 7 Figure 8(a)-(b) is a schematic diagram of the conversion of the X and Y axes to 0 position in the embodiments of this application; Figure 8(a)-(b) is a schematic diagram of the second coordinate system established in the embodiments of this application, wherein Figure 8(a) is the XZ axis view and Figure 8(b) is the YZ axis view.

[0075] In one implementation, the coordinate system establishment unit performs the following steps:

[0076] S10. Obtain the blank. The blank has a bottom plane, an outer circular surface, four square bosses 3, and a branch nozzle blank. The blank preparation can be carried out using conventional techniques in this field and belongs to the roughing process.

[0077] After the blank is transferred to the finishing process, the bottom plane and outer cylindrical surface of the blank are first finished using a vertical lathe. This serves as a reference datum for the milling machine machining, ensuring that the machining content of the vertical lathe is consistent with the machining content datum of the turning and milling machine. This step can also record the actual measured dimensions of the large outer diameter and the actual measured dimensions of the bottom plane from the center of the sphere (design datum), which will serve as a reference for establishing the datum of the subsequent turning and milling machine.

[0078] Then, a milling machine is used to finish the upper end face 32, the two side end faces 31, and the front end face 33 of the square boss 3, as well as the end face of the branch pipe blank. Specifically, this includes:

[0079] S11. After the blank is finished on the vertical lathe, it is transferred to the milling machine, and the central axis of the blank is made to coincide with the rotation center axis of the milling machine table. That is, the blank is placed in the center of the turntable of the lathe and milling machine, and the circle is checked to ensure that the central axis of the blank coincides with the rotation center axis of the turntable of the lathe and milling machine.

[0080] S12. Rotate the blank to any position directly opposite the square boss 3, and set the B axis to position 0.

[0081] Preferably, fine-tuning is performed by micro-rotation, and the front end face 33 of the square boss 3 is checked by dragging the dial indicator to determine the position of the blank directly facing the square boss 3. The dial indicator is also used to check the position of the square boss 3 on at least the left and right sides of the square boss 3 to verify the B-axis (rotation axis) 0 position.

[0082] Since the four square protrusions 3 are evenly distributed, they can be verified by the other square protrusions 3. Furthermore, they can be rotated by 90°, 180°, and 270° respectively, and the dial gauge can be dragged to verify that the remaining three square protrusions 3 are straight.

[0083] S13. Mill the top surface 32, the two side surfaces 31, and the front surface 33 of the square boss 3 with minimum quantity.

[0084] This step involves precision machining of each end face of the square boss 3, which serves as a measurement reference to ensure the accuracy of the subsequent coordinate system establishment.

[0085] Specifically, see Figure 7 The minimum amount of milling is used to flatten the upper surface 32 of the four square bosses 3 around the perimeter, and the two sides are milled according to the dimensional reference. The actual value of the distance from the upper surface 32 of the square bosses 3 to the bottom plane is measured by dial indicator. The distance from the bottom plane to the center of the sphere is accumulated and recorded as H0.

[0086] The front face 33 of the four square bosses 3 is milled flat with the minimum amount of milling. Based on the actual measured size of the outer circle, the actual measured value of the distance from the front face 33 of the machined and flattened square bosses 3 to the center of the ball is measured and recorded as L0.

[0087] Understandably, when machining the upper surface 32 of the four square bosses 3, the dimensions should be consistent to facilitate reference when setting the Z-axis 0 point later. When machining the side end face 31 of the square bosses 3 as a reference, the two sides should be symmetrical to be used for centering and determining the X-axis 0 point in the state of the mounted arm assembly 100.

[0088] S14. The second arm 120 in the adjusting arm assembly 100 has the same angle as the branch pipe nozzle blank. Preferably, it is fixed by a dial indicator, and the milling head presses the dial indicator to check the straightness and bevel of the front end face 33 of the square boss 3, verifying the angle of the second arm 120 to ensure that it is the same as the angle of the branch pipe nozzle blank. That is, the reference plane on the second arm 120 or the plane of the tool 300 is used to press the dial indicator or other testing tools, and then the second arm 120 is moved in the vertical angle direction. The accuracy of the angle is verified by the change of the dial indicator reading.

[0089] The blank is rotated to the corresponding angle of the branch nozzle blank via a turntable, and the end face of the branch nozzle blank is milled flat by the minimum amount of the machining tool 300 mounted on the second arm 120, which is used as a reference for subsequent transfer.

[0090] S20 and the second arm 120 are equipped with an edge finder 200, which, together with the center of the blank and the end face of the square boss 3, determine the initial coordinate system, which may specifically include:

[0091] S21. Rotate the blank to position 0 on the B axis. Install the edge finder 200 on the second arm 120 and place the edge finder 200 against the two side end faces 31 of the square boss 3. Take the midpoint between the two positions of the edge finder 200 as the position 0 on the X axis. See below. Figure 4 .

