A processing technology for motor hole of new energy motor housing

Abstract

The present invention discloses a process for machining a motor hole in a new energy motor housing, which belongs to the field of die-cast aluminum alloy machining technology and comprises the following steps: (1) clamping the motor housing on a hydraulic fixture and installing a rough machining tool on the spindle of a dual-spindle horizontal five-axis machining center; (2) rough machining the motor hole with the rough machining tool, wherein the single-side allowance of the motor hole diameter is 0.15mm±0.05 and the bottom allowance is 0.2mm±0.05; (3) installing a tool for machining a recess groove on the spindle of the dual-spindle horizontal five-axis machining center and fine-machining the recess groove plane at the bottom of the motor hole; (4) installing a finishing tool on the spindle of the dual-spindle horizontal five-axis machining center and finishing the motor hole with the finishing tool. The present invention can ensure the precision requirements of the motor hole such as cylindricity, coaxiality, and position, and can improve the machining quality while improving the machining efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of die-cast aluminum alloy machining, and in particular relates to a machining process for a motor hole of a new energy motor housing. Background Art

[0002] At present, with the rapid development of new energy vehicles and the diversity of automobile products, the product structure of new energy vehicles is becoming more and more complex, and the processing precision requirements are high. New energy motor housing is an important part of new energy vehicles.

[0003] like Figure 1 As shown, the new energy motor housing 1 has a motor hole 2 for mounting the motor. The motor hole 2 consists of three levels: a first-level motor hole, a second-level motor hole, and a third-level motor hole, coaxially arranged from bottom to top along the depth direction of the motor hole 2. For example, in one new energy motor housing 1, the diameter requirements are φ226mm, φ230mm, and φ231mm, respectively, and the total depth of the motor hole 2 is 221±0.05mm (where the effective depths of the first-level motor hole, second-level motor hole, and third-level motor hole are 30mm, 158mm, and 33mm, respectively). Furthermore, the motor hole in the new energy motor housing has a diameter tolerance of H7 (-0.17 / -0.216)mm, a coaxiality requirement of 0.05mm, and a cylindricity requirement of 0.02mm. Therefore, the motor holes in new energy motor housings have large diameters, deep machining depths, and strict form and position tolerances, as well as high precision requirements for coaxiality and cylindricity. This places extremely high demands on equipment and tooling.

[0004] In the existing technology, horizontal machining equipment with an HSK-A100 spindle is used to process the motor hole, and the tool adopts a single-edge fine-tuning tool holder and a blade for processing. The tool is heavy, the processing efficiency is low, and the cylindricity, coaxiality, position and other requirements of the motor hole cannot be guaranteed. Summary of the Invention

[0005] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a processing technology for the motor hole of a new energy motor housing, which can ensure the precision requirements such as cylindricity, coaxiality, and position of the motor hole, and can improve the processing efficiency while improving the processing quality.

[0006] To achieve the above-mentioned object, the present invention provides a process for machining a motor hole in a new energy motor housing, comprising the following steps:

[0007] (1) Clamp the motor housing on the hydraulic fixture and install the rough machining tool on the spindle of the dual-spindle horizontal five-axis machining center;

[0008] (2) Rough machining the motor hole with a rough machining tool. The single-side allowance of the motor hole diameter is 0.15 mm ± 0.05, and the bottom allowance is 0.2 mm ± 0.05;

[0009] (3) Install the tool for machining the undercut groove on the spindle of the dual-spindle horizontal five-axis machining center, and finish the undercut groove plane at the bottom of the motor hole;

[0010] (4) Install a finishing tool on the spindle of a dual-spindle horizontal five-axis machining center and finish-machine the motor hole using the finishing tool;

[0011] The motor hole of the motor housing includes a first-stage motor hole, a second-stage motor hole and a third-stage motor hole coaxially arranged in sequence from bottom to top along the depth direction thereof, and the diameters of the first-stage motor hole, the second-stage motor hole and the third-stage motor hole increase in sequence;

