Machining device and machining method for high-precision stepped holes in two ends

Abstract

The invention discloses a machining device and method for high-precision stepped holes in the two ends. The machining precision and machining efficiency of products can be effectively improved. A first boring rod seat and a second boring rod seat are arranged on a base, a to-be-machined area is arranged between the first boring rod seat and the second boring rod seat, the to-be-machined area is used for placing a to-be-machined workpiece, bushings are arranged on supporting holes of the first boring rod seat and the second boring rod seat, boring bushings are arranged in the bushings, and the first boring rod seat and the second boring rod seat are arranged on the first boring rod seat and the second boring rod seat. The positioning block is arranged outside the boring sleeve and used for fixing the boring sleeve in the lining, the two ends of the boring rod are arranged in the boring sleeve, the middle of the boring rod penetrates through a workpiece to be machined, and a boring cutter is detachably installed on the boring rod. When the stepped holes in the two ends of the to-be-machined workpiece are machined, the boring rod is driven by the machine tool spindle to rotate and matched with the boring cutter to sequentially machine the stepped holes in the two ends of the to-be-machined workpiece, and the stepped holes in the two ends of the to-be-machined workpiece are ground and polished through the grinding device after machining.

Description

Technical Field

[0001] The present application relates to the field of equipment manufacturing technology, and in particular to a processing device and method for high-precision stepped holes at both ends. Background Art

[0002] In the field of mechanical manufacturing, many parts need to be processed with high-precision stepped hole structures at both ends. High-precision stepped holes at both ends are often used in various mechanical components with strict requirements on fitting accuracy, sealing and strength, such as some high-end hydraulic valve bodies, precision transmission sleeves, high-stability grinding heads, etc. The processing quality directly affects the performance, stability and service life of the entire mechanical system.

[0003] Currently, the traditional method for machining stepped holes at both ends involves multiple clampings and separate machining of the two holes. This method has many significant drawbacks. Multiple clampings can lead to inconsistent positioning datums, and the position and posture of the workpiece may vary slightly with each clamping, making it difficult to effectively guarantee geometric accuracy, such as coaxiality and perpendicularity, of the two end holes. Machining accuracy is low, and because both ends need to be machined separately, each end face undergoes a series of operations, including clamping, positioning, machining, and disassembly. The entire machining process is cumbersome and time-consuming, especially in mass production. This inefficient machining method can seriously impact production schedules and reduce production efficiency. Summary of the Invention

[0004] In order to solve the above technical problems, the present application provides a processing device and a processing method for high-precision stepped holes at both ends.

[0005] The technical solution provided in this application is described below: A first aspect of the present application provides a device for machining high-precision stepped holes at both ends, the device comprising: a base, a first boring bar seat, a second boring bar seat, a boring bar, a boring sleeve, a bushing, and a positioning block; The first boring bar seat and the second boring bar seat are provided on the base, and a to-be-processed area is provided between the first boring bar seat and the second boring bar seat, and the to-be-processed area is used to place the workpiece to be processed. The support holes of the first boring bar seat and the second boring bar seat are both provided with the bushings, and the boring sleeve is arranged in the bushing, and the positioning block is arranged outside the boring sleeve for fixing the boring sleeve in the bushing. Both ends of the boring bar are arranged in the boring sleeve, and the middle part of the boring bar passes through the workpiece to be processed. A boring tool is detachably mounted on the boring bar; when the step holes at both ends of the workpiece to be processed are processed, the boring bar is driven to rotate by the machine tool spindle, and the step holes at both ends of the workpiece to be processed are processed in turn by the boring tool, and after processing, the step holes at both ends of the workpiece to be processed are ground and polished by a grinding device.

[0006] Optionally, the center heights of the support holes of the first boring bar seat and the second boring bar seat, and the center heights of the stepped holes at both ends of the workpiece to be machined are located on the same straight line.

[0007] Optionally, a first active area is provided between the first boring bar seat and the workpiece to be machined, and a second active area is provided between the second boring bar seat and the workpiece to be machined.

[0008] Optionally, a first mounting position and a second mounting position are provided on the boring bar, and the boring tool can be detachably mounted on both the first mounting position and the second mounting position.