[0092] S22. Place the side of the edge finder 200 against the upper end face 32 of the square boss 3, with the angle between the edge finder 200 and the upper end face 32 being equal to the angle between the branch nozzle 2 of part 1 and the central axis of part 1. Move the edge finder 200 downwards a distance Z to the Z-axis position 0, where Z = H0 + D / 2 × SIN(α). See [reference needed] Figure 5 .

[0093] S23. The edge finder 200 maintains its angle and places its side against the front face 33 of the square boss 3. The edge finder 200 moves a distance Y towards the center axis of the blank, which is the Y-axis 0 position. Y = L0 + D / 2 × COS(α). See [reference needed]. Figure 6 .

[0094] S24. Establish an initial coordinate system based on the X-axis 0 position, Y-axis 0 position, and Z-axis 0 position, as shown in Figures 3(a)-(b). At this point, the initial machining datum and 0 position settings for part 1 in the arm assembly 100 state are complete.

[0095] Where D is the diameter of the edge finder 200, H0 is the distance between the upper end face 32 of the square boss 3 and the center of the blank ball, α is the angle between the branch nozzle 2 of part 1 and the central axis of part 1, that is, the angle between the center line of the branch nozzle blank and the central axis of the blank, and L0 is the distance between the front end face 33 of the square boss 3 and the center of the blank ball.

[0096] It should be noted that the X-axis 0, Y-axis 0, and Z-axis 0 obtained above refer to the planes where the X, Y, and Z coordinates are 0. The initial coordinate system is obtained by intersecting the three planes.

[0097] S30. Rotate the blank to the angle corresponding to the branch nozzle blank using the milling machine turntable. Since the machining datum is set at the center of the blank and the central axis of the blank coincides with the central axis of the turntable, the datum origin does not shift when the blank is rotated.

[0098] Rotate the initial coordinate system until its Z-axis coincides with the center line of the branch nozzle blank to form a second coordinate system. The rotation of the coordinate system can be completed by the machine tool program. The machine tool command for rotating the coordinate system is ROT X = -α, see Figures 8(a)-(b). At this point, the machining datum for machining along the branch nozzle 2 axis is completed.

[0099] However, this coordinate system is established when the edge finder 200 is clamped. After replacing it with the machining module, because the length of the machining module is not exactly the same as the length of the edge finder 200, the 0 position of the machining feed axis (Z-axis in this embodiment) needs to be reset. At this time, the end face of the branch nozzle 2 is used as the conversion reference for the front and rear Z-axis 0 positions, which can complete the reference conversion conveniently and accurately. At the same time, since the axis of the edge finder 200 or the machining tool 300 coincides with the axis of the second arm 120 when the edge finder 200 or the machining tool 300 is replaced, the 0 points of the remaining two axes do not need to be converted.

[0100] Therefore, it also includes:

[0101] S40. Place the end face of the edge finder 200 against the end face of the branch pipe blank to obtain the Z value of the end face of the branch pipe blank in the second coordinate system.

[0102] Replace the second arm 120 with the machining module. Place the end face of the tool 300 in the machining module against the end face of the oblique nozzle. According to the Z value, reset the Z-axis 0 position of the second coordinate system through the machine tool program to obtain the final machining coordinate system. At this point, the coordinate system and 0 position setting of the arm assembly 100 machining the branch nozzle 2 in the state of clamping the tool 300 are completed.

[0103] Please see Figure 9-11 , Figure 9 This is a schematic diagram of a machine tool equipped with a radial tool holder 400 machining the conical surface of the branch nozzle 2 of part 1 in an embodiment of this application; Figure 10 This is a schematic diagram of the radial tool holder 400 in an embodiment of this application; Figure 11 This is a schematic diagram of the radial tool holder 400 equipped with a dust cover 460 in an embodiment of this application.

[0104] In one embodiment, the base 410 extends in a direction perpendicular to the axial direction of the second arm 120, such that the mounting rod 430 disposed on the base 410 is at a certain distance from the second arm 120, thereby converting the rotation of the second arm 120 into circumferential movement of the mounting rod 430 and the tool 300 thereon, which replaces the horizontal movement of the first arm 110. Furthermore, the base 410 is detachably connected to the end of the second arm 120 with the axis of the second arm 120 as its centerline, which improves the stability of the base 410 and facilitates maintenance of the radial tool holder 400.

[0105] The sliding mechanism 420 includes a drive component 421 and a lead screw transmission assembly arranged and connected along the extension direction of the base 410. A slider 424 is mounted on the lead screw transmission assembly, and a mounting rod 430 is mounted on the side of the slider 424 facing away from the base 410. That is, the sliding mechanism 420 uses lead screw transmission to move the mounting rod 430, improving the positioning accuracy and stability of the mounting rod 430's movement, and also providing a strong load capacity, thus improving the stability of the tool 300. Preferably, the drive component 421 is a servo motor and a matching gearbox.