[0012] (41) Move the first finishing tool to the initial position above the third-level motor hole at the motor hole opening, maintaining a safety height of at least 3mm; at a speed of 1500±250r / min and a feed of 400±50mm / min, move the first finishing tool down along the negative direction of the Z axis to a depth of 15±0.025mm below the first-level motor hole; then move the first finishing tool upward along the positive direction of the Z axis at a feed speed of 400±50mm / min to the initial position above the third-level motor hole; the finishing of the first-level motor hole and the second-level motor hole is completed;

[0013] (42) Move the second finishing tool to the initial position above the motor hole, maintaining a safety height of at least 3mm; at a speed of 1500±250r / min and a feed rate of 400±50mm / min, move the second finishing tool down along the negative direction of the Z axis to the junction of the second motor hole and the third-level motor hole; then move the second finishing tool upward along the positive direction of the Z axis at a feed rate of 400±50mm / min to the initial position above the third-level motor hole, and the finishing of the third-level motor hole is completed.

[0014] As a further improvement of the present invention, in step (2), the process of rough machining the motor hole includes:

[0015] (21) Move the first rough machining tool to the initial position above the third-level motor hole at the motor hole opening, maintaining a safety height of at least 3 mm; at a speed of 2500±250 r / min and a feed of 600±50 mm / min, move the first rough machining tool down along the negative direction of the Z axis to a depth of 15±0.025 mm below the first-level motor hole; then move the first rough machining tool upward along the positive direction of the Z axis at a feed speed of 600±50 mm / min to the initial position above the third-level motor hole; the rough machining of the first-level motor hole and the second-level motor hole is completed;

[0016] (22) Move the second rough machining tool to the initial position above the motor hole, maintaining a safety height of at least 3mm; at a speed of 2500±250r / min and a feed rate of 600±50mm / min, move the second rough machining tool down along the negative direction of the Z axis to the junction of the second motor hole and the third-level motor hole; then move the second rough machining tool upward along the positive direction of the Z axis at a feed rate of 600±50mm / min to the initial position above the third-level motor hole, and the rough machining of the third-level motor hole is completed.

[0017] As a further improvement of the present invention, the maximum outer diameter of the spindle housing of the dual-spindle horizontal five-axis machining center is smaller than the diameter of the motor hole; the lengths of the roughing tool and the finishing tool are smaller than the depth of the motor hole.

[0018] As a further improvement of the present invention, before finishing in step (3), the motor housing needs to be left to stand to release internal stress.

[0019] As a further improvement of the present invention, the first finishing tool is provided with a first finishing blade and a second finishing blade, which are respectively used to process the first-level motor hole and the second-level motor hole; the second finishing tool is provided with a third finishing blade, which is used to process the third-level motor hole; and guide strips are respectively provided corresponding to the first finishing blade, the second finishing blade, and the third finishing blade;

[0020] The guide bar of the finishing tool is 0.003mm lower than the corresponding boring edge of the finishing blade; the cutting edges of the first finishing blade, the second finishing blade and the third finishing blade are 0.015mm higher than the tail of the blade.

[0021] As a further improvement of the present invention, the first roughing tool is provided with a first roughing blade and a second roughing blade for machining the first-stage motor hole and the second-stage motor hole, respectively;

[0022] The second rough machining tool is provided with a third roughing blade and a fourth roughing blade. The third roughing blade is used for machining the hole wall of the third-level motor hole, and the fourth roughing blade is used for machining the chamfer of the third-level motor hole.

[0023] As a further improvement of the present invention, the rough machining tool includes a tool body and a tool handle, wherein the tool handle is used to be connected to the spindle of a dual-spindle horizontal five-axis machining center, and the tool body and the tool handle are connected through a flange.

[0024] As a further improvement of the present invention, the finishing tool includes a tool body and a tool handle, wherein the tool handle is used to be connected to the spindle of a dual-spindle horizontal five-axis machining center, and the tool body and the tool handle are connected via a flange.