[0009] Optionally, the boring bar and the boring sleeve are connected in a clearance fit manner.

[0010] Optionally, the boring sleeve and the bushing are connected by interference fit.

[0011] Optionally, the first boring bar seat and the second boring bar seat are both mounted on the base via bolts.

[0012] Optionally, the grinding device includes a positioning spindle, a positioning sleeve and a grinding sleeve, the positioning sleeve and the grinding sleeve are respectively arranged in the step holes at both ends of the workpiece to be processed, the positioning spindle passes through the positioning sleeve, the grinding sleeve and the step holes at both ends of the workpiece to be processed, and the positioning spindle cooperates with the positioning sleeve and the grinding sleeve to grind and polish the step holes at both ends of the workpiece to be processed.

[0013] Optionally, the processing device further includes an end face grinding disc, which is detachably mounted on the positioning spindle and is arranged on both end faces of the workpiece to be processed for grinding and polishing the both end faces of the workpiece to be processed.

[0014] A second aspect of the present application provides a method for machining a high-precision stepped hole at both ends, the method comprising: Fix the base on the machine table to ensure that the base is level and stable; The first boring bar seat and the second boring bar seat are mounted on the base by bolts, and the distance between the two is adjusted so that the center heights of the support holes of the two and the center heights of the stepped holes at both ends of the workpiece to be machined are on the same straight line; Installing bushings on the supporting holes of the first boring bar seat and the second boring bar seat, pressing the boring sleeves into the bushings through interference fit, and fixing the boring sleeves with positioning blocks; Place the workpiece to be processed in the processing area, ensuring that there is space between the two end faces of the workpiece and the first boring bar seat and the second boring bar seat; Adjusting the position of the workpiece to be machined so that the center line of the workpiece is aligned with the center line of the boring bar; Pass both ends of the boring bar through the boring sleeve and the middle part through the workpiece to be machined; Installing boring cutters on the first and second mounting positions of the boring bar respectively, and adjusting the radial positions of the boring cutters to match the designed dimensions of the stepped hole; Start the machine tool, the machine tool spindle rotates and drives the boring bar to rotate, after cutting one end of the workpiece, and then cut the other end of the workpiece to form the finishing of the step hole; Install the positioning sleeve and the grinding sleeve into the stepped holes at both ends of the machined workpiece respectively; Install the positioning spindle and pass it through the positioning sleeve, grinding sleeve and the stepped holes at both ends of the workpiece; After the grinding sleeve is positioned by the positioning mandrel, the grinding paste is applied to the grinding sleeve, and the inner wall of the step hole is ground and polished respectively under the action of the grinding paste by rotating the grinding sleeve. The positioning sleeve is fixed to remove processing marks and burrs, and improve the surface roughness, roundness and cylindricity of the inner hole of the workpiece; Check the dimensional accuracy and surface roughness of the step hole to ensure that the step hole meets high precision requirements.

[0015] It can be seen from the above technical solutions that this application has the following beneficial effects: 1. By using a boring bar, a boring sleeve and a bushing structure, the present application enables the device to ensure the stability and positioning accuracy of the boring bar during the processing, thereby achieving high-precision processing of the stepped holes at both ends of the workpiece, helping to reduce processing errors and improve the overall quality and performance of the product.

[0016] 2. This device allows the machining of stepped holes at both ends of the workpiece to be completed in one clamping, avoiding errors caused by multiple clamping and positioning, improving machining consistency, and at the same time reducing machining procedures and auxiliary time, thereby improving work efficiency.

[0017] 3. The boring sleeve is fixed in the bushing by the positioning block, and both ends of the boring bar are set in the boring sleeve, which effectively ensures the stability and rigidity of the boring bar during the processing, reduces vibration and deviation, and thus improves the processing accuracy and surface quality.