[0106] In one embodiment, bearing seats 423 are symmetrically arranged at the bottom of the base 410, and the lead screw 422 of the lead screw drive assembly is connected to the bearing seats 423, thereby improving the transmission stability.

[0107] It is understandable that, in order to achieve stable movement of slider 424 under the drive of the lead screw transmission assembly, a limit mechanism is connected between slider 424 and base 410.

[0108] In one embodiment, the base 410 is connected to the second arm 120 via a connecting handle 440, and a conductive slip ring 450 is provided between the connecting handle 440 and the base 410. The machine tool drive module is connected to the drive unit 421 via the conductive slip ring 450, thereby facilitating wiring.

[0109] In one embodiment, the connecting shank 440 is a tapered shank, with its small end connected to the second arm 120 and its large end connected to the base 410, to better fit the second arm 120. Preferably, the connecting shank 440 is a BT60 tool holder.

[0110] In one embodiment, a dust cover is provided on one side of the corresponding sliding mechanism 420 of the base 410 to improve the protection of the radial tool holder 400 and extend its service life. Correspondingly, the dust cover is provided with a relief groove corresponding to the sliding path of the sliding mechanism 420 to allow the mounting rod 430 to move.

[0111] In one embodiment, the system further includes a monitoring module for monitoring the distance b between the cutting edge of the tool 300 and the mounting rod 430.

[0112] The machine tool drive module determines the machining position based on the spacing b and the path of the tool 300. The machining position is the spacing a between the axis of the mounting rod 430 and the axis of the second arm 120.

[0113] Assuming the new tool 300 is installed on the mounting rod 430, the distance between the cutting edge of the tool 300 and the mounting rod 430 is a1. In the corresponding machining path of the tool 300, the theoretical distance between the mounting rod 430 and the axis of the second arm 120 is c1. After the tool 300 has been machining the surface for a period of time, the monitoring module measures the distance between the cutting edge and the mounting rod 430 as d1. The wear dimension of the cutting edge is then a1-d1. This wear dimension is then compensated into the distance of the tool 300 machining path so that the actual distance between the mounting rod 430 and the axis of the second arm 120 is c1-(a1-d1), that is, the actual distance between the mounting rod 430 and the axis of the second arm 120 is c1-a1+d1.

[0114] In one embodiment, the monitoring module or machine tool drive module is also configured to issue a tool change warning signal in response to the spacing b being less than a first threshold, i.e., the tool 300 is too worn, so as to replace the tool 300 in a timely manner to ensure that the radial tool holder 400 performs accurate and effective machining on the surface to be machined.

[0115] In one embodiment, the monitoring module is used to monitor the cutting edge temperature of the tool 300. In this case, the monitoring module may include an infrared temperature probe.

[0116] The machine tool drive module controls the rotation speed of the second arm 120 according to the temperature to balance processing efficiency and safety.

[0117] In one implementation, the monitoring module or machine tool drive module is further configured to issue an overheat warning signal in response to a temperature exceeding a second threshold.

[0118] In one implementation, the tool change warning signal or overheat warning signal includes, but is not limited to, audible warnings and photoelectric warnings.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A milling system for machining irregularly shaped parts with branch nozzles, the part being hemispherical with two branch nozzles and two circular ramps on its outer contour, and four square bosses evenly distributed at 90° around its perimeter, wherein each square boss has a top surface, two parallel side surfaces, and a front surface, the top surface being parallel to the bottom plane of the part, and the two side surfaces and the front surface being perpendicular to the bottom plane of the part, characterized in that... The system includes: Machine tool drive module; An arm assembly connected to the machine tool drive module, the arm assembly including a first arm and a second arm that is drivenly connected to the end of the first arm, the first arm being capable of horizontal and vertical movement, and the second arm being capable of rotation and rotation about a direction perpendicular to the axis of the first arm; The edge finding module includes an edge finder for detachable connection with the second arm, a coordinate system establishment unit, and a path generation unit; The machining module includes a radial tool holder for detachable connection to the second arm and a cutting tool for detachable connection to the radial tool holder; wherein, The coordinate system establishment unit is used to establish a processing coordinate system in cooperation with the arm assembly through the edge finder, and the processing coordinate system realizes the one-time processing and forming of the branch nozzle along the axial direction of the branch nozzle; The path generation unit is used to perform an edge finding operation based on the machining coordinate system and in cooperation with the arm assembly through the edge finder, to obtain edge finding data, and to generate a tool path for the corresponding machining process based on the edge finding data. The radial tool holder includes a base, a sliding mechanism, and a mounting rod for mounting the tool. The base is detachably connected to the end of the second arm. The sliding mechanism is disposed on the base and can drive the mounting rod to move in a direction perpendicular to the axial direction of the second arm. The machine tool drive module is used to control the vertical movement of the first arm, the rotation of the second arm, and the sliding mechanism to move the mounting rod to the machining position according to the tool path.