[0025] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0026] (1) The processing technology of the motor hole of the new energy motor housing of the present invention is to first roughen the hole, then process the plane of the tool groove at the bottom of the motor hole, and finally finish the motor hole. The maximum outer diameter of the spindle housing of the dual-spindle horizontal five-axis machining center is smaller than the diameter of the motor hole, which can effectively shorten the effective length of the roughing and finishing tools, making it have the advantages of small size and light weight, and can avoid the problems of heavy self-weight, large tool length jump, insufficient spindle torque / tension, etc. of the existing roughing and finishing tools. On this basis, the three-level motor hole can be processed by different tool combinations, which can avoid the problem of excessive tool length when the same tool is used for the three-level motor hole. At the same time, using the same tool to process the two-level motor holes at the same time can maximize the processing efficiency and ensure the coaxiality requirements of the multi-level motor holes.

[0027] (2) The processing technology of the motor hole of the new energy motor housing of the present invention adopts a dual-spindle horizontal five-axis machining center and a hydraulic clamp to clamp the workpiece. It can process holes and surfaces of multiple angles in sequence and effectively ensure the dimensional accuracy requirements such as cylindricity, position, and coaxiality of the coaxially arranged multi-stage motor holes.

[0028] (3) In the present invention, the finishing tool for the motor hole of the new energy motor housing adopts a PCD guide bar boring tool, which can be equipped with multiple blades and has high processing efficiency. Moreover, by fine-tuning the flanges of the tool body and the tool holder, the tool runout can be reduced to ≤0.003mm, and the tool itself has low runout. At the same time, the guide bar is lower than the boring blade of the finishing tool, and the hole wall is supported by the guide bar. Through the above design, the PCD guide bar boring tool of the embodiment of the present invention can effectively meet the precision requirements such as cylindricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the three-in-one motor housing structure according to an embodiment of the present invention;

[0030] Figure 2 This is a structural schematic diagram of a three-in-one motor housing clamped on a hydraulic fixture according to an embodiment of the present invention;

[0031] Figure 3 A cross-sectional view of a motor hole of a three-in-one motor housing according to an embodiment of the present invention;

[0032] Figure 4 This is a schematic structural diagram of the HSK-A63 slim spindle housing according to an embodiment of the present invention;

[0033] Figure 5 This is a schematic diagram of the first roughing knife structure according to an embodiment of the present invention;

[0034] Figure 6 This is a schematic diagram of the second roughing knife structure according to an embodiment of the present invention;

[0035] Figure 7A schematic structural diagram of a tool for machining an undercut according to an embodiment of the present invention;

[0036] Figure 8 Schematic diagram of the structure of a first finishing tool according to an embodiment of the present invention;

[0037] Figure 9 Schematic diagram of the structure of a second finishing tool according to an embodiment of the present invention;

[0038] Figure 10 Schematic diagram of the first rough machining in the machining process of an embodiment of the present invention;

[0039] Figure 11 Schematic diagram of the second rough machining in the machining process of an embodiment of the present invention;

[0040] Figure 12 Schematic diagram of milling bottom surface undercut in the machining process of an embodiment of the present invention;

[0041] Figure 13 Schematic diagram of the first finishing process in the processing technology of the embodiment of the present invention;

[0042] Figure 14 Schematic diagram of the second finishing process in the processing technology of an embodiment of the present invention.

[0043] In all the drawings, the same figure marks represent the same technical features, specifically: 1. motor housing; 2. motor hole; 3. hydraulic clamp; 4. spindle housing; 5. first roughing blade; 6. second roughing blade; 7. third roughing blade; 8. fourth roughing blade; 9. tool for processing the undercut; 10. first fine blade; 11. second fine blade; 12. first guide bar; 13. second guide bar; 14. third fine blade; 15. third guide bar. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0045] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0047] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0048] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0049] As a preferred embodiment of the present invention, the processing technology of the motor hole of the new energy motor housing of the embodiment of the present invention includes the following steps:

[0050] (1) Clamp the motor housing on the hydraulic fixture and install the rough machining tool on the spindle of the dual-spindle horizontal five-axis machining center;

[0051] like Figure 1As shown, a workpiece, a three-in-one motor housing, is clamped on a hydraulic fixture 3, secured by a hydraulic cylinder. The motor housing 1 is mounted on the hydraulic fixture 3, which is a five-axis fixture capable of movement along the X, Y, and Z axes, as well as rotation along the X and Y axes. The hydraulic fixture features detection for proper clamping, hydraulic tightening, and hydraulic release, effectively preventing errors caused by improper clamping, tightening, or loosening.