[0018] 4. After processing, the step hole is ground and polished by a grinding device, which further improves the surface quality and precision of the step hole, meets the requirements of high-precision processing, helps to eliminate burrs and unevenness generated during the processing, and makes the step hole smoother and more wear-resistant. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in this application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 This is a three-dimensional schematic diagram of the overall structure of the processing device for high-precision stepped holes at both ends of this application; Figure 2 This is a front view of the overall structure of the processing device for high-precision stepped holes at both ends of this application; Figure 3 This is a front cross-sectional view of the overall structure of the processing device for high-precision stepped holes at both ends of this application; Figure 4 This is a side view of the overall structure of the processing device for high-precision stepped holes at both ends of this application; Figure 5 for Figure 2 Structural cross-sectional view of AA in the middle; Figure 6 This is a schematic diagram of the structure of the grinding device in the processing device for high-precision stepped holes at both ends of this application; Figure 7 This is a schematic cross-sectional view of the grinding device structure in the processing device for high-precision stepped holes at both ends of this application; Figure 8 This is a schematic cross-sectional view of the structure of the grinding device in the processing device for high-precision stepped holes at both ends of this application, in which an end surface grinding disc is added to the grinding device.

[0021] Figure 9 It is a flow chart of the method for processing high-precision stepped holes at both ends of the present application. DETAILED DESCRIPTION

[0022] In this application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only used to illustrate the relative position relationship between the various components or components, and do not particularly limit the specific installation orientation of the various components or components.

[0023] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to express a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0024] Furthermore, the terms "installed," "disposed," "provided with," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections, indirect connections through an intermediary, or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0025] In addition, the structures, proportions, sizes, etc. drawn in the drawings in this application are only used to match the contents disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the efficacy and purpose that can be achieved by this application.

[0026] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in this application. Obviously, the embodiments described are only some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] Traditional methods for machining stepped holes at both ends often involve multiple clamping operations, each involving separate machining of the two holes. This method has numerous significant drawbacks. Multiple clamping operations can lead to inconsistent positioning datums, and slight variations in the workpiece position and orientation can occur with each clamping. This makes it difficult to effectively guarantee geometric accuracy, such as coaxiality and perpendicularity, of the two holes. Machining accuracy is low, and because both ends must be machined separately, each end face undergoes a series of operations, including clamping, positioning, machining, and disassembly. The entire process is cumbersome and time-consuming, especially in mass production. This inefficient method can severely impact production schedules and lead to low production efficiency.

[0028] Based on this, the present application provides a processing device and method for high-precision stepped holes at both ends. Compared with traditional adjustment methods, it can achieve high-precision processing of stepped holes at both ends of the workpiece, which helps to reduce processing errors and improve the overall quality and performance of the product. It also allows the stepped holes at both ends of the workpiece to be processed in one clamping, avoiding the errors caused by multiple clamping and positioning, improving processing consistency, and at the same time reducing processing steps and auxiliary time, thereby improving work efficiency.

[0029] See also Figures 1 to 8In a first aspect, the present application provides a device for machining high-precision stepped holes at both ends, the device comprising: a base 6, a first boring bar seat 2, a second boring bar seat 10, a boring bar 1, a boring sleeve 3, a bushing 4 and a positioning block 5; The first boring bar seat 2 and the second boring bar seat 10 are provided on the base 6, and a to-be-processed area is provided between the first boring bar seat 2 and the second boring bar seat 10, and the to-be-processed area is used to place the workpiece 8 to be processed. The support holes of the first boring bar seat 2 and the second boring bar seat 10 are both provided with the bushing 4, the boring sleeve 3 is arranged in the bushing 4, and the positioning block 5 is arranged outside the boring sleeve 3 for fixing the boring sleeve 3 in the bushing 4. Both ends of the boring bar 1 are arranged in the boring sleeve 3, and the middle part of the boring bar 1 passes through the workpiece 8 to be processed. A boring tool is detachably mounted on the boring bar 1; when the step holes at both ends of the workpiece 8 to be processed are processed, the boring bar 1 is driven to rotate by the machine tool spindle, and the step holes at both ends of the workpiece to be processed are processed in turn with the boring tool, and after processing, the step holes of the workpiece 8 to be processed are ground and polished by a grinding device.

[0030] First, the functions and effects of each component in this application are explained: Base 6: Base 6 is the foundation of the entire processing device. Base 6 is used to support and fix other components. The first boring bar seat 2 and the second boring bar seat 10 are both fixed on the base 6, providing a stable platform for the entire processing process.

