High-precision hole machining device and method for output shaft

Abstract

The invention relates to the technical field of machining, and discloses an output shaft high-precision hole machining device and method.The device comprises a lower three-jaw chuck, a fixing tool assembly is fixed to the lower three-jaw chuck, and an upper three-jaw chuck is fixed to the end of the fixing tool assembly; a plurality of supporting columns with the same length are arranged in the middle of the fixing tool assembly, and circumferential welding marks are arranged on the edges of the top ends of the supporting columns and used for recognizing and positioning. On the basis of the overall design of double-chuck clamping and a tool rigid frame, high-precision hole machining can be finally achieved on a common lathe through cooperation with circumferential welding mark auxiliary horizontal calibration, the high cost of purchasing a five-axis machine tool is avoided, and therefore the output shaft hole machining precision, efficiency and stability are remarkably improved; and meanwhile, dependence on high-end equipment is reduced, and the method is suitable for small and medium batch precision part machining scenes.

Description

Technical Field

[0001] This invention relates to the field of machining technology, and particularly to the field of high-precision hole machining tooling technology. Background Technology

[0002] Currently, the machining of high-precision holes in output shafts is generally carried out using horizontal lathes, which has drawbacks such as poor operability, low operating efficiency, and low machining accuracy. The main drawbacks are: First, poor positioning accuracy: When machining the output shaft on a horizontal lathe, the standard chuck has defects when directly clamping it. (1) The chuck clamping accuracy is poor and the clamping error is large; (2) When the output shaft is clamped horizontally, its center of gravity is far away from the clamping position, which will cause the shaft center line to be out of axis from the machine tool rotation center; (3) The chuck jaws are difficult to bore, and the boring error will be introduced into the machining error of the workpiece; (4) During machining, the workpiece speed is high, which will further increase the error.

[0003] Second, the operation is difficult and inefficient: the accuracy of the clamping datum and the design datum is insufficient, making it difficult to guarantee the machining requirements. It is necessary to increase manual calibration and adjustment of the design datum to meet the design requirements.

[0004] Third, insufficient cutting stability: This machining method is a high-speed cutting machining with a long arm and suspended shaft, that is, the ratio of the length of the shaft overhang to the length of the clamping distance is greater than 10. During cutting, it will cause workpiece vibration, which will make the machining quality (such as excessive roughness) fail to meet the requirements, and may also damage the tool, increase production costs and equipment maintenance frequency. Summary of the Invention

[0005] The purpose of this invention is to provide a high-precision hole processing device for output shafts, so as to solve many defects of the original processing method and achieve advantages such as increased positioning accuracy, convenient operation, good stability, improved product quality, and increased processing efficiency.

[0006] To solve the above-mentioned technical problems, the present invention provides a high-precision hole machining device for output shafts, including a lower three-jaw chuck, on which a fixed tooling assembly is fixed, and an upper three-jaw chuck is fixed at the end of the fixed tooling assembly; the middle part of the fixed tooling assembly consists of multiple support columns of the same length, and the top edge of the support columns has a circumferential weld mark, which is used for identification and positioning.

[0007] The number of support columns is four, distributed at the four corners of a rectangle.

[0008] The top of the support column is inserted and fixed with an upper fixing plate. The upper fixing plate has a top fixing through hole for connecting and fixing the upper three-jaw chuck. The circumferential welding mark is located at the junction of the support column and the upper fixing plate.

[0009] The bottom edge of the support column has a circumferential weld mark for identification and positioning.

[0010] The bottom end of the support column is inserted and fixed with a tooling base. The tooling base has a bottom fixing through hole for connecting and fixing the lower three-jaw chuck. The circumferential welding mark is located at the junction of the support column and the tooling base.

[0011] The upper fixing plate is fixed to the upper three-jaw chuck by a second fixing bolt that is inserted upwards into the upper fixing plate and the upper three-jaw chuck, and a second spring washer is fitted on the second fixing bolt.