[0052] like Figure 4 As shown, the spindle housing 4 of a dual-spindle horizontal five-axis machining center has a slim profile, and the preferred spindle model is HSK-A63. The maximum outer diameter of the spindle housing is smaller than the diameter of the motor hole; the lengths of the roughing and finishing tools are smaller than the depth of the motor hole, and more preferably, the lengths of the roughing and finishing tools are less than half the depth of the motor hole.

[0053] (2) Rough machining the motor hole with a rough machining tool. The single-side allowance of the motor hole diameter is 0.15 mm ± 0.05, and the bottom allowance is 0.2 mm ± 0.05. The single-side allowance of the hole diameter is used for fine machining, and the bottom allowance is used to machine the bottom groove plane of the hole.

[0054] After the motor housing 1 is clamped on the hydraulic fixture 3 and all error-proofing checks of the hydraulic fixture 3 are passed, the motor hole is rough-machined first.

[0055] The motor hole is divided into three levels, including a first-level motor hole, a second-level motor hole and a third-level motor hole coaxially arranged from bottom to top along the depth direction of the motor hole, and the diameters of the first-level motor hole, the second-level motor hole and the third-level motor hole increase in sequence.

[0056] (21) Move the first rough machining tool quickly to the initial position above the third-level motor hole at the motor hole opening, maintaining a safety height of at least 3 mm; at a speed of 2500±250 r / min and a feed of 600±50 mm / min, move the first rough machining tool down along the negative direction of the Z axis to a depth of 15±0.025 mm below the first-level motor hole; the first rough machining tool then moves upward along the positive direction of the Z axis at a feed speed of 600±50 mm / min to the initial position above the third-level motor hole; the rough machining of the first-level motor hole and the second-level motor hole is completed;

[0057] (22) Move the second rough machining tool quickly to the initial position above the motor hole, maintaining a safety height of at least 3mm; at a speed of 2500±250r / min and a feed rate of 600±50mm / min, move the second rough machining tool down along the negative direction of the Z axis to the junction of the second motor hole and the third-level motor hole; then move the second rough machining tool upward along the positive direction of the Z axis at a feed rate of 600±50mm / min to the initial position above the third-level motor hole; the rough machining of the third-level motor hole is completed.

[0058] In a specific embodiment, the total depth of the motor hole is 221±0.05mm, the diameters of the first-stage motor hole, the second-stage motor hole, and the third-stage motor hole are D226, D230, and D231, respectively, and the effective depths are 30mm, 158mm, and 33mm, respectively. The top of the third-stage motor hole is a distance (at least 18mm) from the motor hole opening, and the bottom of the first motor hole is a distance (at least 15mm) from the bottom of the motor hole. The above steps are specifically as follows:

[0059] The first roughing tool moves rapidly to -15mm in the negative direction of the Z axis at the motor hole opening, maintaining a safety height of 3mm. At a speed of 2500±250r / min and a feed rate of 600±50mm / min, the first roughing tool moves down to -236 in the negative direction of the Z axis. The first roughing tool then moves upward in the positive direction of the Z axis to -15mm in the negative direction of the Z axis at a feed rate of 600±50mm / min. Roughing of the first-level motor hole and the second-level motor hole (motor holes D226 and D230) is completed.

[0060] Move the second roughing tool quickly to -15mm in the negative direction of the Z axis at the opening of the motor hole; maintain a safety height of 3mm, with a rotation speed of 2500±250r / min and a feed speed of 600±50mm / min, and move the second roughing tool down to -48mm in the negative direction of the Z axis; then move the second roughing tool upward along the positive direction of the Z axis to -15mm in the negative direction of the Z axis at a feed speed of 600±50mm / min, and the roughing of the third-level motor hole (motor hole D231) is completed.