[0031] The first boring bar seat 2 and the second boring bar seat 10: The first boring bar seat 2 and the second boring bar seat 10 are both mounted on the base 6 by bolts. The two boring bar seats have the same structure and are symmetrically arranged on the base 6. There are support holes on the first boring bar seat 2 and the second boring bar seat 10, and bushings 4 are installed on the support holes; the first boring bar seat 2 and the second boring bar seat 10 are used to support both ends of the boring bar 1 to ensure the stability and positioning accuracy of the boring bar 1 during the machining process. They also serve as a reference surface during the machining process to provide the correct relative position for the boring bar 1 and the workpiece 8 to be machined.

[0032] Boring bar 1: A long metal rod, its ends inserted into a boring sleeve 3 and its center section extending through the workpiece 8. It features mounting points for removably attaching a boring cutter. Boring bar 1 is a crucial component in the machining process, driven by the machine tool to rotate and coordinate with the boring cutter to create a stepped hole in the workpiece 8.

[0033] Boring sleeve 3 and bushing 4: Both the boring sleeve 3 and the bushing 4 are annular components. The bushing 4 is installed on the supporting holes of the first boring bar seat 2 and the second boring bar seat 10, and the boring sleeve 3 is arranged in the bushing 4. The bushing 4 is used to protect the supporting holes of the first boring bar seat 2 and the second boring bar seat 10, reduce wear and extend service life. The boring sleeve 3 is used to support and guide the boring bar 1 to ensure the stability and positioning accuracy of the boring bar 1 during the machining process. At the same time, the cooperation of the boring sleeve 3 and the bushing 4 also helps to reduce vibration and offset and improve machining accuracy.

[0034] Positioning block 5: The positioning block 5 is used to fix the boring sleeve 3 in the bushing 4 to prevent the boring sleeve 3 from moving or deflecting during the processing. The fixing effect of the positioning block 5 can ensure the stability and positioning accuracy of the boring bar 1 during the processing.

[0035] Workpiece 8 to be machined: The workpiece 8 to be machined is placed in the area to be machined between the first boring bar seat 2 and the second boring bar seat 10, and the step hole is machined by the cooperation of the boring bar 1 and the boring cutter.

[0036] Grinding device: After the processing is completed, the step holes at both ends of the workpiece 8 are ground and polished by the grinding device, which can further improve the surface quality and accuracy of the step holes and meet the requirements of high-precision processing.

[0037] The processing device for high-precision step holes at both ends realizes high-precision processing and grinding and polishing of the step holes at both ends of the workpiece through the close cooperation and coordinated work of various components. It has the advantages of simple operation and high processing accuracy, and is suitable for various high-precision step hole processing occasions.

[0038] Optionally, the center heights of the support holes of the first boring bar seat 2 and the second boring bar seat 10, and the center heights of the stepped holes at both ends of the workpiece 8 to be machined are located on the same straight line.

[0039] In the embodiment of the present application, the first boring bar seat 2 and the second boring bar seat 10 are components that support the boring bar 1. The center height of the support holes of the first boring bar seat 2 and the second boring bar seat 10 refers to the geometric center point of the hole axis. These two center points serve as reference points for the installation and rotation of the boring bar 1, and determine the position and direction of the boring bar 1 during the processing. The coaxiality of the first boring bar seat 2 and the second boring bar seat 10 ensures the stability and balance of the boring bar 1 during the rotation process, reduces vibration and deviation, and thus improves the processing accuracy.

[0040] Among them, the center height of the stepped holes at both ends of the workpiece 8 to be processed refers to the geometric center point of the axis of the stepped holes required to be processed at both ends of the workpiece 8 to be processed. These two center points are coaxial with the center height of the support hole of the boring bar seat, ensuring that the boring bar 1 can accurately penetrate the workpiece and perform precise stepped hole processing on both ends of the workpiece, thereby ensuring that the relative position between the workpiece and the boring bar 1 during the processing is accurate, thereby improving the processing quality and efficiency.

[0041] By ensuring that the first boring bar seat 2, the second boring bar seat 10 and the center points of the holes at both ends of the workpiece to be processed 8 are located on the same straight line, the errors and deviations in the processing process can be minimized, thereby significantly improving the processing accuracy of the stepped hole. The coaxial design enables the boring bar 1 to maintain a stable trajectory during rotation, ensuring that the boring tool can accurately cut according to the preset path, thereby obtaining a high-quality stepped hole.