[0012] The tooling base is fixed to the lower three-jaw chuck by inserting the bottom fixing through hole downwards and the first fixing bolt of the lower three-jaw chuck, and the first fixing bolt is fitted with a first spring washer.

[0013] The top surface of the upper fixing plate has a disc-shaped or annular boss, and the bottom of the upper three-jaw chuck has a groove that matches the boss; the center of the end of the support column has a boss structure for positioning and insertion.

[0014] Both the lower three-jaw chuck and the upper three-jaw chuck are short, round, standard three-jaw chucks.

[0015] The present invention also provides a method for machining high-precision holes in an output shaft, using the high-precision hole machining apparatus for an output shaft as described above, comprising the following steps: S1. Assembly: Assemble and fix the lower three-jaw chuck, the fixed tooling assembly, and the upper three-jaw chuck; S2. Centering: The workpiece to be processed is vertically loaded into the lower three-jaw chuck, the fixed tooling assembly, and the upper three-jaw chuck. The lower three-jaw chuck and the upper three-jaw chuck clamp the workpiece. During clamping, the workpiece is adjusted by the gap between the support columns. S3. Horizontal positioning: By identifying the position of the circumferential welding mark, the overall level of the lower three-jaw chuck, the fixed tooling assembly, and the upper three-jaw chuck is determined, and the level is adjusted to make the workpiece vertical. S4. Vertical boring: Boring the workpiece vertically from top to bottom.

[0016] Compared to existing technologies, this invention uses a lower three-jaw chuck and an upper three-jaw chuck to clamp the workpiece together, forming a bidirectional fixed support. This solves the problem of easy skewing when a single chuck clamps slender shaft-like workpieces, ensuring the workpiece's perpendicularity. The workpiece position can be adjusted through the gap between the support columns, avoiding the tedious manual alignment required by traditional four-jaw chucks. Based on circumferential welding marks, the tooling level can be quickly identified, replacing traditional leveling instruments and significantly reducing auxiliary time. The upper fixed plate and upper chuck are engaged by a boss, and the boss insertion design at the end of the support columns ensures assembly coaxiality. The vertical top-down boring feed method effectively avoids tool deflection caused by gravity in horizontal machining, improving the hole's positional accuracy. At the same time, combined with the rigid support of the double chucks, it can effectively suppress cutting vibration.

[0017] Furthermore, based on the overall design of dual chuck clamping and rigid tooling frame, combined with circumferential welding marks to assist in horizontal calibration, the rectangular distribution structure of the support columns not only disperses cutting forces and reduces chatter, meeting the requirements of high-precision hole machining, but also achieves compatibility with workpieces of different diameters by replacing the support columns or fixing plates. Moreover, it ultimately enables high-precision hole machining on ordinary lathes, avoiding the high cost of purchasing five-axis machine tools. This significantly improves the accuracy, efficiency, and stability of output shaft hole machining, while reducing dependence on high-end equipment, making it suitable for small to medium batch precision parts machining scenarios.

[0018] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0019] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0020] Figure 1 This is a schematic diagram of the structure of at least one embodiment of the present invention; Figure 2 yes Figure 1 Schematic diagram of the upper and middle three-jaw chuck; Figure 3 yes Figure 1 Schematic diagram of the fixed tooling assembly.

[0021] In the diagram: 1-Lower three-jaw chuck, 2-First fixing bolt, 3-First spring washer, 4-Fixed tooling assembly, 5-Second fixing bolt, 6-Second spring washer, 7-Upper three-jaw chuck, 41-Tooling base, 42-Support column, 43-Upper fixing plate, 44-Top fixing through hole, 45-Bottom fixing through hole, 46-Circumferential welding mark. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the embodiments of this invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details are presented in the embodiments of this invention to facilitate a better understanding of this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments. The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of this invention. The embodiments can be combined with and referenced by each other without contradiction.