[0061] In this embodiment of the present invention, the roughing tools used (including the first and second roughing tools) are split components, each consisting of a tool body and a tool holder. The tool holder is used to connect to the spindle of a dual-spindle horizontal five-axis machining center. The tool body and tool holder are connected by a flange to facilitate adjustment of tool runout. The tool holder is made of SK material for rigidity, while the tool body is constructed of aluminum alloy for lightweight, resulting in a total weight of approximately 4 kg.

[0062] like Figure 5 and Figure 6 As shown, the first roughing tool is provided with a first roughing blade 5 and a second roughing blade 6, which are respectively used to process the first-level motor hole and the second-level motor hole (such as holes D226 and D230); the second roughing tool is used to process the third-level motor hole (such as motor hole D231), and the second roughing tool is provided with a third roughing blade 7 and a fourth roughing blade 8, wherein the third roughing blade 7 is used to process the hole wall of the third-level motor hole, and the fourth roughing blade 8 is used to process the chamfer of the third-level motor hole.

[0063] Since the diameter of the second-stage motor hole is larger than that of the first-stage motor hole, and the diameter of the third-stage motor hole is larger than that of the second-stage motor hole, the positions of the first to fourth roughing blades and the distances from the center axis of the roughing tool need to match the corresponding motor holes.

[0064] It should be noted that after rough machining the motor hole, the rest of the motor housing is typically machined first, followed by finish machining of the motor hole. Machining other parts of the motor housing can generate stress, which can cause deformation of the motor hole. Therefore, the motor housing needs to be left alone after rough machining and before finish machining to release internal stress. This prevents inconsistent machining allowances due to motor hole deformation and ensures precision finish machining.

[0065] (3) Install the tool for machining the undercut groove on the spindle of the dual-spindle horizontal five-axis machining center, and finish the undercut groove plane at the bottom of the motor hole;

[0066] The machining process of the motor hole bottom undercut plane by the undercut machining tool can be done by using the existing technology. Figure 7 As shown, the tool for processing the tool recess is not provided with an axial tool recess, and only the radial tool recess is processed by the slot milling cutter; the finishing tool is subjected to large force when processing the axial tool recess, and the separate radial tool recess is processed separately, which can effectively ensure the shape and position tolerance requirements of the hole wall processed by the finishing motor hole.

[0067] (4) Install a finishing tool on the spindle of a dual-spindle horizontal five-axis machining center and finish-machine the motor hole using the finishing tool;

[0068] (41) Move the first finishing tool quickly to the initial position above the third-level motor hole at the motor hole opening, maintaining a safety height of at least 3 mm; at a speed of 1500±250 r / min and a feed of 400±50 mm / min, move the first finishing tool down along the negative direction of the Z axis to a depth of 15±0.025 mm below the first-level motor hole; the first finishing tool then moves upward along the positive direction of the Z axis at a feed speed of 400±50 mm / min to the initial position above the third-level motor hole; the finishing of the first-level motor hole and the second-level motor hole is completed;

[0069] (42) Move the second finishing tool quickly to the initial position above the motor hole, maintaining a safety height of at least 3mm; at a speed of 1500±250r / min and a feed rate of 400±50mm / min, move the second finishing tool down along the negative direction of the Z axis to the junction of the second motor hole and the third-level motor hole; then move the second finishing tool upward along the positive direction of the Z axis at a feed rate of 400±50mm / min to the initial position above the third-level motor hole; the finishing of the third-level motor hole is completed.

[0070] In this embodiment, the following steps are specifically included:

[0071] The first finishing tool is rapidly moved to -15mm in the negative direction of the Z axis at the motor hole opening, maintaining a safety height of 3mm; at a speed of 1500±250r / min and a feed rate of 400±50mm / min, the first finishing tool is lowered to a depth of -236mm in the negative direction of the Z axis; the first finishing tool is then moved upward in the positive direction of the Z axis at a feed rate of 400±50mm / min to a position of -15mm in the negative direction of the Z axis at the motor hole opening, completing the finishing of the first-level motor hole and the second-level motor hole (motor holes D226 and D230);

[0072] Move the second finishing tool quickly to -15mm in the negative direction of the Z axis at the opening of the motor hole; maintain a safety height of 3mm, rotate at 1500±250r / min, feed at 400±50mm / min, and move the finishing tool down to -48mm in the negative direction of the Z axis; then move the second finishing tool upward along the positive direction of the Z axis to -15mm in the negative direction of the Z axis at a feed speed of 400±50mm / min, and the finishing of the third-level motor hole (motor hole D231) is completed.