[0042] Optionally, a first active area is provided between the first boring bar seat 2 and the workpiece 8 to be machined, and a second active area is provided between the second boring bar seat 10 and the workpiece 8 to be machined.

[0043] In the embodiment of the present application, the first active area is located between the first boring bar seat 2 and the workpiece 8 to be machined. It is the space through which the boring bar 1 passes when extending from the first boring bar seat 2 to the workpiece 8 to be machined. There is no direct rigid structure connecting the first boring bar seat 2 and the workpiece to be machined in the first active area, but rather a certain spatial gap is maintained. Correspondingly, the second active area is located between the second boring bar seat 10 and the workpiece to be machined, and is arranged symmetrically with the first active area. It is the space through which the boring bar 1 passes when extending from the workpiece 8 to the second boring bar seat 10 to be machined. The second active area also maintains a certain spatial gap, and there is no direct rigid structure connecting the second boring bar seat 10 and the workpiece 8 to be machined.

[0044] The existence of the first active area and the second active area can ensure that the boring bar 1 can accurately penetrate the workpiece 8 to be machined and machine the stepped hole.

[0045] During the workpiece installation process, the active area provides necessary space for the workpiece. At the same time, during the processing process, if the workpiece 8 to be processed needs to be fine-tuned or repositioned, the active area also provides sufficient operating space.

[0046] Optionally, a first mounting position 7 and a second mounting position 9 are provided on the boring bar 1 , and the boring tool can be detachably mounted on both the first mounting position 7 and the second mounting position 9 .

[0047] In the embodiment of the present application, both the first mounting position 7 and the second mounting position 9 are provided on the boring bar 1. The first mounting position 7 is used to mount a boring tool for machining a stepped hole at one end of a workpiece 8 to be machined, while the second mounting position 9 is used to mount a boring tool for machining a stepped hole at the other end of the workpiece. The provision of the first mounting position 7 and the second mounting position 9 facilitates quick installation and removal of the boring tool.

[0048] By installing the boring tool on the first mounting position 7 and the second mounting position 9 respectively, the processing device can perform step hole processing on both ends of the workpiece 8 to be processed in turn, which effectively improves the processing efficiency and can ensure the coaxiality and processing accuracy of the step holes at both ends of the workpiece 8 to be processed.

[0049] Optionally, the boring bar 1 and the boring sleeve 3 are connected in a clearance fit manner.

[0050] In the embodiment of the present application, the clearance fit refers to a fitting mode in which the diameter of the boring bar 1 is smaller than the inner diameter of the boring sleeve 3, and a certain radial clearance is formed after the two are assembled. The clearance fit allows the boring bar 1 to slide and rotate freely in the boring sleeve 3, so that when the boring bar 1 is driven to rotate by the machine tool, the boring bar 1 can rotate on the boring sleeve 3, and cooperate with the boring cutter on the boring bar 1 to process the two ends of the workpiece 8 to be processed in sequence.

[0051] Optionally, the boring sleeve 3 and the bushing 4 are connected by interference fit.

[0052] In the embodiment of the present application, an interference fit means that the outer diameter of the boring sleeve 3 is slightly larger than the inner diameter of the bushing 4. During assembly, pressure is applied to force the boring sleeve 3 into the bushing 4, achieving a tight connection. In this fit, there is no gap between the boring sleeve 3 and the bushing 4, ensuring stability and firmness after the connection between the two.

[0053] Specifically, when the boring sleeve 3 is pressed into the bushing 4, both the outer surface of the boring sleeve 3 and the inner surface of the bushing 4 undergo slight elastic deformation, generating contact pressure. This contact pressure creates strong friction between the boring sleeve 3 and the bushing 4, preventing relative movement or separation between the two during machining. Furthermore, the interference fit provides extremely high connection strength, capable of withstanding the various forces and vibrations generated during machining, ensuring that the connection between the boring sleeve 3 and the bushing 4 will not loosen or fail. This is crucial for high-precision step hole machining, as any slight loosening of the connection can lead to machining errors and affect machining quality.