[0023] Example 1 like Figures 1 to 3 The high-precision hole machining device for output shaft shown includes a lower three-jaw chuck 1, on which a fixed tooling assembly 4 is fixed, and an upper three-jaw chuck 7 is fixed at the end of the fixed tooling assembly 4; the middle part of the fixed tooling assembly 4 has multiple support columns 42 of the same length, and the top edge of the support columns 42 has a circumferential weld mark 46, which is used for identification and positioning.

[0024] Example 2 Based on Example 1, there are four support columns 42, which are distributed at the four corners of a rectangle.

[0025] Furthermore, an upper fixing plate 43 is inserted and fixed at the top of the support column 42. The upper fixing plate 43 has a top fixing through hole 44 for connecting and fixing the upper three-jaw chuck 7. The circumferential welding mark 46 is located at the junction of the support column 42 and the upper fixing plate 43.

[0026] Furthermore, the upper fixing plate 43 is fixed to the upper three-jaw chuck 7 by a second fixing bolt 5 inserted upwards into the upper fixing plate 43 and the upper three-jaw chuck 7, and a second spring washer 6 is fitted on the second fixing bolt 5.

[0027] Furthermore, both the lower three-jaw chuck 1 and the upper three-jaw chuck 7 are short, round, standard three-jaw chucks.

[0028] It is not difficult to see that this embodiment corresponds to Embodiment 1, and this embodiment can be implemented in conjunction with Embodiment 1. The relevant technical details mentioned in Embodiment 1 are still valid in this embodiment, and will not be repeated here to reduce repetition. Accordingly, the relevant technical details mentioned in this embodiment can also be applied in Embodiment 1.

[0029] Example 3 Based on Embodiment 1, the bottom edge of the support column 42 has a circumferential weld mark 46 for identification and positioning.

[0030] Furthermore, a tooling base 41 is inserted and fixed at the bottom end of the support column 42. The tooling base 41 has a bottom fixing through hole 45 for connecting and fixing the lower three-jaw chuck 1. The circumferential welding mark 46 is located at the junction of the support column 42 and the tooling base 41.

[0031] Furthermore, the tooling base 41 is fixed to the lower three-jaw chuck 1 by inserting downward into the bottom fixing through hole 45 and the first fixing bolt 2 of the lower three-jaw chuck 1, and the first fixing bolt 2 is fitted with a first spring washer 3.

[0032] Furthermore, the top surface of the upper fixing plate 43 has a disc-shaped or annular boss, and the bottom of the upper three-jaw chuck 7 has a groove that matches the boss; the center of the end of the support column 42 has a boss structure for positioning and insertion.

[0033] Since Embodiment 2 corresponds to this embodiment, this embodiment can be implemented in conjunction with Embodiment 2. The relevant technical details mentioned in Embodiment 2 remain valid in this embodiment, and the technical effects achievable in Embodiment 2 can also be realized in this embodiment. To reduce repetition, they will not be repeated here. Correspondingly, the relevant technical details mentioned in this embodiment can also be applied to Embodiment 2.

[0034] Example 4 A method for machining high-precision holes in an output shaft, using embodiments 1 to 3 as described above, includes the following steps: S1. Assembly: Assemble and fix the lower three-jaw chuck 1, the fixed tooling assembly 4, and the upper three-jaw chuck 7. S2, Centering: The workpiece to be processed is vertically loaded into the lower three-jaw chuck 1, the fixed tooling assembly 4, and the upper three-jaw chuck 7. The lower three-jaw chuck 1 and the upper three-jaw chuck 7 clamp the workpiece. During clamping, the workpiece is adjusted through the gap between the support columns 42. S3. Horizontal positioning: By identifying the position of the circumferential welding mark 46, the overall level of the lower three-jaw chuck 1, the fixed tooling assembly 4, and the upper three-jaw chuck 7 is determined, and the level is adjusted to make the workpiece vertical. S4. Vertical boring: Boring the workpiece vertically from top to bottom.

[0035] The steps of the various methods described above are only for clarity. In practice, they can be combined into one step or some steps can be split into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent. Adding insignificant modifications or introducing insignificant designs to the algorithm or process, but without changing the core design of the algorithm and process, are also within the scope of protection of this patent.