[0073] In this embodiment, the finishing tool used is a PCD guide boring tool. The finishing tools (including the first and second finishing tools) are split, consisting of a tool body and a tool holder. The tool holder is connected to the spindle of a dual-spindle horizontal five-axis machining center. The tool body and tool holder are connected via a flange to facilitate tool runout adjustment. The total weight of the finishing tool is approximately 5.5 kg.

[0074] like Figure 8 and 9 As shown, the first finishing tool includes a first finishing blade 10, a second finishing blade 11, a first guide bar 12, and a second guide bar 13. The first finishing blade 10 and the second finishing blade 11 are used to machine the first-stage motor holes and the second-stage motor holes (e.g., holes D226 and D230), respectively. The first guide bar 12 and the second guide bar 13 are used to guide the first finishing tool during feeding. The second finishing tool includes a third finishing blade 14 and a third guide bar 15. The third finishing blade 14 is used to machine the third-stage motor holes (e.g., motor hole D231), and the third guide bar 15 is used to guide the second finishing tool during feeding.

[0075] Since the maximum outer diameter of the spindle of the dual-spindle horizontal five-axis machining center in this embodiment is smaller than the diameter of the motor hole, the length of the roughing tool and the finishing tool can be smaller than the depth of the motor hole. Therefore, the roughing tool or finishing tool for machining the first-level motor hole and the second-level motor hole uses the same tool (the length is smaller than the depth of the motor hole), and the third-level motor hole is machined with another roughing tool or finishing tool (the length is smaller than the depth of the motor hole). This can avoid the problem of the tool being too long when the same tool is used for the three-level motor holes. At the same time, using the same tool to machine the two-level motor holes at the same time can maximize the machining efficiency and ensure the coaxiality requirements of the multi-level motor holes.

[0076] It is understood that, because the diameter of the first-stage motor hole is smaller than the diameter of the second-stage motor hole, the vertical distance between the first finishing blade 10 and the center axis of the first finishing tool is smaller than the vertical distance between the second finishing blade 11 and the center axis of the first finishing tool. Similarly, the vertical distance between the third finishing blade 14 and the center axis of the second finishing tool is greater than the vertical distance between the second finishing blade 11 and the center axis of the first finishing tool.

[0077] Further preferably, the guide bars of the finishing tool are 0.003mm lower than the corresponding boring edges of the finishing blades. That is, the vertical distance between the first guide bar 12 and the center axis of the first finishing tool is 0.003mm less than the distance between the boring edge of the first finishing blade 10 and the axis of the motor hole. The vertical distance between the second guide bar 13 and the center axis of the first finishing tool is 0.003mm less than the distance between the boring edge of the second finishing blade 11 and the axis of the motor hole. The vertical distance between the third guide bar 15 and the center axis of the second finishing tool is 0.003mm less than the vertical distance between the boring edge of the third finishing blade 14 and the center axis of the second finishing tool. In addition, the edge and the tail of the first, second, and third finishing blades are required to be 0.015mm higher than the tail.

[0078] Therefore, in step (4), before finishing the motor hole, the guide bar of the finishing tool needs to be adjusted to be 0.003mm lower than the boring edge of the finishing blade, and the blade and the tail of the finishing blade need to be 0.015mm higher than the tail. After adjustment, when the spindle is stationary, the internal cooling of the finishing tool needs to be turned on, and the internal cooling pressure must be ≥4MPa.

[0079] The finishing tool in this embodiment of the present invention utilizes a PCD guide bar boring tool. Compared to the existing single-edge boring tool structure of a fine-tuning toolholder and insert, this PCD guide bar boring tool can accommodate multiple inserts, resulting in higher processing efficiency. Furthermore, fine-tuning of the flanges between the tool body and the tool holder can reduce tool runout to ≤0.003mm, minimizing tool runout. Furthermore, the guide bar is positioned below the boring edge of the finishing tool, providing support for the hole wall. This design effectively ensures that the PCD guide bar boring tool in this embodiment of the present invention can meet precision requirements such as cylindricity.