[0054] And because the interference fit connection realizes a tight fit between the boring sleeve 3 and the bushing 4, it can ensure that the relative position between the two is accurate. This high positioning accuracy helps to improve the processing accuracy and reduce the processing deviation caused by connection errors.

[0055] Optionally, the grinding device includes a positioning spindle 11, a positioning sleeve 12 and a grinding sleeve 13, the positioning sleeve 12 and the grinding sleeve 13 are respectively arranged in the step holes at both ends of the workpiece 8 to be processed, the positioning spindle 11 passes through the positioning sleeve 12, the grinding sleeve 13 and the step holes at both ends of the workpiece 8 to be processed, and the positioning spindle 11 cooperates with the positioning sleeve 12 and the grinding sleeve 13 to grind and polish the step holes at both ends of the workpiece 8 to be processed.

[0056] In the embodiment of the present application, the positioning spindle 11 is a slender cylinder whose diameter is smaller than the minimum inner diameter of the step hole of the workpiece 8 to be processed so that it can smoothly pass through the step hole, but the length of the spindle must meet the requirements of being able to simultaneously pass through the step holes at both ends of the workpiece as well as the positioning sleeve 12 and the grinding sleeve 13.

[0057] Among them, the positioning sleeve 12 is a hollow cylinder, the inner diameter of which matches the outer diameter of the positioning spindle 11, and the outer diameter matches the inner diameter of the step hole at one end of the workpiece 8 to be processed, playing a positioning and supporting role. The positioning sleeve 12 is installed in the step hole at one end of the workpiece 8 to be processed. Through close cooperation with the positioning spindle 11, it ensures that the positioning spindle 11 remains coaxial with the step hole at this end during the penetration process, providing an accurate positioning reference for the grinding process.

[0058] Grinding sleeve 13 is also a hollow cylinder, with an inner diameter that matches the outer diameter of positioning spindle 11 and an outer diameter that is slightly larger than the inner diameter of the stepped hole at the other end of workpiece 8 to be machined. This allows grinding pressure to be applied to the inner wall of the stepped hole during the grinding process, and the outer surface of grinding sleeve 13 is capable of finely grinding the inner wall of the stepped hole. Grinding sleeve 13 is installed in the stepped hole at the other end of the workpiece and cooperates with positioning sleeve 12. Driven by positioning spindle 11, grinding and polishing the inner wall of the stepped hole is performed, removing burrs, tool marks, and other defects generated during the machining process, thereby improving the surface quality and dimensional accuracy of the stepped hole.

[0059] Specifically, in actual application, first install the positioning sleeve 12 into the stepped hole at one end of the workpiece 8 to be processed, ensuring that the positioning sleeve 12 fits tightly with the stepped hole and is accurately positioned. Then place the workpiece 8 to be processed in a suitable working position with the stepped hole at the other end facing upward to facilitate the installation of the grinding sleeve 13. Then install the grinding sleeve 13 into the stepped hole at the other end of the workpiece, also ensuring that it fits and is accurately positioned.

[0060] Then insert the positioning spindle 11 into the positioning sleeve 12 at one end of the workpiece, and pass through the positioning sleeve 12, the grinding sleeve 13 and the step holes at both ends of the workpiece in sequence until it extends out from the other end, ensuring that the spindle remains coaxial with the positioning sleeve 12, the grinding sleeve 13 and the step hole.

[0061] After the positioning mandrel 11 is installed in place, the positioning sleeve 12 is tightly fitted with the positioning mandrel 11, and the positioning sleeve 12 is fixed. Abrasive paste is applied to the grinding sleeve, and the grinding sleeve is rotated. Under the action of the grinding paste, the inner wall of the step hole is ground and polished respectively to remove processing marks and burrs, and improve the surface roughness, roundness and cylindricity of the inner hole of the workpiece. It should be noted that the step hole of the workpiece 8 to be processed is ground and polished by the grinding sleeve 13. After one hole is processed, the positioning mandrel 11 is taken out, and then the positioning sleeve 12 and the grinding sleeve 13 are swapped, and the other hole is ground.