[0036] Example 5 Based on the above embodiments, the base is designed as a square structure with 4 countersunk holes and 6 through holes. The 4 countersunk holes of the base are connected to the 4 support columns and are tightly welded by circumferential welding. Bolts are used to fix the operating table through the 6 through holes to achieve the functions of fixing and precise positioning.

[0037] The upper fixing plate adopts a circular structure with 4 countersunk holes and 6 through holes. The upper fixing plate is connected to 4 support columns through the 4 countersunk holes and is tightly welded by circumferential welding. The bolts are used to fix a standard three-jaw chuck through the 6 through holes to achieve the functions of fixing and precise positioning.

[0038] Boring the inner surface of a standard three-jaw chuck to ensure its coaxiality meets requirements; then installing the output shaft into the standard three-jaw chuck. The upper end of the high-precision rigid fixed tooling assembly is mounted in a standard three-jaw chuck and connected by fixing bolt 2. The lower high-precision rigid fixed tooling assembly is then fixed to the operating table of the horizontal lathe and connected by fixing bolt 1. Tighten the bolts to the standard torque according to the thread size. Use grease to attach 8 cylindrical pins of the same length as the spline inside the spline. Align the outer diameter of the upper end of the 8 cylindrical pins, ensuring that the runout is no more than 0.01 mm. Select a suitable high-precision cutting tool, control the cutting parameters, and follow... Figure 1 The inner diameter of the copper bushing of the output shaft is machined to the value φA.

[0039] In use, the output shaft is placed in a standard three-jaw chuck for machining, as shown in Figure 8. After machining, the bolts are removed. Once the tool is clamped, machining can be completed in one go, improving machining efficiency and providing versatility.

[0040] The base, upper fixing plate, fixing bolts, and support columns are made of steel plates.

[0041] The welding method selected is circumferential welding, which can be used at extremely low temperatures (-45℃).

[0042] The coaxiality of the processed output shaft is 0.005mm-0.015mm.

[0043] The vertical machining center uses the technical solution of this embodiment to clamp the vertically placed workpiece. A precision dial indicator is then used to calibrate the generatrices at the four phase lines of datum A, with the runout requirement not exceeding 0.003. The circular datum A is then calibrated, with the runout requirement not exceeding 0.005. Rough boring, semi-finish boring, and finish boring are performed to the required specifications. Before each step, the internal cuttings in the hole must be completely removed. This achieves high-precision, highly stable clamping, shortens clamping time, improves machining efficiency, and is convenient to operate and maintain.

[0044] Therefore, by utilizing the self-centering clamping function of the three-jaw chuck and the positioning clamping function of the tooling, and in conjunction with the positioning reference, the shaft parts can be quickly centered and reliably clamped, ensuring coaxiality and dimensional accuracy during machining.

[0045] Those skilled in the art will understand that the above embodiments can be modified in form and detail in practical applications without departing from the spirit and scope of the invention.

[0046] Generally, the core components of the tooling include a precise positioning structure (high-precision rigid fixed tooling assembly structure), a standard three-jaw chuck, and workpieces (such as output shafts). The high-precision rigid fixed tooling assembly structure is formed by circumferential welding of parts such as the base, support column, and upper fixing plate to fix the standard three-jaw chuck and the vertical machining center worktable. The standard three-jaw chuck is driven by bevel gears to make the three chucks move radially synchronously, realizing the self-centering clamping of the workpiece and ensuring that the workpiece axis is aligned with the spindle axis.

[0047] The fixed fixture assembly, consisting of a base and upper fixing plate, is welded together in a tight circular weld to form a rigid frame. This frame securely connects the standard three-jaw chuck to the lathe operating table. During assembly, the frame's high-strength structural characteristics provide a stable support reference for the chuck, offsetting the impact of cutting forces. During chuck operation, the fixture structure, through rigid constraints, suppresses vibration and displacement of the chuck and workpiece. Combined with the chuck's self-centering function, it ensures that workpieces such as the output shaft use the machined outer diameter as a centering reference, achieving high-precision clamping and machining. During operation, the output shaft can be periodically inspected, cleaned, and rotated without disassembly, ensuring convenient and quick operation, easy maintenance, and low cost.