[0080] The maximum outer diameter of the spindle housing contour of the dual-spindle horizontal five-axis machining center in an embodiment of the present invention is smaller than the diameter of the motor hole. Therefore, when machining the motor hole, the spindle housing can enter the inside of the motor hole, and the rough machining and finishing tools for machining the motor hole can be as short as possible (the tool length can be less than 1 / 2 of the motor hole depth), which can avoid the problems of heavy weight of existing rough machining and finishing tools, large tool length runout, insufficient spindle torque / tension, etc.

[0081] Therefore, the roughing and finishing tools of the present invention are small in size and light in weight, and have the following advantages: a. Reduced energy consumption: The tool weighs little, and the power required when the processing equipment drives it to move is relatively small, thereby reducing energy consumption; b. Improved processing accuracy: The tool with a small weight has small inertia, and is easier to control during high-speed processing or complex trajectory processing. It can move more accurately along the predetermined trajectory, which helps to improve processing accuracy; c. Reduced equipment wear: Since the tool weighs little, the load on the processing equipment is small, which can reduce the force on the relevant parts of the equipment during movement, thereby reducing equipment wear and extending the service life of the equipment; d. Facilitated and quick tool change: Lighter tools are more convenient to operate when the tool changing device is in operation, which is conducive to increasing the tool changing speed and thus improving processing efficiency.

[0082] The present invention utilizes a dual-spindle horizontal five-axis machining center and a hydraulic clamp for workpiece clamping. This allows for simultaneous machining of holes and surfaces at multiple angles, effectively ensuring the dimensional accuracy requirements of coaxially arranged multi-stage motor holes. For example, in the present invention, roughing and finishing are performed simultaneously, with the same hydraulic clamping mechanism. This reduces positioning errors associated with multiple clampings, ensuring better machining accuracy. Furthermore, during simultaneous finishing, uniform machining allowances are achieved, resulting in a well-balanced tool cutting motion, further ensuring product accuracy.

[0083] In the machining process described herein, the motor hole is first rough-machined, followed by the finish machining of the undercut surface at the bottom of the hole, and finally the motor hole. The finishing tool utilizes a guide bar tool with flange adjustment and an internal cooling mechanism. After machining is complete, the finishing tool is retracted at the same speed as the machining speed. Once the tool is completely removed from the product, the spindle stops, and machining is complete. The motor hole finishing tool only cuts the sidewalls, not the bottom surface or the undercut. Force applied to the tool is consistent and minimal, and stress is released before finishing, reducing errors caused by post-machining deformation.

[0084] Therefore, the present invention ensures the coaxiality, position, cylindricity and other precision requirements of the motor hole by reasonably designing the processing tool, designing a reasonable process route and coordinating high-precision equipment.

[0085] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A processing technology for the motor hole of a new energy motor housing, characterized in that: The steps are as follows: (1) Clamp the motor housing on the hydraulic fixture and install the rough machining tool on the spindle of the dual-spindle horizontal five-axis machining center; (2) Rough machining the motor hole with a rough machining tool. The single-side allowance of the motor hole diameter is 0.15 mm ± 0.05, and the bottom allowance is 0.2 mm ± 0.05; (3) Install the tool for machining the undercut groove on the spindle of the dual-spindle horizontal five-axis machining center, and finish the undercut groove plane at the bottom of the motor hole; (4) Install a finishing tool on the spindle of a dual-spindle horizontal five-axis machining center and finish-machine the motor hole using the finishing tool; The motor hole of the motor housing includes a first-stage motor hole, a second-stage motor hole and a third-stage motor hole coaxially arranged in sequence from bottom to top along the depth direction thereof, and the diameters of the first-stage motor hole, the second-stage motor hole and the third-stage motor hole increase in sequence; (41) Move the first finishing tool to the initial position above the third-level motor hole at the motor hole opening, maintaining a safety height of at least 3mm; at a speed of 1500±250r / min and a feed of 400±50mm / min, move the first finishing tool down along the negative direction of the Z axis to a depth of 15±0.025mm below the first-level motor hole; then move the first finishing tool upward along the positive direction of the Z axis at a feed speed of 400±50mm / min to the initial position above the third-level motor hole; the finishing of the first-level motor hole and the second-level motor hole is completed; (42) Move the second finishing tool to the initial position above the motor hole, maintaining a safety height of at least 3 mm; at a speed of 1500 ± 250 r / min and a feed of 400 ± 50 mm / min, move the second finishing tool down along the negative direction of the Z axis to the junction of the second motor hole and the third motor hole; The second finishing tool then moves upward along the positive direction of the Z axis at a feed rate of 400±50mm / min to the initial position above the third-level motor hole, and the finishing of the third-level motor hole is completed.