[0062] During the rotation process, the outer surface of the grinding sleeve 13 rubs and cuts against the inner wall of the step hole, gradually removing burrs, knife marks and other defects on the inner wall of the step hole, making the inner wall smooth. At the same time, the positioning sleeve 12 ensures that the spindle always maintains coaxiality with the step hole during the rotation process, thereby ensuring the stability and uniformity of the grinding process.

[0063] Optionally, the processing device also includes an end face grinding disc 14, which is detachably mounted on the positioning spindle 11. The end face grinding disc 14 is arranged on both end faces of the workpiece to be processed and is used to grind and polish the both end faces of the workpiece 8 to be processed.

[0064] In the embodiment of the present application, the end surface grinding disc 14 is a circular disc-shaped structure. Its diameter is set according to the end surface size of the workpiece 8 to be processed, and is not specifically limited here. It ensures that the end surface grinding disc 14 can completely cover the end surface of the workpiece 8 to be processed, achieving comprehensive grinding. The end surface grinding disc 14 is detachably mounted on the positioning mandrel 11, allowing the end surface grinding disc 14 to be easily replaced to meet different processing requirements or when the grinding disc is worn.

[0065] In actual application, the end face grinding disc 14 is first securely installed on the positioning spindle 11. When grinding begins, the end face grinding disc 14 rotates. Under the joint action of contact pressure, the end face grinding disc 14 grinds and polishes the end face of the workpiece. During the grinding process, the end face of the workpiece is gradually flattened, and the surface roughness is continuously reduced until the predetermined processing accuracy and surface quality requirements are met.

[0066] See also Figure 9 The second aspect of the present application provides a method for machining high-precision stepped holes at both ends, the method comprising: 101. Fix the base on the machine tool table to ensure that the base is level and stable; 102. Install the first boring bar seat and the second boring bar seat on the base using bolts, and adjust the distance between the two so that the center heights of the support holes of the two are aligned with the center heights of the stepped holes at both ends of the workpiece to be machined; 103. Install bushings in the openings of the first boring bar seat and the second boring bar seat, press the boring sleeves into the bushings through interference fit, and secure the boring sleeves with positioning blocks; 104. Place the workpiece to be processed in the processing area, ensuring that there is space between the two end faces of the workpiece and the first boring bar seat and the second boring bar seat; 105. Adjust the position of the workpiece to be processed so that the center line of the workpiece is aligned with the center line of the boring bar; 106. Pass both ends of the boring bar through the boring sleeve and the middle part through the workpiece to be machined; 107. Install boring cutters on the first and second mounting positions of the boring bar, respectively, and adjust the radial positions of the boring cutters to match the designed dimensions of the stepped hole; 108. Start the machine tool, the machine tool spindle rotates and drives the boring bar to rotate, cutting one end of the workpiece and then cutting the other end of the workpiece to form the finished step hole; 109. Install the positioning sleeve and the grinding sleeve into the stepped holes at both ends of the machined workpiece respectively; 110. Install the positioning spindle and pass it through the positioning sleeve, grinding sleeve and the stepped holes at both ends of the workpiece; 111. After positioning the grinding sleeve by the positioning mandrel, apply grinding paste on the grinding sleeve, rotate the grinding sleeve, and grind and polish the inner wall of the step hole under the action of the grinding paste. The positioning sleeve is fixed to remove processing marks and burrs, and improve the surface roughness, roundness and cylindricity of the inner hole of the workpiece; 112. Check the dimensional accuracy and surface roughness of the step hole to ensure that the step hole meets high precision requirements.

[0067] It should be noted that the above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A processing device for high-precision stepped holes at both ends, characterized in that: The device comprises: a base, a first boring bar seat, a second boring bar seat, a boring bar, a boring sleeve, a bushing and a positioning block; The first boring bar seat and the second boring bar seat are provided on the base, and a to-be-processed area is provided between the first boring bar seat and the second boring bar seat, and the to-be-processed area is used to place the workpiece to be processed. The support holes of the first boring bar seat and the second boring bar seat are both provided with the bushings, and the boring sleeve is arranged in the bushing, and the positioning block is arranged outside the boring sleeve for fixing the boring sleeve in the bushing. Both ends of the boring bar are arranged in the boring sleeve, and the middle part of the boring bar passes through the workpiece to be processed. A boring tool is detachably mounted on the boring bar; when the step holes at both ends of the workpiece to be processed are processed, the boring bar is driven to rotate by the machine tool spindle, and the step holes at both ends of the workpiece to be processed are processed in turn by the boring tool, and after processing, the step holes at both ends of the workpiece to be processed are ground and polished by a grinding device.