2. The milling system for irregularly shaped parts with branch nozzles according to claim 1, characterized in that, The coordinate system establishment unit performs the following steps: S10. Obtain a blank, the blank having a bottom plane, an outer circular surface, four square bosses and a branch nozzle blank. Use a vertical lathe to finish the bottom plane and outer circular surface of the blank, and use a milling machine to finish the upper end face, two side end faces and front end face of the square bosses, as well as the end face of the branch nozzle blank. S20. The second arm is equipped with an edge finder, which, together with the center of the ball of the blank and the end face of the square boss, determines the initial coordinate system. S30. The blank is rotated to an angle corresponding to the branch nozzle blank by the milling machine turntable, and the initial coordinate system is rotated so that its Z-axis coincides with the center line of the branch nozzle blank to form a second coordinate system; S40. Place the end face of the edge finder against the end face of the branch pipe blank to obtain the Z value of the end face of the branch pipe blank in the second coordinate system; replace the second arm with the processing module, and make the end face of the tool of the processing module against the end face of the oblique pipe nozzle, and reset the Z-axis 0 position of the second coordinate system according to the Z value to obtain the final processing coordinate system.

3. The milling system for irregularly shaped parts with branch nozzles according to claim 2, characterized in that, S20 The second arm is equipped with an edge finder, which, in conjunction with the center of the ball of the blank and the end face of the square boss, determines the initial coordinate system, including: S21. Rotate the blank to position B0 on ​​the B axis, install the edge finder on the second arm, and place the edge finder against the two side end faces of the square boss. Take the middle position of the two positions of the edge finder as position X0 on the X axis. S22. The side of the edge finder is placed against the upper end face of the square boss, and the angle between the edge finder and the upper end face is equal to the angle between the branch nozzle of the part and the central axis of the part. The edge finder moves down a distance Z to the Z-axis position, Z = H0 + D / 2 × SIN(α). S23. The edge finder keeps its angle unchanged, and its side is attached to the front end face of the square boss. The edge finder moves a distance Y towards the center axis of the blank, which is the Y-axis 0 position, Y = L0 + D / 2 × COS(α). S24. Establish the initial coordinate system based on the X-axis 0 position, Y-axis 0 position, and Z-axis 0 position; Wherein, D is the diameter of the edge finder, H0 is the distance between the upper end face of the square boss and the center of the blank ball, α is the angle between the branch nozzle of the part and the central axis of the part, and L0 is the distance between the front end face of the square boss and the center of the blank ball.

4. The milling system for irregularly shaped parts with branch nozzles according to claim 1, characterized in that, The base extends in a direction perpendicular to the axial direction of the second arm and is detachably connected to the end of the second arm with the axis of the second arm as the center line; The sliding mechanism includes a drive component and a lead screw drive assembly that are arranged and connected in a transmission along the extension direction of the base. A slider is provided on the lead screw drive assembly, and the mounting rod is provided on the side of the slider opposite to the base.

5. The milling system for irregularly shaped parts with branch nozzles according to claim 4, characterized in that, The base is connected to the second arm via a connecting handle, and a conductive slip ring is provided between the connecting handle and the base. The machine tool drive module is connected to the drive component via the conductive slip ring.

6. The milling system for irregularly shaped parts with branch nozzles according to claim 4, characterized in that, The connecting handle is a tapered handle, with the small end of the connecting handle connected to the second arm and the large end connected to the base.

7. The milling system for irregularly shaped parts with branch nozzles according to claim 1, characterized in that, A dust cover is provided on one side of the base corresponding to the sliding mechanism, and the dust cover is provided with a clearance groove corresponding to the sliding path of the sliding mechanism to allow the mounting rod to move.

8. The milling system for irregularly shaped parts with branch nozzles according to claim 1, characterized in that, The cutting tool is a lathe tool.

9. The milling system for irregularly shaped parts with branch nozzles according to any one of claims 1-8, characterized in that, It also includes a monitoring module, which is used to monitor the distance b between the cutting edge of the tool and the mounting rod; The machine tool drive module determines the machining position based on the spacing b and the tool path, wherein the machining position is the spacing a between the mounting rod and the axis of the second arm; The monitoring module or the machine tool drive module is also used to issue a tool change warning signal in response to the distance b being less than a first threshold.

10. The milling system for irregularly shaped parts with branch nozzles according to any one of claims 1-8, characterized in that, It also includes a monitoring module, which is used to monitor the cutting edge temperature of the tool; The machine tool drive module controls the rotation speed of the second arm based on the temperature.

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