2. The processing technology of the motor hole of the new energy motor housing according to claim 1 is characterized in that: In step (2), the process of rough machining the motor hole includes: (21) Move the first rough machining tool to the initial position above the third-level motor hole at the motor hole opening, maintaining a safety height of at least 3 mm; at a speed of 2500±250 r / min and a feed of 600±50 mm / min, move the first rough machining tool down along the negative direction of the Z axis to a depth of 15±0.025 mm below the first-level motor hole; then move the first rough machining tool upward along the positive direction of the Z axis at a feed speed of 600±50 mm / min to the initial position above the third-level motor hole; the rough machining of the first-level motor hole and the second-level motor hole is completed; (22) Move the second rough machining tool to the initial position above the motor hole, maintaining a safety height of at least 3mm; at a speed of 2500±250r / min and a feed rate of 600±50mm / min, move the second rough machining tool down along the negative direction of the Z axis to the junction of the second motor hole and the third-level motor hole; then move the second rough machining tool upward along the positive direction of the Z axis at a feed rate of 600±50mm / min to the initial position above the third-level motor hole, and the rough machining of the third-level motor hole is completed.

3. The processing technology of the motor hole of the new energy motor housing according to claim 1 is characterized in that: The maximum outer diameter of the spindle housing of the dual-spindle horizontal five-axis machining center is smaller than the diameter of the motor hole; the lengths of the roughing tool and the finishing tool are smaller than the depth of the motor hole.

4. The processing technology of the motor hole of the new energy motor housing according to claim 1 is characterized in that: Before finishing in step (3), the motor housing needs to be left to stand to release internal stress.

5. The processing technology for the motor hole of the new energy motor housing according to any one of claims 1 to 4, characterized in that: The first finishing tool is provided with a first finishing blade and a second finishing blade, which are used to process the first-level motor hole and the second-level motor hole respectively; the second finishing tool is provided with a third finishing blade, which is used to process the third-level motor hole; and guide strips are provided corresponding to the first finishing blade, the second finishing blade, and the third finishing blade respectively; The guide bar of the finishing tool is 0.003mm lower than the corresponding boring edge of the finishing blade; the cutting edges of the first finishing blade, the second finishing blade and the third finishing blade are 0.015mm higher than the tail of the blade.

6. The processing technology for the motor hole of the new energy motor housing according to claim 2 is characterized in that: The first roughing tool is provided with a first roughing blade and a second roughing blade for machining the first-stage motor hole and the second-stage motor hole respectively; The second rough machining tool is provided with a third roughing blade and a fourth roughing blade. The third roughing blade is used for machining the hole wall of the third-level motor hole, and the fourth roughing blade is used for machining the chamfer of the third-level motor hole.

7. The processing technology for the motor hole of the new energy motor housing according to any one of claims 1 to 4, characterized in that: The rough machining tool includes a tool body and a tool holder, wherein the tool holder is used to connect with the spindle of a dual-spindle horizontal five-axis machining center, and the tool body and the tool holder are connected through a flange.

8. The processing technology for the motor hole of the new energy motor housing according to any one of claims 1 to 4, characterized in that: The finishing tool includes a tool body and a tool holder, wherein the tool holder is used to connect with the spindle of a dual-spindle horizontal five-axis machining center, and the tool body and the tool holder are connected through a flange.

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