2. The processing device for high-precision stepped holes at both ends according to claim 1, characterized in that: The center heights of the support holes of the first boring bar seat and the second boring bar seat, and the center heights of the stepped holes at both ends of the workpiece to be machined are located on the same straight line.

3. The processing device for high-precision stepped holes at both ends according to claim 1, characterized in that: A first active area is provided between the first boring bar seat and the workpiece to be machined, and a second active area is provided between the second boring bar seat and the workpiece to be machined.

4. The processing device for high-precision stepped holes at both ends according to claim 3, characterized in that: The boring bar is provided with a first mounting position and a second mounting position, and the boring tool can be detachably mounted on both the first mounting position and the second mounting position.

5. The processing device for high-precision stepped holes at both ends according to claim 1, characterized in that: The boring bar and the boring sleeve are connected in a clearance fit manner.

6. The processing device for high-precision stepped holes at both ends according to claim 1, characterized in that: The boring sleeve and the bushing are connected in an interference fit manner.

7. The processing device for high-precision stepped holes at both ends according to claim 1, characterized in that: The first boring bar seat and the second boring bar seat are both mounted on the base through bolts.

8. The processing device for high-precision stepped holes at both ends according to claim 1, characterized in that: The grinding device includes a positioning spindle, a positioning sleeve and a grinding sleeve. The positioning sleeve and the grinding sleeve are respectively arranged in the step holes at both ends of the workpiece to be processed. The positioning spindle passes through the positioning sleeve, the grinding sleeve and the step holes at both ends of the workpiece to be processed. The positioning spindle cooperates with the positioning sleeve and the grinding sleeve to grind and polish the step holes at both ends of the workpiece to be processed.

9. The processing device for high-precision stepped holes at both ends according to claim 8, characterized in that: The processing device also includes an end surface grinding disc, which is detachably mounted on the positioning spindle and is arranged on both end surfaces of the workpiece to be processed for grinding and polishing the end surfaces of the workpiece to be processed.

10. A method for machining high-precision stepped holes at both ends, characterized in that: The processing method comprises: Fix the base on the machine table to ensure that the base is level and stable; The first boring bar seat and the second boring bar seat are mounted on the base by bolts, and the distance between the two is adjusted so that the center heights of the support holes of the two and the center heights of the stepped holes at both ends of the workpiece to be machined are on the same straight line; Installing bushings on the supporting holes of the first boring bar seat and the second boring bar seat, pressing the boring sleeves into the bushings through interference fit, and fixing the boring sleeves with positioning blocks; Place the workpiece to be processed in the processing area, ensuring that there is space between the two end faces of the workpiece and the first boring bar seat and the second boring bar seat; Adjusting the position of the workpiece to be machined so that the center line of the workpiece is aligned with the center line of the boring bar; Pass both ends of the boring bar through the boring sleeve and the middle part through the workpiece to be machined; Installing boring cutters on the first and second mounting positions of the boring bar respectively, and adjusting the radial positions of the boring cutters to match the designed dimensions of the stepped hole; Start the machine tool, the machine tool spindle rotates and drives the boring bar to rotate, after cutting one end of the workpiece, and then cut the other end of the workpiece to form the finishing of the step hole; Install the positioning sleeve and the grinding sleeve into the stepped holes at both ends of the machined workpiece respectively; Install the positioning spindle and pass it through the positioning sleeve, grinding sleeve and the stepped holes at both ends of the workpiece; After the grinding sleeve is positioned by the positioning mandrel, the grinding paste is applied to the grinding sleeve, and the inner wall of the step hole is ground and polished respectively under the action of the grinding paste by rotating the grinding sleeve. The positioning sleeve is fixed to remove processing marks and burrs, and improve the surface roughness, roundness and cylindricity of the inner hole of the workpiece; Check the dimensional accuracy and surface roughness of the step hole to ensure that the step hole meets high precision requirements.

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