Claims

1. A high-precision hole machining device for output shafts, characterized in that: It includes a lower three-jaw chuck (1), on which a fixed tooling assembly (4) is fixed, and an upper three-jaw chuck (7) is fixed at the end of the fixed tooling assembly (4); the middle part of the fixed tooling assembly (4) consists of multiple support columns (42) of the same length, and there is a circumferential weld mark (46) at the top edge of the support column (42), which is used for identification and positioning.

2. The high-precision hole machining device for output shaft as described in claim 1, characterized in that: The number of the support columns (42) is four, which are distributed at the four corners of a rectangle.

3. The high-precision hole machining device for output shaft as described in claim 1, characterized in that: The top of the support column (42) is inserted and fixed with an upper fixing plate (43). The upper fixing plate (43) has a top fixing through hole (44) for connecting and fixing the upper three-jaw chuck (7). The circumferential welding mark (46) is located at the junction of the support column (42) and the upper fixing plate (43).

4. The high-precision hole machining device for output shaft as described in claim 1, characterized in that: The support column (42) has a circumferential weld mark (46) at the bottom edge for identification and positioning.

5. The high-precision hole machining device for output shaft as described in claim 4, characterized in that: The bottom end of the support column (42) is inserted and fixed with a tooling base (41). The tooling base (41) has a bottom fixing through hole (45) for connecting and fixing the lower three-jaw chuck (1). The circumferential welding mark (46) is located at the junction of the support column (42) and the tooling base (41).

6. The high-precision hole machining device for output shaft as described in claim 3, characterized in that: The upper fixing plate (43) is fixed to the upper three-jaw chuck (7) by a second fixing bolt (5) inserted upward into the upper fixing plate (43) and the upper three-jaw chuck (7), and a second spring washer (6) is fitted on the second fixing bolt (5).

7. The high-precision hole machining device for output shaft as described in claim 5, characterized in that: The tooling base (41) is fixed to the lower three-jaw chuck (1) by the first fixing bolt (2) inserted downward into the bottom fixing through hole (45) and the lower three-jaw chuck (1). The first fixing bolt (2) is fitted with a first spring washer (3).

8. The high-precision hole machining device for output shaft as described in claim 3, characterized in that: The upper fixing plate (43) has a disc-shaped or ring-shaped boss on its top surface, and the bottom of the upper three-jaw chuck (7) has a groove matching the boss; the support column (42) has a boss structure at the center of its end for positioning and insertion.

9. The high-precision hole machining device for output shaft as described in claim 1, characterized in that: Both the lower three-jaw chuck (1) and the upper three-jaw chuck (7) are short, round, standard three-jaw chucks.

10. The high-precision hole machining method for the output shaft as described in claim 1, characterized in that: The high-precision hole machining apparatus for output shafts as described in any one of claims 1 to 9 includes the following steps: S1. Assembly: Assemble and fix the lower three-jaw chuck (1), the fixed tooling assembly (4), and the upper three-jaw chuck (7); S2, Centering: The workpiece to be processed is vertically loaded into the lower three-jaw chuck (1), the fixed tooling assembly (4), and the upper three-jaw chuck (7). The lower three-jaw chuck (1) and the upper three-jaw chuck (7) clamp the workpiece. When clamping, the workpiece is adjusted by the gap between the support columns (42). S3, Horizontal positioning: By identifying the position of the circumferential welding mark (46), the overall level of the lower three-jaw chuck (1), the fixed tooling assembly (4), and the upper three-jaw chuck (7) is determined, and the level is adjusted to make the workpiece vertical; S4. Vertical boring: Boring the workpiece vertically from top to bottom.

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